Predicted and experimental aerodynamic forces on the Darrieus rotor

NASA Astrophysics Data System (ADS)

Paraschivoiu, I.

1983-12-01

The present paper compares the aerodynamic loads predicted by a double-multiple-streamtube model with wind tunnel measurements for a straight-bladed Darrieus rotor. Thus the CARDAA computer code uses two constant-interference factors in the induced velocity for estimating the aerodynamic loads. This code has been improved by considering the variation in the upwind and downwind induced velocities as a function of the blade position, and, in this case, the CARDAAV code is used. The Boeing-Vertol dynamic-stall model is incorporated in both the CARDAA and CARDAAV codes, and a better approach is obtained. The transient normal- and tangential-force coefficients predicted with and without dynamic-stall effects are compared with wind tunnel data for one and two NACA 0018 straight-bladed rotors. The results are given for a rotor with a large solidity (chord-to-radius ratio of 0.20) at two tip-speed ratios (X = 1.5 and 3.0) and at a low Reynolds number of 3.8 x 10 to the 4th. The comparisons between experimental data and theoretical results show the CARDAAV predictions to be more accurate than those estimated by the CARDAA code.

Visualizing whole-brain DTI tractography with GPU-based Tuboids and LoD management.

PubMed

Petrovic, Vid; Fallon, James; Kuester, Falko

2007-01-01

Diffusion Tensor Imaging (DTI) of the human brain, coupled with tractography techniques, enable the extraction of large-collections of three-dimensional tract pathways per subject. These pathways and pathway bundles represent the connectivity between different brain regions and are critical for the understanding of brain related diseases. A flexible and efficient GPU-based rendering technique for DTI tractography data is presented that addresses common performance bottlenecks and image-quality issues, allowing interactive render rates to be achieved on commodity hardware. An occlusion query-based pathway LoD management system for streamlines/streamtubes/tuboids is introduced that optimizes input geometry, vertex processing, and fragment processing loads, and helps reduce overdraw. The tuboid, a fully-shaded streamtube impostor constructed entirely on the GPU from streamline vertices, is also introduced. Unlike full streamtubes and other impostor constructs, tuboids require little to no preprocessing or extra space over the original streamline data. The supported fragment processing levels of detail range from texture-based draft shading to full raycast normal computation, Phong shading, environment mapping, and curvature-correct text labeling. The presented text labeling technique for tuboids provides adaptive, aesthetically pleasing labels that appear attached to the surface of the tubes. Furthermore, an occlusion query aggregating and scheduling scheme for tuboids is described that reduces the query overhead. Results for a tractography dataset are presented, and demonstrate that LoD-managed tuboids offer benefits over traditional streamtubes both in performance and appearance.

A Free Wake Numerical Simulation for Darrieus Vertical Axis Wind Turbine Performance Prediction

NASA Astrophysics Data System (ADS)

Belu, Radian

2010-11-01

In the last four decades, several aerodynamic prediction models have been formulated for the Darrieus wind turbine performances and characteristics. We can identified two families: stream-tube and vortex. The paper presents a simplified numerical techniques for simulating vertical axis wind turbine flow, based on the lifting line theory and a free vortex wake model, including dynamic stall effects for predicting the performances of a 3-D vertical axis wind turbine. A vortex model is used in which the wake is composed of trailing stream-wise and shedding span-wise vortices, whose strengths are equal to the change in the bound vortex strength as required by the Helmholz and Kelvin theorems. Performance parameters are computed by application of the Biot-Savart law along with the Kutta-Jukowski theorem and a semi-empirical stall model. We tested the developed model with an adaptation of the earlier multiple stream-tube performance prediction model for the Darrieus turbines. Predictions by using our method are shown to compare favorably with existing experimental data and the outputs of other numerical models. The method can predict accurately the local and global performances of a vertical axis wind turbine, and can be used in the design and optimization of wind turbines for built environment applications.

Mixing-controlled reactive transport on travel times in heterogeneous media

NASA Astrophysics Data System (ADS)

Luo, J.; Cirpka, O.

2008-05-01

Modeling mixing-controlled reactive transport using traditional spatial discretization of the domain requires identifying the spatial distributions of hydraulic and reactive parameters including mixing-related quantities such as dispersivities and kinetic mass-transfer coefficients. In most applications, breakthrough curves of conservative and reactive compounds are measured at only a few locations and models are calibrated by matching these breakthrough curves, which is an ill posed inverse problem. By contrast, travel-time based transport models avoid costly aquifer characterization. By considering breakthrough curves measured on different scales, one can distinguish between mixing, which is a prerequisite for reactions, and spreading, which per se does not foster reactions. In the travel-time based framework, the breakthrough curve of a solute crossing an observation plane, or ending in a well, is interpreted as the weighted average of concentrations in an ensemble of non-interacting streamtubes, each of which is characterized by a distinct travel-time value. Mixing is described by longitudinal dispersion and/or kinetic mass transfer along individual streamtubes, whereas spreading is characterized by the distribution of travel times which also determines the weights associated to each stream tube. Key issues in using the travel-time based framework include the description of mixing mechanisms and the estimation of the travel-time distribution. In this work, we account for both apparent longitudinal dispersion and kinetic mass transfer as mixing mechanisms, thus generalizing the stochastic-convective model with or without inter-phase mass transfer and the advective-dispersive streamtube model. We present a nonparametric approach of determining the travel-time distribution, given a breakthrough curve integrated over an observation plane and estimated mixing parameters. The latter approach is superior to fitting parametric models in cases where the true travel-time distribution exhibits multiple peaks or long tails. It is demonstrated that there is freedom for the combinations of mixing parameters and travel-time distributions to fit conservative breakthrough curves and describe the tailing. Reactive transport cases with a bimolecular instantaneous irreversible reaction and a dual Michaelis-Menten problem demonstrate that the mixing introduced by local dispersion and mass transfer may be described by apparent mean mass transfer with coefficients evaluated by local breakthrough curves.

Prediction of Down-Gradient Impacts of DNAPL Source Depletion Using Tracer Techniques

NASA Astrophysics Data System (ADS)

Basu, N. B.; Fure, A. D.; Jawitz, J. W.

2006-12-01

Four simplified DNAPL source depletion models that have been discussed in the literature recently are evaluated for the prediction of long-term effects of source depletion under natural gradient flow. These models are simple in form (a power function equation is an example) but are shown here to serve as mathematical analogs to complex multiphase flow and transport simulators. One of the source depletion models, the equilibrium streamtube model, is shown to be relatively easily parameterized using non-reactive and reactive tracers. Non-reactive tracers are used to characterize the aquifer heterogeneity while reactive tracers are used to describe the mean DNAPL mass and its distribution. This information is then used in a Lagrangian framework to predict source remediation performance. In a Lagrangian approach the source zone is conceptualized as a collection of non-interacting streamtubes with hydrodynamic and DNAPL heterogeneity represented by the variation of the travel time and DNAPL saturation among the streamtubes. The travel time statistics are estimated from the non-reactive tracer data while the DNAPL distribution statistics are estimated from the reactive tracer data. The combined statistics are used to define an analytical solution for contaminant dissolution under natural gradient flow. The tracer prediction technique compared favorably with results from a multiphase flow and transport simulator UTCHEM in domains with different hydrodynamic heterogeneity (variance of the log conductivity field = 0.2, 1 and 3).

Simulation of a hydrocarbon fueled scramjet exhaust

NASA Technical Reports Server (NTRS)

Leng, J.

1982-01-01

Exhaust nozzle flow fields for a fully integrated, hydrocarbon burning scramjet were calculated for flight conditions of M (undisturbed free stream) = 4 at 6.1 km altitude and M (undisturbed free stream) = 6 at 30.5 km altitude. Equilibrium flow, frozen flow, and finite rate chemistry effects are considered. All flow fields were calculated by method of characteristics. Finite rate chemistry results were evaluated by a one dimensional code (Bittker) using streamtube area distributions extracted from the equilibrium flow field, and compared to very slow artificial rate cases for the same streamtube area distribution. Several candidate substitute gas mixtures, designed to simulate the gas dynamics of the real engine exhaust flow, were examined. Two mixtures are found to give excellent simulations of the specified exhaust flow fields when evaluated by the same method of characteristics computer code.

Users manual for Streamtube Curvature Analysis: Analytical method for predicting the pressure distribution about a nacelle at transonic speeds, volume 1

NASA Technical Reports Server (NTRS)

Keith, J. S.; Ferguson, D. R.; Heck, P. H.

1972-01-01

The computer program, Streamtube Curvature Analysis, is described for the engineering user and for the programmer. The user oriented documentation includes a description of the mathematical governing equations, their use in the solution, and the method of solution. The general logical flow of the program is outlined and detailed instructions for program usage and operation are explained. General procedures for program use and the program capabilities and limitations are described. From the standpoint of the grammar, the overlay structure of the program is described. The various storage tables are defined and their uses explained. The input and output are discussed in detail. The program listing includes numerous comments so that the logical flow within the program is easily followed. A test case showing input data and output format is included as well as an error printout description.

Optimal villi density for maximal oxygen uptake in the human placenta.

PubMed

Serov, A S; Salafia, C M; Brownbill, P; Grebenkov, D S; Filoche, M

2015-01-07

We present a stream-tube model of oxygen exchange inside a human placenta functional unit (a placentone). The effect of villi density on oxygen transfer efficiency is assessed by numerically solving the diffusion-convection equation in a 2D+1D geometry for a wide range of villi densities. For each set of physiological parameters, we observe the existence of an optimal villi density providing a maximal oxygen uptake as a trade-off between the incoming oxygen flow and the absorbing villus surface. The predicted optimal villi density 0.47±0.06 is compatible to previous experimental measurements. Several other ways to experimentally validate the model are also proposed. The proposed stream-tube model can serve as a basis for analyzing the efficiency of human placentas, detecting possible pathologies and diagnosing placental health risks for newborns by using routine histology sections collected after birth. Copyright © 2014 Elsevier Ltd. All rights reserved.

Modifications to the streamtube curvature program. Volume 1: Program modifications and user's manual. [user manuals (computer programs) for transonic flow of nacelles and intake systems of turbofan engines

NASA Technical Reports Server (NTRS)

Ferguson, D. R.; Keith, J. S.

1975-01-01

The improvements which have been incorporated in the Streamtube Curvature Program to enhance both its computational and diagnostic capabilities are described. Detailed descriptions are given of the revisions incorporated to more reliably handle the jet stream-external flow interaction at trailing edges. Also presented are the augmented boundary layer procedures and a variety of other program changes relating to program diagnostics and extended solution capabilities. An updated User's Manual, that includes information on the computer program operation, usage, and logical structure, is presented. User documentation includes an outline of the general logical flow of the program and detailed instructions for program usage and operation. From the standpoint of the programmer, the overlay structure is described. The input data, output formats, and diagnostic printouts are covered in detail and illustrated with three typical test cases.

Counter-rotating vortex pairs in the wake of a vertical axis wind turbine

NASA Astrophysics Data System (ADS)

Rolin, Vincent; Porté-Agel, Fernando

2017-04-01

Despite the rising popularity of vertical axis wind turbines, or VAWTs, the wakes behind these machines is much less well understood than those behind horizontal axis wind turbines, or HAWTs. A thorough understanding of wakes is important as they can cause turbines in wind farms to produce less power than anticipated and increase the fatigue loading on turbines due to vibrations. In order to gain a deeper understanding of the wake behind a vertical axis wind turbine in atmospheric flow stereo-PIV is implemented in a boundary-layer wind tunnel to produce snapshots of the 3-component velocity field in the wake at various downstream positions. The boundaries of the wake are readily observed due to the high velocity gradients and turbulence present here. Two pairs of counter-rotating vortices similar to those in the wake of yawed HAWTs are also observed. An examination of the momentum fluxes behind the turbine demonstrates that the mean flow induced by these vortices entrains a large quantity of momentum from the unperturbed boundary layer flow above the wake. This effect proves to play an even more significant role than turbulence in reintroducing momentum into the wake. In order to comprehend why the VAWT produces these vortices we modify the double-multiple stream-tube model typically used to predict VAWT performance to incorporate crosswind forces. The similarity between VAWT and yawed HAWT wakes is found not to be coincidental as both cases feature rotors which exert a lateral thrust on the incoming wind which leads to the creation of counter-rotating vortex pairs.

Micro-positron emission tomography for measuring sub-core scale single and multiphase transport parameters in porous media

NASA Astrophysics Data System (ADS)

Zahasky, Christopher; Benson, Sally M.

2018-05-01

Accurate descriptions of heterogeneity in porous media are important for understanding and modeling single phase (e.g. contaminant transport, saltwater intrusion) and multiphase (e.g. geologic carbon storage, enhanced oil recovery) transport problems. Application of medical imaging to experimentally quantify these processes has led to significant progress in material characterization and understanding fluid transport behavior at laboratory scales. While widely utilized in cancer diagnosis and management, cardiology, and neurology, positron emission tomography (PET) has had relatively limited applications in earth science. This study utilizes a small-bore micro-PET scanner to image and quantify the transport behavior of pulses of a conservative aqueous radiotracer injected during single and multiphase flow experiments in two heterogeneous Berea sandstone cores. The cores are discretized into axial-parallel streamtubes, and using the reconstructed micro-PET data, expressions are derived from spatial moment analysis for calculating sub-core tracer flux and pore water velocity. Using the flux and velocity measurements, it is possible to calculate porosity and saturation from volumetric flux balance, and calculate permeability and water relative permeability from Darcy's law. Second spatial moment analysis enables measurement of sub-core solute dispersion during both single phase and multiphase experiments. A numerical simulation model is developed to verify the assumptions of the streamtube dimension reduction technique. A variation of the reactor ratio is presented as a diagnostic metric to efficiently determine the validity of the streamtube approximation in core and column-scale experiments. This study introduces a new method to quantify sub-core permeability, relative permeability, and dispersion. These experimental and analytical methods provide a foundation for future work on experimental measurements of differences in transport behavior across scales.

Sub-core permeability and relative permeability characterization with Positron Emission Tomography

NASA Astrophysics Data System (ADS)

Zahasky, C.; Benson, S. M.

2017-12-01

This study utilizes preclinical micro-Positron Emission Tomography (PET) to image and quantify the transport behavior of pulses of a conservative aqueous radiotracer injected during single and multiphase flow experiments in a Berea sandstone core with axial parallel bedding heterogeneity. The core is discretized into streamtubes, and using the micro-PET data, expressions are derived from spatial moment analysis for calculating sub-core scale tracer flux and pore water velocity. Using the flux and velocity data, it is then possible to calculate porosity and saturation from volumetric flux balance, and calculate permeability and water relative permeability from Darcy's law. Full 3D simulations are then constructed based on this core characterization. Simulation results are compared with experimental results in order to test the assumptions of the simple streamtube model. Errors and limitations of this analysis will be discussed. These new methods of imaging and sub-core permeability and relative permeability measurements enable experimental quantification of transport behavior across scales.

STC-SAB program users manual for the turbulent boundary layer and turbulent separation prediction methods employed in the NASA Langley streamtube curvature computer program

NASA Technical Reports Server (NTRS)

Ferguson, D. R.

1972-01-01

The streamtube curvature program (STC) has been developed to predict the inviscid flow field and the pressure distribution about nacelles at transonic speeds. The effects of boundary layer are to displace the inviscid flow and effectively change the body shape. Thus, the body shape must be corrected by the displacement thickness in order to calculate the correct pressure distribution. This report describes the coupling of the Stratford and Beavers boundary layer solution with the inviscid STC analysis so that all nacelle pressure forces, friction drag, and incipient separation may be predicted. The usage of the coupled STC-SAB computer program is outlined and the program input and output are defined. Included in this manual are descriptions of the principal boundary layer tables and other revisions to the STC program. The use of the viscous option is controlled by the engineer during program input definition.

Analytical study of laser supported combustion waves in hydrogen

NASA Technical Reports Server (NTRS)

Kemp, N. H.; Root, R. G.

1977-01-01

A one-dimensional energy equation, with constant pressure and area, was used to model the LSC wave. This equation balances convection, conduction, laser energy absorption, radiation energy loss and radiation energy transport. Solutions of this energy equation were obtained to give profiles of temperature and other properties, as well as the relation between laser intensity and mass flux through the wave. The flow through the LSC wave was then conducted through a variable pressure, variable area streamtube to accelerate it to high speed, with the propulsion application in mind. A numerical method for coupling the LSC wave model to the streamtube flow was developed, and a sample calculation was performed. The result shows that 42% of the laser power has been radiated away by the time the gas reaches the throat. It was concluded that in the radially confined flows of interest for propulsion applications, transverse velocities would be less important than in the unconfined flows where air experiments have been conducted.

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

Ahedo, Eduardo; Merino, Mario

A previous axisymmetric model of the supersonic expansion of a collisionless, hot plasma in a divergent magnetic nozzle is extended here in order to include electron-inertia effects. Up to dominant order on all components of the electron velocity, electron momentum equations still reduce to three conservation laws. Electron inertia leads to outward electron separation from the magnetic streamtubes. The progressive plasma filling of the adjacent vacuum region is consistent with electron-inertia being part of finite electron Larmor radius effects, which increase downstream and eventually demagnetize the plasma. Current ambipolarity is not fulfilled and ion separation can be either outwards ormore » inwards of magnetic streamtubes, depending on their magnetization. Electron separation penalizes slightly the plume efficiency and is larger for plasma beams injected with large pressure gradients. An alternative nonzero electron-inertia model [E. Hooper, J. Propul. Power 9, 757 (1993)] based on cold plasmas and current ambipolarity, which predicts inwards electron separation, is discussed critically. A possible competition of the gyroviscous force with electron-inertia effects is commented briefly.« less

Splash flow from a metal plate hit by an electron beam pulse

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

Garcia, M., LLNL

1997-09-01

When a pulsed electron beam hits a metal plate with sufficient energy a volume of the metal becomes hot fluid that subsequently sprays out of the plate. A second pulse of electrons traveling toward the plate would scatter and degrade before impacting the solid plate because of its encounter with the diffuse material of the initial splash. People designing electron beam machines for use as pulsed radiation sources wish to eliminate the interaction between the electrons and the splash because they want sharp radiation pulses emitted from the solid plate. This report presents a compressible fluid model of this splashmore » flow and compares specific cases with experiments and comprehensive calculations performed by B. DeVolder and others at the Los Alamos National Laboratory, see reference (1). My aim was to develop as simple a theory as possible to calculate the speed and density of the splash flow. I have used both simplifying assumptions and mathematical approximations to develop convenient formulas. As I wished to make a clear and interesting presentation of this work to a diverse audience that includes people outside the specialty of fluid dynamics, some of my descriptions may seem wordier than necessary. The plan of the report is as follows. In the section called ``energy deposition`` I describe how an electron beam deposits energy in a solid plate, converting some of the material into a hot fluid. The initial temperature of this fluid is the key parameter in determining the nature of the subsequent flow; an explicit formula is shown. Flow occurs in two regions: along a streamtube within the metal plate and as an expanding plume outside the metal plate. Flow within the plate is described in the section called ``isentropic flow.`` This flow occurs as expansion waves move at the speed of sound through the streamtube. The analysis of this flow provides a formula for the mass flow over time from the plate into the external splash. The section called ``centered expansion`` elaborates on the nature of certain approximations I have made in treating the wave phenomena in both the streamtube and splash flows. The section called ``splash flow`` presents a formula to describe the material density as a function of space and time outside the plate. This formula depends on the time- dependent material density at the plate, which was found during the streamtube analysis. The section called ``examples`` shows the results of specific calculations and a comparison to computational and experimental results described in reference (1). The final section, ``possible future work,`` poses new questions.« less

Traveltime-based descriptions of transport and mixing in heterogeneous domains

NASA Astrophysics Data System (ADS)

Luo, Jian; Cirpka, Olaf A.

2008-09-01

Modeling mixing-controlled reactive transport using traditional spatial discretization of the domain requires identifying the spatial distributions of hydraulic and reactive parameters including mixing-related quantities such as dispersivities and kinetic mass transfer coefficients. In most applications, breakthrough curves (BTCs) of conservative and reactive compounds are measured at only a few locations and spatially explicit models are calibrated by matching these BTCs. A common difficulty in such applications is that the individual BTCs differ too strongly to justify the assumption of spatial homogeneity, whereas the number of observation points is too small to identify the spatial distribution of the decisive parameters. The key objective of the current study is to characterize physical transport by the analysis of conservative tracer BTCs and predict the macroscopic BTCs of compounds that react upon mixing from the interpretation of conservative tracer BTCs and reactive parameters determined in the laboratory. We do this in the framework of traveltime-based transport models which do not require spatially explicit, costly aquifer characterization. By considering BTCs of a conservative tracer measured on different scales, one can distinguish between mixing, which is a prerequisite for reactions, and spreading, which per se does not foster reactions. In the traveltime-based framework, the BTC of a solute crossing an observation plane, or ending in a well, is interpreted as the weighted average of concentrations in an ensemble of non-interacting streamtubes, each of which is characterized by a distinct traveltime value. Mixing is described by longitudinal dispersion and/or kinetic mass transfer along individual streamtubes, whereas spreading is characterized by the distribution of traveltimes, which also determines the weights associated with each stream tube. Key issues in using the traveltime-based framework include the description of mixing mechanisms and the estimation of the traveltime distribution. In this work, we account for both apparent longitudinal dispersion and kinetic mass transfer as mixing mechanisms, thus generalizing the stochastic-convective model with or without inter-phase mass transfer and the advective-dispersive streamtube model. We present a nonparametric approach of determining the traveltime distribution, given a BTC integrated over an observation plane and estimated mixing parameters. The latter approach is superior to fitting parametric models in cases wherein the true traveltime distribution exhibits multiple peaks or long tails. It is demonstrated that there is freedom for the combinations of mixing parameters and traveltime distributions to fit conservative BTCs and describe the tailing. A reactive transport case of a dual Michaelis-Menten problem demonstrates that the reactive mixing introduced by local dispersion and mass transfer may be described by apparent mean mass transfer with coefficients evaluated by local BTCs.

Classic Bernoulli's Principle Derivation and Its Working Hypotheses

ERIC Educational Resources Information Center

Marciotto, Edson R.

2016-01-01

The Bernoulli's principle states that the quantity p+ pgz + pv[superscript 2]/2 must be conserved in a streamtube if some conditions are matched, namely: steady and irrotational flow of an inviscid and incompressible fluid. In most physics textbooks this result is demonstrated invoking the energy conservation of a fluid material volume at two…

An inverse inviscid method for the design of quasi-three dimensional rotating turbomachinery cascades

NASA Technical Reports Server (NTRS)

Bonataki, E.; Chaviaropoulos, P.; Papailiou, K. D.

1991-01-01

A new inverse inviscid method suitable for the design of rotating blade sections lying on an arbitrary axisymmetric stream-surface with varying streamtube width is presented. The geometry of the axisymmetric stream-surface and the streamtube width variation with meridional distance, the number of blades, the inlet flow conditions, the rotational speed and the suction and pressure side velocity distributions as functions of the normalized arc-length are given. The flow is considered irrotational in the absolute frame of reference and compressible. The output of the computation is the blade section that satisfies the above data. The method solves the flow equations on a (phi 1, psi) potential function-streamfunction plane for the velocity modulus, W and the flow angle beta; the blade section shape can then be obtained as part of the physical plane geometry by integrating the flow angle distribution along streamlines. The (phi 1, psi) plane is defined so that the monotonic behavior of the potential function is guaranteed, even in cases with high peripheral velocities. The method is validated on a rotating turbine case and used to design new blades. To obtain a closed blade, a set of closure conditions were developed and referred.

Panel method for the wake effects on the aerodynamics of vertical-axis wind turbines

NASA Astrophysics Data System (ADS)

Goyal, Udit; Rempfer, Dietmar

2011-11-01

A formulation based on the panel method is implemented for studying the unsteady aerodynamics of straight-bladed vertical-axis wind turbines. A combination of source and vortex distributions is used to represent an airfoil in Darrieus type motion. Our approach represents a low-cost computational technique that takes into account the dynamic changes in angle of attack of the blade during a cycle. A time-stepping mechanism is introduced for the wake convection, and its effects on the aerodynamic forces on the blade are discussed. The focus of the study is to describe the effect of the trailing wakes on the upstream flow conditions and coefficient of performance of the turbines. Results show a decrease in Cp until the wake structure develops and assumes a quasi-steady behavior. A comparison with other models such as single and multiple streamtubes is discussed, and optimization of the blade pitch angle is performed to increase the instantaneous torque and hence the power output from the turbine.

Optimization of blade motion of vertical axis turbine

NASA Astrophysics Data System (ADS)

Ma, Yong; Zhang, Liang; Zhang, Zhi-yang; Han, Duan-feng

2016-04-01

In this paper, a method is proposed to improve the energy efficiency of the vertical axis turbine. First of all, a single disk multiple stream-tube model is used to calculate individual fitness. Genetic algorithm is adopted to optimize blade pitch motion of vertical axis turbine with the maximum energy efficiency being selected as the optimization objective. Then, a particular data processing method is proposed, fitting the result data into a cosine-like curve. After that, a general formula calculating the blade motion is developed. Finally, CFD simulation is used to validate the blade pitch motion formula. The results show that the turbine's energy efficiency becomes higher after the optimization of blade pitch motion; compared with the fixed pitch turbine, the efficiency of variable-pitch turbine is significantly improved by the active blade pitch control; the energy efficiency declines gradually with the growth of speed ratio; besides, compactness has lager effect on the blade motion while the number of blades has little effect on it.

The 13-inch magnetic suspension and balance system wind tunnel

NASA Technical Reports Server (NTRS)

Johnson, William G., Jr.; Dress, David A.

1989-01-01

NASA Langley has a small, subsonic wind tunnel in use with the 13-inch Magnetic Suspension and Balance System (MSBS). The tunnel is capable of speeds up to Mach 0.5. This report presents tunnel design and construction details. It includes flow uniformity, angularity, and velocity fluctuation data. It also compares experimental Mach number distribution data with computed results for the General Electric Streamtube Curvature Program.

Propulsion and Energetics Panel Working Group 12 on through Flow Calculations in Axial Turbomachines

DTIC Science & Technology

1981-10-01

Determination of the trends of the effect of variables such as streamtube thickness and streamline change of radius in rotors , chordwise losses and turning...prediction which occur near the end walls (particularly at the rotor root) are typical of the effects of secondary flow. They result in large discrepancies...0.4 y/h 0.6 08 1.0 Fig.4.9 Hannover turbine effect of loss distribution at rotor exit L . -k" i ... ... .. . . .. 48 DEVIATION AOL I 26 Iy Fig.4.10

A local-circulation model for Darrieus vertical-axis wind turbines

NASA Astrophysics Data System (ADS)

Masse, B.

1986-04-01

A new computational model for the aerodynamics of the vertical-axis wind turbine is presented. Based on the local-circulation method generalized for curved blades, combined with a wake model for the vertical-axis wind turbine, it differs markedly from current models based on variations in the streamtube momentum and vortex models using the lifting-line theory. A computer code has been developed to calculate the loads and performance of the Darrieus vertical-axis wind turbine. The results show good agreement with experimental data and compare well with other methods.

Numerical Modeling of Three-Dimensional Confined Flows

NASA Technical Reports Server (NTRS)

Greywall, M. S.

1981-01-01

A three dimensional confined flow model is presented. The flow field is computed by calculating velocity and enthalpy along a set of streamlines. The finite difference equations are obtained by applying conservation principles to streamtubes constructed around the chosen streamlines. With appropriate substitutions for the body force terms, the approach computes three dimensional magnetohydrodynamic channel flows. A listing of a computer code, based on this approach is presented in FORTRAN IV language. The code computes three dimensional compressible viscous flow through a rectangular duct, with the duct cross section specified along the axis.

Characterizations of double pulsing in neutron multiplicity and coincidence counting systems

DOE PAGES

Koehler, Katrina E.; Henzl, Vladimir; Croft, Stephen; ...

2016-06-29

Passive neutron coincidence/multiplicity counters are subject to non-ideal behavior, such as double pulsing and dead time. It has been shown in the past that double-pulsing exhibits a distinct signature in a Rossi-alpha distribution, which is not readily noticed using traditional Multiplicity Shift Register analysis. But, it has been assumed that the use of a pre-delay in shift register analysis removes any effects of double pulsing. Here, we use high-fidelity simulations accompanied by experimental measurements to study the effects of double pulsing on multiplicity rates. By exploiting the information from the double pulsing signature peak observable in the Rossi-alpha distribution, themore » double pulsing fraction can be determined. Algebraic correction factors for the multiplicity rates in terms of the double pulsing fraction have been developed. We also discuss the role of these corrections across a range of scenarios.« less

Quantum Double of Yangian of strange Lie superalgebra Qn and multiplicative formula for universal R-matrix

NASA Astrophysics Data System (ADS)

Stukopin, Vladimir

2018-02-01

Main result is the multiplicative formula for universal R-matrix for Quantum Double of Yangian of strange Lie superalgebra Qn type. We introduce the Quantum Double of the Yangian of the strange Lie superalgebra Qn and define its PBW basis. We compute the Hopf pairing for the generators of the Yangian Double. From the Hopf pairing formulas we derive a factorized multiplicative formula for the universal R-matrix of the Yangian Double of the Lie superalgebra Qn . After them we obtain coefficients in this multiplicative formula for universal R-matrix.

A scrutiny of heterogeneity at the TCE Source Area BioREmediation (SABRE) test site

NASA Astrophysics Data System (ADS)

Rivett, M.; Wealthall, G. P.; Mcmillan, L. A.; Zeeb, P.

2015-12-01

A scrutiny of heterogeneity at the UK's Source Area BioREmediation (SABRE) test site is presented to better understand how spatial heterogeneity in subsurface properties and process occurrence may constrain performance of enhanced in-situ bioremediation (EISB). The industrial site contained a 25 to 45 year old trichloroethene (TCE) dense non-aqueous phase liquid (DNAPL) that was exceptionally well monitored via a network of multilevel samplers and high resolution core sampling. Moreover, monitoring was conducted within a 3-sided sheet-pile cell that allowed a controlled streamtube of flow to be drawn through the source zone by an extraction well. We primarily focus on the longitudinal transect of monitoring along the length of the cell that provides a 200 groundwater point sample slice along the streamtube of flow through the DNAPL source zone. TCE dechlorination is shown to be significant throughout the cell domain, but spatially heterogeneous in occurrence and progress of dechlorination to lesser chlorinated ethenes - it is this heterogeneity in dechlorination that we primarily scrutinise. We illustrate the diagnostic use of the relative occurrence of TCE parent and daughter compounds to confirm: dechlorination in close proximity to DNAPL and enhanced during the bioremediation; persistent layers of DNAPL into which gradients of dechlorination products are evident; fast flowpaths through the source zone where dechlorination is less evident; and, the importance of underpinning flow regime understanding on EISB performance. Still, even with such spatial detail, there remains uncertainty over the dataset interpretation. These includes poor closure of mass balance along the cell length for the multilevel sampler based monitoring and points to needs to still understand lateral flows (even in the constrained cell), even greater spatial resolution of point monitoring and potentially, not easily proven, ethene degradation loss.

Faster Double-Size Bipartite Multiplication out of Montgomery Multipliers

NASA Astrophysics Data System (ADS)

Yoshino, Masayuki; Okeya, Katsuyuki; Vuillaume, Camille

This paper proposes novel algorithms for computing double-size modular multiplications with few modulus-dependent precomputations. Low-end devices such as smartcards are usually equipped with hardware Montgomery multipliers. However, due to progresses of mathematical attacks, security institutions such as NIST have steadily demanded longer bit-lengths for public-key cryptography, making the multipliers quickly obsolete. In an attempt to extend the lifespan of such multipliers, double-size techniques compute modular multiplications with twice the bit-length of the multipliers. Techniques are known for extending the bit-length of classical Euclidean multipliers, of Montgomery multipliers and the combination thereof, namely bipartite multipliers. However, unlike classical and bipartite multiplications, Montgomery multiplications involve modulus-dependent precomputations, which amount to a large part of an RSA encryption or signature verification. The proposed double-size technique simulates double-size multiplications based on single-size Montgomery multipliers, and yet precomputations are essentially free: in an 2048-bit RSA encryption or signature verification with public exponent e=216+1, the proposal with a 1024-bit Montgomery multiplier is at least 1.5 times faster than previous double-size Montgomery multiplications.

LOX/hydrocarbon fuel carbon formation and mixing data analysis

NASA Technical Reports Server (NTRS)

Fang, J.

1983-01-01

By applying the Priem-Heidmann Generalized-Length vaporization correlation, the computer model developed by the present study predicts the spatial variation of propellant vaporization rate using the injector cold flow results to define the streamtubes. The calculations show that the overall and local propellant vaporization rate and mixture ratio change drastically as the injection element type or the injector operating condition is changed. These results are compared with the regions of carbon formation observed in the photographic combustion testing. The correlation shows that the fuel vaporization rate and the local mixture ratio produced by the injector element have first order effects on the degree of carbon formation.

Dynamics of multiple double layers in high pressure glow discharge in a simple torus

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

Kumar Paul, Manash, E-mail: manashkr@gmail.com; Sharma, P. K.; Thakur, A.

2014-06-15

Parametric characterization of multiple double layers is done during high pressure glow discharge in a toroidal vessel of small aspect ratio. Although glow discharge (without magnetic field) is known to be independent of device geometry, but the toroidal boundary conditions are conducive to plasma growth and eventually the plasma occupy the toroidal volume partially. At higher anode potential, the visibly glowing spots on the body of spatially extended anode transform into multiple intensely luminous spherical plasma blob structures attached to the tip of the positive electrode. Dynamics of multiple double layers are observed in argon glow discharge plasma in presencemore » of toroidal magnetic field. The radial profiles of plasma parameters measured at various toroidal locations show signatures of double layer formation in our system. Parametric dependence of double layer dynamics in presence of toroidal magnetic field is presented here.« less

Double Cross-Validation in Multiple Regression: A Method of Estimating the Stability of Results.

ERIC Educational Resources Information Center

Rowell, R. Kevin

In multiple regression analysis, where resulting predictive equation effectiveness is subject to shrinkage, it is especially important to evaluate result replicability. Double cross-validation is an empirical method by which an estimate of invariance or stability can be obtained from research data. A procedure for double cross-validation is…

Transition from single to multiple double layers. [of plasma

NASA Technical Reports Server (NTRS)

Chan, C.; Hershkowitz, N.

1982-01-01

Laboratory results are presented to define parameters which allow the boundary conditions to control the characteristics of double layers of plasma. It is shown that multiple double layers arise when the ratio of Debye length to system length decreases, a result which is in line with boundary layer theory. The significance of inclusion of the system length is noted to render BGK treatments of double layers, wherein the length is neglected, invalid.

Field-scale Prediction of Enhanced DNAPL Dissolution Using Partitioning Tracers and Flow Pattern Effects

NASA Astrophysics Data System (ADS)

Wang, F.; Annable, M. D.; Jawitz, J. W.

2012-12-01

The equilibrium streamtube model (EST) has demonstrated the ability to accurately predict dense nonaqueous phase liquid (DNAPL) dissolution in laboratory experiments and numerical simulations. Here the model is applied to predict DNAPL dissolution at a PCE-contaminated dry cleaner site, located in Jacksonville, Florida. The EST is an analytical solution with field-measurable input parameters. Here, measured data from a field-scale partitioning tracer test were used to parameterize the EST model and the predicted PCE dissolution was compared to measured data from an in-situ alcohol (ethanol) flood. In addition, a simulated partitioning tracer test from a calibrated spatially explicit multiphase flow model (UTCHEM) was also used to parameterize the EST analytical solution. The ethanol prediction based on both the field partitioning tracer test and the UTCHEM tracer test simulation closely matched the field data. The PCE EST prediction showed a peak shift to an earlier arrival time that was concluded to be caused by well screen interval differences between the field tracer test and alcohol flood. This observation was based on a modeling assessment of potential factors that may influence predictions by using UTCHEM simulations. The imposed injection and pumping flow pattern at this site for both the partitioning tracer test and alcohol flood was more complex than the natural gradient flow pattern (NGFP). Both the EST model and UTCHEM were also used to predict PCE dissolution under natural gradient conditions, with much simpler flow patterns than the forced-gradient double five spot of the alcohol flood. The NGFP predictions based on parameters determined from tracer tests conducted with complex flow patterns underestimated PCE concentrations and total mass removal. This suggests that the flow patterns influence aqueous dissolution and that the aqueous dissolution under the NGFP is more efficient than dissolution under complex flow patterns.

Double bevel construction of a diamond anvil

DOEpatents

Moss, W.C.

1988-10-11

A double or multiple bevel culet geometry is used on a diamond anvil in a high pressure cell apparatus to provide increased sample pressure and stability for a given force applied to the diamond tables. Double or multiple bevel culet geometries can also be used for sapphire or other hard crystal anvils. Pressures up to and above 5 Megabars can be reached. 8 figs.

Double bevel construction of a diamond anvil

DOEpatents

Moss, William C.

1988-01-01

A double or multiple bevel culet geometry is used on a diamond anvil in a high pressure cell apparatus to provide increased sample pressure and stability for a given force applied to the diamond tables. Double or multiple bevel culet geometries can also be used for sapphire or other hard crystal anvils. Pressures up to and above 5 Megabars can be reached.

Laboratory observation of multiple double layer resembling space plasma double layer

NASA Astrophysics Data System (ADS)

Alex, Prince; Arumugam, Saravanan; Sinha, Suraj

2017-10-01

Perceptible double layer consisting of more than one layers were produced in laboratory using a double discharge plasma setup. The confinement of oppositely charged particles in each layer with sharply defined luminous boarder is attributed to the self-organization scenario. This structure is generated in front of a positively biased electrode when the electron drift velocity (νd) exceeds 1.3 times the electron thermal velocity (νte) . Stable multiple double layer structures were observed only between 1.3 νte <=νd <= 3 νte. At νd = 1.3 νte, oscillations were excited in the form of large amplitude burst followed by a high frequency stable oscillation. Beyond νd = 3 νte, multiple double layer begins to collapse which is characterized by an emergence in turbulence. Long range dependence in the corresponding electrostatic potential fluctuations indicates the role of self-organized criticality in the emergence of turbulence. The algebraic decaying tale of the autocorrelation function and power law behavior in the power spectrum are consistent with the observation.

Effect of multiple plasmon excitation on single, double and multiple ionizations of C60 in collisions with fast highly charged Si ions

NASA Astrophysics Data System (ADS)

Kelkar, A. H.; Kadhane, U.; Misra, D.; Kumar, A.; Tribedi, L. C.

2007-06-01

We have investigated the single and multiple ionizations of the C60 molecule in collisions with fast Siq+ projectiles for various projectile charge states (q) between q = 6 and 14. The q-dependence of the ionization cross sections and their ratios is compared with the giant dipole plasmon resonance (GDPR) model. The excellent qualitative agreement with the model in case of single and double ionizations and also a reasonable agreement with the triple (and to some extent with quadruple) ionization (without evaporation) yields signify dominant contributions of the single-, double- and triple-plasmon excitations on the single- and multiple-ionization process.

Single, double or multiple-injection techniques for non-ultrasound guided axillary brachial plexus block in adults undergoing surgery of the lower arm.

PubMed

Chin, Ki Jinn; Alakkad, Husni; Cubillos, Javier E

2013-08-08

Regional anaesthesia comprising axillary block of the brachial plexus is a common anaesthetic technique for distal upper limb surgery. This is an update of a review first published in 2006 and updated in 2011. To compare the relative effects (benefits and harms) of three injection techniques (single, double and multiple) of axillary block of the brachial plexus for distal upper extremity surgery. We considered these effects primarily in terms of anaesthetic effectiveness; the complication rate (neurological and vascular); and pain and discomfort caused by performance of the block. We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library), MEDLINE, EMBASE and reference lists of trials. We contacted trial authors. The date of the last search was March 2013 (updated from March 2011). We included randomized controlled trials that compared double with single-injection techniques, multiple with single-injection techniques, or multiple with double-injection techniques for axillary block in adults undergoing surgery of the distal upper limb. We excluded trials using ultrasound-guided techniques. Independent study selection, risk of bias assessment and data extraction were performed by at least two investigators. We undertook meta-analysis. The 21 included trials involved a total of 2148 participants who received regional anaesthesia for hand, wrist, forearm or elbow surgery. Risk of bias assessment indicated that trial design and conduct were generally adequate; the most common areas of weakness were in blinding and allocation concealment.Eight trials comparing double versus single injections showed a statistically significant decrease in primary anaesthesia failure (risk ratio (RR 0.51), 95% confidence interval (CI) 0.30 to 0.85). Subgroup analysis by method of nerve location showed that the effect size was greater when neurostimulation was used rather than the transarterial technique.Eight trials comparing multiple with single injections showed a statistically significant decrease in primary anaesthesia failure (RR 0.25, 95% CI 0.14 to 0.44) and of incomplete motor block (RR 0.61, 95% CI 0.39 to 0.96) in the multiple injection group.Eleven trials comparing multiple with double injections showed a statistically significant decrease in primary anaesthesia failure (RR 0.28, 95% CI 0.20 to 0.40) and of incomplete motor block (RR 0.55, 95% CI 0.36 to 0.85) in the multiple injection group.Tourniquet pain was significantly reduced with multiple injections compared with double injections (RR 0.53, 95% CI 0.33 to 0.84). Otherwise there were no statistically significant differences between groups in any of the three comparisons on secondary analgesia failure, complications and patient discomfort. The time for block performance was significantly shorter for single and double injections compared with multiple injections. This review provides evidence that multiple-injection techniques using nerve stimulation for axillary plexus block produce more effective anaesthesia than either double or single-injection techniques. However, there was insufficient evidence for a significant difference in other outcomes, including safety.

Double Star Measurements at the Internationale Amateur Sternwarte (IAS) in Namibia in 2008 and 2009

NASA Astrophysics Data System (ADS)

Anton, Rainer

2010-04-01

A 40-cm-Cassegrain telescope in Namibia was used for observing double and multiple systems in the southern sky. Digital images were recorded with a CCD camera at high frame rates via a firewire interface directly in a computer. Measurements of 34 double and multiple systems are presented and compared with literature data. Some noteworthy objects are discussed in more detail.

Heat transfer in rocket engine combustion chambers and regeneratively cooled nozzles

NASA Technical Reports Server (NTRS)

1993-01-01

A conjugate heat transfer computational fluid dynamics (CFD) model to describe regenerative cooling in the main combustion chamber and nozzle and in the injector faceplate region for a launch vehicle class liquid rocket engine was developed. An injector model for sprays which treats the fluid as a variable density, single-phase media was formulated, incorporated into a version of the FDNS code, and used to simulate the injector flow typical of that in the Space Shuttle Main Engine (SSME). Various chamber related heat transfer analyses were made to verify the predictive capability of the conjugate heat transfer analysis provided by the FDNS code. The density based version of the FDNS code with the real fluid property models developed was successful in predicting the streamtube combustion of individual injector elements.

ADAM: An Axisymmetric Duct Aeroacoustic Modeling system. [aircraft turbofan engines

NASA Technical Reports Server (NTRS)

Abrahamson, A. L.

1983-01-01

An interconnected system of computer programs for analyzing the propagation and attenuation of sound in aeroengine ducts containing realistic compressible subsonic mean flows, ADAM was developed primarily for research directed towards the reduction of noise emitted from turbofan aircraft engines. The two basic components are a streamtube curvature program for determination of the mean flow, and a finite element code for solution of the acoustic propagation problem. The system, which has been specifically tailored for ease of use, is presently installed at NASA Langley Reseach Center on a Control Data Cyber 175 Computer under the NOS Operating system employing a Tektronix terminal for interactive graphics. The scope and organization of the ADAM system is described. A users guide, examples of input data, and results for selected cases are included.

Auralization of CFD Vorticity Using an Auditory Illusion

NASA Astrophysics Data System (ADS)

Volpe, C. R.

2005-12-01

One way in which scientists and engineers interpret large quantities of data is through a process called visualization, i.e. generating graphical images that capture essential characteristics and highlight interesting relationships. Another approach, which has received far less attention, is to present complex information with sound. This approach, called ``auralization" or ``sonification", is the auditory analog of visualization. Early work in data auralization frequently involved directly mapping some variable in the data to a sound parameter, such as pitch or volume. Multi-variate data could be auralized by mapping several variables to several sound parameters simultaneously. A clear drawback of this approach is the limited practical range of sound parameters that can be presented to human listeners without exceeding their range of perception or comfort. A software auralization system built upon an existing visualization system is briefly described. This system incorporates an aural presentation synchronously and interactively with an animated scientific visualization, so that alternate auralization techniques can be investigated. One such alternate technique involves auditory illusions: sounds which trick the listener into perceiving something other than what is actually being presented. This software system will be used to present an auditory illusion, known for decades among cognitive psychologists, which produces a sound that seems to ascend or descend endlessly in pitch. The applicability of this illusion for presenting Computational Fluid Dynamics data will be demonstrated. CFD data is frequently visualized with thin stream-lines, but thicker stream-ribbons and stream-tubes can also be used, which rotate to convey fluid vorticity. But a purely graphical presentation can yield drawbacks of its own. Thicker stream-tubes can be self-obscuring, and can obscure other scene elements as well, thus motivating a different approach, such as using sound. Naturally, the simple approach of mapping clockwise and counterclockwise rotations to actual pitch increases and decreases, eventually results in sounds that the listener cannot hear. In this alternate presentation using an auditory illusion, repeated rotations of a stream-tube are replaced with continual increases or decreases in apparent pitch. These apparent pitch changes can continue without bound, yet never exceed the range of frequencies that the listener can hear. The effectiveness of this presentation technique has been studied, and empirical results, obtained through formal user testing and statistical analysis, are presented. These results demonstrate that an aural data presentation using an auditory illusion can improve performance in locating key data characteristics, a task that demonstrates a certain level of understanding of the data. The experiments show that this holds true even when the user expresses a subjective preference and greater confidence in a visual presentation. The CFD data used in the research comes from a number of different industrial domains, but the advantages of this technique could be equally applicable to the study of earth sciences involving fluid mechanics, such as atmospheric or ocean sciences. Furthermore, the approach is applicable not only to CFD data, but to any type of data in which a quantity that is cyclic in nature, such as orientation, needs to be presented. Although the techniques and tools were originally developed with scientists and engineers in mind, they can also be used to aid students, particularly those who are visually impaired or who have difficulty interpreting certain spatial relationships visually.

Transfer functions of double- and multiple-cavity Fabry-Perot filters driven by Lorentzian sources.

PubMed

Marti, J; Capmany, J

1996-12-20

We derive expressions for the transfer functions of double- and multiple-cavity Fabry-Perot filters driven by laser sources with Lorentzian spectrum. These are of interest because of their applications in sensing and channel filtering in optical frequency-division multiplexing networks.

Transfer functions of double- and multiple-cavity Fabry Perot filters driven by Lorentzian sources

NASA Astrophysics Data System (ADS)

Marti, Javier; Capmany, Jose

1996-12-01

We derive expressions for the transfer functions of double- and multiple-cavity Fabry Perot filters driven by laser sources with Lorentzian spectrum. These are of interest because of their applications in sensing and channel filtering in optical frequency-division multiplexing networks.

Multiple and configurable optical logic systems based on layered double hydroxides and chromophore assemblies.

PubMed

Shi, Wenying; Fu, Yi; Li, Zhixiong; Wei, Min

2015-01-14

Multiple and configurable fluorescence logic gates were fabricated via self-assembly of layered double hydroxides and various chromophores. These logic gates were operated by observation of different emissions with the same excitation wavelength, which achieve YES, NOT, AND, INH and INHIBIT logic operations, respectively.

A practical theoretical formalism for atomic multielectron processes: direct multiple ionization by a single auger decay or by impact of a single electron or photon

NASA Astrophysics Data System (ADS)

Liu, Pengfei; Zeng, Jiaolong; Yuan, Jianmin

2018-04-01

Multiple electron processes occur widely in atoms, molecules, clusters, and condensed matters when they are interacting with energetic particles or intense laser fields. Direct multielectron processes (DMEP) are the most complicated among the general multiple electron processes and are the most difficult to describe theoretically. In this work, a unified and accurate theoretical formalism is proposed on the DMEP of atoms including the multiple auger decay and multiple ionization by an impact of a single electron or a single photon based on the atomic collision theory described by a correlated many-body Green's function. Such a practical treatment is made possible by taking consideration of the different coherence features of the atoms (matter waves) in the initial and final states. We first explain how the coherence characteristics of the ejected continuum electrons is largely destructed, by taking the electron impact direct double ionization process as an example. The direct double ionization process is completely different from the single ionization where the complete interference can be maintained. The detailed expressions are obtained for the energy correlations among the continuum electrons and energy resolved differential and integral cross sections according to the separation of knock-out (KO) and shake-off (SO) mechanisms for the electron impact direct double ionization, direct double and triple auger decay, and double and triple photoionization (TPI) processes. Extension to higher order DMEP than triple ionization is straight forward by adding contributions of the following KO and SO processes. The approach is applied to investigate the electron impact double ionization processes of C+, N+, and O+, the direct double and triple auger decay of the K-shell excited states of C+ 1s2{s}22{p}2{}2D and {}2P, and the double and TPI of lithium. Comparisons with the experimental and other theoretical investigations wherever available in the literature show that our theoretical formalism is accurate and effective in treating the atomic multielectron processes.

Double-Pulsed 2-micron Laser Transmitter for Multiple Lidar Applications

NASA Technical Reports Server (NTRS)

Singh, Upendra N.; Yu, Jirong

2002-01-01

A high energy double-pulsed Ho:Tm:YLF 2-micron laser amplifier has been demonstrated. 600 mJ per pulse pair under Q-switch operation is achieved with the gain of 4.4. This solid-state laser source can be used as lidar transmitter for multiple lidar applications such as coherent wind and carbon dioxide measurements.

Field-scale prediction of enhanced DNAPL dissolution based on partitioning tracers.

PubMed

Wang, Fang; Annable, Michael D; Jawitz, James W

2013-09-01

The equilibrium streamtube model (EST) has demonstrated the ability to accurately predict dense nonaqueous phase liquid (DNAPL) dissolution in laboratory experiments and numerical simulations. Here the model is applied to predict DNAPL dissolution at a tetrachloroethylene (PCE)-contaminated dry cleaner site, located in Jacksonville, Florida. The EST model is an analytical solution with field-measurable input parameters. Measured data from a field-scale partitioning tracer test were used to parameterize the EST model and the predicted PCE dissolution was compared to measured data from an in-situ ethanol flood. In addition, a simulated partitioning tracer test from a calibrated, three-dimensional, spatially explicit multiphase flow model (UTCHEM) was also used to parameterize the EST analytical solution. The EST ethanol prediction based on both the field partitioning tracer test and the simulation closely matched the total recovery well field ethanol data with Nash-Sutcliffe efficiency E=0.96 and 0.90, respectively. The EST PCE predictions showed a peak shift to earlier arrival times for models based on either field-measured or simulated partitioning tracer tests, resulting in poorer matches to the field PCE data in both cases. The peak shifts were concluded to be caused by well screen interval differences between the field tracer test and ethanol flood. Both the EST model and UTCHEM were also used to predict PCE aqueous dissolution under natural gradient conditions, which has a much less complex flow pattern than the forced-gradient double five spot used for the ethanol flood. The natural gradient EST predictions based on parameters determined from tracer tests conducted with a complex flow pattern underestimated the UTCHEM-simulated natural gradient total mass removal by 12% after 170 pore volumes of water flushing indicating that some mass was not detected by the tracers likely due to stagnation zones in the flow field. These findings highlight the important influence of well configuration and the associated flow patterns on dissolution. © 2013.

Field-scale prediction of enhanced DNAPL dissolution based on partitioning tracers

NASA Astrophysics Data System (ADS)

Wang, Fang; Annable, Michael D.; Jawitz, James W.

2013-09-01

The equilibrium streamtube model (EST) has demonstrated the ability to accurately predict dense nonaqueous phase liquid (DNAPL) dissolution in laboratory experiments and numerical simulations. Here the model is applied to predict DNAPL dissolution at a tetrachloroethylene (PCE)-contaminated dry cleaner site, located in Jacksonville, Florida. The EST model is an analytical solution with field-measurable input parameters. Measured data from a field-scale partitioning tracer test were used to parameterize the EST model and the predicted PCE dissolution was compared to measured data from an in-situ ethanol flood. In addition, a simulated partitioning tracer test from a calibrated, three-dimensional, spatially explicit multiphase flow model (UTCHEM) was also used to parameterize the EST analytical solution. The EST ethanol prediction based on both the field partitioning tracer test and the simulation closely matched the total recovery well field ethanol data with Nash-Sutcliffe efficiency E = 0.96 and 0.90, respectively. The EST PCE predictions showed a peak shift to earlier arrival times for models based on either field-measured or simulated partitioning tracer tests, resulting in poorer matches to the field PCE data in both cases. The peak shifts were concluded to be caused by well screen interval differences between the field tracer test and ethanol flood. Both the EST model and UTCHEM were also used to predict PCE aqueous dissolution under natural gradient conditions, which has a much less complex flow pattern than the forced-gradient double five spot used for the ethanol flood. The natural gradient EST predictions based on parameters determined from tracer tests conducted with a complex flow pattern underestimated the UTCHEM-simulated natural gradient total mass removal by 12% after 170 pore volumes of water flushing indicating that some mass was not detected by the tracers likely due to stagnation zones in the flow field. These findings highlight the important influence of well configuration and the associated flow patterns on dissolution.

Effect of interactions between multiple interfaces on the rheological characteristics of double emulsions

NASA Astrophysics Data System (ADS)

Choi, Se Bin; Park, Jae Yong; Moon, Ji Young; Lee, Joon Sang

2018-06-01

In this study, we analyzed the rheological characteristics of double emulsions by using a three-dimensional lattice Boltzmann model. Numerical simulations indicate that interactions between multiple interfaces play a vital role in determining the shear stress on interfaces and affect deformations, which influence the relative viscosity of double emulsions. The large shear stress induced by droplets in contact increases the relative viscosity for high volume fractions. The double emulsions also show shear-thinning behavior, which corresponds with the Carreau model. The interfacial interference between the core and the deforming shell cause the relative viscosity to increase with increasing core-droplet radius. Finally, we investigated the dependence of the double-emulsion viscosity on the core-droplet viscosity. At high shear rates, the relative viscosity increases with increasing core-droplet viscosity. However, the trend is opposite at low shear rates, which results from the high inward flow (Marangoni flow) at low core-droplet viscosity.

An Interactive, Design and Educational Tool for Supersonic External-Compression Inlets

NASA Technical Reports Server (NTRS)

Benson, Thomas J.

1994-01-01

A workstation-based interactive design tool called VU-INLET was developed for the inviscid flow in rectangular, supersonic, external-compression inlets. VU-INLET solves for the flow conditions from free stream, through the supersonic compression ramps, across the terminal normal shock region and the subsonic diffuser to the engine face. It calculates the shock locations, the capture streamtube, and the additive drag of the inlet. The inlet geometry can be modified using a graphical user interface and the new flow conditions recalculated interactively. Free stream conditions and engine airflow can also be interactively varied and off-design performance evaluated. Flow results from VU-INLET can be saved to a file for a permanent record, and a series of help screens make the simulator easy to learn and use. This paper will detail the underlying assumptions of the models and the numerical methods used in the simulator.

The Design of Pumpjets for Hydrodynamic Propulsion

NASA Technical Reports Server (NTRS)

Bruce, E. P.; Gearhart, W. S.; Ross, J. R.; Treaster, A. L.

1974-01-01

A procedure for use in the design of a wake adapted pumpjet mounted on the aft end of a body of revolution is presented. To this end, a pumpjet is designed for the Akron airship. The propulsor mass flow is selected to minimize kinetic energy losses through the duct and in the discharge jet. The shaft speed and disk size are selected to satisfy specified limits of cavitation performance and to provide acceptable blade loading. The streamtubes which pass through a propulsor mounted on a tapered afterbody follow essentially conical surfaces. A method is provided for defining these surfaces as a function of shroud geometry, rotor head distribution, and the energy distribution of the ingested mass flow. The three-dimensional effects to which the conical flow subjects the cylindrical blade design sections are described and a technique is presented which permits incorporation of these effects in the blade design procedure.

A simple tandem disk model for a cross-wind machine

NASA Astrophysics Data System (ADS)

Healey, J. V.

The relative power coefficients, area expansion ratio, and crosswind forces for a crosswind tubine, e.g., the Darrieus, were examined with a tandem-disk, single-streamtube model. The upwind disk is assumed to be rectangular and the downwind disk is modeled as filling the wake of the upwind disk. Velocity and force triangles are devised for the factors operating at each blade. Attention was given to the NACA 0012 and 0018, and Go 735 and 420 airfoils as blades, with Reynolds number just under 500,000. The 0018 was found to be the best airfoil, followed by the 0012, the 735, and, very far behind in terms of the power coefficient, the 420. The forces on the two disks were calculated to be equal at low tip speed ratios with symmetrical airfoil, while the Go cambered profiles yielded negative values upwind in the same conditions.

A Thermodynamically General Theory for Convective Circulations and Vortices

NASA Astrophysics Data System (ADS)

Renno, N. O.

2007-12-01

Convective circulations and vortices are common features of atmospheres that absorb low-entropy-energy at higher temperatures than they reject high-entropy-energy to space. These circulations range from small to planetary-scale and play an important role in the vertical transport of heat, momentum, and tracer species. Thus, the development of theoretical models for convective phenomena is important to our understanding of many basic features of planetary atmospheres. A thermodynamically general theory for convective circulations and vortices is proposed. The theory includes irreversible processes and quantifies the pressure drop between the environment and any point in a convective updraft. The article's main result is that the proposed theory provides an expression for the pressure drop along streamlines or streamtubes that is a generalization of Bernoulli's equation to convective circulations. We speculate that the proposed theory not only explains the intensity, but also shed light on other basic features of convective circulations and vortices.

Analytical study of laser-supported combustion waves in hydrogen

NASA Technical Reports Server (NTRS)

Kemp, N. H.; Root, R. G.

1978-01-01

Laser supported combustion (LSC) waves are an important ingredient in the fluid mechanics of CW laser propulsion using a hydrogen propellant and 10.6 micron lasers. Therefore, a computer model has been constructed to solve the one-dimensional energy equation with constant pressure and area. Physical processes considered include convection, conduction, absorption of laser energy, radiation energy loss, and accurate properties of equilibrium hydrogen. Calculations for 1, 3, 10 and 30 atm were made for intensities of 10 to the 4th to 10 to the 6th W/sq cm, which gave temperature profiles, wave speed, etc. To pursue the propulsion application, a second computer model was developed to describe the acceleration of the gas emerging from the LSC wave into a variable-pressure, converging streamtube, still including all the above-mentioned physical processes. The results show very high temperatures in LSC waves which absorb all the laser energy, and high radiative losses.

Double and Multiple Star Measurements at the Southern Sky with a 50cm-Cassegrain and a Fast CCD Camera in 2008

NASA Astrophysics Data System (ADS)

Anton, Rainer

2011-04-01

Using a 50cm Cassegrain in Namibia, recordings of double and multiple stars were made with a fast CCD camera and a notebook computer. From superpositions of "lucky images", measurements of 149 systems were obtained and compared with literature data. B/W and color images of some remarkable systems are also presented.

Double and Multiple Star Measurements in the Northern Sky with a 10" Newtonian and a Fast CCD Camera in 2006 through 2009

NASA Astrophysics Data System (ADS)

Anton, Rainer

2010-07-01

Using a 10" Newtonian and a fast CCD camera, recordings of double and multiple stars were made at high frame rates with a notebook computer. From superpositions of "lucky images", measurements of 139 systems were obtained and compared with literature data. B/w and color images of some noteworthy systems are also presented.

The Doubling Moment: Resurrecting Edgar Allan Poe

ERIC Educational Resources Information Center

Minnick, J. Bradley; Mergil, Fernando

2008-01-01

This article expands upon Jeffrey Wilhelm's and Brian Edmiston's (1998) concept of a doubling of viewpoints by encouraging middle level students to use dramatization to take on multiple perspectives, to pose interpretive questions, and to enhance critical inquiry from inside and outside of texts. The doubling moment is both the activation of…

Identification and Multiplicity of Double Vowels in Cochlear Implant Users

ERIC Educational Resources Information Center

Kwon, Bomjun J.; Perry, Trevor T.

2014-01-01

Purpose: The present study examined cochlear implant (CI) users' perception of vowels presented concurrently (i.e., "double vowels") to further our understanding of auditory grouping in electric hearing. Method: Identification of double vowels and single vowels was measured with 10 CI subjects. Fundamental frequencies (F0s) of…

Equivalent D = 3 supergravity amplitudes from double copies of three-algebra and two-algebra gauge theories.

PubMed

Huang, Yu-tin; Johansson, Henrik

2013-04-26

We show that three-dimensional supergravity amplitudes can be obtained as double copies of either three-algebra super-Chern-Simons matter theory or two-algebra super-Yang-Mills theory when either theory is organized to display the color-kinematics duality. We prove that only helicity-conserving four-dimensional gravity amplitudes have nonvanishing descendants when reduced to three dimensions, implying the vanishing of odd-multiplicity S-matrix elements, in agreement with Chern-Simons matter theory. We explicitly verify the double-copy correspondence at four and six points for N = 12,10,8 supergravity theories and discuss its validity for all multiplicity.

Modeling radiative transfer with the doubling and adding approach in a climate GCM setting

NASA Astrophysics Data System (ADS)

Lacis, A. A.

2017-12-01

The nonlinear dependence of multiply scattered radiation on particle size, optical depth, and solar zenith angle, makes accurate treatment of multiple scattering in the climate GCM setting problematic, due primarily to computational cost issues. In regard to the accurate methods of calculating multiple scattering that are available, their computational cost is far too prohibitive for climate GCM applications. Utilization of two-stream-type radiative transfer approximations may be computationally fast enough, but at the cost of reduced accuracy. We describe here a parameterization of the doubling/adding method that is being used in the GISS climate GCM, which is an adaptation of the doubling/adding formalism configured to operate with a look-up table utilizing a single gauss quadrature point with an extra-angle formulation. It is designed to closely reproduce the accuracy of full-angle doubling and adding for the multiple scattering effects of clouds and aerosols in a realistic atmosphere as a function of particle size, optical depth, and solar zenith angle. With an additional inverse look-up table, this single-gauss-point doubling/adding approach can be adapted to model fractional cloud cover for any GCM grid-box in the independent pixel approximation as a function of the fractional cloud particle sizes, optical depths, and solar zenith angle dependence.

Interferometric Methods of Measuring Refractive Indices and Double-Refraction of Fibres.

ERIC Educational Resources Information Center

Hamza, A. A.; El-Kader, H. I. Abd

1986-01-01

Presents two methods used to measure the refractive indices and double-refraction of fibers. Experiments are described, with one involving the use of Pluta microscope in the double-beam interference technique, the other employing the multiple-beam technique. Immersion liquids are discussed that can be used in the experiments. (TW)

Double emulsions from a capillary array injection microfluidic device.

PubMed

Shang, Luoran; Cheng, Yao; Wang, Jie; Ding, Haibo; Rong, Fei; Zhao, Yuanjin; Gu, Zhongze

2014-09-21

A facile microfluidic device was developed by inserting an annular capillary array into a collection channel for single-step emulsification of double emulsions. By inserting multiple inner-phase solutions into the capillary array, multicomponent double emulsions or microcapsules with inner droplets of different content could also be obtained from the device.

STT Doubles with Large δM - Part VI: Cygnus Multiples

NASA Astrophysics Data System (ADS)

Knapp, Wilfried; Nanson, John

2016-10-01

The results of visual double star observing sessions suggested a pattern for STT doubles with large delta_M of being harder to resolve than would be expected based on the WDS catalog data. It was felt this might be a problem with expectations on one hand, and on the other might be an indication of a need for new precise measurements, so we decided to take a closer look at a selected sample of STT doubles and do some research. Of these objects we found three rather complex multiples in Cygnus of special interest so we decided to write a separate report to have more room to include the non STT components as well. Again like for the other objects covered so far several of the components show parameters quite different from the current WDS data.

Dual-circuit, multiple-effect refrigeration system and method

DOEpatents

DeVault, Robert C.

1995-01-01

A dual circuit absorption refrigeration system comprising a high temperature single-effect refrigeration loop and a lower temperature double-effect refrigeration loop separate from one another and provided with a double-condenser coupling therebetween. The high temperature condenser of the single-effect refrigeration loop is double coupled to both of the generators in the double-effect refrigeration loop to improve internal heat recovery and a heat and mass transfer additive such as 2-ethyl-1-hexanol is used in the lower temperature double-effect refrigeration loop to improve the performance of the absorber in the double-effect refrigeration loop.

Multiple ionization of C 60 in collisions with 2.33 MeV/u O-ions and giant plasmon excitation

NASA Astrophysics Data System (ADS)

Kelkar, A. H.; Kadhane, U.; Misra, D.; Kumar, Ajay; Tribedi, L. C.

2007-03-01

Single and multiple ionization of C60 in collisions with fast (v = 9.7 a.u.) Oq+ ions have been studied. Relative cross sections for production of C 601+ to C 604+ have been measured. The intensity ratios of double-to-single ionization agree very well with a model based on giant dipole plasmon resonance (GDPR). Almost linear increasing trend of the yields of single and double ionizations with projectile charge state is well reproduced by the single and double plasmon excitation mechanisms. The observed charge state independence of triple and quadruple ionization is in sharp contrast to the GDPR model.

[Investigation of RNA viral genome amplification by multiple displacement amplification technique].

PubMed

Pang, Zheng; Li, Jian-Dong; Li, Chuan; Liang, Mi-Fang; Li, De-Xin

2013-06-01

In order to facilitate the detection of newly emerging or rare viral infectious diseases, a negative-strand RNA virus-severe fever with thrombocytopenia syndrome bunyavirus, and a positive-strand RNA virus-dengue virus, were used to investigate RNA viral genome unspecific amplification by multiple displacement amplification technique from clinical samples. Series of 10-fold diluted purified viral RNA were utilized as analog samples with different pathogen loads, after a series of reactions were sequentially processed, single-strand cDNA, double-strand cDNA, double-strand cDNA treated with ligation without or with supplemental RNA were generated, then a Phi29 DNA polymerase depended isothermal amplification was employed, and finally the target gene copies were detected by real time PCR assays to evaluate the amplification efficiencies of various methods. The results showed that multiple displacement amplification effects of single-strand or double-strand cDNA templates were limited, while the fold increases of double-strand cDNA templates treated with ligation could be up to 6 X 10(3), even 2 X 10(5) when supplemental RNA existed, and better results were obtained when viral RNA loads were lower. A RNA viral genome amplification system using multiple displacement amplification technique was established in this study and effective amplification of RNA viral genome with low load was achieved, which could provide a tool to synthesize adequate viral genome for multiplex pathogens detection.

Multiple period-doubling bifurcation route to chaos in periodically pulsed Murali-Lakshmanan-Chua circuit-controlling and synchronization of chaos.

PubMed

Parthasarathy, S; Manikandakumar, K

2007-12-01

We consider a simple nonautonomous dissipative nonlinear electronic circuit consisting of Chua's diode as the only nonlinear element, which exhibit a typical period doubling bifurcation route to chaotic oscillations. In this paper, we show that the effect of additional periodic pulses in this Murali-Lakshmanan-Chua (MLC) circuit results in novel multiple-period-doubling bifurcation behavior, prior to the onset of chaos, by using both numerical and some experimental simulations. In the chaotic regime, this circuit exhibits a rich variety of dynamical behavior including enlarged periodic windows, attractor crises, distinctly modified bifurcation structures, and so on. For certain types of periodic pulses, this circuit also admits transcritical bifurcations preceding the onset of multiple-period-doubling bifurcations. We have characterized our numerical simulation results by using Lyapunov exponents, correlation dimension, and power spectrum, which are found to be in good agreement with the experimental observations. Further controlling and synchronization of chaos in this periodically pulsed MLC circuit have been achieved by using suitable methods. We have also shown that the chaotic attractor becomes more complicated and their corresponding return maps are no longer simple for large n-periodic pulses. The above study also indicates that one can generate any desired n-period-doubling bifurcation behavior by applying n-periodic pulses to a chaotic system.

Differential tumor biology effects of double-initiation in a mouse skin chemical carcinogenesis model comparing wild type versus protein kinase Cepsilon overexpression mice.

PubMed

Li, Yafan; Wheeler, Deric L; Ananthaswamy, Honnavara N; Verma, Ajit K; Oberley, Terry D

2007-12-01

Our previous studies showed that protein kinase Cepsilon (PKCepsilon) verexpression in mouse skin resulted in metastatic squamous cell carcinoma (SCC) elicited by single 7,12-dimethylbenz(a)anthracene (DMBA)-initiation and 12-O-tetradecanoylphorbol-13-acetate (TPA)-promotion in the absence of preceding papilloma formation as is typically observed in wild type mice. The present study demonstrates that double-DMBA initiation modulates tumor incidence, multiplicity, and latency period in both wild type and PKCepsilon overexpression transgenic (PKCepsilon-Tg) mice. After 17 weeks (wks) of tumor promotion, a reduction in papilloma multiplicity was observed in double- versus single-DMBA initiated wild type mice. Papilloma multiplicity was inversely correlated with cell death indices of interfollicular keratinocytes, indicating decreased papilloma formation was caused by increased cell death and suggesting the origin of papillomas is in interfollicular epidermis. Double-initiated PKCepsilon-Tg mice had accelerated carcinoma formation and cancer incidence in comparison to single-initiated PKCepsilon-Tg mice. Morphologic analysis of mouse skin following double initiation and tumor promotion showed a similar if not identical series of events to those previously observed following single initiation and tumor promotion: putative preneoplastic cells were observed arising from hyperplastic hair follicles (HFs) with subsequent cancer cell infiltration into the dermis. Single-initiated PKCepsilon-Tg mice exhibited increased mitosis in epidermal cells of HFs during tumor promotion.

Brilliant Blue G double staining enhances successful internal limiting membrane peeling with minimal adverse effect by low cellular permeability into live cells.

PubMed

Hisatomi, Toshio; Notomi, Shoji; Tachibana, Takashi; Oishi, Seiichiro; Asato, Ryo; Yamashita, Takehiro; Murakami, Yusuke; Ikeda, Yasuhiro; Enaida, Hiroshi; Sakamoto, Taiji; Ishibashi, Tatsuro

2015-02-01

Brilliant Blue G is used as a surgical adjuvant for retinal surgery. Although BBG double or multiple staining was reported, the effectiveness and safety of repeated staining is still elusive. To further examine the effectiveness and safety, we examined BBG in clinical cases in vivo, primary cell culture in vitro, and surgically resected specimen ex vivo. A retrospective interventional case series with in vitro and ex vivo studies were performed. Vitrectomy was performed in 28 cases of epiretinal membrane with BBG single to multiple staining. The surgically resected membranes were stained by BBG with or without cellular fixation. Primary cell cultures were examined with BBG and live/death cell markers, such as Calcein AM and TUNEL. Single staining provided satisfactory staining in seven cases. Double or multiple staining substantially visualized internal limiting membrane (21 cases), especially the edges of remaining internal limiting membrane (11 cases). Adverse retinal staining was not noted and the final visual acuity showed no difference with multiple staining. The live cells barely stained with BBG, while some dead cells were stained. Brilliant Blue G multiple staining substantially enhanced the visualization of internal limiting membrane. The absence of abnormal staining supports the safety of repeated BBG staining.

Decoupling suspension controller based on magnetic flux feedback.

PubMed

Zhang, Wenqing; Li, Jie; Zhang, Kun; Cui, Peng

2013-01-01

The suspension module control system model has been established based on MIMO (multiple input and multiple output) state feedback linearization. We have completed decoupling between double suspension points, and the new decoupling method has been applied to CMS04 magnetic suspension vehicle in national mid-low-speed maglev experiment field of Tangshan city in China. Double suspension system model is very accurate for investigating stability property of maglev control system. When magnetic flux signal is taken back to the suspension control system, the suspension module's antijamming capacity for resisting suspension load variety has been proved. Also, the external force interference has been enhanced. As a result, the robustness and stability properties of double-electromagnet suspension control system have been enhanced.

Decoupling Suspension Controller Based on Magnetic Flux Feedback

PubMed Central

Zhang, Wenqing; Li, Jie; Zhang, Kun; Cui, Peng

2013-01-01

The suspension module control system model has been established based on MIMO (multiple input and multiple output) state feedback linearization. We have completed decoupling between double suspension points, and the new decoupling method has been applied to CMS04 magnetic suspension vehicle in national mid-low-speed maglev experiment field of Tangshan city in China. Double suspension system model is very accurate for investigating stability property of maglev control system. When magnetic flux signal is taken back to the suspension control system, the suspension module's antijamming capacity for resisting suspension load variety has been proved. Also, the external force interference has been enhanced. As a result, the robustness and stability properties of double-electromagnet suspension control system have been enhanced. PMID:23844415

Particle Identification in Nuclear Emulsion by Measuring Multiple Coulomb Scattering

NASA Astrophysics Data System (ADS)

Than Tint, Khin; Nakazawa, Kazuma; Yoshida, Junya; Kyaw Soe, Myint; Mishina, Akihiro; Kinbara, Shinji; Itoh, Hiroki; Endo, Yoko; Kobayashi, Hidetaka; E07 Collaboration

2014-09-01

We are developing particle identification techniques for single charged particles such as Xi, proton, K and π by measuring multiple Coulomb scattering in nuclear emulsion. Nuclear emulsion is the best three dimensional detector for double strangeness (S = -2) nuclear system. We expect to accumulate about 10000 Xi-minus stop events which produce double lambda hypernucleus in J-PARC E07 emulsion counter hybrid experiment. The purpose of this particle identification (PID) in nuclear emulsion is to purify Xi-minus stop events which gives information about production probability of double hypernucleus and branching ratio of decay mode. Amount of scattering parameterized as angular distribution and second difference is inversely proportional to the momentum of particle. We produced several thousands of various charged particle tracks in nuclear emulsion stack via Geant4 simulation. In this talk, PID with some measuring methods for multiple scattering will be discussed by comparing with simulation data and real Xi-minus stop events in KEK-E373 experiment.

CCD Measurements of Double and Multiple Stars at NAO Rozhen and ASV in 2015

NASA Astrophysics Data System (ADS)

Cvetković, Z.; Pavlović, R.; Boeva, S.

2017-04-01

Results of CCD observations of 154 double or multiple stars, made with the 2 m telescope of the Bulgarian National Astronomical Observatory at Rozhen over five nights in 2015, are presented. This is the ninth series of measurements of CCD frames obtained at Rozhen. We also present results of CCD observations of 323 double or multiple stars made with the 0.6 m telescope of the Serbian Astronomical Station on the mountain of Vidojevica over 23 nights in 2015. This is the fourth series of measurements of CCD frames obtained at this station. This paper contains the results for the position angle and angular separation for 801 pairs and residuals for 127 pairs with published orbital elements or linear solutions. The angular separations are in the range from 1.″52 to 201.″56, with a median angular separation of 8.″26. We also present eight pairs that are measured for the first time and linear elements for five pairs.

A Modified Double Multiple Nonlinear Regression Constitutive Equation for Modeling and Prediction of High Temperature Flow Behavior of BFe10-1-2 Alloy

NASA Astrophysics Data System (ADS)

Cai, Jun; Wang, Kuaishe; Shi, Jiamin; Wang, Wen; Liu, Yingying

2018-01-01

Constitutive analysis for hot working of BFe10-1-2 alloy was carried out by using experimental stress-strain data from isothermal hot compression tests, in a wide range of temperature of 1,023 1,273 K, and strain rate range of 0.001 10 s-1. A constitutive equation based on modified double multiple nonlinear regression was proposed considering the independent effects of strain, strain rate, temperature and their interrelation. The predicted flow stress data calculated from the developed equation was compared with the experimental data. Correlation coefficient (R), average absolute relative error (AARE) and relative errors were introduced to verify the validity of the developed constitutive equation. Subsequently, a comparative study was made on the capability of strain-compensated Arrhenius-type constitutive model. The results showed that the developed constitutive equation based on modified double multiple nonlinear regression could predict flow stress of BFe10-1-2 alloy with good correlation and generalization.

Analytical method for predicting the pressure distribution about a nacelle at transonic speeds

NASA Technical Reports Server (NTRS)

Keith, J. S.; Ferguson, D. R.; Merkle, C. L.; Heck, P. H.; Lahti, D. J.

1973-01-01

The formulation and development of a computer analysis for the calculation of streamlines and pressure distributions around two-dimensional (planar and axisymmetric) isolated nacelles at transonic speeds are described. The computerized flow field analysis is designed to predict the transonic flow around long and short high-bypass-ratio fan duct nacelles with inlet flows and with exhaust flows having appropriate aerothermodynamic properties. The flow field boundaries are located as far upstream and downstream as necessary to obtain minimum disturbances at the boundary. The far-field lateral flow field boundary is analytically defined to exactly represent free-flight conditions or solid wind tunnel wall effects. The inviscid solution technique is based on a Streamtube Curvature Analysis. The computer program utilizes an automatic grid refinement procedure and solves the flow field equations with a matrix relaxation technique. The boundary layer displacement effects and the onset of turbulent separation are included, based on the compressible turbulent boundary layer solution method of Stratford and Beavers and on the turbulent separation prediction method of Stratford.

Large-eddy simulation of propeller wake at design operating conditions

NASA Astrophysics Data System (ADS)

Kumar, Praveen; Mahesh, Krishnan

2016-11-01

Understanding the propeller wake is crucial for efficient design and optimized performance. The dynamics of the propeller wake are also central to physical phenomena such as cavitation and acoustics. Large-eddy simulation is used to study the evolution of the wake of a five-bladed marine propeller from near to far field at design operating condition. The computed mean loads and phase-averaged flow field show good agreement with experiments. The propeller wake consisting of tip and hub vortices undergoes streamtube contraction, which is followed by the onset of instabilities as evident from the oscillations of the tip vortices. Simulation results reveal a mutual induction mechanism of instability where instead of the tip vortices interacting among themselves, they interact with the smaller vortices generated by the roll-up of the blade trailing edge wake in the near wake. Phase-averaged and ensemble-averaged flow fields are analyzed to explain the flow physics. This work is supported by ONR.

Classic Bernoulli’s principle derivation and its working hypotheses

NASA Astrophysics Data System (ADS)

Marciotto, Edson R.

2016-07-01

The Bernoulli’s principle states that the quantity p+ρ gz+ρ {{v}2}/2 must be conserved in a streamtube if some conditions are matched, namely: steady and irrotational flow of an inviscid and incompressible fluid. In most physics textbooks this result is demonstrated invoking the energy conservation of a fluid material volume at two different positions of a pipe whose cross-section and height vary along its way. Although the final result is correct the right justifications presented in textbooks are usually unclear or absent. The main problem rests on the work done by pressure, which are not found to be fully justified via free-body diagrams as depicted in many general physics textbooks, not to mention plenty of videos on YouTube that incur in similar omissions. In this article I will discuss this issue and how it is solved without resorting to alternative demonstrations. In addition, I discuss the needs of the assumptions to get the Bernoulli’s principle in a way viable to introductory physics courses.

Multiplication Fact Fluency Using Doubles

ERIC Educational Resources Information Center

Flowers, Judith M.; Rubenstein, Rheta N.

2010-01-01

Not knowing multiplication facts creates a gap in a student's mathematics development and undermines confidence and disposition toward further mathematical learning. Learning multiplication facts is a first step in proportional reasoning, "the capstone of elementary arithmetic and the gateway to higher mathematics" (NRC 2001, p. 242). Proportional…

Landslide: Systematic Dynamic Race Detection in Kernel Space

DTIC Science & Technology

2012-05-01

schedule_in_flight← true; CAUSE_TIMER_INTERRUPT(); end if end function Thread Scheduling Finally, the Landslide scheduler is responsible for managing ...child process vanish() simultaneously. • double_wait: Tests interactions of multiple waiters on a single child. • double_thread_fork: Tests for...conditions using Landslide. We describe them here. • Too many waiters allowed. Using the double_wait test case, Group 1 found a bug in which more threads

Double Star Measurements at the Southern Sky with 50 cm Reflectors and Fast CCD Cameras in 2012

NASA Astrophysics Data System (ADS)

Anton, Rainer

2014-07-01

A Cassegrain and a Ritchey-Chrétien reflector, both with 50 cm aperture, were used in Namibia for recordings of double stars with fast CCD cameras and a notebook computer. From superposition of "lucky images", measurements of 39 double and multiple systems were obtained and compared with literature data. Occasional deviations are discussed. Images of some remarkable systems are also presented.

Isolated double adrenocorticotropic hormone-secreting pituitary adenomas: A case report and review of the literature

PubMed Central

PU, JIUJUN; WANG, ZHIMING; ZHOU, HUI; ZHONG, AILING; JIN, KAI; RUAN, LUNLIANG; YANG, GANG

2016-01-01

Only a few cases of double or multiple pituitary adenomas have previously been reported in the literature; however, isolated double adrenocorticotropic hormone (ACTH)-secreting pituitary adenomas are even more rare. The present study reports a rare case of a 50-year-old female patient who presented with typical clinical features of Cushing's disease and was diagnosed with isolated double ACTH-secreting pituitary adenomas. Endocrinological examination revealed an ACTH-producing pituitary adenoma, and preoperative magnetic resonance imaging (MRI) demonstrated a microadenoma with a lower intensity on the right side of the pituitary gland. The patient underwent endoscopic endonasal transsphenoidal surgery, which revealed another pituitary tumor in the left side of the pituitary gland. The two, clearly separated, pituitary adenomas identified in the same gland were completely resected. Immunohistochemistry and pathology revealed that the clearly separated double pituitary adenomas were positive for ACTH, thyroid-stimulating, growth and prolactin hormones. Postoperatively, the levels of ACTH and cortisol hormone decreased rapidly. The case reported in the present study is considerably rare, due to the presence of a second pituitary adenoma in the same gland, which was not detected by preoperative MRI scan, but was noticed during surgery. Intraoperative evaluation may be important in the identification of double or multiple pituitary adenomas. PMID:27347184

Conceptual model for transport processes in the Culebra Dolomite Member, Rustler Formation

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

Holt, R.M.

1997-08-01

The Culebra Dolomite Member of the Rustler Formation represents a possible pathway for contaminants from the Waste Isolation Pilot Plant underground repository to the accessible environment. The geologic character of the Culebra is consistent with a double-porosity, multiple-rate model for transport in which the medium is conceptualized as consisting of advective porosity, where solutes are carried by the groundwater flow, and fracture-bounded zones of diffusive porosity, where solutes move through slow advection or diffusion. As the advective travel length or travel time increases, the nature of transport within a double-porosity medium changes. This behavior is important for chemical sorption, becausemore » the specific surface area per unit mass of the diffusive porosity is much greater than in the advective porosity. Culebra transport experiments conducted at two different length scales show behavior consistent with a multiple-rate, double-porosity conceptual model for Culebra transport. Tracer tests conducted on intact core samples from the Culebra show no evidence of significant diffusion, suggesting that at the core scale the Culebra can be modeled as a single-porosity medium where only the advective porosity participates in transport. Field tracer tests conducted in the Culebra show strong double-porosity behavior that is best explained using a multiple-rate model.« less

Distributed finite-time containment control for double-integrator multiagent systems.

PubMed

Wang, Xiangyu; Li, Shihua; Shi, Peng

2014-09-01

In this paper, the distributed finite-time containment control problem for double-integrator multiagent systems with multiple leaders and external disturbances is discussed. In the presence of multiple dynamic leaders, by utilizing the homogeneous control technique, a distributed finite-time observer is developed for the followers to estimate the weighted average of the leaders' velocities at first. Then, based on the estimates and the generalized adding a power integrator approach, distributed finite-time containment control algorithms are designed to guarantee that the states of the followers converge to the dynamic convex hull spanned by those of the leaders in finite time. Moreover, as a special case of multiple dynamic leaders with zero velocities, the proposed containment control algorithms also work for the case of multiple stationary leaders without using the distributed observer. Simulations demonstrate the effectiveness of the proposed control algorithms.

Double trisomy 48,XXX,+18 with multiple dysmorphic features.

PubMed

Jiang, Zi-Yan; Wu, Xiao-Hui; Zou, Chao-Chun

2015-02-01

Chromosomal abnormality is a common cause of congenital anomalies, psychiatric disorders, and mental retardation. However, the double trisomy 48,XXX,+18 is a rare chromosome abnormality. Case report and literature review. A 7-hour-old girl presented to our unit because of poor response after birth. She presented with multiple dysmorphic features, including small for gestational age infant, flat nasal bridge, widely-spaced eyes, the left thumb deformities, flat facial profile, raised sternum, ventricular septal defect, the third lateral brain ventricle enlargement, and small liver. This case expands the spectrum of malformations reported in association with the double trisomy 48,XXX,+18. The literature on 16 fetuses or infants with the 48,XXX,+18 were also reviewed. These data suggested that in patients with clinical features similar to trisomy 18, especially with anomalies of the ears and/or reproductive malformations, double trisomy (48,XXX,+18) should be considered and karyotyping should be performed although it is a rare disease.

Can Multiple Cropping Help to Avoid the Impacts of Heat Extremes? The Case of Winter Wheat/Soybean Double Cropping in the United States

NASA Astrophysics Data System (ADS)

Seifert, C.; Lobell, D. B.

2014-12-01

In adapting U.S. agriculture to the climate of the 21st century, multiple cropping presents a unique opportunity to help offset projected negative trends in agricultural production while moving critical crop yield formation periods outside of the hottest months of the year. Critical constraints on this practice include moisture availability, and, more importantly, growing season length. We review evidence that this last constraint has decreased in the previous quarter century, allowing for more winter wheat/soybean double cropping in previously phenologically constrained areas. We also carry this pattern forward to 2100, showing a 126% to 211% increase in the area phenologically suitable for double cropping under the RCP45 and RCP85 scenarios respectively. These results suggest that climate change will relieve phenological constraints on wheat-soy double cropping systems over much of the United States, changing production patterns and crop rotations as areas become suitable for the practice.

Multiple quay cranes scheduling for double cycling in container terminals

PubMed Central

Chu, Yanling; Zhang, Xiaoju; Yang, Zhongzhen

2017-01-01

Double cycling is an efficient tool to increase the efficiency of quay crane (QC) in container terminals. In this paper, an optimization model for double cycling is developed to optimize the operation sequence of multiple QCs. The objective is to minimize the makespan of the ship handling operation considering the ship balance constraint. To solve the model, an algorithm based on Lagrangian relaxation is designed. Finally, we compare the efficiency of the Lagrangian relaxation based heuristic with the branch-and-bound method and a genetic algorithm using instances of different sizes. The results of numerical experiments indicate that the proposed model can effectively reduce the unloading and loading times of QCs. The effects of the ship balance constraint are more notable when the number of QCs is high. PMID:28692699

Multiple quay cranes scheduling for double cycling in container terminals.

PubMed

Chu, Yanling; Zhang, Xiaoju; Yang, Zhongzhen

2017-01-01

Double cycling is an efficient tool to increase the efficiency of quay crane (QC) in container terminals. In this paper, an optimization model for double cycling is developed to optimize the operation sequence of multiple QCs. The objective is to minimize the makespan of the ship handling operation considering the ship balance constraint. To solve the model, an algorithm based on Lagrangian relaxation is designed. Finally, we compare the efficiency of the Lagrangian relaxation based heuristic with the branch-and-bound method and a genetic algorithm using instances of different sizes. The results of numerical experiments indicate that the proposed model can effectively reduce the unloading and loading times of QCs. The effects of the ship balance constraint are more notable when the number of QCs is high.

Double Cantilever Beam Fracture Toughness Testing of Several Composite Materials

NASA Technical Reports Server (NTRS)

Kessler, Jeff A.; Adams, Donald F.

1992-01-01

Double-cantilever beam fracture toughness tests were performed by the Composite Materials Research Group on several different unidirectional composite materials provided by NASA Langley Research Center. The composite materials consisted of Hercules IM-7 carbon fiber and various matrix resin formulations. Multiple formulations of four different families of matrix resins were tested: LaRC - ITPI, LaRC - IA, RPT46T, and RP67/RP55. Report presents the materials tested and pertinent details supplied by NASA. For each material, three replicate specimens were tested. Multiple crack extensions were performed on each replicate.

High frequency of telomeric association in a family with multiple congenital neoplasia.

PubMed

Dhaliwal, M K; Satya-Prakash, K L; Davis, P C; Pathak, S

1994-01-01

Chromosomal analysis of the peripheral blood cultures of a married couple whose second pregnancy gave birth to twin daughters with multiple congenital malignancies revealed normal karyotypes of 46,XX and 46,XY, respectively. However, in the father's blood, 23.3% of metaphases showed telomere-telomere associations involving single-single and double-double chromatids. Such associations were not observed in the metaphases of the mother. We speculate from these observations that the father's genotype may somehow be responsible for the congenital malignancies in their twin daughters.

Bent Bonds and Multiple Bonds.

ERIC Educational Resources Information Center

Robinson, Edward A.; Gillespie, Ronald J.

1980-01-01

Considers carbon-carbon multiple bonds in terms of Pauling's bent bond model, which allows direct calculation of double and triple bonds from the length of a CC single bond. Lengths of these multiple bonds are estimated from direct measurements on "bent-bond" models constructed of plastic tubing and standard kits. (CS)

26 CFR 1.381(c)(5)-1 - Inventories.

Code of Federal Regulations, 2011 CFR

2011-04-01

... the dollar-value method, use the double-extension method, pool under the natural business unit method... double-extension method, pool under the natural business unit method, and value annual inventory... natural business unit method while P corporation pools under the multiple pool method. In addition, O...

26 CFR 1.381(c)(5)-1 - Inventories.

Code of Federal Regulations, 2010 CFR

2010-04-01

... the dollar-value method, use the double-extension method, pool under the natural business unit method... double-extension method, pool under the natural business unit method, and value annual inventory... natural business unit method while P corporation pools under the multiple pool method. In addition, O...

Double Star Measurements at the Southern Sky with a 50 cm Reflector and a Fast CCD Camera in 2014

NASA Astrophysics Data System (ADS)

Anton, Rainer

2015-04-01

A Ritchey-Chrétien reflector with 50 cm aperture was used in Namibia for recordings of double stars with a fast CCD camera and a notebook computer. From superposition of "lucky images", measurements of 91 pairings in 79 double and multiple systems were obtained and compared with literature data. Occasional deviations are discussed. Some images of noteworthy systems are also presented.

Double-observer line transect surveys with Markov-modulated Poisson process models for animal availability.

PubMed

Borchers, D L; Langrock, R

2015-12-01

We develop maximum likelihood methods for line transect surveys in which animals go undetected at distance zero, either because they are stochastically unavailable while within view or because they are missed when they are available. These incorporate a Markov-modulated Poisson process model for animal availability, allowing more clustered availability events than is possible with Poisson availability models. They include a mark-recapture component arising from the independent-observer survey, leading to more accurate estimation of detection probability given availability. We develop models for situations in which (a) multiple detections of the same individual are possible and (b) some or all of the availability process parameters are estimated from the line transect survey itself, rather than from independent data. We investigate estimator performance by simulation, and compare the multiple-detection estimators with estimators that use only initial detections of individuals, and with a single-observer estimator. Simultaneous estimation of detection function parameters and availability model parameters is shown to be feasible from the line transect survey alone with multiple detections and double-observer data but not with single-observer data. Recording multiple detections of individuals improves estimator precision substantially when estimating the availability model parameters from survey data, and we recommend that these data be gathered. We apply the methods to estimate detection probability from a double-observer survey of North Atlantic minke whales, and find that double-observer data greatly improve estimator precision here too. © 2015 The Authors Biometrics published by Wiley Periodicals, Inc. on behalf of International Biometric Society.

Characterization of normal feline renal vascular anatomy with dual-phase CT angiography.

PubMed

Cáceres, Ana V; Zwingenberger, Allison L; Aronson, Lillian R; Mai, Wilfried

2008-01-01

Helical computed tomography angiography was used to evaluate the renal vascular anatomy of potential feline renal donors. One hundred and fourteen computed tomography angiograms were reviewed. The vessels were characterized as single without bifurcation, single with bifurcation, double, or triple. Multiplicity was most commonly seen for the right renal vein (45/114 vs. 3/114 multiple left renal veins, 0/114 multiple right renal arteries, and 8/114 multiple left renal arteries). The right kidney was 13.3 times more likely than the left to have multiple renal veins. Additional vascular variants included double caudal vena cava and an accessory renal artery. For the left kidney, surgery and computed tomography angiography findings were in agreement in 92% of 74 cats. For the right kidney, surgery and computed tomography angiography findings were in agreement in 6/6 cats. Our findings of renal vascular anatomy variations in cats were similar to previous reports in humans. Identifying and recognizing the pattern of distribution of these vessels is important when performing renal transplantation.

Children's multiplicative transformations of discrete and continuous quantities.

PubMed

Barth, Hilary; Baron, Andrew; Spelke, Elizabeth; Carey, Susan

2009-08-01

Recent studies have documented an evolutionarily primitive, early emerging cognitive system for the mental representation of numerical quantity (the analog magnitude system). Studies with nonhuman primates, human infants, and preschoolers have shown this system to support computations of numerical ordering, addition, and subtraction involving whole number concepts prior to arithmetic training. Here we report evidence that this system supports children's predictions about the outcomes of halving and perhaps also doubling transformations. A total of 138 kindergartners and first graders were asked to reason about the quantity resulting from the doubling or halving of an initial numerosity (of a set of dots) or an initial length (of a bar). Controls for dot size, total dot area, and dot density ensured that children were responding to the number of dots in the arrays. Prior to formal instruction in symbolic multiplication, division, or rational number, halving (and perhaps doubling) computations appear to be deployed over discrete and possibly continuous quantities. The ability to apply simple multiplicative transformations to analog magnitude representations of quantity may form a part of the toolkit that children use to construct later concepts of rational number.

Fiber sensor network with multipoint sensing using double-pass hybrid LPFG-FBG sensor configuration

NASA Astrophysics Data System (ADS)

Yong, Yun-Thung; Lee, Sheng-Chyan; Rahman, Faidz Abd

2017-03-01

This is a study on double-pass intensity-based hybrid Long Period Fiber Grating (LPFG)and Fiber Bragg Grating (FBG) sensor configuration where a fiber sensor network was constructed with multiple sensing capability. The sensing principle is based on interrogation of intensity changes of the reflected signal from an FBG caused by the LPFG spectral response to the surrounding perturbations. The sensor network developed was tested in monitoring diesel adulteration of up to a distance of 8 km. Kerosene concentration from 0% to 50% was added as adulterant into diesel. The sensitivity of the double-pass hybrid LPFG-FBG sensor over multiple points was>0.21 dB/% (for adulteration range of 0-30%) and >0.45 dB/% from 30% to 50% adulteration. It is found that the sensitivity can drop up to 35% when the fiber length increased from 0 km to 8 km (for the case of adulteration of 0-30%). With the multiple sensing capabilities, normalized FBG's reflected power can be demodulated at the same time for comparison of sensitivity performance across various fiber sensors.

Construction, expression, purification and biotin labeling of a single recombinant multi-epitope antigen for double-antigen sandwich ELISA to detect hepatitis C virus antibody.

PubMed

He, Jing; Xiu, Bingshui; Wang, Guohua; Chen, Kun; Feng, Xiaoyan; Song, Xiaoguo; Zhu, Cuixia; Yang, Xiqin; Bai, Guanzhong; Ling, Shigan; Zhang, Heqiu

2011-08-01

Based on B cell epitope predictions, a recombinant antigen with multiple epitopes from four Hepatitis C Virus fragments (C, NS3, NS4 and NS5) were engineered. The recombinant gene was then highly expressed in E. coli. The non-modified and C-terminal-modified recombinant proteins were used for coating and biotin labeling, respectively, to establish the double-antigen sandwich ELISA. Ten positive reference samples confirmed by the CHIRON RIBA HCV 3.0 SIA kit were detected positive, Forty one plasma samples were positive among samples from 441 volunteers, which indicated that the recombinant antigen could readily react well with plasma HCV antibody. As critical reagents of double-antigen sandwich ELISA, the recombinant multi-epitope antigen and the C-terminal-modified and biotin-conjugated antigen show good antigenicity. In this study, we provide a simple approach to produce multiple epitopes within one recombinant protein in order to avoid the costly expression of less-effective pools of multiple proteins, which is the conventional strategy of diagnostic antigen production for HCV antibody detection.

Numerical simulations of short-mixing-time double-wave-vector diffusion-weighting experiments with multiple concatenations on whole-body MR systems

NASA Astrophysics Data System (ADS)

Finsterbusch, Jürgen

2010-12-01

Double- or two-wave-vector diffusion-weighting experiments with short mixing times in which two diffusion-weighting periods are applied in direct succession, are a promising tool to estimate cell sizes in the living tissue. However, the underlying effect, a signal difference between parallel and antiparallel wave vector orientations, is considerably reduced for the long gradient pulses required on whole-body MR systems. Recently, it has been shown that multiple concatenations of the two wave vectors in a single acquisition can double the modulation amplitude if short gradient pulses are used. In this study, numerical simulations of such experiments were performed with parameters achievable with whole-body MR systems. It is shown that the theoretical model yields a good approximation of the signal behavior if an additional term describing free diffusion is included. More importantly, it is demonstrated that the shorter gradient pulses sufficient to achieve the desired diffusion weighting for multiple concatenations, increase the signal modulation considerably, e.g. by a factor of about five for five concatenations. Even at identical echo times, achieved by a shortened diffusion time, a moderate number of concatenations significantly improves the signal modulation. Thus, experiments on whole-body MR systems may benefit from multiple concatenations.

Running Multiple Sub-Jobs with One Job Script on the Peregrine System |

Science.gov Websites

=00:10:00 # WALLTIME limit #PBS -l nodes=1:ppn=24 #PBS -q short #PBS -N wait_test #PBS -o std.out #PBS ;stdio.h> main() { double x,h,sum = 0; int i,N; scanf("%d",&N); h=1.0/(double) N; for (i=0 ; i<N; i++) { x=h*((double) i + 0.5); sum += 4.0*h/(1.0+x*x); } printf("\

A Bowtie Antenna Coupled Tunable Photon-Assisted Tunneling Double Quantum Well (DQW) THz Detector

DTIC Science & Technology

2002-01-01

Proc. Vol. 692 © 2002 Materials Research Society H4.2 A Bowtie Antenna Coupled Tunable Photon-Assisted Tunneling Double Quantum Well (DQW) THz Detector ...on photon-assisted tunneling (PAT) between the two electron layers in a double quantum well (DQW) heterostructure, will be explained. The detector is...the frequency and strength of that radiation. The THz detector discussed in this paper makes use of photon- assisted tunnelling (PAT) between multiple

Visual performance on detection tasks with double-targets of the same and different difficulty.

PubMed

Chan, Alan H S; Courtney, Alan J; Ma, C W

2002-10-20

This paper reports a study of measurement of horizontal visual sensitivity limits for 16 subjects in single-target and double-targets detection tasks. Two phases of tests were conducted in the double-targets task; targets of the same difficulty were tested in phase one while targets of different difficulty were tested in phase two. The range of sensitivity for the double-targets test was found to be smaller than that for single-target in both the same and different target difficulty cases. The presence of another target was found to affect performance to a marked degree. Interference effect of the difficult target on detection of the easy one was greater than that of the easy one on the detection of the difficult one. Performance decrement was noted when correct percentage detection was plotted against eccentricity of target in both the single-target and double-targets tests. Nevertheless, the non-significant correlation found between the performance for the two tasks demonstrated that it was impossible to predict quantitatively ability for detection of double targets from the data for single targets. This indicated probable problems in generalizing data for single target visual lobes to those for multiple targets. Also lobe area values obtained from measurements using a single-target task cannot be applied in a mathematical model for situations with multiple occurrences of targets.

Initiation of Detonation in Multiple Shock-Compressed Liquid Explosives

NASA Astrophysics Data System (ADS)

Yoshinaka, A. C.; Zhang, F.; Petel, O. E.; Higgins, A. J.

2006-07-01

Initiation and resulting propagation of detonation via multiple shock reverberations between two high impedance plates has been investigated in amine-sensitized nitromethane. Experiments were designed so that the first reflected shock strength was below the critical value for initiation found previously. Luminosity combined with a distinct pressure hump indicated onset of reaction and successful initiation after double or triple shock reflection off the bottom plate. Final temperature estimates for double or triple shock reflection immediately before initiation lie between 700-720 K, consistent with those found previously for both incident and singly reflected shock initiation.

Nonlocal Poisson-Fermi double-layer models: Effects of nonuniform ion sizes on double-layer structure

NASA Astrophysics Data System (ADS)

Xie, Dexuan; Jiang, Yi

2018-05-01

This paper reports a nonuniform ionic size nonlocal Poisson-Fermi double-layer model (nuNPF) and a uniform ionic size nonlocal Poisson-Fermi double-layer model (uNPF) for an electrolyte mixture of multiple ionic species, variable voltages on electrodes, and variable induced charges on boundary segments. The finite element solvers of nuNPF and uNPF are developed and applied to typical double-layer tests defined on a rectangular box, a hollow sphere, and a hollow rectangle with a charged post. Numerical results show that nuNPF can significantly improve the quality of the ionic concentrations and electric fields generated from uNPF, implying that the effect of nonuniform ion sizes is a key consideration in modeling the double-layer structure.

[Double mutant alleles in the EXT1 gene not previously reported in a teenager with hereditary multiple exostoses].

PubMed

Cammarata-Scalisi, Francisco; Cozar, Mónica; Grinberg, Daniel; Balcells, Susana; Asteggiano, Carla G; Martínez-Domenech, Gustavo; Bracho, Ana; Sánchez, Yanira; Stock, Frances; Delgado-Luengo, Wilmer; Zara-Chirinos, Carmen; Chacín, José Antonio

2015-04-01

Hereditary forms of multiple exostoses, now called EXT1/EXT2-CDG within Congenital Disorders of Glycosylation, are the most common benign bone tumors in humans and clinical description consists of the formation of several cartilage-capped bone tumors, usually benign and localized in the juxta-epiphyseal region of long bones, although wide body dissemination in severe cases is not uncommon. Onset of the disease is variable ranging from 2-3 years up to 13-15 years with an estimated incidence ranging from 1/18,000 to 1/50,000 cases in European countries. We present a double mutant alleles in the EXT1 gene not previously reported in a teenager and her family with hereditary multiple exostoses.

Low temperature probe for dynamic nuclear polarization and multiple-pulse solid-state NMR.

PubMed

Cho, HyungJoon; Baugh, Jonathan; Ryan, Colm A; Cory, David G; Ramanathan, Chandrasekhar

2007-08-01

Here, we describe the design and performance characteristics of a low temperature probe for dynamic nuclear polarization (DNP) experiments, which is compatible with demanding multiple-pulse experiments. The competing goals of a high-Q microwave cavity to achieve large DNP enhancements and a high efficiency NMR circuit for multiple-pulse control lead to inevitable engineering tradeoffs. We have designed two probes-one with a single-resonance RF circuit and a horn-mirror cavity configuration for the microwaves and a second with a double-resonance RF circuit and a double-horn cavity configuration. The advantage of the design is that the sample is in vacuum, the RF circuits are locally tuned, and the microwave resonator has a large internal volume that is compatible with the use of RF and gradient coils.

Multiplicity Counting

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

Geist, William H.

2015-12-01

This set of slides begins by giving background and a review of neutron counting; three attributes of a verification item are discussed: 240Pu eff mass; α, the ratio of (α,n) neutrons to spontaneous fission neutrons; and leakage multiplication. It then takes up neutron detector systems – theory & concepts (coincidence counting, moderation, die-away time); detector systems – some important details (deadtime, corrections); introduction to multiplicity counting; multiplicity electronics and example distributions; singles, doubles, and triples from measured multiplicity distributions; and the point model: multiplicity mathematics.

Use of Double-Loop Learning to Combat Advanced Persistent Threat: Multiple Case Studies

ERIC Educational Resources Information Center

Lamb, Christopher J.

2013-01-01

The Advanced Persistent Threat (APT) presents an ever present and more growing threat to organizations across the globe. Traditional Information Technology (IT) incident response falls short in effectively addressing this threat. This researcher investigated the use of single-loop and double-loop learning in two organizations with internal…

Easy Demonstration of the Poisson Spot

ERIC Educational Resources Information Center

Gluck, Paul

2010-01-01

Many physics teachers have a set of slides of single, double and multiple slits to show their students the phenomena of interference and diffraction. Thomas Young's historic experiments with double slits were indeed a milestone in proving the wave nature of light. But another experiment, namely the Poisson spot, was also important historically and…

Do Double Minority Students Face Double Jeopardy? Testing Minority Stress Theory

ERIC Educational Resources Information Center

Hayes, Jeffrey A.; Chun-Kennedy, Caitlin; Edens, Astrid; Locke, Benjamin D.

2011-01-01

Data from 2 studies revealed that ethnic and sexual minority clients experienced greater psychological distress on multiple dimensions than did European American or heterosexual clients, respectively, as did ethnic and sexual minority students who were not clients. Among sexual minority students, ethnicity was not an added source of distress.…

Characterization of a double WAP domain-containing protein from the red swamp crayfish Procambarus clarkii

USDA-ARS?s Scientific Manuscript database

Crustaceans express multiple whey acidic protein (WAP) domain containing proteins which are components of host immunity. In the present study, a new double WAP domain containing protein was identified from red swamp crayfish Procambarus clarkii, designated Pc-DWD. The ORF is 387 bp, encoding 128 ami...

Transcatheter Closure of Bilateral Multiple Huge Pulmonary Arteriovenous Malformations with Homemade Double-Umbrella Occluders

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

Zhong Hongshan, E-mail: zhonghongshan@hotmail.com; Xu Ke; Shao Haibo

2008-07-15

A 28-year-old man underwent successful transcatheter occlusion of three huge pulmonary arteriovenous malformations (PAVMs) using homemade double-umbrella occluders and stainless steel coils. Thoracic CT with three-dimensional reconstruction and pulmonary angiography were used for treatment planning and follow-up. The diameters of the feeding vessels were 11 mm, 13 mm, and 14 mm, respectively. This report demonstrates the novel design and utility of the double-umbrella occluder, an alternative tool for treatment of large PAVMs.

A Quasi-Experimental Study Investigating the Effect of Scent on Students' Memory of Multiplication Facts and Math Anxiety

ERIC Educational Resources Information Center

Leap, Evelyn M.

2013-01-01

This quasi-experimental study was conducted with two fifth grade classrooms to investigate the effect of scent on students' acquisition and retention of multiplication facts and math anxiety. Forty participants received daily instruction for nine weeks, using a strategy-rich multiplication program called Factivation. Students in the Double Smencil…

Interface reconstruction with emerging charge ordering in hexagonal manganite

PubMed Central

Xu, Changsong; Han, Myung-Geun; Bao, Shanyong; Nan, Cewen; Bellaiche, Laurent

2018-01-01

Multiferroic materials, which simultaneously have multiple orderings, hold promise for use in the next generation of memory devices. We report a novel self-assembled MnO double layer forming at the interface between a multiferroic YMnO3 film and a c-Al2O3 substrate. The crystal structures and the valence states of this MnO double layer were studied by atomically resolved scanning transmission electron microscopy and spectroscopy, as well as density functional theory (DFT) calculations. A new type of charge ordering has been identified within this MnO layer, which also contributes to a polarization along the [001] direction. DFT calculations further establish the occurrence of multiple couplings between charge and lattice in this novel double layer, in addition to the polarization in nearby YMnO3 single layer. The interface reconstruction reported here creates a new playground for emergent physics, such as giant ferroelectricity and strong magnetoelectric coupling, in manganite systems. PMID:29795782

Effects of the inner droplet of double emulsions on the film drainage during a head-on collision

NASA Astrophysics Data System (ADS)

Wang, Jingtao; Jing, Hefeng; Xu, Genmiao; Wang, Xiaoyong; Duan, Zhenya

2015-07-01

As a critical stage which severely affects the final coalescence of droplets, film drainage in the collision process of two simple droplets has been deeply studied for many years. However, the collision of multiple emulsions which contain other phases (like daughter droplets or particles) has never been studied although multiple emulsions are very important in emulsion industries nowadays. In this paper, the head-on collision of two core-shell double emulsions with equal sizes is investigated through a boundary integral method to disclose the effects of the inner droplet on the film drainage. When capillary number Ca is relatively high, due to the effect of the inner droplet on the inner circulation of mother droplets, the film drainage of double emulsions includes three stages: drainage, drainage halt, and second drainage, instead of two stages for that of simple droplets: drainage and drainage halt.

Generating multi-double-scroll attractors via nonautonomous approach.

PubMed

Hong, Qinghui; Xie, Qingguo; Shen, Yi; Wang, Xiaoping

2016-08-01

It is a common phenomenon that multi-scroll attractors are realized by introducing the various nonlinear functions with multiple breakpoints in double scroll chaotic systems. Differently, we present a nonautonomous approach for generating multi-double-scroll attractors (MDSA) without changing the original nonlinear functions. By using the multi-level-logic pulse excitation technique in double scroll chaotic systems, MDSA can be generated. A Chua's circuit, a Jerk circuit, and a modified Lorenz system are given as designed example and the Matlab simulation results are presented. Furthermore, the corresponding realization circuits are designed. The Pspice results are in agreement with numerical simulation results, which verify the availability and feasibility of this method.

Building of nested components by a double-nozzle droplet deposition process

NASA Astrophysics Data System (ADS)

Li, SuLi; Wei, ZhengYing; Du, Jun; Zhao, Guangxi; Wang, Xin; Lu, BingHeng

2016-07-01

According to the nested components jointed with multiple parts,a double-nozzle droplet deposition process was put forward in this paper, and the experimental system was developed. Through the research on the properties of support materials and the process of double-nozzle droplet deposition, the linkage control of the metal droplet deposition and the support material extrusion was realized, and a nested component with complex construction was fabricated directly. Compared with the traditional forming processes, this double-nozzle deposition process has the advantages of short cycle, low cost and so on. It can provide an approach way to build the nested parts.

Lily Pad Doubling: Proportional Reasoning Development

ERIC Educational Resources Information Center

Robichaux-Davis, Rebecca R.

2017-01-01

Progressing from additive to multiplicative thinking is critical for the development of middle school students' proportional reasoning abilities. Yet, many middle school mathematics teachers lack a thorough understanding of additive versus multiplicative situations. This article describes a sequence of instructional activities used to develop the…

Effect of rhythmic auditory stimulation on gait kinematic parameters of patients with multiple sclerosis.

PubMed

Shahraki, M; Sohrabi, M; Taheri Torbati, H R; Nikkhah, K; NaeimiKia, M

2017-01-01

Purpose: This study aimed to examine the effect of rhythmic auditory stimulation on gait kinematic parameters of patients with multiple sclerosis. Subjects and Methods: In this study, 18 subjects, comprising 4 males and 14 females with Multiple Sclerosis with expanded disability status scale of 3 to 6 were chosen. Subjects were selected by available and targeted sampling and were randomly divided into two experimental (n = 9) and control (n = 9) groups. Exercises were gait with rhythmic auditory stimulation by a metronome device, in addition to gait without stimulation for the experimental and control groups, respectively. Training was carried out for 3 weeks, with 30 min duration for each session 3 times a week. Stride length, stride time, double support time, cadence and gait speed were measured by motion analysis device. Results: There was a significant difference between stride length, stride time, double support time, cadence and gait speed in the experimental group, before and after the training. Furthermore, there was a significant difference between the experimental and control groups in the enhancement of stride length, stride time, cadence and gait speed in favor of the experimental group. While this difference was not significant for double support time. Conclusion: The results of this study showed that rhythmic auditory stimulation is an effective rehabilitation method to improve gait kinematic parameters in patients with multiple sclerosis.

Fast concurrent array-based stacks, queues and deques using fetch-and-increment-bounded, fetch-and-decrement-bounded and store-on-twin synchronization primitives

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

Chen, Dong; Gara, Alana; Heidelberger, Philip

Implementation primitives for concurrent array-based stacks, queues, double-ended queues (deques) and wrapped deques are provided. In one aspect, each element of the stack, queue, deque or wrapped deque data structure has its own ticket lock, allowing multiple threads to concurrently use multiple elements of the data structure and thus achieving high performance. In another aspect, new synchronization primitives FetchAndIncrementBounded (Counter, Bound) and FetchAndDecrementBounded (Counter, Bound) are implemented. These primitives can be implemented in hardware and thus promise a very fast throughput for queues, stacks and double-ended queues.

Blade pitch optimization methods for vertical-axis wind turbines

NASA Astrophysics Data System (ADS)

Kozak, Peter

Vertical-axis wind turbines (VAWTs) offer an inherently simpler design than horizontal-axis machines, while their lower blade speed mitigates safety and noise concerns, potentially allowing for installation closer to populated and ecologically sensitive areas. While VAWTs do offer significant operational advantages, development has been hampered by the difficulty of modeling the aerodynamics involved, further complicated by their rotating geometry. This thesis presents results from a simulation of a baseline VAWT computed using Star-CCM+, a commercial finite-volume (FVM) code. VAWT aerodynamics are shown to be dominated at low tip-speed ratios by dynamic stall phenomena and at high tip-speed ratios by wake-blade interactions. Several optimization techniques have been developed for the adjustment of blade pitch based on finite-volume simulations and streamtube models. The effectiveness of the optimization procedure is evaluated and the basic architecture for a feedback control system is proposed. Implementation of variable blade pitch is shown to increase a baseline turbine's power output between 40%-100%, depending on the optimization technique, improving the turbine's competitiveness when compared with a commercially-available horizontal-axis turbine.

Variable Pitch Darrieus Water Turbines

NASA Astrophysics Data System (ADS)

Kirke, Brian; Lazauskas, Leo

In recent years the Darrieus wind turbine concept has been adapted for use in water, either as a hydrokinetic turbine converting the kinetic energy of a moving fluid in open flow like an underwater wind turbine, or in a low head or ducted arrangement where flow is confined, streamtube expansion is controlled and efficiency is not subject to the Betz limit. Conventional fixed pitch Darrieus turbines suffer from two drawbacks, (i) low starting torque and (ii) shaking due to cyclical variations in blade angle of attack. Ventilation and cavitation can also cause problems in water turbines when blade velocities are high. Shaking can be largely overcome by the use of helical blades, but these do not produce large starting torque. Variable pitch can produce high starting torque and high efficiency, and by suitable choice of pitch regime, shaking can be minimized but not entirely eliminated. Ventilation can be prevented by avoiding operation close to a free surface, and cavitation can be prevented by limiting blade velocities. This paper summarizes recent developments in Darrieus water turbines, some problems and some possible solutions.

Momentum considerations on the New MEXICO experiment

NASA Astrophysics Data System (ADS)

Parra, E. A.; Boorsma, K.; Schepers, J. G.; Snel, H.

2016-09-01

The present paper regards axial and angular momentum considerations combining detailed loads from pressure sensors and the flow field mapped with particle image velocimetry (PIV) techniques. For this end, the study implements important results leaning on experimental data from wind tunnel measurements of the New MEXICO project. The measurements, taken on a fully instrumented rotor, were carried out in the German Dutch Wind tunnel Organisation (DNW) testing the MEXICO rotor in the open section. The work revisits the so-called momentum theory, showing that the integral thrust and torque measured on the rotor correspond with an extent of 0.7 and 2.4% respectively to the momentum balance of the global flow field using the general momentum equations. Likewise, the sectional forces combined with the local induced velocities are found to plausibly obey the annular streamtube theory, albeit some limitations in the axial momentum become more apparent at high inductions after a=0.3. Finally, azimuth induced velocities are measured and compared to predictions from models of Glauert and Burton et al., showing close-matching forecasts for blade spans above 25%.

Modeling distortion of HIT by an Actuator Disk in a periodic domain

NASA Astrophysics Data System (ADS)

Ghate, Aditya; Ghaisas, Niranjan; Lele, Sanjiva

2017-11-01

We study the distortion of incompressible, homogeneous isotropic turbulence (HIT) by a dragging actuator disk with a fixed thrust coefficient (under the large Reynolds number limit), using Large Eddy Simulation (LES). The HIT inflow is tailored to ensure that the largest length scales in the flow are smaller than the actuator disk diameter in order to minimize the meandering of the turbulent wake and isolate the length scales that undergo distortion. The numerical scheme (Fourier collocation with dealiasing) and the SGS closure (anisotropic minimum dissipation model) are carefully selected to minimize numerical artifacts expected due to the inviscid assumption. The LES is used to characterize the following 3 properties of the flow a) distortion of HIT due to the expanding streamtube resulting in strong anisotropy, b) turbulent pressure modulation across the actuator disk, and the c) turbulent wake state. Finally, we attempt to model the initial distortion and the pressure modulation using a WKB variant of RDT solved numerically using a set of discrete Gabor modes. Funding provided by Precourt Institute for Energy at Stanford University.

Scramjet Tests in a Shock Tunnel at Flight Mach 7, 10, and 15 Conditions

NASA Technical Reports Server (NTRS)

Rogers, R. C.; Shih, A. T.; Tsai, C.-Y.; Foelsche, R. O.

2001-01-01

Tests of the Hyper-X scramjet engine flowpath have been conducted in the HYPULSE shock tunnel at conditions duplicating the stagnation enthalpy at flight Mach 7, 10, and 15. For the tests at Mach 7 and 10 HYPULSE was operated as a reflected-shock tunnel; at the Mach 15 condition, HYPULSE was operated as a shock-expansion tunnel. The test conditions matched the stagnation enthalpy of a scramjet engine on an aerospace vehicle accelerating through the atmosphere along a 1000 psf dynamic pressure trajectory. Test parameter variation included fuel equivalence ratios from lean (0.8) to rich (1.5+); fuel composition from pure hydrogen to mixtures of 2% and 5% silane in hydrogen by volume; and inflow pressure and Mach number made by changing the scramjet model mounting angle in the HYPULSE test chamber. Data sources were wall pressures and heat flux distributions and schlieren and fuel plume imaging in the combustor/nozzle sections. Data are presented for calibration of the facility nozzles and the scramjet engine model. Comparisons of pressure distributions and flowpath streamtube performance estimates are made for the three Mach numbers tested.

Computer analysis of flow perturbations generated by placement of choke bumps in a wind tunnel

NASA Technical Reports Server (NTRS)

Campbell, R. L.

1981-01-01

An inviscid analytical study was conducted to determine the upstream flow perturbations caused by placing choke bumps in a wind tunnel. A computer program based on the stream-tube curvature method was used to calculate the resulting flow fields for a nominal free-stream Mach number range of 0.6 to 0.9. The choke bump geometry was also varied to investigate the effect of bump shape on the disturbance produced. Results from the study indicate that a region of significant variation from the free-stream conditions exists upstream of the throat of the tunnel. The extent of the disturbance region was, as a rule, dependent on Mach number and the geometry of the choke bump. In general, the upstream disturbance distance decreased for increasing nominal free-stream Mach number and for decreasing length-to-height ratio of the bump. A polynomial-curve choke bump usually produced less of a disturbance than did a circular-arc bump and going to an axisymmetric configuration (modeling choke bumps on all the tunnel walls) generally resulted in a lower disturbance than with the corresponding two dimensional case.

Multiple victimizations before and after leaving home associated with PTSD, depression, and substance use disorder among homeless youth.

PubMed

Bender, Kimberly; Brown, Samantha M; Thompson, Sanna J; Ferguson, Kristin M; Langenderfer, Lisa

2015-05-01

Exposure to multiple forms of maltreatment during childhood is associated with serious mental health consequences among youth in the general population, but limited empirical attention has focused on homeless youth-a population with markedly high rates of childhood maltreatment followed by elevated rates of street victimization. This study investigated the rates of multiple childhood abuses (physical, sexual, and emotional abuse) and multiple street victimizations (robbery, physical assault, and sexual assault) and examined their relative relationships to mental health outcomes (meeting Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision, criteria for post-traumatic stress disorder [PTSD], depression, and substance use disorder) among a large (N = 601) multisite sample of homeless youth. Approximately 79% of youth retrospectively reported multiple childhood abuses (two or more types) and 28% reported multiple street victimizations (two or more types). Each additional type of street victimization nearly doubled youths' odds for meeting criteria for substance use disorder. Furthermore, each additional type of childhood abuse experienced more than doubled youths' odds for meeting criteria for PTSD. Both multiple abuses and multiple street victimizations were associated with an approximate twofold increase in meeting depression criteria. Findings suggest the need for screening, assessment, and trauma-informed services for homeless youth who consider multiple types of abuse and victimization experiences. © The Author(s) 2014.

Frequency doubling of an InGaAs multiple quantum wells semiconductor disk laser

NASA Astrophysics Data System (ADS)

Lidan, Jiang; Renjiang, Zhu; Maohua, Jiang; Dingke, Zhang; Yuting, Cui; Peng, Zhang; Yanrong, Song

2018-01-01

We demonstrate a good beam quality 483 nm blue coherent radiation from a frequency doubled InGaAs multiple quantum wells semiconductor disk laser. The gain chip is consisted of 6 repeats of strain uncompensated InGaAs/GaAs quantum wells and 25 pairs of GaAs/AlAs distributed Bragg reflector. A 4 × 4 × 7 mm3 type I phase-matched BBO nonlinear crystal is used in a V-shaped laser cavity for the second harmonic generation, and 210 mW blue output power is obtained when the absorbed pump power is 3.5 W. The M2 factors of the laser beam in x and y directions are about 1.04 and 1.01, respectively. The output power of the blue laser is limited by the relatively small number of the multiple quantum wells, and higher power can be expected by increasing the number of the multiple quantum wells and improving the heat management of the laser.

Radial velocities of southern visual multiple stars

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

Tokovinin, Andrei; Pribulla, Theodor; Fischer, Debra, E-mail: atokovinin@ctio.noao.edu, E-mail: pribulla@ta3.sk, E-mail: debra.fischer@gmail.com

2015-01-01

High-resolution spectra of visual multiple stars were taken in 2008–2009 to detect or confirm spectroscopic subsystems and to determine their orbits. Radial velocities of 93 late-type stars belonging to visual multiple systems were measured by numerical cross-correlation. We provide the individual velocities, the width, and the amplitude of the Gaussians that approximate the correlations. The new information on the multiple systems resulting from these data is discussed. We discovered double-lined binaries in HD 41742B, HD 56593C, and HD 122613AB, confirmed several other known subsystems, and constrained the existence of subsystems in some visual binaries where both components turned out tomore » have similar velocities. The orbits of double-lined subsystems with periods of 148 and 13 days are computed for HD 104471 Aa,Ab and HD 210349 Aa,Ab, respectively. We estimate individual magnitudes and masses of the components in these triple systems and update the outer orbit of HD 104471 AB.« less

Development of a Research Reactor Protocol for Neutron Multiplication Measurements

DOE PAGES

Arthur, Jennifer Ann; Bahran, Rian Mustafa; Hutchinson, Jesson D.; ...

2018-03-20

A new series of subcritical measurements has been conducted at the zero-power Walthousen Reactor Critical Facility (RCF) at Rensselaer Polytechnic Institute (RPI) using a 3He neutron multiplicity detector. The Critical and Subcritical 0-Power Experiment at Rensselaer (CaSPER) campaign establishes a protocol for advanced subcritical neutron multiplication measurements involving research reactors for validation of neutron multiplication inference techniques, Monte Carlo codes, and associated nuclear data. There has been increased attention and expanded efforts related to subcritical measurements and analyses, and this work provides yet another data set at known reactivity states that can be used in the validation of state-of-the-art Montemore » Carlo computer simulation tools. The diverse (mass, spatial, spectral) subcritical measurement configurations have been analyzed to produce parameters of interest such as singles rates, doubles rates, and leakage multiplication. MCNP ®6.2 was used to simulate the experiment and the resulting simulated data has been compared to the measured results. Comparison of the simulated and measured observables (singles rates, doubles rates, and leakage multiplication) show good agreement. This work builds upon the previous years of collaborative subcritical experiments and outlines a protocol for future subcritical neutron multiplication inference and subcriticality monitoring measurements on pool-type reactor systems.« less

Development of a Research Reactor Protocol for Neutron Multiplication Measurements

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

Arthur, Jennifer Ann; Bahran, Rian Mustafa; Hutchinson, Jesson D.

A new series of subcritical measurements has been conducted at the zero-power Walthousen Reactor Critical Facility (RCF) at Rensselaer Polytechnic Institute (RPI) using a 3He neutron multiplicity detector. The Critical and Subcritical 0-Power Experiment at Rensselaer (CaSPER) campaign establishes a protocol for advanced subcritical neutron multiplication measurements involving research reactors for validation of neutron multiplication inference techniques, Monte Carlo codes, and associated nuclear data. There has been increased attention and expanded efforts related to subcritical measurements and analyses, and this work provides yet another data set at known reactivity states that can be used in the validation of state-of-the-art Montemore » Carlo computer simulation tools. The diverse (mass, spatial, spectral) subcritical measurement configurations have been analyzed to produce parameters of interest such as singles rates, doubles rates, and leakage multiplication. MCNP ®6.2 was used to simulate the experiment and the resulting simulated data has been compared to the measured results. Comparison of the simulated and measured observables (singles rates, doubles rates, and leakage multiplication) show good agreement. This work builds upon the previous years of collaborative subcritical experiments and outlines a protocol for future subcritical neutron multiplication inference and subcriticality monitoring measurements on pool-type reactor systems.« less

Search for neutrinoless double-electron capture of 156Dy

NASA Astrophysics Data System (ADS)

Finch, S. W.; Tornow, W.

2015-12-01

Background: Multiple large collaborations are currently searching for neutrinoless double-β decay, with the ultimate goal of differentiating the Majorana-Dirac nature of the neutrino. Purpose: Investigate the feasibility of resonant neutrinoless double-electron capture, an experimental alternative to neutrinoless double-β decay. Method: Two clover germanium detectors were operated underground in coincidence to search for the de-excitation γ rays of 156Gd following the neutrinoless double-electron capture of 156Dy. 231.95 d of data were collected at the Kimballton underground research facility with a 231.57 mg enriched 156Dy sample. Results: No counts were seen above background and half-life limits are set at O (1016-1018) yr for the various decay modes of 156Dy. Conclusion: Low background spectra were efficiently collected in the search for neutrinoless double-electron capture of 156Dy, although the low natural abundance and associated lack of large quantities of enriched samples hinders the experimental reach.

Self-assembly of a double-helical complex of sodium.

PubMed

Bell, T W; Jousselin, H

1994-02-03

Spontaneous self-organization of helical and multiple-helical molecular structures occurs on several levels in living organisms. Key examples are alpha-helical polypeptides, double-helical nucleic acids and helical protein structures, including F-actin, microtubules and the protein sheath of the tobacco mosaic virus. Although the self-assembly of double-helical transition-metal complexes bears some resemblance to the molecular organization of double-stranded DNA, selection between monohelical, double-helical and triple-helical structures is determined largely by the size and geometrical preference of the tightly bound metal. Here we present an example of double-helical assembly induced by the weaker and non-directional interactions of an alkali-metal ion with an organic ligand that is pre-organized into a coil. We have characterized the resulting complex by two-dimensional NMR and fast-atom-bombardment mass spectrometry. These results provide a step toward the creation of molecular tubes or ion channels consisting of intertwined coils.

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

Baart, T. A.; Vandersypen, L. M. K.; Kavli Institute of Nanoscience, Delft University of Technology, P.O. Box 5046, 2600 GA Delft

We report the computer-automated tuning of gate-defined semiconductor double quantum dots in GaAs heterostructures. We benchmark the algorithm by creating three double quantum dots inside a linear array of four quantum dots. The algorithm sets the correct gate voltages for all the gates to tune the double quantum dots into the single-electron regime. The algorithm only requires (1) prior knowledge of the gate design and (2) the pinch-off value of the single gate T that is shared by all the quantum dots. This work significantly alleviates the user effort required to tune multiple quantum dot devices.

Investigating the development of double-peak subauroral ion drift (DSAID)

NASA Astrophysics Data System (ADS)

Horvath, Ildiko; Lovell, Brian C.

2017-04-01

This study focuses on the newly described ionospheric feature, called double-peak subauroral ion drift (DSAID), which is a subclass of the well-known single-peak SAID. Double-layer Region 2 (R2) field aligned currents (FACs) could be the main driver of DSAID. Our aim is to gain new insights into the development of DSAID during its two-stage progression. Observational results are provided by five scenarios, each demonstrating a certain progression sequence of DSAID. Results show that SAID/DSAID occurred during flux transfer events and was accompanied by flow channels (FCs) associated with dayside magnetopause (FC-2) and nightside magnetotail (FC-3) reconnections, with westward electrojet (eastward FC), and with auroral streamers (FC-4). In the premidnight magnetic local time (MLT) sector of stage 2, DSAID development was due to the short-circuiting of the reconnection-injected plasma jets during substorms or pseudobreakups. Thus, the related ring current pressure buildup enhanced the downward R2 FACs leading to double/multiple circuits forming double-layer R2 FACs. During the midnight MLT hours of stage 2, DSAID development was closely related to the westward traveling surge (WTS)/substorm current wedge (SCW). WTS/SCW-related strong upward R1 FACs closed with meriodional currents producing eastward and downward (i.e., downward R2 FAC-style) return currents enhancing the downward R2 FACs and thus leading to double/multiple circuits forming double-layer R2 FACs. Auroral streamers/FC-4 represent a substorm substructure and their occurrence with DSAID after stage 2 demonstrates that this substructure occasionally includes DSAID. Our results demonstrate also that the short-circuited system underlying SAID/DSAID acted sometimes as a current generator and sometimes as a voltage generator.

The concept of double inlet-double outlet right ventricle: a distinct congenital heart disease.

PubMed

Spadotto, Veronica; Frescura, Carla; Ho, Siew Yen; Thiene, Gaetano

The aim of this study was to estimate the incidence and to analyze the anatomy of double inlet-double outlet right ventricle complex and its associated cardiac anomalies in our autopsy series. Among the 1640 hearts with congenital heart disease of our Anatomical Collection, we reviewed the specimens with double inlet-double outlet right ventricle, according to the sequential-segmental analysis, identifying associated cardiac anomalies and examining lung histology to assess the presence of pulmonary vascular disease. We identified 14 hearts with double inlet-double outlet right ventricle (0.85%). Right atrial isomerism was observed in 10 hearts, situs solitus in 3 and left atrial isomerism in one. Regarding the mode of atrioventricular connection, all hearts but one had a common atrioventricular valve. Systemic or pulmonary venous abnormalities were noted in all patients with atrial isomerism. In nine patients a valvular or subvalvular pulmonary stenosis was present. Among the functionally "univentricular hearts", double inlet- double outlet right ventricle represents a peculiar entity, mostly in association with right atrial isomerism. Multiple cardiac anomalies are associated and may complicate surgical repair. Copyright © 2016 Elsevier Inc. All rights reserved.

Microfluidic preparation and self diffusion PFG-NMR analysis of monodisperse water-in-oil-in-water double emulsions.

PubMed

Hughes, Eric; Maan, Abid Aslam; Acquistapace, Simone; Burbidge, Adam; Johns, Michael L; Gunes, Deniz Z; Clausen, Pascal; Syrbe, Axel; Hugo, Julien; Schroen, Karin; Miralles, Vincent; Atkins, Tim; Gray, Richard; Homewood, Philip; Zick, Klaus

2013-01-01

Monodisperse water-in-oil-in-water (WOW) double emulsions have been prepared using microfluidic glass devices designed and built primarily from off the shelf components. The systems were easy to assemble and use. They were capable of producing double emulsions with an outer droplet size from 100 to 40 μm. Depending on how the devices were operated, double emulsions containing either single or multiple water droplets could be produced. Pulsed-field gradient self-diffusion NMR experiments have been performed on the monodisperse water-in-oil-in-water double emulsions to obtain information on the inner water droplet diameter and the distribution of the water in the different phases of the double emulsion. This has been achieved by applying regularization methods to the self-diffusion data. Using these methods the stability of the double emulsions to osmotic pressure imbalance has been followed by observing the change in the size of the inner water droplets over time. Copyright © 2012 Elsevier Inc. All rights reserved.

Double- and Triple-Duty Caregiving Men: An Examination of Subjective Stress and Perceived Schedule Control.

PubMed

DePasquale, Nicole; Zarit, Steven H; Mogle, Jacqueline; Moen, Phyllis; Hammer, Leslie B; Almeida, David M

2018-04-01

Based on the stress process model of family caregiving, this study examined subjective stress appraisals and perceived schedule control among men employed in the long-term care industry (workplace-only caregivers) who concurrently occupied unpaid family caregiving roles for children (double-duty child caregivers), older adults (double-duty elder caregivers), and both children and older adults (triple-duty caregivers). Survey responses from 123 men working in nursing home facilities in the United States were analyzed using multiple linear regression models. Results indicated that workplace-only and double- and triple-duty caregivers' appraised primary stress similarly. However, several differences emerged with respect to secondary role strains, specifically work-family conflict, emotional exhaustion, and turnover intentions. Schedule control also constituted a stress buffer for double- and triple-duty caregivers, particularly among double-duty elder caregivers. These findings contribute to the scarce literature on double- and triple-duty caregiving men and have practical implications for recruitment and retention strategies in the health care industry.

Double Star Measurements at the Internationale Amateur Sternwarte (IAS) in Namibia in 2009

NASA Astrophysics Data System (ADS)

Anton, Rainer

2012-01-01

This paper is a continuation of earlier work published in JDSO in 2010. Using a 40-cm-Cassegrain telescope in Namibia and a fast CCD camera, 87 double and multiple systems were recorded and analyzed with the technique of "lucky imaging". Measurements are compared with literature data. Some noteworthy systems are discussed in more detail.

Generating multi-double-scroll attractors via nonautonomous approach

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

Hong, Qinghui; Xie, Qingguo, E-mail: qgxie@mail.hust.edu.cn; Shen, Yi

It is a common phenomenon that multi-scroll attractors are realized by introducing the various nonlinear functions with multiple breakpoints in double scroll chaotic systems. Differently, we present a nonautonomous approach for generating multi-double-scroll attractors (MDSA) without changing the original nonlinear functions. By using the multi-level-logic pulse excitation technique in double scroll chaotic systems, MDSA can be generated. A Chua's circuit, a Jerk circuit, and a modified Lorenz system are given as designed example and the Matlab simulation results are presented. Furthermore, the corresponding realization circuits are designed. The Pspice results are in agreement with numerical simulation results, which verify themore » availability and feasibility of this method.« less

Suppressing longitudinal double-layer oscillations by using elliptically polarized laser pulses in the hole-boring radiation pressure acceleration regime

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

Wu Dong; Yan, X. Q.; Key Laboratory of High Energy Density Physics Simulation, Ministry of Education, Peking University, Beijing 100871

It is shown that well collimated mono-energetic ion beams with a large particle number can be generated in the hole-boring radiation pressure acceleration regime by using an elliptically polarized laser pulse with appropriate theoretically determined laser polarization ratio. Due to the J Multiplication-Sign B effect, the double-layer charge separation region is imbued with hot electrons that prevent ion pileup, thus suppressing the double-layer oscillations. The proposed mechanism is well confirmed by Particle-in-Cell simulations, and after suppressing the longitudinal double-layer oscillations, the ion beams driven by the elliptically polarized lasers own much better energy spectrum than those by circularly polarized lasers.

Multiple-Barrier Resonant Tunneling Structures for Application in a Microwave Generator Stabilized by Microstrip Resonator

DTIC Science & Technology

2000-06-23

conductivity ( NDC ) effects in double barrier resonant tunneling structures (DBRTS) prove the extremely fast frequency response of charge transport (less...UNCLASSIFIED Defense Technical Information Center Compilation Part Notice ADP013131 TITLE: Multiple-Barrier Resonant Tunneling Structures for...Institute Multiple-barrier resonant tunneling structures for application in a microwave generator stabilized by microstrip resonator S. V. Evstigneev, A. L

Multiple locations of nerve compression: an unusual cause of persistent lower limb paresthesia.

PubMed

Ang, Chia-Liang; Foo, Leon Siang Shen

2014-01-01

A paucity of appreciation exists that the "double crush" phenomenon can account for persistent leg symptoms even after spinal neural decompression surgery. We present an unusual case of multiple locations of nerve compression causing persistent lower limb paresthesia in a 40-year old male patient. The patient's lower limb paresthesia was persistent after an initial spinal surgery to treat spinal lateral recess stenosis thought to be responsible for the symptoms. It was later discovered that he had peroneal muscle herniations that had caused superficial peroneal nerve entrapments at 2 separate locations. The patient obtained much symptomatic relief after decompression of the peripheral nerve. The "double crush" phenomenon and multiple levels of nerve compression should be considered when evaluating lower limb neurogenic symptoms, especially after spinal nerve root surgery. Copyright © 2014 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

Design and optimization of LTE 1800 MIMO antenna.

PubMed

Wong, Huey Shin; Islam, Mohammad Tariqul; Kibria, Salehin

2014-01-01

A multiple input and multiple output (MIMO) antenna that comprises a printed microstrip antenna and a printed double-L sleeve monopole antenna for LTE 1800 wireless application is presented. The printed double-L sleeve monopole antenna is fed by a 50 ohm coplanar waveguide (CPW). A novel T-shaped microstrip feedline printed on the other side of the PCB is used to excite the waveguide's outer shell. Isolation characteristics better than -15 dB can be obtained for the proposed MIMO antenna. The proposed antenna can operate in LTE 1800 (1710 MHz-1880 MHz). This antenna exhibits omnidirectional characteristics. The efficiency of the antenna is greater than 70% and has high gain of 2.18 dBi.

Double Coaxial Microcatheter Technique for Glue Embolization of Renal Arteriovenous Malformations

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

Uchikawa, Yoko, E-mail: jauchikawa@gmail.com; Mori, Kensaku, E-mail: moriken@md.tsukuba.ac.jp; Shiigai, Masanari, E-mail: m-41gai@yahoo.co.jp

PurposeTo demonstrate the technical benefit of the double coaxial microcatheter technique for embolization of renal arteriovenous malformations (AVMs) with n-butyl cyanoacrylate and iodized oil (glue).Materials and MethodsSix consecutive patients (1 man and 5 women; mean age 61 years; range 44–77 years) with renal AVMs were included. Five patients had hematuria, and one had a risk of heart failure due to a large intrarenal arteriovenous shunt. All patients underwent transarterial embolization using glue and the double coaxial microcatheter technique with outer 2.6F and inner 1.9F microcatheters. After glue injection, the inner microcatheter was retracted, while the outer microcatheter was retained. We assessed themore » complications and clinical outcomes of this technique.ResultsTechnical success was achieved in all patients. In 9 sessions, 34 feeding arteries were embolized with glue using the double coaxial microcatheter technique, 1 was embolized with glue using a single microcatheter, and 2 were embolized with coils. The double coaxial microcatheter technique was useful for selecting small tortuous feeding arteries, preventing glue reflux to the proximal arteries, and approaching multiple feeding arteries without complete retraction of the microcatheters. As a minor complication, glue migrated into the venous system in four patients without any sequelae. In all patients, favorable clinical outcomes, including hematuria cessation in five patients and improvement of the large intrarenal arteriovenous shunt in one patient, were obtained without deterioration of renal function.ConclusionGlue embolization with the double coaxial microcatheter technique was useful for treating renal AVMs with multiple tortuous feeding arteries.« less

Monoclonal gammopathy with double M-bands: An atypical presentation on serum protein electrophoresis simulating biclonal gammopathy.

PubMed

Bora, Kaustubh; Das, Umesh; Barman, Bhupen; Ruram, Alice Abraham

2017-01-01

Monoclonal gammopathies, such as multiple myeloma, typically exhibit high levels of a monoclonal immunoglobulin (M-protein), produced by a clone of abnormally proliferating B-lymphocytes and/or plasma cells. The M-protein can be evaluated by serum protein electrophoresis (SPEP), which yields a single discrete band (M-band), usually in the γ-globulin region. Rarely, two M-bands appear simultaneously at different positions during SPEP - a condition known as biclonal gammopathy, which is a result of clonal expansion of two different neoplastic cell lines. Here, we describe an atypical case of IgA-λ multiple myeloma, where double M-bands (one in β- and the other in γ-globulin region) were found during SPEP simulating biclonal gammopathy, although it was monoclonal in nature. This peculiar presentation of double M-bands in monoclonal gammopathy was attributed to polymeric forms of IgA by systematic workup. Further, we discuss how true and apparent biclonality can be distinguished by inexpensive analytical techniques in resource-constrained settings.

Double-image storage optimized by cross-phase modulation in a cold atomic system

NASA Astrophysics Data System (ADS)

Qiu, Tianhui; Xie, Min

2017-09-01

A tripod-type cold atomic system driven by double-probe fields and a coupling field is explored to store double images based on the electromagnetically induced transparency (EIT). During the storage time, an intensity-dependent signal field is applied further to extend the system with the fifth level involved, then the cross-phase modulation is introduced for coherently manipulating the stored images. Both analytical analysis and numerical simulation clearly demonstrate a tunable phase shift with low nonlinear absorption can be imprinted on the stored images, which effectively can improve the visibility of the reconstructed images. The phase shift and the energy retrieving rate of the probe fields are immune to the coupling intensity and the atomic optical density. The proposed scheme can easily be extended to the simultaneous storage of multiple images. This work may be exploited toward the end of EIT-based multiple-image storage devices for all-optical classical and quantum information processings.

Synchronized parameter optimization of the double freeform lenses illumination system used for the CF-LCoS pico-projectors

NASA Astrophysics Data System (ADS)

Chen, Enguo; Liu, Peng; Yu, Feihong

2012-10-01

A novel synchronized optimization method of multiple freeform surfaces is proposed and applied to double lenses illumination system design of CF-LCoS pico-projectors. Based on Snell's law and the energy conservation law, a series of first-order partial differential equations are derived for the multiple freeform surfaces of the initial system. By assigning the light deflection angle to each freeform surface, multiple surfaces can be obtained simultaneously by solving the corresponding equations, meanwhile the restricted angle on CF-LCoS is guaranteed. In order to improve the spatial uniformity, the multi-surfaces are synchronously optimized by using simplex algorithm for an extended LED source. Design example shows that the double lenses based illumination system, which employs a single 2 mm×2 mm LED chip and a CF-LCoS panel with a diagonal of 0.59 inches satisfies the needs of pico-projector. Moreover, analytical result indicates that the design method represents substantial improvement and practical significance over traditional CF-LCoS projection system, which could offer outstanding performance with both portability and low cost. The synchronized optimization design method could not only realize collimating and uniform illumination, but also could be introduced to other specific light conditions.

Unified double- and single-sided homogeneous Green’s function representations

PubMed Central

van der Neut, Joost; Slob, Evert

2016-01-01

In wave theory, the homogeneous Green’s function consists of the impulse response to a point source, minus its time-reversal. It can be represented by a closed boundary integral. In many practical situations, the closed boundary integral needs to be approximated by an open boundary integral because the medium of interest is often accessible from one side only. The inherent approximations are acceptable as long as the effects of multiple scattering are negligible. However, in case of strongly inhomogeneous media, the effects of multiple scattering can be severe. We derive double- and single-sided homogeneous Green’s function representations. The single-sided representation applies to situations where the medium can be accessed from one side only. It correctly handles multiple scattering. It employs a focusing function instead of the backward propagating Green’s function in the classical (double-sided) representation. When reflection measurements are available at the accessible boundary of the medium, the focusing function can be retrieved from these measurements. Throughout the paper, we use a unified notation which applies to acoustic, quantum-mechanical, electromagnetic and elastodynamic waves. We foresee many interesting applications of the unified single-sided homogeneous Green’s function representation in holographic imaging and inverse scattering, time-reversed wave field propagation and interferometric Green’s function retrieval. PMID:27436983

Unified double- and single-sided homogeneous Green's function representations

NASA Astrophysics Data System (ADS)

Wapenaar, Kees; van der Neut, Joost; Slob, Evert

2016-06-01

In wave theory, the homogeneous Green's function consists of the impulse response to a point source, minus its time-reversal. It can be represented by a closed boundary integral. In many practical situations, the closed boundary integral needs to be approximated by an open boundary integral because the medium of interest is often accessible from one side only. The inherent approximations are acceptable as long as the effects of multiple scattering are negligible. However, in case of strongly inhomogeneous media, the effects of multiple scattering can be severe. We derive double- and single-sided homogeneous Green's function representations. The single-sided representation applies to situations where the medium can be accessed from one side only. It correctly handles multiple scattering. It employs a focusing function instead of the backward propagating Green's function in the classical (double-sided) representation. When reflection measurements are available at the accessible boundary of the medium, the focusing function can be retrieved from these measurements. Throughout the paper, we use a unified notation which applies to acoustic, quantum-mechanical, electromagnetic and elastodynamic waves. We foresee many interesting applications of the unified single-sided homogeneous Green's function representation in holographic imaging and inverse scattering, time-reversed wave field propagation and interferometric Green's function retrieval.

Effect of mood states and infertility stress on patients' attitudes toward embryo transfer and multiple pregnancy.

PubMed

Newton, Christopher; Feyles, Valter; Asgary-Eden, Veronica

2013-08-01

To examine whether mood state or infertility stress influences perceptions of risk, preferences for embryo transfer, or views on multiple pregnancy. Observational cohort study. Hospital-based fertility clinic. One hundred seventy-six women participating in IVF treatment. None. Mood scores, ratings of risk, preference for multiple embryo transfer, and attitudes toward multiple pregnancy. Growing feelings of tension across the cycle corresponded with increases in the perceived riskiness of double-embryo transfer, but there was no change in strength of transfer preferences. Women experiencing negative moods, such as depression, viewed twin and triplet pregnancy as less likely, whereas increasing positive feelings across the cycle were associated with increasing desire for twin pregnancy. Overall, women perceived double- and triple-embryo transfer as less risky by cycle end than at cycle beginning and felt more certain about multiple-embryo transfer. The dyssynchrony observed among changes in mood, perceptions of risk, and transfer preferences challenges assumptions about the way medical risk information influences transfer preferences, and the findings suggest that mood states experienced during an IVF cycle might affect transfer preferences by influencing attitudes toward multiple pregnancy. Additional considerations beyond providing risk information are needed to facilitate effective patient decision making. Crown Copyright © 2013. Published by Elsevier Inc. All rights reserved.

Recessively inherited multiple epiphyseal dysplasia with normal stature, club foot, and double layered patella caused by a DTDST mutation

PubMed Central

Superti-Furga, A.; Neumann, L.; Riebel, T.; Eich, G.; Steinmann, B.; Spranger, J.; Kunze, J.

1999-01-01

We have observed over 25 different mutations in the diastrophic dysplasia sulphate transporter gene (DTDST) in association with the recessive disorders achondrogenesis 1B, atelosteogenesis 2, and diastrophic dysplasia. The c862t (R279W) transition is the most common mutation in non-Finnish patients, but in these disorders it is usually combined with other DTDST mutations. We had not seen a case of homozygosity for c862t (R279W) until we analysed DNA from a 36 year old male with tall-normal stature (180 cm) who asked for genetic counselling for suspected multiple epiphyseal dysplasia. He was treated for club foot and hip dysplasia at birth. Skeletal changes consistent with multiple epiphyseal dysplasia, with the peculiar finding of a double layered patella, were recognised during childhood. Cleft palate, swelling of the ear pinna, and hitch hiker thumb were absent. He was found to be homozygous, and both healthy parents heterozygous, for the R279W mutation in DTDST, and his fibroblasts showed a sulphate incorporation defect typical of DTDST disorders. Counselling was given for a recessive disorder, thereby considerably reducing the probability of affected offspring.
  Multiple epiphyseal dysplasia is more frequently caused by dominant mutations in the COMP (EDM1, McKusick 132400) and COL9A2 genes (EDM2, McKusick 600204). A few other patients and families with features similar to our proband have been described previously and considered to have autosomal recessive MED (EDM4, McKusick 226900). This observation confirms the existence of this entity and assigns it to the phenotypic spectrum associated with mutations at the DTDST locus.


Keywords: multiple epiphyseal dysplasia; DTDST; double layered patella PMID:10465113

Microfluidic approach for encapsulation via double emulsions.

PubMed

Wang, Wei; Zhang, Mao-Jie; Chu, Liang-Yin

2014-10-01

Double emulsions, with inner drops well protected by the outer shells, show great potential as compartmentalized systems to encapsulate multiple components for protecting actives, masking flavor, and targetedly delivering and controllably releasing drugs. Precise control of the encapsulation characteristics of each component is critical to achieve an optimal therapeutic efficacy for pharmaceutical applications. Such controllable encapsulation can be realized by using microfluidic approaches for producing monodisperse double emulsions with versatile and controllable structures as the encapsulation system. The size, number and composition of the emulsion drops can be accurately manipulated for optimizing the encapsulation of each component for pharmaceutical applications. In this review, we highlight the outstanding advantages of controllable microfluidic double emulsions for highly efficient and precisely controllable encapsulation. Copyright © 2014 Elsevier Ltd. All rights reserved.

Did Shakespeare write double falsehood? Identifying individuals by creating psychological signatures with text analysis.

PubMed

Boyd, Ryan L; Pennebaker, James W

2015-05-01

More than 100 years after Shakespeare's death, Lewis Theobald published Double Falsehood, a play supposedly sourced from a lost play by Shakespeare and John Fletcher. Since its release, scholars have attempted to determine its true authorship. Using new approaches to language and psychological analysis, we examined Double Falsehood and the works of Theobald, Shakespeare, and Fletcher. Specifically, we created a psychological signature from each author's language and statistically compared the features of each signature with those of Double Falsehood's signature. Multiple analytic approaches converged in suggesting that Double Falsehood's psychological style and content architecture predominantly resemble those of Shakespeare, showing some similarity with Fletcher's signature and only traces of Theobald's. Closer inspection revealed that Shakespeare's influence is most apparent early in the play, whereas Fletcher's is most apparent in later acts. Double Falsehood has a psychological signature consistent with that expected to be present in the long-lost play The History of Cardenio, cowritten by Shakespeare and Fletcher. © The Author(s) 2015.

Advanced Doubling Adding Method for Radiative Transfer in Planetary Atmospheres

NASA Astrophysics Data System (ADS)

Liu, Quanhua; Weng, Fuzhong

2006-12-01

The doubling adding method (DA) is one of the most accurate tools for detailed multiple-scattering calculations. The principle of the method goes back to the nineteenth century in a problem dealing with reflection and transmission by glass plates. Since then the doubling adding method has been widely used as a reference tool for other radiative transfer models. The method has never been used in operational applications owing to tremendous demand on computational resources from the model. This study derives an analytical expression replacing the most complicated thermal source terms in the doubling adding method. The new development is called the advanced doubling adding (ADA) method. Thanks also to the efficiency of matrix and vector manipulations in FORTRAN 90/95, the advanced doubling adding method is about 60 times faster than the doubling adding method. The radiance (i.e., forward) computation code of ADA is easily translated into tangent linear and adjoint codes for radiance gradient calculations. The simplicity in forward and Jacobian computation codes is very useful for operational applications and for the consistency between the forward and adjoint calculations in satellite data assimilation.

Multiplicity

DTIC Science & Technology

1991-04-01

that it has not adopted that test. 1 3 5 The Court did, however, recognize that the double Jeopardy protection includes a collateral estoppel feature... estoppel feature. 1 4 1 The Court articulated this new test in the following terms: The Double Jeopardy Clause bars any subsequent prosecution in which...126 Ashe v. Swenson, 397 U.S. at 452 (Brennan, J., concurring). 127 "We defined collateral estoppel as providing that ’when an issue of ultimate

Local Gate Control of a Carbon Nanotube Double Quantum Dot

DTIC Science & Technology

2016-04-04

Nanotube Double Quantum Dot N. Mason,*† M. J. Biercuk,* C. M. Marcus† We have measured carbon nanotube quantum dots with multiple electro- static gates and...computation. Carbon nanotubes have been considered lead- ing candidates for nanoscale electronic applica- tions (1, 2). Previous measurements of nano- tube...electronics have shown electron confine- ment (quantum dot) effects such as single- electron charging and energy-level quantization (3–5). Nanotube

Impact of SCBA size and fatigue from different firefighting work cycles on firefighter gait.

PubMed

Kesler, Richard M; Bradley, Faith F; Deetjen, Grace S; Angelini, Michael J; Petrucci, Matthew N; Rosengren, Karl S; Horn, Gavin P; Hsiao-Wecksler, Elizabeth T

2018-04-04

Risk of slips, trips and falls in firefighters maybe influenced by the firefighter's equipment and duration of firefighting. This study examined the impact of a four self-contained breathing apparatus (SCBA) three SCBA of increasing size and a prototype design and three work cycles one bout (1B), two bouts with a five-minute break (2B) and two bouts back-to-back (BB) on gait in 30 firefighters. Five gait parameters (double support time, single support time, stride length, step width and stride velocity) were examined pre- and post-firefighting activity. The two largest SCBA resulted in longer double support times relative to the smallest SCBA. Multiple bouts of firefighting activity resulted in increased single and double support time and decreased stride length, step width and stride velocity. These results suggest that with larger SCBA or longer durations of activity, firefighters may adopt more conservative gait patterns to minimise fall risk. Practitioner Summary: The effects of four self-contained breathing apparatus (SCBA) and three work cycles on five gait parameters were examined pre- and post-firefighting activity. Both SCBA size and work cycle affected gait. The two largest SCBA resulted in longer double support times. Multiple bouts of activity resulted in more conservative gait patterns.

Design and Optimization of LTE 1800 MIMO Antenna

PubMed Central

Wong, Huey Shin; Islam, Mohammad Tariqul

2014-01-01

A multiple input and multiple output (MIMO) antenna that comprises a printed microstrip antenna and a printed double-L sleeve monopole antenna for LTE 1800 wireless application is presented. The printed double-L sleeve monopole antenna is fed by a 50 ohm coplanar waveguide (CPW). A novel T-shaped microstrip feedline printed on the other side of the PCB is used to excite the waveguide's outer shell. Isolation characteristics better than −15 dB can be obtained for the proposed MIMO antenna. The proposed antenna can operate in LTE 1800 (1710 MHz–1880 MHz). This antenna exhibits omnidirectional characteristics. The efficiency of the antenna is greater than 70% and has high gain of 2.18 dBi. PMID:24967440

Integrated packaging of multiple double sided cooling planar bond power modules

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

Liang, Zhenxian

An integrated double sided cooled power module has one or multiple phase legs configuration including one or more planar power packages, each planar power package having an upper power switch unit and a lower power switch unit directly bonded and interconnected between two insulated power substrates, and further sandwiched between two heat exchangers via direct bonds. A segmented coolant manifold is interposed with the one or more planar power packages and creates a sealed enclosure that defines a coolant inlet, a coolant outlet and a coolant flow path between the inlet and the outlet. A coolant circulates along the flowmore » path to remove heat and increase the power density of the power module.« less

Large neighborhood search for the double traveling salesman problem with multiple stacks

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

Bent, Russell W; Van Hentenryck, Pascal

This paper considers a complex real-life short-haul/long haul pickup and delivery application. The problem can be modeled as double traveling salesman problem (TSP) in which the pickups and the deliveries happen in the first and second TSPs respectively. Moreover, the application features multiple stacks in which the items must be stored and the pickups and deliveries must take place in reserve (LIFO) order for each stack. The goal is to minimize the total travel time satisfying these constraints. This paper presents a large neighborhood search (LNS) algorithm which improves the best-known results on 65% of the available instances and ismore » always within 2% of the best-known solutions.« less

Linearized inversion of multiple scattering seismic energy

NASA Astrophysics Data System (ADS)

Aldawood, Ali; Hoteit, Ibrahim; Zuberi, Mohammad

2014-05-01

Internal multiples deteriorate the quality of the migrated image obtained conventionally by imaging single scattering energy. So, imaging seismic data with the single-scattering assumption does not locate multiple bounces events in their actual subsurface positions. However, imaging internal multiples properly has the potential to enhance the migrated image because they illuminate zones in the subsurface that are poorly illuminated by single scattering energy such as nearly vertical faults. Standard migration of these multiples provides subsurface reflectivity distributions with low spatial resolution and migration artifacts due to the limited recording aperture, coarse sources and receivers sampling, and the band-limited nature of the source wavelet. The resultant image obtained by the adjoint operator is a smoothed depiction of the true subsurface reflectivity model and is heavily masked by migration artifacts and the source wavelet fingerprint that needs to be properly deconvolved. Hence, we proposed a linearized least-square inversion scheme to mitigate the effect of the migration artifacts, enhance the spatial resolution, and provide more accurate amplitude information when imaging internal multiples. The proposed algorithm uses the least-square image based on single-scattering assumption as a constraint to invert for the part of the image that is illuminated by internal scattering energy. Then, we posed the problem of imaging double-scattering energy as a least-square minimization problem that requires solving the normal equation of the following form: GTGv = GTd, (1) where G is a linearized forward modeling operator that predicts double-scattered seismic data. Also, GT is a linearized adjoint operator that image double-scattered seismic data. Gradient-based optimization algorithms solve this linear system. Hence, we used a quasi-Newton optimization technique to find the least-square minimizer. In this approach, an estimate of the Hessian matrix that contains curvature information is modified at every iteration by a low-rank update based on gradient changes at every step. At each iteration, the data residual is imaged using GT to determine the model update. Application of the linearized inversion to synthetic data to image a vertical fault plane demonstrate the effectiveness of this methodology to properly delineate the vertical fault plane and give better amplitude information than the standard migrated image using the adjoint operator that takes into account internal multiples. Thus, least-square imaging of multiple scattering enhances the spatial resolution of the events illuminated by internal scattering energy. It also deconvolves the source signature and helps remove the fingerprint of the acquisition geometry. The final image is obtained by the superposition of the least-square solution based on single scattering assumption and the least-square solution based on double scattering assumption.

Femtosecond laser-induced periodic surface structures on silicon upon polarization controlled two-color double-pulse irradiation.

PubMed

Höhm, Sandra; Herzlieb, Marcel; Rosenfeld, Arkadi; Krüger, Jörg; Bonse, Jörn

2015-01-12

Two-color double-fs-pulse experiments were performed on silicon wafers to study the temporally distributed energy deposition in the formation of laser-induced periodic surface structures (LIPSS). A Mach-Zehnder interferometer generated parallel or cross-polarized double-pulse sequences at 400 and 800 nm wavelength, with inter-pulse delays up to a few picoseconds between the sub-ablation 50-fs-pulses. Multiple two-color double-pulse sequences were collinearly focused by a spherical mirror to the sample. The resulting LIPSS characteristics (periods, areas) were analyzed by scanning electron microscopy. A wavelength-dependent plasmonic mechanism is proposed to explain the delay-dependence of the LIPSS. These two-color experiments extend previous single-color studies and prove the importance of the ultrafast energy deposition for LIPSS formation.

Auroral-particle precipitation and trapping caused by electrostatic double layers in the ionosphere.

PubMed

Albert, R D; Lindstrom, P J

1970-12-25

Interpretation of high-resolution angular distribution measurements of the primary auroral electron flux detected by a rocket probe launched into a visible aurora from Fort Churchill in the fall of 1966 leads to the following conclusions. The auroral electron flux is nearly monoenergetic and has a quasi-trapped as well as a precipitating component. The quasi-trapped flux appears to be limited to a region defined by magnetic-mirror points and multiple electrostatic double layers in the ionosphere. The electrostatic field of the double-layer distribution enhances the aurora by lowering the magnetic-mirror points and supplying energy to the primary auroral electrons.

Use of the false discovery rate for evaluating clinical safety data.

PubMed

Mehrotra, Devan V; Heyse, Joseph F

2004-06-01

Clinical adverse experience (AE) data are routinely evaluated using between group P values for every AE encountered within each of several body systems. If the P values are reported and interpreted without multiplicity considerations, there is a potential for an excess of false positive findings. Procedures based on confidence interval estimates of treatment effects have the same potential for false positive findings as P value methods. Excess false positive findings can needlessly complicate the safety profile of a safe drug or vaccine. Accordingly, we propose a novel method for addressing multiplicity in the evaluation of adverse experience data arising in clinical trial settings. The method involves a two-step application of adjusted P values based on the Benjamini and Hochberg false discovery rate (FDR). Data from three moderate to large vaccine trials are used to illustrate our proposed 'Double FDR' approach, and to reinforce the potential impact of failing to account for multiplicity. This work was in collaboration with the late Professor John W. Tukey who coined the term 'Double FDR'.

Development of a lithium fluoride zinc sulfide based neutron multiplicity counter

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

Cowles, Christian; Behling, Spencer; Baldez, Phoenix

Here, the feasibility of a full-scale lithium fluoride zinc sulfide (LiF/ZnS) based neutron multiplicity counter has been demonstrated. The counter was constructed of modular neutron detecting stacks that each contain five sheets of LiF/ZnS interleaved between six sheets of wavelength shifting plastic with a photomultiplier tube on each end. Twelve such detector stacks were placed around a sample chamber in a square arrangement with lithiated high-density polyethylene blocks in the corners to reflect high-energy neutrons and capture low-energy neutrons. The final system design was optimized via modeling and small-scale test. Measuring neutrons from a 252Cf source, the counter achieved amore » 36% neutron detection efficiency (ϵϵ) and an View the MathML source11.7μs neutron die-away time (ττ) for a doubles figure-of-merit (ϵ 2/τ) of 109. This is the highest doubles figure-of-merit measured to-date for a 3He-free neutron multiplicity counter.« less

Development of a lithium fluoride zinc sulfide based neutron multiplicity counter

NASA Astrophysics Data System (ADS)

Cowles, Christian; Behling, Spencer; Baldez, Phoenix; Folsom, Micah; Kouzes, Richard; Kukharev, Vladislav; Lintereur, Azaree; Robinson, Sean; Siciliano, Edward; Stave, Sean; Valdez, Patrick

2018-04-01

The feasibility of a full-scale lithium fluoride zinc sulfide (LiF/ZnS) based neutron multiplicity counter has been demonstrated. The counter was constructed of modular neutron detecting stacks that each contain five sheets of LiF/ZnS interleaved between six sheets of wavelength shifting plastic with a photomultiplier tube on each end. Twelve such detector stacks were placed around a sample chamber in a square arrangement with lithiated high-density polyethylene blocks in the corners to reflect high-energy neutrons and capture low-energy neutrons. The final system design was optimized via modeling and small-scale test. Measuring neutrons from a 252Cf source, the counter achieved a 36% neutron detection efficiency (ɛ) and an 11 . 7 μs neutron die-away time (τ) for a doubles figure-of-merit (ɛ2 / τ) of 109. This is the highest doubles figure-of-merit measured to-date for a 3He-free neutron multiplicity counter.

Phenotypic diversification by enhanced genome restructuring after induction of multiple DNA double-strand breaks.

PubMed

Muramoto, Nobuhiko; Oda, Arisa; Tanaka, Hidenori; Nakamura, Takahiro; Kugou, Kazuto; Suda, Kazuki; Kobayashi, Aki; Yoneda, Shiori; Ikeuchi, Akinori; Sugimoto, Hiroki; Kondo, Satoshi; Ohto, Chikara; Shibata, Takehiko; Mitsukawa, Norihiro; Ohta, Kunihiro

2018-05-18

DNA double-strand break (DSB)-mediated genome rearrangements are assumed to provide diverse raw genetic materials enabling accelerated adaptive evolution; however, it remains unclear about the consequences of massive simultaneous DSB formation in cells and their resulting phenotypic impact. Here, we establish an artificial genome-restructuring technology by conditionally introducing multiple genomic DSBs in vivo using a temperature-dependent endonuclease TaqI. Application in yeast and Arabidopsis thaliana generates strains with phenotypes, including improved ethanol production from xylose at higher temperature and increased plant biomass, that are stably inherited to offspring after multiple passages. High-throughput genome resequencing revealed that these strains harbor diverse rearrangements, including copy number variations, translocations in retrotransposons, and direct end-joinings at TaqI-cleavage sites. Furthermore, large-scale rearrangements occur frequently in diploid yeasts (28.1%) and tetraploid plants (46.3%), whereas haploid yeasts and diploid plants undergo minimal rearrangement. This genome-restructuring system (TAQing system) will enable rapid genome breeding and aid genome-evolution studies.

Development of a lithium fluoride zinc sulfide based neutron multiplicity counter

DOE PAGES

Cowles, Christian; Behling, Spencer; Baldez, Phoenix; ...

2018-01-12

Here, the feasibility of a full-scale lithium fluoride zinc sulfide (LiF/ZnS) based neutron multiplicity counter has been demonstrated. The counter was constructed of modular neutron detecting stacks that each contain five sheets of LiF/ZnS interleaved between six sheets of wavelength shifting plastic with a photomultiplier tube on each end. Twelve such detector stacks were placed around a sample chamber in a square arrangement with lithiated high-density polyethylene blocks in the corners to reflect high-energy neutrons and capture low-energy neutrons. The final system design was optimized via modeling and small-scale test. Measuring neutrons from a 252Cf source, the counter achieved amore » 36% neutron detection efficiency (ϵϵ) and an View the MathML source11.7μs neutron die-away time (ττ) for a doubles figure-of-merit (ϵ 2/τ) of 109. This is the highest doubles figure-of-merit measured to-date for a 3He-free neutron multiplicity counter.« less

Analysis of multiple internal reflections in a parallel aligned liquid crystal on silicon SLM.

PubMed

Martínez, José Luis; Moreno, Ignacio; del Mar Sánchez-López, María; Vargas, Asticio; García-Martínez, Pascuala

2014-10-20

Multiple internal reflection effects on the optical modulation of a commercial reflective parallel-aligned liquid-crystal on silicon (PAL-LCoS) spatial light modulator (SLM) are analyzed. The display is illuminated with different wavelengths and different angles of incidence. Non-negligible Fabry-Perot (FP) effect is observed due to the sandwiched LC layer structure. A simplified physical model that quantitatively accounts for the observed phenomena is proposed. It is shown how the expected pure phase modulation response is substantially modified in the following aspects: 1) a coupled amplitude modulation, 2) a non-linear behavior of the phase modulation, 3) some amount of unmodulated light, and 4) a reduction of the effective phase modulation as the angle of incidence increases. Finally, it is shown that multiple reflections can be useful since the effect of a displayed diffraction grating is doubled on a beam that is reflected twice through the LC layer, thus rendering gratings with doubled phase modulation depth.

Student Measurements of STFA 14 AC at Vanguard Preparatory School

NASA Astrophysics Data System (ADS)

Gillette, Sean; Archuleta, Alex; Diaz, Lizbeth; Gillespie, Kyle; Gosney, Timothy; Johnson, Stephen; Mohan, Nikita; Rajacich, Jacob; Roehl, Nathaniel; Sharpe, Scotty; Whitt, Kahaloha

2016-01-01

Eighth grade students at Vanguard Preparatory School measured the double star STFA 14 AC using a Bader Planetarium Micro Guide eyepiece. Navi (Gamma Cassiopeiae) was used as the ca libration star. The calculated means of multiple observations of STFA 14 AC resulted in a separation of 53.3" and a position angle of 2.0°. These measurements were compared to the most recent values in the Washington Double Star Catalog.

Analysis of the Functionality of Refillable Propellant Management Devices (PMD)

NASA Astrophysics Data System (ADS)

Winkelmann, Yvonne; Gaulke, Diana; Dreyer, Michael E.

In order to restart a stage of a spacecraft it is necessary to position the liquid stable over the tank outlet. The gas-or vapor-free provision of the thrusters for the main engine start-up can be accomplished by the use of propellant management devices (PMDs). A propellant refillable reservoir (PRR) will supply the engine with the required amount of liquid propellant until the liquid outside the PRR has settled at the bottom of the tank. Hence, the reservoir will be refilled and the main engine can be restarted. This technique has been applied in case of storable propellants yet, e.g. in satellites or ATVs. For the application in a cryogenic upper stage demonstration and validation tests are still necessary. Ground experiments to simulate propulsed phases are evaluated. To demonstrate the functionality under propulsed conditions first filling, draining and draining with a constant fill level of the tank (refilling) are analyzed. Different inflows with respect to filling and varied outflow rates for the draining tests are investigated. Pressure losses in the LOX-PMD are measured during draining and compared to a previously accomplished estimation with an one-dimensional streamtube theory.

Multifocal Neuropathy: Expanding the Scope of Double Crush Syndrome.

PubMed

Cohen, Brian H; Gaspar, Michael P; Daniels, Alan H; Akelman, Edward; Kane, Patrick M

2016-12-01

Double crush syndrome (DCS), as it is classically defined, is a clinical condition composed of neurological dysfunction due to compressive pathology at multiple sites along a single peripheral nerve. The traditional definition of DCS is narrow in scope because many systemic pathologic processes, such as diabetes mellitus, drug-induced neuropathy, vascular disease and autoimmune neuronal damage, can have deleterious effects on nerve function. Multifocal neuropathy is a more appropriate term describing the multiple etiologies (including compressive lesions) that may synergistically contribute to nerve dysfunction and clinical symptoms. This paper examines the history of DCS and multifocal neuropathy, including the epidemiology and pathophysiology in addition to principles of evaluation and management. Copyright © 2016 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Classical Observations of Visual Binary and Multiple Stars

NASA Astrophysics Data System (ADS)

Mason, Brian D.

2007-08-01

The database of visual double star data has experienced tremendous changes, doubling in size during the last 25 years and growing at an ever increasing rate. Interferometric techniques have allowed the database to extend to much closer separation (and shorter periods), while longer timebases and higher-precision wide-field surveys have increased our knowledge of common proper motion pairs at the widest separations. These changes in the database are highlighted, describing the evolution of methods of observation (both historically and the past few years) and the effectiveness of these various methods in different regimes of separation/ period space. The various niches for wide- and narrow-field work as applied to double and multiple stars are examined and the different types of information which each can provide are also highlighted. After more than 20 years of successful work, speckle interferometry and conventional CCD astrometry have replaced filar micrometry and photography as the preferred classical techniques. Indeed, most work in filar micrometry is now being done by amateurs, although much of that community is also switching to CCDs and other electronic techniques. Despite the significant growth of the double star database, much still remains to be done, such as finding lost pairs, filling in missing parameters so that observing programs may be more efficient at observing stars appropriate to their capabilities, and providing at least approximate kinematic descriptions. Work on pairs described as neglected at the time of the last major WDS data release (2001) is given as a specific example of recent improvements, and finally the continued need to publish data using classical double star parameters is discussed.

Development and Application of a Two-Tier Multiple Choice Diagnostic Instrument To Assess High School Students' Understanding of Inorganic Chemistry Qualitative Analysis.

ERIC Educational Resources Information Center

Tan, Kim Chwee Daniel; Goh, Ngoh Khang; Chia, Lian Sai; Treagust, David F.

2002-01-01

Describes the development and application of a two-tier multiple choice diagnostic instrument to assess high school students' understanding of inorganic chemistry qualitative analysis. Shows that the Grade 10 students had difficulty understanding the reactions involved in the identification of cations and anions, for example, double decomposition…

Efficacy of a multi micronutrient-fortified drink in improving iron and micronutrient status among schoolchildren with low iron stores in India: A randomised, double-masked placebo-controlled trial

USDA-ARS?s Scientific Manuscript database

A multiple micronutrient-fortified drink could be an effective strategy to combating micronutrient deficiencies in school-going children. Our objective was to assess the efficacy of a multiple micronutrient-fortified drink in reducing iron deficiency (ID), ID anemia (IDA), anemia and improving micro...

Deciphering the associations between gene expression and copy number alteration using a sparse double Laplacian shrinkage approach

PubMed Central

Shi, Xingjie; Zhao, Qing; Huang, Jian; Xie, Yang; Ma, Shuangge

2015-01-01

Motivation: Both gene expression levels (GEs) and copy number alterations (CNAs) have important biological implications. GEs are partly regulated by CNAs, and much effort has been devoted to understanding their relations. The regulation analysis is challenging with one gene expression possibly regulated by multiple CNAs and one CNA potentially regulating the expressions of multiple genes. The correlations among GEs and among CNAs make the analysis even more complicated. The existing methods have limitations and cannot comprehensively describe the regulation. Results: A sparse double Laplacian shrinkage method is developed. It jointly models the effects of multiple CNAs on multiple GEs. Penalization is adopted to achieve sparsity and identify the regulation relationships. Network adjacency is computed to describe the interconnections among GEs and among CNAs. Two Laplacian shrinkage penalties are imposed to accommodate the network adjacency measures. Simulation shows that the proposed method outperforms the competing alternatives with more accurate marker identification. The Cancer Genome Atlas data are analysed to further demonstrate advantages of the proposed method. Availability and implementation: R code is available at http://works.bepress.com/shuangge/49/ Contact: shuangge.ma@yale.edu Supplementary information: Supplementary data are available at Bioinformatics online. PMID:26342102

Concept of multiple-cell cavity for axion dark matter search

NASA Astrophysics Data System (ADS)

Jeong, Junu; Youn, SungWoo; Ahn, Saebyeok; Kim, Jihn E.; Semertzidis, Yannis K.

2018-02-01

In cavity-based axion dark matter search experiments exploring high mass regions, multiple-cavity design is under consideration as a method to increase the detection volume within a given magnet bore. We introduce a new idea, referred to as a multiple-cell cavity, which provides various benefits including a larger detection volume, simpler experimental setup, and easier phase-matching mechanism. We present the characteristics of this concept and demonstrate the experimental feasibility with an example of a double-cell cavity.

[DNA structure from A to Z--biological implications of structural diversity of DNA].

PubMed

Bukowiecka-Matusiak, Małgorzata; Woźniak, Lucyna A

2006-01-01

Deoxyribonucleic acid (DNA) is a biopolymer of nucleotides, usually adopting a double-stranded helical form in cells, with complementary base pairing holding the two strands together. The most stable is B-DNA conformation, although numerous other double helical structures can occur under specific conditions (A-DNA, Z-DNA, P-DNA). The existence of multiple-stranded (triplex, tetraplex) forms in vivo and their biological function in cells are subject of intensive studies.

A Van der Waals-like theory of plasma double layers

NASA Technical Reports Server (NTRS)

Katz, Ira; Davis, V. A.

1989-01-01

A theory describing plasma double layers in terms of multiple roots of the charge density expression is presented. The theory presented uses the fact that equilibrium plasmas shield small potential perturbations linearly; for high potentials, the shielding decreases. The approach is analogous to Van der Waals' theory of simple fluids in which inclusion of approximate expressions for both excluded volume and long range attractive forces sufficiently describes the first-order liquid-gas phase transition.

Numerically simulated two-dimensional auroral double layers

NASA Technical Reports Server (NTRS)

Borovsky, J. E.; Joyce, G.

1983-01-01

A magnetized 2 1/2-dimensional particle-in-cell system which is periodic in one direction and bounded by reservoirs of Maxwellian plasma in the other is used to numerically simulate electrostatic plasma double layers. For the cases of both oblique and two-dimensional double layers, the present results indicate periodic instability, Debye length rather than gyroradii scaling, and low frequency electrostatic turbulence together with electron beam-excited electrostatatic electron-cyclotron waves. Estimates are given for the thickness of auroral doule layers, as well as the separations within multiple auroral arcs. Attention is given to the temporal modulation of accelerated beams, and the possibilities for ion precipitation and ion conic production by the double layer are hypothesized. Simulations which include the atmospheric backscattering of electrons imply the action of an ionospheric sheath which accelerates ionospheric ions upward.

Double Ramification Cycles and Quantum Integrable Systems

NASA Astrophysics Data System (ADS)

Buryak, Alexandr; Rossi, Paolo

2016-03-01

In this paper, we define a quantization of the Double Ramification Hierarchies of Buryak (Commun Math Phys 336:1085-1107, 2015) and Buryak and Rossi (Commun Math Phys, 2014), using intersection numbers of the double ramification cycle, the full Chern class of the Hodge bundle and psi-classes with a given cohomological field theory. We provide effective recursion formulae which determine the full quantum hierarchy starting from just one Hamiltonian, the one associated with the first descendant of the unit of the cohomological field theory only. We study various examples which provide, in very explicit form, new (1+1)-dimensional integrable quantum field theories whose classical limits are well-known integrable hierarchies such as KdV, Intermediate Long Wave, extended Toda, etc. Finally, we prove polynomiality in the ramification multiplicities of the integral of any tautological class over the double ramification cycle.

Arabidopsis thaliana gonidialess A/Zuotin related factors (GlsA/ZRF) are essential for maintenance of meristem integrity.

PubMed

Guzmán-López, José Alfredo; Abraham-Juárez, María Jazmín; Lozano-Sotomayor, Paulina; de Folter, Stefan; Simpson, June

2016-05-01

Observation of a differential expression pattern, including strong expression in meristematic tissue of an Agave tequilana GlsA/ZRF ortholog suggested an important role for this gene during bulbil formation and developmental changes in this species. In order to better understand this role, the two GlsA/ZFR orthologs present in the genome of Arabidopsis thaliana were functionally characterized by analyzing expression patterns, double mutant phenotypes, promoter-GUS fusions and expression of hormone related or meristem marker genes. Patterns of expression for A. thaliana show that GlsA/ZFR genes are strongly expressed in SAMs and RAMs in mature plants and developing embryos and double mutants showed multiple changes in morphology related to both SAM and RAM tissues. Typical double mutants showed stunted growth of aerial and root tissue, formation of multiple ectopic meristems and effects on cotyledons, leaves and flowers. The KNOX genes STM and BP were overexpressed in double mutants whereas CLV3, WUSCHEL and AS1 were repressed and lack of AtGlsA expression was also associated with changes in localization of auxin and cytokinin. These results suggest that GlsA/ZFR is an essential component of the machinery that maintains the integrity of SAM and RAM tissue and underline the potential to identify new genes or gene functions based on observations in non-model plants.

Multiple homicides.

PubMed

Copeland, A R

1989-09-01

A study of multiple homicides or multiple deaths involving a solitary incident of violence by another individual was performed on the case files of the Office of the Medical Examiner of Metropolitan Dade County in Miami, Florida, during 1983-1987. A total of 107 multiple homicides were studied: 88 double, 17 triple, one quadruple, and one quintuple. The 236 victims were analyzed regarding age, race, sex, cause of death, toxicologic data, perpetrator, locale of the incident, and reason for the incident. This article compares this type of slaying with other types of homicide including those perpetrated by serial killers. Suggestions for future research in this field are offered.

Excitation of the Earth's Chandler wobble by a turbulent oceanic double-gyre

NASA Astrophysics Data System (ADS)

Naghibi, S. E.; Jalali, M. A.; Karabasov, S. A.; Alam, M.-R.

2017-04-01

We develop a layer-averaged, multiple-scale spectral ocean model and show how an oceanic double-gyre can communicate with the Earth's Chandler wobble. The overall transfers of energy and angular momentum from the double-gyre to the Chandler wobble are used to calibrate the turbulence parameters of the layer-averaged model. Our model is tested against a multilayer quasi-geostrophic ocean model in turbulent regime, and base states used in parameter identification are obtained from mesoscale eddy resolving numerical simulations. The Chandler wobble excitation function obtained from the model predicts a small role of North Atlantic ocean region on the wobble dynamics as compared to all oceans, in agreement with the existing observations.

Atomic Resolution in Situ Imaging of a Double-Bilayer Multistep Growth Mode in Gallium Nitride Nanowires

DOE PAGES

Gamalski, A. D.; Tersoff, J.; Stach, E. A.

2016-04-13

We study the growth of GaN nanowires from liquid Au–Ga catalysts using environmental transmission electron microscopy. GaN wires grow in either (11¯20) or (11¯00) directions, by the addition of {11¯00} double bilayers via step flow with multiple steps. Step-train growth is not typically seen with liquid catalysts, and we suggest that it results from low step mobility related to the unusual double-height step structure. Finally, the results here illustrate the surprising dynamics of catalytic GaN wire growth at the nanoscale and highlight striking differences between the growth of GaN and other III–V semiconductor nanowires.

Practice and attitudes regarding double gloving among staff surgeons and surgical trainees.

PubMed

Lipson, Mark E; Deardon, Rob; Switzer, Noah J; de Gara, Chris; Ball, Chad G; Grondin, Sean C

2018-06-01

Despite supporting evidence, many staff surgeons and surgical trainees do not routinely double glove. We performed a study to assess rates of and attitudes toward double gloving and the use of eye protection in the operating room. We conducted an electronic survey among all staff surgeons and surgical trainees at 2 tertiary care centres in Alberta between September and November 2015.We analyzed the data using log-binomial regression for binary outcomes to account for multiple independent variables and interactions. For 2-group comparisons, we used a 2-group test of proportions. The response rate was 34.3% (361/1051); 205/698 staff surgeons (29.4%) and 156/353 surgical trainees (44.2%) responded. Trainees were more likely than staff surgeons to ever double glove in the operating room ( p = 0.01) and to do so routinely ( p = 0.01). Staff surgeons were more likely than trainees to never double glove ( p = 0.01). A total of 300/353 respondents (85.0%) reported using eye protection routinely in the operating room. Needle-stick injury was common (184 staff surgeons [92.5%], 115 trainees [74.7%]). Reduced tactile feedback, decreased manual dexterity and discomfort/poor fit were perceived barriers to double gloving. Rates of double gloving leave room for improvement. Surgical trainees were more likely than staff surgeons to double glove. Barriers remain to routine double gloving among staff surgeons and trainees. Increased education on the benefits of double gloving and early introduction of this practice may increase uptake.

Advanced analysis techniques for uranium assay

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

Geist, W. H.; Ensslin, Norbert; Carrillo, L. A.

2001-01-01

Uranium has a negligible passive neutron emission rate making its assay practicable only with an active interrogation method. The active interrogation uses external neutron sources to induce fission events in the uranium in order to determine the mass. This technique requires careful calibration with standards that are representative of the items to be assayed. The samples to be measured are not always well represented by the available standards which often leads to large biases. A technique of active multiplicity counting is being developed to reduce some of these assay difficulties. Active multiplicity counting uses the measured doubles and triples countmore » rates to determine the neutron multiplication (f4) and the product of the source-sample coupling ( C ) and the 235U mass (m). Since the 35U mass always appears in the multiplicity equations as the product of Cm, the coupling needs to be determined before the mass can be known. A relationship has been developed that relates the coupling to the neutron multiplication. The relationship is based on both an analytical derivation and also on empirical observations. To determine a scaling constant present in this relationship, known standards must be used. Evaluation of experimental data revealed an improvement over the traditional calibration curve analysis method of fitting the doubles count rate to the 235Um ass. Active multiplicity assay appears to relax the requirement that the calibration standards and unknown items have the same chemical form and geometry.« less

Future Performance Trend Indicators: A Current Value Approach to Human Resources Accounting. Report III. Multivariate Predictions of Organizational Performance Across Time.

ERIC Educational Resources Information Center

Pecorella, Patricia A.; Bowers, David G.

Multiple regression in a double cross-validated design was used to predict two performance measures (total variable expense and absence rate) by multi-month period in five industrial firms. The regressions do cross-validate, and produce multiple coefficients which display both concurrent and predictive effects, peaking 18 months to two years…

Recent advances in heterobimetallic palladium(II)/copper(II) catalyzed domino difunctionalization of carbon-carbon multiple bonds.

PubMed

Beccalli, Egle M; Broggini, Gianluigi; Gazzola, Silvia; Mazza, Alberto

2014-09-21

The double functionalization of carbon-carbon multiple bonds in one-pot processes has emerged in recent years as a fruitful tool for the rapid synthesis of complex molecular scaffolds. This review covers the advances in domino reactions promoted by the couple palladium(ii)/copper(ii), which was proven to be an excellent catalytic system for the functionalization of substrates.

Going Green and Using Less Paper to Print Exams: Student Performance, Completion Time, and Preference

ERIC Educational Resources Information Center

O'Connor, Kevin J.

2014-01-01

Two studies measured the impact on student exam performance and exam completion time of strategies aimed to reduce the amount of paper used for printing multiple-choice course exams. Study 1 compared single-sided to double-sided printed exams. Study 2 compared a single-column arrangement of multiple-choice answer options to a space (and paper)…

Spatial redistribution of radiation in flip-chip photodiodes based on InAsSbP/InAs double heterostructures

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

Zakgeim, A. L.; Il’inskaya, N. D.; Karandashev, S. A.

2017-02-15

The spatial distribution of equilibrium and nonequilibrium (including luminescent) IR (infrared) radiation in flip-chip photodiodes based on InAsSbP/InAs double heterostructures (λ{sub max} = 3.4 μm) is measured and analyzed; the structural features of the photodiodes, including the reflective properties of the ohmic contacts, are taken into account. Optical area enhancement due to multiple internal reflection in photodiodes with different geometric characteristics is estimated.

Student Measurements of STFA 10AB (Theta Tauri)

NASA Astrophysics Data System (ADS)

Gillette, Sean; Estrada, Chris; Estrada, Reed; Aguilera, Sophia; Chavez, Valerie; Givens, Jalynn; Lindorfer, Sarah; Michels, Kaylie; Mobley, Makenzie; Reder, Gabriel; Renteria, Kayla; Shattles, Jenna; Wilkin, Aiden; Woodbury, Maisy; Rhoades, Breauna; Rhoades, Mark

2017-04-01

Eighth grade students at Vanguard Preparatory School measured the double star STFA 10AB using a 22-inch Newtonian Alt/Az telescope and a Celestron Micro Guide eyepiece. Bellatrix was used as the calibration star. The calculated means of multiple observations of STFA 10AB resulted in a separation of 45.18,” a scale constant of 7.88 arcseconds per division, and position angle of 257.9°. These measurements were compared to the most recent values in the Washington Double Star Catalog.

Laser Speckle Photography: Some Simple Experiments for the Undergraduate Laboratory.

ERIC Educational Resources Information Center

Bates, B.; And Others

1986-01-01

Describes simple speckle photography experiments which are easy to set up and require only low cost standard laboratory equipment. Included are procedures for taking single, double, and multiple exposures. (JN)

Analyses of the radiation of birnaviruses from diverse host phyla and of their evolutionary affinities with other double-stranded RNA and positive strand RNA viruses using robust structure-based multiple sequence alignments and advanced phylogenetic methods

PubMed Central

2013-01-01

Background Birnaviruses form a distinct family of double-stranded RNA viruses infecting animals as different as vertebrates, mollusks, insects and rotifers. With such a wide host range, they constitute a good model for studying the adaptation to the host. Additionally, several lines of evidence link birnaviruses to positive strand RNA viruses and suggest that phylogenetic analyses may provide clues about transition. Results We characterized the genome of a birnavirus from the rotifer Branchionus plicalitis. We used X-ray structures of RNA-dependent RNA polymerases and capsid proteins to obtain multiple structure alignments that allowed us to obtain reliable multiple sequence alignments and we employed “advanced” phylogenetic methods to study the evolutionary relationships between some positive strand and double-stranded RNA viruses. We showed that the rotifer birnavirus genome exhibited an organization remarkably similar to other birnaviruses. As this host was phylogenetically very distant from the other known species targeted by birnaviruses, we revisited the evolutionary pathways within the Birnaviridae family using phylogenetic reconstruction methods. We also applied a number of phylogenetic approaches based on structurally conserved domains/regions of the capsid and RNA-dependent RNA polymerase proteins to study the evolutionary relationships between birnaviruses, other double-stranded RNA viruses and positive strand RNA viruses. Conclusions We show that there is a good correlation between the phylogeny of the birnaviruses and that of their hosts at the phylum level using the RNA-dependent RNA polymerase (genomic segment B) on the one hand and a concatenation of the capsid protein, protease and ribonucleoprotein (genomic segment A) on the other hand. This correlation tends to vanish within phyla. The use of advanced phylogenetic methods and robust structure-based multiple sequence alignments allowed us to obtain a more accurate picture (in terms of probability of the tree topologies) of the evolutionary affinities between double-stranded RNA and positive strand RNA viruses. In particular, we were able to show that there exists a good statistical support for the claims that dsRNA viruses are not monophyletic and that viruses with permuted RdRps belong to a common evolution lineage as previously proposed by other groups. We also propose a tree topology with a good statistical support describing the evolutionary relationships between the Picornaviridae, Caliciviridae, Flaviviridae families and a group including the Alphatetraviridae, Nodaviridae, Permutotretraviridae, Birnaviridae, and Cystoviridae families. PMID:23865988

Stolen twin: fascination and curiosity/twin research reports: evolution of sleep length; dental treatment of craniopagus twins; cryopreserved double embryo transfer; gender options in multiple pregnancy/current events: appendectomy in one twin; autistic twin marathon runners; 3D facial recognition; twin biathletes.

PubMed

Segal, Nancy L

2014-02-01

The story of her allegedly stolen twin brother in Armenia is recounted by a 'singleton twin' living in the United States. The behavioral consequences and societal implications of this loss are considered. This case is followed by twin research reports on the evolution of sleep length, dental treatment of craniopagus conjoined twins, cryopreserved double embryo transfer (DET), and gender options in multiple pregnancy. Current events include the diagnosis of appendectomy in one identical twin, the accomplishments of autistic twin marathon runners, the power of three-dimensional (3D) facial recognition, and the goals of twin biathletes heading to the 2014 Sochi Olympics in Russia.

Soft pair excitations and double-log divergences due to carrier interactions in graphene

NASA Astrophysics Data System (ADS)

Lewandowski, Cyprian; Levitov, L. S.

2018-03-01

Interactions between charge carriers in graphene lead to logarithmic renormalization of observables mimicking the behavior known in (3+1)-dimensional quantum electrodynamics (QED). Here we analyze soft electron-hole (e -h ) excitations generated as a result of fast charge dynamics, a direct analog of the signature QED effect—multiple soft photons produced by the QED vacuum shakeup. We show that such excitations are generated in photon absorption, when a photogenerated high-energy e -h pair cascades down in energy and gives rise to multiple soft e -h excitations. This fundamental process is manifested in a double-log divergence in the emission rate of soft pairs and a characteristic power-law divergence in their energy spectrum of the form 1/ω ln(ω/Δ ) . Strong carrier-carrier interactions make pair production a prominent pathway in the photoexcitation cascade.

Analysis of Vibrational Harmonic Response for Printing Double-Sheet Detecting System via ANSYS

NASA Astrophysics Data System (ADS)

Guo, Qiang; Cai, Ji-Fei; Wang, Yan; Zhang, Yang

In order to explore the influence of the harmonic response of system vibration upon the stability of the double-sheet detector system, the mathematical model of vibrational system is established via the mechanical dynamic theory. Vibrational system of double-sheet detector is studied by theoretical modeling, and the dynamic simulation to obtain the amplitude/phase frequency response curve of the system based on ANSYS is completed to make a comparison with the theoretical results. It is shown that the theoretical value is basically consistent with that calculated through ANSYS. Conclusion vibrational characteristics of double-sheet detection system is obtained quickly and accurately, and propound solving measures by some crucial factors, such as the harmonic load, mass and stiffness, which will affect the vibration of the system, contribute to the finite element method is applied to the complex multiple-degree-of-freedom system.

Solar system applications of Mie theory and of radiative transfer of polarized light

NASA Technical Reports Server (NTRS)

Whitehill, L. P.

1972-01-01

A theory of the multiple scattering of polarized light is discussed using the doubling method of van de Hulst. The concept of the Stokes parameters is derived and used to develop the form of the scattering phase matrix of a single particle. The diffuse reflection and transmission matrices of a single scattering plane parallel atmosphere are expressed as a function of the phase matrix, and the symmetry properties of these matrices are examined. Four matrices are required to describe scattering and transmission. The scattering matrix that results from the addition of two identical layers is derived. Using the doubling method, the scattering and transmission matrices of layers of arbitrary optical thickness can be derived. The doubling equations are then rewritten in terms of their Fourier components. Computation time is reduced since each Fourier component doubles independently. Computation time is also reduced through the use of symmetry properties.

VizieR Online Data Catalog: Photometry of multiple stars at NAOR&ASV in 2015 (Cvetkovic+, 2017)

NASA Astrophysics Data System (ADS)

Cvetkovic, Z.; Pavlovic, R.; Boeva, S.

2018-05-01

This is the ninth series of CCD observations of double and multiple stars, obtained at the Bulgarian National Astronomical Observatory at Rozhen (NAOR) over five nights. As previously, the CCD camera VersArray 1300B was used, which was attached to the 2 m telescope. For each double or multiple star, five CCD frames in the Johnson B filter and five frames in the Johnson V filter were taken, which enabled us to determine the magnitude difference for these filters. In 2015 at the Astronomical Station at Vidojevica (ASV), over a total of 23 nights, observations were carried out by using the 60 cm telescope with a Cassegrain optical system. This is the fourth observational series at ASV since the work started there in 2011. In the observations we used the Apogee Alta U42 CCD camera whose characteristics can be found in the paper by Cvetkovic et al. (2016, J/AJ/151/58). Every pair was observed five times in the Cousins/Bessel B filter and five times in the Cousins/Bessel V one. (3 data files).

Scene of Multiple Explosions

NASA Image and Video Library

2007-03-07

This composite image NASA Galaxy Evolution Explorer shows Z Camelopardalis, or Z Cam, a double-star system featuring a collapsed, dead star, called a white dwarf, and a companion star, as well as a ghostly shell around the system.

Controlled double emulsification utilizing 3D PDMS microchannels

NASA Astrophysics Data System (ADS)

Chang, Fu-Che; Su, Yu-Chuan

2008-06-01

This paper presents a PDMS emulsification device that is capable of generating water-in-oil-in-water double emulsions in a controlled manner. Specially designed 3D microchannels are utilized to steer the independently driven water- and oil-phase flows (especially to restrict the attachment of the middle oil-phase flow on the channel surfaces), and to break the continuous flows into monodisperse double emulsions. In addition to channel geometries and fluid flow rates, surfactants and osmotic agents are employed to facilitate the breakup process and stabilize the resulting emulsion structures. In the prototype demonstration, two-level SU-8 molds were fabricated to duplicate PDMS microstructures, which were surface treated and bonded irreversibly to form 3D microchannels. Throughout the emulsification trials, dripping was intentionally induced to generate monodisperse double emulsions with single or multiple aqueous droplets inside each oil drop. It is found that the overall and core sizes of the resulting double emulsions could be adjusted independently, mainly by varying the outer and inner fluid flow rates, respectively. As such, the presented double emulsification device could potentially realize the controllability on emulsion structure and size distribution, which is desired for a variety of biological and pharmaceutical applications.

Double versus single high-dose melphalan 200 mg/m2 and autologous stem cell transplantation for multiple myeloma: a region-based study in 484 patients from the Nordic area

PubMed Central

Björkstrand, Bo; Klausen, Tobias W.; Remes, Kari; Gruber, Astrid; Knudsen, Lene M.; Bergmann, Olav J.; Lenhoff, Stig; Johnsen, Hans E.

2009-01-01

Autologous stem cell transplantation is still considered the standard of care in young patients with multiple myeloma (MM). This disease is the most common indication for high-dose therapy (HDT) supported by hematopoietic stem cell transplantation and much data support the benefit of this procedure. Results of randomized studies are in favor of tandem autologous transplantation although the effect on overall survival is unclear. Based on sequential registration trials in the Nordic area, we aimed to evaluate the outcome of conventional single or double HDT. During 1994–2000 we registered a total of 484 previously untreated patients under the age of 60 years at diagnosis who on a regional basis initially were treated with single [Trial NMSG #5/94 and #7/98 (N=383)] or double [Trial Huddinge Karolinska Turku Herlev (N=101)] high-dose melphalan (200 mg/m2) therapy supported by autologous stem cell transplantation. A complete or very good partial response was achieved by 40% of patients in the single transplant group and 60% of patients in the double transplant group (p=0.0006). The probability of surviving progression free for five years after the diagnosis was 25% (95% CL 18–32%) in the singletransplant group and 46% (95% CL 33–55%) in the double transplant group (p=0.0014). The estimated overall five-year survival rate was 60% in the single transplant group and 64% in the doubletransplant (p=0.9). In a multivariate analysis of variables, including single versus double transplantation, β2 microglobulin level, age, sex and disease stage, only β2 microglobulin level was predictive for overall survival (p>0.0001) and progression free survival (p=0.001). In accordance with these results, a 1:1 case-control matched comparison between double and single transplantation did not identify significant differences in overall and progression free survival. In this retrospective analysis up front double transplantation with melphalan (200 mg/m2) as compared to single transplantation did not seem to improve the final outcome among patients in the Nordic area. These data are in accordance with recent publications from the Bologna 96 trial indicating that a second transplant should not be recommended up front as standard care.

Multifunctional Metallosupramolecular Materials

DTIC Science & Technology

2011-02-28

supramolecular polymers based on 16 and Zn(NTf2)2 using small- angle X - ray scattering (SAXS) and transmission electron microscopy (TEM), carried out by...The SAXS data (Figure 13a) show multiple strong Bragg diffraction maxima at integer multiples of the scattering vector of the primary diffraction ...a minor amount of residual double bonds in the poly(ethylene-co-butylene) core. The metallopolymers 16·[Zn(NTf2)2] x exhibit similar traces, but do

Task-dependent response conflict monitoring and cognitive control in anterior cingulate and dorsolateral prefrontal cortices.

PubMed

Kim, Chobok; Chung, Chongwook; Kim, Jeounghoon

2013-11-06

Previous experience affects our behavior in terms of adjustments. It has been suggested that the conflict monitor-controller system implemented in the prefrontal cortex plays a critical role in such adjustments. Previous studies suggested that there exists multiple conflict monitor-controller systems associated with the level of information (i.e., stimulus and response levels). In this study, we sought to test whether different types of conflicts occur at the same information processing level (i.e., response level) are independently processed. For this purpose, we designed a task paradigm to measure two different types of response conflicts using color-based and location-based conflict stimuli and measured the conflict adaptation effects associated with the two types of conflicts either independently (i.e., single conflict conditions) or simultaneously (i.e., a double-conflict condition). The behavioral results demonstrated that performance on current incongruent trials was faster only when the preceding trial was the same type of response conflict regardless of whether they included a single- or double-conflict. Imaging data also showed that anterior cingulate and dorsolateral prefrontal cortices operate in a task-specific manner. These findings suggest that there may be multiple monitor-controller loops for color-based and location-based conflicts even at the same response level. Importantly, our results suggest that double-conflict processing is qualitatively different from single-conflict processing although double-conflict shares the same sources of conflict with two single-conflict conditions. © 2013 Published by Elsevier B.V.

Interferon-alpha and transfer factor in the treatment of multiple sclerosis: a double-blind, placebo-controlled trial. AUSTIMS Research Group.

PubMed Central

1989-01-01

The role of interferon-alpha (IFN-alpha) and transfer factor (TF) in the treatment of multiple sclerosis was investigated in a prospective, multi-centric, three year, double-blind, placebo-controlled trial. One hundred and eighty two patients with clinically definite multiple sclerosis were randomised into three treatment groups whose compositions were found to be similar for demographic and prognostic variables including HLA status. Subcutaneous injections of IFN-alpha (3 x 10(6) units), TF (0.5 units) manufactured from leucocytes of cohabiting donors, or placebo were given twice weekly for two months, once weekly for 10 months then fortnightly for 24 months. One hundred and fifty three patients completed the injection regimen. There was no significant difference in the progression of disability for multiple sclerosis patients in either the IFN-alpha or TF-treated groups compared with the placebo group. Similarly, change in visual evoked responses (VER), and in number of oligoclonal bands (OCB) and the level of myelin basic protein (MBP) in the cerebrospinal fluid (CSF) over the trial period did not differ significantly between the three groups. However, the IFN-alpha-treated group had significantly more reported adverse drug reactions and patient withdrawals than either of the other two groups. PMID:2659737

Multiple nonlinear Bragg diffraction of femtosecond laser pulses in a {\\chi^{(2)}} photonic lattice with hexagonal domains

NASA Astrophysics Data System (ADS)

Vyunishev, A. M.; Arkhipkin, V. G.; Baturin, I. S.; Akhmatkhanov, A. R.; Shur, V. Ya; Chirkin, A. S.

2018-04-01

The frequency doubling of femtosecond laser pulses in a two-dimensional (2D) rectangular nonlinear photonic lattice with hexagonal domains is studied experimentally and theoretically. The broad fundamental spectrum enables frequency conversion under nonlinear Bragg diffraction for a series of transverse orders at a fixed longitudinal quasi-phase-matching order. The consistent nonstationary theory of the frequency doubling of femtosecond laser pulses is developed using the representation based on the reciprocal lattice of the structure. The calculated spatial distribution of the second-harmonic spectral intensity agrees well with the experimental data. The condition for multiple nonlinear Bragg diffraction in a 2D nonlinear photonic lattice is offered. The hexagonal shape of the domains contributes to multibeam second harmonic excitation. The maximum conversion efficiency for a series of transverse orders in the range 0.01%-0.03% is obtained.

Low Noise Double-Sided Silicon Strip Detector for Multiple-Compton Gamma-ray Telescope

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

Tajima, Hiroyasu

2002-12-03

A Semiconductor Multiple-Compton Telescope (SMCT) is being developed to explore the gamma-ray universe in an energy band 0.1-20 MeV, which is not well covered by the present or near-future gamma-ray telescopes. The key feature of the SMCT is the high energy resolution that is crucial for high angular resolution and high background rejection capability. We have developed prototype modules for a low noise Double-sided Silicon Strip Detector (DSSD) system which is an essential element of the SMCT. The geometry of the DSSD is optimized to achieve the lowest noise possible. A new front-end VLSI device optimized for low noise operationmore » is also developed. We report on the design and test results of the prototype system. We have reached an energy resolution of 1.3 keV (FWHM) for 60 keV and 122 keV at 0 C.« less

Signal Processing for Wireless Communication MIMO System with Nano- Scaled CSDG MOSFET based DP4T RF Switch.

PubMed

Srivastava, Viranjay M

2015-01-01

In the present technological expansion, the radio frequency integrated circuits in the wireless communication technologies became useful because of the replacement of increasing number of functions, traditional hardware components by modern digital signal processing. The carrier frequencies used for communication systems, now a day, shifted toward the microwave regime. The signal processing for the multiple inputs multiple output wireless communication system using the Metal- Oxide-Semiconductor Field-Effect-Transistor (MOSFET) has been done a lot. In this research the signal processing with help of nano-scaled Cylindrical Surrounding Double Gate (CSDG) MOSFET by means of Double- Pole Four-Throw Radio-Frequency (DP4T RF) switch, in terms of Insertion loss, Isolation, Reverse isolation and Inter modulation have been analyzed. In addition to this a channel model has been presented. Here, we also discussed some patents relevant to the topic.

Strong correlation in incremental full configuration interaction

NASA Astrophysics Data System (ADS)

Zimmerman, Paul M.

2017-06-01

Incremental Full Configuration Interaction (iFCI) reaches high accuracy electronic energies via a many-body expansion of the correlation energy. In this work, the Perfect Pairing (PP) ansatz replaces the Hartree-Fock reference of the original iFCI method. This substitution captures a large amount of correlation at zero-order, which allows iFCI to recover the remaining correlation energy with low-order increments. The resulting approach, PP-iFCI, is size consistent, size extensive, and systematically improvable with increasing order of incremental expansion. Tests on multiple single bond, multiple double bond, and triple bond dissociations of main group polyatomics using double and triple zeta basis sets demonstrate the power of the method for handling strong correlation. The smooth dissociation profiles that result from PP-iFCI show that FCI-quality ground state computations are now within reach for systems with up to about 10 heavy atoms.

Strand-invading linear probe combined with unmodified PNA.

PubMed

Asanuma, Hiroyuki; Niwa, Rie; Akahane, Mariko; Murayama, Keiji; Kashida, Hiromu; Kamiya, Yukiko

2016-09-15

Efficient strand invasion by a linear probe to fluorescently label double-stranded DNA has been implemented by employing a probe and unmodified PNA. As a fluorophore, we utilized ethynylperylene. Multiple ethynylperylene residues were incorporated into the DNA probe via a d-threoninol scaffold. The ethynylperylene did not significantly disrupt hybridization with complementary DNA. The linear probe self-quenched in the absence of target DNA and did not hybridize with PNA. A gel-shift assay revealed that linear probe and PNA combination invaded the central region of double-stranded DNA upon heat-shock treatment to form a double duplex. To further suppress the background emission and increase the stability of the probe/DNA duplex, a probe containing anthraquinones as well as ethynylperylene was synthesized. This probe and PNA invader pair detected an internal sequence in a double-stranded DNA with high sensitivity when heat shock treatment was used. The probe and PNA pair was able to invade at the terminus of a long double-stranded DNA at 40°C at 100mM NaCl concentration. Copyright © 2016 Elsevier Ltd. All rights reserved.

Single-Photon, Double Photodetachment of Nickel Phthalocyanine Tetrasulfonic Acid 4- Anions.

PubMed

Daly, Steven; Girod, Marion; Vojkovic, Marin; Giuliani, Alexandre; Antoine, Rodolphe; Nahon, Laurent; O'Hair, Richard A J; Dugourd, Philippe

2016-07-07

Single-photon, two-electron photodetachment from nickel phthalocyanine tetrasulfonic acid tetra anions, [NiPc](4-), was examined in the gas-phase using a linear ion trap coupled to the DESIRS VUV beamline of the SOLEIL Synchrotron. This system was chosen since it has a low detachment energy, known charge localization, and well-defined geometrical and electronic structures. A threshold for two-electron loss is observed at 10.2 eV, around 1 eV lower than previously observed double detachment thresholds on multiple charged protein anions. The photodetachment energy of [NiPc](4-) has been previously determined to be 3.5 eV and the photodetachment energy of [NiPc](3-•) is determined in this work to be 4.3 eV. The observed single photon double electron detachment threshold is hence 5.9 eV higher than the energy required for sequential single electron loss. Possible mechanisms are for double photodetachment are discussed. These observations pave the way toward new, exciting experiments for probing double photodetachment at relatively low energies, including correlation measurements on emitted photoelectrons.

Formation of template-switching artifacts by linear amplification.

PubMed

Chakravarti, Dhrubajyoti; Mailander, Paula C

2008-07-01

Linear amplification is a method of synthesizing single-stranded DNA from either a single-stranded DNA or one strand of a double-stranded DNA. In this protocol, molecules of a single primer DNA are extended by multiple rounds of DNA synthesis at high temperature using thermostable DNA polymerases. Although linear amplification generates the intended full-length single-stranded product, it is more efficient over single-stranded templates than double-stranded templates. We analyzed linear amplification over single- or double-stranded mouse H-ras DNA (exon 1-2 region). The single-stranded H-ras template yielded only the intended product. However, when the double-stranded template was used, additional artifact products were observed. Increasing the concentration of the double-stranded template produced relatively higher amounts of these artifact products. One of the artifact DNA bands could be mapped and analyzed by sequencing. It contained three template-switching products. These DNAs were formed by incomplete DNA strand extension over the template strand, followed by switching to the complementary strand at a specific Ade nucleotide within a putative hairpin sequence, from which DNA synthesis continued over the complementary strand.

HINCOF-1: a Code for Hail Ingestion in Engine Inlets

NASA Technical Reports Server (NTRS)

Gopalaswamy, N.; Murthy, S. N. B.

1995-01-01

One of the major concerns during hail ingestion into an engine is the resulting amount and space- and time-wise distribution of hail at the engine face for a given geometry of inlet and set of atmospheric and flight conditions. The appearance of hail in the capture streamtube is invariably random in space and time, with respect to size and momentum. During the motion of a hailstone through an inlet, a hailstone undergoes several processes, namely impact with other hailstones and material surfaces of the inlet and spinner, rolling and rebound following impact; heat and mass transfer; phase change; and shattering, the latter three due to friction and impact. Taking all of these factors into account, a numerical code, designated HINCOF-I, has been developed for determining the motion hailstones from the atmosphere, through an inlet, and up to the engine face. The numerical procedure is based on the Monte-Carlo method. The report presents a description of the code, along with several illustrative cases. The code can be utilized to relate the spinner geometry - conical or, more effective, elliptical - to the possible diversion of hail at the engine face into the bypass stream. The code is also useful for assessing the influence of various hail characteristics on the ingestion and distribution of hailstones over the engine face.

Flight Investigation of the Effects of Pressure-Belt Tubing Size on Measured Pressure Distributions

NASA Technical Reports Server (NTRS)

Rivers, Natale A.; vanDam, Cornielious P.; Brown, Phillip W.; Rivers, Robert A.

2001-01-01

The pressure-belt technique is commonly used to measure pressure distributions on lifting and nonlifting surfaces where flush, through-the-surface measurements are not possible. The belts, made from strips of small-bore, flexible plastic tubing, are surface-mounted by a simple, nondestructive method. Additionally, the belts require minimal installation time, thus making them much less costly to install than flush-mounted pressure ports. Although pressure belts have been used in flight research since the early 1950s, only recently have manufacturers begun to produce thinner, more flexible tubing, and thin, strong adhesive tapes that minimize the installation-induced errors on the measurement of surface pressures. The objective of this investigation was to determine the effects of pressure-belt tubing size on the measurement of pressure distributions. For that purpose, two pressure belts were mounted on the right wing of a single-engine, propeller-driven research airplane. The outboard pressure belt served as a baseline for the measurement and the comparison of effects. Each tube had an outer diameter (OD) of 0.0625 in. The inboard belt was used to evaluate three different tube sizes: 0.0625-, 0.1250-, and 0.1875-in. OD. A computational investigation of tube size on pressure distribution also was conducted using the two-dimensional Multielement Streamtube Euler Solver (MSES) code.

Floc size distributions of suspended kaolinite in an advection transport dominated tank: measurements and modeling

NASA Astrophysics Data System (ADS)

Shen, Xiaoteng; Maa, Jerome P.-Y.

2017-11-01

In estuaries and coastal waters, floc size and its statistical distributions of cohesive sediments are of primary importance, due to their effects on the settling velocity and thus deposition rates of cohesive aggregates. The development of a robust flocculation model that includes the predictions of floc size distributions (FSDs), however, is still in a research stage. In this study, a one-dimensional longitudinal (1-DL) flocculation model along a streamtube is developed. This model is based on solving the population balance equation to find the FSDs by using the quadrature method of moments. To validate this model, a laboratory experiment is carried out to produce an advection transport-dominant environment in a cylindrical tank. The flow field is generated by a marine pump mounted at the bottom center, with its outlet facing upward. This setup generates an axially symmetric flow which is measured by an acoustic Doppler velocimeter (ADV). The measurement results provide the hydrodynamic input data required for this 1-DL model. The other measurement results, the FSDs, are acquired by using an automatic underwater camera system and the resulting images are analyzed to validate the predicted FSDs. This study shows that the FSDs as well as their representative sizes can be efficiently and reasonably simulated by this 1-DL model.

Prediction of down-gradient impacts of DNAPL source depletion using tracer techniques: Laboratory and modeling validation

NASA Astrophysics Data System (ADS)

Jawitz, J. W.; Basu, N.; Chen, X.

2007-05-01

Interwell application of coupled nonreactive and reactive tracers through aquifer contaminant source zones enables quantitative characterization of aquifer heterogeneity and contaminant architecture. Parameters obtained from tracer tests are presented here in a Lagrangian framework that can be used to predict the dissolution of nonaqueous phase liquid (NAPL) contaminants. Nonreactive tracers are commonly used to provide information about travel time distributions in hydrologic systems. Reactive tracers have more recently been introduced as a tool to quantify the amount of NAPL contaminant present within the tracer swept volume. Our group has extended reactive tracer techniques to also characterize NAPL spatial distribution heterogeneity. By conceptualizing the flow field through an aquifer as a collection of streamtubes, the aquifer hydrodynamic heterogeneities may be characterized by a nonreactive tracer travel time distribution, and NAPL spatial distribution heterogeneity may be similarly described using reactive travel time distributions. The combined statistics of these distributions are used to derive a simple analytical solution for contaminant dissolution. This analytical solution, and the tracer techniques used for its parameterization, were validated both numerically and experimentally. Illustrative applications are presented from numerical simulations using the multiphase flow and transport simulator UTCHEM, and laboratory experiments of surfactant-enhanced NAPL remediation in two-dimensional flow chambers.

Musicians have enhanced audiovisual multisensory binding: experience-dependent effects in the double-flash illusion.

PubMed

Bidelman, Gavin M

2016-10-01

Musical training is associated with behavioral and neurophysiological enhancements in auditory processing for both musical and nonmusical sounds (e.g., speech). Yet, whether the benefits of musicianship extend beyond enhancements to auditory-specific skills and impact multisensory (e.g., audiovisual) processing has yet to be fully validated. Here, we investigated multisensory integration of auditory and visual information in musicians and nonmusicians using a double-flash illusion, whereby the presentation of multiple auditory stimuli (beeps) concurrent with a single visual object (flash) induces an illusory perception of multiple flashes. We parametrically varied the onset asynchrony between auditory and visual events (leads and lags of ±300 ms) to quantify participants' "temporal window" of integration, i.e., stimuli in which auditory and visual cues were fused into a single percept. Results show that musically trained individuals were both faster and more accurate at processing concurrent audiovisual cues than their nonmusician peers; nonmusicians had a higher susceptibility for responding to audiovisual illusions and perceived double flashes over an extended range of onset asynchronies compared to trained musicians. Moreover, temporal window estimates indicated that musicians' windows (<100 ms) were ~2-3× shorter than nonmusicians' (~200 ms), suggesting more refined multisensory integration and audiovisual binding. Collectively, findings indicate a more refined binding of auditory and visual cues in musically trained individuals. We conclude that experience-dependent plasticity of intensive musical experience extends beyond simple listening skills, improving multimodal processing and the integration of multiple sensory systems in a domain-general manner.

Multiple composite grafts (k, π or double-Y) in coronary artery surgery: a choice or a necessity?

PubMed

Mannacio, Vito; Cirillo, Plinio; Mannacio, Luigi; Antignano, Anita; Mottola, Michele; Vosa, Carlo

2015-01-01

Composite grafts allow complete arterial revascularization with minimal aortic manipulations. The Y-T configuration supplies all distal branches adequately, whereas it is unclear whether complex composite configurations (K, Π or double-Y) are equally at rest or when challenged by maximal requirements. Forty-seven patients who underwent off-pump coronary artery revascularization by multiple arterial composite grafts (K, Π or double-Y) were retrospectively evaluated. Indication for this surgical option was porcelain aorta or conduit unavailability. Composite systems were evaluated by intraoperative flow measurements and perioperative transthoracic Doppler ultrasonography, 12 months later also by exercise test, sestamibi scintigraphy at rest and during induced hyperaemia and by 64-slice multidetector CT angiography. A total of 141 distal anastomoses were implanted as composite grafts. Perioperative flow measurements and 12-month Doppler ultrasonography were adequate at rest. At stress test, chest pain and/or induced ECG evidence of ischaemia are found in 16 patients (39%). During dipyridamole-induced hyperaemia, single-photon emission computed tomography image revealed that mean summed stress score was 7.2 ± 5.7, summed difference score 5.3 ± 4.2 and coronary flow reserve 1.7 ± 0.2. Multiple composite grafts, albeit adequate at rest, were unable to meet flow requirements during maximal hyperaemia. In daily practice, their use must be not a choice but rather a necessity in those patients without alternative options. © The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

Multiple System Atrophy (MSA)

MedlinePlus

... coordination, such as unsteady gait and loss of balance Slurred, slow or low-volume speech (dysarthria) Visual disturbances, such as blurred or double vision and difficulty focusing your eyes Difficulty swallowing (dysphagia) or chewing General signs and symptoms In addition, the primary sign ...

Expression of the stem cell factor in fibroblasts, endothelial cells, and macrophages in periapical tissues in human chronic periapical diseases.

PubMed

Shen, S Q; Wang, R; Huang, S G

2017-03-08

Stem cell factor (SCF), an important stem cell cytokine, has multiple functions. Fibroblasts (FBs), mature mast cells, endothelial cells (ECs), and eosinophil granulocytes can produce SCF in the inflammatory process. Therefore, we aimed to observe SCF expression in FBs, ECs, and macrophages (MPs) in periapical tissues in human chronic periapical disease and investigate the effects of cells expressing SCF in pathogenesis of the disease. Healthy (N = 20), periapical cyst (N = 15), and periapical granuloma (N = 15) tissues were fixed in 10% formalin for 48 h, embedded in paraffin, and stained with hematoxylin and eosin to observe histological changes. SCF expression was observed in FBs, ECs, and MPs in periapical tissues by double immunofluorescence. CD334, CD31, and CD14 are specific markers of FBs, ECs, and MPs, respectively. Results showed that densities of CD334-SCF double-positive FBs, CD31-SCF double-positive ECs, and CD14-SCF double-positive MPs were significantly increased in periapical tissue groups (P < 0.01). There were no significant differences in CD334-SCF double-positive FB and CD31-SCF double-positive EC levels between the two periapical tissue groups (P > 0.05). CD14-SCF double-positive MP density was considerably higher in periapical granulomas than in cysts (P < 0.01). FB, EC, and MP levels were significantly high and densities of CD334-SCF double-positive FBs, CD31-SCF double-positive ECs, and CD14-SCF double-positive MPs improved considerably in chronic periapical tissues, suggesting that the cells might be related to occurrence, development, and pathogenesis of chronic periapical disease.

Two-dimensional quasi-double-layers in two-electron-temperature, current-free plasmas

NASA Astrophysics Data System (ADS)

Merino, Mario; Ahedo, Eduardo

2013-02-01

The expansion of a plasma with two disparate electron populations into vacuum and channeled by a divergent magnetic nozzle is analyzed with an axisymmetric model. The purpose is to study the formation and two-dimensional shape of a current-free double-layer in the case when the electric potential steepening can still be treated within the quasineutral approximation. The properties of this quasi-double-layer are investigated in terms of the relative fraction of the high-energy electron population, its radial distribution when injected into the nozzle, and the geometry and intensity of the applied magnetic field. The two-dimensional double layer presents a curved shape, which is dependent on the natural curvature of the equipotential lines in a magnetically expanded plasma and the particular radial distribution of high-energy electrons at injection. The double layer curvature increases the higher the nozzle divergence is, the lower the magnetic strength is, and the more peripherally hot electrons are injected. A central application of the study is the operation of a helicon plasma thruster in space. To this respect, it is shown that the curvature of the double layer does not increment the thrust, it does not modify appreciably the downstream divergence of the plasma beam, but it increases the magnetic-to-pressure thrust ratio. The present study does not attempt to cover current-free double layers involving plasmas with multiple populations of positive ions.

Combining Formal and Informal Caregiving Roles: The Psychosocial Implications of Double- and Triple-Duty Care

PubMed Central

Davis, Kelly D.; Zarit, Steven H.; Moen, Phyllis; Hammer, Leslie B.; Almeida, David M.

2016-01-01

Objectives. Women who combine formal and informal caregiving roles represent a unique, understudied population. In the literature, healthcare employees who simultaneously provide unpaid elder care at home have been referred to as double-duty caregivers. The present study broadens this perspective by examining the psychosocial implications of double-duty child care (child care only), double-duty elder care (elder care only), and triple-duty care (both child care and elder care or “sandwiched” care). Method. Drawing from the Work, Family, and Health Study, we focus on a large sample of women working in nursing homes in the United States (n = 1,399). We use multiple regression analysis and analysis of covariance tests to examine a range of psychosocial implications associated with double- and triple-duty care. Results. Compared with nonfamily caregivers, double-duty child caregivers indicated greater family-to-work conflict and poorer partner relationship quality. Double-duty elder caregivers reported more family-to-work conflict, perceived stress, and psychological distress, whereas triple-duty caregivers indicated poorer psychosocial functioning overall. Discussion. Relative to their counterparts without family caregiving roles, women with combined caregiving roles reported poorer psychosocial well-being. Additional research on women with combined caregiving roles, especially triple-duty caregivers, should be a priority amidst an aging population, older workforce, and growing number of working caregivers. PMID:25271309

DAMe: a toolkit for the initial processing of datasets with PCR replicates of double-tagged amplicons for DNA metabarcoding analyses.

PubMed

Zepeda-Mendoza, Marie Lisandra; Bohmann, Kristine; Carmona Baez, Aldo; Gilbert, M Thomas P

2016-05-03

DNA metabarcoding is an approach for identifying multiple taxa in an environmental sample using specific genetic loci and taxa-specific primers. When combined with high-throughput sequencing it enables the taxonomic characterization of large numbers of samples in a relatively time- and cost-efficient manner. One recent laboratory development is the addition of 5'-nucleotide tags to both primers producing double-tagged amplicons and the use of multiple PCR replicates to filter erroneous sequences. However, there is currently no available toolkit for the straightforward analysis of datasets produced in this way. We present DAMe, a toolkit for the processing of datasets generated by double-tagged amplicons from multiple PCR replicates derived from an unlimited number of samples. Specifically, DAMe can be used to (i) sort amplicons by tag combination, (ii) evaluate PCR replicates dissimilarity, and (iii) filter sequences derived from sequencing/PCR errors, chimeras, and contamination. This is attained by calculating the following parameters: (i) sequence content similarity between the PCR replicates from each sample, (ii) reproducibility of each unique sequence across the PCR replicates, and (iii) copy number of the unique sequences in each PCR replicate. We showcase the insights that can be obtained using DAMe prior to taxonomic assignment, by applying it to two real datasets that vary in their complexity regarding number of samples, sequencing libraries, PCR replicates, and used tag combinations. Finally, we use a third mock dataset to demonstrate the impact and importance of filtering the sequences with DAMe. DAMe allows the user-friendly manipulation of amplicons derived from multiple samples with PCR replicates built in a single or multiple sequencing libraries. It allows the user to: (i) collapse amplicons into unique sequences and sort them by tag combination while retaining the sample identifier and copy number information, (ii) identify sequences carrying unused tag combinations, (iii) evaluate the comparability of PCR replicates of the same sample, and (iv) filter tagged amplicons from a number of PCR replicates using parameters of minimum length, copy number, and reproducibility across the PCR replicates. This enables an efficient analysis of complex datasets, and ultimately increases the ease of handling datasets from large-scale studies.

Enhancing the performance of blue GaN-based light emitting diodes with double electron blocking layers

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

Guo, Yao; Liang, Meng; Fu, Jiajia

2015-03-15

In this work, novel double Electron Blocking Layers for InGaN/GaN multiple quantum wells light-emitting diodes were proposed to mitigate the efficiency droop at high current density. The band diagram and carriers distributions were investigated numerically. The results indicate that due to a newly formed holes stack in the p-GaN near the active region, the hole injection has been improved and an uniform carriers distribution can be achieved. As a result, in our new structure with double Electron Blocking Layers, the efficiency droop has been reduced to 15.5 % in comparison with 57.3 % for the LED with AlGaN EBL atmore » the current density of 100 A/cm{sup 2}.« less

Multiple-membrane multiple-electrolyte redox flow battery design

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

Yan, Yushan; Gu, Shuang; Gong, Ke

A redox flow battery is provided. The redox flow battery involves multiple-membrane (at least one cation exchange membrane and at least one anion exchange membrane), multiple-electrolyte (one electrolyte in contact with the negative electrode, one electrolyte in contact with the positive electrode, and at least one electrolyte disposed between the two membranes) as the basic characteristic, such as a double-membrane, triple electrolyte (DMTE) configuration or a triple-membrane, quadruple electrolyte (TMQE) configuration. The cation exchange membrane is used to separate the negative or positive electrolyte and the middle electrolyte, and the anion exchange membrane is used to separate the middle electrolytemore » and the positive or negative electrolyte.« less

A Study on Double Event Detection for PHENIX at RHIC

NASA Astrophysics Data System (ADS)

Vazquez-Carson, Sebastian; Phenix Collaboration

2016-09-01

Many measurements made in Heavy Ion experiments such as PHENIX at RHIC focus on geometrical properties because phenomena such as collective flow give insight into quark-gluon plasma and the strong nuclear force. As part of this investigation, PHENIX has taken data in 2016 for deuteron on gold collisions at several energies. An acceptable luminosity is achieved by injecting up to 120 separate bunches each with billions of ions into the storage ring, from which two, separate beams are made to collide. This method has a drawback as there is a chance for multiple pairs of nuclei to collide in a single bunch crossing. Data taken in a double event cannot be separated into two independent events and has no clear interpretation. This effect's magnitude is estimated and incorporated in published results as a systematic uncertainty and studies on this topic have already been conducted within PHENIX. I develop several additional algorithms to flag multiple interaction events by examining the time dependence of data from the two Beam-Beam Counters - detectors surrounding the beam pipe on opposite ends of the interaction region. The algorithms are tested with data, in which events with double interactions are artificially produced using low luminosity data. I am working at the University of Colorado at Boulder on behalf of the PHENIX collaboration.

Multiple parton interactions and forward double pion production in pp and dA scattering

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

Strikman, M.; Vogelsang, W.

2011-02-01

We estimate the contributions by double-parton interactions to the cross sections for pp{yields}{pi}{sup 0}{pi}{sup 0}X and dA{yields}{pi}{sup 0}{pi}{sup 0}X at the Relativistic Heavy Ion Collider (RHIC). We find that such contributions become important at large forward rapidities of the produced pions. This is, in particular, the case for dA scattering, where they strongly enhance the azimuthal-angular independent pedestal component of the cross section, providing a natural explanation of this feature of the RHIC dA data. We argue that the discussed processes open a window to studies of double quark distributions in nucleons. We also briefly address the roles of shadowingmore » and energy loss in dA scattering, which we show to affect the double-inclusive pion cross section much more strongly than the single-inclusive one. We discuss the implications of our results for the interpretation of pion azimuthal correlations.« less

Acoustic contributions of a sound absorbing blanket placed in a double panel structure: absorption versus transmission.

PubMed

Doutres, Olivier; Atalla, Noureddine

2010-08-01

The objective of this paper is to propose a simple tool to estimate the absorption vs. transmission loss contributions of a multilayered blanket unbounded in a double panel structure and thus guide its optimization. The normal incidence airborne sound transmission loss of the double panel structure, without structure-borne connections, is written in terms of three main contributions; (i) sound transmission loss of the panels, (ii) sound transmission loss of the blanket and (iii) sound absorption due to multiple reflections inside the cavity. The method is applied to four different blankets frequently used in automotive and aeronautic applications: a non-symmetric multilayer made of a screen in sandwich between two porous layers and three symmetric porous layers having different pore geometries. It is shown that the absorption behavior of the blanket controls the acoustic behavior of the treatment at low and medium frequencies and its transmission loss at high frequencies. Acoustic treatment having poor sound absorption behavior can affect the performance of the double panel structure.

Independent Origin of Plasmodium falciparum Antifolate Super-Resistance, Uganda, Tanzania, and Ethiopia

PubMed Central

Alifrangis, Michael; Schousboe, Mette L.; Ishengoma, Deus; Lusingu, John; Pota, Hirva; Kavishe, Reginald A.; Pearce, Richard; Ord, Rosalynn; Lynch, Caroline; Dejene, Seyoum; Cox, Jonathan; Rwakimari, John; Minja, Daniel T.R.; Lemnge, Martha M.; Roper, Cally

2014-01-01

Super-resistant Plasmodium falciparum threatens the effectiveness of sulfadoxine–pyrimethamine in intermittent preventive treatment for malaria during pregnancy. It is characterized by the A581G Pfdhps mutation on a background of the double-mutant Pfdhps and the triple-mutant Pfdhfr. Using samples collected during 2004–2008, we investigated the evolutionary origin of the A581G mutation by characterizing microsatellite diversity flanking Pfdhps triple-mutant (437G+540E+581G) alleles from 3 locations in eastern Africa and comparing it with double-mutant (437G+540E) alleles from the same area. In Ethiopia, both alleles derived from 1 lineage that was distinct from those in Uganda and Tanzania. Uganda and Tanzania triple mutants derived from the previously characterized southeastern Africa double-mutant lineage. The A581G mutation has occurred multiple times on local Pfdhps double-mutant backgrounds; however, a novel microsatellite allele incorporated into the Tanzania lineage since 2004 illustrates the local expansion of emergent triple-mutant lineages. PMID:25061906

Pre-coding method and apparatus for multiple source or time-shifted single source data and corresponding inverse post-decoding method and apparatus

NASA Technical Reports Server (NTRS)

Yeh, Pen-Shu (Inventor)

1997-01-01

A pre-coding method and device for improving data compression performance by removing correlation between a first original data set and a second original data set, each having M members, respectively. The pre-coding method produces a compression-efficiency-enhancing double-difference data set. The method and device produce a double-difference data set, i.e., an adjacent-delta calculation performed on a cross-delta data set or a cross-delta calculation performed on two adjacent-delta data sets, from either one of (1) two adjacent spectral bands coming from two discrete sources, respectively, or (2) two time-shifted data sets coming from a single source. The resulting double-difference data set is then coded using either a distortionless data encoding scheme (entropy encoding) or a lossy data compression scheme. Also, a post-decoding method and device for recovering a second original data set having been represented by such a double-difference data set.

Pre-coding method and apparatus for multiple source or time-shifted single source data and corresponding inverse post-decoding method and apparatus

NASA Technical Reports Server (NTRS)

Yeh, Pen-Shu (Inventor)

1998-01-01

A pre-coding method and device for improving data compression performance by removing correlation between a first original data set and a second original data set, each having M members, respectively. The pre-coding method produces a compression-efficiency-enhancing double-difference data set. The method and device produce a double-difference data set, i.e., an adjacent-delta calculation performed on a cross-delta data set or a cross-delta calculation performed on two adjacent-delta data sets, from either one of (1) two adjacent spectral bands coming from two discrete sources, respectively, or (2) two time-shifted data sets coming from a single source. The resulting double-difference data set is then coded using either a distortionless data encoding scheme (entropy encoding) or a lossy data compression scheme. Also, a post-decoding method and device for recovering a second original data set having been represented by such a double-difference data set.

Sexual conflict over mating in a spider: increased fecundity does not compensate for the costs of polyandry.

PubMed

Maklakov, Alexei A; Lubin, Yael

2004-05-01

Female multiple mating (polyandry) is a widespread but costly behavior that remains poorly understood. Polyandry may arise when whatever benefits females accrue from multiple mating outweigh the costs, or males manipulate females against the females' best interests. In a polyandrous spider Stegodyphus lineatus females may mate with up to five males, but behave aggressively toward additional males after the first mating. Female aggressiveness may act to select for better quality males. Alternatively, females may try to avoid superfluous matings. To test these alternatives, we allocated females into single-mating (SM) and double-mating treatments. Double-mated females either accepted (DM) or rejected (RE) the second male. DM females laid more eggs, but did not produce more offspring than SM and RE females. Offspring of DM females were smaller at dispersal than offspring of SM and RE females. Also, nest failure was significantly more common in DM females. Paternal variables did not influence female reproductive success, whereas maternal body condition explained much of the variation. We show that polyandry is costly for females despite the production of larger clutches and suggest that multiple mating results from male manipulation of female remating behavior.

The separate universe approach to soft limits

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

Kenton, Zachary; Mulryne, David J., E-mail: z.a.kenton@qmul.ac.uk, E-mail: d.mulryne@qmul.ac.uk

We develop a formalism for calculating soft limits of n -point inflationary correlation functions using separate universe techniques. Our method naturally allows for multiple fields and leads to an elegant diagrammatic approach. As an application we focus on the trispectrum produced by inflation with multiple light fields, giving explicit formulae for all possible single- and double-soft limits. We also investigate consistency relations and present an infinite tower of inequalities between soft correlation functions which generalise the Suyama-Yamaguchi inequality.

Crossed-clip strangulation for the management of small intestinal polyps in patients with Peutz-Jeghers syndrome.

PubMed

Yano, Tomonori; Shinozaki, Satoshi; Yamamoto, Hironori

2018-05-19

Peutz-Jeghers syndrome is an autosomal dominant disorder with multiple hamartomatous polyps throughout the gastrointestinal tract. The clinical history of patients with Peutz-Jeghers syndrome usually includes multiple laparotomies to treat intestinal obstruction caused by polyps. The development of double-balloon enteroscopy enables endoscopic resection of polyps, even in the distal small intestine. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Double hemibody irradiation (DHBI) in the management of relapsed and primary chemoresistant multiple myeloma.

PubMed

McSweeney, E N; Tobias, J S; Blackman, G; Goldstone, A H; Richards, J D

1993-01-01

In view of increasing controversy regarding the role of double hemibody irradiation (DHBI) in the treatment of multiple myeloma, we have analysed the use of this technique at our institution over a 6-year period. Fifty-five patients with multiple myeloma were treated with both upper and lower hemibody irradiation between January 1985 and January 1991; 42 had relapsed post-plateau and 13 were chemoresistant to initial therapy. Fifteen patients received alpha IFN-2b maintenance therapy post-DHBI, at a dose of 3 Mu three times per week, as part of a randomized trial. Ninety-five per cent of patients experienced symptomatic improvement in bone pain post-DHBI, 21% of whom discontinued opiate analgesics altogether; 63% had a minor biochemical response and 38% had a partial biochemical response. The overall survival (OS) and progression free survivals (PFS) in all patients were 11 months and 8 months respectively. No significant difference was noted in either OS or PFS, according to whether patients were chemoresistant or had relapsed post-plateau. alpha IFN did not appear to prolong survival (OS or PFS) post-DHBI. Cytopenia was a significant problem, such that only 60% of patients had counts adequate enough to be eligible for alpha IFN. We conclude that DHBI is an effective treatment in patients with relapsed multiple myeloma and in those who are chemoresistant to initial therapy.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of velocity-dependent friction on multiple-vehicle collisions in traffic flow

NASA Astrophysics Data System (ADS)

Nagatani, Takashi

2017-01-01

We present the dynamic model for the multiple-vehicle collisions to take into account the velocity-dependent friction force. We study the effect of the velocity-dependent friction on the chain-reaction crash on a road. In the traffic situation, drivers brake according to taillights of the forward vehicle and the friction force depends highly on the vehicular speed. The first crash may induce more collisions. We investigate whether or not the first collision induces the multiple-vehicle collisions, numerically and analytically. The dynamic transitions occur from no collisions, through a single collision and double collisions, to multiple collisions with decreasing the headway. We explore the effect of the velocity-dependent friction on the dynamic transitions and the region maps in the multiple-vehicle collisions.

Double and multiple contacts of similar elastic materials

NASA Astrophysics Data System (ADS)

Sundaram, Narayan K.

Ongoing fretting fatigue research has focussed on developing robust contact mechanics solutions for complicated load histories involving normal, shear, moment and bulk loads. For certain indenter profiles and applied loads, the contact patch separates into two disconnected regions. Existing Singular Integral Equation (SIE) techniques do not address these situations. A fast numerical tool is developed to solve such problems for similar elastic materials for a wide range of profiles and load paths including applied moments and remote bulk-stress effects. This tool is then used to investigate two problems in double contacts. The first, to determine the shear configuration space for a biquadratic punch for the generalized Cattaneo-Mindlin problem. The second, to obtain quantitative estimates of the interaction between neighboring cylindrical contacts for both the applied normal load and partial slip problems up to the limits of validity of the halfspace assumption. In double contact problems without symmetry, obtaining a unique solution requires the satisfaction of a condition relating the contact ends, rigid-body rotation and profile function. This condition has the interpretation that a rigid-rod connecting the inner contact ends of an equivalent frictionless double contact of a rigid indenter and halfspace may only undergo rigid body motions. It is also found that the ends of stick-zones, local slips and remote-applied strains in double contact problems are related by an equation expressing tangential surface-displacement continuity. This equation is essential to solve partial-slip problems without contact equivalents. Even when neighboring cylindrical contacts may be treated as non-interacting for the purpose of determining the pressure tractions, this is not generally true if a shear load is applied. The mutual influence of neighboring contacts in partial slip problems is largest at small shear load fractions. For both the pressure and partial slip problems, the interactions are stronger with increasing strength of loading and contact proximity. A new contact algorithm is developed and the SIE method extended to tackle contact problems with an arbitrary number of contact patches with no approximations made about contact interactions. In the case of multiple contact problems determining the correct contact configuration is significantly more complicated than in double contacts, necessitating a new approach. Both the normal contact and partial slip problems are solved. The tool is then used to study contacts of regular rough cylinders, a flat with rounded punch with superimposed sinusoidal roughness and is also applied to analyze the contact of an experimental rough surface with a halfspace. The partial slip results for multiple-contacts are generally consistent with Cattaneo-Mindlin continuum scale results, in that the outermost contacts tend to be in full sliding. Lastly, the influence of plasticity on frictionless multiple contact problems is studied using FEM for two common steel and aluminum alloys. The key findings are that the plasticity decreases the peak pressure and increases both real and apparent contact areas, thus 'blunting' the sharp pressures caused by the contact asperities in pure elasticity. Further, it is found that contact plasticity effects and load for onset of first yield are strongly dependent on roughness amplitude, with higher plasticity effects and lower yield-onset load at higher roughness amplitudes.

An oligonucleotide microarray to characterize multidrug resistant plasmids

USDA-ARS?s Scientific Manuscript database

Bacteria plasmids are fragments of extra-chromosomal double stranded deoxyribonucleic acid (DNA) that can contain a variety of genes beneficial to the host organism like antibiotic drug resistance. Many of the Enterobacteriaceae carry multiple drug resistance (MDR) genes on large plasmids of replic...

Preliminary calibration of the ACP safeguards neutron counter

NASA Astrophysics Data System (ADS)

Lee, T. H.; Kim, H. D.; Yoon, J. S.; Lee, S. Y.; Swinhoe, M.; Menlove, H. O.

2007-10-01

The Advanced Spent Fuel Conditioning Process (ACP), a kind of pyroprocess, has been developed at the Korea Atomic Energy Research Institute (KAERI). Since there is no IAEA safeguards criteria for this process, KAERI has developed a neutron coincidence counter to make it possible to perform a material control and accounting (MC&A) for its ACP materials for the purpose of a transparency in the peaceful uses of nuclear materials at KAERI. The test results of the ACP Safeguards Neutron Counter (ASNC) show a satisfactory performance for the Doubles count measurement with a low measurement error for its cylindrical sample cavity. The neutron detection efficiency is about 21% with an error of ±1.32% along the axial direction of the cavity. Using two 252Cf neutron sources, we obtained various parameters for the Singles and Doubles rates for the ASNC. The Singles, Doubles, and Triples rates for a 252Cf point source were obtained by using the MCNPX code and the results for the ft8 cap multiplicity tally option with the values of ɛ, fd, and ft measured with a strong source most closely match the measurement results to within a 1% error. A preliminary calibration curve for the ASNC was generated by using the point model equation relationship between 244Cm and 252Cf and the calibration coefficient for the non-multiplying sample is 2.78×10 5 (Doubles counts/s/g 244Cm). The preliminary calibration curves for the ACP samples were also obtained by using an MCNPX simulation. A neutron multiplication influence on an increase of the Doubles rate for a metal ingot and UO2 powder is clearly observed. These calibration curves will be modified and complemented, when hot calibration samples become available. To verify the validity of this calibration curve, a measurement of spent fuel standards for a known 244Cm mass will be performed in the near future.

Process variation challenges and resolution in the negative-tone develop double patterning for 20nm and below technology node

NASA Astrophysics Data System (ADS)

Mehta, Sohan S.; Ganta, Lakshmi K.; Chauhan, Vikrant; Wu, Yixu; Singh, Sunil; Ann, Chia; Subramany, Lokesh; Higgins, Craig; Erenturk, Burcin; Srivastava, Ravi; Singh, Paramjit; Koh, Hui Peng; Cho, David

2015-03-01

Immersion based 20nm technology node and below becoming very challenging to chip designers, process and integration due to multiple patterning to integrate one design layer . Negative tone development (NTD) processes have been well accepted by industry experts for enabling technologies 20 nm and below. 193i double patterning is the technology solution for pitch down to 80 nm. This imposes tight control in critical dimension(CD) variation in double patterning where design patterns are decomposed in two different masks such as in litho-etch-litho etch (LELE). CD bimodality has been widely studied in LELE double patterning. A portion of CD tolerance budget is significantly consumed by variations in CD in double patterning. The objective of this work is to study the process variation challenges and resolution in the Negative Tone Develop Process for 20 nm and Below Technology Node. This paper describes the effect of dose slope on CD variation in negative tone develop LELE process. This effect becomes even more challenging with standalone NTD developer process due to q-time driven CD variation. We studied impact of different stacks with combination of binary and attenuated phase shift mask and estimated dose slope contribution individually from stack and mask type. Mask 3D simulation was carried out to understand theoretical aspect. In order to meet the minimum insulator requirement for the worst case on wafer the overlay and critical dimension uniformity (CDU) budget margins have slimmed. Besides the litho process and tool control using enhanced metrology feedback, the variation control has other dependencies too. Color balancing between the two masks in LELE is helpful in countering effects such as iso-dense bias, and pattern shifting. Dummy insertion and the improved decomposition techniques [2] using multiple lower priority constraints can help to a great extent. Innovative color aware routing techniques [3] can also help with achieving more uniform density and color balanced layouts.

Measurement of theta13 in the double Chooz experiment

NASA Astrophysics Data System (ADS)

Yang, Guang

Neutrino oscillation has been established for over a decade. The mixing angle theta13 is one of the parameters that is most difficult to measure due to its small value. Currently, reactor antineutrino experiments provide the best knowledge of theta13, using the electron antineutrino disappearance phenomenon. The most compelling advantage is the high intensity of the reactor antineutrino rate. The Double Chooz experiment, located on the border of France and Belgium, is such an experiment, which aims to have one of the most precise theta 13 measurements in the world. Double Chooz has a single-detector phase and a double-detector phase. For the single-detector phase, the limit of the theta 13 sensitivity comes mostly from the reactor flux. However, the uncertainty on the reactor flux is highly suppressed in the double-detector phase. Oscillation analyses for the two phases have different strategies but need similar inputs, including background estimation, detection systematics evaluation, energy reconstruction and so on. The Double Chooz detectors are filled with gadolinium (Gd) doped liquid scintillator and use the inverse beta decay (IBD) signal so that for each phase, there are two independent theta13 measurements based on different neutron capturer (Gd or hydrogen). Multiple oscillation analyses are performed to provide the best 13 results. In addition to the 13 measurement, Double Chooz is also an excellent \\playground" to do diverse physics research. For example, a 252Cf calibration source study has been done to understand the spontaneous decay of this radioactive source. Further, Double Chooz also has the ability to do a sterile neutrino search in a certain mass region. Moreover, some new physics ideas can be tested in Double Chooz. In this thesis, the detailed methods to provide precise theta13 measurement will be described and the other physics topics will be introduced.

Successful new anti-sloughing drilling fluid application, Yanchang gas field, China

NASA Astrophysics Data System (ADS)

He, Peng; Liu, Hanmei; Du, Sen; He, Chenghai

2017-10-01

Borehole collapse had always been encountered when drilling the Shiqianfeng and Shihezi formations in Yan Chang gas field. By analyzing the reasons for the collapse can be obtained, "double layer of stone" brittle strong, pore development, water sensitivity and high mineral content filling skeleton particles, water lock effect and stress sensitivity is a potential factor in inducing strong wall collapse. According to the characteristics of the geological structure developed anti-sloughing drilling fluid system "double layer of stone," "complex fluid loss - dual inhibition - materialized block" multiple cooperative mechanism to achieve the purpose of anti-collapse.

VizieR Online Data Catalog: The Washington Visual Double Star Catalog (Mason+ 2001-2014)

NASA Astrophysics Data System (ADS)

Mason, B. D.; Wycoff, G. L.; Hartkopf, W. I.; Douglass, G. G.; Worley, C. E.

2016-03-01

The Washington Visual Double Star Catalog (WDS) is the successor to the Index Catalogue of Visual Double Stars, 1961.0 (IDS; Jeffers and van den Bos, Publ. Lick Obs. 21). Three earlier double star catalogs in XXth century, those by Burnham (BDS, 1906, "General Catalogue of Double Stars within 121 degrees of the North Pole", Carnegie Institution of Washington), Innes (SDS, 1927, "Southern Double Star Catalogue -19 to -90 degrees", Union Observatory, Johannesburg, South Africa), and Aitken (ADS, 1932 "New General Catalogue of Double Stars within 121 degrees of the North Pole", Carnegie Institution of Washington), each covered only a portion of the sky. Both the IDS and the WDS cover the entire sky, and the WDS is intended to contain all known visual double stars for which at least one differential measure has been published. The WDS is continually updated as published data become available. Prior to this, three major updates have been published (Worley and Douglass 1984, "Washington Visual Double Star Catalog, 1984.0", U.S. Naval Observatory, Washington; Worley and Douglass 1997A&AS..125..523W, Cat. I/237; Mason, Wycoff, Hartkopf, Douglass and Worley 2001AJ....122.3466M; and Mason et al. 2006.5). The Washington Double Star Catalog (WDS) has seen numerous changes since the last major release of the catalog. The application of many techniques and considerable industry over the past few years has yielded significant gains in both the number of systems and the number of measures. Is is maintained by the US Naval Observatory, and represents the world's principal database of astrometric double and multiple star information. The WDS contains positions (J2000), discoverer designations, epochs, position angles, separations, magnitudes, spectral types, proper motions, and, when available, Durchmusterung numbers and notes for the components of the systems. (3 data files).

VizieR Online Data Catalog: The Washington Visual Double Star Catalog (Mason+ 2001-2014)

NASA Astrophysics Data System (ADS)

Mason, B. D.; Wycoff, G. L.; Hartkopf, W. I.; Douglass, G. G.; Worley, C. E.

2014-11-01

The Washington Visual Double Star Catalog (WDS) is the successor to the Index Catalogue of Visual Double Stars, 1961.0 (IDS; Jeffers and van den Bos, Publ. Lick Obs. 21). Three earlier double star catalogs in XXth century, those by Burnham (BDS, 1906, "General Catalogue of Double Stars within 121 degrees of the North Pole", Carnegie Institution of Washington), Innes (SDS, 1927, "Southern Double Star Catalogue -19 to -90 degrees", Union Observatory, Johannesburg, South Africa), and Aitken (ADS, 1932 "New General Catalogue of Double Stars within 121 degrees of the North Pole", Carnegie Institution of Washington), each covered only a portion of the sky. Both the IDS and the WDS cover the entire sky, and the WDS is intended to contain all known visual double stars for which at least one differential measure has been published. The WDS is continually updated as published data become available. Prior to this, three major updates have been published (Worley and Douglass 1984, "Washington Visual Double Star Catalog, 1984.0", U.S. Naval Observatory, Washington; Worley and Douglass 1997A&AS..125..523W, Cat. I/237; Mason, Wycoff, Hartkopf, Douglass and Worley 2001AJ....122.3466M; and Mason et al. 2006.5). The Washington Double Star Catalog (WDS) has seen numerous changes since the last major release of the catalog. The application of many techniques and considerable industry over the past few years has yielded significant gains in both the number of systems and the number of measures. Is is maintained by the US Naval Observatory, and represents the world's principal database of astrometric double and multiple star information. The WDS contains positions (J2000), discoverer designations, epochs, position angles, separations, magnitudes, spectral types, proper motions, and, when available, Durchmusterung numbers and notes for the components of the systems. (3 data files).

VizieR Online Data Catalog: The Washington Visual Double Star Catalog (Mason+ 2001-2014)

NASA Astrophysics Data System (ADS)

Mason, B. D.; Wycoff, G. L.; Hartkopf, W. I.; Douglass, G. G.; Worley, C. E.

2015-11-01

The Washington Visual Double Star Catalog (WDS) is the successor to the Index Catalogue of Visual Double Stars, 1961.0 (IDS; Jeffers and van den Bos, Publ. Lick Obs. 21). Three earlier double star catalogs in XXth century, those by Burnham (BDS, 1906, "General Catalogue of Double Stars within 121 degrees of the North Pole", Carnegie Institution of Washington), Innes (SDS, 1927, "Southern Double Star Catalogue -19 to -90 degrees", Union Observatory, Johannesburg, South Africa), and Aitken (ADS, 1932 "New General Catalogue of Double Stars within 121 degrees of the North Pole", Carnegie Institution of Washington), each covered only a portion of the sky. Both the IDS and the WDS cover the entire sky, and the WDS is intended to contain all known visual double stars for which at least one differential measure has been published. The WDS is continually updated as published data become available. Prior to this, three major updates have been published (Worley and Douglass 1984, "Washington Visual Double Star Catalog, 1984.0", U.S. Naval Observatory, Washington; Worley and Douglass 1997A&AS..125..523W, Cat. I/237; Mason, Wycoff, Hartkopf, Douglass and Worley 2001AJ....122.3466M; and Mason et al. 2006.5). The Washington Double Star Catalog (WDS) has seen numerous changes since the last major release of the catalog. The application of many techniques and considerable industry over the past few years has yielded significant gains in both the number of systems and the number of measures. Is is maintained by the US Naval Observatory, and represents the world's principal database of astrometric double and multiple star information. The WDS contains positions (J2000), discoverer designations, epochs, position angles, separations, magnitudes, spectral types, proper motions, and, when available, Durchmusterung numbers and notes for the components of the systems. (3 data files).

VizieR Online Data Catalog: The Washington Visual Double Star Catalog (Mason+ 2001-2012)

NASA Astrophysics Data System (ADS)

Mason, B. D.; Wycoff, G. L.; Hartkopf, W. I.; Douglass, G. G.; Worley, C. E.

2012-11-01

The Washington Visual Double Star Catalog (WDS) is the successor to the Index Catalogue of Visual Double Stars, 1961.0 (IDS; Jeffers and van den Bos, Publ. Lick Obs. 21). Three earlier double star catalogs in XXth century, those by Burnham (BDS, 1906, "General Catalogue of Double Stars within 121 degrees of the North Pole", Carnegie Institution of Washington), Innes (SDS, 1927, "Southern Double Star Catalogue -19 to -90 degrees", Union Observatory, Johannesburg, South Africa), and Aitken (ADS, 1932 "New General Catalogue of Double Stars within 121 degrees of the North Pole", Carnegie Institution of Washington), each covered only a portion of the sky. Both the IDS and the WDS cover the entire sky, and the WDS is intended to contain all known visual double stars for which at least one differential measure has been published. The WDS is continually updated as published data become available. Prior to this, three major updates have been published (Worley and Douglass 1984, "Washington Visual Double Star Catalog, 1984.0", U.S. Naval Observatory, Washington; Worley and Douglass 1997A&AS..125..523W, Cat. I/237; Mason, Wycoff, Hartkopf, Douglass and Worley 2001AJ....122.3466M; and Mason et al. 2006.5). The Washington Double Star Catalog (WDS) has seen numerous changes since the last major release of the catalog. The application of many techniques and considerable industry over the past few years has yielded significant gains in both the number of systems and the number of measures. Is is maintained by the US Naval Observatory, and represents the world's principal database of astrometric double and multiple star information. The WDS contains positions (J2000), discoverer designations, epochs, position angles, separations, magnitudes, spectral types, proper motions, and, when available, Durchmusterung numbers and notes for the components of the systems. (3 data files).

VizieR Online Data Catalog: The Washington Visual Double Star Catalog (Mason+ 2001-2013)

NASA Astrophysics Data System (ADS)

Mason, B. D.; Wycoff, G. L.; Hartkopf, W. I.; Douglass, G. G.; Worley, C. E.

2013-11-01

The Washington Visual Double Star Catalog (WDS) is the successor to the Index Catalogue of Visual Double Stars, 1961.0 (IDS; Jeffers and van den Bos, Publ. Lick Obs. 21). Three earlier double star catalogs in XXth century, those by Burnham (BDS, 1906, "General Catalogue of Double Stars within 121 degrees of the North Pole", Carnegie Institution of Washington), Innes (SDS, 1927, "Southern Double Star Catalogue -19 to -90 degrees", Union Observatory, Johannesburg, South Africa), and Aitken (ADS, 1932 "New General Catalogue of Double Stars within 121 degrees of the North Pole", Carnegie Institution of Washington), each covered only a portion of the sky. Both the IDS and the WDS cover the entire sky, and the WDS is intended to contain all known visual double stars for which at least one differential measure has been published. The WDS is continually updated as published data become available. Prior to this, three major updates have been published (Worley and Douglass 1984, "Washington Visual Double Star Catalog, 1984.0", U.S. Naval Observatory, Washington; Worley and Douglass 1997A&AS..125..523W, Cat. I/237; Mason, Wycoff, Hartkopf, Douglass and Worley 2001AJ....122.3466M; and Mason et al. 2006.5). The Washington Double Star Catalog (WDS) has seen numerous changes since the last major release of the catalog. The application of many techniques and considerable industry over the past few years has yielded significant gains in both the number of systems and the number of measures. Is is maintained by the US Naval Observatory, and represents the world's principal database of astrometric double and multiple star information. The WDS contains positions (J2000), discoverer designations, epochs, position angles, separations, magnitudes, spectral types, proper motions, and, when available, Durchmusterung numbers and notes for the components of the systems. (3 data files).

VizieR Online Data Catalog: The Washington Visual Double Star Catalog (Mason+ 2001-2014)

NASA Astrophysics Data System (ADS)

Mason, B. D.; Wycoff, G. L.; Hartkopf, W. I.; Douglass, G. G.; Worley, C. E.

2017-11-01

The Washington Visual Double Star Catalog (WDS) is the successor to the Index Catalogue of Visual Double Stars, 1961.0 (IDS; Jeffers and van den Bos, Publ. Lick Obs. 21). Three earlier double star catalogs in XXth century, those by Burnham (BDS, 1906, "General Catalogue of Double Stars within 121 degrees of the North Pole", Carnegie Institution of Washington), Innes (SDS, 1927, "Southern Double Star Catalogue -19 to -90 degrees", Union Observatory, Johannesburg, South Africa), and Aitken (ADS, 1932 "New General Catalogue of Double Stars within 121 degrees of the North Pole", Carnegie Institution of Washington), each covered only a portion of the sky. Both the IDS and the WDS cover the entire sky, and the WDS is intended to contain all known visual double stars for which at least one differential measure has been published. The WDS is continually updated as published data become available. Prior to this, three major updates have been published (Worley and Douglass 1984, "Washington Visual Double Star Catalog, 1984.0", U.S. Naval Observatory, Washington; Worley and Douglass 1997A&AS..125..523W, Cat. I/237; Mason, Wycoff, Hartkopf, Douglass and Worley 2001AJ....122.3466M; and Mason et al. 2006.5). The Washington Double Star Catalog (WDS) has seen numerous changes since the last major release of the catalog. The application of many techniques and considerable industry over the past few years has yielded significant gains in both the number of systems and the number of measures. Is is maintained by the US Naval Observatory, and represents the world's principal database of astrometric double and multiple star information. The WDS contains positions (J2000), discoverer designations, epochs, position angles, separations, magnitudes, spectral types, proper motions, and, when available, Durchmusterung numbers and notes for the components of the systems. (3 data files).

VizieR Online Data Catalog: The Washington Visual Double Star Catalog (Mason+ 2001-2014)

NASA Astrophysics Data System (ADS)

Mason, B. D.; Wycoff, G. L.; Hartkopf, W. I.; Douglass, G. G.; Worley, C. E.

2018-06-01

The Washington Visual Double Star Catalog (WDS) is the successor to the Index Catalogue of Visual Double Stars, 1961.0 (IDS; Jeffers and van den Bos, Publ. Lick Obs. 21). Three earlier double star catalogs in XXth century, those by Burnham (BDS, 1906, "General Catalogue of Double Stars within 121 degrees of the North Pole", Carnegie Institution of Washington), Innes (SDS, 1927, "Southern Double Star Catalogue -19 to -90 degrees", Union Observatory, Johannesburg, South Africa), and Aitken (ADS, 1932 "New General Catalogue of Double Stars within 121 degrees of the North Pole", Carnegie Institution of Washington), each covered only a portion of the sky. Both the IDS and the WDS cover the entire sky, and the WDS is intended to contain all known visual double stars for which at least one differential measure has been published. The WDS is continually updated as published data become available. Prior to this, three major updates have been published (Worley and Douglass 1984, "Washington Visual Double Star Catalog, 1984.0", U.S. Naval Observatory, Washington; Worley and Douglass 1997A&AS..125..523W, Cat. I/237; Mason, Wycoff, Hartkopf, Douglass and Worley 2001AJ....122.3466M; and Mason et al. 2006.5). The Washington Double Star Catalog (WDS) has seen numerous changes since the last major release of the catalog. The application of many techniques and considerable industry over the past few years has yielded significant gains in both the number of systems and the number of measures. Is is maintained by the US Naval Observatory, and represents the world's principal database of astrometric double and multiple star information. The WDS contains positions (J2000), discoverer designations, epochs, position angles, separations, magnitudes, spectral types, proper motions, and, when available, Durchmusterung numbers and notes for the components of the systems. (3 data files).

The Influence of Multiple Nested Layer Waviness on the Compression Strength of Double Nested Wave Formations in a Carbon Fiber Composite Laminate

NASA Astrophysics Data System (ADS)

Khan, Z. M.; Adams, D. O.; Anas, S.

2016-01-01

As advanced composite materials having superior physical and mechanical properties are being developed, the optimization of their processing techniques is eagerly sought. One of the most common defects arising during processing of structural composites is layer waviness. The layer waviness is more pronounced in thick-section flat and cylindrical laminates, which are extensively used in large wind turbine blades, submersibles, and space platforms. The layer waviness undulates the entire layer of a multidirectional laminate in the throughthe-thickness direction, leading to a gross deterioration of its compressive strength. This research investigates the influence of multiple layer waviness in a double nest formation on the compression strength of a composite laminate. Different wave fractions of wavy 0° layers were fabricated in an IM/8551-7 carbon-epoxy composite laminate on a steel mold by using a single-step fabrication procedure. The test laminates were cured on a heated press according to the specific curing cycle of epoxy. Their static compression testing was performed using a NASA short block compression fixture on an MTS servohydraulic machine. The purpose of these tests was to determine the effects of multiple layer wave regions on the compression strength of the composite laminate. The experimental and analytical results obtained revealed that the reduction in the compression strength of composite laminate was constant after the fraction of the wavy 0° layers exceeded 35%. This analysis indicated that the percentage of the 0° wavy layer may be used to estimate the reduction in the compression strength of a double nested wave formation in a composite laminate.

Factorization of differential expansion for non-rectangular representations

NASA Astrophysics Data System (ADS)

Morozov, A.

2018-04-01

Factorization of the differential expansion (DE) coefficients for colored HOMFLY-PT polynomials of antiparallel double braids, originally discovered for rectangular representations R, in the case of rectangular representations R, is extended to the first non-rectangular representations R = [2, 1] and R = [3, 1]. This increases chances that such factorization will take place for generic R, thus fixing the shape of the DE. We illustrate the power of the method by conjecturing the DE-induced expression for double-braid polynomials for all R = [r, 1]. In variance with the rectangular case, the knowledge for double braids is not fully sufficient to deduce the exclusive Racah matrix S¯ — the entries in the sectors with nontrivial multiplicities sum up and remain unseparated. Still, a considerable piece of the matrix is extracted directly and its other elements can be found by solving the unitarity constraints.

Low-frequency switching in a transistor amplifier.

PubMed

Carroll, T L

2003-04-01

It is known from extensive work with the diode resonator that the nonlinear properties of a P-N junction can lead to period doubling, chaos, and other complicated behaviors in a driven circuit. There has been very little work on what happens when more than one P-N junction is present. In this work, the first step towards multiple P-N junction circuits is taken by doing both experiments and simulations with a single-transistor amplifier using a bipolar transistor. Period doubling and chaos are seen when the amplifier is driven with signals between 100 kHz and 1 MHz, and they coincide with a very low frequency switching between different period doubled (or chaotic) wave forms. The switching frequencies are between 5 and 10 Hz. The switching behavior was confirmed in a simplified model of the transistor amplifier.

Double-Balloon-Assisted n-Butyl-2-Cyanoacrylate Embolization of Intrahepatic Arterioportal Shunt Prior to Chemoembolization of Hepatocellular Carcinoma

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

Takao, Hidemasa, E-mail: takaoh-tky@umin.ac.jp; Shibata, Eisuke; Ohtomo, Kuni

A case of multiple hepatocellular carcinomas with a severe intrahepatic arterioportal shunt that was successfully embolized with n-butyl-2-cyanoacrylate with coaxial double-balloon occlusion prior to transcatheter arterial chemoembolization is presented. A proximal balloon positioned at the proper hepatic artery was used for flow control, and a coaxial microballoon, positioned in the closest of three arterial feeding branches to the arterioportal shunt, was used to control the delivery of n-butyl-2-cyanoacrylate. This coaxial double-balloon technique can prevent proximal embolization and distal migration of n-butyl-2-cyanoacrylate and enable precise control of the distribution of n-butyl-2-cyanoacrylate. It could also be applicable to n-butyl-2-cyanoacrylate embolization for othermore » than intrahepatic arterioportal shunt.« less

REC-1 and HIM-5 distribute meiotic crossovers and function redundantly in meiotic double-strand break formation in Caenorhabditis elegans

PubMed Central

Chung, George; Rose, Ann M.; Petalcorin, Mark I.R.; Martin, Julie S.; Kessler, Zebulin; Sanchez-Pulido, Luis; Ponting, Chris P.; Yanowitz, Judith L.; Boulton, Simon J.

2015-01-01

The Caenorhabditis elegans gene rec-1 was the first genetic locus identified in metazoa to affect the distribution of meiotic crossovers along the chromosome. We report that rec-1 encodes a distant paralog of HIM-5, which was discovered by whole-genome sequencing and confirmed by multiple genome-edited alleles. REC-1 is phosphorylated by cyclin-dependent kinase (CDK) in vitro, and mutation of the CDK consensus sites in REC-1 compromises meiotic crossover distribution in vivo. Unexpectedly, rec-1; him-5 double mutants are synthetic-lethal due to a defect in meiotic double-strand break formation. Thus, we uncovered an unexpected robustness to meiotic DSB formation and crossover positioning that is executed by HIM-5 and REC-1 and regulated by phosphorylation. PMID:26385965

Double Aneuploidy Detected by Cell-Free DNA Testing and Confirmed by Fetal Tissue Analysis.

PubMed

Echague, Charlene G; Petersen, Scott M

2016-06-01

Double aneuploidies account for 0.21-2.8% of spontaneous abortions resulting from chromosomal abnormalities. Rarely, cell-free DNA testing detects multiple aneuploidies; however, to discern among maternal, placental, and fetal origin, further evaluation is required. A 49-year-old woman, gravida 5 para 0, underwent cell-free DNA testing at 11 4/7 weeks of gestation, which revealed a fetus that was high risk for trisomies 18 and 21. On ultrasonography at 14 weeks of gestation, she was diagnosed with a missed abortion and underwent surgical management. Fetal and placental tissues were sent for analysis and were positive for trisomies 18 and 21, confirming the results of cell-free DNA testing. Our case highlights the ability of cell-free DNA testing to recognize a double aneuploidy confirmed by fetal tissue analysis.

Intersections of discrimination due to unemployment and mental health problems: the role of double stigma for job- and help-seeking behaviors.

PubMed

Staiger, Tobias; Waldmann, Tamara; Oexle, Nathalie; Wigand, Moritz; Rüsch, Nicolas

2018-05-21

The everyday lives of unemployed people with mental health problems can be affected by multiple discrimination, but studies about double stigma-an overlap of identities and experiences of discrimination-in this group are lacking. We therefore studied multiple discrimination among unemployed people with mental health problems and its consequences for job- and help-seeking behaviors. Everyday discrimination and attributions of discrimination to unemployment and/or to mental health problems were examined among 301 unemployed individuals with mental health problems. Job search self-efficacy, barriers to care, and perceived need for treatment were compared among four subgroups, depending on attributions of experienced discrimination to unemployment and to mental health problems (group i); neither to unemployment nor to mental health problems (group ii); mainly to unemployment (group iii); or mainly to mental health problems (group iv). In multiple regressions among all participants, higher levels of discrimination predicted reduced job search self-efficacy and higher barriers to care; and attributions of discrimination to unemployment were associated with increased barriers to care. In ANOVAs for subgroup comparisons, group i participants, who attributed discrimination to both unemployment and mental health problems, reported lower job search self-efficacy, more perceived stigma-related barriers to care and more need for treatment than group iii participants, as well as more stigma-related barriers to care than group iv. Multiple discrimination may affect job search and help-seeking among unemployed individuals with mental health problems. Interventions to reduce public stigma and to improve coping with multiple discrimination for this group should be developed.

Combining Formal and Informal Caregiving Roles: The Psychosocial Implications of Double- and Triple-Duty Care.

PubMed

DePasquale, Nicole; Davis, Kelly D; Zarit, Steven H; Moen, Phyllis; Hammer, Leslie B; Almeida, David M

2016-03-01

Women who combine formal and informal caregiving roles represent a unique, understudied population. In the literature, healthcare employees who simultaneously provide unpaid elder care at home have been referred to as double-duty caregivers. The present study broadens this perspective by examining the psychosocial implications of double-duty child care (child care only), double-duty elder care (elder care only), and triple-duty care (both child care and elder care or "sandwiched" care). Drawing from the Work, Family, and Health Study, we focus on a large sample of women working in nursing homes in the United States (n = 1,399). We use multiple regression analysis and analysis of covariance tests to examine a range of psychosocial implications associated with double- and triple-duty care. Compared with nonfamily caregivers, double-duty child caregivers indicated greater family-to-work conflict and poorer partner relationship quality. Double-duty elder caregivers reported more family-to-work conflict, perceived stress, and psychological distress, whereas triple-duty caregivers indicated poorer psychosocial functioning overall. Relative to their counterparts without family caregiving roles, women with combined caregiving roles reported poorer psychosocial well-being. Additional research on women with combined caregiving roles, especially triple-duty caregivers, should be a priority amidst an aging population, older workforce, and growing number of working caregivers. © The Author 2014. 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.

Costs of achieving live birth from assisted reproductive technology: a comparison of sequential single and double embryo transfer approaches.

PubMed

Crawford, Sara; Boulet, Sheree L; Mneimneh, Allison S; Perkins, Kiran M; Jamieson, Denise J; Zhang, Yujia; Kissin, Dmitry M

2016-02-01

To assess treatment and pregnancy/infant-associated medical costs and birth outcomes for assisted reproductive technology (ART) cycles in a subset of patients using elective double embryo (ET) and to project the difference in costs and outcomes had the cycles instead been sequential single ETs (fresh followed by frozen if the fresh ET did not result in live birth). Retrospective cohort study using 2012 and 2013 data from the National ART Surveillance System. Infertility treatment centers. Fresh, autologous double ETs performed in 2012 among ART patients younger than 35 years of age with no prior ART use who cryopreserved at least one embryo. Sequential single and double ETs. Actual live birth rates and estimated ART treatment and pregnancy/infant-associated medical costs for double ET cycles started in 2012 and projected ART treatment and pregnancy/infant-associated medical costs if the double ET cycles had been performed as sequential single ETs. The estimated total ART treatment and pregnancy/infant-associated medical costs were $580.9 million for 10,001 double ETs started in 2012. If performed as sequential single ETs, estimated costs would have decreased by $195.0 million to $386.0 million, and live birth rates would have increased from 57.7%-68.0%. Sequential single ETs, when clinically appropriate, can reduce total ART treatment and pregnancy/infant-associated medical costs by reducing multiple births without lowering live birth rates. Published by Elsevier Inc.

Electromagnetic field scattering by a triangular aperture.

PubMed

Harrison, R E; Hyman, E

1979-03-15

The multiple Laplace transform has been applied to analysis and computation of scattering by a double triangular aperture. Results are obtained which match far-field intensity distributions observed in experiments. Arbitrary polarization components, as well as in-phase and quadrature-phase components, may be determined, in the transform domain, as a continuous function of distance from near to far-field for any orientation, aperture, and transformable waveform. Numerical results are obtained by application of numerical multiple inversions of the fully transformed solution.

Surface-Finish Measurement with Interference Microscopes,

DTIC Science & Technology

1977-02-01

Microscope 17 Multiple-Beam Interference Microscope .. 25 Fringes of Equal Chromatic Order 27 Nomarski Polarization-Contrast Technique 33...characteristics of each instrument: the double and multiple-beam interferometer, the FECO fringe interferometer, and the Nomarski polarization contrast...328X Beam Reichert 8X 0.15 2.22 87 33X Nomarski 16X 0.25 1.33 52 55X 203X Technique 32X 0.40 0.83 33 87X 395X 45 X 0.65 0.51 20 142X 567 X 80X

Iron-Isotopic Fractionation Studies Using Multiple Collector Inductively Coupled Plasma Mass Spectrometry

NASA Technical Reports Server (NTRS)

Anbar, A. D.; Zhang, C.; Barling, J.; Roe, J. E.; Nealson, K. H.

1999-01-01

The importance of Fe biogeochemistry has stimulated interest in Fe isotope fractionation. Recent studies using thermal ionization mass spectrometry (TIMS) and a "double spike" demonstrate the existence of biogenic Fe isotope effects. Here, we assess the utility of multiple-collector inductively-coupled plasma mass spectrometry(MC-ICP-MS) with a desolvating sample introduction system for Fe isotope studies, and present data on Fe biominerals produced by a thermophilic bacterium. Additional information is contained in the original extended abstract.

Low loss InGaAs/InP multiple quantum well waveguides

NASA Astrophysics Data System (ADS)

Koren, U.; Miller, B. I.; Koch, T. L.; Boyd, G. D.; Capik, R. J.

1986-12-01

Double heterostructure planar waveguides with an InGaAs/InP multiple quantum well (MQW) core and InP cladding layers were grown by atmospheric pressure metalorganic chemical vapor deposition. Ridge waveguides had a low propagation loss of 0.8 dB/cm for 1.52 micron input light. The indices of refraction for the guided TE and TM modes have been measured and the bulk dispersion curves of the MQW material for the 1.46-1.55 micron wavelength region were derived.

Processing speed and working memory training in multiple sclerosis: a double-blind randomized controlled pilot study.

PubMed

Hancock, Laura M; Bruce, Jared M; Bruce, Amanda S; Lynch, Sharon G

2015-01-01

Between 40-65% of multiple sclerosis patients experience cognitive deficits, with processing speed and working memory most commonly affected. This pilot study investigated the effect of computerized cognitive training focused on improving processing speed and working memory. Participants were randomized into either an active or a sham training group and engaged in six weeks of training. The active training group improved on a measure of processing speed and attention following cognitive training, and data trended toward significance on measures of other domains. Results provide preliminary evidence that cognitive training with multiple sclerosis patients may produce moderate improvement in select areas of cognitive functioning.

Multiple congenital PSS in a dog: case report and literature review.

PubMed

Leeman, Jessica J; Kim, Stanley E; Reese, David J; Risselada, Marije; Ellison, Gary W

2013-01-01

A 4 yr old spayed female mixed-breed dog presented with a 2 yr history of recurring increases in liver enzymes. Two congenital portosystemic shunts (PSSs) were identified using computed tomography (CT) angiography, which included a portoazygous and portorenal extrahepatic shunt. Double right renal veins were also identified. The shunts were successfully identified and attenuated with cellophane banding. Multiple congenital PSS is a rare phenomenon, but should be considered during exploratory laparotomy for PSS and in dogs with poor response to surgical attenuation of a single PSS. CT proved to be a crucial part of accurate diagnosis and surgical planning for this dog with multiple congenital PSS.

Multi-pinhole SPECT Imaging with Silicon Strip Detectors

PubMed Central

Peterson, Todd E.; Shokouhi, Sepideh; Furenlid, Lars R.; Wilson, Donald W.

2010-01-01

Silicon double-sided strip detectors offer outstanding instrinsic spatial resolution with reasonable detection efficiency for iodine-125 emissions. This spatial resolution allows for multiple-pinhole imaging at low magnification, minimizing the problem of multiplexing. We have conducted imaging studies using a prototype system that utilizes a detector of 300-micrometer thickness and 50-micrometer strip pitch together with a 23-pinhole collimator. These studies include an investigation of the synthetic-collimator imaging approach, which combines multiple-pinhole projections acquired at multiple magnifications to obtain tomographic reconstructions from limited-angle data using the ML-EM algorithm. Sub-millimeter spatial resolution was obtained, demonstrating the basic validity of this approach. PMID:20953300

CCD Astrometric Measurements of WDS 08167+4053 Using the iTelescope Network

NASA Astrophysics Data System (ADS)

Riley, Bill; Li, Dewei; Li, Junyao; Dennis, Aren; Boyce, Grady; Boyce, Pat

2016-10-01

Separations and position angle astrometric measurements were made of the multiple star system WDS 08167+4053 AB, AC, and BC components. Our measurements compared favorably with historical measurements from the United States Naval Observatory Washington Double Star Catalog, confirming the trend.

Derivatized versions of ligase enzymes for constructing DNA sequences

DOEpatents

Mariella, Jr., Raymond P.; Christian, Allen T [Tracy, CA; Tucker, James D [Novi, MN; Dzenitis, John M [Livermore, CA; Papavasiliou, Alexandros P [Oakland, CA

2006-08-15

A method of making very long, double-stranded synthetic poly-nucleotides. A multiplicity of short oligonucleotides is provided. The short oligonucleotides are sequentially hybridized to each other. Enzymatic ligation of the oligonucleotides provides a contiguous piece of PCR-ready DNA of predetermined sequence.

Double-null divertor configuration discharge and disruptive heat flux simulation using TSC on EAST

NASA Astrophysics Data System (ADS)

Bo, SHI; Jinhong, YANG; Cheng, YANG; Desheng, CHENG; Hui, WANG; Hui, ZHANG; Haifei, DENG; Junli, QI; Xianzu, GONG; Weihua, WANG

2018-07-01

The tokamak simulation code (TSC) is employed to simulate the complete evolution of a disruptive discharge in the experimental advanced superconducting tokamak. The multiplication factor of the anomalous transport coefficient was adjusted to model the major disruptive discharge with double-null divertor configuration based on shot 61 916. The real-time feed-back control system for the plasma displacement was employed. Modeling results of the evolution of the poloidal field coil currents, the plasma current, the major radius, the plasma configuration all show agreement with experimental measurements. Results from the simulation show that during disruption, heat flux about 8 MW m‑2 flows to the upper divertor target plate and about 6 MW m‑2 flows to the lower divertor target plate. Computations predict that different amounts of heat fluxes on the divertor target plate could result by adjusting the multiplication factor of the anomalous transport coefficient. This shows that TSC has high flexibility and predictability.

Video multiple watermarking technique based on image interlacing using DWT.

PubMed

Ibrahim, Mohamed M; Abdel Kader, Neamat S; Zorkany, M

2014-01-01

Digital watermarking is one of the important techniques to secure digital media files in the domains of data authentication and copyright protection. In the nonblind watermarking systems, the need of the original host file in the watermark recovery operation makes an overhead over the system resources, doubles memory capacity, and doubles communications bandwidth. In this paper, a robust video multiple watermarking technique is proposed to solve this problem. This technique is based on image interlacing. In this technique, three-level discrete wavelet transform (DWT) is used as a watermark embedding/extracting domain, Arnold transform is used as a watermark encryption/decryption method, and different types of media (gray image, color image, and video) are used as watermarks. The robustness of this technique is tested by applying different types of attacks such as: geometric, noising, format-compression, and image-processing attacks. The simulation results show the effectiveness and good performance of the proposed technique in saving system resources, memory capacity, and communications bandwidth.

A Solution to Separation and Multicollinearity in Multiple Logistic Regression

PubMed Central

Shen, Jianzhao; Gao, Sujuan

2010-01-01

In dementia screening tests, item selection for shortening an existing screening test can be achieved using multiple logistic regression. However, maximum likelihood estimates for such logistic regression models often experience serious bias or even non-existence because of separation and multicollinearity problems resulting from a large number of highly correlated items. Firth (1993, Biometrika, 80(1), 27–38) proposed a penalized likelihood estimator for generalized linear models and it was shown to reduce bias and the non-existence problems. The ridge regression has been used in logistic regression to stabilize the estimates in cases of multicollinearity. However, neither solves the problems for each other. In this paper, we propose a double penalized maximum likelihood estimator combining Firth’s penalized likelihood equation with a ridge parameter. We present a simulation study evaluating the empirical performance of the double penalized likelihood estimator in small to moderate sample sizes. We demonstrate the proposed approach using a current screening data from a community-based dementia study. PMID:20376286

A Solution to Separation and Multicollinearity in Multiple Logistic Regression.

PubMed

Shen, Jianzhao; Gao, Sujuan

2008-10-01

In dementia screening tests, item selection for shortening an existing screening test can be achieved using multiple logistic regression. However, maximum likelihood estimates for such logistic regression models often experience serious bias or even non-existence because of separation and multicollinearity problems resulting from a large number of highly correlated items. Firth (1993, Biometrika, 80(1), 27-38) proposed a penalized likelihood estimator for generalized linear models and it was shown to reduce bias and the non-existence problems. The ridge regression has been used in logistic regression to stabilize the estimates in cases of multicollinearity. However, neither solves the problems for each other. In this paper, we propose a double penalized maximum likelihood estimator combining Firth's penalized likelihood equation with a ridge parameter. We present a simulation study evaluating the empirical performance of the double penalized likelihood estimator in small to moderate sample sizes. We demonstrate the proposed approach using a current screening data from a community-based dementia study.

Fractured Identity: A Framework for Understanding Young Asian American Women's Self-harm and Suicidal Behaviors.

PubMed

Hahm, Hyeouk Chris; Gonyea, Judith G; Chiao, Christine; Koritsanszky, Luca Anna

2014-01-01

Despite the high suicide rate among young Asian American women, the reasons for this phenomenon remain unclear. This qualitative study explored the family experiences of 16 young Asian American women who are children of immigrants and report a history of self-harm and/or suicidal behaviors. Our findings suggest that the participants experienced multiple types of "disempowering parenting styles" that are characterized as: abusive, burdening, culturally disjointed, disengaged, and gender-prescriptive parenting. Tied to these family dynamics is the double bind that participants suffer. Exposed to multiple types of negative parenting, the women felt paralyzed by opposing forces, caught between a deep desire to satisfy their parents' expectations as well as societal expectations and to simultaneously rebel against the image of "the perfect Asian woman." Torn by the double bind, these women developed a "fractured identity," which led to the use of "unsafe coping" strategies. Trapped in a "web of pain," the young women suffered alone and engaged in self-harm and suicidal behaviors.

Multiple secondary islands formation in nonlinear evolution of double tearing mode simulations

NASA Astrophysics Data System (ADS)

Guo, W.; Ma, J.; Yu, Z.

2017-03-01

A new numerical code solving the conservative perturbed resistive magnetohydrodynamic (MHD) model is developed. Numerical tests of the ideal Kelvin-Helmholtz instability and the resistive double tearing mode (DTM) show its capability in solving linear and nonlinear MHD instabilities. The nonlinear DTM evolution in 2D geometry is numerically investigated with low guiding field B z 0 , short half-distance y 0 between the equilibrium current sheets, and small resistivity η. The interaction of islands on the two initial current sheets may generate an unstable flow driven current sheet with a high length-to-thickness aspect ratio (α), and multiple secondary islands can form. In general, the length-to-thickness aspect ratio α and the number of secondary islands increase with decreasing guide field B z 0 , decreasing half-distance y 0 , and increasing Lundquist number of the flow driven current sheet S L although the dependence may be non-monotonic. The reconnection rate dependence on S L , B z 0 , and y 0 is also investigated.

eIF4E/Fmr1 double mutant mice display cognitive impairment in addition to ASD-like behaviors.

PubMed

Huynh, Thu N; Shah, Manan; Koo, So Yeon; Faraud, Kirsten S; Santini, Emanuela; Klann, Eric

2015-11-01

Autism spectrum disorder (ASD) is a group of heritable disorders with complex and unclear etiology. Classic ASD symptoms include social interaction and communication deficits as well as restricted, repetitive behaviors. In addition, ASD is often comorbid with intellectual disability. Fragile X syndrome (FXS) is the leading genetic cause of ASD, and is the most commonly inherited form of intellectual disability. Several mouse models of ASD and FXS exist, however the intellectual disability observed in ASD patients is not well modeled in mice. Using the Fmr1 knockout mouse and the eIF4E transgenic mouse, two previously characterized mouse models of fragile X syndrome and ASD, respectively, we generated the eIF4E/Fmr1 double mutant mouse. Our study shows that the eIF4E/Fmr1 double mutant mice display classic ASD behaviors, as well as cognitive dysfunction. Importantly, the learning impairments displayed by the double mutant mice spanned multiple cognitive tasks. Moreover, the eIF4E/Fmr1 double mutant mice display increased levels of basal protein synthesis. The results of our study suggest that the eIF4E/Fmr1 double mutant mouse may be a reliable model to study cognitive dysfunction in the context of ASD. Copyright © 2015 Elsevier Inc. All rights reserved.

Long-term safety and efficacy of dalfampridine for walking impairment in patients with multiple sclerosis: Results of open-label extensions of two Phase 3 clinical trials

PubMed Central

Goodman, Andrew D; Bethoux, Francois; Brown, Theodore R; Schapiro, Randall T; Cohen, Ron; Marinucci, Lawrence N; Henney, Herbert R

2015-01-01

Background: In Phase 3 double-blind trials (MS-F203 and MS-F204), dalfampridine extended release tablets 10 mg twice daily (dalfampridine-ER; prolonged-release fampridine in Europe; fampridine modified or sustained release elsewhere) improved walking speed relative to placebo in patients with multiple sclerosis (MS). Objectives: Evaluation of long-term safety and efficacy of dalfampridine-ER in open-label extensions (MS-F203EXT, MS-F204EXT). Methods: Patients received dalfampridine-ER 10 mg twice daily; and had Timed 25-Foot Walk (T25FW) assessments at 2, 14 and 26 weeks, and then every 6 months. Subjects were categorized as dalfampridine-ER responders or non-responders, based on their treatment response in the double-blind parent trials that assessed T25FW. Results: We had 269 patients enter MS-F203EXT and 154 patients complete it; for a maximum exposure of 5 years. We had 214 patients enter MS-F204EXT and 146 complete it; for a maximum exposure of 3.3 years. No new safety signals emerged and dalfampridine-ER tolerability was consistent with the double-blind phase. Improvements in walking speed were lost after dalfampridine-ER was discontinued in the parent trial, but returned by the 2-week assessment after re-initiation of the drug. Throughout the extensions, mean improvement in walking speed declined, but remained improved, among the double-blind responders as compared with non-responders. Conclusions: The dalfamipridine-ER safety profile was consistent with the parent trials. Although walking speed decreased over time, dalfampridine-ER responders continued to show improved walking speed, which was sustained compared with non-responders. PMID:25583832

The Fanconi anemia associated protein FAAP24 uses two substrate specific binding surfaces for DNA recognition

PubMed Central

Wienk, Hans; Slootweg, Jack C.; Speerstra, Sietske; Kaptein, Robert; Boelens, Rolf; Folkers, Gert E.

2013-01-01

To maintain the integrity of the genome, multiple DNA repair systems exist to repair damaged DNA. Recognition of altered DNA, including bulky adducts, pyrimidine dimers and interstrand crosslinks (ICL), partially depends on proteins containing helix-hairpin-helix (HhH) domains. To understand how ICL is specifically recognized by the Fanconi anemia proteins FANCM and FAAP24, we determined the structure of the HhH domain of FAAP24. Although it resembles other HhH domains, the FAAP24 domain contains a canonical hairpin motif followed by distorted motif. The HhH domain can bind various DNA substrates; using nuclear magnetic resonance titration experiments, we demonstrate that the canonical HhH motif is required for double-stranded DNA (dsDNA) binding, whereas the unstructured N-terminus can interact with single-stranded DNA. Both DNA binding surfaces are used for binding to ICL-like single/double-strand junction-containing DNA substrates. A structural model for FAAP24 bound to dsDNA has been made based on homology with the translesion polymerase iota. Site-directed mutagenesis, sequence conservation and charge distribution support the dsDNA-binding model. Analogous to other HhH domain-containing proteins, we suggest that multiple FAAP24 regions together contribute to binding to single/double-strand junction, which could contribute to specificity in ICL DNA recognition. PMID:23661679

Double-strand break repair-adox: Restoration of suppressed double-strand break repair during mitosis induces genomic instability

PubMed Central

Terasawa, Masahiro; Shinohara, Akira; Shinohara, Miki

2014-01-01

Double-strand breaks (DSBs) are one of the severest types of DNA damage. Unrepaired DSBs easily induce cell death and chromosome aberrations. To maintain genomic stability, cells have checkpoint and DSB repair systems to respond to DNA damage throughout most of the cell cycle. The failure of this process often results in apoptosis or genomic instability, such as aneuploidy, deletion, or translocation. Therefore, DSB repair is essential for maintenance of genomic stability. During mitosis, however, cells seem to suppress the DNA damage response and proceed to the next G1 phase, even if there are unrepaired DSBs. The biological significance of this suppression is not known. In this review, we summarize recent studies of mitotic DSB repair and discuss the mechanisms of suppression of DSB repair during mitosis. DSB repair, which maintains genomic integrity in other phases of the cell cycle, is rather toxic to cells during mitosis, often resulting in chromosome missegregation and aberration. Cells have multiple safeguards to prevent genomic instability during mitosis: inhibition of 53BP1 or BRCA1 localization to DSB sites, which is important to promote non-homologous end joining or homologous recombination, respectively, and also modulation of the non-homologous end joining core complex to inhibit DSB repair. We discuss how DSBs during mitosis are toxic and the multiple safeguard systems that suppress genomic instability. PMID:25287622

Economic evaluations of single- versus double-embryo transfer in IVF.

PubMed

Fiddelers, A A A; Severens, J L; Dirksen, C D; Dumoulin, J C M; Land, J A; Evers, J L H

2007-01-01

Multiple pregnancies lead to complications and induce high costs. The most successful way to decrease multiple pregnancies in IVF is to transfer only one embryo, which might reduce the efficacy of treatment. The objective of this review is to determine which embryo-transfer policy is most cost-effective: elective single-embryo transfer (eSET) or double-embryo transfer (DET). Several databases were searched for (cost* or econ*) and (single embryo* or double embryo* or one embryo* or two embryo* or elect* embryo or multip* embryo*). On the basis of five exclusion criteria, titles and abstracts were screened by two individual reviewers. The remaining papers were read for further selection, and data were extracted from the selected studies. A total of 496 titles were identified through the searches and resulted in the selection of one observational study and three randomized studies. Study characteristics, total costs and probability of live births were extracted. Besides this, cost-effectiveness and incremental cost-effectiveness were derived. It can be concluded that DET is the most expensive strategy. DET is also most effective if performed in one fresh cycle. eSET is only preferred from a cost-effectiveness point of view when performed in good prognosis patients and when frozen/thawed cycles are included. If frozen/thawed cycles are excluded, the choice between eSET and DET depends on how much society is willing to pay for one extra successful pregnancy.

Social Choice in a Computer-Assisted Simulation

ERIC Educational Resources Information Center

Thavikulwat, Precha

2009-01-01

Pursuing a line of inquiry suggested by Crookall, Martin, Saunders, and Coote, the author applied, within the framework of design science, an optimal-design approach to incorporate into a computer-assisted simulation two innovative social choice processes: the multiple period double auction and continuous voting. Expectations that the…

Laser Induced Fluorescence Studies of Electrostatic Double Layers in an Expanding Helicon Plasma

NASA Astrophysics Data System (ADS)

Carr, Jerry, Jr.

We report the first evidence of a laboratory double layer (DL) collapsing in the presence of an instability studied by Chakraborty Thakur et al. 1 with the use of time resolved laser induced fluorescence (LIF) studies. Higher time resolution studies then provided the first statistically validated proof of the correlation between the ion acoustic instability and a DL. Time-frequency analysis in the form of time resolved cross power spectra and continuous wavelet transforms were used to provide insight into beam formation. The implications of this work is that in the creation of strong DLs in expanding plasmas for plasma propulsion or other applications may be self-limited through instability growth. Over the past decade, experimental and theoretical studies have demonstrated the formation of stable, electrostatic, current-free double layers (CFDLs) in plasmas with a strong density gradient; typically a result of a divergent magnetic field. In this work, we present evidence for the formation of multiple double layers within a single divergent magnetic field structure. Downstream of the divergent magnetic field, multiple accelerated ion populations are observed through laser induced fluorescence measurements of the ion velocity distribution function. The formation of the multiple double layer structure is a strong function of the neutral gas pressure in the experiment. The similarity of the accelerated ion populations observed in these laboratory experiments to ion populations observed in reconnection outflow regions in the magnetosphere and in numerical simulations is also described. If ion energization during magnetic reconnection also results solely from acceleration in electric fields, these observations imply a prediction that the ion heating, i.e., the broadening of ion velocity distribution functions, reported in magnetic reconnection experiments is more accurately described by a superposition of differently accelerated ion populations. Therefore, the ion gheatingh rate during reconnection should scale as the square root of the cube of the charge per unit mass (q3/m)1/2 for ions with varying charge-to-mass ratios. A new RFEA probe was benchmarked on the low pressure CFDL plasmas produced in WVU HELIX-LEIA. This work was the result of collaboration between the University of Tromso (UiT) and WVU. LIF was used to confirm the RFEAs ability to detect a beam when one was present. The RFEA was also able to detect the presence of a beam when LIF techniques were limited by metastable quenching. The probefs limitations in dealing with ion focusing are discussed as well.

Development of a lithium fluoride zinc sulfide based neutron multiplicity counter

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

Cowles, Christian; Behling, Spencer; Baldez, Phoenix

Past 3He shortages led to investigations into replacement options for neutron detectors in systems that previously used 3He-based technologies. The goal of this research was to investigate the feasibility of a full-scale lithium fluoride with silver activated zinc sulfide (LiF/ZnS) based neutron multiplicity counter. The LiF/ZnS based neutron multiplicity counter (LiNMC) was developed based on an iterative process between modeling and experimental measurements. Each active region of the LiNMC contains five sheets of LiF/ZnS sandwiched between six sheets of wavelength shifting plastic to form neutron detection stacks. The wavelength shifted scintillation light was collected by photomultiplier tubes located on eachmore » end of the stacks. Twelve such detector stacks were placed around a sample chamber in a square arrangement with lithiated high density polyethylene blocks in the corners to reflect high energy neutrons and capture low energy neutrons. Preliminary calibration with a 252Cf neutron source showed that the LiNMC was able to achieve 36% neutron detection efficiency (ε) and an 11.7 μs neutron die-away time (τ) for a doubles Figure-of-merit (ε2/ τ) of 109. This is the highest doubles Figure-of-merit performance measured to-date for a 3He-free neutron multiplicity counter system. By the end of this project, the LiNMC’s basic components were integrated into a single laboratory scale system capable of proof-of-concept measurements.« less

An Accelerated Recursive Doubling Algorithm for Block Tridiagonal Systems

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

Seal, Sudip K

2014-01-01

Block tridiagonal systems of linear equations arise in a wide variety of scientific and engineering applications. Recursive doubling algorithm is a well-known prefix computation-based numerical algorithm that requires O(M^3(N/P + log P)) work to compute the solution of a block tridiagonal system with N block rows and block size M on P processors. In real-world applications, solutions of tridiagonal systems are most often sought with multiple, often hundreds and thousands, of different right hand sides but with the same tridiagonal matrix. Here, we show that a recursive doubling algorithm is sub-optimal when computing solutions of block tridiagonal systems with multiplemore » right hand sides and present a novel algorithm, called the accelerated recursive doubling algorithm, that delivers O(R) improvement when solving block tridiagonal systems with R distinct right hand sides. Since R is typically about 100 1000, this improvement translates to very significant speedups in practice. Detailed complexity analyses of the new algorithm with empirical confirmation of runtime improvements are presented. To the best of our knowledge, this algorithm has not been reported before in the literature.« less

Double-label immunofluorescence method for simultaneous detection of adenovirus and herpes simplex virus from the eye.

PubMed

Walpita, P; Darougar, S

1989-07-01

The development and application of a double-label immunofluorescence method which has the potential to screen for single or dual infections from any site, in single shell vial cultures, is described. In this study, a total of 1,141 ocular specimens were inoculated in shell vials, centrifuged at 15,000 X g for 1 h, incubated at 37 degrees C for 48 h, and fixed in methanol at room temperature for 15 min. The virus inclusions were detected by staining with a double-label indirect immunofluorescence procedure using mixtures of appropriate first antibodies, followed by fluorescein- and rhodamine-conjugated second antibodies. Each specimen was also inoculated in parallel by the conventional virus isolation method. The sensitivity and specificity of the double-label shell vial procedure were comparable to those with the conventional method, and the former test took only 48 h to complete. The test offers a rapid and simple single-vial procedure which allows for individual or simultaneous detection of multiple pathogens. It results in savings in time and cost over the conventional virus isolation method and other shell vial procedures.

Using large spectroscopic surveys to test the double degenerate model for Type Ia supernovae

NASA Astrophysics Data System (ADS)

Breedt, E.; Steeghs, D.; Marsh, T. R.; Gentile Fusillo, N. P.; Tremblay, P.-E.; Green, M.; De Pasquale, S.; Hermes, J. J.; Gänsicke, B. T.; Parsons, S. G.; Bours, M. C. P.; Longa-Peña, P.; Rebassa-Mansergas, A.

2017-07-01

An observational constraint on the contribution of double degenerates to Type Ia supernovae requires multiple radial velocity measurements of ideally thousands of white dwarfs. This is because only a small fraction of the double degenerate population is massive enough, with orbital periods short enough, to be considered viable Type Ia progenitors. We show how the radial velocity information available from public surveys such as the Sloan Digital Sky Survey can be used to pre-select targets for variability, leading to a 10-fold reduction in observing time required compared to an unranked or random survey. We carry out Monte Carlo simulations to quantify the detection probability of various types of binaries in the survey and show that this method, even in the most pessimistic case, doubles the survey size of the largest survey to date (the SPY Survey) in less than 15 per cent of the required observing time. Our initial follow-up observations corroborate the method, yielding 15 binaries so far (eight known and seven new), as well as orbital periods for four of the new binaries.

Pharmacokinetics and Safety of Intravenous Murepavadin Infusion in Healthy Adult Subjects Administered Single and Multiple Ascending Doses.

PubMed

Wach, Achim; Dembowsky, Klaus; Dale, Glenn E

2018-04-01

Murepavadin is the first in class of the outer membrane protein-targeting antibiotics (OMPTA) and a pathogen-specific peptidomimetic antibacterial with a novel, nonlytic mechanism of action targeting Pseudomonas aeruginosa Murepavadin is being developed for the treatment of hospital-acquired bacterial pneumonia (HABP) and ventilator-associated bacterial pneumonia (VABP). The pharmacokinetics (PK) and safety of single and multiple doses of murepavadin were investigated in healthy male subjects. Part A of the study was a double-blind, randomized, placebo-controlled, single-ascending-dose investigation in 10 sequential cohorts where each cohort comprised 6 healthy male subjects; 4 subjects were randomized to murepavadin, and 2 subjects were randomized to placebo. Part B was a double-blind, randomized, placebo-controlled, multiple-ascending-dose investigation in 3 sequential cohorts. After a single dose of murepavadin, the geometric mean half-life (2.52 to 5.30 h), the total clearance (80.1 to 114 ml/h/kg), and the volume of distribution (415 to 724 ml/kg) were consistent across dose levels. The pharmacokinetics of the dosing regimens evaluated were dose proportional and linear. Murepavadin was well tolerated, adverse events were transient and generally mild, and no dose-limiting toxicity was identified. Copyright © 2018 American Society for Microbiology.

Folding control in cyclic peptides through N-methylation pattern selection: formation of antiparallel beta-sheet dimers, double reverse turns and supramolecular helices by 3alpha,gamma cyclic peptides.

PubMed

Amorín, Manuel; Castedo, Luis; Granja, Juan R

2008-01-01

Peptide foldamers constitute a growing class of nanomaterials with potential applications in a wide variety of chemical, medical and technological fields. Here we describe the preparation and structural characteristics of a new class of cyclic peptide foldamers (3alpha,gamma-CPs) that, depending on their backbone N-methylation patterns and the medium, can either remain as flat rings that dimerize through arrays of hydrogen bonds of antiparallel beta-sheet type, or can fold into twisted double reverse turns that, in the case of double gamma-turns, associate in nonpolar solvents to form helical supramolecular structures. A 3alpha,gamma-CP consists of a number of multiples of a repeat unit made up of four amino acid residues of alternating chirality: three corresponding to alpha-amino acids and one to a gamma-amino acid (a cis-3-aminocycloalkanecarboxylic acid).

Double stellate tongue reduction: a new method of treatment for macroglossia in patients with Beckwith-wiedemann syndrome.

PubMed

Hettinger, Patrick C; Denny, Arlen D

2011-09-01

Although multiple methods of tongue reduction have been described, recent literature suggests that the central reductions may be more favorable in patients with Beckwith-Wiedemann syndrome (BWS). In this case series, we review our experience with macroglossia associated with BWS, and we offer a new technique of central tongue reduction. Between 1993 and 2007, a retrospective chart review was conducted to include all patients with a diagnosis of BWS who have undergone stellate or double stellate tongue reduction at the Children's Hospital of Wisconsin. A total of 7 patients met all inclusion criteria. All patients had good tongue mobility at 1-year follow-up. One patient required speech therapy for persistent articulation errors postoperatively. A total of 2 patients required secondary procedures for recurrent macroglossia. There were no complaints of abnormal taste or sensation. The stellate and double stellate tongue reductions provide effective treatment in macroglossia associated with BWS.

REC-1 and HIM-5 distribute meiotic crossovers and function redundantly in meiotic double-strand break formation in Caenorhabditis elegans.

PubMed

Chung, George; Rose, Ann M; Petalcorin, Mark I R; Martin, Julie S; Kessler, Zebulin; Sanchez-Pulido, Luis; Ponting, Chris P; Yanowitz, Judith L; Boulton, Simon J

2015-09-15

The Caenorhabditis elegans gene rec-1 was the first genetic locus identified in metazoa to affect the distribution of meiotic crossovers along the chromosome. We report that rec-1 encodes a distant paralog of HIM-5, which was discovered by whole-genome sequencing and confirmed by multiple genome-edited alleles. REC-1 is phosphorylated by cyclin-dependent kinase (CDK) in vitro, and mutation of the CDK consensus sites in REC-1 compromises meiotic crossover distribution in vivo. Unexpectedly, rec-1; him-5 double mutants are synthetic-lethal due to a defect in meiotic double-strand break formation. Thus, we uncovered an unexpected robustness to meiotic DSB formation and crossover positioning that is executed by HIM-5 and REC-1 and regulated by phosphorylation. © 2015 Chung et al.; Published by Cold Spring Harbor Laboratory Press.

Multiporosity flow in fractured low-permeability rocks: Extension to shale hydrocarbon reservoirs

DOE PAGES

Kuhlman, Kristopher L.; Malama, Bwalya; Heath, Jason E.

2015-02-05

We presented a multiporosity extension of classical double and triple-porosity fractured rock flow models for slightly compressible fluids. The multiporosity model is an adaptation of the multirate solute transport model of Haggerty and Gorelick (1995) to viscous flow in fractured rock reservoirs. It is a generalization of both pseudo steady state and transient interporosity flow double-porosity models. The model includes a fracture continuum and an overlapping distribution of multiple rock matrix continua, whose fracture-matrix exchange coefficients are specified through a discrete probability mass function. Semianalytical cylindrically symmetric solutions to the multiporosity mathematical model are developed using the Laplace transform tomore » illustrate its behavior. Furthermore, the multiporosity model presented here is conceptually simple, yet flexible enough to simulate common conceptualizations of double and triple-porosity flow. This combination of generality and simplicity makes the multiporosity model a good choice for flow modelling in low-permeability fractured rocks.« less

Retinal optical coherence tomography image enhancement via shrinkage denoising using double-density dual-tree complex wavelet transform

PubMed Central

Mayer, Markus A.; Boretsky, Adam R.; van Kuijk, Frederik J.; Motamedi, Massoud

2012-01-01

Abstract. Image enhancement of retinal structures, in optical coherence tomography (OCT) scans through denoising, has the potential to aid in the diagnosis of several eye diseases. In this paper, a locally adaptive denoising algorithm using double-density dual-tree complex wavelet transform, a combination of the double-density wavelet transform and the dual-tree complex wavelet transform, is applied to reduce speckle noise in OCT images of the retina. The algorithm overcomes the limitations of commonly used multiple frame averaging technique, namely the limited number of frames that can be recorded due to eye movements, by providing a comparable image quality in significantly less acquisition time equal to an order of magnitude less time compared to the averaging method. In addition, improvements of image quality metrics and 5 dB increase in the signal-to-noise ratio are attained. PMID:23117804

Retinal optical coherence tomography image enhancement via shrinkage denoising using double-density dual-tree complex wavelet transform.

PubMed

Chitchian, Shahab; Mayer, Markus A; Boretsky, Adam R; van Kuijk, Frederik J; Motamedi, Massoud

2012-11-01

ABSTRACT. Image enhancement of retinal structures, in optical coherence tomography (OCT) scans through denoising, has the potential to aid in the diagnosis of several eye diseases. In this paper, a locally adaptive denoising algorithm using double-density dual-tree complex wavelet transform, a combination of the double-density wavelet transform and the dual-tree complex wavelet transform, is applied to reduce speckle noise in OCT images of the retina. The algorithm overcomes the limitations of commonly used multiple frame averaging technique, namely the limited number of frames that can be recorded due to eye movements, by providing a comparable image quality in significantly less acquisition time equal to an order of magnitude less time compared to the averaging method. In addition, improvements of image quality metrics and 5 dB increase in the signal-to-noise ratio are attained.

Channeling, channel density and mass recovery in aquifer transport, with application to the MADE experiment

NASA Astrophysics Data System (ADS)

Fiori, A.

2014-12-01

Channeling effects in heterogeneous formations are studied through a new quantity denoted as channel density a(x,t). Focusing on advection only, a(x,t) is defined as the relative number of streamtubes (or channels) containing solute between x and x + dx at a given time t, regardless of the mass that they carry. The channel density generally differs from the widely employed longitudinal mass distribution m(x,t), and their difference increases with time and the degree of heterogeneity. The difference between a and m reflects the nonuniformity of mass distribution relative to the plume geometry. In particular, the "fast" channels typically carry a larger fraction of mass than their share in their relative volume, which in turn can be rather small. Detecting such channels by a network of monitoring wells may be a challenging task, which might explain the poor solute recovery of some field experiments at increasing times. After application of the proposed concepts to the simple case of stratified formations, we model the channel density and mass distribution pertaining to the MADE experiment, which exhibited poor mass recovery at large times. The results presented in this study emphasize the possible channeling effects at MADE and the general difficulty in sampling the leading edge of the plume, which in turn may contain a significant fraction of the plume mass.

Understanding Mental Illness Stigma Toward Persons With Multiple Stigmatized Conditions: Implications of Intersectionality Theory.

PubMed

Oexle, Nathalie; Corrigan, Patrick W

2018-05-01

People with mental illness are often members of multiple stigmatized social groups. Therefore, experienced disadvantage might not be determined solely by mental illness stigma. Nevertheless, most available research does not consider the effects and implications of membership in multiple stigmatized social groups among people with mental illness. Reflecting on intersectionality theory, the authors discuss two intersectional effects determining disadvantage among people with mental illness who are members of multiple stigmatized social groups, namely double disadvantage and prominence. To be effective, interventions to reduce disadvantage experienced by people with mental illness need to be flexible and targeted rather than universal in order to address the implications of intersectionality. Whereas education-based approaches usually assume homogeneity and use universal strategies, contact-based interventions consider diversity among people with mental illness.

Tensile, Compression, Open-Hole Compression and Double Cantilever Beam Fracture Toughness Testing of Multiple NASA Langley Research Center Composite Materials

NASA Technical Reports Server (NTRS)

Adams, Donald F.

1999-01-01

The attached data summarizes the work performed by the Composite Materials Research Group at the University of Wyoming funded by the NASA LaRC Research Grant NAG-1-1294. The work consisted primarily of tension, compression, open-hole compression and double cantilever beam fracture toughness testing performed an a variety of NASA LaRC composite materials. Tests were performed at various environmental conditions and pre-conditioning requirements. The primary purpose of this work was to support the LaRC material development efforts. The data summaries are arranged in chronological order from oldest to newest.

Inductive Double-Contingency Analysis of UO2 Powder Bulk Blending Operations at a Commercial Fuel Plant (U)

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

Skiles, S. K.

1994-12-22

An inductive double-contingency analysis (DCA) method developed by the criticality safety function at the Savannah River Site, was applied in Criticality Safety Evaluations (CSEs) of five major plant process systems at the Westinghouse Electric Corporation`s Commercial Nuclear Fuel Manufacturing Plant in Columbia, South Carolina (WEC-Cola.). The method emphasizes a thorough evaluation of the controls intended to provide barriers against criticality for postulated initiating events, and has been demonstrated effective at identifying common mode failure potential and interdependence among multiple controls. A description of the method and an example of its application is provided.

Harmonic mode-locking using the double interval technique in quantum dot lasers.

PubMed

Li, Yan; Chiragh, Furqan L; Xin, Yong-Chun; Lin, Chang-Yi; Kim, Junghoon; Christodoulou, Christos G; Lester, Luke F

2010-07-05

Passive harmonic mode-locking in a quantum dot laser is realized using the double interval technique, which uses two separate absorbers to stimulate a specific higher-order repetition rate compared to the fundamental. Operating alone these absorbers would otherwise reinforce lower harmonic frequencies, but by operating together they produce the harmonic corresponding to their least common multiple. Mode-locking at a nominal 60 GHz repetition rate, which is the 10(th) harmonic of the fundamental frequency of the device, is achieved unambiguously despite the constraint of a uniformly-segmented, multi-section device layout. The diversity of repetition rates available with this method is also discussed.

Multiple forearm robotic elbow configuration

DOEpatents

Fisher, John J.

1990-01-01

A dual forearmed robotic elbow configuration comprises a main arm having a double elbow from which two coplanar forearms depend, two actuators carried in the double elbow for moving the forearms, and separate, independent end effectors, operated by a cable carried from the main arm through the elbow, is attached to the distal end of each forearm. Coiling the cables around the actuators prevents bending or kinking when the forearms are rotated 360 degrees. The end effectors can have similar or different capabilities. Actuator cannisters within the dual elbow are modular for rapid replacement or maintenance. Coarse and fine resolver transducers within the actuators provide accurate position referencing information.

Self-organized criticality in a cold plasma

NASA Astrophysics Data System (ADS)

Alex, Prince; Carreras, Benjamin Andres; Arumugam, Saravanan; Sinha, Suraj Kumar

2017-12-01

We present direct evidence for the existence of self-organized critical behavior in cold plasma. A multiple anodic double layer structure generated in a double discharge plasma setup shows critical behavior for the anode bias above a threshold value. Analysis of the floating potential fluctuations reveals the existence of long-range time correlations and power law behavior in the tail of the probability distribution function of the fluctuations. The measured Hurst exponent and the power law tail in the rank function are strong indication of the self-organized critical behavior of the system and hence provide a condition under which complexities arise in cold plasma.

Double-tailored nonimaging reflector optics for maximum-performance solar concentration.

PubMed

Goldstein, Alex; Gordon, Jeffrey M

2010-09-01

A nonimaging strategy that tailors two mirror contours for concentration near the étendue limit is explored, prompted by solar applications where a sizable gap between the optic and absorber is required. Subtle limitations of this simultaneous multiple surface method approach are derived, rooted in the manner in which phase space boundaries can be tailored according to the edge-ray principle. The fundamental categories of double-tailored reflective optics are identified, only a minority of which can pragmatically offer maximum concentration at high collection efficiency. Illustrative examples confirm that acceptance half-angles as large as 30 mrad can be realized at a flux concentration of approximately 1000.

[Subject and pain: introduction to a philosophy of medicine].

PubMed

Pérez Marc, Gonzalo

2010-10-01

Pain cannot be explained. It may only be understood from the most unpleasant of positions: suffering it. Thus, in the attempt to account for its multiple occurrences, meanings and mechanisms, developing a philosophy of pain appears to be essential. The approach to these issues by traditional occidental medicine has not considered the particular language in their background, which contains a double subjectivity: the subjectivity it represents itself, and that which frames the relationship between the agents where this language circulates. Articulating traditional scientific medicine with social, anthropological, and artistic disciplines would allow for a satisfactory response to this double subjectiveness, resulting in a deep change in current pain therapies.

Highway Accident Report: Multiple Vehicle Crossover Accident, Slinger, Wisconsin, February 12, 1997

DOT National Transportation Integrated Search

1998-07-24

About 5:52 a.m. on February 12, 1997, a doubles truck that was traveling northbound on U.S. Route 41 near Slinger, Wisconsin, lost control and crossed over the median into the southbound lanes. A flatbed truck traveling southbound on U.S. Route 41 co...

Using Functional Analysis Methodology to Evaluate Effects of an Atypical Antipsychotic on Severe Problem Behavior

ERIC Educational Resources Information Center

Danov, Stacy E.; Tervo, Raymond; Meyers, Stephanie; Symons, Frank J.

2012-01-01

The atypical antipsychotic medication aripiprazole was evaluated using a randomized AB multiple baseline, double-blind, placebo-controlled design for the treatment of severe problem behavior with 4 children with intellectual and developmental disabilities. Functional analysis (FA) was conducted concurrent with the medication evaluation to…

The Digital Sublime: Lessons from Kelli Connell's "Double Life"

ERIC Educational Resources Information Center

Huang, Yi-hui

2012-01-01

The digital sublime refers to digital-composite photography that presents "the existence of something unpresentable" and that renders a matchless look a sophisticated fabrication, a perfect and clean composition, a maximum color saturation, a multiple-point perspective, and stunning or newfangled content. Abandoning the traditional one-shot mode…

The "Double Bind" of Re-presentation in Qualitative Research Methods.

ERIC Educational Resources Information Center

Smithmier, Angela

A current movement in qualitative research is a preoccupation with representation of the "other" (Denzin and Lincoln 1994). Feminists, critical theorists and postmodernists have questioned the dominant, legitimized social order and remained sensitive to the multiple issues related to and emanating from power. This paper briefly reviews the…

Characterization of some useful traits in sweet sorghum for bioenergy production

USDA-ARS?s Scientific Manuscript database

Multiple yearly harvests can increase crop productivity but the crop may encounter different environmental challenges (such as early-spring cold or late-fall frost) depending on cultivation zones. Sweet sorghum as a feedstock may be planted early to get a double harvest or be rotated with sugarcane ...

Development of large volume double ring penning plasma discharge source for efficient light emissions

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

Prakash, Ram; Vyas, Gheesa Lal; Jain, Jalaj

In this paper, the development of large volume double ring Penning plasma discharge source for efficient light emissions is reported. The developed Penning discharge source consists of two cylindrical end cathodes of stainless steel having radius 6 cm and a gap 5.5 cm between them, which are fitted in the top and bottom flanges of the vacuum chamber. Two stainless steel anode rings with thickness 0.4 cm and inner diameters 6.45 cm having separation 2 cm are kept at the discharge centre. Neodymium (Nd{sub 2}Fe{sub 14}B) permanent magnets are physically inserted behind the cathodes for producing nearly uniform magnetic fieldmore » of {approx}0.1 T at the center. Experiments and simulations have been performed for single and double anode ring configurations using helium gas discharge, which infer that double ring configuration gives better light emissions in the large volume Penning plasma discharge arrangement. The optical emission spectroscopy measurements are used to complement the observations. The spectral line-ratio technique is utilized to determine the electron plasma density. The estimated electron plasma density in double ring plasma configuration is {approx}2 Multiplication-Sign 10{sup 11} cm{sup -3}, which is around one order of magnitude larger than that of single ring arrangement.« less

Deletions at short direct repeats and base substitutions are characteristic mutations for bleomycin-induced double- and single-strand breaks, respectively, in a human shuttle vector system

NASA Technical Reports Server (NTRS)

Dar, M. E.; Jorgensen, T. J.

1995-01-01

Using the radiomimetic drug, bleomycin, we have determined the mutagenic potential of DNA strand breaks in the shuttle vector pZ189 in human fibroblasts. The bleomycin treatment conditions used produce strand breaks with 3'-phosphoglycolate termini as > 95% of the detectable dose-dependent lesions. Breaks with this end group represent 50% of the strand break damage produced by ionizing radiation. We report that such strand breaks are mutagenic lesions. The type of mutation produced is largely determined by the type of strand break on the plasmid (i.e. single versus double). Mutagenesis studies with purified DNA forms showed that nicked plasmids (i.e. those containing single-strand breaks) predominantly produce base substitutions, the majority of which are multiples, which presumably originate from error-prone polymerase activity at strand break sites. In contrast, repair of linear plasmids (i.e. those containing double-strand breaks) mainly results in deletions at short direct repeat sequences, indicating the involvement of illegitimate recombination. The data characterize the nature of mutations produced by single- and double-strand breaks in human cells, and suggests that deletions at direct repeats may be a 'signature' mutation for the processing of DNA double-strand breaks.

Double heterozygotes among breast cancer patients analyzed for BRCA1, CHEK2, ATM, NBN/NBS1, and BLM germ-line mutations.

PubMed

Sokolenko, Anna P; Bogdanova, Natalia; Kluzniak, Wojciech; Preobrazhenskaya, Elena V; Kuligina, Ekatherina S; Iyevleva, Aglaya G; Aleksakhina, Svetlana N; Mitiushkina, Natalia V; Gorodnova, Tatiana V; Bessonov, Alexandr A; Togo, Alexandr V; Lubiński, Jan; Cybulski, Cezary; Jakubowska, Anna; Dörk, Thilo; Imyanitov, Evgeny N

2014-06-01

17 double heterozygous (DH) breast cancer (BC) patients were identified upon the analysis of 5,391 affected women for recurrent Slavic mutations in BRCA1, CHEK2, NBN/NBS1, ATM, and BLM genes. Double heterozygosity was found for BRCA1 and BLM (4 patients), BRCA1 and CHEK2 (4 patients), CHEK2 and NBS1 (3 patients), BRCA1 and ATM (2 patients), CHEK2 and BLM (2 patients), CHEK2 and ATM (1 patient), and NBS1 and BLM (1 patient). DH BC patients were on average not younger than single mutation carriers and did not have an excess of bilateral BC; an additional non-breast tumor was documented in two BRCA1/BLM DH patients (ovarian cancer and lymphoplasmacytic lymphoma). Loss-of-heterozygosity (LOH) analysis of involved genes was performed in 5 tumors, and revealed a single instance of somatic loss of the wild-type allele (LOH at CHEK2 locus in BRCA1/CHEK2 double heterozygote). Distribution of mutations in patients and controls favors the hypothesis on multiplicative interaction between at least some of the analyzed genes. Other studies on double heterozygosity for BC-predisposing germ-line mutations are reviewed.

Multiple Etalon Systems for the Advanced Technology Solar Telescope

NASA Technical Reports Server (NTRS)

Gary, G. Allen; Balasubramaniam, K. S.; Sigwarth, Michael; Six, N. Frank (Technical Monitor)

2002-01-01

Multiple etalons systems are discussed that meet the 4-meter NSO/Advance Technology Solar Telescope (http://www.nso.edu/ATST/index.html) instrument and science requirements for a narrow bandpass imaging system. A multiple etalon system can provide an imaging interferometer working in four distinct modes: as a spectro-polarimeter, a filter-vector magnetograph, and a wide-band and broad-band high-resolution imager. Specific dual and triple etalon configurations will be described that provides spectrographic passband of 2.0-3.5nm and reduces parasitic light levels to 1/10000 as required by precise polarization measurement, e.g., Zeeman measurements of magnetic sensitive lines. A TESOS-like triple etalon system provides for spectral purity of 100 thousandths. The triple designs have the advantage of reducing the finesse requirement on each etalon, allowing much more stable blocking filters, and can have very high spectral purity. A dual-etalon double-pass Cavallini-like configuration can provide a competing configuration. This design can provide high contrast with only a double etalon. The selection of the final focal plan instrument will depend on a trade-off of the ideal instrument versus reality, the number of etalons, the aperture of etalons, the number of blocking filters the electronic control system and computer interfaces, the temperature control and controllers for the etalons and the electronics. The use of existing experience should provide significant cost savings. The heritage of use of etalons and multiple etalon systems in solar physics come from a number of observatories, which includes MSFC Solar Observatory (NASA), Sac Peak Observatory (NSO), and Kiepenheuer Institute for Solar Physics (Germany), Mees Solar Observatory (University of Hawaii), and Arcetri Astrophysical Observatory (Italy). The design of the ATST multiple etalon system will reply on the existing experience from these observatories.

Dietary Leucine - An Environmental Modifier of Insulin Resistance Acting on Multiple Levels of Metabolism

PubMed Central

Macotela, Yazmin; Emanuelli, Brice; Bång, Anneli M.; Espinoza, Daniel O.; Boucher, Jeremie; Beebe, Kirk; Gall, Walter; Kahn, C. Ronald

2011-01-01

Environmental factors, such as the macronutrient composition of the diet, can have a profound impact on risk of diabetes and metabolic syndrome. In the present study we demonstrate how a single, simple dietary factor—leucine—can modify insulin resistance by acting on multiple tissues and at multiple levels of metabolism. Mice were placed on a normal or high fat diet (HFD). Dietary leucine was doubled by addition to the drinking water. mRNA, protein and complete metabolomic profiles were assessed in the major insulin sensitive tissues and serum, and correlated with changes in glucose homeostasis and insulin signaling. After 8 weeks on HFD, mice developed obesity, fatty liver, inflammatory changes in adipose tissue and insulin resistance at the level of IRS-1 phosphorylation, as well as alterations in metabolomic profile of amino acid metabolites, TCA cycle intermediates, glucose and cholesterol metabolites, and fatty acids in liver, muscle, fat and serum. Doubling dietary leucine reversed many of the metabolite abnormalities and caused a marked improvement in glucose tolerance and insulin signaling without altering food intake or weight gain. Increased dietary leucine was also associated with a decrease in hepatic steatosis and a decrease in inflammation in adipose tissue. These changes occurred despite an increase in insulin-stimulated phosphorylation of p70S6 kinase indicating enhanced activation of mTOR, a phenomenon normally associated with insulin resistance. These data indicate that modest changes in a single environmental/nutrient factor can modify multiple metabolic and signaling pathways and modify HFD induced metabolic syndrome by acting at a systemic level on multiple tissues. These data also suggest that increasing dietary leucine may provide an adjunct in the management of obesity-related insulin resistance. PMID:21731668

Combined unilateral blockade of cholinergic, peptidergic, and serotonergic receptors in the ventral respiratory column does not affect breathing in awake or sleeping goats

PubMed Central

Muere, Clarissa; Neumueller, Suzanne; Olesiak, Samantha; Miller, Justin; Langer, Thomas; Hodges, Matthew R.; Pan, Lawrence

2015-01-01

Previous work in intact awake and sleeping goats has found that unilateral blockade of excitatory inputs in the ventral respiratory column (VRC) elicits changes in the concentrations of multiple neurochemicals, including serotonin (5-HT), substance P, glycine, and GABA, while increasing or having no effect on breathing. These findings are consistent with the concept of interdependence between neuromodulators, whereby attenuation of one modulator elicits compensatory changes in other modulators to maintain breathing. Because there is a large degree of redundancy and multiplicity of excitatory inputs to the VRC, we herein tested the hypothesis that combined unilateral blockade of muscarinic acetylcholine (mACh), neurokinin-1 (NK1, the receptor for substance P), and 5-HT2A receptors would elicit changes in multiple neurochemicals, but would not change breathing. We unilaterally reverse-dialyzed a cocktail of antagonists targeting these receptors into the VRC of intact adult goats. Breathing was continuously monitored while effluent fluid from dialysis was collected for quantification of neurochemicals. We found that neither double blockade of mACh and NK1 receptors, nor triple blockade of mACh, NK1, and 5-HT2A receptors significantly affected breathing (P ≥ 0.05) in goats that were awake or in non-rapid eye movement (NREM) sleep. However, both double and triple blockade increased the effluent concentration of substance P (P < 0.001) and decreased GABA concentrations. These findings support our hypothesis and, together with past data, suggest that both in wakefulness and NREM sleep, multiple neuromodulator systems collaborate to stabilize breathing when a deficit in one or multiple excitatory neuromodulators exists. PMID:26023224

A highly tunable system for the simultaneous expression of multiple enzymes in Saccharomyces cerevisiae.

PubMed

Ito, Yoichiro; Yamanishi, Mamoru; Ikeuchi, Akinori; Matsuyama, Takashi

2015-01-16

Control of the expression levels of multiple enzymes in transgenic yeasts is essential for the effective production of complex molecules through fermentation. Here, we propose a tunable strategy for the control of expression levels based on the design of terminator regions and other gene-expression control elements in Saccharomyces cerevisiae. Our genome-integrated system, which is capable of producing high expression levels over a wide dynamic range, will broadly enable metabolic engineering and synthetic biology. We demonstrated that the activities of multiple cellulases and the production of ethanol were doubled in a transgenic yeast constructed with our system compared with those achieved with a standard expression system.

Formation of multiple focal spots using a high NA lens with a complex spiral phase mask

NASA Astrophysics Data System (ADS)

Lalithambigai, K.; Anbarasan, P. M.; Rajesh, K. B.

2014-07-01

The formation of a transversally polarized beam by transmitting a tightly focused double-ring-shaped azimuthally polarized beam through a complex spiral phase mask and high numerical aperture lens is presented based on vector diffraction theory. The generation of transversally polarized focal spot segment splitting and multiple focal spots is illustrated numerically. Moreover, we found that a properly designed complex spiral phase mask can move the focal spots along the optical axis in the z direction. Therefore, one can achieve a focal segment of two, three or multiple completely transversely polarized focal spots, which finds applications in optical trapping and in material processing technologies.

Metal-Free Multiple Carbon-Carbon and Carbon-Hydrogen Bond Activations via Charge-Switching Mechanism in Unstrained Diindolylmethanes.

PubMed

Challa, Chandrasekhar; Varughese, Sunil; Suresh, Cherumuttathu H; Lankalapalli, Ravi S

2017-08-18

A transformation of the unstrained phenol substituted 3,3'-diindolylmethanes (DIPMs) to 2,3'-diindolylketones (DIKs) by double C-C single bond cleavage with associated rearrangements, triggered by phenyliodine(III) diacetate (PIDA), is reported. Density functional theory studies reveal a mechanism involving multiple "charge-switching" steps by synergistic involvement of the two indole units with overall low activation energy. The indole 'charge-switching' mechanism in DIPMs was further extended toward synthesis of a natural product motif cyclohepta[b]indole from biaryl appended DIBM.

Highly efficient organic light-emitting diodes with a quantum dot interfacial layer.

PubMed

Ryu, Seung Yoon; Hwang, Byoung Har; Park, Ki Wan; Hwang, Hyeon Seok; Sung, Jin Woo; Baik, Hong Koo; Lee, Chang Ho; Song, Seung Yong; Lee, Jun Yeob

2009-02-11

Advanced organic light-emitting diodes (OLEDs), based on a multiple structure, were achieved in combination with a quantum dot (QD) interfacial layer. The authors used core/shell CdSe/ZnS QDs passivated with trioctylphosphine oxide (TOPO) and TOPO-free QDs as interlayers. Multiple-structure OLEDs (MOLEDs) with TOPO-free QDs showed higher device efficiency because of a well-defined interfacial monolayer formation. Additionally, the three-unit MOLED showed high performance for device efficiency with double-structured QD interfacial layers due to the enhanced charge balance and recombination probability.

An improved multiple linear regression and data analysis computer program package

NASA Technical Reports Server (NTRS)

Sidik, S. M.

1972-01-01

NEWRAP, an improved version of a previous multiple linear regression program called RAPIER, CREDUC, and CRSPLT, allows for a complete regression analysis including cross plots of the independent and dependent variables, correlation coefficients, regression coefficients, analysis of variance tables, t-statistics and their probability levels, rejection of independent variables, plots of residuals against the independent and dependent variables, and a canonical reduction of quadratic response functions useful in optimum seeking experimentation. A major improvement over RAPIER is that all regression calculations are done in double precision arithmetic.

Single and double acquisition strategies for compensation of artifacts from eddy current and transient oscillation in balanced steady-state free precession.

PubMed

Lee, Hyun-Soo; Choi, Seung Hong; Park, Sung-Hong

2017-07-01

To develop single and double acquisition methods to compensate for artifacts from eddy currents and transient oscillations in balanced steady-state free precession (bSSFP) with centric phase-encoding (PE) order for magnetization-prepared bSSFP imaging. A single and four different double acquisition methods were developed and evaluated with Bloch equation simulations, phantom/in vivo experiments, and quantitative analyses. For the single acquisition method, multiple PE groups, each of which was composed of N linearly changing PE lines, were ordered in a pseudocentric manner for optimal contrast and minimal signal fluctuations. Double acquisition methods used complex averaging of two images that had opposite artifact patterns from different acquisition orders or from different numbers of dummy scans. Simulation results showed high sensitivity of eddy-current and transient-oscillation artifacts to off-resonance frequency and PE schemes. The artifacts were reduced with the PE-grouping with N values from 3 to 8, similar to or better than the conventional pairing scheme of N = 2. The proposed double acquisition methods removed the remaining artifacts significantly. The proposed methods conserved detailed structures in magnetization transfer imaging well, compared with the conventional methods. The proposed single and double acquisition methods can be useful for artifact-free magnetization-prepared bSSFP imaging with desired contrast and minimized dummy scans. Magn Reson Med 78:254-263, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

Longitudinal studies of Aedes aegypti (Diptera: Culicidae) in Thailand and Puerto Rico: blood feeding frequency.

PubMed

Scott, T W; Amerasinghe, P H; Morrison, A C; Lorenz, L H; Clark, G G; Strickman, D; Kittayapong, P; Edman, J D

2000-01-01

We used a histologic technique to study multiple blood feeding in a single gonotrophic cycle by engorged Aedes aegypti (L.) that were collected weekly for 2 yr from houses in a rural village in Thailand (n = 1,891) and a residential section of San Juan, Puerto Rico (n = 1,675). Overall, mosquitoes from Thailand contained significantly more multiple meals (n = 1,300, 42% double meals, 5% triple meals) than mosquitoes collected in Puerto Rico (n = 1,156, 32% double meals, 2% triple meals). The portion of specimens for which frequency of feeding could not be determined was 31% at both sites. We estimated that on average Ae. aegypti take 0.76 and 0.63 human blood meals per day in Thailand and Puerto Rico, respectively. However, frequency of multiple feeding varied among houses and, in Puerto Rico, the neighborhoods from which mosquitoes were collected. In Thailand 65% of the mosquitoes fed twice on the same day, whereas in Puerto Rico 57% took multiple meals separated by > or = 1 d. At both sites, the majority of engorged specimens were collected inside houses (Thailand 86%, Puerto Rico 95%). The number of blood meals detected was independent of where mosquitoes were collected (inside versus outside of the house) at both sites and the time of day collections were made in Puerto Rico. Feeding rates were slightly higher for mosquitoes collected in the afternoon in Thailand. Temperatures were significantly higher and mosquitoes significantly smaller in Thailand than in Puerto Rico. At both sites female size was negatively associated with temperature. Rates of multiple feeding were associated positively with temperature and negatively with mosquito size in Thailand, but not in Puerto Rico. Multiple feeding during a single gonotrophic cycle is a regular part of Ae. aegypti biology, can vary geographically and under different climate conditions, and may be associated with variation in patterns of dengue virus transmission.

A Candidate Gene Analysis of Methylphenidate Response in Attention-Deficit/Hyperactivity Disorder

ERIC Educational Resources Information Center

McGough, James J.; McCracken, James T.; Loo, Sandra K.; Manganiello, Marc; Leung, Michael C.; Tietjens, Jeremy R.; Trinh, Thao; Baweja, Shilpa; Suddath, Robert; Smalley, Susan L.; Hellemann, Gerhard; Sugar, Catherine A.

2009-01-01

Objective: This study examines the potential role of candidate genes in moderating treatment effects of methylphenidate (MPH) in attention-deficit/hyperactivity disorder (ADHD). Method: Eighty-two subjects with ADHD aged 6 to 17 years participated in a prospective, double-blind, placebo-controlled, multiple-dose, crossover titration trial of…

Discrimination in the Lives of Older Black Women.

ERIC Educational Resources Information Center

Lykes, M. Brinton

Black women have been described as being in "double jeopardy" due to the combined effects of racism and sexism. To explore the multiple effects of institutional discrimination and prejudice based on race and/or sex, the experiences of 52 highly successful older black women were examined, using tapes from the Black Women Oral History…

Teaching Mathematics by Comparison: Analog Visibility as a Double-Edged Sword

ERIC Educational Resources Information Center

Begolli, Kreshnik Nasi; Richland, Lindsey Engle

2016-01-01

Comparing multiple solutions to a single problem is an important mode for developing flexible mathematical thinking, yet instructionally leading this activity is challenging (Stein, Engle, Smith, & Hughes, 2008). We test 1 decision teachers must make after having students solve a problem: whether to only verbally discuss students' solutions or…

A DNA Melting Exercise for a Large Laboratory Class

ERIC Educational Resources Information Center

Levine, Lauren A.; Junker, Matthew; Stark, Myranda; Greenleaf, Dustin

2015-01-01

A simple and economical experimental setup is described that enables multiple individuals or groups within a laboratory class to measure the thermal melting of double stranded DNA simultaneously. The setup utilizes a basic spectrophotometer capable of measuring absorbance at 260 nm, UV plastic cuvettes, and a stirring hot plate. Students measure…

Using Poetic Documents: An Exploration of Poststructuralist Ideas and Poetic Practices in Narrative Therapy

ERIC Educational Resources Information Center

Speedy, Jane

2005-01-01

This paper explores the use of poetic documents in narrative therapy practice. It considers the ways in which feminist and poststructuralist ideas inform these practices and speculates about the extent to which a "poetic-mindedness" might sustain the practice of double- (or multiple-) listening. The author illustrates these explorations…

How do stars form

NASA Astrophysics Data System (ADS)

Tscharnuter, W. M.

1980-02-01

Modes and model concept of star formation are reviewed, beginning with the theory of Kant (1755), via Newton's exact mathematical formulation of the laws of motion, his recognition of the universal validity of general gravitation, to modern concepts and hypotheses. Axisymmetric and spherically symmetric collapse models are discussed, and the origin of double and multiple star systems is examined.

Prototype solar heated hot water systems and double-walled heat exchangers: A collection of quarterly reports

NASA Technical Reports Server (NTRS)

1978-01-01

The plan schedule and status of multiple objectives to be achieved in the development, manufacture, installation, and maintenance of two solar heated hot water prototype systems and two heat exchangers are reported. A computer program developed to resolve problems and evaluate system performance is described.

Influence of multiple blood meals on gonotrophic dissociation and fecundity in Aedes albopictus

USDA-ARS?s Scientific Manuscript database

Female Aedes albopictus blood fed on guinea pig and human hosts produced significantly (P < 0.05) higher number of eggs (80 and 82/female, respectively) than females fed on chicken (67 eggs/female). Fecundity in mosquitoes that took a double blood meal (chicken and guinea pig), a triple blood meal ...

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

Creutz, Michael

Using the Sigma model to explore the lowest order pseudo-scalar spectrum with SU(3) breaking, this talk considers an additional exact "taste" symmetry to mimic species doubling. Rooting replicas of a valid approach such as Wilson fermions reproduces the desired physical spectrum. In contrast, extra symmetries of the rooted staggered approach leave spurious states and a flavor dependent taste multiplicity.

Monte Carlo approach in assessing damage in higher order structures of DNA

NASA Technical Reports Server (NTRS)

Chatterjee, A.; Schmidt, J. B.; Holley, W. R.

1994-01-01

We have developed a computer monitor of nuclear DNA in the form of chromatin fibre. The fibres are modeled as a ideal solenoid consisting of twenty helical turns with six nucleosomes per turn. The chromatin model, in combination with are Monte Carlo theory of radiation damage induces by charged particles, based on general features of tack structure and stopping power theory, has been used to evaluate the influence of DNA structure on initial damage. An interesting has emerged from our calculations. Our calculated results predict the existence of strong spatial correlations in damage sites associated with the symmetries in the solenoidal model. We have calculated spectra of short fragments of double stranded DNA produced by multiple double strand breaks induced by both high and low LET radiation. The spectra exhibit peaks at multiples of approximately 85 base pairs (the nucleosome periodicity), and approximately 1000 base pairs (solenoid periodicity). Preliminary experiments to investigate the fragment distributions from irradiated DNA, made by B. Rydberg at Lawrence Berkeley Laboratory, confirm the existence of short DNA fragments and are in substantial agreement with the predictions of our theory.

Strain and deformations engineered germanene bilayer double gate-field effect transistor by first principles

NASA Astrophysics Data System (ADS)

Meher Abhinav, E.; Chandrasekaran, Gopalakrishnan; Kasmir Raja, S. V.

2017-10-01

Germanene, silicene, stanene, phosphorene and graphene are some of single atomic materials with novel properties. In this paper, we explored bilayer germanene-based Double Gate-Field Effect Transistor (DG-FET) with various strains and deformations using Density Functional Theory (DFT) and Green's approach by first-principle calculations. The DG-FET of 1.6 nm width, 6 nm channel length (Lch) and HfO2 as gate dielectric has been modeled. For intrinsic deformation of germanene bilayer, we have enforced minute mechanical deformation of wrap and twist (5°) and ripple (0.5 Å) on germanene bilayer channel material. By using NEGF formalism, I-V Characteristics of various strains and deformation tailored DG-FET was calculated. Our results show that rough edge and single vacancy (5-9) in bilayer germanene diminishes the current around 47% and 58% respectively as compared with pristine bilayer germanene. In case of strain tailored bilayer DG-FET, multiple NDR regions were observed which can be utilized in building stable multiple logic states in digital circuits and high frequency oscillators using negative resistive techniques.

Ordered three- and five-ply nanocomposites from ABC block terpolymer microphase separation with niobia and aluminosilicate sols

PubMed Central

Stefik, Morgan; Mahajan, Surbhi; Sai, Hiroaki; Epps, Thomas H.; Bates, Frank S.; Gruner, Sol M; DiSalvo, Francis J.; Wiesner, Ulrich

2009-01-01

We report the first use of a non-frustrated block terpolymer for the synthesis of highly ordered oxide nanocomposites containing multiple plies. The morphological behavior of 15 ISO-oxide nanocomposites was investigated spanning a large range of compositions along the ƒI=ƒS isopleth using aluminosilicate and niobia sols. Morphologies were determined by TEM and SAXS measurements. Four morphologies were identified, including core-shell hexagonal, core-shell double gyroid, three-domain lamellae, and core-shell inverse-hexagonal, in order of increasing O+oxide vol fraction. All of the resulting nanocomposites had three- or five-ply morphologies containing domains that were continuous in one, two, or three dimensions. The five-ply core-shell double gyroid phase was only found to be stable when the O+oxide domain was a minority. Removal of the polymer enabled simple and direct synthesis of mesoporous oxide materials while retaining the ordered network structure. We believe that advances in the synthesis of multi-ply nanocomposites will lead to advanced materials and devices containing multiple plies of functional materials. PMID:20209023

Ordered three- and five-ply nanocomposites from ABC block terpolymer microphase separation with niobia and aluminosilicate sols.

PubMed

Stefik, Morgan; Mahajan, Surbhi; Sai, Hiroaki; Epps, Thomas H; Bates, Frank S; Gruner, Sol M; Disalvo, Francis J; Wiesner, Ulrich

2009-11-24

We report the first use of a non-frustrated block terpolymer for the synthesis of highly ordered oxide nanocomposites containing multiple plies. The morphological behavior of 15 ISO-oxide nanocomposites was investigated spanning a large range of compositions along the ƒ(I)=ƒ(S) isopleth using aluminosilicate and niobia sols. Morphologies were determined by TEM and SAXS measurements. Four morphologies were identified, including core-shell hexagonal, core-shell double gyroid, three-domain lamellae, and core-shell inverse-hexagonal, in order of increasing O+oxide vol fraction. All of the resulting nanocomposites had three- or five-ply morphologies containing domains that were continuous in one, two, or three dimensions. The five-ply core-shell double gyroid phase was only found to be stable when the O+oxide domain was a minority. Removal of the polymer enabled simple and direct synthesis of mesoporous oxide materials while retaining the ordered network structure. We believe that advances in the synthesis of multi-ply nanocomposites will lead to advanced materials and devices containing multiple plies of functional materials.

Wave interactions with multiple semi-immersed Jarlan-type perforated breakwaters

NASA Astrophysics Data System (ADS)

Elbisy, Moussa S.

2017-06-01

This study examines wave interactions with multiple semi-immersed Jarlan-type perforated breakwaters. A numerical model based on linear wave theory and an eigenfunction expansion method has been developed to study the hydrodynamic characteristics of breakwaters. The numerical results show a good agreement with previous analytical results and experimental data for limiting cases of double partially immersed impermeable walls and double and triple Jarlan-type breakwaters. The wave transmission coefficient C T; reflection coefficient C R, and energy dissipation coefficient C E coefficients and the horizontal wave force exerted on the front and rear walls are examined. The results show that C R reaches the maximum value when B/L = 0.46 n while it is smallest when B/L=0.46 n+0.24 ( n=0, 1, 2,...). An economical triple semi-immersed Jarlan-type perforated breakwater can be designed with B/L = 0.25 and C R and C T ranging from 0.25 to 0.32 by choosing a relative draft d/h of 0.35 and a permeability parameter of the perforated front walls being 0.5 for an incident wave number kh nearly equal to 2.0. The triple semi-immersed Jarlan-type perforated breakwaters with significantly reduced C R, will enhance the structure's wave absorption ability, and lead to smaller wave forces compared with the double one. The proposed model may be used to predict the response of a structure in the preliminary design stage for practical engineering.

Double-strand break repair-adox: Restoration of suppressed double-strand break repair during mitosis induces genomic instability.

PubMed

Terasawa, Masahiro; Shinohara, Akira; Shinohara, Miki

2014-12-01

Double-strand breaks (DSBs) are one of the severest types of DNA damage. Unrepaired DSBs easily induce cell death and chromosome aberrations. To maintain genomic stability, cells have checkpoint and DSB repair systems to respond to DNA damage throughout most of the cell cycle. The failure of this process often results in apoptosis or genomic instability, such as aneuploidy, deletion, or translocation. Therefore, DSB repair is essential for maintenance of genomic stability. During mitosis, however, cells seem to suppress the DNA damage response and proceed to the next G1 phase, even if there are unrepaired DSBs. The biological significance of this suppression is not known. In this review, we summarize recent studies of mitotic DSB repair and discuss the mechanisms of suppression of DSB repair during mitosis. DSB repair, which maintains genomic integrity in other phases of the cell cycle, is rather toxic to cells during mitosis, often resulting in chromosome missegregation and aberration. Cells have multiple safeguards to prevent genomic instability during mitosis: inhibition of 53BP1 or BRCA1 localization to DSB sites, which is important to promote non-homologous end joining or homologous recombination, respectively, and also modulation of the non-homologous end joining core complex to inhibit DSB repair. We discuss how DSBs during mitosis are toxic and the multiple safeguard systems that suppress genomic instability. © 2014 The Authors. Cancer Science published by Wiley Publishing Asia Pty Ltd on behalf of Japanese Cancer Association.

Interferential and horizontal therapies in chronic low back pain due to multiple vertebral fractures: a randomized, double blind, clinical study.

PubMed

Zambito, A; Bianchini, D; Gatti, D; Rossini, M; Adami, S; Viapiana, O

2007-11-01

Chronic low back pain due to multiple vertebral fractures is of difficult management. Electrical nerve stimulation is frequently used, but its efficacy has never been properly evaluated. In a randomized placebo-controlled clinical trial, we have shown that both interferential currents and horizontal therapy are more effective than placebo for functional. Multiple vertebral fractures almost invariably ensue in chronic low back pain that remains of difficult management. Electrical nerve stimulation is frequently used but its efficacy has never been properly evaluated. One hundred and fifteen women with chronic back pain due to previous multiple vertebral osteoporotic fractures (CBPMF) were randomly assigned to either interferential currents (IFT), horizontal therapy (HT) or sham HT administered for 30 minutes daily for 5 days per week for two weeks together with a standard exercise program. Efficacy assessment was obtained at baseline and at week 2, 6 and 14 and included a functional questionnaire (Backill), the standard visual analog scale (VAS) and the mean analgesic consumption. At week 2 a significant and similar improvement in both the VAS and Backill score was observed in the three groups. The two scores continued to improve in the two active groups with changes significantly (p < 0.001) greater than those observed in control patients at week 6 and 14. The use of analgesic medications improved only in the HT group. This randomized double-blind controlled study provides the first evidence that IFT and HT therapy are significantly effective in alleviating both pain and disability in patients with CBPMF.

Fresh Fuel Measurements With the Differential Die-Away Self-Interrogation Instrument

NASA Astrophysics Data System (ADS)

Trahan, Alexis C.; Belian, Anthony P.; Swinhoe, Martyn T.; Menlove, Howard O.; Flaska, Marek; Pozzi, Sara A.

2017-07-01

The purpose of the Next Generation Safeguards Initiative (NGSI)-Spent Fuel (SF) Project is to strengthen the technical toolkit of safeguards inspectors and/or other interested parties. The NGSI-SF team is working to achieve the following technical goals more easily and efficiently than in the past using nondestructive assay measurements of spent fuel assemblies: 1) verify the initial enrichment, burnup, and cooling time of facility declaration; 2) detect the diversion or replacement of pins; 3) estimate the plutonium mass; 4) estimate decay heat; and 5) determine the reactivity of spent fuel assemblies. The differential die-away self-interrogation (DDSI) instrument is one instrument that was assessed for years regarding its feasibility for robust, timely verification of spent fuel assemblies. The instrument was recently built and was tested using fresh fuel assemblies in a variety of configurations, including varying enrichment, neutron absorber content, and symmetry. The early die-away method, a multiplication determination method developed in simulation space, was successfully tested on the fresh fuel assembly data and determined multiplication with a root-mean-square (RMS) error of 2.9%. The experimental results were compared with MCNP simulations of the instrument as well. Low multiplication assemblies had agreement with an average RMS error of 0.2% in the singles count rate (i.e., total neutrons detected per second) and 3.4% in the doubles count rates (i.e., neutrons detected in coincidence per second). High-multiplication assemblies had agreement with an average RMS error of 4.1% in the singles and 13.3% in the doubles count rates.

Comparison of Two Types of Double-J Ureteral Stents that Differ in Diameter and the Existence of Multiple Side Holes along the Straight Portion in Malignant Ureteral Strictures.

PubMed

Song, Myung Gyu; Seo, Tae-Seok; Lee, Chang Hee; Kim, Kyeong Ah; Kim, Jun Suk; Oh, Sang Cheul; Lee, Jae-Kwan

2015-06-01

This study was decided to evaluate the impact of diameter and the existences of multiple side holes along the straight portion of double-J ureteral stents (DJUS) on early dysfunction of stents placed for malignant ureteral strictures. Between April 2007 and December 2011, 141 DJUSs were placed via a percutaneous nephrostomy (PCN) tract in 110 consecutive patients with malignant ureteral strictures. 7F DJUSs with multiple side holes in the straight portion were placed in 58 ureters of 43 patients (Group 1). 8F DJUSs with three side holes in the proximal 2-cm of the straight portion were placed in 83 ureters of 67 patients (Group 2). The incidence of early DJUS dysfunction was compared between the two groups, and nephrostographic findings were evaluated in the cases of early dysfunction. Early dysfunction of the DJUS was noted in 14 of 58 patients (24.1 %) in Group 1, which was significantly higher (p = 0.001) than in Group 2 in which only 1 of 83 patients (1.2 %) had early dysfunction of the DJUS. Nephrostographic findings of early dysfunction included dilatation of the pelvicalyceal system, filling defects in the ureteral stent, and no passage of contrast media into the urinary bladder. In malignant ureteral strictures, multiple side holes in the straight portion of the 7-F DJUS seem to cause early dysfunction. The 8F DJUSs with three side holes in the proximal 2-cm of the straight portion may be superior at preventing early dysfunction.

Fresh Fuel Measurements With the Differential Die-Away Self-Interrogation Instrument

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

Trahan, Alexis C.; Belian, Anthony P.; Swinhoe, Martyn T.

The purpose of the Next Generation Safeguards Initiative (NGSI)-Spent Fuel (SF) Project is to strengthen the technical toolkit of safeguards inspectors and/or other interested parties. Thus the NGSI-SF team is working to achieve the following technical goals more easily and efficiently than in the past using nondestructive assay measurements of spent fuel assemblies: 1) verify the initial enrichment, burnup, and cooling time of facility declaration; 2) detect the diversion or replacement of pins; 3) estimate the plutonium mass; 4) estimate decay heat; and 5) determine the reactivity of spent fuel assemblies. The differential die-away self-interrogation (DDSI) instrument is one instrumentmore » that was assessed for years regarding its feasibility for robust, timely verification of spent fuel assemblies. The instrument was recently built and was tested using fresh fuel assemblies in a variety of configurations, including varying enrichment, neutron absorber content, and symmetry. The early die-away method, a multiplication determination method developed in simulation space, was successfully tested on the fresh fuel assembly data and determined multiplication with a root-mean-square (RMS) error of 2.9%. The experimental results were compared with MCNP simulations of the instrument as well. Low multiplication assemblies had agreement with an average RMS error of 0.2% in the singles count rate (i.e., total neutrons detected per second) and 3.4% in the doubles count rates (i.e., neutrons detected in coincidence per second). High-multiplication assemblies had agreement with an average RMS error of 4.1% in the singles and 13.3% in the doubles count rates.« less

Subclinical visual involvement in multiple sclerosis: a study by MRI, VEPs, frequency-doubling perimetry, standard perimetry, and contrast sensitivity.

PubMed

Sisto, Dario; Trojano, Maria; Vetrugno, Michele; Trabucco, Tiziana; Iliceto, Giovanni; Sborgia, Carlo

2005-04-01

To evaluate the effectiveness of visual evoked potentials (VEPs), frequency-doubling perimetry (FDP), standard achromatic perimetry (SAP), contrast sensitivity (CS) test, and magnetic resonance imaging (MRI), isolated or in combination, in detecting subclinical impairment of visual function in multiple sclerosis (MS). Twenty-two eyes of 11 patients affected by clinically definite MS, without a history of optic neuritis and asymptomatic for visual disturbances, underwent full ophthalmic examination and, in addition, VEPs, FDP, SAP, CS, and MRI. Abnormal results were taken to be as follows: for VEPs, a P100 latency >115 ms; for FDP, abnormal mean deviation (MD) or pattern SD (PSD); for SAP, abnormal MD or PSD; for CS, abnormal CS at one spatial frequency, at least; and for MRI, evidence of at least one demyelinating plaque along the visual pathway. VEPs showed abnormal results in 12 eyes (54.4%), FDP in 11 (50%), SAP in 14 (63.6%), CS in 17 (77.1%), and MRI in 16 (72.7%). In only two (9.1%) eyes of the same patient was no abnormality found. No single test detected all the abnormal eyes. Four (18.2%) eyes had pure optic nerve involvement and the remaining 16 (72.7%) had both pre- and postchiasmal involvement. In patients affected by clinically definite MS without history of optic neuritis and no visual symptoms, there is a large prevalence of visual pathway involvement that can be diagnosed only by performing multiple tests. The comparison of the tests is also useful to detect the presence of multiple lesions in the same patient.

Fresh Fuel Measurements With the Differential Die-Away Self-Interrogation Instrument

DOE PAGES

Trahan, Alexis C.; Belian, Anthony P.; Swinhoe, Martyn T.; ...

2017-01-05

The purpose of the Next Generation Safeguards Initiative (NGSI)-Spent Fuel (SF) Project is to strengthen the technical toolkit of safeguards inspectors and/or other interested parties. Thus the NGSI-SF team is working to achieve the following technical goals more easily and efficiently than in the past using nondestructive assay measurements of spent fuel assemblies: 1) verify the initial enrichment, burnup, and cooling time of facility declaration; 2) detect the diversion or replacement of pins; 3) estimate the plutonium mass; 4) estimate decay heat; and 5) determine the reactivity of spent fuel assemblies. The differential die-away self-interrogation (DDSI) instrument is one instrumentmore » that was assessed for years regarding its feasibility for robust, timely verification of spent fuel assemblies. The instrument was recently built and was tested using fresh fuel assemblies in a variety of configurations, including varying enrichment, neutron absorber content, and symmetry. The early die-away method, a multiplication determination method developed in simulation space, was successfully tested on the fresh fuel assembly data and determined multiplication with a root-mean-square (RMS) error of 2.9%. The experimental results were compared with MCNP simulations of the instrument as well. Low multiplication assemblies had agreement with an average RMS error of 0.2% in the singles count rate (i.e., total neutrons detected per second) and 3.4% in the doubles count rates (i.e., neutrons detected in coincidence per second). High-multiplication assemblies had agreement with an average RMS error of 4.1% in the singles and 13.3% in the doubles count rates.« less

Mechanical characteristics and comparisons of cerclage wires: introduction of the double-wrap and loop/twist tying methods.

PubMed

Roe, S C

1997-01-01

Evaluate the mechanical properties of twist, loop, double loop, double-wrap and loop/twist cerclage. The initial tension generated by 18 cerclage of each type was determined using a materials testing machine after tying around a testing jig. Six wires from each type were distracted and the initial stiffness and yield load were determined. Yield behavior was further investigated in six wires of each type by determining the load required to reduce cerclage tension below 30 Newton (N) following and incremental (50 N) stepwise load and unload regimen. The amount of collapse of the simulated bone fragments that resulted in the reduction of initial tension to 30 N was measured for the final six wires of each group. Data were analyzed by analysis of variance and a multiple comparison test. Twist type cerclage generated less tension than loop-type cerclage. The yield load of these two types was similar. Double-loop and double-wrap cerclage generated superior tension and resisted a greater load before loosening. Loop/twist cerclage had an intermediate initial tension but had the greatest resistance to loading. In the collapse test, the greater the initial tension, the more collapse could occur before the wire was loose. For all types of cerclage wire fixation, a reduction of diameter of the testing jig of more than 1% caused loosening. Double-loop and double-wrap cerclage provide greater compression of fragments and resist loads associated with weight-bearing better than the twist and loop methods. Loop/twist cerclage may have advantages because of their superior resistance to loading. All cerclage will loosen if fracture fragments collapse.

Multi-bit dark state memory: Double quantum dot as an electronic quantum memory

NASA Astrophysics Data System (ADS)

Aharon, Eran; Pozner, Roni; Lifshitz, Efrat; Peskin, Uri

2016-12-01

Quantum dot clusters enable the creation of dark states which preserve electrons or holes in a coherent superposition of dot states for a long time. Various quantum logic devices can be envisioned to arise from the possibility of storing such trapped particles for future release on demand. In this work, we consider a double quantum dot memory device, which enables the preservation of a coherent state to be released as multiple classical bits. Our unique device architecture uses an external gating for storing (writing) the coherent state and for retrieving (reading) the classical bits, in addition to exploiting an internal gating effect for the preservation of the coherent state.

Infrared laser driven double proton transfer. An optimal control theory study

NASA Astrophysics Data System (ADS)

Abdel-Latif, Mahmoud K.; Kühn, Oliver

2010-02-01

Laser control of ultrafast double proton transfer is investigated for a two-dimensional model system describing stepwise and concerted transfer pathways. The pulse design has been done by employing optimal control theory in combination with the multiconfiguration time-dependent Hartree wave packet propagation. The obtained laser fields correspond to multiple pump-dump pulse sequences. Special emphasis is paid to the relative importance of stepwise and concerted transfer pathways for the driven wave packet and its dependence on the parameters of the model Hamiltonian as well as on the propagation time. While stepwise transfer is dominating in all cases considered, for high barrier systems concerted transfer proceeding via tunneling can make a contribution.

Optical double-image cryptography based on diffractive imaging with a laterally-translated phase grating.

PubMed

Chen, Wen; Chen, Xudong; Sheppard, Colin J R

2011-10-10

In this paper, we propose a method using structured-illumination-based diffractive imaging with a laterally-translated phase grating for optical double-image cryptography. An optical cryptosystem is designed, and multiple random phase-only masks are placed in the optical path. When a phase grating is laterally translated just before the plaintexts, several diffraction intensity patterns (i.e., ciphertexts) can be correspondingly obtained. During image decryption, an iterative retrieval algorithm is developed to extract plaintexts from the ciphertexts. In addition, security and advantages of the proposed method are analyzed. Feasibility and effectiveness of the proposed method are demonstrated by numerical simulation results. © 2011 Optical Society of America

CT arthrographic patterns in recurrent glenohumeral instability.

PubMed

Singson, R D; Feldman, F; Bigliani, L

1987-10-01

CT double-contrast arthrograms were performed on 54 shoulders in 53 patients with recurrent dislocation or subluxation to detect responsible underlying bony or soft-tissue abnormalities. Lesions of the anterior labrum in 52 (96%) of 54 cases and of the capsuloligamentous complex in 42 (78%) of 54 cases were the two most common abnormalities. There was no difference in the degree or number of labral lesions between subluxations and dislocations. However, more severe capsular lesions, subscapularis tendon tears, and widened subscapularis bursae were consistently found among patients with dislocations. Subsequent clinical, arthroscopic, and surgical findings showed that the use of CT double-contrast arthrograms resulted in improved definition of the multiple lesions associated with glenohumeral dysfunction.

Fixation of displaced subcapital femoral fractures. Compression screw fixation versus double divergent pins.

PubMed

Christie, J; Howie, C R; Armour, P C

1988-03-01

One hundred and twenty-seven consecutive patients with displaced subcapital fractures of the femoral neck (Garden Grade III or IV) all under 80 years of age and independently mobile, were randomly allocated to fixation with either double divergent pins or a single sliding screw-plate device. The incidence of non-union and infection in the sliding screw-plate group was significantly higher, and we believe that when internal fixation is considered appropriate multiple pinning should be used. Mobility after treatment was disappointing in about half of the patients, and we feel that internal fixation can only be justified in patients who are physiologically well preserved and who maintain a high level of activity.

Persistent rupture terminations at a restraining bend from slip rates on the eastern Altyn Tagh fault

NASA Astrophysics Data System (ADS)

Elliott, A. J.; Oskin, M. E.; Liu-zeng, J.; Shao, Y.-X.

2018-05-01

Restraining double-bends along strike-slip faults inhibit or permit throughgoing ruptures depending on bend angle, length, and prior rupture history. Modeling predicts that for mature strike-slip faults in a regional stress regime characterized by simple shear, a restraining bend of >18° and >4 km length impedes propagating rupture. Indeed, natural evidence shows that the most recent rupture(s) of the Xorkoli section (90°-93°E) of the eastern Altyn Tagh fault (ATF) ended at large restraining bends. However, when multiple seismic cycles are considered in numerical dynamic rupture modeling, heterogeneous residual stresses enable some ruptures to propagate further, modulating whether the bends persistently serve as barriers. These models remain to be tested using observations of the cumulative effects of multiple earthquake ruptures. Here we investigate whether a large restraining double-bend on the ATF serves consistently as a barrier to rupture by measuring long-term slip rates around the terminus of its most recent surface rupture at the Aksay bend. Our results show a W-E decline in slip as the SATF enters the bend, as would be predicted from repeated rupture terminations there. Prior work demonstrated no Holocene slip on the central, most misoriented portion of the bend, while 19-79 m offsets suggest that multiple ruptures have occurred on the west side of the bend during the Holocene. Thus we conclude the gradient in the SATF's slip rate results from the repeated termination of earthquake ruptures there. However, a finite slip rate east of the bend represents the transmission of some slip, suggesting that a small fraction of ruptures may fully traverse or jump the double-bend. This agreement between natural observations of slip accumulation and multi-cycle models of fault rupture enables us to translate observed slip rates into insight about the dynamic rupture process of individual earthquakes as they encounter geometric complexities along faults.

Effects of a pulsed electromagnetic therapy on multiple sclerosis fatigue and quality of life: a double-blind, placebo controlled trial.

PubMed

Lappin, Martha S; Lawrie, Fraser Wilson; Richards, Todd L; Kramer, Eric D

2003-01-01

There is a growing literature on the biological and clinical effects of pulsed electromagnetic fields. Some studies suggest that electromagnetic therapies may be useful in the treatment of chronic illnesses. This study is a follow-up to a placebo controlled pilot study in which multiple sclerosis (MS) patients exposed to weak, extremely low frequency pulsed electromagnetic fields showed significant improvements on a composite symptom measure. To evaluate the effects of a pulsed electromagnetic therapy on MS related fatigue, spasticity, bladder control, and overall quality of life. A multi-site, double-blind, placebo controlled, crossover trial. Each subject received 4 weeks of the active and placebo treatments separated by a 2-week washout period. The University of Washington Medical Center in Seattle Wash, the Neurology Center of Fairfax in Fairfax, Va, and the headquarters of the Multiple Sclerosis Association of America in Cherry Hill, NJ. 117 patients with clinically definite MS. Daily exposure to a small, portable pulsing electromagnetic field generator. The MS Quality of Life Inventory (MSQLI) was used to assess changes in fatigue, bladder control, spasticity, and a quality of life composite. Paired t-tests were used to assess treatment differences in the 117 subjects (81% of the initial sample) who completed both treatment sessions. Improvements in fatigue and overall quality of life were significantly greater on the active device. There were no treatment effects for bladder control and a disability composite, and mixed results for spasticity. Evidence from this randomized, double-bind, placebo controlled trial is consistent with results from smaller studies suggesting that exposure to pulsing, weak electromagnetic fields can alleviate symptoms of MS. The clinical effects were small, however, and need to be replicated. Additional research is also needed to examine the possibility that ambulatory patients and patients taking interferons for their MS may be most responsive to this kind of treatment.

Multiple-labelling immunoEM using different sizes of colloidal gold: alternative approaches to test for differential distribution and colocalization in subcellular structures.

PubMed

Mayhew, Terry M; Lucocq, John M

2011-03-01

Various methods for quantifying cellular immunogold labelling on transmission electron microscope thin sections are currently available. All rely on sound random sampling principles and are applicable to single immunolabelling across compartments within a given cell type or between different experimental groups of cells. Although methods are also available to test for colocalization in double/triple immunogold labelling studies, so far, these have relied on making multiple measurements of gold particle densities in defined areas or of inter-particle nearest neighbour distances. Here, we present alternative two-step approaches to codistribution and colocalization assessment that merely require raw counts of gold particles in distinct cellular compartments. For assessing codistribution over aggregate compartments, initial statistical evaluation involves combining contingency table and chi-squared analyses to provide predicted gold particle distributions. The observed and predicted distributions allow testing of the appropriate null hypothesis, namely, that there is no difference in the distribution patterns of proteins labelled by different sizes of gold particle. In short, the null hypothesis is that of colocalization. The approach for assessing colabelling recognises that, on thin sections, a compartment is made up of a set of sectional images (profiles) of cognate structures. The approach involves identifying two groups of compartmental profiles that are unlabelled and labelled for one gold marker size. The proportions in each group that are also labelled for the second gold marker size are then compared. Statistical analysis now uses a 2 × 2 contingency table combined with the Fisher exact probability test. Having identified double labelling, the profiles can be analysed further in order to identify characteristic features that might account for the double labelling. In each case, the approach is illustrated using synthetic and/or experimental datasets and can be refined to correct observed labelling patterns to specific labelling patterns. These simple and efficient approaches should be of more immediate utility to those interested in codistribution and colocalization in multiple immunogold labelling investigations.

3D-structured illumination microscopy reveals clustered DNA double-strand break formation in widespread γH2AX foci after high LET heavy-ion particle radiation.

PubMed

Hagiwara, Yoshihiko; Niimi, Atsuko; Isono, Mayu; Yamauchi, Motohiro; Yasuhara, Takaaki; Limsirichaikul, Siripan; Oike, Takahiro; Sato, Hiro; Held, Kathryn D; Nakano, Takashi; Shibata, Atsushi

2017-12-12

DNA double-strand breaks (DSBs) induced by ionising radiation are considered the major cause of genotoxic mutations and cell death. While DSBs are dispersed throughout chromatin after X-rays or γ-irradiation, multiple types of DNA damage including DSBs, single-strand breaks and base damage can be generated within 1-2 helical DNA turns, defined as a complex DNA lesion, after high Linear Energy Transfer (LET) particle irradiation. In addition to the formation of complex DNA lesions, recent evidence suggests that multiple DSBs can be closely generated along the tracks of high LET particle irradiation. Herein, by using three dimensional (3D)-structured illumination microscopy, we identified the formation of 3D widespread γH2AX foci after high LET carbon-ion irradiation. The large γH2AX foci in G 2 -phase cells encompassed multiple foci of replication protein A (RPA), a marker of DSBs undergoing resection during homologous recombination. Furthermore, we demonstrated by 3D analysis that the distance between two individual RPA foci within γH2AX foci was approximately 700 nm. Together, our findings suggest that high LET heavy-ion particles induce clustered DSB formation on a scale of approximately 1 μm 3 . These closely localised DSBs are considered to be a risk for the formation of chromosomal rearrangement after heavy-ion irradiation.

LC/MS/MS quantitation assay for pharmacokinetics of naringenin and double peaks phenomenon in rats plasma.

PubMed

Ma, Yan; Li, Peibo; Chen, Dawei; Fang, Tiezheng; Li, Haitian; Su, Weiwei

2006-01-13

A highly sensitive and specific electrospray ionization (ESI) liquid chromatography-tandem mass spectrometry (LC/MS/MS) method for quantitation of naringenin (NAR) and an explanation for the double peaks phenomenon was developed and validated. NAR was extracted from rat plasma and tissues along with the internal standard (IS), hesperidin, with ethyl acetate. The analytes were analyzed in the multiple-reaction-monitoring (MRM) mode as the precursor/product ion pair of m/z 273.4/151.3 for NAR and m/z 611.5/303.3 for the IS. The assay was linear over the concentration range of 5-2500 ng/mL. The lower limit quantification was 5 ng/mL, available for plasma pharmacokinetics of NAR in rats. Accuracy in within- and between-run precisions showed good reproducibility. When NAR was administered orally, only little and predominantly its glucuronidation were into circulation in the plasma. There existed double peaks phenomenon in plasma concentration-time curve leading to the relatively slow elimination of NAR in plasma. The results showed that there was a linear relationship between the AUC of total NAR and dosages. And the double peaks are mainly due to enterohepatic circulation.

Selectivity of Electronic Coherence and Attosecond Ionization Delays in Strong-Field Double Ionization

NASA Astrophysics Data System (ADS)

Kobayashi, Yuki; Reduzzi, Maurizio; Chang, Kristina F.; Timmers, Henry; Neumark, Daniel M.; Leone, Stephen R.

2018-06-01

Experiments are presented on real-time probing of coherent electron dynamics in xenon initiated by strong-field double ionization. Attosecond transient absorption measurements allow for characterization of electronic coherences as well as relative ionization timings in multiple electronic states of Xe+ and Xe2 + . A high degree of coherence g =0.4 is observed between P3 2 0-P3 0 0 of Xe2 + , whereas for other possible pairs of states the coherences are below the detection limits of the experiments. A comparison of the experimental results with numerical simulations based on an uncorrelated electron-emission model shows that the coherences produced by strong-field double ionization are more selective than predicted. Surprisingly short ionization time delays, 0.85 fs, 0.64 fs, and 0.75 fs relative to Xe+ formation, are also measured for the P2 3 , P0 3 , and P1 3 states of Xe2 + , respectively. Both the unpredicted selectivity in the formation of coherence and the subfemtosecond time delays of specific states provide new insight into correlated electron dynamics in strong-field double ionization.

Testing the Presence of Multiple Photometric Components in Nearby Early-type Galaxies using SDSS

NASA Astrophysics Data System (ADS)

Oh, Semyeong; Greene, Jenny E.; Lackner, Claire N.

2017-02-01

We investigate two-dimensional image decomposition of nearby, morphologically selected early-type galaxies (ETGs). We are motivated by recent observational evidence of significant size growth of quiescent galaxies and theoretical development advocating a two-phase formation scenario for ETGs. We find that a significant fraction of nearby ETGs show changes in isophotal shape that require multi-component models. The characteristic sizes of the inner and outer component are ˜3 and ˜15 kpc. The inner component lies on the mass-size relation of ETGs at z ˜ 0.25-0.75, while the outer component tends to be more elliptical and hints at a stochastic buildup process. We find real physical differences between single- and double-component ETGs, with double-component galaxies being younger and more metal-rich. The fraction of double-component ETGs increases with increasing σ and decreases in denser environments. We hypothesize that double-component systems were able to accrete gas and small galaxies until later times, boosting their central densities, building up their outer parts, and lowering their typical central ages. In contrast, the oldest galaxies, perhaps due to residing in richer environments, have no remaining hints of their last accretion episode.

Laser-induced periodic surface structures on titanium upon single- and two-color femtosecond double-pulse irradiation.

PubMed

Höhm, Sandra; Rosenfeld, Arkadi; Krüger, Jörg; Bonse, Jörn

2015-10-05

Single- and two-color double-fs-pulse experiments were performed on titanium to study the dynamics of the formation of laser-induced periodic surface structures (LIPSS). A Mach-Zehnder inter-ferometer generated polarization controlled (parallel or cross-polarized) double-pulse sequences in two configurations - either at 800 nm only, or at 400 and 800 nm wavelengths. The inter-pulse delays of the individual 50-fs pulses ranged up to some tens of picoseconds. Multiple of these single- or two-color double-fs-pulse sequences were collinearly focused by a spherical mirror to the sample surface. In both experimental configurations, the peak fluence of each individual pulse was kept below its respective ablation threshold and only the joint action of both pulses lead to the formation of LIPSS. Their resulting characteristics were analyzed by scanning electron microscopy and the periods were quantified by Fourier analyses. The LIPSS periods along with the orientation allow a clear identification of the pulse which dominates the energy coupling to the material. A plasmonic model successfully explains the delay-dependence of the LIPSS on titanium and confirms the importance of the ultrafast energy deposition stage for LIPSS formation.

RNAHelix: computational modeling of nucleic acid structures with Watson-Crick and non-canonical base pairs.

PubMed

Bhattacharyya, Dhananjay; Halder, Sukanya; Basu, Sankar; Mukherjee, Debasish; Kumar, Prasun; Bansal, Manju

2017-02-01

Comprehensive analyses of structural features of non-canonical base pairs within a nucleic acid double helix are limited by the availability of a small number of three dimensional structures. Therefore, a procedure for model building of double helices containing any given nucleotide sequence and base pairing information, either canonical or non-canonical, is seriously needed. Here we describe a program RNAHelix, which is an updated version of our widely used software, NUCGEN. The program can regenerate duplexes using the dinucleotide step and base pair orientation parameters for a given double helical DNA or RNA sequence with defined Watson-Crick or non-Watson-Crick base pairs. The original structure and the corresponding regenerated structure of double helices were found to be very close, as indicated by the small RMSD values between positions of the corresponding atoms. Structures of several usual and unusual double helices have been regenerated and compared with their original structures in terms of base pair RMSD, torsion angles and electrostatic potentials and very high agreements have been noted. RNAHelix can also be used to generate a structure with a sequence completely different from an experimentally determined one or to introduce single to multiple mutation, but with the same set of parameters and hence can also be an important tool in homology modeling and study of mutation induced structural changes.

Holographic Reciprocity Law Failure, with Applications to the Three-Dimensional Display of Medical Data

NASA Astrophysics Data System (ADS)

Johnson, Kristina Mary

In 1973 the computerized tomography (CT) scanner revolutionized medical imaging. This machine can isolate and display in two-dimensional cross-sections, internal lesions and organs previously impossible to visualize. The possibility of three-dimensional imaging however is not yet exploited by present tomographic systems. Using multiple-exposure holography, three-dimensional displays can be synthesizing from two-dimensional CT cross -sections. A multiple-exposure hologram is an incoherent superposition of many individual holograms. Intuitively it is expected that holograms recorded with equal energy will reconstruct images with equal brightness. It is found however, that holograms recorded first are brighter than holograms recorded later in the superposition. This phenomena is called Holographic Reciprocity Law Failure (HRLF). Computer simulations of latent image formation in multiple-exposure holography are one of the methods used to investigate HRLF. These simulations indicate that it is the time between individual exposures in the multiple -exposure hologram that is responsible for HRLF. This physical parameter introduces an asymmetry into the latent image formation process that favors the signal of previously recorded holograms over holograms recorded later in the superposition. The origin of this asymmetry lies in the dynamics of latent image formation, and in particular in the decay of single-atom latent image specks, which have lifetimes that are short compared to typical times between exposures. An analytical model is developed for a double exposure hologram that predicts a decrease in the brightness of the second exposure as compared to the first exposure as the time between exposures increases. These results are consistent with the computer simulations. Experiments investigating the influence of this parameter on the diffraction efficiency of reconstructed images in a double exposure hologram are also found to be consistent with the computer simulations and analytical results. From this information, two techniques are presented that correct for HRLF, and succeed in reconstructing multiple holographic images of CT cross-sections with equal brightness. The multiple multiple-exposure hologram is a new hologram that increases the number of equally bright images that can be superimposed on one photographic plate.

In search of real autonomy for fertility patients.

PubMed

Johnston, Josephine; Gusmano, Michael K; Patrizio, Pasquale

2015-07-01

Nearly one in eight infants in the United States is born preterm. A variety of factors are associated with preterm birth, including multiplicity. In the United States fertility treatments are currently associated with high rates of multiplicity, but these rates could be reduced significantly if changes can be made to fertility treatment policy and practice. These include reducing the financial pressure on patients to prioritize pregnancy chances over safety by expanding insurance coverage and altering the way we calculate success rates and insurance benefits so that two consecutive single embryo transfers is equivalent to one double embryo transfer.

Fast REDOR with CPMG multiple-echo acquisition

NASA Astrophysics Data System (ADS)

Hung, Ivan; Gan, Zhehong

2014-01-01

Rotational-Echo Double Resonance (REDOR) is a widely used experiment for distance measurements in solids. The conventional REDOR experiment measures the signal dephasing from hetero-nuclear recoupling under magic-angle spinning (MAS) in a point by point manner. A modified Carr-Purcell Meiboom-Gill (CPMG) multiple-echo scheme is introduced for fast REDOR measurement. REDOR curves are measured from the CPMG echo amplitude modulation under dipolar recoupling. The real time CPMG-REDOR experiment can speed up the measurement by an order of magnitude. The effects from hetero-nuclear recoupling, the Bloch-Siegert shift and echo truncation to the signal acquisition are discussed and demonstrated.

Notch sensitivity and stress redistribution in three ceramic-matrix composites

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

Mackin, T.J.; He, M.Y.; Evans, A.G.

Fiber-reinforced ceramic-matrix composites (CMCs) depend upon inelastic mechanisms to diffuse stress concentrations associated with holes, notches, and cracks. These mechanisms consist of fiber debonding and pullout, multiple matrix cracking, and shear band formation. In order to understand these effects, experiments have bee conducted on several double-edge-notched CMCs that exhibit different stress redistribution mechanisms. Stresses have been measured an d mechanisms identified by using a combination of methods including X0-ray imaging, edge replication, and thermoelastic analysis. Multiple matrix cracking was found to be the most effective stress redistribution mechanism.

Experiences in autotuning matrix multiplication for energy minimization on GPUs

DOE PAGES

Anzt, Hartwig; Haugen, Blake; Kurzak, Jakub; ...

2015-05-20

In this study, we report extensive results and analysis of autotuning the computationally intensive graphics processing units kernel for dense matrix–matrix multiplication in double precision. In contrast to traditional autotuning and/or optimization for runtime performance only, we also take the energy efficiency into account. For kernels achieving equal performance, we show significant differences in their energy balance. We also identify the memory throughput as the most influential metric that trades off performance and energy efficiency. Finally, as a result, the performance optimal case ends up not being the most efficient kernel in overall resource use.

Cascaded-cladding-pumped cascaded Raman fiber amplifier.

PubMed

Jiang, Huawei; Zhang, Lei; Feng, Yan

2015-06-01

The conversion efficiency of double-clad Raman fiber laser is limited by the cladding-to-core area ratio. To get high conversion efficiency, the inner-cladding-to-core area ratio has to be less than about 8, which limits the brightness enhancement. To overcome the problem, a cascaded-cladding-pumped cascaded Raman fiber laser with multiple-clad fiber as the Raman gain medium is proposed. A theoretical model of Raman fiber amplifier with multiple-clad fiber is developed, and numerical simulation proves that the proposed scheme can improve the conversion efficiency and brightness enhancement of cladding pumped Raman fiber laser.

Resonance Frequency Tuning of a Double Ring Resonator in GaInAsP/InP: Experiment and Simulation

NASA Astrophysics Data System (ADS)

Rabus, Dominik Gerhard; Hamacher, Michael; Heidrich, Helmut

2002-02-01

A racetrack shaped double ring resonator (DRR) filter is demonstrated with radii of 200 μm. The double ring resonator contains two -3 dB multimode interference (MMI) couplers for I/O coupling and a -13 dB codirectional coupler in between the rings. A free spectral range of 50 GHz has been realized. A simulation model has been developed to describe the DRR. As fabrication tolerances do not allow the realization of two identical rings with required nm-circumference accuracy in the resonator, a frequency alignment of the resonator is indispensable. The resonance frequency tuning is performed thermally using platinum resistors which have been placed on top of the waveguides in both rings. An on-off ratio increase has been achieved of more than 3 dB, resulting in a total on-off ratio larger than 18 dB. The frequency alignment is inevitable in the case of multiple coupled micro ring resonators.

Experimental investigation of current free double layers in helicon plasmas

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

Sahu, B. B.; Tarey, R. D.; Ganguli, A.

2014-02-15

The paper presents investigations of current free double layer (CFDL) that forms in helicon plasmas. In contrast to the other work reporting on the same subject, in the present investigations the double layer (DL) forms in a mirror-like magnetic field topology. The RF compensated Langmuir probe measurements show multiple DLs, which are in connection with, the abrupt fall of densities along with potential drop of about 24 V and 18 V. The DLs strengths (e ΔV{sub p})/(k T{sub e}) are about 9.5 and 6, and the corresponding widths are about 6 and 5 D lengths. The potential drop is nearly equal tomore » the thermal anisotropies between the two plasma regions forming the DL, which is present in the plateau region of mirror, unlike the earlier studies on the DL formation in the region of strong gradients in the magnetic field. Also, it presents a qualitative discussion on the mechanism of DL formation.« less

Experiments in dilution jet mixing effects of multiple rows and non-circular orifices

NASA Technical Reports Server (NTRS)

Holdeman, J. D.; Srinivasan, R.; Coleman, E. B.; Meyers, G. D.; White, C. D.

1985-01-01

Experimental and empirical model results are presented that extend previous studies of the mixing of single-sided and opposed rows of jets in a confined duct flow to include effects of non-circular orifices and double rows of jets. Analysis of the mean temperature data obtained in this investigation showed that the effects of orifice shape and double rows are significant only in the region close to the injection plane, provided that the orifices are symmetric with respect to the main flow direction. The penetration and mixing of jets from 45-degree slanted slots is slightly less than that from equivalent-area symmetric orifices. The penetration from 2-dimensional slots is similar to that from equivalent-area closely-spaced rows of holes, but the mixing is slower for the 2-D slots. Calculated mean temperature profiles downstream of jets from non-circular and double rows of orifices, made using an extension developed for a previous empirical model, are shown to be in good agreement with the measured distributions.

Experiments in dilution jet mixing - Effects of multiple rows and non-circular orifices

NASA Technical Reports Server (NTRS)

Holdeman, J. D.; Srinivasan, R.; Coleman, E. B.; Meyers, G. D.; White, C. D.

1985-01-01

Experimental and empirical model results are presented that extend previous studies of the mixing of single-sided and opposed rows of jets in a confined duct flow to include effects of non-circular orifices and double rows of jets. Analysis of the mean temperature data obtained in this investigation showed that the effects of orifice shape and double rows are significant only in the region close to the injection plane, provided that the orifices are symmetric with respect to the main flow direction. The penetration and mixing of jets from 45-degree slanted slots is slightly less than that from equivalent-area symmetric orifices. The penetration from two-dimensional slots is similar to that from equivalent-area closely-spaced rows of holes, but the mixing is slower for the 2-D slots. Calculated mean temperature profiles downstream of jets from non-circular and double rows of orifices, made using an extension developed for a previous empirical model, are shown to be in good agreement with the measured distributions.

PandaX-III neutrinoless double beta decay experiment

NASA Astrophysics Data System (ADS)

Wang, Shaobo; PandaX-III Collaboration

2017-09-01

The PandaX-III experiment uses high pressure Time Projection Chambers (TPCs) to search for neutrinoless double-beta decay of Xe-136 with high energy resolution and sensitivity at the China Jin-Ping underground Laboratory II (CJPL-II). Fine-pitch Microbulk Micromegas will be used for charge amplification and readout in order to reconstruct both the energy and track of the neutrinoless double-beta decay event. In the first phase of the experiment, the detector, which contains 200 kg of 90% Xe-136 enriched gas operated at 10 bar, will be immersed in a large water tank to ensure 5 m of water shielding. For the second phase, a ton-scale experiment with multiple TPCs will be constructed to improve the detection probability and sensitivity. A 20-kg scale prototype TPC with 7 Micromegas modules has been built to optimize the design of Micromegas readout module, study the energy calibration of TPC and develop algorithm of 3D track reconstruction.

Simultaneous determination of creatinine and creatine in human serum by double-spike isotope dilution liquid chromatography-tandem mass spectrometry (LC-MS/MS) and gas chromatography-mass spectrometry (GC-MS).

PubMed

Fernández-Fernández, Mario; Rodríguez-González, Pablo; Añón Álvarez, M Elena; Rodríguez, Felix; Menéndez, Francisco V Álvarez; García Alonso, J Ignacio

2015-04-07

This work describes the first multiple spiking isotope dilution procedure for organic compounds using (13)C labeling. A double-spiking isotope dilution method capable of correcting and quantifying the creatine-creatinine interconversion occurring during the analytical determination of both compounds in human serum is presented. The determination of serum creatinine may be affected by the interconversion between creatine and creatinine during sample preparation or by inefficient chemical separation of those compounds by solid phase extraction (SPE). The methodology is based on the use differently labeled (13)C analogues ((13)C1-creatinine and (13)C2-creatine), the measurement of the isotopic distribution of creatine and creatinine by liquid chromatography-tandem mass spectrometry (LC-MS/MS) and the application of multiple linear regression. Five different lyophilized serum-based controls and two certified human serum reference materials (ERM-DA252a and ERM-DA253a) were analyzed to evaluate the accuracy and precision of the proposed double-spike LC-MS/MS method. The methodology was applied to study the creatine-creatinine interconversion during LC-MS/MS and gas chromatography-mass spectrometry (GC-MS) analyses and the separation efficiency of the SPE step required in the traditional gas chromatography-isotope dilution mass spectrometry (GC-IDMS) reference methods employed for the determination of serum creatinine. The analysis of real serum samples by GC-MS showed that creatine-creatinine separation by SPE can be a nonquantitative step that may induce creatinine overestimations up to 28% in samples containing high amounts of creatine. Also, a detectable conversion of creatine into creatinine was observed during sample preparation for LC-MS/MS. The developed double-spike LC-MS/MS improves the current state of the art for the determination of creatinine in human serum by isotope dilution mass spectrometry (IDMS), because corrections are made for all the possible errors derived from the sample preparation step.

Enhanced provenance interpretation using combined U-Pb and (U-Th)/He double dating of detrital zircon grains from lower Miocene strata, proximal Gulf of Mexico Basin, North America

NASA Astrophysics Data System (ADS)

Xu, Jie; Stockli, Daniel F.; Snedden, John W.

2017-10-01

Detrital zircon U-Pb analysis is an effective approach for investigating sediment provenance by relating crystallization age to potential crystalline source terranes. Studies of large passive margin basins, such as the Gulf of Mexico Basin, that have received sediment from multiple terranes with non-unique crystallization ages or sedimentary strata, benefit from additional constraints to better elucidate provenance interpretation. In this study, U-Pb and (U-Th)/He double dating analyses on single zircons from the lower Miocene sandstones in the northern Gulf of Mexico Basin reveal a detailed history of sediment source evolution. U-Pb age data indicate that most zircon originated from five major crystalline provinces, including the Western Cordillera Arc (<250 Ma), the Appalachian-Ouachita orogen (500-260 Ma), the Grenville (1300-950 Ma) orogen, the Mid-Continent Granite-Rhyolite (1500-1300 Ma), and the Yavapai-Mazatzal (1800-1600 Ma) terranes as well as sparse Pan-African (700-500 Ma) and Canadian Shield (>1800 Ma) terranes. Zircon (U-Th)/He ages record tectonic cooling and exhumation in the U.S. since the Mesoproterozoic related to the Grenville to Laramide Orogenies. The combined crystallization and cooling information from single zircon double dating can differentiate volcanic and plutonic zircons. Importantly, the U-Pb-He double dating approach allows for the differentiation between multiple possible crystallization-age sources on the basis of their subsequent tectonic evolution. In particular, for Grenville zircons that are present in all of lower Miocene samples, four distinct zircon U-Pb-He age combinations are recognizable that can be traced back to four different possible sources. The integrated U-Pb and (U-Th)/He data eliminate some ambiguities and improves the provenance interpretation for the lower Miocene strata in the northern Gulf of Mexico Basin and illustrate the applicability of this approach for other large-scale basins to reconstruct sediment provenance and dispersal patterns.

Phase, current, absorbance, and photoluminescence of double and triple metal ion-doped synthetic and salmon DNA thin films

NASA Astrophysics Data System (ADS)

Chopade, Prathamesh; Reddy Dugasani, Sreekantha; Reddy Kesama, Mallikarjuna; Yoo, Sanghyun; Gnapareddy, Bramaramba; Lee, Yun Woo; Jeon, Sohee; Jeong, Jun-Ho; Park, Sung Ha

2017-10-01

We fabricated synthetic double-crossover (DX) DNA lattices and natural salmon DNA (SDNA) thin films, doped with 3 combinations of double divalent metal ions (M2+)-doped groups (Co2+-Ni2+, Cu2+-Co2+, and Cu2+-Ni2+) and single combination of a triple M2+-doped group (Cu2+-Ni2+-Co2+) at various concentrations of M2+ ([M2+]). We evaluated the optimum concentration of M2+ ([M2+]O) (the phase of M2+-doped DX DNA lattices changed from crystalline (up to ([M2+]O) to amorphous (above [M2+]O)) and measured the current, absorbance, and photoluminescent characteristics of multiple M2+-doped SDNA thin films. Phase transitions (visualized in phase diagrams theoretically as well as experimentally) from crystalline to amorphous for double (Co2+-Ni2+, Cu2+-Co2+, and Cu2+-Ni2+) and triple (Cu2+-Ni2+-Co2+) dopings occurred between 0.8 mM and 1.0 mM of Ni2+ at a fixed 0.5 mM of Co2+, between 0.6 mM and 0.8 mM of Co2+ at a fixed 3.0 mM of Cu2+, between 0.6 mM and 0.8 mM of Ni2+ at a fixed 3.0 mM of Cu2+, and between 0.6 mM and 0.8 mM of Co2+ at fixed 2.0 mM of Cu2+ and 0.8 mM of Ni2+, respectively. The overall behavior of the current and photoluminescence showed increments as increasing [M2+] up to [M2+]O, then decrements with further increasing [M2+]. On the other hand, absorbance at 260 nm showed the opposite behavior. Multiple M2+-doped DNA thin films can be used in specific devices and sensors with enhanced optoelectric characteristics and tunable multi-functionalities.

CCD Astrometric Measurements of WDS 04155+0611

NASA Astrophysics Data System (ADS)

Cao, Zhixin; Li, Junyao; Li, Jeff; Qu, Steve; Fene, Michael; Boyce, Grady; Boyce, Pat

2016-01-01

Twenty-two separations and position angle astrometric measurements were made of the multiple star system WDS 04155+0611. This system includes the pairs STTA 45 AB, H 6 98 AC, H 6 98 CD, and STU 18 CE. All measurements were compared with historical measurements from the Washington Double Star Catalog. Our astrometric results compare favorably with other recent observations.

Observations of compact radio nuclei in Cygnus A, Centaurus A, and other extended radio sources

NASA Technical Reports Server (NTRS)

Kellermann, K. I.; Clark, B. G.; Niell, A. E.; Shaffer, D. B.

1975-01-01

Observations of Cygnus A show a compact radio core 2 milliarcsec in extent oriented in the same direction as the extended components. Other large double- or multiple-component sources, including Centaurus A, have also been found to contain compact radio nuclei with angular sizes in the range 1-10 milliarcsec.

Method of making an InAsSb/InAsSbP diode lasers

DOEpatents

Razeghi, Manijeh

1997-01-01

InAsSb/InAsSbP/InAs Double Heterostructures (DH) and Separate Confinement Heterostructure Multiple Quantum Well (SCH-MQW) structures are taught wherein the ability to tune to a specific wavelength within 3 .mu.m to 5 .mu.m is possible by varying the ratio of As:Sb in the active layer.

Lattice Entertain You: Paper Modeling of the 14 Bravais Lattices on Youtube

ERIC Educational Resources Information Center

Sein, Lawrence T., Jr.; Sein, Sarajane E.

2015-01-01

A system for the construction of double-sided paper models of the 14 Bravais lattices, and important crystal structures derived from them, is described. The system allows the combination of multiple unit cells, so as to better represent the overall three-dimensional structure. Students and instructors can view the models in use on the popular…

Downy mildew of Double Knock Out® rose caused by Peronospora sparsa in Maryland

USDA-ARS?s Scientific Manuscript database

Roses are one of the most popular and economically important ornamental plants worldwide. In the last 17 years, Knock Out® roses (Rosa x 'Radtko') have been widely used in public and private gardens across the U.S. due to their disease resistance, self-cleaning, drought tolerance and multiple-bloomi...

The Design of Secondary Schools--A Case Study, Singapore.

ERIC Educational Resources Information Center

Liew Kok-Pun, Michael; And Others

Land scarcity dominates the thinking of school planners in Singapore. Techniques for optimizing the use of land for schools include (1) the construction of multi-storied or high-rise schools; (2) operation of a double-shift system and, in some cases, a triple-shift system; (3) multiple use of educational spaces; and (4) construction of several…

Why are we not evaluating multiple competing hypotheses in ecology and evolution?

PubMed Central

Avgar, Tal; Fryxell, John M.

2017-01-01

The use of multiple working hypotheses to gain strong inference is widely promoted as a means to enhance the effectiveness of scientific investigation. Only 21 of 100 randomly selected studies from the ecological and evolutionary literature tested more than one hypothesis and only eight tested more than two hypotheses. The surprising rarity of application of multiple working hypotheses suggests that this gap between theory and practice might reflect some fundamental issues. Here, we identify several intellectual and practical barriers that discourage us from using multiple hypotheses in our scientific investigation. While scientists have developed a number of ways to avoid biases, such as the use of double-blind controls, we suspect that few scientists are fully aware of the potential influence of cognitive bias on their decisions and they have not yet adopted many techniques available to overcome intellectual and practical barriers in order to improve scientific investigation. PMID:28280578

Realization of multiple orbital angular momentum modes simultaneously through four-dimensional antenna arrays.

PubMed

Sun, Chao; Yang, Shiwen; Chen, Yikai; Guo, Jixin; Qu, Shiwei

2018-01-09

Electromagnetic waves carrying orbital angular momentum (OAM) in radio frequency range have drawn great attention owing to its potential applications in increasing communication capacity. In this paper, both single-pole single-throw (SPST) switches and single-pole double-throw (SPDT) switches are designed and implemented. Optimal time sequence allows four-dimensional (4-D) circular antenna array to generate multiple OAM-carrying waves as well as enhance the field intensity of each OAM-carrying wave. A novel experimental platform is developed to measure the phase distribution when the transmitting antenna and the receiving antenna operate at different frequencies. The good agreement between the measurement and simulation results demonstrate that 4-D circular antenna array is able to generate multiple OAM modes simultaneously. Furthermore, the superiority of the 4-D circular antenna array in receiving and demodulating multiple OAM-carrying signals is validated through the filter and bit error rate (BER) simulations.

Multiple-reflection optical gas cell

DOEpatents

Matthews, Thomas G.

1983-01-01

A multiple-reflection optical cell for Raman or fluorescence gas analysis consists of two spherical mirrors positioned transverse to a multiple-pass laser cell in a confronting plane-parallel alignment. The two mirrors are of equal diameter but possess different radii of curvature. The spacing between the mirrors is uniform and less than half of the radius of curvature of either mirror. The mirror of greater curvature possesses a small circular portal in its center which is the effective point source for conventional F1 double lens collection optics of a monochromator-detection system. Gas to be analyzed is flowed into the cell and irradiated by a multiply-reflected composite laser beam centered between the mirrors of the cell. Raman or fluorescence radiation originating from a large volume within the cell is (1) collected via multiple reflections with the cell mirrors, (2) partially collimated and (3) directed through the cell portal in a geometric array compatible with F1 collection optics.

A study of the biological receptor activator of nuclear factor-kappaB ligand inhibitor, denosumab, in patients with multiple myeloma or bone metastases from breast cancer.

PubMed

Body, Jean-Jacques; Facon, Thierry; Coleman, Robert E; Lipton, Allan; Geurs, Filip; Fan, Michelle; Holloway, Donna; Peterson, Mark C; Bekker, Pirow J

2006-02-15

Receptor activator of nuclear factor-kappaB ligand (RANKL) is essential for the differentiation, function, and survival of osteoclasts, which play a key role in establishment and propagation of skeletal disease in patients with multiple myeloma or bone metastases as well as many other skeletal diseases. Denosumab (AMG 162), a fully human monoclonal antibody to RANKL, was developed to treat patients with skeletal diseases. This was a randomized, double-blind, double-dummy, active-controlled, multicenter study to determine the safety and efficacy of denosumab in patients with breast cancer (n = 29) or multiple myeloma (n = 25) with radiologically confirmed bone lesions. Patients received a single dose of either denosumab (0.1, 0.3, 1.0, or 3.0 mg/kg s.c.) or pamidronate (90 mg i.v.). Bone antiresorptive effect was assessed by changes in urinary and serum N-telopeptide levels. Pharmacokinetics of denosumab also were assessed. Following a single s.c. dose of denosumab, levels of urinary and serum N-telopeptide decreased within 1 day, and this decrease lasted through 84 days at the higher denosumab doses. Pamidronate also decreased bone turnover, but the effect diminished progressively through follow-up. Denosumab injections were well tolerated. Mean half-lives of denosumab were 33.3 and 46.3 days for the two highest dosages. A single s.c. dose of denosumab given to patients with multiple myeloma or bone metastases from breast cancer was well tolerated and reduced bone resorption for at least 84 days. The decrease in bone turnover markers was similar in magnitude but more sustained than with i.v. pamidronate.

Comparison of Two Types of Double-J Ureteral Stents that Differ in Diameter and the Existence of Multiple Side Holes along the Straight Portion in Malignant Ureteral Strictures

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

Song, Myung Gyu, E-mail: acube808@naver.com; Seo, Tae-Seok, E-mail: g1q1papa@korea.ac.kr; Lee, Chang Hee, E-mail: chlee86@korea.ac.kr

PurposeThis study was decided to evaluate the impact of diameter and the existences of multiple side holes along the straight portion of double-J ureteral stents (DJUS) on early dysfunction of stents placed for malignant ureteral strictures.MethodsBetween April 2007 and December 2011, 141 DJUSs were placed via a percutaneous nephrostomy (PCN) tract in 110 consecutive patients with malignant ureteral strictures. 7F DJUSs with multiple side holes in the straight portion were placed in 58 ureters of 43 patients (Group 1). 8F DJUSs with three side holes in the proximal 2-cm of the straight portion were placed in 83 ureters of 67more » patients (Group 2). The incidence of early DJUS dysfunction was compared between the two groups, and nephrostographic findings were evaluated in the cases of early dysfunction.ResultsEarly dysfunction of the DJUS was noted in 14 of 58 patients (24.1 %) in Group 1, which was significantly higher (p = 0.001) than in Group 2 in which only 1 of 83 patients (1.2 %) had early dysfunction of the DJUS. Nephrostographic findings of early dysfunction included dilatation of the pelvicalyceal system, filling defects in the ureteral stent, and no passage of contrast media into the urinary bladder.ConclusionsIn malignant ureteral strictures, multiple side holes in the straight portion of the 7-F DJUS seem to cause early dysfunction. The 8F DJUSs with three side holes in the proximal 2-cm of the straight portion may be superior at preventing early dysfunction.« less

Double trisomy (XXX+21 karyotype) in a six-year-old girl with down phenotype.

PubMed

Vergara-Mendez, Laura Daniela; Talero-Gutiérrez, Claudia; Velez-Van-Meerbeke, Alberto

2018-03-01

We describe a case of a six-year-old girl who presents multiple dysmorphic features characteristic of Down's syndrome. She has a significant general developmental delay, with a score that correspond to 32 months of developmental age. This delay is especially in language, with a very scant vocabulary. She communicates with some hand sign words or pointing, although her auditory responses in hearing test were normal. Two previous karyotype studies showed 47, XXX, +21 anomalies. This double trisomy is a rare condition described in isolated cases in the literature and none of these refers to the developmental aspects of these children (Balwan et al. 2008; Li et al. 2004; Park et al. 1995; Day et al. 1963).

Formation of laser-induced periodic surface structures on fused silica upon two-color double-pulse irradiation

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

Höhm, S.; Herzlieb, M.; Rosenfeld, A.

2013-12-16

The formation of laser-induced periodic surface structures (LIPSS) upon irradiation of fused silica with multiple irradiation sequences consisting of laser pulse pairs (50 fs single-pulse duration) of two different wavelengths (400 and 800 nm) is studied experimentally. Parallel polarized double-pulse sequences with a variable delay Δt between −10 and +10 ps and between the individual fs-laser pulses were used to investigate the LIPSS periods versus Δt. These two-color experiments reveal the importance of the ultrafast energy deposition to the silica surface by the first laser pulse for LIPSS formation. The second laser pulse subsequently reinforces the previously seeded spatial LIPSSmore » frequencies.« less

Hemispherical reflectance model for passive images in an outdoor environment.

PubMed

Kim, Charles C; Thai, Bea; Yamaoka, Neil; Aboutalib, Omar

2015-05-01

We present a hemispherical reflectance model for simulating passive images in an outdoor environment where illumination is provided by natural sources such as the sun and the clouds. While the bidirectional reflectance distribution function (BRDF) accurately produces radiance from any objects after the illumination, using the BRDF in calculating radiance requires double integration. Replacing the BRDF by hemispherical reflectance under the natural sources transforms the double integration into a multiplication. This reduces both storage space and computation time. We present the formalism for the radiance of the scene using hemispherical reflectance instead of BRDF. This enables us to generate passive images in an outdoor environment taking advantage of the computational and storage efficiencies. We show some examples for illustration.

Mutations in MYB3R1 and MYB3R4 Cause Pleiotropic Developmental Defects and Preferential Down-Regulation of Multiple G2/M-Specific Genes in Arabidopsis1[C][W

PubMed Central

Haga, Nozomi; Kobayashi, Kosuke; Suzuki, Takamasa; Maeo, Kenichiro; Kubo, Minoru; Ohtani, Misato; Mitsuda, Nobutaka; Demura, Taku; Nakamura, Kenzo; Jürgens, Gerd; Ito, Masaki

2011-01-01

R1R2R3-Myb proteins represent an evolutionarily conserved class of Myb family proteins important for cell cycle regulation and differentiation in eukaryotic cells. In plants, this class of Myb proteins are believed to regulate the transcription of G2/M phase-specific genes by binding to common cis-elements, called mitosis-specific activator (MSA) elements. In Arabidopsis (Arabidopsis thaliana), MYB3R1 and MYB3R4 act as transcriptional activators and positively regulate cytokinesis by activating the transcription of KNOLLE, which encodes a cytokinesis-specific syntaxin. Here, we show that the double mutation myb3r1 myb3r4 causes pleiotropic developmental defects, some of which are due to deficiency of KNOLLE whereas other are not, suggesting that multiple target genes are involved. Consistently, microarray analysis of the double mutant revealed altered expression of many genes, among which G2/M-specific genes showed significant overrepresentation of the MSA motif and a strong tendency to be down-regulated by the double mutation. Our results demonstrate, on a genome-wide level, the importance of the MYB3R-MSA pathway for regulating G2/M-specific transcription. In addition, MYB3R1 and MYB3R4 may have diverse roles during plant development by regulating G2/M-specific genes with various functions as well as genes possibly unrelated to the cell cycle. PMID:21862669

A Review on Spectral Amplitude Coding Optical Code Division Multiple Access

NASA Astrophysics Data System (ADS)

Kaur, Navpreet; Goyal, Rakesh; Rani, Monika

2017-06-01

This manuscript deals with analysis of Spectral Amplitude Coding Optical Code Division Multiple Access (SACOCDMA) system. The major noise source in optical CDMA is co-channel interference from other users known as multiple access interference (MAI). The system performance in terms of bit error rate (BER) degrades as a result of increased MAI. It is perceived that number of users and type of codes used for optical system directly decide the performance of system. MAI can be restricted by efficient designing of optical codes and implementing them with unique architecture to accommodate more number of users. Hence, it is a necessity to design a technique like spectral direct detection (SDD) technique with modified double weight code, which can provide better cardinality and good correlation property.

Damage threshold from large retinal spot size repetitive-pulse laser exposures.

PubMed

Lund, Brian J; Lund, David J; Edsall, Peter R

2014-10-01

The retinal damage thresholds for large spot size, multiple-pulse exposures to a Q-switched, frequency doubled Nd:YAG laser (532 nm wavelength, 7 ns pulses) have been measured for 100 μm and 500 μm retinal irradiance diameters. The ED50, expressed as energy per pulse, varies only weakly with the number of pulses, n, for these extended spot sizes. The previously reported threshold for a multiple-pulse exposure for a 900 μm retinal spot size also shows the same weak dependence on the number of pulses. The multiple-pulse ED50 for an extended spot-size exposure does not follow the n dependence exhibited by small spot size exposures produced by a collimated beam. Curves derived by using probability-summation models provide a better fit to the data.

The set of triple-resonance sequences with a multiple quantum coherence evolution period

NASA Astrophysics Data System (ADS)

Koźmiński, Wiktor; Zhukov, Igor

2004-12-01

The new pulse sequence building block that relies on evolution of heteronuclear multiple quantum coherences is proposed. The particular chemical shifts are obtained in multiple quadrature, using linear combinations of frequencies taken from spectra measured at different quantum levels. The pulse sequences designed in this way consist of small number of RF-pulses, are as short as possible, and could be applied for determination of coupling constants. The examples presented involve 2D correlations H NCO, H NCA, H N(CO) CA, and H(N) COCA via heteronuclear zero and double coherences, as well as 2D H NCOCA technique with simultaneous evolution of triple and three distinct single quantum coherences. Applications of the new sequences are presented for 13C, 15N-labeled ubiquitin.

Multiplicity counting from fission detector signals with time delay effects

NASA Astrophysics Data System (ADS)

Nagy, L.; Pázsit, I.; Pál, L.

2018-03-01

In recent work, we have developed the theory of using the first three auto- and joint central moments of the currents of up to three fission chambers to extract the singles, doubles and triples count rates of traditional multiplicity counting (Pázsit and Pál, 2016; Pázsit et al., 2016). The objective is to elaborate a method for determining the fissile mass, neutron multiplication, and (α, n) neutron emission rate of an unknown assembly of fissile material from the statistics of the fission chamber signals, analogous to the traditional multiplicity counting methods with detectors in the pulse mode. Such a method would be an alternative to He-3 detector systems, which would be free from the dead time problems that would be encountered in high counting rate applications, for example the assay of spent nuclear fuel. A significant restriction of our previous work was that all neutrons born in a source event (spontaneous fission) were assumed to be detected simultaneously, which is not fulfilled in reality. In the present work, this restriction is eliminated, by assuming an independent, identically distributed random time delay for all neutrons arising from one source event. Expressions are derived for the same auto- and joint central moments of the detector current(s) as in the previous case, expressed with the singles, doubles, and triples (S, D and T) count rates. It is shown that if the time-dispersion of neutron detections is of the same order of magnitude as the detector pulse width, as they typically are in measurements of fast neutrons, the multiplicity rates can still be extracted from the moments of the detector current, although with more involved calibration factors. The presented formulae, and hence also the performance of the proposed method, are tested by both analytical models of the time delay as well as with numerical simulations. Methods are suggested also for the modification of the method for large time delay effects (for thermalised neutrons).

Double layers and double wells in arbitrary degenerate plasmas

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

Akbari-Moghanjoughi, M.

Using the generalized hydrodynamic model, the possibility of variety of large amplitude nonlinear excitations is examined in electron-ion plasma with arbitrary electron degeneracy considering also the ion temperature effect. A new energy-density relation is proposed for plasmas with arbitrary electron degeneracy which reduces to the classical Boltzmann and quantum Thomas-Fermi counterparts in the extreme limits. The pseudopotential method is employed to find the criteria for existence of nonlinear structures such as solitons, periodic nonlinear structures, and double-layers for different cases of adiabatic and isothermal ion fluids for a whole range of normalized electron chemical potential, η{sub 0}, ranging from dilutemore » classical to completely degenerate electron fluids. It is observed that there is a Mach-speed gap in which no large amplitude localized or periodic nonlinear excitations can propagate in the plasma under consideration. It is further revealed that the plasma under investigation supports propagation of double-wells and double-layers the chemical potential and Mach number ranges of which are studied in terms of other plasma parameters. The Mach number criteria for nonlinear waves are shown to significantly differ for cases of classical with η{sub 0} < 0 and quantum with η{sub 0} > 0 regimes. It is also shown that the localized structure propagation criteria possess significant dissimilarities for plasmas with adiabatic and isothermal ions. Current research may be generalized to study the nonlinear structures in plasma containing positrons, multiple ions with different charge states, and charged dust grains.« less

Designing from Their Own Social Worlds: The Digital Story of Three African American Young Women

ERIC Educational Resources Information Center

Hall, Ted

2011-01-01

In this paper I examine the literacy work of three African American young women (through data drawn from a larger qualitative study), particularly their ways of knowing, such as double consciousness (Du Bois, 1989), and the multiple subject positions they occupy as they write themselves into a digitally created story. My analysis is guided by the…

Method of making an InAsSb/InAsSbP diode lasers

DOEpatents

Razeghi, M.

1997-08-19

InAsSb/InAsSbP/InAs Double Heterostructures (DH) and Separate Confinement Heterostructure Multiple Quantum Well (SCH-MQW) structures are taught wherein the ability to tune to a specific wavelength within 3 {micro}m to 5 {micro}m is possible by varying the ratio of As:Sb in the active layer. 9 figs.

Womanist Spirituality as a Response to the Racism-Sexism Double Bind in African American Women

ERIC Educational Resources Information Center

Williams, Carmen Braun; Wiggins, Marsha I.

2010-01-01

Many African American women begin counseling stigmatized by race and gender and may be targets of additional discrimination on the basis of sexual orientation, class, age, and other social variables. In this article, the authors discuss "womanist" spirituality as a means for African American women to cope with racism, sexism, and multiple social…

"Hits" (Not "Discussion Posts") Predict Student Success in Online Courses: A Double Cross-Validation Study

ERIC Educational Resources Information Center

Ramos, Cheryl; Yudko, Errol

2008-01-01

The efficacy of individual components of an online course on positive course outcome was examined via stepwise multiple regression analysis. Outcome was measured as the student's total score on all exams given during the course. The predictors were page hits, discussion posts, and discussion reads. The vast majority of the variance of outcome was…

Life Span as the Measure of Performance and Learning in a Business Gaming Simulation

ERIC Educational Resources Information Center

Thavikulwat, Precha

2012-01-01

This study applies the learning curve method of measuring learning to participants of a computer-assisted business gaming simulation that includes a multiple-life-cycle feature. The study involved 249 participants. It verified the workability of the feature and estimated the participants' rate of learning at 17.4% for every doubling of experience.…

A combined intervention of zinc, multiple micronutrients, and albendazole does not ameliorate environmental enteric dysfunction or stunting in rural Malawian children in a double-blind randomized controlled trial

USDA-ARS?s Scientific Manuscript database

Environmental enteric dysfunction (EED) and linear growth stunting affect many rural agrarian children in the developing world and contribute to the persistently high rates of stunting that are observed worldwide. Effective interventions to consistently ameliorate EED are lacking. We tested whether ...

Testing accelerometer rectification error caused by multidimensional composite inputs with double turntable centrifuge.

PubMed

Guan, W; Meng, X F; Dong, X M

2014-12-01

Rectification error is a critical characteristic of inertial accelerometers. Accelerometers working in operational situations are stimulated by composite inputs, including constant acceleration and vibration, from multiple directions. However, traditional methods for evaluating rectification error only use one-dimensional vibration. In this paper, a double turntable centrifuge (DTC) was utilized to produce the constant acceleration and vibration simultaneously and we tested the rectification error due to the composite accelerations. At first, we deduced the expression of the rectification error with the output of the DTC and a static model of the single-axis pendulous accelerometer under test. Theoretical investigation and analysis were carried out in accordance with the rectification error model. Then a detailed experimental procedure and testing results were described. We measured the rectification error with various constant accelerations at different frequencies and amplitudes of the vibration. The experimental results showed the distinguished characteristics of the rectification error caused by the composite accelerations. The linear relation between the constant acceleration and the rectification error was proved. The experimental procedure and results presented in this context can be referenced for the investigation of the characteristics of accelerometer with multiple inputs.

Self-aligned quadruple patterning using spacer on spacer integration optimization for N5

NASA Astrophysics Data System (ADS)

Thibaut, Sophie; Raley, Angélique; Mohanty, Nihar; Kal, Subhadeep; Liu, Eric; Ko, Akiteru; O'Meara, David; Tapily, Kandabara; Biolsi, Peter

2017-04-01

To meet scaling requirements, the semiconductor industry has extended 193nm immersion lithography beyond its minimum pitch limitation using multiple patterning schemes such as self-aligned double patterning, self-aligned quadruple patterning and litho-etch / litho etch iterations. Those techniques have been declined in numerous options in the last few years. Spacer on spacer pitch splitting integration has been proven to show multiple advantages compared to conventional pitch splitting approach. Reducing the number of pattern transfer steps associated with sacrificial layers resulted in significant decrease of cost and an overall simplification of the double pitch split technique. While demonstrating attractive aspects, SAQP spacer on spacer flow brings challenges of its own. Namely, material set selections and etch chemistry development for adequate selectivities, mandrel shape and spacer shape engineering to improve edge placement error (EPE). In this paper we follow up and extend upon our previous learning and proceed into more details on the robustness of the integration in regards to final pattern transfer and full wafer critical dimension uniformity. Furthermore, since the number of intermediate steps is reduced, one will expect improved uniformity and pitch walking control. This assertion will be verified through a thorough pitch walking analysis.

Impact of the release rate of magnesium ions in multiple emulsions (water-in-oil-in-water) containing BSA on the resulting physical properties and microstructure of soy protein gel.

PubMed

Zhu, Qiaomei; Zhao, Ling; Zhang, Hui; Saito, Masayoshi; Yin, Lijun

2017-04-01

The objective of present study was to prepare multiple water-in-oil-in-water (W/O/W) emulsions that exhibit different release rates of magnesium ions; and assess their utility as coagulants in improving tofu quality. W/O/W emulsions containing bovine serum albumin (BSA) and magnesium chloride (MgCl 2 ) were developed for controlled release applications. An increasing BSA concentration led to an increase in viscosity and droplet size of W/O/W double emulsions, as well as a decreased release rate of encapsulated Mg 2+ from emulsions. The gelation process of soy protein was simulated by conducting dynamic viscoelastic measurements. The rate constant (k) and saturated storage modulus (G' sat ) values of soy protein gel decreased as BSA concentration increased, suggesting that BSA could slow the release of magnesium ions from double emulsions. Confocal laser scanning microscopy (CLSM) results showed that increased concentration of BSA created a more homogeneous microstructure of soy protein gels with smaller pores within the gel network structure. Copyright © 2016 Elsevier Ltd. All rights reserved.

Building blocks of a multi-layer PET with time sequence photon interaction discrimination and double Compton camera

NASA Astrophysics Data System (ADS)

Ilisie, V.; Giménez-Alventosa, V.; Moliner, L.; Sánchez, F.; González, A. J.; Rodríguez-Álvarez, M. J.; Benlloch, J. M.

2018-07-01

Current PET detectors have a very low sensitivity, of the order of a few percent. One of the reasons is the fact that Compton interactions are rejected. If an event involves multiple Compton scattering and the total deposited energy lays within the photoelectric peak, then an energy-weighted centroid is the given output for the coordinates of the reconstructed interaction point. This introduces distortion in the final reconstructed image. The aim of our work is to prove that Compton events are a very rich source of additional information as one can improve the resolution of the detector and implicitly the final reconstructed image. This could be a real breakthrough for PET detector technology as one should be able to obtain better results with less patient radiation. Using a PET as a double Compton camera, by means of Compton cone matching i.e., Compton cones coming from the same event should be compatible, is applied to discard randoms, patient scattered events and also, to perform a correct matching among events with multiple coincidences. In order to fully benefit experimentally from Compton events using monolithic scintillators a multi-layer configuration is needed and a good time-of-flight resolution.

An Optimization of Inventory Demand Forecasting in University Healthcare Centre

NASA Astrophysics Data System (ADS)

Bon, A. T.; Ng, T. K.

2017-01-01

Healthcare industry becomes an important field for human beings nowadays as it concerns about one’s health. With that, forecasting demand for health services is an important step in managerial decision making for all healthcare organizations. Hence, a case study was conducted in University Health Centre to collect historical demand data of Panadol 650mg for 68 months from January 2009 until August 2014. The aim of the research is to optimize the overall inventory demand through forecasting techniques. Quantitative forecasting or time series forecasting model was used in the case study to forecast future data as a function of past data. Furthermore, the data pattern needs to be identified first before applying the forecasting techniques. Trend is the data pattern and then ten forecasting techniques are applied using Risk Simulator Software. Lastly, the best forecasting techniques will be find out with the least forecasting error. Among the ten forecasting techniques include single moving average, single exponential smoothing, double moving average, double exponential smoothing, regression, Holt-Winter’s additive, Seasonal additive, Holt-Winter’s multiplicative, seasonal multiplicative and Autoregressive Integrated Moving Average (ARIMA). According to the forecasting accuracy measurement, the best forecasting technique is regression analysis.

Detection of cerebral amyloid angiopathy by 3-T magnetic resonance imaging and amyloid positron emission tomography in a patient with subcortical ischaemic vascular dementia.

PubMed

Kida, Hirotaka; Satoh, Masayuki; Ii, Yuichiro; Fukuyama, Hidenao; Maeda, Masayuki; Tomimoto, Hidekazu

2017-01-01

The patient was an 81-year-old man who had been treated for hypertension for several decades. In 2012, he developed gait disturbance and mild amnesia. One year later, his gait disturbance worsened, and he developed urinary incontinence. Conventional brain magnetic resonance imaging using T 2 -weighted images and fluid-attenuated inversion recovery showed multiple lacunar infarctions. These findings fulfilled the diagnostic criteria for subcortical ischaemic vascular dementia. However, susceptibility weighted imaging showed multiple lobar microbleeds in the bilateral occipitoparietal lobes, and double inversion recovery and 3-D fluid-attenuated inversion recovery images on 3-T magnetic resonance imaging revealed cortical microinfarctions in the left parietal-temporo-occipito region. Pittsburgh compound B-positron emission tomography revealed diffuse uptake in the cerebral cortex. Therefore, we diagnosed the patient with subcortical ischaemic vascular dementia associated with Alzheimer's disease. The use of the double inversion recovery and susceptibility weighted imaging on 3-T magnetic resonance imaging may be a supplemental strategy for diagnosing cerebral amyloid angiopathy, which is closely associated with Alzheimer's disease. © 2016 The Authors. Psychogeriatrics © 2016 Japanese Psychogeriatric Society.

Multiple-image encryption based on double random phase encoding and compressive sensing by using a measurement array preprocessed with orthogonal-basis matrices

NASA Astrophysics Data System (ADS)

Zhang, Luozhi; Zhou, Yuanyuan; Huo, Dongming; Li, Jinxi; Zhou, Xin

2018-09-01

A method is presented for multiple-image encryption by using the combination of orthogonal encoding and compressive sensing based on double random phase encoding. As an original thought in optical encryption, it is demonstrated theoretically and carried out by using the orthogonal-basis matrices to build a modified measurement array, being projected onto the images. In this method, all the images can be compressed in parallel into a stochastic signal and be diffused to be a stationary white noise. Meanwhile, each single-image can be separately reestablished by adopting a proper decryption key combination through the block-reconstruction rather than the entire-rebuilt, for its costs of data and decryption time are greatly decreased, which may be promising both in multi-user multiplexing and huge-image encryption/decryption. Besides, the security of this method is characterized by using the bit-length of key, and the parallelism is investigated as well. The simulations and discussions are also made on the effects of decryption as well as the correlation coefficient by using a series of sampling rates, occlusion attacks, keys with various error rates, etc.

A pilot investigation of the hypoalgesic effects of transcutaneous electrical nerve stimulation upon low back pain in people with multiple sclerosis.

PubMed

Al-Smadi, J; Warke, K; Wilson, I; Cramp, A F L; Noble, G; Walsh, D M; Lowe-Strong, A S

2003-11-01

To investigate the hypoalgesic effects of transcutaneous electrical nerve stimulation (TENS) upon low back pain (LBP) in people with multiple sclerosis (MS). A randomized double-blind placebo controlled clinical pilot study. Fifteen people with MS were recruited and randomly allocated to one of the following groups under double blind conditions (n = 5 per group): TENS 1 (4 Hz, 200 micros), TENS 2 (110 Hz, 200 micros), placebo TENS. Treatment was applied for 45 minutes three times a week for six weeks with a four-week follow-up. The following outcome measures were taken at weeks 1, 6, and 10: visual analogue scale (VAS) (for current LBP, right leg pain, left leg pain); Leeds Multiple Sclerosis Quality of Life Questionnaire; Roland Morris Disability Questionnaire; Short Form-36 (SF-36) Version 1; and the McGill Pain Questionnaire (MPQ). VAS for current LBP, right and left leg pain were also taken before and after treatment, and once a week during the follow-up period. Analysis showed no statistically significant effects for any of the data. However, both active treatment groups showed a trend of improvement in the majority of the outcome measures. Active TENS was more effective than placebo TENS in decreasing VAS scores following each treatment although results were not statistically significant. Further work in this area is warranted and should include a larger number of participants in the form of a randomized controlled clinical trial to determine the efficacy of this modality.

3D-structured illumination microscopy reveals clustered DNA double-strand break formation in widespread γH2AX foci after high LET heavy-ion particle radiation

PubMed Central

Hagiwara, Yoshihiko; Niimi, Atsuko; Isono, Mayu; Yamauchi, Motohiro; Yasuhara, Takaaki; Limsirichaikul, Siripan; Oike, Takahiro; Sato, Hiro; Held, Kathryn D.; Nakano, Takashi; Shibata, Atsushi

2017-01-01

DNA double-strand breaks (DSBs) induced by ionising radiation are considered the major cause of genotoxic mutations and cell death. While DSBs are dispersed throughout chromatin after X-rays or γ-irradiation, multiple types of DNA damage including DSBs, single-strand breaks and base damage can be generated within 1–2 helical DNA turns, defined as a complex DNA lesion, after high Linear Energy Transfer (LET) particle irradiation. In addition to the formation of complex DNA lesions, recent evidence suggests that multiple DSBs can be closely generated along the tracks of high LET particle irradiation. Herein, by using three dimensional (3D)-structured illumination microscopy, we identified the formation of 3D widespread γH2AX foci after high LET carbon-ion irradiation. The large γH2AX foci in G2-phase cells encompassed multiple foci of replication protein A (RPA), a marker of DSBs undergoing resection during homologous recombination. Furthermore, we demonstrated by 3D analysis that the distance between two individual RPA foci within γH2AX foci was approximately 700 nm. Together, our findings suggest that high LET heavy-ion particles induce clustered DSB formation on a scale of approximately 1 μm3. These closely localised DSBs are considered to be a risk for the formation of chromosomal rearrangement after heavy-ion irradiation. PMID:29312614

Prospects of pharmaceuticals and biopharmaceuticals loaded microparticles prepared by double emulsion technique for controlled delivery

PubMed Central

Giri, Tapan Kumar; Choudhary, Chhatrapal; Ajazuddin; Alexander, Amit; Badwaik, Hemant; Tripathi, Dulal Krishna

2012-01-01

Several methods and techniques are potentially useful for the preparation of microparticles in the field of controlled drug delivery. The type and the size of the microparticles, the entrapment, release characteristics and stability of drug in microparticles in the formulations are dependent on the method used. One of the most common methods of preparing microparticles is the single emulsion technique. Poorly soluble, lipophilic drugs are successfully retained within the microparticles prepared by this method. However, the encapsulation of highly water soluble compounds including protein and peptides presents formidable challenges to the researchers. The successful encapsulation of such compounds requires high drug loading in the microparticles, prevention of protein and peptide degradation by the encapsulation method involved and predictable release, both rate and extent, of the drug compound from the microparticles. The above mentioned problems can be overcome by using the double emulsion technique, alternatively called as multiple emulsion technique. Aiming to achieve this various techniques have been examined to prepare stable formulations utilizing w/o/w, s/o/w, w/o/o, and s/o/o type double emulsion methods. This article reviews the current state of the art in double emulsion based technologies for the preparation of microparticles including the investigation of various classes of substances that are pharmaceutically and biopharmaceutically active. PMID:23960828

Responding to the call for globalization in nursing education: the implementation of the transatlantic double-degree program.

PubMed

Hornberger, Cynthia A; Erämaa, Sirkka; Helembai, Kornélia; McCartan, Patrick J; Turtiainen, Tarja

2014-01-01

Increased demand for nurses worldwide has highlighted the need for a flexible nursing workforce eligible for licensure in multiple countries. Nursing's curricular innovation mirrors the call for reform within higher education including globalization of curricula (E. J. S. Hovenga, 2004; D. Nayyar, 2008; B. J. G. Wood, S. M. Tapsall, & G. N. Soutar, 2005), increased opportunities for student mobility exchanges, dialogue between different academic traditions, and mutual understanding and transparency between universities (J. González & R. Wagenaar, 2005). The European Union (EU) and United States have combined efforts to achieve these objectives by creating the Atlantis program in 2007 (U.S. Department of Education, 2011). This article describes experiences of four nursing programs participating in an Atlantis project to develop a double-degree baccalaureate program for undergraduate nursing students. Early learnings include increasing awareness and appreciation of essential curricular and performance competencies of the baccalaureate-prepared professional nurse. Challenges include language competency; variations in curriculum, cultural norms, student expectations, and learning assessment; and philosophical differences regarding first-level professional nurse preparation as specialist versus generalist. The Transatlantic Double Degree program has successfully implemented the double-degree program. Members have gained valuable insights into key issues surrounding the creation of a more uniform, yet flexible, educational standard between our countries. © 2014.

Globally optimal, minimum stored energy, double-doughnut superconducting magnets.

PubMed

Tieng, Quang M; Vegh, Viktor; Brereton, Ian M

2010-01-01

The use of the minimum stored energy current density map-based methodology of designing closed-bore symmetric superconducting magnets was described recently. The technique is further developed to cater for the design of interventional-type MRI systems, and in particular open symmetric magnets of the double-doughnut configuration. This extends the work to multiple magnet domain configurations. The use of double-doughnut magnets in MRI scanners has previously been hindered by the ability to deliver strong magnetic fields over a sufficiently large volume appropriate for imaging, essentially limiting spatial resolution, signal-to-noise ratio, and field of view. The requirement of dedicated interventional space restricts the manner in which the coils can be arranged and placed. The minimum stored energy optimal coil arrangement ensures that the field strength is maximized over a specific region of imaging. The design method yields open, dual-domain magnets capable of delivering greater field strengths than those used prior to this work, and at the same time it provides an increase in the field-of-view volume. Simulation results are provided for 1-T double-doughnut magnets with at least a 50-cm 1-ppm (parts per million) field of view and 0.7-m gap between the two doughnuts. Copyright (c) 2009 Wiley-Liss, Inc.

Handling nonresponse in surveys: analytic corrections compared with converting nonresponders.

PubMed

Jenkins, Paul; Earle-Richardson, Giulia; Burdick, Patrick; May, John

2008-02-01

A large health survey was combined with a simulation study to contrast the reduction in bias achieved by double sampling versus two weighting methods based on propensity scores. The survey used a census of one New York county and double sampling in six others. Propensity scores were modeled as a logistic function of demographic variables and were used in conjunction with a random uniform variate to simulate response in the census. These data were used to estimate the prevalence of chronic disease in a population whose parameters were defined as values from the census. Significant (p < 0.0001) predictors in the logistic function included multiple (vs. single) occupancy (odds ratio (OR) = 1.3), bank card ownership (OR = 2.1), gender (OR = 1.5), home ownership (OR = 1.3), head of household's age (OR = 1.4), and income >$18,000 (OR = 0.8). The model likelihood ratio chi-square was significant (p < 0.0001), with the area under the receiver operating characteristic curve = 0.59. Double-sampling estimates were marginally closer to population values than those from either weighting method. However, the variance was also greater (p < 0.01). The reduction in bias for point estimation from double sampling may be more than offset by the increased variance associated with this method.

Sustained delivery of salbutamol and beclometasone from spray-dried double emulsions.

PubMed

Learoyd, Tristan P; Burrows, Jane L; French, Eddie; Seville, Peter C

2010-01-01

The sustained delivery of multiple agents to the lung offers potential benefits to patients. This study explores the preparation of highly respirable dual-loaded spray-dried double emulsions. Spray-dried powders were produced from water-in-oil-in-water (w/o/w) double emulsions, containing salbutamol sulphate and/or beclometasone dipropionate in varying phases. The double emulsions contained the drug release modifier polylactide co-glycolide (PLGA 50 : 50) in the intermediate organic phase of the original micro-emulsion and low molecular weight chitosan (Mw<190 kDa: emulsion stabilizer) and leucine (aerosolization enhancer) in the tertiary aqueous phase. Following spray-drying resultant powders were physically characterized: with in vitro aerosolization performance and drug release investigated using a Multi-Stage Liquid Impinger and modified USP II dissolution apparatus, respectively. Powders generated were of a respirable size exhibiting emitted doses of over 95% and fine particle fractions of up to 60% of the total loaded dose. Sustained drug release profiles were observed during dissolution for powders containing agents in the primary aqueous and secondary organic phases of the original micro-emulsion; the burst release of agents was witnessed from the tertiary aqueous phase. The novel spray-dried emulsions from this study would be expected to deposit and display sustained release character in the lung.

Production of W/O/W (water-in-oil-in-water) multiple emulsions: droplet breakup and release of water.

PubMed

Schuch, Anna; Deiters, Philipp; Henne, Julius; Köhler, Karsten; Schuchmann, Heike P

2013-07-15

We investigate breakup of W/O/W double emulsion droplets at high viscosity ratios and coalescence of inner water droplets dependent on the dispersed phase content (DPC) of the inner emulsion. The rheological analyses of the inner emulsions confirm the behavior expected from literature - increasing viscosity with increasing DPC and elastic behavior for high DPC. The resulting droplet sizes seem to be influenced only by the viscosity ratio calculated using the viscosity of the inner emulsion. An influence of the elastic properties of the inner emulsions could not be observed. Moreover, breakup of double emulsion droplets seems to follow the same rules as breakup of Newtonian droplets. In the second part of the paper we focus on the release of water from double emulsions by coalescence. A direct correlation between resulting double emulsion droplet sizes and encapsulation efficiency was found for each system. The initial inner dispersed phase content has a big influence on the release rate. This can partly be explained by the influence of the dispersed phase content on collision rate. Moreover, it was found that for high internal phase concentrations inner droplets coalesce with each other. The so formed bigger inner droplets seem to increase the overall release rate. Copyright © 2013 Elsevier Inc. All rights reserved.

Numerical analysis of the effect of side holes of a double J stent on flow rate and pattern.

PubMed

Kim, Kyung-Wuk; Choi, Young Ho; Lee, Seung Bae; Baba, Yasutaka; Kim, Hyoung-Ho; Suh, Sang-Ho

2015-01-01

A double J stent has been used widely these days for patients with a ureteral stenosis or with renal stones and lithotripsy. The stent has multiple side holes in the shaft, which supply detours for urine flow. Even though medical companies produce various forms of double J stents that have different numbers and positions of side holes in the stent, the function of side holes in fluid dynamics has not been studied well. Here, the flow rate and pattern around the side holes of a double J stent were evaluated in curved models of a stented ureter based on the human anatomy and straight models for comparison. The total flow rate was higher in the stent with a greater number of side holes. The inflow and outflow to the stent through the side holes in the curved ureter was more active than in the straight ureter, which means the flow through side holes exists even in the ureter without ureteral stenosis or occlusion and even in the straight ureter. When the diameter of the ureter changed, the in-stent flow rate in the ureter did not change and the extraluminal flow rate was higher in the ureter with a greater diameter.

Millimeter-wave optical double resonance schemes for rapid assignment of perturbed spectra, with applications to the C{sup ~} {sup 1}B{sub 2} state of SO{sub 2}

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

Park, G. Barratt, E-mail: barratt@mit.edu, E-mail: barratt.park@gmail.com; Womack, Caroline C.; Jiang, Jun

2015-04-14

Millimeter-wave detected, millimeter-wave optical double resonance (mmODR) spectroscopy is a powerful tool for the analysis of dense, complicated regions in the optical spectra of small molecules. The availability of cavity-free microwave and millimeter wave spectrometers with frequency-agile generation and detection of radiation (required for chirped-pulse Fourier-transform spectroscopy) opens up new schemes for double resonance experiments. We demonstrate a multiplexed population labeling scheme for rapid acquisition of double resonance spectra, probing multiple rotational transitions simultaneously. We also demonstrate a millimeter-wave implementation of the coherence-converted population transfer scheme for background-free mmODR, which provides a ∼10-fold sensitivity improvement over the population labeling scheme.more » We analyze perturbations in the C{sup ~} state of SO{sub 2}, and we rotationally assign a b{sub 2} vibrational level at 45 328 cm{sup −1} that borrows intensity via a c-axis Coriolis interaction. We also demonstrate the effectiveness of our multiplexed mmODR scheme for rapid acquisition and assignment of three predissociated vibrational levels of the C{sup ~} state of SO{sub 2} between 46 800 and 47 650 cm{sup −1}.« less

Double Star Research: A Student-Centered Community of Practice

NASA Astrophysics Data System (ADS)

Johnson, Jolyon

2016-06-01

Project and team-based pedagogies are increasingly augmenting lecture-style science classrooms. Occasionally, university professors will invite students to tangentially partcipate in their research. Since 2006, Dr. Russ Genet has led an astronomy research seminar for community college and high school students that allows participants to work closely with a melange of professional and advanced amatuer researchers. The vast majority of topics have centered on measuring the position angles and searations of double stars which can be readily published in the Journal of Double Star Observations. In the intervening years, a collaborative community of practice (Wenger, 1998) formed with the students as lead researchers on their projects with the guidance of experienced astronomers and educators. The students who join the research seminar are often well prepared for further STEM education in college and career. Today, the research seminar involves multile schools in multiple states with a volunteer educator acting as an assistant instructor at each location. These assistant instructors interface with remote observatories, ensure progress is made, and recruit students. The key deliverables from each student team include a published research paper and a public presentation online or in-person. Citing a published paper on scholarship and college applications gives students' educational carreers a boost. Recently the Journal of Double Star Observations published its first special issue of exlusively student-centered research.

The nature of pulsar radio emission

NASA Astrophysics Data System (ADS)

Dyks, J.; Rudak, B.; Demorest, P.

2010-01-01

High-quality averaged radio profiles of some pulsars exhibit double, highly symmetric features both in emission and in absorption. It is shown that both types of feature are produced by a split fan beam of extraordinary-mode curvature radiation that is emitted/absorbed by radially extended streams of magnetospheric plasma. With no emissivity in the plane of the stream, such a beam produces bifurcated emission components (BFCs) when our line of sight passes through the plane. An example of a double component created in this way is present in the averaged profile of the 5-ms pulsar J1012+5307. We show that the component can indeed be very well fitted by the textbook formula for the non-coherent beam of curvature radiation in the polarization state that is orthogonal to the plane of electron trajectory. The observed width of the BFC decreases with increasing frequency at a rate that confirms the curvature origin. Likewise, the double absorption features (double notches) are produced by the same beam of the extraordinary-mode curvature radiation, when it is eclipsed by thin plasma streams. The intrinsic property of curvature radiation to create bifurcated fan beams explains the double features in terms of a very natural geometry and implies the curvature origin of pulsar radio emission. Similarly, the `double conal' profiles of class D result from a cut through a wider stream with finite extent in magnetic azimuth. Therefore, their width reacts very slowly to changes of viewing geometry resulting from geodetic precession. The stream-cut interpretation implies a highly non-orthodox origin of both the famous S-swing of polarization angle and the low-frequency pulse broadening in D profiles. The azimuthal structure of polarization modes in the curvature radiation beam provides an explanation for the polarized `multiple imaging' and the edge depolarization of pulsar profiles.

Analyzing Double Delays at Newark Liberty International Airport

NASA Technical Reports Server (NTRS)

Evans, Antony D.; Lee, Paul

2016-01-01

When weather or congestion impacts the National Airspace System, multiple different Traffic Management Initiatives can be implemented, sometimes with unintended consequences. One particular inefficiency that is commonly identified is in the interaction between Ground Delay Programs (GDPs) and time based metering of internal departures, or TMA scheduling. Internal departures under TMA scheduling can take large GDP delays, followed by large TMA scheduling delays, because they cannot be easily fitted into the overhead stream. In this paper we examine the causes of these double delays through an analysis of arrival operations at Newark Liberty International Airport (EWR) from June to August 2010. Depending on how the double delay is defined between 0.3 percent and 0.8 percent of arrivals at EWR experienced double delays in this period. However, this represents between 21 percent and 62 percent of all internal departures in GDP and TMA scheduling. A deep dive into the data reveals that two causes of high internal departure scheduling delays are upstream flights making up time between their estimated departure clearance times (EDCTs) and entry into time based metering, which undermines the sequencing and spacing underlying the flight EDCTs, and high demand on TMA, when TMA airborne metering delays are high. Data mining methods (currently) including logistic regression, support vector machines and K-nearest neighbors are used to predict the occurrence of double delays and high internal departure scheduling delays with accuracies up to 0.68. So far, key indicators of double delay and high internal departure scheduling delay are TMA virtual runway queue size, and the degree to which estimated runway demand based on TMA estimated times of arrival has changed relative to the estimated runway demand based on EDCTs. However, more analysis is needed to confirm this.

Double cusp encounter by Cluster: double cusp or motion of the cusp?

NASA Astrophysics Data System (ADS)

Escoubet, C. P.; Berchem, J.; Trattner, K. J.; Pitout, F.; Richard, R. L.; Taylor, M. G.; Soucek, J.; Grison, B.; Laakso, H. E.; Masson, A.; Dunlop, M. W.; Dandouras, I. S.; Reme, H.; Fazakerley, A. N.; Daly, P. W.

2012-12-01

Modeling plasma entry in the polar cusp has been successful in reproducing ion dispersions observed in the cusp at low and mid-altitudes. The use of a realistic convection pattern allowed Wing et al. [2001] to model double cusp signatures that were observed by the DMSP spacecraft when the Interplanetary Magnetic Field (IMF) is southward but has a dominant By component (|IMF-By|>|IMF-Bz|). Under these conditions, reconnection between the IMF and the geomagnetic field is predicted to occur both at high latitudes and around the equatorial plane (or subsolar region). This multiple reconnection topology subsequently produces two different injections of plasma into the cusp, hence the observation of the so-called double cusp. However, the two cusps can be very close to each other and a detailed analysis of the dispersion of the precipitating ions is very often required to clearly identify them. We will present a cusp crossing where two cusps are observed, separated by 1° ILAT. Cluster 1 and 2 observed these two cusps within a few minute interval and about 10 and 50 min later, respectively, Cluster 4 and 3 observed a single cusp only. A peculiarity of this event was the fact that the second cusp seen on C1 and C2 was observed at the same time as the first cusp on C4. This would tend to suggest that the two dispersions are spatial features similar to the double cusp. However more detailed analysis of the characteristics of the cusps (ion dispersion, boundaries) and the IMF abrupt changes clearly showed that the double cusp was in fact a single cusp that had moved toward dawn and then back toward dusk following the changes in the IMF direction.

Pulsed dye laser double-pass treatment of patients with resistant capillary malformations.

PubMed

Rajaratnam, Ratna; Laughlin, Sharyn A; Dudley, Denis

2011-07-01

The pulsed dye laser is an effective and established treatment for port-wine stains and has become the generally accepted standard of care. However, in many cases, complete clearance cannot be achieved as a significant proportion of lesions become resistant to treatment. Multiple passes or pulse-stacking techniques have been used to improve the extent and rate of fading, but concerns over increased adverse effects have limited this clinical approach. In this work, a double-pass technique with the pulsed dye laser has been described, which may allow for increased depth of vascular injury, greater efficacy, and an acceptable risk profile. Our aim was to determine the efficacy and the rate of side-effects for a double-pass protocol with a pulsed dye laser (PDL) to treat patients previously treated with PDL and/or other laser modalities. A retrospective chart review was conducted of 26 patients treated with a minimum of three double-pass treatments alone, or in combination, with single pass conventional PDL. Almost half of the patients (n = 12) showed either a moderate or significant improvement in fading compared to pre-treatment photographs with the double-pass technique. In a further 12 patients, there was a mild improvement. In two patients, there was no change. Sixteen patients developed mild side-effects: blisters (n = 5), dry scabs (n = 11) and transient hyperpigmentation (n = 4). This preliminary experience suggests that a double-pass technique at defined intervals between the first and second treatment with PDL can further lighten some port-wine stains, which are resistant to conventional single-pass treatments. This technique may be a useful addition to the laser treatment of PWS and deserves further scrutiny with randomized prospective studies and histological analysis to confirm the increased depth of vascular injury.

Double immunohistochemical staining with MUC4/p53 is useful in the distinction of pancreatic adenocarcinoma from chronic pancreatitis: a tissue microarray-based study.

PubMed

Bhardwaj, Atul; Marsh, William L; Nash, Jason W; Barbacioru, Catalin C; Jones, Susie; Frankel, Wendy L

2007-04-01

Immunohistochemical stains have been used for the distinction of pancreatic adenocarcinoma from chronic pancreatitis. To determine if a double stain for MUC/p53 improved specificity and sensitivity for distinction of pancreatic adenocarcinoma from chronic pancreatitis by comparing maspin, mucin 4 (MUC4), p53, Smad4, and the double stain MUC4/p53. Seventy-four pancreatic adenocarcinomas and 19 chronic pancreatitis cases were retrieved from archival files. Tissue cores were arrayed to create a tissue microarray of 2-mm cores. Sections were stained with antibodies against maspin, MUC4, p53, and Smad4. Additionally, a 2-color, double stain for MUC4 and p53 was developed and evaluated. Five percent or greater staining in either of the cores was considered positive. Intensity (0, 1, 2) and extent (%) of tumor cells staining was also determined. The sensitivity for distinction of pancreatic adenocarcinoma from chronic pancreatitis with maspin, MUC4, p53, and Smad4 was 90%, 77%, 60%, and 63%, respectively; the specificity was 67%, 78%, 88%, and 88%, respectively. When MUC4 and p53 were combined in a double stain, and positive staining for either considered a positive result, the sensitivity increased to 96% but specificity was 73%. When immunoreactivity for both antibodies was necessary for a positive result, sensitivity fell to 39% but specificity was 100%. No correlation was found between intensity or extent of staining with any of the individual stains and tumor differentiation. The double immunohistochemical stain for MUC4/p53 can be a useful diagnostic tool in conjunction with the hematoxylin-eosin-stained section for pancreatic adenocarcinoma, particularly when limited tumor is available for multiple stains.

Prolongation structures of nonlinear evolution equations. II

NASA Technical Reports Server (NTRS)

Estabrook, F. B.; Wahlquist, H. D.

1976-01-01

The prolongation structure of a closed ideal of exterior differential forms is further discussed, and its use illustrated by application to an ideal (in six dimensions) representing the cubically nonlinear Schroedinger equation. The prolongation structure in this case is explicitly given, and recurrence relations derived which support the conjecture that the structure is open - i.e., does not terminate as a set of structure relations of a finite-dimensional Lie group. We introduce the use of multiple pseudopotentials to generate multiple Baecklund transformation, and derive the double Baecklund transformation. This symmetric transformation concisely expresses the (usually conjectured) theorem of permutability, which must consequently apply to all solutions irrespective of asymptotic constraints.

Multiple core-hole formation by free-electron laser radiation in molecular nitrogen

NASA Astrophysics Data System (ADS)

Banks, H. I. B.; Little, D. A.; Emmanouilidou, A.

2018-05-01

We investigate the formation of multiple-core-hole states of molecular nitrogen interacting with a free-electron laser pulse. In previous work, we obtained bound and continuum molecular orbitals in the single-center expansion scheme and used these orbitals to calculate photo-ionization and auger decay rates. We extend our formulation to track the proportion of the population that accesses single-site versus two-site double-core-hole (TSDCH) states, before the formation of the final atomic ions. We investigate the pulse parameters that favor the formation of the single-site and TSDCH as well as triple-core-hole states for 525 and 1100 eV photons.

An elastic strip with multiple cracks and applications to tapered specimens

NASA Technical Reports Server (NTRS)

Liu, X.-H.; Erdogan, F.

1985-01-01

In this paper an infinite elastic strip containing arbitrarily oriented cracks and subjected to uniform tension and a pair of concentrated forces is formulated in terms of a system of singular integral equations. Even though the technique is sufficiently general to solve new multiple crack problem, with the objective of applying the results to tapered specimens, only a certain symmetric crack geometry and loading conditions are considered. The stress intensity factors are calculated for edge cracks in the strip under uniform tension and for a 'compact' and a 'slender' tapered specimen (the latter simulating the double cantilever beam) under concentrated forces or crack surface wedge forces.

Disentangling formation of multiple-core holes in aminophenol molecules exposed to bright X-FEL radiation

NASA Astrophysics Data System (ADS)

Zhaunerchyk, V.; Kamińska, M.; Mucke, M.; Squibb, R. J.; Eland, J. H. D.; Piancastelli, M. N.; Frasinski, L. J.; Grilj, J.; Koch, M.; McFarland, B. K.; Sistrunk, E.; Gühr, M.; Coffee, R. N.; Bostedt, C.; Bozek, J. D.; Salén, P.; Meulen, P. v. d.; Linusson, P.; Thomas, R. D.; Larsson, M.; Foucar, L.; Ullrich, J.; Motomura, K.; Mondal, S.; Ueda, K.; Richter, R.; Prince, K. C.; Takahashi, O.; Osipov, T.; Fang, L.; Murphy, B. F.; Berrah, N.; Feifel, R.

2015-12-01

Competing multi-photon ionization processes, some leading to the formation of double core hole states, have been examined in 4-aminophenol. The experiments used the linac coherent light source (LCLS) x-ray free electron laser, in combination with a time-of-flight magnetic bottle electron spectrometer and the correlation analysis method of covariance mapping. The results imply that 4-aminophenol molecules exposed to the focused x-ray pulses of the LCLS sequentially absorb more than two x-ray photons, resulting in the formation of multiple core holes as well as in the sequential removal of photoelectrons and Auger electrons (so-called PAPA sequences).

A polarization-division multiplexing SSB-OFDM system with beat interference cancellation receivers

NASA Astrophysics Data System (ADS)

Yang, Peiling; Ma, Jianxin; Zhang, Junyi

2018-06-01

In this paper, we have proposed a polarization-division multiplexing (PDM) single-sideband optical orthogonal frequency division multiplexing (SSB-OOFDM) scheme with signal-signal beat interference cancellation receivers with balanced detection (ICRBD). This system can double channel capacity and improve spectrum efficiency (SE) with the reduced guard band (GB) due to the PDM. Multiple input multiple output (MIMO) technique is used to solve polarization mode dispersion (PMD) associated with channel estimation and equalization. By simulation, we demonstrate the efficacy of the proposed technique for a 2 ×40 Gbit/s 16-QAM SSB-PDM-OOFDM system according to the error vector magnitude (EVM) and the constellation diagrams.

Disentangling formation of multiple-core holes in aminophenol molecules exposed to bright X-FEL radiation

DOE PAGES

Zhaunerchyk, V.; Kaminska, M.; Mucke, M.; ...

2015-10-28

Competing multi-photon ionization processes, some leading to the formation of double core hole states, have been examined in 4-aminophenol. The experiments used the linac coherent light source (LCLS) x-ray free electron laser, in combination with a time-of-flight magnetic bottle electron spectrometer and the correlation analysis method of covariance mapping. Furthermore, the results imply that 4-aminophenol molecules exposed to the focused x-ray pulses of the LCLS sequentially absorb more than two x-ray photons, resulting in the formation of multiple core holes as well as in the sequential removal of photoelectrons and Auger electrons (so-called PAPA sequences).

Relationships between body composition, body dimensions, and peak speed in cross-country sprint skiing.

PubMed

Stoggl, Thomas; Enqvist, Jonas; Muller, Erich; Holmberg, Hans-Christer

2010-01-01

In modern sprint cross-country skiing, strength and maximal speed are major determinants of performance. The aims of this study were to ascertain the anthropometric characteristics of world-class sprint skiers and to evaluate whether a specific body composition and/or body dimension characterizes a successful sprint skier. Our hypothesis was that body height and lean body mass are related to peak speed in double poling and diagonal stride. Fourteen male national and international elite skiers performed two peak speed tests in double poling and diagonal stride roller skiing on a treadmill and were analysed using dual-energy X-ray absorptiometry to determine body composition and body dimensions. Relative pole length was positively correlated with both techniques (double poling: r = 0.77, P < 0.01; diagonal stride: r = 0.60, P < 0.05) and was the only variable that was part of the multiple regression model for both double poling and diagonal stride peak speed. Body height was not correlated with any technique, whereas lean trunk mass (r = 0.75, P < 0.01), body mass index (r = 0.66, P < 0.01), total lean mass (r = 0.69, P < 0.01), and body mass (r = 0.57, P < 0.05) were positively related to double poling peak speed. Total lean mass (absolute: r = 0.58, P < 0.05; relative: r = 0.76, P < 0.001) and relative lean mass of the trunk, arms (both r = 0.72, P < 0.01), and legs (r = 0.54, P < 0.05) were positively related to diagonal stride peak speed. In conclusion, skiers should aim to achieve a body composition with a high percentage of lean mass and low fat mass. A focus on trunk mass through increased muscle mass appears to be important, especially for double poling. The use of longer poles (percent body height) seems to be advantageous for both double poling and diagonal stride peak speed, whereas body dimensions do not appear to be a predictive factor.

One-pot synthesis of carbon supported calcined-Mg/Al layered double hydroxides for antibiotic removal by slow pyrolysis of biomass waste

PubMed Central

Tan, Xiaofei; Liu, Shaobo; Liu, Yunguo; Gu, Yanling; Zeng, Guangming; Cai, Xiaoxi; Yan, ZhiLi; Yang, Chunping; Hu, Xinjiang; Chen, Bo

2016-01-01

A biochar supported calcined-Mg/Al layered double hydroxides composite (CLDHs/BC) was synthesized by a one-pot slow pyrolysis of LDHs preloaded bagasse biomass. Multiple characterizations of the product illustrated that the calcined-Mg/Al layered double hydroxides (CLDHs) were successfully coated onto the biochar in slow pyrolysis of pre-treated biomass. The as-synthesized CLDHs/BC could efficiently remove antibiotic tetracycline from aqueous solutions. The coating of CLDHs significantly increased the adsorption ability of biochar, and CLDHs/BC exhibited more than 2 times higher adsorption capacity than that of the pristine biochar (BC) in the tested pH range. The maximum adsorption capacity of CLDHs/BC for tetracycline was 1118.12 mg/g at 318 K. The experimental results suggested that the interaction with LDHs on biochar played a dominant role in tetracycline adsorption, accompanied with π–π interaction and hydrogen bond. This study provides a feasible and simple approach for the preparation of high-performance material for antibiotics contaminated wastewater treatment in a cost-effective way. PMID:28000759

Accessing the biocompatibility of layered double hydroxide by intramuscular implantation: histological and microcirculation evaluation

PubMed Central

Cunha, Vanessa Roberta Rodrigues; de Souza, Rodrigo Barbosa; da Fonseca Martins, Ana Maria Cristina Rebello Pinto; Koh, Ivan Hong Jun; Constantino, Vera Regina Leopoldo

2016-01-01

Biocompatibility of layered double hydroxides (LDHs), also known as hydrotalcite-like materials or double metal hydroxides, was investigated by in vivo assays via intramuscular tablets implantation in rat abdominal wall. The tablets were composed by chloride ions intercalated into LDH of magnesium/aluminum (Mg2Al-Cl) and zinc/aluminum (Zn2Al-Cl). The antigenicity and tissue integration capacity of LDHs were assessed histologically after 7 and 28 days post-implantation. No fibrous capsule nearby the LDH was noticed for both materials as well any sign of inflammatory reactions. Sidestream Dark Field imaging, used to monitor in real time the microcirculation in tissues, revealed overall integrity of the microcirculatory network neighboring the tablets, with no blood flow obstruction, bleeding and/or increasing of leukocyte endothelial adhesion. After 28 days Mg2Al-Cl promoted multiple collagen invaginations (mostly collagen type-I) among its fragments while Zn2Al-Cl induced predominantly collagen type–III. This work supports previous results in the literature about LDHs compatibility with living matter, endorsing them as functional materials for biomedical applications. PMID:27480483

Urinary Infections in Patients with Catheters in the Upper Urinary Tract: Microbiological Study.

PubMed

Lara-Isla, Alba; Medina-Polo, José; Alonso-Isa, Manuel; Benítez-Sala, Raúl; Sopeña-Sutil, Raquel; Justo-Quintas, Juan; Gil-Moradillo, Javier; González-Padilla, Daniel A; García-Rojo, Esther; Passas-Martínez, Juan Bautista; Tejido-Sánchez, Ángel

2017-01-01

Infections related to catheters in the upper urinary tract (CUUT) are associated with specific characteristics. A prospective observational study was carried out from 2012 to 2015 to evaluate infections in patients with CUUT. A total of 209 infections were included (99 with double-J, 81 with nephrostomy, and 29 with internal/external nephroureteral stents). Among nephrostomy tube carriers, the most frequently isolated microorganisms were Pseudomonas and Enterococcus. In those with an internal/external nephroureteral stent, Klebsiella was the most common, and 57.1% were extended-spectrum beta-lactamase-producing Klebsiella. In double-J carriers, Escherichia coli and Enterococcus were the most common microorganisms. Multiple-drug resistance (MDR) microorganisms were isolated in 28.6, 47.1, and 58.3% of patients with double-J, nephrostomy, and internal-external nephroureteral stents. A percutaneous CUUT (p = 0.005) and immunosuppression (p = 0.034) were risk factors for MDR microorganisms. Non-E. coli bacteria are commonly isolated in patients with CUUT. MDR microorganisms are frequent, mainly in percutaneous approach or immunosuppression. © 2017 S. Karger AG, Basel.

Evaluation of double photon coincidence Compton imaging method with GEANT4 simulation

NASA Astrophysics Data System (ADS)

Yoshihara, Yuri; Shimazoe, Kenji; Mizumachi, Yuki; Takahashi, Hiroyuki

2017-11-01

Compton imaging has been used for various applications including astronomical observations, radioactive waste management, and biomedical imaging. The positions of radioisotopes are determined in the intersections of multiple cone traces through a large number of events, which reduces signal to noise ratio (SNR) of the images. We have developed an advanced Compton imaging method to localize radioisotopes with high SNR by using information of the interactions of Compton scattering caused by two gamma rays at the same time, as the double photon coincidence Compton imaging method. The targeted radioisotopes of this imaging method are specific nuclides that emit several gamma rays at the same time such as 60Co, 134Cs, and 111In, etc. Since their locations are determined in the intersections of two Compton cones, the most of cone traces would disappear in the three-dimensional space, which enhances the SNR and angular resolution. In this paper, the comparison of the double photon coincidence Compton imaging method and the single photon Compton imaging method was conducted by using GEANT4 Monte Carlo simulation.

Partial double-layered patella in a nondysplasic adolescent.

PubMed

García-Mata, Serafín; Hidalgo-Ovejero, Angel

2016-11-01

Double-layered patella (DLP) is a rare patella-formation abnormality reported in association with multiple epiphyseal dysplasia. DLP is one of the five types of bipartite patella, caused by a coronal septum that divides the patella into anterior and posterior segments. Although the double layer of bone has been reported as complete, it may also manifest as partial, as in our case. A 13-year-old male patient attended A&E after accidentally falling and sustaining a direct injury to his left knee, with pain in the anterior surface of the right patella. He was diagnosed with an incomplete vertical fracture of the left patella. An axial view radiography indicated an external partial DLP. No bone dysplasia was found. Computed tomographic scan and MRI showed partial DLP and bone marrow oedema because of the injury in the femoral condyle, but no fracture. The reason for highlighting this type of patella abnormality is to present the case of a patient without bone dysplasia, either partial or incomplete, that has not been reported previously. We also wish to emphasize the importance of not confusing it with a fracture in standard radiographies.

One-pot synthesis of carbon supported calcined-Mg/Al layered double hydroxides for antibiotic removal by slow pyrolysis of biomass waste

NASA Astrophysics Data System (ADS)

Tan, Xiaofei; Liu, Shaobo; Liu, Yunguo; Gu, Yanling; Zeng, Guangming; Cai, Xiaoxi; Yan, Zhili; Yang, Chunping; Hu, Xinjiang; Chen, Bo

2016-12-01

A biochar supported calcined-Mg/Al layered double hydroxides composite (CLDHs/BC) was synthesized by a one-pot slow pyrolysis of LDHs preloaded bagasse biomass. Multiple characterizations of the product illustrated that the calcined-Mg/Al layered double hydroxides (CLDHs) were successfully coated onto the biochar in slow pyrolysis of pre-treated biomass. The as-synthesized CLDHs/BC could efficiently remove antibiotic tetracycline from aqueous solutions. The coating of CLDHs significantly increased the adsorption ability of biochar, and CLDHs/BC exhibited more than 2 times higher adsorption capacity than that of the pristine biochar (BC) in the tested pH range. The maximum adsorption capacity of CLDHs/BC for tetracycline was 1118.12 mg/g at 318 K. The experimental results suggested that the interaction with LDHs on biochar played a dominant role in tetracycline adsorption, accompanied with π-π interaction and hydrogen bond. This study provides a feasible and simple approach for the preparation of high-performance material for antibiotics contaminated wastewater treatment in a cost-effective way.

Accessing the biocompatibility of layered double hydroxide by intramuscular implantation: histological and microcirculation evaluation.

PubMed

Cunha, Vanessa Roberta Rodrigues; de Souza, Rodrigo Barbosa; da Fonseca Martins, Ana Maria Cristina Rebello Pinto; Koh, Ivan Hong Jun; Constantino, Vera Regina Leopoldo

2016-08-02

Biocompatibility of layered double hydroxides (LDHs), also known as hydrotalcite-like materials or double metal hydroxides, was investigated by in vivo assays via intramuscular tablets implantation in rat abdominal wall. The tablets were composed by chloride ions intercalated into LDH of magnesium/aluminum (Mg2Al-Cl) and zinc/aluminum (Zn2Al-Cl). The antigenicity and tissue integration capacity of LDHs were assessed histologically after 7 and 28 days post-implantation. No fibrous capsule nearby the LDH was noticed for both materials as well any sign of inflammatory reactions. Sidestream Dark Field imaging, used to monitor in real time the microcirculation in tissues, revealed overall integrity of the microcirculatory network neighboring the tablets, with no blood flow obstruction, bleeding and/or increasing of leukocyte endothelial adhesion. After 28 days Mg2Al-Cl promoted multiple collagen invaginations (mostly collagen type-I) among its fragments while Zn2Al-Cl induced predominantly collagen type-III. This work supports previous results in the literature about LDHs compatibility with living matter, endorsing them as functional materials for biomedical applications.

Diagnostic study of multiple double layer formation in expanding RF plasma

NASA Astrophysics Data System (ADS)

Chakraborty, Shamik; Paul, Manash Kumar; Roy, Jitendra Nath; Nath, Aparna

2018-03-01

Intensely luminous double layers develop and then expand in size in a visibly glowing RF discharge produced using a plasma source consisting of a semi-transparent cylindrical mesh with a central electrode, in a linear plasma chamber. Although RF discharge is known to be independent of device geometry in the absence of magnetic field, the initiation of RF discharge using such a plasma source results in electron drift and further expansion of the plasma in the vessel. The dynamics of complex plasma structures are studied through electric probe diagnostics in the expanding RF plasma. The measurements made to study the parametric dependence of evolution of double layer structures are analyzed and presented here. The plasma parameter measurements suggest that the complex potential structures initially form with low potential difference between the layers and then gradually expand producing burst oscillations. The present study provides interesting information about the stability of plasma sheath and charge particle dynamics in it that are important to understand the underlying basic sheath physics along with applications in plasma acceleration and propulsion.

Absorption coefficient and relative refractive index change for a double δ-doped GaAs MIGFET-like structure: Electric and magnetic field effects

NASA Astrophysics Data System (ADS)

Martínez-Orozco, J. C.; Rodríguez-Magdaleno, K. A.; Suárez-López, J. R.; Duque, C. A.; Restrepo, R. L.

2016-04-01

In this work we present theoretical results for the electronic structure as well as for the absorption coefficient and relative refractive index change for an asymmetric double δ-doped like confining potential in the active region of a Multiple Independent Gate Field Effect Transistor (MIGFET) system. We model the potential profile as a double δ-doped like potential profile between two Schottky (parabolic) potential barriers that are just the main characteristics of the MIGFET configuration. We investigate the effect of external electromagnetic fields in this kind of quantum structures, in particular we applied a homogeneous constant electric field in the growth direction z as well as a homogeneous constant magnetic field in the x-direction. In general we conclude that by applying electromagnetic fields we can modulate the resonant peaks of the absorption coefficient as well as their energy position. Also with such probes it is possible to control the nodes and amplitude of the relative refractive index changes related to resonant intersubband optical transitions.

Interactions of double patterning technology with wafer processing, OPC and design flows

NASA Astrophysics Data System (ADS)

Lucas, Kevin; Cork, Chris; Miloslavsky, Alex; Luk-Pat, Gerry; Barnes, Levi; Hapli, John; Lewellen, John; Rollins, Greg; Wiaux, Vincent; Verhaegen, Staf

2008-03-01

Double patterning technology (DPT) is one of the main options for printing logic devices with half-pitch less than 45nm; and flash and DRAM memory devices with half-pitch less than 40nm. DPT methods decompose the original design intent into two individual masking layers which are each patterned using single exposures and existing 193nm lithography tools. The results of the individual patterning layers combine to re-create the design intent pattern on the wafer. In this paper we study interactions of DPT with lithography, masks synthesis and physical design flows. Double exposure and etch patterning steps create complexity for both process and design flows. DPT decomposition is a critical software step which will be performed in physical design and also in mask synthesis. Decomposition includes cutting (splitting) of original design intent polygons into multiple polygons where required; and coloring of the resulting polygons. We evaluate the ability to meet key physical design goals such as: reduce circuit area; minimize rework; ensure DPT compliance; guarantee patterning robustness on individual layer targets; ensure symmetric wafer results; and create uniform wafer density for the individual patterning layers.

Transition metal atomic multiplets in the ligand K-edge x-ray absorption spectra and multiple oxidation states in the L2,3 emission of strongly correlated compounds

NASA Astrophysics Data System (ADS)

Jiménez-Mier, J.; Olalde-Velasco, P.; Yang, W.-L.; Denlinger, J.

2014-07-01

We present results that show that atomic multiplet ligand field calculations are in very good agreement with experimental x-ray absorption spectra at the L2,3 edge of transition metal (TM) di-fluorides (MF2, MCrCu). For chromium more than one TM oxidation state is needed to achieve such an agreement. We also show that signature of the TM atomic multiplet can be found at the pre-edge of the fluorine K-edge x-ray absorption spectra. TM atomic multiplet ligand field calculations with a structureless core hole show good agreement with the observed pre-edges in the experimental fluorine absorption spectra. Preliminary results for the comparison between calculated and experimental resonant x-ray emission spectra for nominal CrF2 with more than one oxidation state indicate the presence of three chromium oxidation states in the bulk.

Error control for reliable digital data transmission and storage systems

NASA Technical Reports Server (NTRS)

Costello, D. J., Jr.; Deng, R. H.

1985-01-01

A problem in designing semiconductor memories is to provide some measure of error control without requiring excessive coding overhead or decoding time. In LSI and VLSI technology, memories are often organized on a multiple bit (or byte) per chip basis. For example, some 256K-bit DRAM's are organized in 32Kx8 bit-bytes. Byte oriented codes such as Reed Solomon (RS) codes can provide efficient low overhead error control for such memories. However, the standard iterative algorithm for decoding RS codes is too slow for these applications. In this paper we present some special decoding techniques for extended single-and-double-error-correcting RS codes which are capable of high speed operation. These techniques are designed to find the error locations and the error values directly from the syndrome without having to use the iterative alorithm to find the error locator polynomial. Two codes are considered: (1) a d sub min = 4 single-byte-error-correcting (SBEC), double-byte-error-detecting (DBED) RS code; and (2) a d sub min = 6 double-byte-error-correcting (DBEC), triple-byte-error-detecting (TBED) RS code.

Visualized measurement of the acoustic levitation field based on digital holography with phase multiplication

NASA Astrophysics Data System (ADS)

Zheng, Puchao; Li, Enpu; Zhao, Jianlin; Di, Jianglei; Zhou, Wangmin; Wang, Hao; Zhang, Ruifeng

2009-11-01

By using digital holographic interferometory with phase multiplication, the visualized measurement of the acoustic levitation field (ALF) with single axis is carried out. The digital holograms of the ALF under different conditions are recorded by use of CCD. The corresponding digital holographic interferograms reflecting the sound pressure distribution and the interference phase distribution are obtained by numerical reconstruction and phase subtraction, which are consistent with the theoretical results. It indicates that the proposed digital holographic interferometory with phase multiplication can successfully double the fringe number of the interference phase patterns of the ALF and improve the measurement precision. Compared with the conventional optical holographic interferometory, digital holographic interferometory has the merits of quasi real-time, more exactitude and convenient operation, and it provides an effective way for studying the sound pressure distribution of the ALF.

Tanovea® for the treatment of lymphoma in dogs.

PubMed

De Clercq, Erik

2018-05-17

Tanovea® (first named GS-9219, then VDC-1101, generic name: rabacfosadine) is a pro-prodrug or "double" prodrug of PMEG [9-(2-phosphonylmethoxyethyl)guanine], which has been conditionally approved by the US FDA (Food and Drug Administration) for the treatment of lymphoma in dogs. Tanovea has been demonstrated to be effective against non-Hodgkin's lymphoma (NHL) in dogs, as well as canine cutaneous T-cell lymphoma, spontaneous canine multiple myeloma, naïve canine multicentric lymphoma and relapsed canine B-cell lymphoma. As a double prodrug of PMEG, GS-9219 is first converted intracellularly by hydrolysis to cPr-PMEDAP, then deaminated to PMEG, which is then phosphorylated twice to its active metabolite PMEGpp, acting at the level of the cellular DNA polymerases. Copyright © 2018 Elsevier Inc. All rights reserved.

Strange and non-strange particle production in antiproton-nucleus collisions in the UrQMD model

NASA Astrophysics Data System (ADS)

Limphirat, Ayut; Kobdaj, Chinorat; Bleicher, Marcus; Yan, Yupeng; Stöcker, Horst

2009-06-01

The capabilities of the ultra-relativistic quantum molecular dynamics (UrQMD) model in describing antiproton-nucleus collisions are presented. The model provides a good description of the experimental data on multiplicities, transverse momentum distributions and rapidity distributions in antiproton-nucleus collisions. Special emphasis is put on the comparison of strange particles in reactions with nuclear targets ranging from 7Li, 12C, 32S, 64Cu to 131Xe because of the important role of strangeness for the exploration of hypernuclei at PANDA-FAIR. The productions of the double strange baryons Ξ- and \\bar{\\Xi}^+ , which may be used to produce double Λ hypernuclei, are predicted in this work for the reactions \\skew2\\bar{p} + 24Mg, 64Cu and 197Au.

Scaling Laws of the Two-Electron Sum-Energy Spectrum in Strong-Field Double Ionization.

PubMed

Ye, Difa; Li, Min; Fu, Libin; Liu, Jie; Gong, Qihuang; Liu, Yunquan; Ullrich, J

2015-09-18

The sum-energy spectrum of two correlated electrons emitted in nonsequential strong-field double ionization (SFDI) of Ar was studied for intensities of 0.3 to 2×10^{14} W/cm^{2}. We find the mean sum energy, the maximum of the distributions as well as the high-energy tail of the scaled (to the ponderomotive energy) spectra increase with decreasing intensity below the recollision threshold (BRT). At higher intensities the spectra collapse into a single distribution. This behavior can be well explained within a semiclassical model providing clear evidence of the importance of multiple recollisions in the BRT regime. Here, ultrafast thermalization between both electrons is found occurring within three optical cycles only and leaving its clear footprint in the sum-energy spectra.

[Survival of patients with primary central nervous system diffuse large B-cell lymphoma: impact of gene aberrations and protein overexpression of bcl-2 and C-MYC, and selection of chemotherapy regimens].

PubMed

Yin, W J; Zhu, X; Yang, H Y; Sun, W Y; Wu, M J

2018-01-08

Objective: To investigate the impact of clinicopathological features, gene rearrangements and protein expression of bcl-6, bcl-2, C-MYC and chemotherapy regime on the prognosis of patients with primary central nervous system diffuse large B-cell lymphoma (PCNS-DLBCL). Methods: Thirty-three cases of PCNS-DLBCL diagnosed from January 2006 to December 2016 at Zhejiang Cancer Hospital were collected. The expression of CD10, bcl-6, bcl-2, MUM1 and MYC were detected by immunohistochemical staining (IHC). The presence of EB virus was detected by in situ hybridization(EBER). Copy number variation (ICN) and translocation status of bcl-6, bcl-2 and C-MYC genes were detected by fluorescence in situ hybridization (FISH). The relationship between the above indexes and the prognosis was analyzed by univariate, bivariate survival analysis and multiple Cox hazard regression analysis. Results: The study included 33 patients of PCNS-DLBCL, without evidence of primary or secondary immunodeficient disease. Male to female ratio was 1.36∶1.00, and the average age was 56 years. Twenty cases had single lesion while 13 had multiple lesions. Deep brain involvement was seen in 12 cases. All patients underwent partial or total tumor resection. Five patients received whole brain post-surgery radiotherapy, nine patients received high-dose methotrexate (HD-MTX) based chemotherapy, and 12 patients received whole-brain radiotherapy combined with HD-MTX based chemotherapy. Severn patients received no further treatment and rituximab was used in 8 patients. According to the Hans model, 27 cases were classified as non-GCB subtypes (81.8%). Bcl-2 was positive in 25 cases (75.8%, 25/33) and highly expressed in 8 (24.2%). MYC was positive in 12 cases (36.4%) and double expression of bcl-2 and MYC was seen in 6 cases. EBER positive rate was 10.0%(3/30), all of which had multiple lesions. Two bcl-6 gene translocations and 3 amplifications were found in 28 patients. Two translocations, 3 ICN or with both bcl-2 gene translocation and ICN were found in 30 patients. Four ICNs of C-MYC gene were found in 28 patients. Elevated protein in cerebrospinal fluid (CSF) was found in 13 patients. LDH increased in 10 cases. Follow-up period was 2-90 months with the average survival time of (23.0±3.7) months and two-year survival rate of 39.0%. Univariate survival analysis showed that overexpression of bcl-2 protein (≥70%) and MYC protein (≥40%), bcl-2 gene abnormality (including copy number increase and translocation), C-MYC gene copy number increased were adverse factors for survival. C-MYC/ bcl-2 gene double hit was seen in 2 cases. Bivariate survival analysis found that of bcl-2/MYC protein double expression and bcl-2 and C-MYC genes double aberration were significantly associated with adverse outcomes. Cox multivariate risk regression analysis found that gender, cerebrospinal fluid protein increasing, and ICN of C-MYC gene were independent poor prognostic factors. DH-MTX based comprehensive chemotherapy was associated with better prognosis. Conclusions: Double hit at genomic level (copy number variations and gene rearrangements) and double protein expression of bcl-2 and C-MYC in PCNS-DLBCL are significantly associated with an adverse outcome. DH-MTX based comprehensive treatment may prolong the patient survival.

Air Force Research Laboratory High Power Electric Propulsion Technology Development

DTIC Science & Technology

2009-10-27

Plasmas in a Coaxial Double Theta Pinch, “ Doctoral Dissertation, Department of Aerospace Engineering, University of Michigan, Ann Arbor, MI, 2008. [6...surpasses the level of DARPA FAST goals. Several evolving propulsion concepts may enable a viable high-power plasma propulsion device suitable for...of PEPL) 5 performance operation with multiple cathodes or in a single- shared cathode configuration [4]. However, the local plasma properties

Analysis of multiple time scales in a transistor amplifier.

PubMed

Armstead, Douglas N; Carroll, Thomas L

2005-03-01

It was shown previously in an experiment that when high frequency signals (on the order of 1 MHz) were injected into this low frequency amplifier, the nonlinearities of the pn junctions caused period doubling, chaos, and very low frequency oscillations (on the order of 1 Hz). In this paper we present theory and simulations to explain the existence of the low frequency oscillations.

47 CFR 73.756 - System specifications for double-sideband (DBS) modulated emissions in the HF broadcasting service.

Code of Federal Regulations, 2014 CFR

2014-10-01

.... Nominal carrier frequencies shall be integral multiples of 5 kHz. (2) Audio-frequency band. The upper limit of the audio-frequency band (at—3 dB) of the transmitter shall not exceed 4.5 kHz and the lower... processing. If audio-frequency signal processing is used, the dynamic range of the modulating signal shall be...

47 CFR 73.756 - System specifications for double-sideband (DBS) modulated emissions in the HF broadcasting service.

Code of Federal Regulations, 2012 CFR

2012-10-01

.... Nominal carrier frequencies shall be integral multiples of 5 kHz. (2) Audio-frequency band. The upper limit of the audio-frequency band (at—3 dB) of the transmitter shall not exceed 4.5 kHz and the lower... processing. If audio-frequency signal processing is used, the dynamic range of the modulating signal shall be...

47 CFR 73.756 - System specifications for double-sideband (DBS) modulated emissions in the HF broadcasting service.

Code of Federal Regulations, 2011 CFR

2011-10-01

.... Nominal carrier frequencies shall be integral multiples of 5 kHz. (2) Audio-frequency band. The upper limit of the audio-frequency band (at—3 dB) of the transmitter shall not exceed 4.5 kHz and the lower... processing. If audio-frequency signal processing is used, the dynamic range of the modulating signal shall be...

47 CFR 73.756 - System specifications for double-sideband (DBS) modulated emissions in the HF broadcasting service.

Code of Federal Regulations, 2013 CFR

2013-10-01

.... Nominal carrier frequencies shall be integral multiples of 5 kHz. (2) Audio-frequency band. The upper limit of the audio-frequency band (at—3 dB) of the transmitter shall not exceed 4.5 kHz and the lower... processing. If audio-frequency signal processing is used, the dynamic range of the modulating signal shall be...

An Application of Double-Loop Learning to Community College Remedial Education: A New Model of Integrated Supports for Ongoing Student Success

ERIC Educational Resources Information Center

Doren, Andrew T.

2013-01-01

Community colleges have multiple missions and one of them is to provide open access services to those seeking to further their education. Community colleges provide remedial courses in math, reading, and writing because many of their students do not meet entrance requirements in these core subjects. However, the usual developmental education track…

Lattice fermions

NASA Technical Reports Server (NTRS)

Wilczek, Frank

1987-01-01

A simple heuristic proof of the Nielsen-Ninomaya theorem is given. A method is proposed whereby the multiplication of fermion species on a lattice is reduced to the minimal doubling, in any dimension, with retention of appropriate chiral symmetries. Also, it is suggested that use of spatially thinned fermion fields is likely to be a useful and appropriate approximation in QCD - in any case, it is a self-checking one.

Competition between second harmonic generation and two-photon-induced luminescence in single, double and multiple ZnO nanorods.

PubMed

Dai, Jun; Zeng, Jian-Hua; Lan, Sheng; Wan, Xia; Tie, Shao-Long

2013-04-22

The nonlinear optical properties of single, double and multiple ZnO nanorods (NRs) were investigated by using a focused femtosecond (fs) laser beam. The excitation wavelength of the fs laser was intentionally chosen to be 754 nm at which the energy of two photons is slightly larger than that of the exciton ground state but smaller than the bandgap energy of ZnO. Second harmonic generation (SHG) or/and two-photon-induced luminescence (TPL) were observed and their dependences on excitation density were examined. For single ZnO NRs, only SHG was observed even at the highest excitation density we used in the experiments. The situation was changed when the joint point of two ZnO NRs perpendicular to each other was excited. In this case, TPL could be detected at low excitation densities and it increased rapidly with increasing excitation density. At the highest excitation density of ~15 MW/cm(2), the intensity of the TPL became comparable to that of the SHG. For an ensemble of ZnO NRs packed closely, a rapid increase of TPL with a slope of more than 7.0 and a gradual saturation of SHG with a slope of ~0.34 were found at high excitation densities. Consequently, the nonlinear response spectrum was eventually dominated by the TPL at high excitation densities and the SHG appeared to be very weak. We interpret this phenomenon by considering both the difference in electric field distribution and the effect of heat accumulation. It is suggested that the electric field enhancement in double and multiple NRs plays a crucial role in determining the nonlinear response of the NRs. In addition, the reduction in the bandgap energy induced by the heat accumulation effect also leads to the significant change in nonlinear response. This explanation is supported by the calculation of the electric field distribution using the discrete dipole approximation method and the simulation of temperature rise in different ZnO NRs based on the finite element method.

Management of multiple myeloma in older adults: Gaining ground with geriatric assessment.

PubMed

Wildes, Tanya M; Campagnaro, Erica

2017-01-01

Multiple myeloma increases in incidence with age. With the aging of the population, the number of cases of multiple myeloma diagnosed in older adults each year will nearly double in the next 20years. The novel therapeutic agents have significantly improved survival in older adults, but their outcomes remain poorer than in younger patients. Older adults may be more vulnerable to toxicity of therapy, resulting in decreased dose intensity and contributing to poorer outcomes. Data are beginning to emerge to aid in identifying which individuals are at greater risk for toxicity of therapy; comorbidities, functional limitations, and age over 80years are among the factors associated with greater risk. Geriatric assessment holds promise in the care of older adults with multiple myeloma, both to allow modification of treatment to prevent toxicity, and to identify vulnerabilities that may require intervention. Emerging treatments with low toxicity and attention to individualizing therapy based on geriatric assessment may aid in further improving outcomes in older adults with multiple myeloma. Copyright © 2016 Elsevier Inc. All rights reserved.

Assisting persons with multiple disabilities to move through simple occupational activities with automatic prompting.

PubMed

Lancioni, Giulio E; Singh, Nirbhay N; O'Reilly, Mark F; Sigafoos, Jeff; Oliva, Doretta; Campodonico, Francesca; Groeneweg, Jop

2008-01-01

The present study assessed the possibility of assisting four persons with multiple disabilities to move through and perform simple occupational activities arranged within a room with the help of automatic prompting. The study involved two multiple probe designs across participants. The first multiple probe concerned the two participants with blindness or minimal vision and deafness, who received air blowing as a prompt. The second multiple probe concerned the two participants with blindness and typical hearing who received a voice calling as a prompt. Initially, all participants had baseline sessions. Then intervention started with the first participant of each dyad. When their performance was consolidated, new baseline and intervention occurred with the second participant of each dyad. Finally, all four participants were exposed to a second intervention phase, in which the number of activities per session doubled (i.e., from 8 to 16). Data showed that all four participants: (a) learned to move across and perform the activities available with the help of automatic prompting and (b) remained highly successful through the second intervention phase when the sessions were extended. Implications of the findings are discussed.

Tudor staphylococcal nuclease is a structure-specific ribonuclease that degrades RNA at unstructured regions during microRNA decay.

PubMed

Li, Chia-Lung; Yang, Wei-Zen; Shi, Zhonghao; Yuan, Hanna S

2018-05-01

Tudor staphylococcal nuclease (TSN) is an evolutionarily conserved ribonuclease in eukaryotes that is composed of five staphylococcal nuclease-like domains (SN1-SN5) and a Tudor domain. TSN degrades hyper-edited double-stranded RNA, including primary miRNA precursors containing multiple I•U and U•I pairs, and mature miRNA during miRNA decay. However, how TSN binds and degrades its RNA substrates remains unclear. Here, we show that the C. elegans TSN (cTSN) is a monomeric Ca 2+ -dependent ribonuclease, cleaving RNA chains at the 5'-side of the phosphodiester linkage to produce degraded fragments with 5'-hydroxyl and 3'-phosphate ends. cTSN degrades single-stranded RNA and double-stranded RNA containing mismatched base pairs, but is not restricted to those containing multiple I•U and U•I pairs. cTSN has at least two catalytic active sites located in the SN1 and SN3 domains, since mutations of the putative Ca 2+ -binding residues in these two domains strongly impaired its ribonuclease activity. We further show by small-angle X-ray scattering that rice osTSN has a flexible two-lobed structure with open to closed conformations, indicating that TSN may change its conformation upon RNA binding. We conclude that TSN is a structure-specific ribonuclease targeting not only single-stranded RNA, but also unstructured regions of double-stranded RNA. This study provides the molecular basis for how TSN cooperates with RNA editing to eliminate duplex RNA in cell defense, and how TSN selects and degrades RNA during microRNA decay. © 2018 Li et al.; Published by Cold Spring Harbor Laboratory Press for the RNA Society.

Self-organized criticality: An interplay between stable and turbulent regimes of multiple anodic double layers in glow discharge plasma

NASA Astrophysics Data System (ADS)

Alex, Prince; Carreras, Benjamin Andres; Arumugam, Saravanan; Sinha, Suraj Kumar

2018-05-01

The role of self-organized criticality (SOC) in the transformation of multiple anodic double layers (MADLs) from the stable to turbulent regime has been investigated experimentally as the system approaches towards critical behavior. The experiment was performed in a modified glow discharge plasma setup, and the initial stable state of MADL comprising three concentric perceptible layers was produced when the drift velocity of electrons towards the anode exceeds the electron thermal velocity (νd ≥ 1.3νte). The macroscopic arrangement of both positive and negative charges in opposite layers of MADL is attributed to the self-organization scenario. Beyond νd ≥ 3νte, MADL begins to collapse and approaches critical and supercritical states through layer reduction which continue till the last remaining layer of the double layer is transformed into a highly unstable radiant anode glow. The avalanche resulting from the collapse of MADL leads to the rise of turbulence in the system. Long-range correlations, a key signature of SOC, have been explored in the turbulent floating potential fluctuations using the rescaled-range analysis technique. The result shows that the existence of the self-similarity regime with self-similarity parameter H varies between 0.55 and 0.91 for time lags longer than the decorrelation time. The power law tail in the rank function, slowly decaying tail of the autocorrelation function, and 1/f behavior of the power spectra of the fluctuations are consistent with the fact that SOC plays a conclusive role in the transformation of MADL from the stable to turbulent regime. Since the existence of SOC gives a measure of complexity in the system, the result provides the condition under which complexity arises in cold plasma.

Statistical methods for incomplete data: Some results on model misspecification.

PubMed

McIsaac, Michael; Cook, R J

2017-02-01

Inverse probability weighted estimating equations and multiple imputation are two of the most studied frameworks for dealing with incomplete data in clinical and epidemiological research. We examine the limiting behaviour of estimators arising from inverse probability weighted estimating equations, augmented inverse probability weighted estimating equations and multiple imputation when the requisite auxiliary models are misspecified. We compute limiting values for settings involving binary responses and covariates and illustrate the effects of model misspecification using simulations based on data from a breast cancer clinical trial. We demonstrate that, even when both auxiliary models are misspecified, the asymptotic biases of double-robust augmented inverse probability weighted estimators are often smaller than the asymptotic biases of estimators arising from complete-case analyses, inverse probability weighting or multiple imputation. We further demonstrate that use of inverse probability weighting or multiple imputation with slightly misspecified auxiliary models can actually result in greater asymptotic bias than the use of naïve, complete case analyses. These asymptotic results are shown to be consistent with empirical results from simulation studies.

Multiple Ions Resonant Heating and Acceleration by Alfven/cyclotron Fluctuations in the Solar Wind

NASA Astrophysics Data System (ADS)

Xie, H.; Ofman, L.

2003-12-01

We study the interaction between protons, and multiple minor ions (O5+, He++) and a given cyclotron resonant spectra in coronal hole plasma. One-dimensional hybrid simulations are performed in initially homogeneous, collisionless, magnetized plasma with waves propagating parallel to the background magnetic field. The self-consistent hybrid simulations are used to study how multiple minor species may affect the resonance interaction between a spectrum of waves and the solar wind protons. The results of the simulations provide a clear picture of wave-particle interaction under various coronal conditions, which can explain 1) how multiple minor ions affect the resonant heating and the temperature anisotropy of the solar wind protons by a given wave spectrum; 2) how energy is distributed and transferred among waves and different ion species; 3) the growth and damping of different beam microinstability modes, including both inward and outward waves; 4) the formation of proton double-peak distribution in the solar wind.

High-mobility group box 1 is an important mediator of microglial activation induced by cortical spreading depression.

PubMed

Takizawa, Tsubasa; Shibata, Mamoru; Kayama, Yohei; Shimizu, Toshihiko; Toriumi, Haruki; Ebine, Taeko; Unekawa, Miyuki; Koh, Anri; Yoshimura, Akihiko; Suzuki, Norihiro

2017-03-01

Single episodes of cortical spreading depression (CSD) are believed to cause typical migraine aura, whereas clusters of spreading depolarizations have been observed in cerebral ischemia and subarachnoid hemorrhage. We recently demonstrated that the release of high-mobility group box 1 (HMGB1) from cortical neurons after CSD in a rodent model is dependent on the number of CSD episodes, such that only multiple CSD episodes can induce significant HMGB1 release. Here, we report that only multiple CSD inductions caused microglial hypertrophy (activation) accompanied by a greater impact on the transcription activity of the HMGB1 receptor genes, TLR2 and TLR4, while the total number of cortical microglia was not affected. Both an HMGB1-neurtalizing antibody and the HMGB1 inhibitor glycyrrhizin abrogated multiple CSD-induced microglial hypertrophy. Moreover, multiple CSD inductions failed to induce microglial hypertrophy in TLR2/4 double knockout mice. These results strongly implicate the HMGB1-TLR2/4 axis in the activation of microglia following multiple CSD inductions. Increased expression of the lysosomal acid hydrolase cathepsin D was detected in activated microglia by immunostaining, suggesting that lysosomal phagocytic activity may be enhanced in multiple CSD-activated microglia.

Double product and end-organ damage in African and Caucasian men: the SABPA study.

PubMed

Schultz, A J; Schutte, A E; Schutte, R

2013-08-10

Increasing urbanisation in sub-Saharan African countries is causing a rapid increase in cardiovascular disease. Evidence suggests that Africans have higher blood pressures and a higher prevalence of hypertension-related cardiovascular morbidity and mortality, compared to Caucasians. We investigated double product (systolic blood pressure × heart rate), a substantial measure of cardiac workload, as a possible cardiovascular risk factor in African and Caucasian men. The study consisted of 101 urbanised African and 101 Caucasian male school teachers. We measured 24h ambulatory blood pressure and the carotid cross-sectional wall area, and determined left ventricular hypertrophy electrocardiographically by means of the Cornell product. Urinary albumin and creatinine were analysed to obtain the albumin-to-creatinine ratio. Africans had higher 24h, daytime and nighttime systolic- and diastolic blood pressure, heart rate and resultant double product compared to the Caucasians. In addition, markers of end-organ damage, albumin-to-creatinine ratio and left ventricular hypertrophy were higher in the Africans while cross-sectional wall area did not differ. In Africans after single partial and multiple regression analysis, 24h systolic blood pressure, but not double product or heart rate, correlated positively with markers of end-organ damage (cross-sectional wall area: β=0.398, P=0.005; left ventricular hypertrophy: β=0.455, P<0.001; albumin-to-creatinine ratio: β=0.280, P=0.012). No associations were evident in Caucasian men. Double product may not be a good marker of increased cardiovascular risk when compared to systolic blood pressure in African and Caucasian men. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Complications and Short-Term Explantation Rate Following Artificial Urinary Sphincter Implantation: Results from a Large Middle European Multi-Institutional Case Series.

PubMed

Kretschmer, Alexander; Hüsch, Tanja; Thomsen, Frauke; Kronlachner, Dominik; Obaje, Alice; Anding, Ralf; Pottek, Tobias; Rose, Achim; Olianas, Roberto; Friedl, Alexander; Hübner, Wilhelm; Homberg, Roland; Pfitzenmaier, Jesco; Grein, Ulrich; Queissert, Fabian; Naumann, Carsten Maik; Schweiger, Josef; Wotzka, Carola; Nyarangi-Dix, Joanne N; Hofmann, Torben; Seiler, Roland; Haferkamp, Axel; Bauer, Ricarda M

2016-01-01

Background/Aims/Objectives: To analyze perioperative complication and short-term explantation rates after perineal or penoscrotal single-cuff and double-cuff artificial urinary sphincter (AUS) implantation in a large middle European multi-institutional patient cohort. 467 male patients with stress urinary incontinence underwent implantation of a perineal single-cuff (n = 152), penoscrotal single-cuff (n = 99), or perineal double-cuff (n = 216) AUS between 2010 and 2012. Postoperative complications and 6-month explantation rates were assessed. For statistical analysis, Fisher's exact test and Kruskal-Wallis rank sum test, and a multiple logistic regression model were used (p < 0.05). Compared to perineal single-cuff AUS, penoscrotal single-cuff implantation led to significantly increased short-term explantation rates (8.6% (perineal) vs. 19.2% (penoscrotal), p = 0.019). The postoperative infection rate was significantly higher after double-cuff compared to single-cuff implantation (6.0% (single-cuff) vs. 13.9% (double-cuff), p = 0.019). The short-term explantation rate after primary double-cuff placement was 6.5% (p = 0.543 vs. perineal single-cuff). In multivariate analysis, the penoscrotal approach (p = 0.004), intraoperative complications (p = 0.005), postoperative bleeding (p = 0.011), and perioperative infection (p < 0.001) were independent risk factors for short-term explantation. Providing data from a large contemporary multi-institutional patient cohort from high-volume and low-volume institutions, our results reflect the current standard of care in middle Europe. We indicate that the penoscrotal approach is an independent risk factor for increased short-term explantation rates. © 2016 S. Karger AG, Basel.

Clusters of DNA damage induced by ionizing radiation: formation of short DNA fragments. II. Experimental detection

NASA Technical Reports Server (NTRS)

Rydberg, B.; Chatterjee, A. (Principal Investigator)

1996-01-01

The basic 30-nm chromatin fiber in the mammalian cell consists of an unknown (possibly helical) arrangement of nucleosomes, with about 1.2 kb of DNA per 10-nm length of fiber. Track-structure considerations suggest that interactions of single delta rays or high-LET particles with the chromatin fiber might result in the formation of multiple lesions spread over a few kilobases of DNA (see the accompanying paper: W.R. Holley and A. Chatterjee, Radiat. Res. 145, 188-199, 1996). In particular, multiple DNA double-strand breaks and single-strand breaks may form. To test this experimentally, primary human fibroblasts were labeled with [3H]thymidine and exposed at 0 degrees C to X rays or accelerated nitrogen or iron ions in the LET range of 97-440 keV/microns. DNA was isolated inside agarose plugs and subjected to agarose gel electrophoresis under conditions that allowed good separation of 0.1-2 kb size DNA. The bulk of DNA remained in the well or migrated only a small distance into the gel. It was found that DNA fragments in the expected size range were formed linearly with dose with an efficiency that increased with LET. A comparison of the yield of such fragments with the yield of total DNA double-strand breaks suggests that for the high-LET ions a substantial proportion (20-90%) of DNA double-strand breaks are accompanied within 0.1-2 kb by at least one additional DNA double-strand break. It is shown that these results are in good agreement with theoretical calculations based on treating the 30-nm chromatin fiber as the target for ionizing particles. Theoretical considerations also predict that the clusters will contain numerous single-strand breaks and base damages. It is proposed that such clusters be designated "regionally multiply damaged sites." Postirradiation incubation at 37 degrees C resulted in a decline in the number of short DNA fragments, suggesting a repair activity. The biological significance of regionally multiply damaged sites is presently unknown.

Comparison of posterior lumbar interbody fusion (PLIF) with autogenous bone chips and PLIF with cage for treatment of double-level isthmic spondylolisthesis.

PubMed

Song, Deyong; Chen, Zhong; Song, Dewei; Li, Zaixue

2015-11-01

Spondylolytic defects involving multiple vertebral levels are rare. It is reported that only 1.48% of patients with back pain were diagnosed with multi-level spondylolysis. The incidence of multiple-level spondylolisthesis is even rarer, so far there have been few reports of multi-level isthmic spondylolisthesis in the literature. The aim of this study is to evaluate clinical and radiological outcomes of two different fusion techniques for treatment of double-level isthmic spondylolisthesis. Fifty-four patients who were managed surgically for treatment of double-level symptomatic isthmic spondylolisthesis were included in this study. Between May 2004 and September 2012, 29 consecutive patients underwent posterior lumbar interbody fusion (PLIF) with autogenous bone chips (group I) at Foshan Hospital of Traditional Chinese Medicine, Guangdong, China. Between March 2005 and December 2013, 25 consecutive patients underwent PLIF with cage (group II) at Zhujiang Hospital of Southern Medical University, Guangdong, China. The mean follow-up periods were 27.2 and 26.8 months, respectively. The mean VAS scores of back and leg pain significantly decreased from 7.2 to 2.2 and 5.8 to 2.1 in the group I and from 7.0 to 1.9 and 6.1 to 1.8 in the group II, respectively. In the group I, mean ODI scores improved significantly from 54% to 14.2% and, in the group II, from 60% to 12.6%. In both groups, VAS and ODI scores significantly changed from pre- to postoperatively (p<0.001), but postoperative outcome between groups was statistically not significant. Solid union was observed in 27 of 29 patients (89.6%) in the group I and in 22 of 25 patients (88%) in the group II, without statistically significant differences (p>0.05). In both groups, changes in disc height, degree of listhesis, and whole lumbar lordosis between the pre- and postoperative periods were significant. Clinical and functional outcomes demonstrate no significant differences between groups in treating back and leg pain of adult patients with double-level isthmic spondylolisthesis. Copyright © 2015 Elsevier B.V. All rights reserved.

The multiple V-shaped double peeling of elastic thin films from elastic soft substrates

NASA Astrophysics Data System (ADS)

Menga, N.; Afferrante, L.; Pugno, N. M.; Carbone, G.

2018-04-01

In this paper, a periodic configuration of V-shaped double peeling process is investigated. Specifically, an elastic thin film is detached from a soft elastic material by applying multiple concentrated loads periodically distributed with spatial periodicity λ. The original Kendall's idea is extended to take into account the change in elastic energy occurring in the substrate when the detachment fronts propagate. The symmetric configuration typical of a V-peeling process causes the energy release rate to be sensitive to variations of the elastic energy stored in the soft substrate. This results in an enhancement of the adhesion strength because part of the external work required to trigger the peeling mechanism is converted in substrate elastic energy. A key role is played by both spatial periodicity λ and elasticity ratio E/Eh, between tape and substrate elastic moduli, in determining the conditions of stable adhesion. Indeed, the presence of multiple peeling fronts determines a modification of the mechanism of interaction, because deformations close to each peeling front are also affected by the stresses related to the other fronts. Results show that the energy release rate depends on the detached length of the tape so that conditions can be established which lead to an increase of the supported load compared to the classical peeling on rigid substrates. Finally, we also find that for any given value of the load per unit length, an optimum value of the wavelength λ exists that maximizes the tolerance of the system, before unstable propagation of the peeling front can occur.

Embolization of direct carotid cavernous fistulas with the novel double-balloon technique

PubMed Central

Niu, Yin; Li, Lin; Tang, Jun; Zhu, Gang

2015-01-01

Multiple endovascular management of direct carotid cavernous fistula (CCF) has been widely accepted as a treatment option. Embolization of the fistula with detachable balloons or thrombogenic coil-based occlusion has been the main choice to treat direct CCF, with good safety and efficacy. This study investigated the safety and efficacy of embolization of direct CCF with the novel double-balloon technique. A retrospective review of a prospective database on cerebral vascular disease was performed. We identified a total of five patients presenting with high-flow direct CCF. All patients were managed with transarterial embolization with the novel double-balloon technique. Three of the five patients were treated with two detachable balloons, and a completely occluded fistula with preservation of the internal carotid artery was achieved. Of the remaining two patients treated with more detachable balloons, one patient achieved a perfect outcome and the other one suffered from recurrent fistula due to balloon migration 3 weeks after embolization. During a follow-up period of 12–18 months, no symptoms reoccurred in any patient. Thus, the double-balloon treatment may be a promising method for CCF complete occlusion. This novel technique may bring more benefits in the following two cases: 1). A single inflated detachable balloon fails to completely occlude the CCF, which causing the next balloon can not pass into the fistula. 2). A giant CCF needs more balloons for fistula embolization. PMID:26586136

Determining Double Bond Position in Lipids Using Online Ozonolysis Coupled to Liquid Chromatography and Ion Mobility-Mass Spectrometry.

PubMed

Harris, Rachel A; May, Jody C; Stinson, Craig A; Xia, Yu; McLean, John A

2018-02-06

The increasing focus on lipid metabolism has revealed a need for analytical techniques capable of structurally characterizing lipids with a high degree of specificity. Lipids can exist as any one of a large number of double bond positional isomers, which are indistinguishable by single-stage mass spectrometry alone. Ozonolysis reactions coupled to mass spectrometry have previously been demonstrated as a means for localizing double bonds in unsaturated lipids. Here we describe an online, solution-phase reactor using ozone produced via a low-pressure mercury lamp, which generates aldehyde products diagnostic of cleavage at a particular double bond position. This flow-cell device is utilized in conjunction with structurally selective ion mobility-mass spectrometry. The lamp-mediated reaction was found to be effective for multiple lipid species in both positive and negative ionization modes, and the conversion efficiency from precursor to product ions was tunable across a wide range (20-95%) by varying the flow rate through the ozonolysis device. Ion mobility separation of the ozonolysis products generated additional structural information and revealed the presence of saturated species in a complex mixture. The method presented here is simple, robust, and readily coupled to existing instrument platforms with minimal modifications necessary. For these reasons, application to standard lipidomic workflows is possible and aids in more comprehensive structural characterization of a myriad of lipid species.

Dynamics of the formation of laser-induced periodic surface structures (LIPSS) upon femtosecond two-color double-pulse irradiation of metals, semiconductors, and dielectrics

NASA Astrophysics Data System (ADS)

Höhm, S.; Herzlieb, M.; Rosenfeld, A.; Krüger, J.; Bonse, J.

2016-06-01

In order to address the dynamics and physical mechanisms of LIPSS formation for three different classes of materials (metals, semiconductors, and dielectrics), two-color double-fs-pulse experiments were performed on Titanium, Silicon and Fused Silica. For that purpose a Mach-Zehnder interferometer generated polarization controlled (parallel or cross-polarized) double-pulse sequences at 400 nm and 800 nm wavelength, with inter-pulse delays up to a few picoseconds. Multiple of these two-color double-pulse sequences were collinearly focused by a spherical mirror to the sample surfaces. The fluence of each individual pulse (400 nm and 800 nm) was always kept below its respective ablation threshold and only the joint action of both pulses lead to the formation of LIPSS. Their resulting characteristics (periods, areas) were analyzed by scanning electron microscopy. The periods along with the LIPSS orientation allow a clear identification of the pulse which dominates the energy coupling to the material. For strong absorbing materials (Silicon, Titanium), a wavelength-dependent plasmonic mechanism can explain the delay-dependence of the LIPSS. In contrast, for dielectrics (Fused Silica) the first pulse always dominates the energy deposition and LIPSS orientation, supporting a non-plasmonic formation scenario. For all materials, these two-color experiments confirm the importance of the ultrafast energy deposition stage for LIPSS formation.

Single-molecule dilution and multiple displacement amplification for molecular haplotyping.

PubMed

Paul, Philip; Apgar, Josh

2005-04-01

Separate haploid analysis is frequently required for heterozygous genotyping to resolve phase ambiguity or confirm allelic sequence. We demonstrate a technique of single-molecule dilution followed by multiple strand displacement amplification to haplotype polymorphic alleles. Dilution of DNA to haploid equivalency, or a single molecule, is a simple method for separating di-allelic DNA. Strand displacement amplification is a robust method for non-specific DNA expansion that employs random hexamers and phage polymerase Phi29 for double-stranded DNA displacement and primer extension, resulting in high processivity and exceptional product length. Single-molecule dilution was followed by strand displacement amplification to expand separated alleles to microgram quantities of DNA for more efficient haplotype analysis of heterozygous genes.

Pulse shape discrimination for background rejection in germanium gamma-ray detectors

NASA Technical Reports Server (NTRS)

Feffer, P. T.; Smith, D. M.; Campbell, R. D.; Primbsch, J. H.; Lin, R. P.

1989-01-01

A pulse-shape discrimination (PSD) technique is developed to reject the beta-decay background resulting from activation of Ge gamma-ray detectors by cosmic-ray secondaries. These beta decays are a major source of background at 0.2-2 MeV energies in well shielded Ge detector systems. The technique exploits the difference between the detected current pulse shapes of single- and multiple-site energy depositions within the detector: beta decays are primarily single-site events, while photons at these energies typically Compton scatter before being photoelectrically absorbed to produce multiple-site events. Depending upon the amount of background due to sources other than beta decay, PSD can more than double the detector sensitivity.

Documentation for the machine-readable version of the SAO-HD-GC-DM cross index version 1983

NASA Technical Reports Server (NTRS)

Roman, N. G.; Warren, W. H., Jr.; Schofield, N., Jr.

1983-01-01

An updated and extended machine readable version of the Smithsonian Astrophysical Observatory star catalog (SAO) is described. A correction of all errors which were found since preparation of the original catalog which resulted from misidentifications and omissions of components in multiple star systems and missing Durchmusterung numbers (the common identifier) in the SAO Catalog are included and component identifications from the Index of Visual Double Stars (IDS) are appended to all multiple SAO entries with the same DM numbers, and lower case letter identifiers for supplemental BD stars are added. A total of 11,398 individual corrections and data additions is incorporated into the present version of the cross index.

Aerodynamic calculational methods for curved-blade Darrieus VAWT WECS

NASA Astrophysics Data System (ADS)

Templin, R. J.

1985-03-01

Calculation of aerodynamic performance and load distributions for curved-blade wind turbines is discussed. Double multiple stream tube theory, and the uncertainties that remain in further developing adequate methods are considered. The lack of relevant airfoil data at high Reynolds numbers and high angles of attack, and doubts concerning the accuracy of models of dynamic stall are underlined. Wind tunnel tests of blade airbrake configurations are summarized.

Characterizing SRAM Single Event Upset in Terms of Single and Double Node Charge Collection

NASA Technical Reports Server (NTRS)

Black, J. D.; Ball, D. R., II; Robinson, W. H.; Fleetwood, D. M.; Schrimpf, R. D.; Reed, R. A.; Black, D. A.; Warren, K. M.; Tipton, A. D.; Dodd, P. E.;

Cholesky-decomposed density MP2 with density fitting: Accurate MP2 and double-hybrid DFT energies for large systems

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

Maurer, Simon A.; Clin, Lucien; Ochsenfeld, Christian, E-mail: christian.ochsenfeld@uni-muenchen.de

2014-06-14

Our recently developed QQR-type integral screening is introduced in our Cholesky-decomposed pseudo-densities Møller-Plesset perturbation theory of second order (CDD-MP2) method. We use the resolution-of-the-identity (RI) approximation in combination with efficient integral transformations employing sparse matrix multiplications. The RI-CDD-MP2 method shows an asymptotic cubic scaling behavior with system size and a small prefactor that results in an early crossover to conventional methods for both small and large basis sets. We also explore the use of local fitting approximations which allow to further reduce the scaling behavior for very large systems. The reliability of our method is demonstrated on test sets formore » interaction and reaction energies of medium sized systems and on a diverse selection from our own benchmark set for total energies of larger systems. Timings on DNA systems show that fast calculations for systems with more than 500 atoms are feasible using a single processor core. Parallelization extends the range of accessible system sizes on one computing node with multiple cores to more than 1000 atoms in a double-zeta basis and more than 500 atoms in a triple-zeta basis.« less

Do cannabis-based medicinal extracts have general or specific effects on symptoms in multiple sclerosis? A double-blind, randomized, placebo-controlled study on 160 patients.

PubMed

Wade, Derick T; Makela, Petra; Robson, Philip; House, Heather; Bateman, Cynthia

2004-08-01

The objective was to determine whether a cannabis-based medicinal extract (CBME) benefits a range of symptoms due to multiple sclerosis (MS). A parallel group, double-blind, randomized, placebo-controlled study was undertaken in three centres, recruiting 160 outpatients with MS experiencing significant problems from at least one of the following: spasticity, spasms, bladder problems, tremor or pain. The interventions were oromucosal sprays of matched placebo, or whole plant CBME containing equal amounts of delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD) at a dose of 2.5-120 mg of each daily, in divided doses. The primary outcome measure was a Visual Analogue Scale (VAS) score for each patient's most troublesome symptom. Additional measures included VAS scores of other symptoms, and measures of disability, cognition, mood, sleep and fatigue. Following CBME the primary symptom score reduced from mean (SE) 74.36 (11.1) to 48.89 (22.0) following CBME and from 74.31 (12.5) to 54.79 (26.3) following placebo [ns]. Spasticity VAS scores were significantly reduced by CBME (Sativex) in comparison with placebo (P =0.001). There were no significant adverse effects on cognition or mood and intoxication was generally mild.

Pdgfrα functions in endothelial-derived cells to regulate neural crest cells and the development of the great arteries.

PubMed

Aghajanian, Haig; Cho, Young Kuk; Rizer, Nicholas W; Wang, Qiaohong; Li, Li; Degenhardt, Karl; Jain, Rajan

2017-09-01

Originating as a single vessel emerging from the embryonic heart, the truncus arteriosus must septate and remodel into the aorta and pulmonary artery to support postnatal life. Defective remodeling or septation leads to abnormalities collectively known as conotruncal defects, which are associated with significant mortality and morbidity. Multiple populations of cells must interact to coordinate outflow tract remodeling, and the cardiac neural crest has emerged as particularly important during this process. Abnormalities in the cardiac neural crest have been implicated in the pathogenesis of multiple conotruncal defects, including persistent truncus arteriosus, double outlet right ventricle and tetralogy of Fallot. However, the role of the neural crest in the pathogenesis of another conotruncal abnormality, transposition of the great arteries, is less well understood. In this report, we demonstrate an unexpected role of Pdgfra in endothelial cells and their derivatives during outflow tract development. Loss of Pdgfra in endothelium and endothelial-derived cells results in double outlet right ventricle and transposition of the great arteries. Our data suggest that loss of Pdgfra in endothelial-derived mesenchyme in the outflow tract endocardial cushions leads to a secondary defect in neural crest migration during development. © 2017. Published by The Company of Biologists Ltd.

Estimation of the quantification uncertainty from flow injection and liquid chromatography transient signals in inductively coupled plasma mass spectrometry

NASA Astrophysics Data System (ADS)

Laborda, Francisco; Medrano, Jesús; Castillo, Juan R.

2004-06-01

The quality of the quantitative results obtained from transient signals in high-performance liquid chromatography-inductively coupled plasma mass spectrometry (HPLC-ICPMS) and flow injection-inductively coupled plasma mass spectrometry (FI-ICPMS) was investigated under multielement conditions. Quantification methods were based on multiple-point calibration by simple and weighted linear regression, and double-point calibration (measurement of the baseline and one standard). An uncertainty model, which includes the main sources of uncertainty from FI-ICPMS and HPLC-ICPMS (signal measurement, sample flow rate and injection volume), was developed to estimate peak area uncertainties and statistical weights used in weighted linear regression. The behaviour of the ICPMS instrument was characterized in order to be considered in the model, concluding that the instrument works as a concentration detector when it is used to monitorize transient signals from flow injection or chromatographic separations. Proper quantification by the three calibration methods was achieved when compared to reference materials, although the double-point calibration allowed to obtain results of the same quality as the multiple-point calibration, shortening the calibration time. Relative expanded uncertainties ranged from 10-20% for concentrations around the LOQ to 5% for concentrations higher than 100 times the LOQ.

Ion Acceleration by Double Layers with Multi-Component Ion Species

NASA Astrophysics Data System (ADS)

Good, Timothy; Aguirre, Evan; Scime, Earl; West Virginia University Team

2017-10-01

Current-free double layers (CFDL) models have been proposed to explain observations of magnetic field-aligned ion acceleration in plasmas expanding into divergent magnetic field regions. More recently, experimental studies of the Bohm sheath criterion in multiple ion species plasma reveal an equilibration of Bohm speeds at the sheath-presheath boundary for a grounded plate in a multipole-confined filament discharge. We aim to test this ion velocity effect for CFDL acceleration. We report high resolution ion velocity distribution function (IVDF) measurements using laser induced fluorescence downstream of a CFDL in a helicon plasma. Combinations of argon-helium, argon-krypton, and argon-xenon gases are ionized and measurements of argon or xenon IVDFs are investigated to determine whether ion acceleration is enhanced (or diminished) by the presence of lighter (or heavier) ions in the mix. We find that the predominant effect is a reduction of ion acceleration consistent with increased drag arising from increased gas pressure under all conditions, including constant total gas pressure, equal plasma densities of different ions, and very different plasma densities of different ions. These results suggest that the physics responsible for acceleration of multiple ion species in simple sheaths is not responsible for the ion acceleration observed in these expanding plasmas. Department of Physics, Gettysburg College.

Irreparable complex DNA double-strand breaks induce chromosome breakage in organotypic three-dimensional human lung epithelial cell culture

PubMed Central

Asaithamby, Aroumougame; Hu, Burong; Delgado, Oliver; Ding, Liang-Hao; Story, Michael D.; Minna, John D.; Shay, Jerry W.; Chen, David J.

2011-01-01

DNA damage and consequent mutations initiate the multistep carcinogenic process. Differentiated cells have a reduced capacity to repair DNA lesions, but the biological impact of unrepaired DNA lesions in differentiated lung epithelial cells is unclear. Here, we used a novel organotypic human lung three-dimensional (3D) model to investigate the biological significance of unrepaired DNA lesions in differentiated lung epithelial cells. We showed, consistent with existing notions that the kinetics of loss of simple double-strand breaks (DSBs) were significantly reduced in organotypic 3D culture compared to kinetics of repair in two-dimensional (2D) culture. Strikingly, we found that, unlike simple DSBs, a majority of complex DNA lesions were irreparable in organotypic 3D culture. Levels of expression of multiple DNA damage repair pathway genes were significantly reduced in the organotypic 3D culture compared with those in 2D culture providing molecular evidence for the defective DNA damage repair in organotypic culture. Further, when differentiated cells with unrepaired DNA lesions re-entered the cell cycle, they manifested a spectrum of gross-chromosomal aberrations in mitosis. Our data suggest that downregulation of multiple DNA repair pathway genes in differentiated cells renders them vulnerable to DSBs, promoting genome instability that may lead to carcinogenesis. PMID:21421565

Differential Requirements for c-Myc in Chronic Hematopoietic Hyperplasia and Acute Hematopoietic Malignancies in Pten-null Mice

PubMed Central

Zhang, Jun; Xiao, Yechen; Guo, Yinshi; Breslin, Peter; Zhang, Shubin; Wei, Wei; Zhang, Zhou; Zhang, Jiwang

2011-01-01

Myeloproliferative disorders (MPDs), lymphoproliferative disorders (LPDs), acute T-lymphocytic or myeloid leukemia and T-lymphocytic lymphoma were developed in inducible Pten-knockout (Pten−/−) mice. The appearance of these multiple diseases in one animal model provides an opportunity to study the pathogenesis of multiple diseases simultaneously. To study whether Myc function is required for the development of these hematopoietic disorders in Pten−/− mice, we generated inducible Pten/Myc double-knockout mice (Pten−/−/Myc−/−). By comparing the hematopoietic phenotypes of these double-knockout mice with those of Pten−/− mice, we found that both sets of animals developed MPDs and LPDs. However, none of the compound-mutant mice developed acute leukemia or lymphoma. Interestingly, in contrast to the MPDs which developed in Pten−/− mice which are dominated by granulocytes, megakaryocytes predominate in the MPDs of Pten−/−/Myc−/− mice. Our study suggests that the deregulation of PI3K/Akt signaling in Pten−/− hematopoietic cells protects these cells from apoptotic cell death, resulting in chronic proliferative disorders. But due to the differential requirement for Myc in granulocyte as compared to megakaryocyte proliferation, Myc deletion converts Pten−/− MPDs from granulocyte-dominated to megakaryocyte-dominated conditions. Myc is absolutely required for the development of acute hematopoietic malignancies. PMID:21926961