Cardiorespiratory dynamic response to mental stress: a multivariate time-frequency analysis.

PubMed

Widjaja, Devy; Orini, Michele; Vlemincx, Elke; Van Huffel, Sabine

2013-01-01

Mental stress is a growing problem in our society. In order to deal with this, it is important to understand the underlying stress mechanisms. In this study, we aim to determine how the cardiorespiratory interactions are affected by mental arithmetic stress and attention. We conduct cross time-frequency (TF) analyses to assess the cardiorespiratory coupling. In addition, we introduce partial TF spectra to separate variations in the RR interval series that are linearly related to respiration from RR interval variations (RRV) that are not related to respiration. The performance of partial spectra is evaluated in two simulation studies. Time-varying parameters, such as instantaneous powers and frequencies, are derived from the computed spectra. Statistical analysis is carried out continuously in time to evaluate the dynamic response to mental stress and attention. The results show an increased heart and respiratory rate during stress and attention, compared to a resting condition. Also a fast reduction in vagal activity is noted. The partial TF analysis reveals a faster reduction of RRV power related to (3 s) than unrelated to (30 s) respiration, demonstrating that the autonomic response to mental stress is driven by mechanisms characterized by different temporal scales.

Jacobian projection reduced-order models for dynamic systems with contact nonlinearities

NASA Astrophysics Data System (ADS)

Gastaldi, Chiara; Zucca, Stefano; Epureanu, Bogdan I.

2018-02-01

In structural dynamics, the prediction of the response of systems with localized nonlinearities, such as friction dampers, is of particular interest. This task becomes especially cumbersome when high-resolution finite element models are used. While state-of-the-art techniques such as Craig-Bampton component mode synthesis are employed to generate reduced order models, the interface (nonlinear) degrees of freedom must still be solved in-full. For this reason, a new generation of specialized techniques capable of reducing linear and nonlinear degrees of freedom alike is emerging. This paper proposes a new technique that exploits spatial correlations in the dynamics to compute a reduction basis. The basis is composed of a set of vectors obtained using the Jacobian of partial derivatives of the contact forces with respect to nodal displacements. These basis vectors correspond to specifically chosen boundary conditions at the contacts over one cycle of vibration. The technique is shown to be effective in the reduction of several models studied using multiple harmonics with a coupled static solution. In addition, this paper addresses another challenge common to all reduction techniques: it presents and validates a novel a posteriori error estimate capable of evaluating the quality of the reduced-order solution without involving a comparison with the full-order solution.

The Work Softening by Deformation-Induced Disordering and Cold Rolling of 6.5 wt pct Si Steel Thin Sheets

NASA Astrophysics Data System (ADS)

Wang, Xianglong; Li, Haoze; Zhang, Weina; Liu, Zhenyu; Wang, Guodong; Luo, Zhonghan; Zhang, Fengquan

2016-09-01

As-cast strip of 6.5 wt pct Si steel was fabricated by twin-roll strip casting. After hot rolling at 1323 K (1050 °C), thin sheets with the thickness of 0.35 mm were produced by warm rolling at 373 K (100 °C) with rolling reductions of 15, 25, 35, 45, 55, and 65 pct. Influence of warm rolling reduction on ductility was investigated by room temperature bending test. The measurement of macro-hardness showed that "work softening" could begin when the warm rolling reduction exceeded 35 pct. The room temperature ductility of the thin sheets gradually increased with the increase of warm rolling reductions, and the plastic deformation during bending began to form when the warm rolling reduction was greater than 45 pct, the 65 pct rolled thin sheet exhibited the maximum plastic deformation of about 0.6 pct during bending at room temperature, with a few small dimples having been observed on the fracture surfaces. B2-ordered domains were formed in the 15, 25, 35, 45, and 55 pct rolled specimens, and their average size decreased with the increase of warm rolling reductions. By contrast, no B2-ordered domain could be found in the 65 pct rolled specimen. It had been observed that large-ordered domains could be split into several small parts by the slip of partial super-dislocations during warm rolling, which led to significant decrease of the order degree to cause the phenomenon of deformation-induced disordering. On the basis of these results, cold rolling schedule was developed to successfully fabricate 0.25-mm-thick sheets with good surface qualities and magnetic properties from warm rolled sheets.

Avalanches, plasticity, and ordering in colloidal crystals under compression.

PubMed

McDermott, D; Reichhardt, C J Olson; Reichhardt, C

2016-06-01

Using numerical simulations we examine colloids with a long-range Coulomb interaction confined in a two-dimensional trough potential undergoing dynamical compression. As the depth of the confining well is increased, the colloids move via elastic distortions interspersed with intermittent bursts or avalanches of plastic motion. In these avalanches, the colloids rearrange to minimize their colloid-colloid repulsive interaction energy by adopting an average lattice constant that is isotropic despite the anisotropic nature of the compression. The avalanches take the form of shear banding events that decrease or increase the structural order of the system. At larger compression, the avalanches are associated with a reduction of the number of rows of colloids that fit within the confining potential, and between avalanches the colloids can exhibit partially crystalline or anisotropic ordering. The colloid velocity distributions during the avalanches have a non-Gaussian form with power-law tails and exponents that are consistent with those found for the velocity distributions of gliding dislocations. We observe similar behavior when we subsequently decompress the system, and find a partially hysteretic response reflecting the irreversibility of the plastic events.

Poisson-Spot Intensity Reduction with a Partially-Transparent Petal-Shaped Optical Mask

NASA Technical Reports Server (NTRS)

Shiri, Shahram; Wasylkiwskyj, Wasyl

2013-01-01

The presence of Poisson's spot, also known as the spot of Arago, formed along the optical axis in the geometrical shadow behind an obstruction, has been known since the 18th century. The presence of this spot can best be described as the consequence of constructive interference of light waves diffracted on the edge of the obstruction where its central position can··be determined by the symmetry of the object More recently, the elimination of this spot has received attention in the fields of particle physics, high-energy lasers, astronomy and lithography. In this paper, we introduce a novel, partially transparent petaled mask shape that suppresses the bright spot by up to 10 orders of magnitude in intensity, with powerful applications to many of the above fields. The optimization technique formulated in this design can identify mask shapes having partial transparency only near the petal tips.

Carbon acceptor incorporation in GaAs grown by metalorganic chemical vapor deposition: Arsine versus tertiarybutylarsine

NASA Astrophysics Data System (ADS)

Watkins, S. P.; Haacke, G.

1991-10-01

Undoped p-type GaAs epilayers were grown by low-pressure metalorganic chemical vapor deposition (MOCVD) at 650 °C and 76 Torr using either arsine or tertiarybutylarsine (TBA), and trimethylgallium (TMG). Extremely high-purity precursors were used in order to eliminate extrinsic doping effects. Carbon acceptors from the TMG were the dominant residual electrical impurities under all growth conditions. Temperature-dependent Hall measurements were used to make a quantitative comparison of the carbon acceptor concentrations for arsine- and TBA-grown epilayers over a range of As partial pressures. For a given group V partial pressure, we report a significant reduction in carbon acceptor incorporation using TBA compared with arsine under identical growth conditions.

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

Choi, Cheong R.

The structural changes of kinetic Alfvén solitary waves (KASWs) due to higher-order terms are investigated. While the first-order differential equation for KASWs provides the dispersion relation for kinetic Alfvén waves, the second-order differential equation describes the structural changes of the solitary waves due to higher-order nonlinearity. The reductive perturbation method is used to obtain the second-order and third-order partial differential equations; then, Kodama and Taniuti's technique [J. Phys. Soc. Jpn. 45, 298 (1978)] is applied in order to remove the secularities in the third-order differential equations and derive a linear second-order inhomogeneous differential equation. The solution to this new second-ordermore » equation indicates that, as the amplitude increases, the hump-type Korteweg-de Vries solution is concentrated more around the center position of the soliton and that dip-type structures form near the two edges of the soliton. This result has a close relationship with the interpretation of the complex KASW structures observed in space with satellites.« less

A study of the kinetics of the reduction of neptunium(VI) by acetohydroxamic acid in perchloric acid

NASA Astrophysics Data System (ADS)

Matteson, Brent S.; Precek, Martin; Paulenova, Alena

2010-03-01

The kinetics of reduction of NpO22+ to NpO2+ by acetohydroxamic acid in 1 mol·L-1perchloric acid media at 10 and 22°C were studied. The reaction rate was monitored using stopped-flow and standard infrared spectroscopy. Under conditions such that acetohydroxamic acid was in excess relative to Np, the reduction rate of NpO22+ is described by the following: where k = 2.57x103 mol-1·L·sec-1 at 10°C. However, when neptunium is in a significant molar excess relative to acetohydroxamic acid, the reduction mechanism is dictated by two distinct reactions. An initial and incomplete reduction occurs as the result of the oxidation of AHA, while a slower and partial reduction of NpO22+ is likely caused by the oxidation products of AHA. The reaction rate of this first-order mechanism was calculated as 3.7x10-4 sec-1 at 10°C and 0.001 sec-1 at 22°C.

Multiscale modeling and experimental interpretation of perovskite oxide materials in thermochemical energy storage and conversion for application in concentrating solar power

NASA Astrophysics Data System (ADS)

Albrecht, Kevin J.

Decarbonization of the electric grid is fundamentally limited by the intermittency of renewable resources such as wind and solar. Therefore, energy storage will play a significant role in the future of grid-scale energy generation to overcome the intermittency issues. For this reason, concentrating solar power (CSP) plants have been a renewable energy generation technology of interest due to their ability to participate in cost effective and efficient thermal energy storage. However, the ability to dynamically dispatch a CSP plant to meet energy demands is currently limited by the large quantities of sensible thermal energy storage material needed in a molten salt plant. Perovskite oxides have been suggested as a thermochemical energy storage material to enhance the energy storage capabilities of particle-based CSP plants, which combine sensible and chemical modes of energy storage. In this dissertation, computational models are used to establish the thermochemical energy storage potential of select perovskite compositions, identify system configurations that promote high values of energy storage and solar-to-electric efficiency, assess the kinetic and transport limitation of the chemical mode of energy storage, and create receiver and reoxidation reactor models capable of aiding in component design. A methodology for determining perovskite thermochemical energy storage potential is developed based on point defect models to represent perovskite non-stoichiometry as a function of temperature and gas phase oxygen partial pressure. The thermodynamic parameters necessary for the model are extracted from non-stoichiometry measurements by fitting the model using an optimization routine. The procedure is demonstrated for Ca0.9Sr0.1MnO 3-d which displayed combined energy storage values of 705.7 kJ/kg -1 by cycling between 773 K and 0.21 bar oxygen to 1173 K and 10 -4 bar oxygen. Thermodynamic system-level models capable of exploiting perovskite redox chemistry for energy storage in CSP plants are presented. Comparisons of sweep gas and vacuum pumping reduction as well as hot storage conditions indicate that solar-to-electric efficiencies are higher for sweep gas reduction system at equivalent values of energy storage if the energy parasitics of commercially available devices are considered. However, if vacuum pump efficiency between 15% and 30% can be achieved, the reduction methods will be approximately equal. Reducing condition oxygen partial pressures below 10-3 bar for sweep gas reduction and 10-2 bar for vacuum pumping reduction result in large electrical parasitics, which significantly reduce solar-to-electric efficiency. A model based interpretation of experimental measurements made for perovskite redox cycling using sweep gas in a packed bed is presented. The model indicates that long reduction times for equilibrating perovskites with low oxygen partial pressure sweep gas, compared to reoxidation, are primarily due to the oxygen carrying capacity of high purity sweep gas and not surface kinetic limitations. Therefore, achieving rapid reduction in the limited receiver residence time will be controlled by the quantity of sweep gas introduced. Effective kinetic parameters considering surface reaction and radial particle diffusion are fit to the experimental data. Variable order rate expressions without significant particle radial diffusion limitations are shown to be capable of representing the reduction and oxidation data. Modeling of a particle reduction receiver using continuous flow of perovskite solid and sweep gas in counter-flow configuration has identified issues with managing the oxygen evolved by the solid as well as sweep gas flow rates. Introducing sweep gas quantities necessary for equilibrating the solid with oxygen partial pressures below 10-2 are shown to result in gas phase velocities above the entrainment velocity of 500 um particles. Receiver designs with considerations for gas management are investigated and the results indicate that degrees of reduction corresponding to only oxygen partial pressures of 10-2 bar are attained. Numerical investigation into perovskite thermochemical energy storage indicates that achieving high levels of reduction through sweep gas or vacuum pumping to lower gas phase oxygen partial pressure below 10-2 bar display issues with parasitic energy consumption and gas phase management. Therefore, focus on material development should place a premium on thermal reduction and reduction by shifting oxygen partial pressure between ambient and 10-2 bar. Such a material would enable the development of a system with high solar-to-electric efficiencies and degrees of reduction which are attainable in realistic component geometries.

Experimental assessment of spanwise-oscillating dielectric electroactive surfaces for turbulent drag reduction in an air channel flow

NASA Astrophysics Data System (ADS)

Gatti, Davide; Güttler, Andreas; Frohnapfel, Bettina; Tropea, Cameron

2015-05-01

In the present work, wall oscillations for turbulent skin friction drag reduction are realized in an air turbulent duct flow by means of spanwise-oscillating active surfaces based on dielectric electroactive polymers. The actuator system produces spanwise wall velocity oscillations of 820 mm/s semi-amplitude at its resonance frequency of 65 Hz while consuming an active power of a few 100 mW. The actuators achieved a maximum integral drag reduction of 2.4 %. The maximum net power saving, budget of the power benefit and cost of the control, was measured for the first time with wall oscillations. Though negative, the net power saving is order of magnitudes higher than what has been estimated in previous studies. Two new direct numerical simulations of turbulent channel flow show that the finite size of the actuator only partially explains the lower values of integral drag reduction typically achieved in laboratory experiments compared to numerical simulations.

Pressure dependence of the oxygen reduction reaction at the platinum microelectrode/nafion interface - Electrode kinetics and mass transport

NASA Technical Reports Server (NTRS)

Parthasarathy, Arvind; Srinivasan, Supramaniam; Appleby, A. J.; Martin, Charles R.

1992-01-01

The investigation of oxygen reduction kinetics at the platinum/Nafion interface is of great importance in the advancement of proton-exchange-membrane (PEM) fuel-cell technology. This study focuses on the dependence of the oxygen reduction kinetics on oxygen pressure. Conventional Tafel analysis of the data shows that the reaction order with respect to oxygen is unity at both high and low current densities. Chronoamperometric measurements of the transport parameters for oxygen in Nafion show that oxygen dissolution follows Henry's isotherm. The diffusion coefficient of oxygen is invariant with pressure; however, the diffusion coefficient for oxygen is lower when air is used as the equilibrating gas as compared to when oxygen is used for equilibration. These results are of value in understanding the influence of O2 partial pressure on the performance of PEM fuel cells and also in elucidating the mechanism of oxygen reduction at the platinum/Nafion interface.

Partial admission effect on the performance and vibration of a supersonic impulse turbine

NASA Astrophysics Data System (ADS)

Lee, Hang Gi; Shin, Ju Hyun; Choi, Chang-Ho; Jeong, Eunhwan; Kwon, Sejin

2018-04-01

This study experimentally investigates the effects of partial admission on the performance and vibration outcomes of a supersonic impulse turbine with circular nozzles. The turbine of a turbopump for a gas-generator-type liquid rocket engine in the Korea Space Launch Vehicle-II is of the supersonic impulse type with the partial admission configuration for obtaining a high specific power. Partial admission turbines with a low-flow-rate working gas exhibit benefits over turbines with full admission, such as loss reduction, ease of controllability of the turbine power output, and simple turbine configurations with separate starting sections. However, the radial force of the turbine rotor due to the partial admission causes an increase in turbine vibration. Few experimental studies have previously been conducted regarding the partial admission effects on supersonic impulse turbines with circular nozzles. In the present study, performance tests of supersonic impulse turbines with circular nozzles were conducted for various partial admission ratios using a turbine test facility with high-pressure air in order to investigate the resulting aerodynamic performance and vibration. Four types of turbines with partial admission ratios of 0.17, 0.42, 0.75 and 0.83 were tested. Results show that the efficiencies at the design point increase linearly as the partial admission ratios increase. Moreover, as the velocity ratios increase, the difference in efficiency from the reference turbine with a partial admission ratio of 0.83 becomes increasingly significant, and the magnitudes of these differences are proportional to the square of the velocity ratios. Likewise, the decrease in the partial admission ratio results in an increase in the turbine vibration level owing to the increase in the radial force.

76 FR 38206 - Public Land Order No. 7772; Partial Revocation of the Executive Order dated April 17, 1926; Idaho

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-29

... (IDI-35073)] Public Land Order No. 7772; Partial Revocation of the Executive Order dated April 17, 1926; Idaho AGENCY: Bureau of Land Management, Interior. ACTION: Public Land Order. SUMMARY: This order partially revokes a withdrawal created by an Executive Order insofar as it affects 369.68 acres of public...

Increased breath nitrous oxide after ingesting nitrate in patients with atrophic gastritis and partial gastrectomy.

PubMed

Mitsui, Takahiro; Kondo, Takaharu

2004-07-01

Toxic nitrite and N-nitroso compounds due to gastric bacterial growth are often detected in the stomach of patients with atrophic gastritis and partial gastrectomy. The aim of this study is to investigate whether breath N2O, a major metabolite of denitrification, detected after ingestion of nitrate is associated with atrophic gastritis and partial gastrectomy. Nine young, 16 normal older, nine atrophic gastritis and six partial gastrectomy subjects ingested 100 g lettuce, equal to 130 mg nitrate, and breath N2O was measured at 15-min intervals for 5 h. N2O was analyzed using an infrared-photoacoustic analyzer, and atrophic gastritis was diagnosed by pepsinogen test. The mean breath N2O concentrations were higher in the following order at all times: partial gastrectomy>atrophic gastritis>normal>young. The maximum N2O concentrations in the patients with partial gastrectomy and atrophic gastritis were 1655 +/- 296 and 1350 +/- 200 (mean +/- S.E.) ppb, respectively, which were higher than that of the normal subjects, 827 +/- 91 ppb (P < 0.05). The maximum N2O concentration in young people was 527 +/- 86 ppb, which was lower than that of the normal older people (P < 0.051). These higher N2O concentrations in gastric patients reflect bacterial growth in the stomach due to the reduction of gastric acid. Copyright 2004 Elsevier B.V.

Estimation of norovirus infection risks to consumers of wastewater-irrigated food crops eaten raw.

PubMed

Mara, Duncan; Sleigh, Andrew

2010-03-01

A quantitative microbial risk analysis-Monte Carlo method was used to estimate norovirus infection risks to consumers of wastewater-irrigated lettuce. Using the same assumptions as used in the 2006 WHO guidelines for the safe use of wastewater in agriculture, a norovirus reduction of 6 log units was required to achieve a norovirus infection risk of approximately 10(-3) per person per year (pppy), but for a lower consumption of lettuce (40-48 g per week vs. 350 g per week) the required reduction was 5 log units. If the tolerable additional disease burden is increased from a DALY (disability-adjusted life year) loss of 10(-6) pppy (the value used in the WHO guidelines) to 10(-5) pppy, the required pathogen reduction is one order of magnitude lower. Reductions of 4-6 log units can be achieved by very simple partial treatment (principally settling to achieve a 1-log unit reduction) supplemented by very reliable post-treatment health-protection control measures such as pathogen die-off (1-2 log units), produce washing in cold water (1 log unit) and produce disinfection (3 log units).

Breakdown of Magnetic Order in the Pressurized Kitaev Iridate β -Li2IrO3

NASA Astrophysics Data System (ADS)

Majumder, M.; Manna, R. S.; Simutis, G.; Orain, J. C.; Dey, T.; Freund, F.; Jesche, A.; Khasanov, R.; Biswas, P. K.; Bykova, E.; Dubrovinskaia, N.; Dubrovinsky, L. S.; Yadav, R.; Hozoi, L.; Nishimoto, S.; Tsirlin, A. A.; Gegenwart, P.

2018-06-01

Temperature-pressure phase diagram of the Kitaev hyperhoneycomb iridate β -Li2IrO3 is explored using magnetization, thermal expansion, magnetostriction, and muon spin rotation measurements, as well as single-crystal x-ray diffraction under pressure and ab initio calculations. The Néel temperature of β -Li2IrO3 increases with the slope of 0.9 K /GPa upon initial compression, but the reduction in the polarization field Hc reflects a growing instability of the incommensurate order. At 1.4 GPa, the ordered state breaks down upon a first-order transition, giving way to a new ground state marked by the coexistence of dynamically correlated and frozen spins. This partial freezing in the absence of any conspicuous structural defects may indicate the classical nature of the resulting pressure-induced spin liquid, an observation paralleled to the increase in the nearest-neighbor off-diagonal exchange Γ under pressure.

Characterization of a water-solid interaction in a partially ordered system.

PubMed

Chakravarty, Paroma; Lubach, Joseph W

2013-11-04

GNE068-PC, a developmental compound, was previously characterized to be mesomorphous, i.e. having long-range order associated with significant local molecular disorder (Chakravarty et. al., Mol. Pharmaceutics, accepted). The compound was exposed to moisture under different relative humidity conditions ranging from 11% to 60% RH at room temperature (RT) for 7 days, and the resultant product phases were characterized. The partially ordered sample progressively lost crystallinity (long-range order) and birefringence (orientational order) upon exposure to increasing RH conditions, leading to the formation of a completely disordered amorphous phase at 60% RH (RT). Long-range positional order was irrecoverable even after moisture removal from the sample exposed to 60% RH. This was attributed to replacement of residual ethyl acetate by water, the former being critical for maintenance of long-range order in the material. In addition, water sorption appeared to irreversibly alter the molecular orientation, thereby affecting sample birefringence. Solid-state NMR revealed increases in (1)H and (13)C spin-lattice relaxation times (T1) going from the mesomorphous phase to the fully amorphous phase. This was indicative of reduction in lattice mobility, likely due to the decreased motion of the aromatic portions of the molecule, in particular C17, which showed the most dramatic increase in (13)C T1. This is likely due to decrease in available free volume upon water sorption. Drying of the hydrated disordered phase showed somewhat greater mobility than the hydrated phase, likely due to increased relative free volume through removal of water. A water-solid interaction therefore irreversibly changed the solid-state makeup of GNE068-PC.

Mechanical principles of effects of botulinum toxin on muscle length-force characteristics: an assessment by finite element modeling.

PubMed

Turkoglu, Ahu N; Huijing, Peter A; Yucesoy, Can A

2014-05-07

Recent experiments involving muscle force measurements over a range of muscle lengths show that effects of botulinum toxin (BTX) are complex e.g., force reduction varies as a function of muscle length. We hypothesized that altered conditions of sarcomeres within active parts of partially paralyzed muscle is responsible for this effect. Using finite element modeling, the aim was to test this hypothesis and to study principles of how partial activation as a consequence of BTX affects muscle mechanics. In order to model the paralyzing effect of BTX, only 50% of the fascicles (most proximal, or middle, or most distal) of the modeled muscle were activated. For all muscle lengths, a vast majority of sarcomeres of these BTX-cases were at higher lengths than identical sarcomeres of the BTX-free muscle. Due to such "longer sarcomere effect", activated muscle parts show an enhanced potential of active force exertion (up to 14.5%). Therefore, a muscle force reduction originating exclusively from the paralyzed muscle fiber populations, is compromised by the changes of active sarcomeres leading to a smaller net force reduction. Moreover, such "compromise to force reduction" varies as a function of muscle length and is a key determinant of muscle length dependence of force reduction caused by BTX. Due to longer sarcomere effect, muscle optimum length tends to shift to a lower muscle length. Muscle fiber-extracellular matrix interactions occurring via their mutual connections along full peripheral fiber lengths (i.e., myofascial force transmission) are central to these effects. Our results may help improving our understanding of mechanisms of how the toxin secondarily affects the muscle mechanically. Copyright © 2014 Elsevier Ltd. All rights reserved.

Transmission of linearly polarized light in seawater: implications for polarization signaling.

PubMed

Shashar, Nadav; Sabbah, Shai; Cronin, Thomas W

2004-09-01

Partially linearly polarized light is abundant in the oceans. The natural light field is partially polarized throughout the photic range, and some objects and animals produce a polarization pattern of their own. Many polarization-sensitive marine animals take advantage of the polarization information, using it for tasks ranging from navigation and finding food to communication. In such tasks, the distance to which the polarization information propagates is of great importance. Using newly designed polarization sensors, we measured the changes in linear polarization underwater as a function of distance from a standard target. In the relatively clear waters surrounding coral reefs, partial (%) polarization decreased exponentially as a function of distance from the target, resulting in a 50% reduction of partial polarization at a distance of 1.25-3 m, depending on water quality. Based on these measurements, we predict that polarization sensitivity will be most useful for short-range (in the order of meters) visual tasks in water and less so for detecting objects, signals, or structures from far away. Navigation and body orientation based on the celestial polarization pattern are predicted to be limited to shallow waters as well, while navigation based on the solar position is possible through a deeper range.

78 FR 52561 - Public Land Order No. 7820; Partial Modification, Public Water Reserve No. 107; Utah

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-23

...-52455] Public Land Order No. 7820; Partial Modification, Public Water Reserve No. 107; Utah AGENCY: Bureau of Land Management, Interior. ACTION: Public Land Order. SUMMARY: This order partially modifies a withdrawal created by an Executive Order insofar as it affects 264.21 acres of public lands withdrawn from...

Standing spin-wave mode structure and linewidth in partially disordered hexagonal arrays of perpendicularly magnetized sub-micron Permalloy discs

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

Ross, N., E-mail: rossn2282@gmail.com; Kostylev, M., E-mail: mikhail.kostylev@uwa.edu.au; Stamps, R. L.

2014-09-21

Standing spin wave mode frequencies and linewidths in partially disordered perpendicular magnetized arrays of sub-micron Permalloy discs are measured using broadband ferromagnetic resonance and compared to analytical results from a single, isolated disc. The measured mode structure qualitatively reproduces the structure expected from the theory. Fitted demagnetizing parameters decrease with increasing array disorder. The frequency difference between the first and second radial modes is found to be higher in the measured array systems than predicted by theory for an isolated disc. The relative frequencies between successive spin wave modes are unaffected by reduction of the long-range ordering of discs inmore » the array. An increase in standing spin wave resonance linewidth at low applied magnetic fields is observed and grows more severe with increased array disorder.« less

Intraperitoneal implant of recombinant encapsulated cells overexpressing alpha-L-iduronidase partially corrects visceral pathology in mucopolysaccharidosis type I mice.

PubMed

Baldo, Guilherme; Mayer, Fabiana Quoos; Martinelli, Barbara; Meyer, Fabiola Schons; Burin, Maira; Meurer, Luise; Tavares, Angela Maria Vicente; Giugliani, Roberto; Matte, Ursula

2012-08-01

Mucopolysaccharidosis type I (MPS I) is characterized by deficiency of the enzyme alpha-L-iduronidase (IDUA) and storage of glycosaminoglycans (GAG) in several tissues. Current available treatments present limitations, thus the search for new therapies. Encapsulation of recombinant cells within polymeric structures combines gene and cell therapy and is a promising approach for treating MPS I. We produced alginate microcapsules containing baby hamster kidney (BHK) cells overexpressing IDUA and implanted these capsules in the peritoneum of MPS I mice. An increase in serum and tissue IDUA activity was observed at early time-points, as well as a reduction in GAG storage; however, correction in the long term was only partially achieved, with a drop in the IDUA activity being observed a few weeks after the implant. Analysis of the capsules obtained from the peritoneum revealed inflammation and a pericapsular fibrotic process, which could be responsible for the reduction in IDUA levels observed in the long term. In addition, treated mice developed antibodies against the enzyme. The results suggest that the encapsulation process is effective in the short term but improvements must be achieved in order to reduce the immune response and reach a stable correction.

A mixed finite difference/Galerkin method for three-dimensional Rayleigh-Benard convection

NASA Technical Reports Server (NTRS)

Buell, Jeffrey C.

1988-01-01

A fast and accurate numerical method, for nonlinear conservation equation systems whose solutions are periodic in two of the three spatial dimensions, is presently implemented for the case of Rayleigh-Benard convection between two rigid parallel plates in the parameter region where steady, three-dimensional convection is known to be stable. High-order streamfunctions secure the reduction of the system of five partial differential equations to a system of only three. Numerical experiments are presented which verify both the expected convergence rates and the absolute accuracy of the method.

29Si nuclear magnetic resonance study of URu 2Si 2 under pressure

DOE PAGES

Shirer, K. R.; Dioguardi, A. P.; Bush, B. T.; ...

2015-12-01

Here, we report 29Si nuclear magnetic resonance measurements of single crystals and aligned powders of URu 2Si 2 under pressure in the hidden order and paramagnetic phases. We find evidence for a reduction of the Knight shift with applied pressure, consistent with previous measurements of the static magnetic susceptibility. Previous measurements of the spin lattice relaxation time revealed a partial suppression of the density of states below 30 K. Here, we find that the temperature at which this suppression occurs is enhanced with applied pressure.

Entropic manifestations of topological order in three dimensions

NASA Astrophysics Data System (ADS)

Bullivant, Alex; Pachos, Jiannis K.

2016-03-01

We evaluate the entanglement entropy of exactly solvable Hamiltonians corresponding to general families of three-dimensional topological models. We show that the modification to the entropic area law due to three-dimensional topological properties is richer than the two-dimensional case. In addition to the reduction of the entropy caused by a nonzero vacuum expectation value of contractible loop operators, a topological invariant emerges that increases the entropy if the model consists of nontrivially braiding anyons. As a result the three-dimensional topological entanglement entropy provides only partial information about the two entropic topological invariants.

Degradation of environment pollutant dyes using phytosynthesized metal nanocatalysts

NASA Astrophysics Data System (ADS)

MeenaKumari, M.; Philip, Daizy

2015-01-01

We present for the first time biogenic reduction and stabilization of gold and silver ions at room temperature using fruit juice of Punica granatum. The formation, morphology and crystalline structure of the synthesized nanoparticles are determined using UV-Visible, XRD and TEM. An attempt to reveal the partial role of phenolic hydroxyls in the reduction of Au3+ and Ag+ is done through FTIR analysis. The synthesized nanoparticles are used as potential catalysts in the degradation of a cationic phenothiazine dye, an anionic mono azo dye and a cationic fluorescent dye. The calculated values of percentage removal of dyes and the rate constants from pseudo first order kinetic data fit give a comparative study on degradation of organic dyes in presence of prepared gold and silver nanoparticles.

Model Order Reduction Algorithm for Estimating the Absorption Spectrum

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

Van Beeumen, Roel; Williams-Young, David B.; Kasper, Joseph M.

The ab initio description of the spectral interior of the absorption spectrum poses both a theoretical and computational challenge for modern electronic structure theory. Due to the often spectrally dense character of this domain in the quantum propagator’s eigenspectrum for medium-to-large sized systems, traditional approaches based on the partial diagonalization of the propagator often encounter oscillatory and stagnating convergence. Electronic structure methods which solve the molecular response problem through the solution of spectrally shifted linear systems, such as the complex polarization propagator, offer an alternative approach which is agnostic to the underlying spectral density or domain location. This generality comesmore » at a seemingly high computational cost associated with solving a large linear system for each spectral shift in some discretization of the spectral domain of interest. In this work, we present a novel, adaptive solution to this high computational overhead based on model order reduction techniques via interpolation. Model order reduction reduces the computational complexity of mathematical models and is ubiquitous in the simulation of dynamical systems and control theory. The efficiency and effectiveness of the proposed algorithm in the ab initio prediction of X-ray absorption spectra is demonstrated using a test set of challenging water clusters which are spectrally dense in the neighborhood of the oxygen K-edge. On the basis of a single, user defined tolerance we automatically determine the order of the reduced models and approximate the absorption spectrum up to the given tolerance. We also illustrate that, for the systems studied, the automatically determined model order increases logarithmically with the problem dimension, compared to a linear increase of the number of eigenvalues within the energy window. Furthermore, we observed that the computational cost of the proposed algorithm only scales quadratically with respect to the problem dimension.« less

Competing four-wave mixing processes in dispersion oscillating telecom fiber.

PubMed

Finot, Christophe; Fatome, Julien; Sysoliatin, Alexej; Kosolapov, A; Wabnitz, Stefan

2013-12-15

We experimentally study the dynamics of the generation of multiple sidebands by means of a quasi-phase-matched four-wave mixing (FWM) process occurring in a dispersion-oscillating, highly nonlinear optical fiber. The fiber under test is pumped by a ns microchip laser operating in the normal average group-velocity dispersion regime and in the telecom C band. We reveal that the growth of higher-order sidebands is strongly influenced by the competition with cascade FWM between the pump and the first-order quasi-phase matched sidebands. The properties of these competing FWM processes are substantially affected when a partially coherent pump source is used, leading to a drastic reduction of the average power needed for sideband generation.

Explanation-based generalization of partially ordered plans

NASA Technical Reports Server (NTRS)

Kambhampati, Subbarao; Kedar, Smadar

1991-01-01

Most previous work in analytic generalization of plans dealt with totally ordered plans. These methods cannot be directly applied to generalizing partially ordered plans, since they do not capture all interactions among plan operators for all total orders of such plans. We introduce a new method for generalizing partially ordered plans. This method is based on providing explanation-based generalization (EBG) with explanations which systematically capture the interactions among plan operators for all the total orders of a partially-ordered plan. The explanations are based on the Modal Truth Criterion which states the necessary and sufficient conditions for ensuring the truth of a proposition at any point in a plan, for a class of partially ordered plans. The generalizations obtained by this method guarantee successful and interaction-free execution of any total order of the generalized plan. In addition, the systematic derivation of the generalization algorithms from the Modal Truth Criterion obviates the need for carrying out a separate formal proof of correctness of the EBG algorithms.

Reduction in spread of excitation from current focusing at multiple cochlear locations in cochlear implant users.

PubMed

Padilla, Monica; Landsberger, David M

2016-03-01

Channel interaction from a broad spread of excitation is likely to be a limiting factor in performance by cochlear implant users. Although partial tripolar stimulation has been shown to reduce spread of excitation, the magnitude of the reduction is highly variable across subjects. Because the reduction in spread of excitation is typically only measured at one electrode for a given subject, the degree of variability across cochlear locations is unknown. The first goal of the present study was to determine if the reduction in spread of excitation observed from partial tripolar current focusing systematically varies across the cochlea. The second goal was to measure the variability in reduction of spread of excitation relative to monopolar stimulation across the cochlea. The third goal was to expand upon previous results that suggest that scaling of verbal descriptors can be used to predict the reduction in spread of excitation, by increasing the limited number of sites previously evaluated and verify the relationships remain with the larger dataset. The spread of excitation for monopolar and partial tripolar stimulation was measured at 5 cochlear locations using a psychophysical forward masking task. Results of the present study suggest that although partial tripolar stimulation typically reduces spread of excitation, the degree of reduction in spread of excitation was found to be highly variable and no effect of cochlear location was found. Additionally, subjective scaling of certain verbal descriptors (Clean/Dirty, Pure/Noisy) correlated with the reduction in spread of excitation suggesting sound quality scaling might be used as a quick clinical estimate of channels providing a reduction in spread of excitation. This quick scaling technique might help clinicians determine which patients would be most likely to benefit from a focused strategy. Copyright © 2016 Elsevier B.V. All rights reserved.

Reduction in Spread of Excitation from Current Focusing at Multiple Cochlear Locations in Cochlear Implant Users

PubMed Central

Padilla, Monica; Landsberger, David M.

2016-01-01

Channel interaction from a broad spread of excitation is likely to be a limiting factor in performance by cochlear implant users. Although partial tripolar stimulation has been shown to reduce spread of excitation, the magnitude of the reduction is highly variable across subjects. Because the reduction in spread of excitation is typically only measured at one electrode for a given subject, the degree of variability across cochlear locations is unknown. The first goal of the present study was to determine if the reduction in spread of excitation observed from partial tripolar current focusing systematically varies across the cochlea. The second goal was to measure the variability in reduction of spread of excitation relative to monopolar stimulation across the cochlea. The third goal was to expand upon previous results that suggest that scaling of verbal descriptors can be used to predict the reduction in spread of excitation, by increasing the limited number of sites previously evaluated and verify the relationships remain with the larger dataset. The spread of excitation for monopolar and partial tripolar stimulation was measured at 5 cochlear locations using a psychophysical forward masking task. Results of the present study suggest that although partial tripolar stimulation typically reduces spread of excitation, the degree of reduction in spread of excitation was found to be highly variable and no effect of cochlear location was found. Additionally, subjective scaling of certain verbal descriptors (Clean/Dirty, Pure/Noisy) correlated with the reduction in spread of excitation suggesting sound quality scaling might be used as a quick clinical estimate of channels providing a reduction in spread of excitation. This quick scaling technique might help clinicians determine which patients would be most likely to benefit from a focused strategy. PMID:26778546

Conformal and covariant Z4 formulation of the Einstein equations: Strongly hyperbolic first-order reduction and solution with discontinuous Galerkin schemes

NASA Astrophysics Data System (ADS)

Dumbser, Michael; Guercilena, Federico; Köppel, Sven; Rezzolla, Luciano; Zanotti, Olindo

2018-04-01

We present a strongly hyperbolic first-order formulation of the Einstein equations based on the conformal and covariant Z4 system (CCZ4) with constraint-violation damping, which we refer to as FO-CCZ4. As CCZ4, this formulation combines the advantages of a conformal and traceless formulation, with the suppression of constraint violations given by the damping terms, but being first order in time and space, it is particularly suited for a discontinuous Galerkin (DG) implementation. The strongly hyperbolic first-order formulation has been obtained by making careful use of first and second-order ordering constraints. A proof of strong hyperbolicity is given for a selected choice of standard gauges via an analytical computation of the entire eigenstructure of the FO-CCZ4 system. The resulting governing partial differential equations system is written in nonconservative form and requires the evolution of 58 unknowns. A key feature of our formulation is that the first-order CCZ4 system decouples into a set of pure ordinary differential equations and a reduced hyperbolic system of partial differential equations that contains only linearly degenerate fields. We implement FO-CCZ4 in a high-order path-conservative arbitrary-high-order-method-using-derivatives (ADER)-DG scheme with adaptive mesh refinement and local time-stepping, supplemented with a third-order ADER-WENO subcell finite-volume limiter in order to deal with singularities arising with black holes. We validate the correctness of the formulation through a series of standard tests in vacuum, performed in one, two and three spatial dimensions, and also present preliminary results on the evolution of binary black-hole systems. To the best of our knowledge, these are the first successful three-dimensional simulations of moving punctures carried out with high-order DG schemes using a first-order formulation of the Einstein equations.

Oxygen partial pressure dependence of thermoelectric power factor in polycrystalline n-type SrTiO3: Consequences for long term stability in thermoelectric oxides

NASA Astrophysics Data System (ADS)

Sharma, Peter A.; Brown-Shaklee, Harlan J.; Ihlefeld, Jon F.

2017-04-01

The Seebeck coefficient and electrical conductivity have been measured as functions of oxygen partial pressure over the range of 10-22 to 10-1 atm at 1173 K for a 10% niobium-doped SrTiO3 ceramic with a grain size comparable to the oxygen diffusion length. Temperature-dependent measurements performed from 320 to 1275 K for as-prepared samples reveal metallic-like conduction and good thermoelectric properties. However, upon exposure to progressively increasing oxygen partial pressure, the thermoelectric power factor decreased over time scales of 24 h, culminating in a three order of magnitude reduction over the entire operating range. Identical measurements on single crystal samples show negligible changes in the power factor so that the instability of ceramic samples is primarily tied to the kinetics of grain boundary diffusion. This work provides a framework for understanding the stability of thermoelectric properties in oxides under different atmospheric conditions. The control of the oxygen atmosphere remains a significant challenge in oxide thermoelectrics.

Clinical outcome of trans-sacral interbody fusion after partial reduction for high-grade l5-s1 spondylolisthesis.

PubMed

Smith, J A; Deviren, V; Berven, S; Kleinstueck, F; Bradford, D S

2001-10-15

A clinical retrospective study was conducted. To evaluate the clinical and radiographic outcome of reduction followed by trans-sacral interbody fusion for high-grade spondylolisthesis. In situ posterior interbody fusion with fibula allograft has improved the fusion rates for patients with high-grade spondylolisthesis. The use of this technique in conjunction with partial reduction has not been reported. Nine consecutive patients underwent treatment of high-grade (Grade 3 or 4) spondylolisthesis with partial reduction followed by posterior interbody fusion using cortical allograft. The average age at the time of surgery was 27 years (range, 8-51 years), and the average follow-up period was 43 months (range, 24-72 months). Before surgery, eight patients had low back pain, seven patients had radiating leg pain, and five patients had hamstring tightness. The average grade of spondylolisthesis by Meyerding grading was 3.9 (range, 3-5). Charts and radiographs were evaluated, and outcomes were collected by use of the modified SRS outcomes instrument. Radiographic indexes demonstrated significant improvement with partial reduction and fusion. The slip angle, as measured from the inferior endplate of L5, improved from 41.2 degrees (range, 24-82 degrees ) before surgery to 21 degrees (range, 5-40 degrees ) after surgery. All the patients were extremely or somewhat satisfied with surgery. The two patients who underwent this operation without initial instrumentation experienced fractures of their interbody grafts. Both of these patients underwent repair of the pseudarthrosis with placement of trans-sacral pedicle screw instrumentation and subsequent fusion. Partial reduction followed by posterior interbody fusion is an effective technique for the management of high-grade spondylolisthesis in pediatric and adult patient populations, as assessed by radiographic and clinical criteria. Pedicle screw instrumentation with the sacral screws capturing L5 is recommended when this technique is used for the treatment of high-grade spondylolisthesis. According to the clinical and radiographic results from this study, partial reduction and posterior fibula interbody fusion supplemented with pedicle screw instrumentation is an effective technique for select patients with high-grade spondylolisthesis at L5-S1.

Sparse partial least squares regression for simultaneous dimension reduction and variable selection

PubMed Central

Chun, Hyonho; Keleş, Sündüz

2010-01-01

Partial least squares regression has been an alternative to ordinary least squares for handling multicollinearity in several areas of scientific research since the 1960s. It has recently gained much attention in the analysis of high dimensional genomic data. We show that known asymptotic consistency of the partial least squares estimator for a univariate response does not hold with the very large p and small n paradigm. We derive a similar result for a multivariate response regression with partial least squares. We then propose a sparse partial least squares formulation which aims simultaneously to achieve good predictive performance and variable selection by producing sparse linear combinations of the original predictors. We provide an efficient implementation of sparse partial least squares regression and compare it with well-known variable selection and dimension reduction approaches via simulation experiments. We illustrate the practical utility of sparse partial least squares regression in a joint analysis of gene expression and genomewide binding data. PMID:20107611

Techno-economics of integrating bioethanol production from spent sulfite liquor for reduction of greenhouse gas emissions from sulfite pulping mills.

PubMed

Petersen, Abdul M; Haigh, Kate; Görgens, Johann F

2014-01-01

Flow sheet options for integrating ethanol production from spent sulfite liquor (SSL) into the acid-based sulfite pulping process at the Sappi Saiccor mill (Umkomaas, South Africa) were investigated, including options for generation of thermal and electrical energy from onsite bio-wastes, such as bark. Processes were simulated with Aspen Plus® for mass- and energy-balances, followed by an estimation of the economic viability and environmental impacts. Various concentration levels of the total dissolved solids in magnesium oxide-based SSL, which currently fuels a recovery boiler, prior to fermentation was considered, together with return of the fermentation residues (distillation bottoms) to the recovery boiler after ethanol separation. The generation of renewable thermal and electrical energy from onsite bio-wastes were also included in the energy balance of the combined pulping-ethanol process, in order to partially replace coal consumption. The bio-energy supplementations included the combustion of bark for heat and electricity generation and the bio-digestion of the calcium oxide SSL to produce methane as additional energy source. Ethanol production from SSL at the highest substrate concentration was the most economically feasible when coal was used for process energy. However this solution did not provide any savings in greenhouse gas (GHG) emissions for the concentration-fermentation-distillation process. Maximizing the use of renewable energy sources to partially replace coal consumption yielded a satisfactory economic performance, with a minimum ethanol selling price of 0.83 US$/l , and a drastic reduction in the overall greenhouse gas emissions for the entire facility. High substrate concentrations and conventional distillation should be used when considering integrating ethanol production at sulfite pulping mills. Bio-wastes generated onsite should be utilized at their maximum potential for energy generation in order to maximize the GHG emissions reduction.

Exploring Partial Order of European Countries

ERIC Educational Resources Information Center

Annoni, Paola; Bruggemann, Rainer

2009-01-01

Partial Order Theory has been recently more and more employed in applied science to overcome the intrinsic disadvantage hidden in aggregation, if a multiple attribute system is available. Despite its numerous positive features, there are many practical cases where the interpretation of the partial order can be rather troublesome. In these cases…

Comparison of various advanced oxidation processes for the degradation of 4-chloro-2 nitrophenol.

PubMed

Saritha, P; Aparna, C; Himabindu, V; Anjaneyulu, Y

2007-11-19

In the present study an attempt is made efficiently to degrade USEPA listed 4-chloro-2-nitrophenol (4C-2-NP), widely available in bulk drug and pesticide wastes using various advanced oxidation processes (AOPs). A comparative assessment using various AOPs (UV, H(2)O(2,) UV/H(2)O(2), Fenton, UV/Fenton and UV/TiO(2)) was attempted after initial optimization studies, viz., varying pH, peroxide concentration, iron concentration, and TiO(2) loading. The degradation of the study compound was estimated using chemical oxygen demand (COD) reduction and compound reduction using spectrophotometric methods and further validated with high performance liquid chromatography (HPLC). The degradation trends followed the order: UV/Fenton > UV/TiO(2) > UV/H(2)O(2) > Fenton > H(2)O(2) > UV(.) It can be inferred from the studies that UV/Fenton was the most effective in partial mineralization of 4C-2-NP. However, lower costs were obtained with H(2)O(2). Kinetic constants were evaluated using first order equations to determine the rate constant K.

Spatiotemporal control to eliminate cardiac alternans using isostable reduction

NASA Astrophysics Data System (ADS)

Wilson, Dan; Moehlis, Jeff

2017-03-01

Cardiac alternans, an arrhythmia characterized by a beat-to-beat alternation of cardiac action potential durations, is widely believed to facilitate the transition from normal cardiac function to ventricular fibrillation and sudden cardiac death. Alternans arises due to an instability of a healthy period-1 rhythm, and most dynamical control strategies either require extensive knowledge of the cardiac system, making experimental validation difficult, or are model independent and sacrifice important information about the specific system under study. Isostable reduction provides an alternative approach, in which the response of a system to external perturbations can be used to reduce the complexity of a cardiac system, making it easier to work with from an analytical perspective while retaining many of its important features. Here, we use isostable reduction strategies to reduce the complexity of partial differential equation models of cardiac systems in order to develop energy optimal strategies for the elimination of alternans. Resulting control strategies require significantly less energy to terminate alternans than comparable strategies and do not require continuous state feedback.

The Artificial Hamiltonian, First Integrals, and Closed-Form Solutions of Dynamical Systems for Epidemics

NASA Astrophysics Data System (ADS)

Naz, Rehana; Naeem, Imran

2018-03-01

The non-standard Hamiltonian system, also referred to as a partial Hamiltonian system in the literature, of the form {\\dot q^i} = {partial H}/{partial {p_i}},\\dot p^i = - {partial H}/{partial {q_i}} + {Γ ^i}(t,{q^i},{p_i}) appears widely in economics, physics, mechanics, and other fields. The non-standard (partial) Hamiltonian systems arise from physical Hamiltonian structures as well as from artificial Hamiltonian structures. We introduce the term `artificial Hamiltonian' for the Hamiltonian of a model having no physical structure. We provide here explicitly the notion of an artificial Hamiltonian for dynamical systems of ordinary differential equations (ODEs). Also, we show that every system of second-order ODEs can be expressed as a non-standard (partial) Hamiltonian system of first-order ODEs by introducing an artificial Hamiltonian. This notion of an artificial Hamiltonian gives a new way to solve dynamical systems of first-order ODEs and systems of second-order ODEs that can be expressed as a non-standard (partial) Hamiltonian system by using the known techniques applicable to the non-standard Hamiltonian systems. We employ the proposed notion to solve dynamical systems of first-order ODEs arising in epidemics.

Structural evolution of the double perovskites Sr{sub 2}B'UO{sub 6} (B' = Mn, Fe, Co, Ni, Zn) upon reduction: Magnetic behavior of the uranium cations

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

Pinacca, R.M., E-mail: rmp@unsl.edu.ar; Viola, M.C.; Pedregosa, J.C.

2011-11-15

Highlights: {yields} Evolution of the double perovskites Sr{sub 2}B'UO{sub 6} upon reduction were studied by XRPD. {yields} Orthorhombic (Pnma) disordered perovskites SrB'{sub 0.5-x}U{sub 0.5+x}O{sub 3} were obtained at 900 {sup o}C. {yields} U{sup 5+/4+} and Zn{sup 2+} cations are distributed at random over the octahedral positions. {yields} AFM ordering for the perovskite with B' = Zn appears below 30 K. -- Abstract: We describe the preparation of five perovskite oxides obtained upon reduction of Sr{sub 2}B'UO{sub 6} (B' = Mn, Fe, Co, Ni, Zn) with H{sub 2}/N{sub 2} (5%/95%) at 900 {sup o}C during 8 h, and their structural characterizationmore » by X-ray powder diffraction (XRPD). During the reduction process there is a partial segregation of the elemental metal when B' = Co, Ni, Fe, and the corresponding B'O oxide when B' = Mn, Zn. Whereas the parent, oxygen stoichiometric double perovskites Sr{sub 2}B'UO{sub 6} are long-range ordered concerning B' and U cations. The crystal structures of the reduced phases, SrB'{sub 0.5-x}U{sub 0.5+x}O{sub 3} with 0.37 < x < 0.27, correspond to simple, disordered perovskites; they are orthorhombic, space group Pnma (No. 62), with a full cationic disorder at the B site. Magnetic measurements performed on the phase with B' = Zn, indicate uncompensated antiferromagnetic ordering of the U{sup 5+}/U{sup 4+} sublattice below 30 K.« less

Isotonic designs for phase I trials in partially ordered groups.

PubMed

Conaway, Mark

2017-10-01

Dose-finding trials can be conducted such that patients are first stratified into multiple risk groups before doses are allocated. The risk groups are often completely ordered in that, for a fixed dose, the probability of toxicity is monotonically increasing across groups. In some trials, the groups are only partially ordered. For example, one of several groups in a trial may be known to have the least risk of toxicity for a given dose, but the ordering of the risk among the remaining groups may not be known. The aim of the article is to introduce a method for designing dose-finding trials of cytotoxic agents in completely or partially ordered groups of patients. This article presents a method for dose-finding that combines previously proposed mathematical models, augmented with results using order restricted inference. The resulting method is computationally convenient and allows for dose-finding in trials with completely or partially ordered groups. Extensive simulations are done to evaluate the performance of the method, using randomly generated dose-toxicity curves where, within each group, the risk of toxicity is an increasing function of dose. Our simulations show that the hybrid method, in which order-restricted estimation is applied to parameters of a parsimonious mathematical model, gives results that are similar to previously proposed methods for completely ordered groups. Our method generalizes to a wide range of partial orders among the groups. The problem of dose-finding in partially ordered groups has not been extensively studied in the statistical literature. The proposed method is computationally feasible, and provides a potential solution to the design of dose-finding studies in completely or partially ordered groups.

Transformers: the changing phases of low-dimensional vanadium oxide bronzes.

PubMed

Marley, Peter M; Horrocks, Gregory A; Pelcher, Kate E; Banerjee, Sarbajit

2015-03-28

In this feature article, we explore the electronic and structural phase transformations of ternary vanadium oxides with the composition MxV2O5 where M is an intercalated cation. The periodic arrays of intercalated cations ordered along quasi-1D tunnels or layered between 2D sheets of the V2O5 framework induce partial reduction of the framework vanadium atoms giving rise to charge ordering patterns that are specific to the metal M and stoichiometry x. This periodic charge ordering makes these materials remarkably versatile platforms for studying electron correlation and underpins the manifestation of phenomena such as colossal metal-insulator transitions, quantized charge corrals, and superconductivity. We describe current mechanistic understanding of these emergent phenomena with a particular emphasis on the benefits derived from scaling these materials to nanostructured dimensions wherein precise ordering of cations can be obtained and phase relationships can be derived that are entirely inaccessible in the bulk. In particular, structural transformations induced by intercalation are dramatically accelerated due to the shorter diffusion path lengths at nanometer-sized dimensions, which cause a dramatic reduction of kinetic barriers to phase transformations and facilitate interconversion between the different frameworks. We conclude by summarizing numerous technological applications that have become feasible due to recent advances in controlling the structural chemistry and both electronic and structural phase transitions in these versatile frameworks.

A comparative study of the tail ion distribution with reduced Fokker-Planck models

NASA Astrophysics Data System (ADS)

McDevitt, C. J.; Tang, Xian-Zhu; Guo, Zehua; Berk, H. L.

2014-03-01

A series of reduced models are used to study the fast ion tail in the vicinity of a transition layer between plasmas at disparate temperatures and densities, which is typical of the gas and pusher interface in inertial confinement fusion targets. Emphasis is placed on utilizing progressively more comprehensive models in order to identify the essential physics for computing the fast ion tail at energies comparable to the Gamow peak. The resulting fast ion tail distribution is subsequently used to compute the fusion reactivity as a function of collisionality and temperature. While a significant reduction of the fusion reactivity in the hot spot compared to the nominal Maxwellian case is present, this reduction is found to be partially recovered by an increase of the fusion reactivity in the neighboring cold region.

Perturbed Partial Cavity Drag Reduction at High Reynolds Numbers

NASA Astrophysics Data System (ADS)

Makiharju, Simo; Elbing, Brian; Wiggins, Andrew; Dowling, David; Perlin, Marc; Ceccio, Steven

2010-11-01

Ventilated partial cavities were investigated at Reynolds numbers to 80 million. These cavities could be suitable for friction drag reduction on ocean going vessels and thereby lead to environmental and economical benefits. The test model was a 3.05 m wide by 12.9 m long flat plate, with a 0.18 m backward-facing step and a cavity-terminating beach, which had an adjustable slope, tilt and height. The step and beach trapped a ventilated partial cavity over the longitudinal mid-section of the model. Large-scale flow perturbations, mimicking the effect of ambient ocean waves were investigated. For the conditions tested a cavity could be maintained under perturbed flow conditions when the gas flux supplied was greater than the minimum required to maintain a cavity under steady conditions, with larger perturbations requiring more excess gas flux to maintain the cavity. High-speed video was used to observe the unsteady three dimensional cavity closure, the overall cavity shape, and the cavity oscillations. Cavities with friction drag reduction exceeding 95% were attained at optimal conditions. A simplified energy cost-benefit analysis of partial cavity drag reduction was also performed. The results suggest that PCDR could potentially lead to energy savings.

Isostable reduction with applications to time-dependent partial differential equations.

PubMed

Wilson, Dan; Moehlis, Jeff

2016-07-01

Isostables and isostable reduction, analogous to isochrons and phase reduction for oscillatory systems, are useful in the study of nonlinear equations which asymptotically approach a stationary solution. In this work, we present a general method for isostable reduction of partial differential equations, with the potential power to reduce the dimensionality of a nonlinear system from infinity to 1. We illustrate the utility of this reduction by applying it to two different models with biological relevance. In the first example, isostable reduction of the Fokker-Planck equation provides the necessary framework to design a simple control strategy to desynchronize a population of pathologically synchronized oscillatory neurons, as might be relevant to Parkinson's disease. Another example analyzes a nonlinear reaction-diffusion equation with relevance to action potential propagation in a cardiac system.

Minimum fan turbine inlet temperature mode evaluation

NASA Technical Reports Server (NTRS)

Orme, John S.; Nobbs, Steven G.

1995-01-01

Measured reductions in turbine temperature which resulted from the application of the F-15 performance seeking control (PSC) minimum fan turbine inlet temperature (FTIT) mode during the dual-engine test phase is presented as a function of net propulsive force and flight condition. Data were collected at altitudes of 30,000 and 45,000 feet at military and partial afterburning power settings. The FTIT reductions for the supersonic tests are less than at subsonic Mach numbers because of the increased modeling and control complexity. In addition, the propulsion system was designed to be optimized at the mid supersonic Mach number range. Subsonically at military power, FTIT reductions were above 70 R for either the left or right engines, and repeatable for the right engine. At partial afterburner and supersonic conditions, the level of FTIT reductions were at least 25 R and as much as 55 R. Considering that the turbine operates at or very near its temperature limit at these high power settings, these seemingly small temperature reductions may significantly lengthen the life of the turbine. In general, the minimum FTIT mode has performed well, demonstrating significant temperature reductions at military and partial afterburner power. Decreases of over 100 R at cruise flight conditions were identified. Temperature reductions of this magnitude could significantly extend turbine life and reduce replacement costs.

Assessment of female breast dose for thoracic cone-beam CT using MOSFET dosimeters.

PubMed

Sun, Wenzhao; Wang, Bin; Qiu, Bo; Liang, Jian; Xie, Weihao; Deng, Xiaowu; Qi, Zhenyu

2017-03-21

To assess the breast dose during a routine thoracic cone-beam CT (CBCT) check with the efforts to explore the possible dose reduction strategy. Metal oxide semiconductor field-effect transistor (MOSFET) dosimeters were used to measure breast surface doses during a thorax kV CBCT scan in an anthropomorphic phantom. Breast doses for different scanning protocols and breast sizes were compared. Dose reduction was attempted by using partial arc CBCT scan with bowtie filter. The impact of this dose reduction strategy on image registration accuracy was investigated. The average breast surface doses were 20.02 mGy and 11.65 mGy for thoracic CBCT without filtration and with filtration, respectively. This indicates a dose reduction of 41.8% by use of bowtie filter. It was found 220° partial arc scanning significantly reduced the dose to contralateral breast (44.4% lower than ipsilateral breast), while the image registration accuracy was not compromised. Breast dose reduction can be achieved by using ipsilateral 220° partial arc scan with bowtie filter. This strategy also provides sufficient image quality for thorax image registration in daily patient positioning verification.

Whitham modulation theory for the two-dimensional Benjamin-Ono equation.

PubMed

Ablowitz, Mark; Biondini, Gino; Wang, Qiao

2017-09-01

Whitham modulation theory for the two-dimensional Benjamin-Ono (2DBO) equation is presented. A system of five quasilinear first-order partial differential equations is derived. The system describes modulations of the traveling wave solutions of the 2DBO equation. These equations are transformed to a singularity-free hydrodynamic-like system referred to here as the 2DBO-Whitham system. Exact reductions of this system are discussed, the formulation of initial value problems is considered, and the system is used to study the transverse stability of traveling wave solutions of the 2DBO equation.

Higher symmetries and exact solutions of linear and nonlinear Schr{umlt o}dinger equation

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

Fushchych, W.I.; Nikitin, A.G.

1997-11-01

A new approach for the analysis of partial differential equations is developed which is characterized by a simultaneous use of higher and conditional symmetries. Higher symmetries of the Schr{umlt o}dinger equation with an arbitrary potential are investigated. Nonlinear determining equations for potentials are solved using reductions to Weierstrass, Painlev{acute e}, and Riccati forms. Algebraic properties of higher order symmetry operators are analyzed. Combinations of higher and conditional symmetries are used to generate families of exact solutions of linear and nonlinear Schr{umlt o}dinger equations. {copyright} {ital 1997 American Institute of Physics.}

An analysis of commitment strategies in planning: The details

NASA Technical Reports Server (NTRS)

Minton, Steven; Bresina, John; Drummond, Mark; Philips, Andrew B.

1991-01-01

We compare the utility of different commitment strategies in planning. Under a 'least commitment strategy', plans are represented as partial orders and operators are ordered only when interactions are detected. We investigate claims of the inherent advantages of planning with partial orders, as compared to planning with total orders. By focusing our analysis on the issue of operator ordering commitment, we are able to carry out a rigorous comparative analysis of two planners. We show that partial-order planning can be more efficient than total-order planning, but we also show that this is not necessarily so.

Embryonic lethality in mice lacking mismatch-specific thymine DNA glycosylase is partially prevented by DOPS, a precursor of noradrenaline.

PubMed

Saito, Yusuke; Ono, Tetsuya; Takeda, Naoki; Nohmi, Takehiko; Seki, Masayuki; Enomoto, Takemi; Noda, Tetsuo; Uehara, Yoshihiko

2012-01-01

Thymine DNA glycosylase (TDG) is involved in the repair of G:T and G:U mismatches caused by hydrolytic deamination of 5-methylcytosine and cytosine, respectively. Recent studies have shown that TDG not only has G-T/U glycosylase activities but also acts in the maintaining proper epigenetic status. In order to investigate the function of TDG in vivo, mice lacking Tdg, Tdg (-/-), were generated. Tdg mutant mice died in utero by 11.5 days post coitum (dpc), although there were no significant differences in the spontaneous mutant frequencies between wild type and Tdg (-/-) embryos. On the other hand, the levels of noradrenaline in 10.5 dpc whole embryos, which is necessary for normal embryogenesis, were dramatically reduced in Tdg (-/-) embryos. Consequently, we tested the effect of D, L-threo-3, 4-dihydroxyphenylserine (DOPS), a synthetic precursor of noradrenaline, on the survival of the Tdg (-/-) embryos. DOPS was given to pregnant Tdg (+/-) mice from 6.5 dpc through drinking water. Most of the Tdg (-/-) embryos were alive at 11.5 dpc, and they were partially rescued up to 14.5 dpc by the administration of DOPS. In contrast, the administration of L-3, 4-dihydroxyphenylalanine (L-DOPA) had marginal effects on Tdg (-/-) embryonic lethality. No embryo was alive without DOPS beyond 11.5 dpc, suggesting that the lethality in (-/-) embryos is partially due to the reduction of noradrenaline. These results suggest that embryonic lethality in Tdg (-/-) embryos is due, in part, to the reduction of noradrenaline levels.

Development of an Economical Method to Reduce the Extractable Latex Protein Levels in Finished Dipped Rubber Products

PubMed Central

Perera, Ambegoda Liyanage Harini Amalka

2017-01-01

Natural rubber latex (NRL) allergy is caused by the extractable latex proteins in dipped rubber products. It is a major concern for the consumers who are sensitive to the allergenic extractable proteins (EP) in products such as NRL gloves. Objective of this research was to develop an economical method to reduce the EP in finished dipped NRL products. In order to reduce the EP levels, two natural proteases, bromelain from pineapple and papain from papaya, were extracted and partially purified using (NH4)2SO4. According to the newly developed method, different glove samples were treated with a 5% solution of each partially purified enzyme, for 2 hours at 60°C. Residual amounts of in treated samples were quantified using the modified Lowry assay (ASTM D5712-10). Bromelain displayed a 54 (±11)% reduction of the EP from the dipped rubber products, whereas it was 58 (±8)% with papain. These results clearly indicate that the selected natural proteases, bromelain, and papain contribute significantly towards the reduction of the total EP in finished NRL products. Application of bromelain enzyme for the aforementioned purpose has not been reported up to date, whereas papain has been used to treat raw NRL towards reducing the EP. PMID:28706952

76 FR 23334 - Public Land Order No. 7763; Partial Revocation of Public Land Order No. 3708; Alaska

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-26

...] Public Land Order No. 7763; Partial Revocation of Public Land Order No. 3708; Alaska AGENCY: Bureau of Land Management, Interior. ACTION: Public Land Order. SUMMARY: This order revokes a Public Land Order... all forms of appropriation under the public land laws, including the mining laws, for the protection...

Spatial complexity of solutions of higher order partial differential equations

NASA Astrophysics Data System (ADS)

Kukavica, Igor

2004-03-01

We address spatial oscillation properties of solutions of higher order parabolic partial differential equations. In the case of the Kuramoto-Sivashinsky equation ut + uxxxx + uxx + u ux = 0, we prove that for solutions u on the global attractor, the quantity card {x epsi [0, L]:u(x, t) = lgr}, where L > 0 is the spatial period, can be bounded by a polynomial function of L for all \\lambda\\in{\\Bbb R} . A similar property is proven for a general higher order partial differential equation u_t+(-1)^{s}\\partial_x^{2s}u+ \\sum_{k=0}^{2s-1}v_k(x,t)\\partial_x^k u =0 .

Partial Data Traces: Efficient Generation and Representation

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

Mueller, F; De Supinski, B R; McKee, S A

2001-08-20

Binary manipulation techniques are increasing in popularity. They support program transformations tailored toward certain program inputs, and these transformations have been shown to yield performance gains beyond the scope of static code optimizations without profile-directed feedback. They even deliver moderate gains in the presence of profile-guided optimizations. In addition, transformations can be performed on the entire executable, including library routines. This work focuses on program instrumentation, yet another application of binary manipulation. This paper reports preliminary results on generating partial data traces through dynamic binary rewriting. The contributions are threefold. First, a portable method for extracting precise data traces formore » partial executions of arbitrary applications is developed. Second, a set of hierarchical structures for compactly representing these accesses is developed. Third, an efficient online algorithm to detect regular accesses is introduced. The authors utilize dynamic binary rewriting to selectively collect partial address traces of regions within a program. This allows partial tracing of hot paths for only a short time during program execution in contrast to static rewriting techniques that lack hot path detection and also lack facilities to limit the duration of data collection. Preliminary results show reductions of three orders of a magnitude of inline instrumentation over a dual process approach involving context switching. They also report constant size representations for regular access patters in nested loops. These efforts are part of a larger project to counter the increasing gap between processor and main memory speeds by means of software optimization and hardware enhancements.« less

20 CFR 404.440 - Partial monthly benefits; pro-rated share of partial payment exceeds the benefit before deduction...

Code of Federal Regulations, 2010 CFR

2010-04-01

... imposed; and the balance of the partial benefit is paid to the other. If three or more beneficiaries are... rate (before reduction for the family maximum). If the excess amount involved at any point totals less...

78 FR 28894 - Public Land Order No. 7814; Partial Revocation of Bureau of Reclamation Order Dated July 11, 1955...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-16

... DEPARTMENT OF THE INTERIOR Bureau of Land Management [NEW 149341 and NEW 179095] Public Land Order No. 7814; Partial Revocation of Bureau of Reclamation Order Dated July 11, 1955, and Transfer of... Land Order. SUMMARY: This order revokes in-part a withdrawal created by a Bureau of Reclamation Order...

Planning actions in robot automated operations

NASA Technical Reports Server (NTRS)

Das, A.

1988-01-01

Action planning in robot automated operations requires intelligent task level programming. Invoking intelligence necessiates a typical blackboard based architecture, where, a plan is a vector between the start frame and the goal frame. This vector is composed of partially ordered bases. A partial ordering of bases presents good and bad sides in action planning. Partial ordering demands the use of a temporal data base management system.

Photosensitized Reduction of Carbon Dioxide in Solution Using Noble-Metal Clusters for Electron Transfer

NASA Astrophysics Data System (ADS)

Toshima, Naoki; Yamaji, Yumi; Teranishi, Toshiharu; Yonezawa, Tetsu

1995-03-01

Carbon dioxide was reduced to methane by visible-light irradiation of a solution composed of tris(bipyridine)ruthenium(III) as photosensitizer, ethylenediaminetetraacetic acid disodium salt as sacrificial reagent, methyl viologen as electron relay, and a colloidal dispersion of polymer-protected noble-metal clusters, prepared by alcohol-reduction, as catalyst. Among the noble-metal clusters examined, Pt clusters showed the highest activity for the formation of methane as well as hydrogen. In order to improve the activity, oxidized clusters and bimetallic clusters were also applied. For example, the CH4 yield in 3-h irradiation increased from 51 x 10-3 μmol with unoxidized Pt clusters to 72 x 10-3 μmol with partially oxidized ones. In the case of Pt/Ru bimetalic systems, the improvement of the catalytic activity by air treatment was much greater than in case of monometallic clusters.

Assessment of female breast dose for thoracic cone-beam CT using MOSFET dosimeters

PubMed Central

Qiu, Bo; Liang, Jian; Xie, Weihao; Deng, Xiaowu; Qi, Zhenyu

2017-01-01

Objective: To assess the breast dose during a routine thoracic cone-beam CT (CBCT) check with the efforts to explore the possible dose reduction strategy. Materials and Methods: Metal oxide semiconductor field-effect transistor (MOSFET) dosimeters were used to measure breast surface doses during a thorax kV CBCT scan in an anthropomorphic phantom. Breast doses for different scanning protocols and breast sizes were compared. Dose reduction was attempted by using partial arc CBCT scan with bowtie filter. The impact of this dose reduction strategy on image registration accuracy was investigated. Results: The average breast surface doses were 20.02 mGy and 11.65 mGy for thoracic CBCT without filtration and with filtration, respectively. This indicates a dose reduction of 41.8% by use of bowtie filter. It was found 220° partial arc scanning significantly reduced the dose to contralateral breast (44.4% lower than ipsilateral breast), while the image registration accuracy was not compromised. Conclusions: Breast dose reduction can be achieved by using ipsilateral 220° partial arc scan with bowtie filter. This strategy also provides sufficient image quality for thorax image registration in daily patient positioning verification. PMID:28423624

"Snowflake" divertor configuration in NSTX

NASA Astrophysics Data System (ADS)

Soukhanovskii, V. A.; Ahn, J.-W.; Bell, R. E.; Gates, D. A.; Gerhardt, S.; Kaita, R.; Kolemen, E.; Kugel, H. W.; Leblanc, B. P.; Maingi, R.; Maqueda, R.; McLean, A.; Menard, J. E.; Mueller, D. M.; Paul, S. F.; Raman, R.; Roquemore, A. L.; Ryutov, D. D.; Scott, H. A.

2011-08-01

Steady-state handling of divertor heat flux is a critical issue for present and future conventional and spherical tokamaks with compact high power density divertors. A novel "snowflake" divertor (SFD) configuration that takes advantage of magnetic properties of a second-order poloidal null has been predicted to have a larger plasma-wetted area and a larger divertor volume, in comparison with a standard first-order poloidal X-point divertor configuration. The SFD was obtained in 0.8 MA, 4-6 MW NBI-heated H-mode discharges in NSTX using two divertor magnetic coils. The SFD led to a partial detachment of the outer strike point even in low-collisionality scrape-off layer plasma obtained with lithium coatings in NSTX. Significant divertor peak heat flux reduction and impurity screening have been achieved simultaneously with good core confinement and MHD properties.

[Bio-electrochemical effect on hydrogenotrophic sulfate reduction stimulated by electrical field in the presence of H2 under atmospheric pressure].

PubMed

Xu, Hui-Wei; Zhang, Xu; Yang, Shan-Shan; Li, Guang-He

2009-07-15

Microbial sulfate reduction rate is limited with H2 as electron donor. In order to improve hydrogenotrophic sulfate reduction under normal atmospheric H2 pressure, a bio-electrochemical system with direct current was designed and performed in this study. Results indicates that sulfate reduction rate (SRR) increases with the augment of current intensity under lower current intensity (I < or = 1.50 mA). When optimum current intensity of 1.50 mA is applied, the SRR is 1.7 to 2.1 times higher than that of the control reactor. The synergistic effect of electrochemistry and microbiology on sulfate reduction varies at different current intensity. Under the condition of I < or = 1.50 mA, the most probable mechanism of SRR increase is that electric or magnetic field stimulates the proliferation of sulfate-reducing bacteria (SRB) and the activity of the enzymes. When I is higher than 1.50 mA, the activity of SRB is inhibited, resulting in lower reduction rate compared with that at lower current. If controlling the cathode potential lower than -0.69 V and H2 partial pressure 1.01 x 10(5) Pa, electro-catalytic sulfate reduction process takes place with H2 as reductant in this bio-electrochemical system. However, the overall reduction rate is still lower than that when I = 1.50 mA is applied, and additionally the energy consumption is much higher. Therefore, electric field of low intensity can enhance hydrogenotrophic sulfate reduction in the presence of H2 under atmospheric pressure.

[Effectiveness of partial and complete instrumental masking in chronic tinnitus. Studies with reference to retraining therapy].

PubMed

von Wedel, H; von Wedel, U C; Streppel, M; Walger, M

1997-09-01

Jastreboff und Hazell [9] developed a neurophysiological approach to tinnitus perception, including the important role of the central nervous system in the maintenance and intrusiveness of tinnitus. They introduced tinnitus-retraining therapy, consisting of four different strategies: (1) directive and person-centered counseling; (2) hearing aids and/or noise generators and/or environmental sounds; (3) psychological therapy; (4) adjacent therapies. Tinnitus should not be masked as with a tinnitus-masker, but must be able to be heard in addition to the noise! A noise generator or hearing aid should be worn at least 6-8 h per day over a period of up to 18 months. In additions several clinical visits are required in order to reinforce the counseling. The actual results show complete tinnitus remission for about 20-30% and partial remission for 50-60% of the patients [6]. We report on a retrospective study in patients wearing hearing aids or tinnitus-maskers over a period of 3 years. We compared the results of patients using partial tinnitus masking to those using complete masking. The tinnitus-related and general psychological complaints were acquired by the 52-item tinnitus questionnaire developed by Hallam et al. [4] and modified by Goebel and Hiller [3]. To describe the dimensions of tinnitus-related distress the scales are labelled emotional distress, cognitive distress, emotional and cognitive distress, intrusiveness, auditory perceptual difficulties, sleep disturbance and somatic complaints. Positive changes for the global tinnitus questionnaire score of more than 10 points are significant in the dimensions of tinnitus-related distress and are described as partial tinnitus-reduction. The group with partial masking effects can be compared to those performing retraining therapy to day because directive and personal centered counseling were integrated for all patients. Patients reporting partial masking effects through their aids (hearing aid or noise generator) showed more effective treatment results (reduced or disappeared tinnitus) than those using complete masking effects (P < 0.05). The reported results are improved by current investigations in Germany showing about 20-30% tinnitus remission and 50-60% significant reduction after 1 year of treatment [1]. Further scientific investigations must be carried out to evaluate the appropriateness and effectiveness of the retraining therapy and with regard to unique quality standards.

Low temperature time resolved photoluminescence in ordered and disordered Cu2ZnSnS4 single crystals

NASA Astrophysics Data System (ADS)

Raadik, Taavi; Krustok, Jüri; Kauk-Kuusik, M.; Timmo, K.; Grossberg, M.; Ernits, K.; Bleuse, J.

2017-03-01

In this work we performed time-resolved micro-photoluminescence (TRPL) studies of Cu2ZnSnS4 (CZTS) single crystals grown in molten KI salt. The order/disorder degree of CZTS was varied by the thermal post treatment temperature. Photoluminescence spectra measured at T=8 K showed an asymmetric band with a peak position of 1.33 eV and 1.27 eV for partially ordered and disordered structures, respectively. Thermal activation energies were found to be ET (PO) =65±9 meV for partially ordered and ET (PD) =27±4 meV for partially disordered. These low activation energy values indicating to the defect cluster recombination model for both partially ordered and disordered structures. TRPL was measured for both crystals and their decay curves were fitted with a stretched exponential function, in order to describe the charge carriers' recombination dynamics at low temperature.

Construction and accuracy of partial differential equation approximations to the chemical master equation.

PubMed

Grima, Ramon

2011-11-01

The mesoscopic description of chemical kinetics, the chemical master equation, can be exactly solved in only a few simple cases. The analytical intractability stems from the discrete character of the equation, and hence considerable effort has been invested in the development of Fokker-Planck equations, second-order partial differential equation approximations to the master equation. We here consider two different types of higher-order partial differential approximations, one derived from the system-size expansion and the other from the Kramers-Moyal expansion, and derive the accuracy of their predictions for chemical reactive networks composed of arbitrary numbers of unimolecular and bimolecular reactions. In particular, we show that the partial differential equation approximation of order Q from the Kramers-Moyal expansion leads to estimates of the mean number of molecules accurate to order Ω(-(2Q-3)/2), of the variance of the fluctuations in the number of molecules accurate to order Ω(-(2Q-5)/2), and of skewness accurate to order Ω(-(Q-2)). We also show that for large Q, the accuracy in the estimates can be matched only by a partial differential equation approximation from the system-size expansion of approximate order 2Q. Hence, we conclude that partial differential approximations based on the Kramers-Moyal expansion generally lead to considerably more accurate estimates in the mean, variance, and skewness than approximations of the same order derived from the system-size expansion.

Efficient model reduction of parametrized systems by matrix discrete empirical interpolation

NASA Astrophysics Data System (ADS)

Negri, Federico; Manzoni, Andrea; Amsallem, David

2015-12-01

In this work, we apply a Matrix version of the so-called Discrete Empirical Interpolation (MDEIM) for the efficient reduction of nonaffine parametrized systems arising from the discretization of linear partial differential equations. Dealing with affinely parametrized operators is crucial in order to enhance the online solution of reduced-order models (ROMs). However, in many cases such an affine decomposition is not readily available, and must be recovered through (often) intrusive procedures, such as the empirical interpolation method (EIM) and its discrete variant DEIM. In this paper we show that MDEIM represents a very efficient approach to deal with complex physical and geometrical parametrizations in a non-intrusive, efficient and purely algebraic way. We propose different strategies to combine MDEIM with a state approximation resulting either from a reduced basis greedy approach or Proper Orthogonal Decomposition. A posteriori error estimates accounting for the MDEIM error are also developed in the case of parametrized elliptic and parabolic equations. Finally, the capability of MDEIM to generate accurate and efficient ROMs is demonstrated on the solution of two computationally-intensive classes of problems occurring in engineering contexts, namely PDE-constrained shape optimization and parametrized coupled problems.

A multi-level solution algorithm for steady-state Markov chains

NASA Technical Reports Server (NTRS)

Horton, Graham; Leutenegger, Scott T.

1993-01-01

A new iterative algorithm, the multi-level algorithm, for the numerical solution of steady state Markov chains is presented. The method utilizes a set of recursively coarsened representations of the original system to achieve accelerated convergence. It is motivated by multigrid methods, which are widely used for fast solution of partial differential equations. Initial results of numerical experiments are reported, showing significant reductions in computation time, often an order of magnitude or more, relative to the Gauss-Seidel and optimal SOR algorithms for a variety of test problems. The multi-level method is compared and contrasted with the iterative aggregation-disaggregation algorithm of Takahashi.

Algorithmic framework for group analysis of differential equations and its application to generalized Zakharov-Kuznetsov equations

NASA Astrophysics Data System (ADS)

Huang, Ding-jiang; Ivanova, Nataliya M.

2016-02-01

In this paper, we explain in more details the modern treatment of the problem of group classification of (systems of) partial differential equations (PDEs) from the algorithmic point of view. More precisely, we revise the classical Lie algorithm of construction of symmetries of differential equations, describe the group classification algorithm and discuss the process of reduction of (systems of) PDEs to (systems of) equations with smaller number of independent variables in order to construct invariant solutions. The group classification algorithm and reduction process are illustrated by the example of the generalized Zakharov-Kuznetsov (GZK) equations of form ut +(F (u)) xxx +(G (u)) xyy +(H (u)) x = 0. As a result, a complete group classification of the GZK equations is performed and a number of new interesting nonlinear invariant models which have non-trivial invariance algebras are obtained. Lie symmetry reductions and exact solutions for two important invariant models, i.e., the classical and modified Zakharov-Kuznetsov equations, are constructed. The algorithmic framework for group analysis of differential equations presented in this paper can also be applied to other nonlinear PDEs.

Doppler Imaging with FUSE: The Partially Eclipsing Binary VW Cep

NASA Technical Reports Server (NTRS)

Sonneborn, George (Technical Monitor); Brickhouse, Nancy

2003-01-01

This report covers the FUSE Guest Observer program. This project involves the study of emission line profiles for the partially eclipsing, rapidly rotating binary system VW Cep. Active regions on the surface of the star(s) produce observable line shifts as the stars move with respect to the observer. By studying the time-dependence of the line profile changes and centroid shifts, one can determine the location of the activity. FUSE spectra were obtained by the P.I. 27 Sept 2002 and data reduction is in progress. Since we are interested in line profile analysis, we are now investigating the wavelength scale calibration in some detail. We have also obtained and are analyzing Chandra data in order to compare the X-ray velocities with the FUV velocities. A complementary project comparing X-ray and Far UltraViolet (FUV) emission for the similar system 44i Boo is also underway. Postdoctoral fellow Ronnie Hoogerwerf has joined the investigation team and will perform the data analysis, once the calibration is optimized.

Reduction of deviation angle during occlusion therapy: in partially accommodative esotropia with moderate amblyopia.

PubMed

Chun, Bo Young; Kwon, Soon Jae; Chae, Sun Hwa; Kwon, Jung Yoon

2007-09-01

To evaluate changes in ocular alignment in partially accommodative esotropic children age ranged from 3 to 8 years during occlusion therapy for amblyopia. Angle measurements of twenty-two partially accommodative esotropic patients with moderate amblyopia were evaluated before and at 2 years after occlusion therapy. Mean deviation angle with glasses at the start of occlusion treatment was 19.45+/-5.97 PD and decreased to 12.14+/-12.96 PD at 2 years after occlusion therapy (p<0.01). After occlusion therapy, 9 (41%) cases were indications of surgery for residual deviation but if we had planned surgery before occlusion treatment, 18 (82%) of patients would have had surgery. There was a statistical relationship between increase of visual acuity ratio and decrease of deviation angle (r=-0.479, p=0.024). There was a significant reduction of deviation angle of partially accommodative esotropic patients at 2 years after occlusion therapy. Our results suggest that occlusion therapy has an influence on ocular alignment in partially accommodative esotropic patients with amblyopia.

Genomic Characterization of Methanomicrobiales Reveals Three Classes of Methanogens

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

Anderson, Iain; Ulrich, Luke E.; Lupa, Boguslaw

2009-05-01

Methanomicrobiales is the least studied order of methanogens. While these organisms appear to be more closely related to the Methanosarcinales in ribosomal-based phylogenetic analyses, they are metabolically more similar to Class I methanogens. In order to improve our understanding of this lineage, we have completely sequenced the genomes of two members of this order, Methanocorpusculum labreanum Z and Methanoculleus marisnigri JR1, and compared them with the genome of a third, Methanospirillum hungatei JF-1. Similar to Class I methanogens, Methanomicrobiales use a partial reductive citric acid cycle for 2-oxoglutarate biosynthesis, and they have the Eha energy-converting hydrogenase. In common with Methanosarcinales,more » Methanomicrobiales possess the Ech hydrogenase and at least some of them may couple formylmethanofuran formation and heterodisulfide reduction to transmembrane ion gradients. Uniquely, M. labreanum and M. hungatei contain hydrogenases similar to the Pyrococcus furiosus Mbh hydrogenase, and all three Methanomicrobiales have anti-sigma factor and anti-anti-sigma factor regulatory proteins not found in other methanogens. Phylogenetic analysis based on seven core proteins of methanogenesis and cofactor biosynthesis places the Methanomicrobiales equidistant from Class I methanogens and Methanosarcinales. Our results indicate that Methanomicrobiales, rather than being similar to Class I methanogens or Methanomicrobiales, share some features of both and have some unique properties. We find that there are three distinct classes of methanogens: the Class I methanogens, the Methanomicrobiales (Class II), and the Methanosarcinales (Class III).« less

75 FR 59743 - Public Land Order No. 7750; Partial Revocation of Secretarial Order dated January 20, 1910; Oregon

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-28

... partially revokes a Secretarial Order dated January 20, 1910, insofar as it affects approximately 9,001.84... is no longer needed for the purpose for which it was withdrawn. DATES: Effective Date: September 28..., it is ordered as follows: The Secretarial Order dated January 20, 1910, which withdrew land on behalf...

Is scale-invariance in gauge-Yukawa systems compatible with the graviton?

NASA Astrophysics Data System (ADS)

Christiansen, Nicolai; Eichhorn, Astrid; Held, Aaron

2017-10-01

We explore whether perturbative interacting fixed points in matter systems can persist under the impact of quantum gravity. We first focus on semisimple gauge theories and show that the leading order gravity contribution evaluated within the functional Renormalization Group framework preserves the perturbative fixed-point structure in these models discovered in [J. K. Esbensen, T. A. Ryttov, and F. Sannino, Phys. Rev. D 93, 045009 (2016)., 10.1103/PhysRevD.93.045009]. We highlight that the quantum-gravity contribution alters the scaling dimension of the gauge coupling, such that the system exhibits an effective dimensional reduction. We secondly explore the effect of metric fluctuations on asymptotically safe gauge-Yukawa systems which feature an asymptotically safe fixed point [D. F. Litim and F. Sannino, J. High Energy Phys. 12 (2014) 178., 10.1007/JHEP12(2014)178]. The same effective dimensional reduction that takes effect in pure gauge theories also impacts gauge-Yukawa systems. There, it appears to lead to a split of the degenerate free fixed point into an interacting infrared attractive fixed point and a partially ultraviolet attractive free fixed point. The quantum-gravity induced infrared fixed point moves towards the asymptotically safe fixed point of the matter system, and annihilates it at a critical value of the gravity coupling. Even after that fixed-point annihilation, graviton effects leave behind new partially interacting fixed points for the matter sector.

Coalescence with Background and Balancing Selection in Systems with Bi- and Uniparental Reproduction: Contrasting Partial Asexuality and Selfing

PubMed Central

Agrawal, Aneil F.; Hartfield, Matthew

2016-01-01

Uniparental reproduction in diploids, via asexual reproduction or selfing, reduces the independence with which separate loci are transmitted across generations. This is expected to increase the extent to which a neutral marker is affected by selection elsewhere in the genome. Such effects have previously been quantified in coalescent models involving selfing. Here we examine the effects of background selection and balancing selection in diploids capable of both sexual and asexual reproduction (i.e., partial asexuality). We find that the effect of background selection on reducing coalescent time (and effective population size) can be orders of magnitude greater when rates of sex are low than when sex is common. This is because asexuality enhances the effects of background selection through both a recombination effect and a segregation effect. We show that there are several reasons that the strength of background selection differs between systems with partial asexuality and those with comparable levels of uniparental reproduction via selfing. Expectations for reductions in Ne via background selection have been verified using stochastic simulations. In contrast to background selection, balancing selection increases the coalescence time for a linked neutral site. With partial asexuality, the effect of balancing selection is somewhat dependent upon the mode of selection (e.g., heterozygote advantage vs. negative frequency-dependent selection) in a manner that does not apply to selfing. This is because the frequency of heterozygotes, which are required for recombination onto alternative genetic backgrounds, is more dependent on the pattern of selection with partial asexuality than with selfing. PMID:26584901

Coalescence with Background and Balancing Selection in Systems with Bi- and Uniparental Reproduction: Contrasting Partial Asexuality and Selfing.

PubMed

Agrawal, Aneil F; Hartfield, Matthew

2016-01-01

Uniparental reproduction in diploids, via asexual reproduction or selfing, reduces the independence with which separate loci are transmitted across generations. This is expected to increase the extent to which a neutral marker is affected by selection elsewhere in the genome. Such effects have previously been quantified in coalescent models involving selfing. Here we examine the effects of background selection and balancing selection in diploids capable of both sexual and asexual reproduction (i.e., partial asexuality). We find that the effect of background selection on reducing coalescent time (and effective population size) can be orders of magnitude greater when rates of sex are low than when sex is common. This is because asexuality enhances the effects of background selection through both a recombination effect and a segregation effect. We show that there are several reasons that the strength of background selection differs between systems with partial asexuality and those with comparable levels of uniparental reproduction via selfing. Expectations for reductions in Ne via background selection have been verified using stochastic simulations. In contrast to background selection, balancing selection increases the coalescence time for a linked neutral site. With partial asexuality, the effect of balancing selection is somewhat dependent upon the mode of selection (e.g., heterozygote advantage vs. negative frequency-dependent selection) in a manner that does not apply to selfing. This is because the frequency of heterozygotes, which are required for recombination onto alternative genetic backgrounds, is more dependent on the pattern of selection with partial asexuality than with selfing. Copyright © 2016 by the Genetics Society of America.

Relationship between neurotoxic kynurenine metabolites and reductions in right medial prefrontal cortical thickness in major depressive disorder.

PubMed

Meier, Timothy B; Drevets, Wayne C; Wurfel, Brent E; Ford, Bart N; Morris, Harvey M; Victor, Teresa A; Bodurka, Jerzy; Teague, T Kent; Dantzer, Robert; Savitz, Jonathan

2016-03-01

Reductions in gray matter volume of the medial prefrontal cortex (mPFC), especially the rostral and subgenual anterior cingulate cortex (rACC, sgACC) are a widely reported finding in major depressive disorder (MDD). Inflammatory mediators, which are elevated in a subgroup of patients with MDD, activate the kynurenine metabolic pathway and increase production of neuroactive metabolites such as kynurenic acid (KynA), 3-hydroxykynurenine (3HK) and quinolinic acid (QA) which influence neuroplasticity. It is not known whether the alterations in brain structure and function observed in major depressive disorders are due to the direct effect of inflammatory mediators or the effects of neurotoxic kynurenine metabolites. Here, using partial posterior predictive distribution mediation analysis, we tested whether the serum concentrations of kynurenine pathway metabolites mediated reductions in cortical thickness in mPFC regions in MDD. Further, we tested whether any association between C-reactive protein (CRP) and cortical thickness would be mediated by kynurenine pathway metabolites. Seventy-three unmedicated subjects who met DSM-IV-TR criteria for MDD and 91 healthy controls (HC) completed MRI scanning using a pulse sequence optimized for tissue contrast resolution. Automated cortical parcellation was performed using the PALS-B12 Brodmann area atlas as implemented in FreeSurfer in order to compare the cortical thickness and cortical area of six PFC regions: Brodmann areas (BA) 9, 10, 11, 24, 25, and 32. Serum concentrations of kynurenine pathway metabolites were determined by high performance liquid chromatography (HPLC) with tandem mass spectrometry (MS/MS) detection, while high-sensitivity CRP concentration was measured immunoturbidimetrically. Compared with HCs, the MDD group showed a reduction in cortical thickness of the right BA24 (p<0.01) and BA32 (p<0.05) regions and MDD patients with a greater number of depressive episodes displayed thinner cortex in BA32 (p<0.05). Consistent with our previous findings in an overlapping sample, the KynA/3HK ratio and the log KynA/QA were reduced in the MDD group relative to the HC group (p's<0.05) and symptoms of anhedonia were negatively correlated with log KynA/QA in the MDD group (p<0.05). Both KynA/3HK and log KynA/QA at least partially mediated the relationship between diagnosis and cortical thickness of right BA32 (p's<0.05). CRP was inversely associated with BA32 thickness (p<0.01) and KynA/3HK partially mediated the relationship between CRP and the thickness of right BA32 (p<0.05). The results raise the possibility that the relative imbalance between KynA and neurotoxic kynurenine metabolites may partially explain the reductions in mPFC thickness observed in MDD, and further that these changes are more strongly linked to the putative effects of neuroactive kynurenine metabolites than those of inflammatory mediators. Copyright © 2015 Elsevier Inc. All rights reserved.

Using the time-to-event continual reassessment method in the presence of partial orders

PubMed Central

Wages, Nolan A.; Conaway, Mark R.; O'Quigley, John

2012-01-01

The time-to-event continual reassessment method (TITE-CRM) was proposed to handle the problem of long trial duration in Phase 1 trials as a result of late-onset toxicities. Here, we implement the TITE-CRM in dose–finding trials of combinations of agents. When studying multiple agents, monotonicity of the dose-toxicity curve is not clearly defined. Therefore, the toxicity probabilities follow a partial order, meaning that there are pairs of treatments for which the ordering of the toxicity probabilities is not known at the start of the trial. A CRM design for partially ordered trials (PO-CRM) was recently proposed. Simulation studies show that extending the TITE-CRM to the partial order setting produces results similar to those of the PO-CRM in terms of maximum tolerated dose recommendation yet reduces the duration of the trial. PMID:22806898

Structural, textural and sensory impact of sodium reduction on long fermented pizza.

PubMed

Bernklau, Isabelle; Neußer, Christian; Moroni, Alice V; Gysler, Christof; Spagnolello, Alessandro; Chung, Wookyung; Jekle, Mario; Becker, Thomas

2017-11-01

The aim of this study was to elucidate the microstructural, textural, and sensory impact of sodium reduction and its partial replacement by potassium chloride in pizza dough and crusts prepared by a traditional long fermentation process. For the first time, macrostructural changes in texture were elucidated and quantified by a novel protein network analysis. The fermentation process exerted a strengthening effect in the doughs, allowing to reduce sodium up to 25% without any negative impact on texture. Sodium reduction by 15% did not cause any significant textural changes in pizza crusts and partial replacement by KCl resulted in a strengthened dough and firmer pizza crust. The use of toppings masked the effect of lowering the sodium content, allowing to increase the reduction level from 15% to 35%. A reduction of NaCl by 25% with an addition of KCl achieved high acceptance in the sensory evaluation. Copyright © 2017 Elsevier Ltd. All rights reserved.

Numerical simulation of Forchheimer flow to a partially penetrating well with a mixed-type boundary condition

NASA Astrophysics Data System (ADS)

Mathias, Simon A.; Wen, Zhang

2015-05-01

This article presents a numerical study to investigate the combined role of partial well penetration (PWP) and non-Darcy effects concerning the performance of groundwater production wells. A finite difference model is developed in MATLAB to solve the two-dimensional mixed-type boundary value problem associated with flow to a partially penetrating well within a cylindrical confined aquifer. Non-Darcy effects are incorporated using the Forchheimer equation. The model is verified by comparison to results from existing semi-analytical solutions concerning the same problem but assuming Darcy's law. A sensitivity analysis is presented to explore the problem of concern. For constant pressure production, Non-Darcy effects lead to a reduction in production rate, as compared to an equivalent problem solved using Darcy's law. For fully penetrating wells, this reduction in production rate becomes less significant with time. However, for partially penetrating wells, the reduction in production rate persists for much larger times. For constant production rate scenarios, the combined effect of PWP and non-Darcy flow takes the form of a constant additional drawdown term. An approximate solution for this loss term is obtained by performing linear regression on the modeling results.

Partial Agenesis and Hypoplasia of the Corpus Callosum in Idiopathic Autism

PubMed Central

Wegiel, Jarek; Flory, Michael; Kaczmarski, Wojciech; Brown, W. Ted; Chadman, Kathryn; Wisniewski, Thomas; Nowicki, Krzysztof; Kuchna, Izabela; Ma, Shuang Yong; Wegiel, Jerzy

2017-01-01

Abstract To test the hypothesis that developmental anomalies of the corpus callosum (CC), contribute to the pathogenesis of autism, we characterized the type, topography, and severity of CC pathology corresponding to reduced CC areas that are detected by magnetic resonance imaging in the brains of 11 individuals with autism and 11 controls. In the brains of 3 autistic subjects, partial CC agenesis resulted in complete or partial lack of interhemispheric axonal connections in CC segments III–V. In these cases, a combination of focal agenesis and uniform axonal deficit caused reduction of CC areas by 37%, of axon numbers by 62%, and of the numerical density of axons by 39%. In the CC of 8 autistic subjects without agenesis, there was an 18% deficit of the midsagittal CC area, 48.4% deficit of axon numbers, and 37% reduction of the numerical density of axons. The significantly thinner CC, reduced CC area, and uniform axonal deficit in all autistic subjects were classified as CC hypoplasia. Thus, the byproduct of partial CC agenesis and hypoplasia is reduction of axonal connections between cortical areas known to be involved in behavioral alterations observed in people with autism. PMID:28395085

ppcor: An R Package for a Fast Calculation to Semi-partial Correlation Coefficients.

PubMed

Kim, Seongho

2015-11-01

Lack of a general matrix formula hampers implementation of the semi-partial correlation, also known as part correlation, to the higher-order coefficient. This is because the higher-order semi-partial correlation calculation using a recursive formula requires an enormous number of recursive calculations to obtain the correlation coefficients. To resolve this difficulty, we derive a general matrix formula of the semi-partial correlation for fast computation. The semi-partial correlations are then implemented on an R package ppcor along with the partial correlation. Owing to the general matrix formulas, users can readily calculate the coefficients of both partial and semi-partial correlations without computational burden. The package ppcor further provides users with the level of the statistical significance with its test statistic.

Partial Cavity Flows at High Reynolds Numbers

NASA Astrophysics Data System (ADS)

Makiharju, Simo; Elbing, Brian; Wiggins, Andrew; Dowling, David; Perlin, Marc; Ceccio, Steven

2009-11-01

Partial cavity flows created for friction drag reduction were examined on a large-scale. Partial cavities were investigated at Reynolds numbers up to 120 million, and stable cavities with frictional drag reduction of more than 95% were attained at optimal conditions. The model used was a 3 m wide and 12 m long flat plate with a plenum on the bottom. To create the partial cavity, air was injected at the base of an 18 cm backwards-facing step 2.1 m from the leading edge. The geometry at the cavity closure was varied for different flow speeds to optimize the closure of the cavity. Cavity gas flux, thickness, frictional loads, and cavity pressures were measured over a range of flow speeds and air injection fluxes. High-speed video was used extensively to investigate the unsteady three dimensional cavity closure, the overall cavity shape and oscillations.

77 FR 53226 - Public Land Order No. 7793; Partial Revocation of Public Land Order No. 1535; South Dakota

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-31

... DEPARTMENT OF THE INTERIOR Bureau of Land Management [SDM 013790] Public Land Order No. 7793; Partial Revocation of Public Land Order No. 1535; South Dakota Correction In notice document 2012-18885 appearing on page 46112 of the issue of Thursday, August 2, 2012 make the following correction: On page...

Dynamics of weakly inhomogeneous oscillator populations: perturbation theory on top of Watanabe-Strogatz integrability

NASA Astrophysics Data System (ADS)

Vlasov, Vladimir; Rosenblum, Michael; Pikovsky, Arkady

2016-08-01

As has been shown by Watanabe and Strogatz (WS) (1993 Phys. Rev. Lett. 70 2391), a population of identical phase oscillators, sine-coupled to a common field, is a partially integrable system: for any ensemble size its dynamics reduce to equations for three collective variables. Here we develop a perturbation approach for weakly nonidentical ensembles. We calculate corrections to the WS dynamics for two types of perturbations: those due to a distribution of natural frequencies and of forcing terms, and those due to small white noise. We demonstrate that in both cases, the complex mean field for which the dynamical equations are written is close to the Kuramoto order parameter, up to the leading order in the perturbation. This supports the validity of the dynamical reduction suggested by Ott and Antonsen (2008 Chaos 18 037113) for weakly inhomogeneous populations.

77 FR 58868 - Public Land Order No. 7798; Partial Modification of Power Site Classification No. 126; Washington

Federal Register 2010, 2011, 2012, 2013, 2014

2012-09-24

...; WAOR-19641] Public Land Order No. 7798; Partial Modification of Power Site Classification No. 126... partially modifies a withdrawal which established Power Site Classification No. 126, insofar as it affects... under Power Site Classification No. 126 for water power purposes will not be injured by U.S. Forest...

Reduced-order dynamic output feedback control of uncertain discrete-time Markov jump linear systems

NASA Astrophysics Data System (ADS)

Morais, Cecília F.; Braga, Márcio F.; Oliveira, Ricardo C. L. F.; Peres, Pedro L. D.

2017-11-01

This paper deals with the problem of designing reduced-order robust dynamic output feedback controllers for discrete-time Markov jump linear systems (MJLS) with polytopic state space matrices and uncertain transition probabilities. Starting from a full order, mode-dependent and polynomially parameter-dependent dynamic output feedback controller, sufficient linear matrix inequality based conditions are provided for the existence of a robust reduced-order dynamic output feedback stabilising controller with complete, partial or none mode dependency assuring an upper bound to the ? or the ? norm of the closed-loop system. The main advantage of the proposed method when compared to the existing approaches is the fact that the dynamic controllers are exclusively expressed in terms of the decision variables of the problem. In other words, the matrices that define the controller realisation do not depend explicitly on the state space matrices associated with the modes of the MJLS. As a consequence, the method is specially suitable to handle order reduction or cluster availability constraints in the context of ? or ? dynamic output feedback control of discrete-time MJLS. Additionally, as illustrated by means of numerical examples, the proposed approach can provide less conservative results than other conditions in the literature.

Experimental Studies on Wave Interactions of Partially Perforated Wall under Obliquely Incident Waves

PubMed Central

Lee, Jong-In; Kim, Young-Taek; Shin, Sungwon

2014-01-01

This study presents wave height distribution in terms of stem wave evolution phenomena on partially perforated wall structures through three-dimensional laboratory experiments. The plain and partially perforated walls were tested to understand their effects on the stem wave evolution under the monochromatic and random wave cases with the various wave conditions, incident angle (from 10 to 40 degrees), and configurations of front and side walls. The partially perforated wall reduced the relative wave heights more effectively compared to the plain wall structure. Partially perforated walls with side walls showed a better performance in terms of wave height reduction compared to the structure without the side wall. Moreover, the relative wave heights along the wall were relatively small when the relative chamber width is large, within the range of the chamber width in this study. The wave spectra showed a frequency dependency of the wave energy dissipation. In most cases, the existence of side wall is a more important factor than the porosity of the front wall in terms of the wave height reduction even if the partially perforated wall was still effective compared to the plain wall. PMID:25254260

Experimental studies on wave interactions of partially perforated wall under obliquely incident waves.

PubMed

Lee, Jong-In; Kim, Young-Taek; Shin, Sungwon

2014-01-01

This study presents wave height distribution in terms of stem wave evolution phenomena on partially perforated wall structures through three-dimensional laboratory experiments. The plain and partially perforated walls were tested to understand their effects on the stem wave evolution under the monochromatic and random wave cases with the various wave conditions, incident angle (from 10 to 40 degrees), and configurations of front and side walls. The partially perforated wall reduced the relative wave heights more effectively compared to the plain wall structure. Partially perforated walls with side walls showed a better performance in terms of wave height reduction compared to the structure without the side wall. Moreover, the relative wave heights along the wall were relatively small when the relative chamber width is large, within the range of the chamber width in this study. The wave spectra showed a frequency dependency of the wave energy dissipation. In most cases, the existence of side wall is a more important factor than the porosity of the front wall in terms of the wave height reduction even if the partially perforated wall was still effective compared to the plain wall.

An N-methyl-D-aspartate receptor-independent excitatory action of partial reduction of extracellular [Mg2+] in CA1-region of rat hippocampal slices.

PubMed

Hamon, B; Stanton, P K; Heinemann, U

1987-03-31

Partial reduction of [Mg2+]o from 2 to 1 mM markedly enhanced neuronal responses evoked by Schaffer collateral-commissural fiber stimulation in the CA1-region of rat hippocampal slices. The amplitude of extracellular population potentials recorded in the CA1-pyramidal cell layer and maximum dV/dt of extracellular population EPSP's recorded in the CA1-pyramidal apical dendritic layer were both increased. However, unlike findings from slices where Mg2+ was completely removed from the bathing medium, there was no spontaneous or evoked epileptiform activity, and the N-methyl-D-aspartate (NMDA) receptor antagonist 2-amino-5-phosphonovalerate (2-APV) did not antagonize the enhancement of evoked responses. These results indicate that, in addition to the participation of NMDA receptors in the epileptiform activity observed when Mg2+ is completely removed from the bathing medium, there is also an NMDA receptor-independent excitatory action of partial reduction of [Mg2+]o in hippocampal slices.

Assessing a change mechanism in a randomized home-visiting trial: Reducing disrupted maternal communication decreases infant disorganization.

PubMed

Tereno, Susana; Madigan, Sheri; Lyons-Ruth, Karlen; Plamondon, Andre; Atkinson, Leslie; Guedeney, Nicole; Greacen, Tim; Dugravier, Romain; Saias, Thomas; Guedeney, Antoine

2017-05-01

Although randomized interventions trials have been shown to reduce the incidence of disorganized attachment, no studies to date have identified the mechanisms of change responsible for such reductions. Maternal sensitivity has been assessed in various studies and shown to change with intervention, but in the only study to formally assess mediation, changes in maternal sensitivity did not mediate changes in infant security of attachment (Cicchetti, Rogosch, & Toth, 2006). Primary aims of the current randomized controlled intervention trial in a high-risk population were to fill gaps in the literature by assessing whether the intervention (a) reduced disorganization, (b) reduced disrupted maternal communication, and (c) whether reductions in disrupted maternal communication mediated changes in infant disorganization. The results indicated that, compared to controls (n = 52), both infant disorganization and disrupted maternal communication were significantly reduced in the intervention group (n = 65) that received regular home-visiting during pregnancy and the first year of life. Furthermore, reductions in disrupted maternal communication partially accounted for the observed reductions in infant disorganization compared to randomized controls. The results are discussed in relation to the societal cost effectiveness of early attachment-informed interventions for mothers and infants, as well as the importance of formally assessing underlying mechanisms of change in order to improve and appropriately target preventive interventions.

Simulation and optimization of pressure swing adsorption systmes using reduced-order modeling

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

Agarwal, A.; Biegler, L.; Zitney, S.

2009-01-01

Over the past three decades, pressure swing adsorption (PSA) processes have been widely used as energyefficient gas separation techniques, especially for high purity hydrogen purification from refinery gases. Models for PSA processes are multiple instances of partial differential equations (PDEs) in time and space with periodic boundary conditions that link the processing steps together. The solution of this coupled stiff PDE system is governed by steep fronts moving with time. As a result, the optimization of such systems represents a significant computational challenge to current differential algebraic equation (DAE) optimization techniques and nonlinear programming algorithms. Model reduction is one approachmore » to generate cost-efficient low-order models which can be used as surrogate models in the optimization problems. This study develops a reducedorder model (ROM) based on proper orthogonal decomposition (POD), which is a low-dimensional approximation to a dynamic PDE-based model. The proposed method leads to a DAE system of significantly lower order, thus replacing the one obtained from spatial discretization and making the optimization problem computationally efficient. The method has been applied to the dynamic coupled PDE-based model of a twobed four-step PSA process for separation of hydrogen from methane. Separate ROMs have been developed for each operating step with different POD modes for each of them. A significant reduction in the order of the number of states has been achieved. The reduced-order model has been successfully used to maximize hydrogen recovery by manipulating operating pressures, step times and feed and regeneration velocities, while meeting product purity and tight bounds on these parameters. Current results indicate the proposed ROM methodology as a promising surrogate modeling technique for cost-effective optimization purposes.« less

Reduction of Deviation Angle During Occlusion Therapy: In Partially Accommodative Esotropia with Moderate Amblyopia

PubMed Central

Chun, Bo Young; Kwon, Soon Jae; Chae, Sun Hwa

2007-01-01

Purpose To evaluate changes in ocular alignment in partially accommodative esotropic children age ranged from 3 to 8 years during occlusion therapy for amblyopia. Methods Angle measurements of twenty-two partially accommodative esotropic patients with moderate amblyopia were evaluated before and at 2 years after occlusion therapy. Results Mean deviation angle with glasses at the start of occlusion treatment was 19.45±5.97 PD and decreased to 12.14±12.96 PD at 2 years after occlusion therapy (p<0.01). After occlusion therapy, 9 (41%) cases were indications of surgery for residual deviation but if we had planned surgery before occlusion treatment, 18 (82%) of patients would have had surgery. There was a statistical relationship between increase of visual acuity ratio and decrease of deviation angle (r=-0.479, p=0.024). Conclusions There was a significant reduction of deviation angle of partially accommodative esotropic patients at 2 years after occlusion therapy. Our results suggest that occlusion therapy has an influence on ocular alignment in partially accommodative esotropic patients with amblyopia. PMID:17804922

Metal-insulator transition in nanocomposite VOx films formed by anodic electrodeposition

NASA Astrophysics Data System (ADS)

Tsui, Lok-kun; Hildebrand, Helga; Lu, Jiwei; Schmuki, Patrik; Zangari, Giovanni

2013-11-01

The ability to grow VO2 films by electrochemical methods would open a low-cost, easily scalable production route to a number of electronic devices. We have synthesized VOx films by anodic electrodeposition of V2O5, followed by partial reduction by annealing in Ar. The resulting films are heterogeneous, consisting of various metallic/oxide phases and including regions with VO2 stoichiometry. A gradual metal insulator transition with a nearly two order of magnitude change in film resistance is observed between room temperature and 140 °C. In addition, the films exhibit a temperature coefficient of resistance of ˜ -2.4%/ °C from 20 to 140 °C.

NLS clutching bearing cavity flow analysis

NASA Technical Reports Server (NTRS)

Tran, Ken; Chan, Daniel C.; Darian, Armen

1992-01-01

A flow model of the NLS clutching bearing cavity was built for 2-D axisymmetric viscous analysis. From the computational fluid dynamics (CFD) approach, the tangential force exerted on the surfaces of the inner race was integrated to calculate the dividing torque which, in conjunction with the resistance torque, was used to predict the operating speed of the inner race. In order to further reduce the inner race rotation, the swirling flow at the cavity inlet was partially redirected to generate an opposing torque. Thirty six slanted slots were incorporated into the anti-vortex rib to achieve this goal. A 3-D flow analysis performed on this configuration indicates a drastic reduction of the driving torque and inner race RPM.

Intelligent driving in traffic systems with partial lane discipline

NASA Astrophysics Data System (ADS)

Assadi, Hamid; Emmerich, Heike

2013-04-01

It is a most common notion in traffic theory that driving in lanes and keeping lane changes to a minimum leads to smooth and laminar traffic flow, and hence to increased traffic capacity. On the other hand, there exist persistent vehicular traffic systems that are characterised by habitual disregarding of lane markings, and partial or complete loss of laminar traffic flow. Here, we explore the stability of such systems through a microscopic traffic flow model, where the degree of lane-discipline is taken as a variable, represented by the fraction of drivers that disregard lane markings completely. The results show that lane-free traffic may win over completely ordered traffic at high densities, and that partially ordered traffic leads to the poorest overall flow, while not considering the crash probability. Partial order in a lane-free system is similar to partial disorder in a lane-disciplined system in that both lead to decreased traffic capacity. This could explain the reason why standard enforcement methods, which rely on continuous increase of order, often fail to incur order to lane-free traffic systems. The results also provide an insight into the cooperative phenomena in open systems with self-driven particles.

The reduction mechanism of chromite in the presence of a silica flux

NASA Astrophysics Data System (ADS)

Weber, P.; Eric, R. H.

1993-12-01

The reduction behavior of a natural chromite from the Bushveld Complex of South Africa was studied at 1300 °C to 1500 °C. Reduction was by graphite in the presence of silica. Thermo-gravimetric analysis, X-ray diffraction (XRD) analysis, energy-dispersive X-ray analysis (EDAX), and metallographic analysis were the experimental techniques used. Silica affected the reduction at and above 1400 °C. A two-stage reduction mechanism was established. The first stage, up to a reduction level of about 40 pct, is primarily confined to iron metallization, and zoning is observed in partially reduced chromites. In this stage, silica does not interfere with the reduction, which proceeds by an outward diffusion of Fe2+ ions and an inward diffusion of Mg2+ and Cr2+ ions. The second stage is primarily confined to chromium metallization, and formation of a silicate slag alters the reduction mechanism. The slag phase agglomerates and even embeds partially reduced chromite particles. An ion-exchange reaction between the re-ducible cations (Cr3+ and Fe2+) in the spinel and the dissolved cations (Al3+ and Mg2+) in the slag allows further reduction. Once the reducible cations are dissolved in the slag phase, they are reduced to the metallic state at sites where there is contact with the reductant.

The effects of partial use of formula diet on weight reduction and metabolic variables in obese type 2 diabetic patients--multicenter trial.

PubMed

Shirai, Kohji; Saiki, Atsuhito; Oikawa, Shinichi; Teramoto, Tamio; Yamada, Nobuhiro; Ishibashi, Shun; Tada, Norio; Miyazaki, Shigeru; Inoue, Ikuo; Murano, Shunichi; Sakane, Naoki; Satoh-Asahara, Noriko; Bujo, Hideaki; Miyashita, Yoh; Saito, Yasushi

2013-01-01

To clarify the usefulness of protein-sparing modified formula diet in obese type 2 diabetic patients, the effects of partial use of formula diet on weight reduction and changes in related metabolic variables, and the improving rates of risk factors per 1% body weight reduction, were compared with those of conventional subcaloric diet. Obese patients [BMI >25 kg/m²] with diabetic mellitus were randomly assigned to a low-caloric diet with partial use of formula diet group (FD, n = 119) and a conventional low-caloric diet group (CD, n = 110). Subjects in FD took one pack of formula diet (MicroDiet®, 240 kcal/pack) in place of one of three daily low-caloric meals for 24 weeks. Total daily calorie prescribed was same. Weight reduction was greater in FD than in CD (week 24: -3.5 vs -1.4 kg; all p < 0.001). Systolic blood pressure decreased significantly only in FD. HbA1c reduction was greater in FD than in CD. HDL-cholesterol increased significantly more in FD than in CD (week 24: +2.8 vs. +0.6 mg/dl, p < 0.001). Among several improving rates (%) of risk factors/1% body weight reduction, those of HbA1c at weeks 16 and 24, triglyceride at week 8 and HDL-cholesterol at week 24, were significantly higher in FD than CD. Doses of sulfonylurea and thiazolidinedione were significantly decreased in FD than in CD. Partial use of formula diet was much more effective in reducing body weight, and also in improving coronary risk factors than conventional diet in part due to reduced body weight through decreased energy diet intake and due to dietary composition of the formula diet. © 2013 Asian Oceanian Association for the Study of Obesity . Published by Elsevier Ltd. All rights reserved.

Effect of partial reduction of pork meat on the physicochemical and sensory quality of dry ripened sausages: development of a healthy venison salchichon.

PubMed

Utrilla, M C; García Ruiz, A; Soriano, A

2014-12-01

The minimum percentage of pork meat to be added to traditional venison salchichon has been determined in order to ensure a nutritionally healthier product without impairing physicochemical or sensory properties. Six types of salchichon were made using lean venison and a varying amount of pork meat (40%, 30%, 25%, 20%, 15% and 10%). All types displayed appropriate physicochemical properties (pH, aw, moisture loss) and color (L*, a*, b*) during ripening, as well as adequate levels of lipolysis (acidity index) and lipid oxidation (TBARS). Moreover, reduction of the amount of pork meat in salchichon prompted an increase in the relative percentage of polyunsaturated fatty acids. It was concluded that in making venison salchichon, the addition of a 25% pork meat is sufficient to ensure a satisfactory ripening process and physicochemical characteristics, optimal organoleptic properties and a higher percentage of polyunsaturated fatty acids than that found in traditional venison salchichon. Copyright © 2014 Elsevier Ltd. All rights reserved.

Purification and characterization of Aspergillus niger exo-1,4-glucosidase.

PubMed

Freedberg, I M; Levin, Y; Kay, C M; McCubbin, W D; Katchalski-Katzir, E

1975-06-24

A specific exo-1,4-glucosidase (1,4-alpha-D-glucan glucohydrooase, EC 3.2.1.3) from Aspergillus niger has been partially purified and subsequently characterized by biochemical, physico-chemical and optical methods. Molecular sieve chromatography yields an enzyme with maximal activity at pH 4.2-4.5 close to its isoelectric point. Reduction and carboxymethylation leads to complete loss of activity and O-acetylation of 3 of the 13 tyrosine residues results in loss of 20 % of the activity. Sodium dodecylsulfate-polyacrylamide gel electrophoresis indicates that the native enzyme consists of two major components of molecular weights 63 000 and 57 500, respectively. Small amounts of dissociated material of molecular weight 28 000 and 16 000 as well as aggregates of the order of 100 000 are also present to the extent of 2-5% of the total potein. Following reduction and carboxymethylation under forcing conditions, the bands around 60 000 diminish and the 28 000-30 000, 16 000 and aggregate bands are dominant...

The convergence of the order sequence and the solution function sequence on fractional partial differential equation

NASA Astrophysics Data System (ADS)

Rusyaman, E.; Parmikanti, K.; Chaerani, D.; Asefan; Irianingsih, I.

2018-03-01

One of the application of fractional ordinary differential equation is related to the viscoelasticity, i.e., a correlation between the viscosity of fluids and the elasticity of solids. If the solution function develops into function with two or more variables, then its differential equation must be changed into fractional partial differential equation. As the preliminary study for two variables viscoelasticity problem, this paper discusses about convergence analysis of function sequence which is the solution of the homogenous fractional partial differential equation. The method used to solve the problem is Homotopy Analysis Method. The results show that if given two real number sequences (αn) and (βn) which converge to α and β respectively, then the solution function sequences of fractional partial differential equation with order (αn, βn) will also converge to the solution function of fractional partial differential equation with order (α, β).

Mode Reduction and Upscaling of Reactive Transport Under Incomplete Mixing

NASA Astrophysics Data System (ADS)

Lester, D. R.; Bandopadhyay, A.; Dentz, M.; Le Borgne, T.

2016-12-01

Upscaling of chemical reactions in partially-mixed fluid environments is a challenging problem due to the detailed interactions between inherently nonlinear reaction kinetics and complex spatio-temporal concentration distributions under incomplete mixing. We address this challenge via the development of an order reduction method for the advection-diffusion-reaction equation (ADRE) via projection of the reaction kinetics onto a small number N of leading eigenmodes of the advection-diffusion operator (the so-called "strange eigenmodes" of the flow) as an N-by-N nonlinear system, whilst mixing dynamics only are projected onto the remaining modes. For simple kinetics and moderate Péclet and Damkhöler numbers, this approach yields analytic solutions for the concentration mean, evolving spatio-temporal distribution and PDF in terms of the well-mixed reaction kinetics and mixing dynamics. For more complex kinetics or large Péclet or Damkhöler numbers only a small number of modes are required to accurately quantify the mixing and reaction dynamics in terms of the concentration field and PDF, facilitating greatly simplified approximation and analysis of reactive transport. Approximate solutions of this low-order nonlinear system provide quantiative predictions of the evolving concentration PDF. We demonstrate application of this method to a simple random flow and various mass-action reaction kinetics.

Multifactor-Dimensionality Reduction Reveals High-Order Interactions among Estrogen-Metabolism Genes in Sporadic Breast Cancer

PubMed Central

Ritchie, Marylyn D.; Hahn, Lance W.; Roodi, Nady; Bailey, L. Renee; Dupont, William D.; Parl, Fritz F.; Moore, Jason H.

2001-01-01

One of the greatest challenges facing human geneticists is the identification and characterization of susceptibility genes for common complex multifactorial human diseases. This challenge is partly due to the limitations of parametric-statistical methods for detection of gene effects that are dependent solely or partially on interactions with other genes and with environmental exposures. We introduce multifactor-dimensionality reduction (MDR) as a method for reducing the dimensionality of multilocus information, to improve the identification of polymorphism combinations associated with disease risk. The MDR method is nonparametric (i.e., no hypothesis about the value of a statistical parameter is made), is model-free (i.e., it assumes no particular inheritance model), and is directly applicable to case-control and discordant-sib-pair studies. Using simulated case-control data, we demonstrate that MDR has reasonable power to identify interactions among two or more loci in relatively small samples. When it was applied to a sporadic breast cancer case-control data set, in the absence of any statistically significant independent main effects, MDR identified a statistically significant high-order interaction among four polymorphisms from three different estrogen-metabolism genes. To our knowledge, this is the first report of a four-locus interaction associated with a common complex multifactorial disease. PMID:11404819

Kinetic and Thermodynamic Characterization of the Cobalt and Manganese Oxyhydroxide Cores Formed in Horse Spleen Ferritin

NASA Technical Reports Server (NTRS)

Zhang, Bo; Harb, John N.; Davis, Robert C.; Kim, Jae-Woo; Chu, Sang-Hyon; Choi, Sang; Miller, Tim; Watt, Gerald D.

2004-01-01

Horse spleen ferritin (HoSF) containing 800-1500 cobalt or 250-1200 manganese atoms as Co(O)OH and Mn(O)OH mineral cores within the HoSF interior (Co-HoSF and Mn-HoSF) was synthesized, and the chemical reactivity, kinetics of reduction, and the reduction potentials were measured. Microcoulometric and chemical reduction of HoSF containing the M(O)OH mineral core (M = Co or Mn) was rapid and quantitative with a reduction stoichiometry of 1.05+/-0.10 e/M forming a stable M(OH)2 mineral core. At pH 9.0, ascorbic acid (AH2), a two-electron reductant, effectively reduced the mineral cores; however, the reaction was incomplete and rapidly reached equilibrium. The addition of excess AH2 shifted the reaction to completion with a M(3+)/AH2 stoichiometry of 1.9-2.1, consistent with a single electron per metal atom reduction. The rate of reaction between M(0)OH and excess AH2 was measured by monitoring the decrease in mineral core absorbance with time. The reaction was first order in each reactant with second-order rate constants of 0.53 and 4.74/M/min, respectively, for Co- and Mn-HoSF at pH 9.0. From the variation of absorbance with increasing AH2 concentration, equilibrium constants at pH 9.0 of 5.0+/-1.9 for Co-HoSF and 2.9+/-0.9 for Mn-HoSF were calculated for 2M(O)OH + AH2 = 2M(OH)2 f D, where AH2 and D are ascorbic acid and dehydroascorbic acid, respectively. Consistent with these equilibrium constants, the standard potential for the reduction of Co(III)-HoSF is 42 mV more positive than that of the ascorbic acid reaction, while the standard potential of Mn(III)-HoSF is 27 mV positive relative to AH2. Fe(2+) in solution with Co- and Mn-HoSF under anaerobic conditions was oxidized to form Fe(O)OH within the HoSF interior, resulting in partial displacement of the Co or Mn by iron.

Aminosugar derivatives as potential anti-human immunodeficiency virus agents.

PubMed Central

Karpas, A; Fleet, G W; Dwek, R A; Petursson, S; Namgoong, S K; Ramsden, N G; Jacob, G S; Rademacher, T W

1988-01-01

Recent data suggest that aminosugar derivatives which inhibit glycoprotein processing have potential anti-human immunodeficiency virus (HIV) activity. These inhibitory effects may be due to disruption of cell fusion and subsequent cell-cell transmission of the acquired immunodeficiency syndrome (AIDS) virus. Free virus particles able to bind CD4-positive cells are still produced in the presence of these compounds with only partial reduction of infectivity. We now report a method to score in parallel both the degree of antiviral activity and the effect on cell division of aminosugar derivatives. We find that (i) the compounds 1,4-dideoxy-1,4-imino-L-arabinitol and N-(5-carboxymethyl-1-pentyl)-1,5-imino-L-fucitol partially inhibit the cytopathic effect (giant cell formation, etc.) of HIV and yield of infectious virus; (ii) the compounds N-methyldeoxynojirimycin and N-ethyldeoxynojirimycin reduce the yield of infectious HIV by an order of four and three logarithms, respectively; and (iii) one compound, N-butyldeoxynojirimycin, of the 47 compounds previously screened reduces infectious viral particles by a logarithmic order greater than five at noncytotoxic concentrations. In addition, long-term growth of infected cells in the presence of N-butyldeoxynojirimycin gradually decreases the proportion of infected cells, leading to eventual elimination of HIV from culture. This result suggests that replication is associated with cytolysis. The ability to break the cycle of replication and reinfection has important implications in the chemotherapy of AIDS. PMID:3264071

Ordering policies of a deteriorating item in an EOQ model with backorder under two-level partial trade credit

NASA Astrophysics Data System (ADS)

Molamohamadi, Zohreh; Arshizadeh, Rahman; Ismail, Napsiah

2015-05-01

In the classical inventory model, it was assumed that the retailer must settle the accounts of the purchased items as soon as they are received. In practice, however, the supplier usually offers a full or partial delay period to the retailer to pay for the amount of the purchasing costs. In the partial trade credit contract, which is mostly applied to avoid non-payment risks, the retailer must pay for a portion of the purchased goods at the time of ordering and may delay settling the rest until the end of the predefined agreed upon period, so-called credit period. This paper assumes a two-level partial trade credit where both supplier and retailer offer a partial trade credit to their downstream members. The objective here is to determine the retailer's ordering policy of a deteriorating item by formulating his economic order quantity (EOQ) inventory system with backorder as a cost minimization problem. The sensitivity of the variables on different parameters has been also analyzed by applying numerical examples.

Genomic Characterization of Methanomicrobiales Reveals Three Classes of Methanogens

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

Anderson, Iain; Ulrich, Luke; Lupa, Boguslaw

2009-01-01

Background Methanomicrobiales is the least studied order of methanogens. While these organisms appear to be more closely related to the Methanosarcinales in ribosomal-based phylogenetic analyses, they are metabolically more similar to Class I methanogens. Methodology/Principal Findings In order to improve our understanding of this lineage, we have completely sequenced the genomes of two members of this order, Methanocorpusculum labreanum Z and Methanoculleus marisnigri JR1, and compared them with the genome of a third, Methanospirillum hungatei JF-1. Similar to Class I methanogens, Methanomicrobiales use a partial reductive citric acid cycle for 2-oxoglutarate biosynthesis, and they have the Eha energy-converting hydrogenase. Inmore » common with Methanosarcinales, Methanomicrobiales possess the Ech hydrogenase and at least some of them may couple formylmethanofuran formation and heterodisulfide reduction to transmembrane ion gradients. Uniquely, M. labreanum and M. hungatei contain hydrogenases similar to the Pyrococcus furiosus Mbh hydrogenase, and all three Methanomicrobiales have anti-sigma factor and anti-anti-sigma factor regulatory proteins not found in other methanogens. Phylogenetic analysis based on seven core proteins of methanogenesis and cofactor biosynthesis places the Methanomicrobiales equidistant from Class I methanogens and Methanosarcinales. Conclusions/Significance Our results indicate that Methanomicrobiales, rather than being similar to Class I methanogens or Methanomicrobiales, share some features of both and have some unique properties. We find that there are three distinct classes of methanogens: the Class I methanogens, the Methanomicrobiales (Class II), and the Methanosarcinales (Class III).« less

Noise reduction tests of large-scale-model externally blown flap using trailing-edge blowing and partial flap slot covering. [jet aircraft noise reduction

NASA Technical Reports Server (NTRS)

Mckinzie, D. J., Jr.; Burns, R. J.; Wagner, J. M.

1976-01-01

Noise data were obtained with a large-scale cold-flow model of a two-flap, under-the-wing, externally blown flap proposed for use on future STOL aircraft. The noise suppression effectiveness of locating a slot conical nozzle at the trailing edge of the second flap and of applying partial covers to the slots between the wing and flaps was evaluated. Overall-sound-pressure-level reductions of 5 db occurred below the wing in the flyover plane. Existing models of several noise sources were applied to the test results. The resulting analytical relation compares favorably with the test data. The noise source mechanisms were analyzed and are discussed.

Unidimensional factor models imply weaker partial correlations than zero-order correlations.

PubMed

van Bork, Riet; Grasman, Raoul P P P; Waldorp, Lourens J

2018-06-01

In this paper we present a new implication of the unidimensional factor model. We prove that the partial correlation between two observed variables that load on one factor given any subset of other observed variables that load on this factor lies between zero and the zero-order correlation between these two observed variables. We implement this result in an empirical bootstrap test that rejects the unidimensional factor model when partial correlations are identified that are either stronger than the zero-order correlation or have a different sign than the zero-order correlation. We demonstrate the use of the test in an empirical data example with data consisting of fourteen items that measure extraversion.

Evaluation of analytical performance based on partial order methodology.

PubMed

Carlsen, Lars; Bruggemann, Rainer; Kenessova, Olga; Erzhigitov, Erkin

2015-01-01

Classical measurements of performances are typically based on linear scales. However, in analytical chemistry a simple scale may be not sufficient to analyze the analytical performance appropriately. Here partial order methodology can be helpful. Within the context described here, partial order analysis can be seen as an ordinal analysis of data matrices, especially to simplify the relative comparisons of objects due to their data profile (the ordered set of values an object have). Hence, partial order methodology offers a unique possibility to evaluate analytical performance. In the present data as, e.g., provided by the laboratories through interlaboratory comparisons or proficiency testings is used as an illustrative example. However, the presented scheme is likewise applicable for comparison of analytical methods or simply as a tool for optimization of an analytical method. The methodology can be applied without presumptions or pretreatment of the analytical data provided in order to evaluate the analytical performance taking into account all indicators simultaneously and thus elucidating a "distance" from the true value. In the present illustrative example it is assumed that the laboratories analyze a given sample several times and subsequently report the mean value, the standard deviation and the skewness, which simultaneously are used for the evaluation of the analytical performance. The analyses lead to information concerning (1) a partial ordering of the laboratories, subsequently, (2) a "distance" to the Reference laboratory and (3) a classification due to the concept of "peculiar points". Copyright © 2014 Elsevier B.V. All rights reserved.

75 FR 59742 - Public Land Order No. 7752; Partial Revocation of a Light Station Reservation; Washington

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-28

... DEPARTMENT OF THE INTERIOR Bureau of Land Management [LLOR-936000-L14300000-FQ0000; HAG-09-0002; WAOR-22197 K] Public Land Order No. 7752; Partial Revocation of a Light Station Reservation; Washington...: The reservation of public land for the Lime Kiln Light Station created by an Executive Order dated...

42 CFR 419.45 - Payment and copayment reduction for devices replaced without cost or when full or partial credit...

Code of Federal Regulations, 2010 CFR

2010-10-01

... of reduction to the APC payment. (1) The amount of the reduction to the APC payment made under... be applied if the device implanted during a procedure assigned to the APC had transitional pass-through status under § 419.66. (2) The amount of the reduction to the APC payment made under paragraph (a...

Magnetocaloric effect in amorphous and partially crystallized Fe{sub 40}Ni{sub 38}Mo{sub 4}B{sub 18} alloys

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

Thanveer, T.; Thomas, S., E-mail: senoythomas@gmail.com; Ramanujan, R. V.

A study of magnetocaloric effect in amorphous and partially crystallized Fe{sub 40}Ni{sub 38}Mo{sub 4}B{sub 18} alloys is reported. Amorphous Fe{sub 40}Ni{sub 38}Mo{sub 4}B{sub 18}, near its magnetic ordering temperature (600 K) showed a magnetic entropy change ΔS{sub M} of 1.1 J/KgK and a relative cooling power of 36 J/Kg in a field change of 10 kOe. Amorphous samples were partially crystallized by annealing at 700 K at different time intervals. Partially crystallized samples showed two distinct magnetic ordering temperature, one corresponding to the precipitated FeNi nanocrystals and the other one corresponding to the boron rich amorphous matrix. Magnetic ordering temperaturemore » of the residual amorphous matrix got shifted to the lower temperatures on increasing the annealing duration. Partially crystallised samples showed a magnetic entropy change of about 0.27 J/kgK near the magnetic ordering temperature of the amorphous matrix (540 K) in a field change of 10 kOe. The decrease in ΔS{sub M} on partial crystallisation is attributed to the biphasic magnetic nature of the sample.« less

In-Space Manufacturing: Pioneering a Sustainable Path to Mars

NASA Technical Reports Server (NTRS)

Werkheiser, Niki

2015-01-01

In order to provide meaningful impacts to exploration technology needs, the In-Space Manufacturing (ISM) Initiative must influence exploration systems design now. In-space manufacturing offers: dramatic paradigm shift in the development and creation of space architectures; efficiency gain and risk reduction for low Earth orbit and deep space exploration; and "pioneering" approach to maintenance, repair, and logistics leading to sustainable, affordable supply chain model. In order to develop application-based capabilities in time to support NASA budget and schedule, ISM must be able to leverage the significant commercial developments, which requires innovative, agile collaborative mechanisms (contracts, challenges, SBIR's, etc.); and NASA-unique investments to focus primarily on adapting the technologies and processes to the microgravity environment. We must do the foundational work - it is the critical path for taking these technologies from lab curiosities to institutionalized capabilities: characterize, certify, institutionalize, design for Additive Manufacturing (AM). Ideally, International Space Station (ISS) U.S. lab rack or partial rack space should be identified for in-space manufacturing utilization in order to continue technology development of a suite of capabilities required for exploration missions, as well as commercialization on ISS.

Modeling of the oxygen reduction reaction for dense LSM thin films

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

Yang, Tao; Liu, Jian; Yu, Yang

In this study, the oxygen reduction reaction mechanism is investigated using numerical methods on a dense thin (La 1-xSr x) yMnO 3±δ film deposited on a YSZ substrate. This 1-D continuum model consists of defect chemistry and elementary oxygen reduction reaction steps coupled via reaction rates. The defect chemistry model contains eight species including cation vacancies on the A- and B-sites. The oxygen vacancy is calculated by solving species transportation equations in multiphysics simulations. Due to the simple geometry of a dense thin film, the oxygen reduction reaction was reduced to three elementary steps: surface adsorption and dissociation, incorporation onmore » the surface, and charge transfer across the LSM/YSZ interface. The numerical simulations allow for calculation of the temperature- and oxygen partial pressure-dependent properties of LSM. The parameters of the model are calibrated with experimental impedance data for various oxygen partial pressures at different temperatures. The results indicate that surface adsorption and dissociation is the rate-determining step in the ORR of LSM thin films. With the fine-tuned parameters, further quantitative analysis is performed. The activation energy of the oxygen exchange reaction and the dependence of oxygen non-stoichiometry on oxygen partial pressure are also calculated and verified using the literature results.« less

Modeling of the oxygen reduction reaction for dense LSM thin films

DOE PAGES

Yang, Tao; Liu, Jian; Yu, Yang; ...

2017-10-17

In this study, the oxygen reduction reaction mechanism is investigated using numerical methods on a dense thin (La 1-xSr x) yMnO 3±δ film deposited on a YSZ substrate. This 1-D continuum model consists of defect chemistry and elementary oxygen reduction reaction steps coupled via reaction rates. The defect chemistry model contains eight species including cation vacancies on the A- and B-sites. The oxygen vacancy is calculated by solving species transportation equations in multiphysics simulations. Due to the simple geometry of a dense thin film, the oxygen reduction reaction was reduced to three elementary steps: surface adsorption and dissociation, incorporation onmore » the surface, and charge transfer across the LSM/YSZ interface. The numerical simulations allow for calculation of the temperature- and oxygen partial pressure-dependent properties of LSM. The parameters of the model are calibrated with experimental impedance data for various oxygen partial pressures at different temperatures. The results indicate that surface adsorption and dissociation is the rate-determining step in the ORR of LSM thin films. With the fine-tuned parameters, further quantitative analysis is performed. The activation energy of the oxygen exchange reaction and the dependence of oxygen non-stoichiometry on oxygen partial pressure are also calculated and verified using the literature results.« less

Oscillation of certain higher-order neutral partial functional differential equations.

PubMed

Li, Wei Nian; Sheng, Weihong

2016-01-01

In this paper, we study the oscillation of certain higher-order neutral partial functional differential equations with the Robin boundary conditions. Some oscillation criteria are established. Two examples are given to illustrate the main results in the end of this paper.

Pseudo almost periodic solutions to some systems of nonlinear hyperbolic second-order partial differential equations

NASA Astrophysics Data System (ADS)

Al-Islam, Najja Shakir

In this Dissertation, the existence of pseudo almost periodic solutions to some systems of nonlinear hyperbolic second-order partial differential equations is established. For that, (Al-Islam [4]) is first studied and then obtained under some suitable assumptions. That is, the existence of pseudo almost periodic solutions to a hyperbolic second-order partial differential equation with delay. The second-order partial differential equation (1) represents a mathematical model for the dynamics of gas absorption, given by uxt+a x,tux=Cx,t,u x,t , u0,t=4 t, 1 where a : [0, L] x RR , C : [0, L] x R x RR , and ϕ : RR are (jointly) continuous functions ( t being the greatest integer function) and L > 0. The results in this Dissertation generalize those of Poorkarimi and Wiener [22]. Secondly, a generalization of the above-mentioned system consisting of the non-linear hyperbolic second-order partial differential equation uxt+a x,tux+bx,t ut+cx,tu=f x,t,u, x∈ 0,L,t∈ R, 2 equipped with the boundary conditions ux,0 =40x, u0,t=u 0t, uxx,0=y 0x, x∈0,L, t∈R, 3 where a, b, c : [0, L ] x RR and f : [0, L] x R x RR are (jointly) continuous functions is studied. Under some suitable assumptions, the existence and uniqueness of pseudo almost periodic solutions to particular cases, as well as the general case of the second-order hyperbolic partial differential equation (2) are studied. The results of all studies contained within this text extend those obtained by Aziz and Meyers [6] in the periodic setting.

The lattice of trumping majorization for 4D probability vectors and 2D catalysts.

PubMed

Bosyk, Gustavo M; Freytes, Hector; Bellomo, Guido; Sergioli, Giuseppe

2018-02-27

The transformation of an initial bipartite pure state into a target one by means of local operations and classical communication and entangled-assisted by a catalyst defines a partial order between probability vectors. This partial order, so-called trumping majorization, is based on tensor products and the majorization relation. Here, we aim to study order properties of trumping majorization. We show that the trumping majorization partial order is indeed a lattice for four dimensional probability vectors and two dimensional catalysts. In addition, we show that the subadditivity and supermodularity of the Shannon entropy on the majorization lattice are inherited by the trumping majorization lattice. Finally, we provide a suitable definition of distance for four dimensional probability vectors.

Reduced basis ANOVA methods for partial differential equations with high-dimensional random inputs

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

Liao, Qifeng, E-mail: liaoqf@shanghaitech.edu.cn; Lin, Guang, E-mail: guanglin@purdue.edu

2016-07-15

In this paper we present a reduced basis ANOVA approach for partial deferential equations (PDEs) with random inputs. The ANOVA method combined with stochastic collocation methods provides model reduction in high-dimensional parameter space through decomposing high-dimensional inputs into unions of low-dimensional inputs. In this work, to further reduce the computational cost, we investigate spatial low-rank structures in the ANOVA-collocation method, and develop efficient spatial model reduction techniques using hierarchically generated reduced bases. We present a general mathematical framework of the methodology, validate its accuracy and demonstrate its efficiency with numerical experiments.

Dividers for reduction of aerodynamic drag of vehicles with open cavities

NASA Technical Reports Server (NTRS)

Storms, Bruce L. (Inventor)

2007-01-01

A drag-reduction concept for vehicles with open cavities includes dividing a cavity into smaller adjacent cavities through installation of one or more vertical dividers. The dividers may extend the full depth of the cavity or only partial depth. In either application, the top of the dividers are typically flush with the top of the bed or cargo bay of the vehicle. The dividers may be of any material, but are strong enough for both wind loads and forces encountered during cargo loading/unloading. For partial depth dividers, a structural angle may be desired to increase strength.

On the complete and partial integrability of non-Hamiltonian systems

NASA Astrophysics Data System (ADS)

Bountis, T. C.; Ramani, A.; Grammaticos, B.; Dorizzi, B.

1984-11-01

The methods of singularity analysis are applied to several third order non-Hamiltonian systems of physical significance including the Lotka-Volterra equations, the three-wave interaction and the Rikitake dynamo model. Complete integrability is defined and new completely integrable systems are discovered by means of the Painlevé property. In all these cases we obtain integrals, which reduce the equations either to a final quadrature or to an irreducible second order ordinary differential equation (ODE) solved by Painlevé transcendents. Relaxing the Painlevé property we find many partially integrable cases whose movable singularities are poles at leading order, with In( t- t0) terms entering at higher orders. In an Nth order, generalized Rössler model a precise relation is established between the partial fulfillment of the Painlevé conditions and the existence of N - 2 integrals of the motion.

77 FR 13566 - Notice of Availability for Exclusive, Non-Exclusive, or Partially-Exclusive Licensing of an...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-07

... invention set forth in ``Radiation Detector System for Locating and Identifying Special Nuclear Material in..., or Partially-Exclusive Licensing of an Invention Concerning a Radiation Detector System for Locating and Identifying Special Nuclear Material in Moving Vehicles AGENCY: Defense Threat Reduction Agency...

An evaluation of the partial reflection technique and results from the winter 1971 - 1972 D region

NASA Technical Reports Server (NTRS)

Dasilva, L. C.; Bowhill, S. A.

1974-01-01

Fundamental physical and chemical processes, and measurement techniques on the D region are reviewed. Design considerations about a partial-reflection system are made, and the main characteristics of the partial-reflection system at the University of Illinois are presented. The nature of the partial reflections is discussed, particularly reflections produced by gradients in electron density and by random fluctuations in a locally homogeneous random medium. Possible reasons for disagreement between partial reflections and rocket measurements are discussed. Some suggestions are made to improve partial-reflection data reduction, including the use of only maximums of the reflections and deconvolution of the data. The results of partial-reflection measurements at Wallops Island, Virginia during the 1971-1972 winter are presented and compared to rocket measurements.

Propagation and coherence properties of higher order partially coherent dark hollow beams in turbulence

NASA Astrophysics Data System (ADS)

Eyyuboğlu, Halil Tanyer

2008-02-01

We formulate and evaluate in terms of graphical outputs, source and receiver plane expressions, the complex degree of coherence, beam size variation and power in bucket performance for higher order partially coherent dark hollow beams propagating in turbulent atmosphere. Our formulation is able to cover square, rectangular, circular, elliptical geometries for dark hollow and flat-topped beams in one single expression. From the graphical outputs of the receiver plane, it is observed that higher order partially coherent dark hollow beams will initially develop an outer ring around a central lobe, but will eventually evolve towards a Gaussian shape as the propagation distance is extended. It is further observed that stronger turbulence levels and greater partial coherence have similar effects on beam profile. During propagation, modulus of complex degree of coherence of partially coherent dark hollow beams appears to rise above that of the source plane values, reaching as high as near unity. Beam size analysis shows that, among the types examined, (nearly) flat-topped beam experiences the least beam expansion. Power in bucket analysis indicates that lowest order square fully coherent dark beam offers the best power capturing.

Convergence of excitatory and inhibitory hair cell transmitters shapes vestibular afferent responses.

PubMed

Holstein, Gay R; Rabbitt, Richard D; Martinelli, Giorgio P; Friedrich, Victor L; Boyle, Richard D; Highstein, Stephen M

2004-11-02

The vestibular semicircular canals respond to angular acceleration that is integrated to angular velocity by the biofluid mechanics of the canals and is the primary origin of afferent responses encoding velocity. Surprisingly, some afferents actually report angular acceleration. Our data indicate that hair-cell/afferent synapses introduce a mathematical derivative in these afferents that partially cancels the biomechanical integration and results in discharge rates encoding angular acceleration. We examined the role of convergent synaptic inputs from hair cells to this mathematical differentiation. A significant reduction in the order of the differentiation was observed for low-frequency stimuli after gamma-aminobutyric acid type B receptor antagonist administration. Results demonstrate that gamma-aminobutyric acid participates in shaping the temporal dynamics of afferent responses.

Ordering Transformations in High-Entropy Alloys

NASA Astrophysics Data System (ADS)

Singh, Prashant; Johnson, Duane D.

The high-temperature disordered phase of multi-component alloys, including high-entropy alloys (HEA), generally must experience segregation or else passes through partially-ordered phases to reach the low-temperature, fully-ordered phase. Our first-principles KKR-CPA-based atomic short-range ordering (SRO) calculations (analyzed as concentration-waves) reveal the competing partially and fully ordered phases in HEA, and these phases can be then directly assessed from KKR-CPA results in larger unit cells [Phys. Rev. B 91, 224204 (2015)]. For AlxCrFeNiTi0.25, Liu et al. [J Alloys Compd 619, 610 (2015)] experimentally find FCC+BCC coexistence that changes to BCC with increasing Al (x from 0-to-1), which then exhibits a partially-ordered B2 at low temperatures. CALPHAD (Calculation of Phase Diagrams) predicts a region with L21+B2 coexistence. From KKR-CPA calculations, we find crossover versus Al from FCC+BCC coexistence to BCC, as observed, and regions for partially-order B2+L21 coexistence, as suggest by CALPHAD. Our combined first-principles KKR-CPA method provides a powerful approach in predicting SRO and completing long-range order in HEA and other complex alloys. Supported by the U.S. DOE, Office of Science, Basic Energy Sciences, Materials Science and Engineering Division. Work was performed at Ames Laboratory, which is operated by Iowa State University for the U.S. DOE under Contract #DE-AC02-07CH11358.

Partial Tmem106b reduction does not correct abnormalities due to progranulin haploinsufficiency.

PubMed

Arrant, Andrew E; Nicholson, Alexandra M; Zhou, Xiaolai; Rademakers, Rosa; Roberson, Erik D

2018-06-22

Loss of function mutations in progranulin (GRN) are a major cause of frontotemporal dementia (FTD). Progranulin is a secreted glycoprotein that localizes to lysosomes and is critical for proper lysosomal function. Heterozygous GRN mutation carriers develop FTD with TDP-43 pathology and exhibit signs of lysosomal dysfunction in the brain, with increased levels of lysosomal proteins and lipofuscin accumulation. Homozygous GRN mutation carriers develop neuronal ceroid lipofuscinosis (NCL), an earlier-onset lysosomal storage disorder caused by severe lysosomal dysfunction. Multiple genome-wide association studies have shown that risk of FTD in GRN mutation carriers is modified by polymorphisms in TMEM106B, which encodes a lysosomal membrane protein. Risk alleles of TMEM106B may increase TMEM106B levels through a variety of mechanisms. Brains from FTD patients with GRN mutations exhibit increased TMEM106B expression, and protective TMEM106B polymorphisms are associated with decreased TMEM106B expression. Together, these data raise the possibility that reduction of TMEM106B levels may protect against the pathogenic effects of progranulin haploinsufficiency. We crossed Tmem106b +/- mice with Grn +/- mice, which model the progranulin haploinsufficiency of GRN mutation carriers and develop age-dependent social deficits and lysosomal abnormalities in the brain. We tested whether partial Tmem106b reduction could normalize the social deficits and lysosomal abnormalities of Grn +/- mice. Partial reduction of Tmem106b levels did not correct the social deficits of Grn +/- mice. Tmem106b reduction also failed to normalize most lysosomal abnormalities of Grn +/- mice, except for β-glucuronidase activity, which was suppressed by Tmem106b reduction and increased by progranulin insufficiency. These data do not support the hypothesis that Tmem106b reduction protects against the pathogenic effects of progranulin haploinsufficiency, but do show that Tmem106b reduction normalizes some lysosomal phenotypes in Grn +/- mice.

An Isotonic Partial Credit Model for Ordering Subjects on the Basis of Their Sum Scores

ERIC Educational Resources Information Center

Ligtvoet, Rudy

2012-01-01

In practice, the sum of the item scores is often used as a basis for comparing subjects. For items that have more than two ordered score categories, only the partial credit model (PCM) and special cases of this model imply that the subjects are stochastically ordered on the common latent variable. However, the PCM is very restrictive with respect…

75 FR 41237 - Public Land Order No. 7745; Partial Revocation of Power Site Reserve Nos. 510 and No. 515; Montana

Federal Register 2010, 2011, 2012, 2013, 2014

2010-07-15

... MTM 41534] Public Land Order No. 7745; Partial Revocation of Power Site Reserve Nos. 510 and No. 515... of public lands withdrawn for Power Site Reserve Nos. 510 and 515. This order also opens the lands to... INFORMATION: The Bureau of Land Management has determined that portions of Power Site Reserve Nos. 510 and 515...

Partial reinforcement, extinction, and placebo analgesia

PubMed Central

Yeung, Siu Tsin Au; Colagiuri, Ben; Lovibond, Peter F.; Colloca, Luana

2014-01-01

Numerous studies indicate that placebo analgesia can be established via conditioning procedures. However, these studies have exclusively involved conditioning under continuous reinforcement. Thus, it is currently unknown whether placebo analgesia can be established under partial reinforcement and how durable any such effect would be. We tested this possibility using electro-cutaneous pain in healthy volunteers. Sixty undergraduates received placebo treatment (activation of a sham electrode) under the guise of an analgesic trial. The participants were randomly allocated to different conditioning schedules, namely continuous reinforcement (CRF), partial reinforcement (PRF), or control (no conditioning). Conditioning was achieved by surreptitiously reducing pain intensity during training when the placebo was activated compared with when it was inactive. For the CRF group, the placebo was always followed by a surreptitious reduction in pain during training. For the PRF group, the placebo was followed by a reduction in pain stimulation on 62.5% of trials only. In the test phase, pain stimulation was equivalent across placebo and no placebo trials. Both continuous and partial reinforcement produced placebo analgesia, with the magnitude of initial analgesia being larger following continuous reinforcement. However, while the placebo analgesia established under continuous reinforcement extinguished during test phase, the placebo analgesia established under partial reinforcement did not. These findings indicate that partial reinforcement can induce placebo analgesia and that these effects are more resistant to extinction than those established via continuous reinforcement. Partial reinforcement may, therefore, reflect a novel way of enhancing clinical outcomes via the placebo effect. PMID:24602997

Anti-scar Treatment for Deep Partial-thickness Burn Wounds

DTIC Science & Technology

2017-10-01

fibrosis will be correlated with scar reduction. 15. SUBJECT TERMS 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT Unclassified 18. NUMBER...treatment will be optimized and molecular markers of inflammation, angiogenesis, wound healing, and fibrosis will be correlated with scar reduction

REDUCTIVE BIOTRANSFORMATION OF TETRACHLOROETHENE TO ETHENE DURING ANAEROBIC DEGRADATION OF TOLUENE: EXPERIMENTAL EVIDENCE AND KINETICS

EPA Science Inventory

Reductive biotransformation of tetrachloroethene (PCE) to ethene occurred during anaerobic degradation of toluene in an enrichment culture. Ethene was detected as a dominant daughter product of PCE dechlorination with negligible accumulation of other partially chlorinated ethenes...

Analysis of E-marketplace Attributes: Assessing The NATO Logistics Stock Exchange

DTIC Science & Technology

2008-01-01

order processing time Reduction of stock levels Reduction of payment processing time Reduction of excessive stocks Reduction of maverick buying...satisfaction 4,02 0,151 3. Reduction of order processing time 4,27 0,317 15. Reduction of stock levels 3,87 0,484 4. Reduction of payment processing time...information exchange with partners in the supply chain Efficiency Basic Reduction of order processing time Efficiency Important Reduction of

Fixed point theorems for generalized contractions in ordered metric spaces

NASA Astrophysics Data System (ADS)

O'Regan, Donal; Petrusel, Adrian

2008-05-01

The purpose of this paper is to present some fixed point results for self-generalized contractions in ordered metric spaces. Our results generalize and extend some recent results of A.C.M. Ran, M.C. Reurings [A.C.M. Ran, MEC. Reurings, A fixed point theorem in partially ordered sets and some applications to matrix equations, Proc. Amer. Math. Soc. 132 (2004) 1435-1443], J.J. Nieto, R. Rodríguez-López [J.J. Nieto, R. Rodríguez-López, Contractive mapping theorems in partially ordered sets and applications to ordinary differential equations, Order 22 (2005) 223-239; J.J. Nieto, R. Rodríguez-López, Existence and uniqueness of fixed points in partially ordered sets and applications to ordinary differential equations, Acta Math. Sin. (Engl. Ser.) 23 (2007) 2205-2212], J.J. Nieto, R.L. Pouso, R. Rodríguez-López [J.J. Nieto, R.L. Pouso, R. Rodríguez-López, Fixed point theorem theorems in ordered abstract sets, Proc. Amer. Math. Soc. 135 (2007) 2505-2517], A. Petrusel, I.A. Rus [A. Petrusel, I.A. Rus, Fixed point theorems in ordered L-spaces, Proc. Amer. Math. Soc. 134 (2006) 411-418] and R.P. Agarwal, M.A. El-Gebeily, D. O'Regan [R.P. Agarwal, M.A. El-Gebeily, D. O'Regan, Generalized contractions in partially ordered metric spaces, Appl. Anal., in press]. As applications, existence and uniqueness results for Fredholm and Volterra type integral equations are given.

Interrelating the breakage and composition of mined and drill core coal

NASA Astrophysics Data System (ADS)

Wilson, Terril Edward

Particle size distribution of coal is important if the coal is to be beneficiated, or if a coal sales contract includes particle size specifications. An exploration bore core sample of coal ought to be reduced from its original cylindrical form to a particle size distribution and particle composition that reflects, insofar as possible, a process stream of raw coal it represents. Often, coal cores are reduced with a laboratory crushing machine, the product of which does not match the raw coal size distribution. This study proceeds from work in coal bore core reduction by Australian investigators. In this study, as differentiated from the Australian work, drop-shatter impact breakage followed by dry batch tumbling in steel cylinder rotated about its transverse axis are employed to characterize the core material in terms of first-order and zeroth-order breakage rate constants, which are indices of the propensity of the coal to degrade during excavation and handling. Initial drop-shatter and dry tumbling calibrations were done with synthetic cores composed of controlled low-strength concrete incorporating fly ash (as a partial substitute for Portland cement) in order to reduce material variables and conserve difficult-to-obtain coal cores. Cores of three different coalbeds--Illinois No. 6, Upper Freeport, and Pocahontas No. 5 were subjected to drop-shatter and dry batch tumbling tests to determine breakage response. First-order breakage, characterized by a first-order breakage index for each coal, occurred in the drop-shatter tests. First- and zeroth-order breakage occurred in dry batch tumbling; disappearance of coarse particles and creation of fine particles occurred in a systematic way that could be represented mathematically. Certain of the coal cores available for testing were dry and friable. Comparison of coal preparation plant feed with a crushed bore core and a bore core prepared by drop-shatter and tumbling (all from the same Illinois No.6 coal mining property) indicated that the size distribution and size fraction composition of the drop-shattered/tumbled core more closely resembled the plant feed than the crushed core. An attempt to determine breakage parameters (to allow use of selection and breakage functions and population balance models in the description of bore core size reduction) was initiated. Rank determination of the three coal types was done, indicating that higher rank associates with higher breakage propensity. The two step procedure of drop-shatter and dry batch tumbling simulates the first-order (volume breakage) and zeroth-order (abrasion of particle surfaces) that occur in excavation and handling operations, and is appropriate for drill core reduction prior to laboratory analysis.

Soft ferromagnetism in mixed valence Sr(1-x)La(x)Ti(0.5)Mn(0.5)O₃ perovskites.

PubMed

Qasim, Ilyas; Blanchard, Peter E R; Kennedy, Brendan J; Ling, Chris D; Jang, Ling-Yun; Kamiyama, Takashi; Miao, Ping; Torii, Shuki

2014-05-14

The structural, magnetic and electrical properties of the mixed Ti-Mn oxides Sr(1-x)La(x)Ti(0.5)Mn(0.5)O3 (0 ≤ x ≤ 0.5) are reported. At room temperature the oxides have a cubic structure in space group Pm3m for x ≤ 0.25 and rhombohedral in R3c for 0.3 ≤ x ≤ 0.50. X-ray absorption spectroscopic measurements demonstrate the addition of La(3+) is compensated by the partial reduction of Mn(4+) to Mn(3+). Variable temperature neutron diffraction measurements show that cooling Sr(0.6)La(0.4)Ti(0.5)Mn(0.5)O3 results in a first order transition from rhombohedra to an orthorhombic structure in Imma. Complex magnetic behaviour is observed. The magnetic behaviour of the mixed valent (Mn(3+/4+)) examples is dominated by ferromagnetic interactions, although cation disorder frustrates long range magnetic ordering.

Study on biphasic material model and mechanical analysis of knee joint cartilage

NASA Astrophysics Data System (ADS)

Nakatani, A.; Sakashita, A.

2008-02-01

A material model of articular cartilage is formulated, and fundamental problems are analyzed. The soft tissue is assumed to comprise two phases: solid and fluid. The biphasic theory proposed by Spilker and Suh (1990) to deal with such materials is reviewed, and some new additional analyses are carried out on the basis of this theory. Assuming the elasticity for the solid phase and introducing the pressure, which is defined by the product of the volume change and penalty coefficient, it is shown that the viscoelastic property of the soft tissue can be reproduced. A preferable solution is obtained for the solid phase by using the reduction integral, even if a high-order interpolation function is used. However, the high-order element cannot satisfactorily capture the velocity distribution of fluids. The pressure distribution is studied by assuming the change in the surface characteristics of the cartilage tissue with the progress of osteoarthritis. The pressure is strongly related to the lubrication conditions, i.e., perfect lubrication, perfect adhesion, and partial adhesion.

A high order accurate finite element algorithm for high Reynolds number flow prediction

NASA Technical Reports Server (NTRS)

Baker, A. J.

1978-01-01

A Galerkin-weighted residuals formulation is employed to establish an implicit finite element solution algorithm for generally nonlinear initial-boundary value problems. Solution accuracy, and convergence rate with discretization refinement, are quantized in several error norms, by a systematic study of numerical solutions to several nonlinear parabolic and a hyperbolic partial differential equation characteristic of the equations governing fluid flows. Solutions are generated using selective linear, quadratic and cubic basis functions. Richardson extrapolation is employed to generate a higher-order accurate solution to facilitate isolation of truncation error in all norms. Extension of the mathematical theory underlying accuracy and convergence concepts for linear elliptic equations is predicted for equations characteristic of laminar and turbulent fluid flows at nonmodest Reynolds number. The nondiagonal initial-value matrix structure introduced by the finite element theory is determined intrinsic to improved solution accuracy and convergence. A factored Jacobian iteration algorithm is derived and evaluated to yield a consequential reduction in both computer storage and execution CPU requirements while retaining solution accuracy.

Vibration reduction in helicopter rotors using an actively controlled partial span trailing edge flap located on the blade

NASA Technical Reports Server (NTRS)

Millott, T. A.; Friedmann, P. P.

1994-01-01

This report describes an analytical study of vibration reduction in a four-bladed helicopter rotor using an actively controlled, partial span, trailing edge flap located on the blade. The vibration reduction produced by the actively controlled flap (ACF) is compared with that obtained using individual blade control (IBC), in which the entire blade is oscillated in pitch. For both cases a deterministic feedback controller is implemented to reduce the 4/rev hub loads. For all cases considered, the ACF produced vibration reduction comparable with that obtained using IBC, but consumed only 10-30% of the power required to implement IBC. A careful parametric study is conducted to determine the influence of blade torsional stiffness, spanwise location of the control flap, and hinge moment correction on the vibration reduction characteristics of the ACF. The results clearly demonstrate the feasibility of this new approach to vibration reduction. It should be emphasized than the ACF, used together with a conventional swashplate, is completely decoupled from the primary flight control system and thus it has no influence on the airworthiness of the helicopter. This attribute is potentially a significant advantage when compared to IBC.

Randomized controlled trial of zonisamide for the treatment of refractory partial-onset seizures.

PubMed

Faught, E; Ayala, R; Montouris, G G; Leppik, I E

2001-11-27

Zonisamide is a sulfonamide antiepilepsy drug with sodium and calcium channel-blocking actions. Experience in Japan and a previous European double-blind study have demonstrated its efficacy against partial-onset seizures. A randomized, double-blind, placebo-controlled trial enrolling 203 patients was conducted at 20 United States sites to assess zonisamide efficacy and dose response as adjunctive therapy for refractory partial-onset seizures. Zonisamide dosages were elevated by 100 mg/d each week. The study design allowed parallel comparisons with placebo for three dosages and a final crossover to 400 mg/d of zonisamide for all patients. The primary efficacy comparison was change in seizure frequency from a 4-week placebo baseline to weeks 8 through 12 on blinded therapy. At 400 mg/d, zonisamide reduced the median frequency of all seizures by 40.5% from baseline, compared with a 9% reduction (p = 0.0009) with placebo treatment, and produced a > or =50% seizure reduction (responder rate) in 42% of patients. A dosage of 100 mg/d produced a 20.5% reduction in median seizure frequency (p = 0.038 compared with placebo) and a dosage of 200 mg/d produced a 24.7% reduction in median seizure frequency (p = 0.004 compared with placebo). Dropouts from adverse events (10%) did not differ from placebo (8.2%, NS). The only adverse event differing significantly from placebo was weight loss, though somnolence, anorexia, and ataxia were slightly more common with zonisamide treatment. Serum zonisamide concentrations rose with increasing dose. Zonisamide is effective and well tolerated as an adjunctive agent for refractory partial-onset seizures. The minimal effective dosage was 100 mg/d, but 400 mg/d was the most effective dosage.

Specifications of a continual reassessment method design for phase I trials of combined drugs†

PubMed Central

Wages, Nolan A.; Conaway, Mark R.

2013-01-01

In studies of combinations of agents in phase I oncology trials, the dose–toxicity relationship may not be monotone for all combinations, in which case the toxicity probabilities follow a partial order. The continual reassessment method for partial orders (PO-CRM) is a design for phase I trials of combinations that leans upon identifying possible complete orders associated with the partial order. This article addresses some practical design considerations not previously undertaken when describing the PO-CRM. We describe an approach in choosing a proper subset of possible orderings, formulated according to the known toxicity relationships within a matrix of combination therapies. Other design issues, such as working model selection and stopping rules, are also discussed. We demonstrate the practical ability of PO-CRM as a phase I design for combinations through its use in a recent trial designed at the University of Virginia Cancer Center. PMID:23729323

Scintillation and bit error rate analysis of a phase-locked partially coherent flat-topped array laser beam in oceanic turbulence.

PubMed

Yousefi, Masoud; Kashani, Fatemeh Dabbagh; Golmohammady, Shole; Mashal, Ahmad

2017-12-01

In this paper, the performance of underwater wireless optical communication (UWOC) links, which is made up of the partially coherent flat-topped (PCFT) array laser beam, has been investigated in detail. Providing high power, array laser beams are employed to increase the range of UWOC links. For characterization of the effects of oceanic turbulence on the propagation behavior of the considered beam, using the extended Huygens-Fresnel principle, an analytical expression for cross-spectral density matrix elements and a semi-analytical one for fourth-order statistical moment have been derived. Then, based on these expressions, the on-axis scintillation index of the mentioned beam propagating through weak oceanic turbulence has been calculated. Furthermore, in order to quantify the performance of the UWOC link, the average bit error rate (BER) has also been evaluated. The effects of some source factors and turbulent ocean parameters on the propagation behavior of the scintillation index and the BER have been studied in detail. The results of this investigation indicate that in comparison with the Gaussian array beam, when the source size of beamlets is larger than the first Fresnel zone, the PCFT array laser beam with the higher flatness order is found to have a lower scintillation index and hence lower BER. Specifically, in the sense of scintillation index reduction, using the PCFT array laser beams has a considerable benefit in comparison with the single PCFT or Gaussian laser beams and also Gaussian array beams. All the simulation results of this paper have been shown by graphs and they have been analyzed in detail.

Latent Partially Ordered Classification Models and Normal Mixtures

ERIC Educational Resources Information Center

Tatsuoka, Curtis; Varadi, Ferenc; Jaeger, Judith

2013-01-01

Latent partially ordered sets (posets) can be employed in modeling cognitive functioning, such as in the analysis of neuropsychological (NP) and educational test data. Posets are cognitively diagnostic in the sense that classification states in these models are associated with detailed profiles of cognitive functioning. These profiles allow for…

77 FR 53226 - Public Land Order No. 7792; Partial Revocation, Power Site Reserve No. 109; Montana

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-31

... DEPARTMENT OF THE INTERIOR Bureau of Land Management [MT-LLB05000-LL14300000-FQ0000; MTM 40412] Public Land Order No. 7792; Partial Revocation, Power Site Reserve No. 109; Montana Correction In notice...:45 am] BILLING CODE 1505-01-D ...

76 FR 24513 - Public Land Order No. 7765; Partial Revocation Jupiter Inlet Lighthouse Withdrawal; Florida

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-02

...] Public Land Order No. 7765; Partial Revocation Jupiter Inlet Lighthouse Withdrawal; Florida AGENCY... as part of the Jupiter Inlet Lighthouse Outstanding Natural Area. DATES: Effective Date: May 2, 2011... U.S.C. 1787), which created the Jupiter Inlet Lighthouse Outstanding Natural Area, and which...

On the hierarchy of partially invariant submodels of differential equations

NASA Astrophysics Data System (ADS)

Golovin, Sergey V.

2008-07-01

It is noted that the partially invariant solution (PIS) of differential equations in many cases can be represented as an invariant reduction of some PISs of the higher rank. This introduces a hierarchic structure in the set of all PISs of a given system of differential equations. An equivalence of the two-step and the direct ways of construction of PISs is proved. The hierarchy simplifies the process of enumeration and analysis of partially invariant submodels to the given system of differential equations. In this framework, the complete classification of regular partially invariant solutions of ideal MHD equations is given.

Scalable Replay with Partial-Order Dependencies for Message-Logging Fault Tolerance

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

Lifflander, Jonathan; Meneses, Esteban; Menon, Harshita

2014-09-22

Deterministic replay of a parallel application is commonly used for discovering bugs or to recover from a hard fault with message-logging fault tolerance. For message passing programs, a major source of overhead during forward execution is recording the order in which messages are sent and received. During replay, this ordering must be used to deterministically reproduce the execution. Previous work in replay algorithms often makes minimal assumptions about the programming model and application in order to maintain generality. However, in many cases, only a partial order must be recorded due to determinism intrinsic in the code, ordering constraints imposed bymore » the execution model, and events that are commutative (their relative execution order during replay does not need to be reproduced exactly). In this paper, we present a novel algebraic framework for reasoning about the minimum dependencies required to represent the partial order for different concurrent orderings and interleavings. By exploiting this theory, we improve on an existing scalable message-logging fault tolerance scheme. The improved scheme scales to 131,072 cores on an IBM BlueGene/P with up to 2x lower overhead than one that records a total order.« less

Some New Sets of Sequences of Fuzzy Numbers with Respect to the Partial Metric

PubMed Central

Ozluk, Muharrem

2015-01-01

In this paper, we essentially deal with Köthe-Toeplitz duals of fuzzy level sets defined using a partial metric. Since the utilization of Zadeh's extension principle is quite difficult in practice, we prefer the idea of level sets in order to construct some classical notions. In this paper, we present the sets of bounded, convergent, and null series and the set of sequences of bounded variation of fuzzy level sets, based on the partial metric. We examine the relationships between these sets and their classical forms and give some properties including definitions, propositions, and various kinds of partial metric spaces of fuzzy level sets. Furthermore, we study some of their properties like completeness and duality. Finally, we obtain the Köthe-Toeplitz duals of fuzzy level sets with respect to the partial metric based on a partial ordering. PMID:25695102

48 CFR 970.3200-1 - Reduction or suspension of advance, partial, or progress payments.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Reduction or suspension of... System DEPARTMENT OF ENERGY AGENCY SUPPLEMENTARY REGULATIONS DOE MANAGEMENT AND OPERATING CONTRACTS... receiving, assessing, and making recommendations to the Senior Procurement Executive. ...

Partially oxidized iridium clusters within dendrimers: size-controlled synthesis and selective hydrogenation of 2-nitrobenzaldehyde

NASA Astrophysics Data System (ADS)

Higaki, Tatsuya; Kitazawa, Hirokazu; Yamazoe, Seiji; Tsukuda, Tatsuya

2016-06-01

Iridium clusters nominally composed of 15, 30 or 60 atoms were size-selectively synthesized within OH-terminated poly(amidoamine) dendrimers of generation 6. Spectroscopic characterization revealed that the Ir clusters were partially oxidized. All the Ir clusters efficiently converted 2-nitrobenzaldehyde to anthranil and 2-aminobenzaldehyde under atmospheric hydrogen at room temperature in toluene via selective hydrogenation of the NO2 group. The selectivity toward 2-aminobenzaldehyde over anthranil was improved with the reduction of the cluster size. The improved selectivity is ascribed to more efficient reduction than intramolecular heterocyclization of a hydroxylamine intermediate on smaller clusters that have a higher Ir(0)-phase population on the surface.Iridium clusters nominally composed of 15, 30 or 60 atoms were size-selectively synthesized within OH-terminated poly(amidoamine) dendrimers of generation 6. Spectroscopic characterization revealed that the Ir clusters were partially oxidized. All the Ir clusters efficiently converted 2-nitrobenzaldehyde to anthranil and 2-aminobenzaldehyde under atmospheric hydrogen at room temperature in toluene via selective hydrogenation of the NO2 group. The selectivity toward 2-aminobenzaldehyde over anthranil was improved with the reduction of the cluster size. The improved selectivity is ascribed to more efficient reduction than intramolecular heterocyclization of a hydroxylamine intermediate on smaller clusters that have a higher Ir(0)-phase population on the surface. Electronic supplementary information (ESI) available. See DOI: 10.1039/c6nr01460g

Theoretical study of the partial molar volume change associated with the pressure-induced structural transition of ubiquitin

PubMed Central

Imai, Takashi; Ohyama, Shusaku; Kovalenko, Andriy; Hirata, Fumio

2007-01-01

The partial molar volume (PMV) change associated with the pressure-induced structural transition of ubiquitin is analyzed by the three-dimensional reference interaction site model (3D-RISM) theory of molecular solvation. The theory predicts that the PMV decreases upon the structural transition, which is consistent with the experimental observation. The volume decomposition analysis demonstrates that the PMV reduction is primarily caused by the decrease in the volume of structural voids in the protein, which is partially canceled by the volume expansion due to the hydration effects. It is found from further analysis that the PMV reduction is ascribed substantially to the penetration of water molecules into a specific part of the protein. Based on the thermodynamic relation, this result implies that the water penetration causes the pressure-induced structural transition. It supports the water penetration model of pressure denaturation of proteins proposed earlier. PMID:17660257

Theoretical study of the partial molar volume change associated with the pressure-induced structural transition of ubiquitin.

PubMed

Imai, Takashi; Ohyama, Shusaku; Kovalenko, Andriy; Hirata, Fumio

2007-09-01

The partial molar volume (PMV) change associated with the pressure-induced structural transition of ubiquitin is analyzed by the three-dimensional reference interaction site model (3D-RISM) theory of molecular solvation. The theory predicts that the PMV decreases upon the structural transition, which is consistent with the experimental observation. The volume decomposition analysis demonstrates that the PMV reduction is primarily caused by the decrease in the volume of structural voids in the protein, which is partially canceled by the volume expansion due to the hydration effects. It is found from further analysis that the PMV reduction is ascribed substantially to the penetration of water molecules into a specific part of the protein. Based on the thermodynamic relation, this result implies that the water penetration causes the pressure-induced structural transition. It supports the water penetration model of pressure denaturation of proteins proposed earlier.

Invariant and partially-invariant solutions of the equations describing a non-stationary and isentropic flow for an ideal and compressible fluid in (3 + 1) dimensions

NASA Astrophysics Data System (ADS)

Grundland, A. M.; Lalague, L.

1996-04-01

This paper presents a new method of constructing, certain classes of solutions of a system of partial differential equations (PDEs) describing the non-stationary and isentropic flow for an ideal compressible fluid. A generalization of the symmetry reduction method to the case of partially-invariant solutions (PISs) has been formulated. We present a new algorithm for constructing PISs and discuss in detail the necessary conditions for the existence of non-reducible PISs. All these solutions have the defect structure 0305-4470/29/8/019/img1 and are computed from four-dimensional symmetric subalgebras. These theoretical considerations are illustrated by several examples. Finally, some new classes of invariant solutions obtained by the symmetry reduction method are included. These solutions represent central, conical, rational, spherical, cylindrical and non-scattering double waves.

A reduction of diffusion in PVA Fricke hydrogels

NASA Astrophysics Data System (ADS)

Smith, S. T.; Masters, K. S.; Hosokawa, K.; Blinco, J.; Crowe, S. B.; Kairn, T.; Trapp, J. V.

2015-01-01

A modification to the PVA-FX hydrogel whereby the chelating agent, xylenol orange, was partially bonded to the gelling agent, poly-vinyl alcohol, resulted in an 8% reduction in the post irradiation Fe3+ diffusion, adding approximately 1 hour to the useful timespan between irradiation and readout. This xylenol orange functionalised poly-vinyl alcohol hydrogel had an OD dose sensitivity of 0.014 Gy-1 and a diffusion rate of 0.133 mm2 h-1. As this partial bond yields only incremental improvement, it is proposed that more efficient methods of bonding xylenol orange to poly-vinyl alcohol be investigated to further reduce the diffusion in Fricke gels.

Chiral copper(II) complex-catalyzed reactions of partially protected carbohydrates.

PubMed

Allen, C Liana; Miller, Scott J

2013-12-20

Catalyst-controlled regioselective functionalization of partially protected saccharide molecules is a highly important yet under-developed area of carbohydrate chemistry. Such reactions allow for the reduction of protecting group manipulation steps required in syntheses involving sugars. Herein, an approach to these processes using enantiopure copper-bis(oxazoline) catalysts to control couplings of electrophiles to various partially protected sugars is reported. In a number of cases, divergent regioselectivity was observed as a function of the enantiomer of catalyst that is used.

Anaerobic digestion of sulfate-acidified cattle slurry: One-stage vs. two-stage.

PubMed

Moset, Veronica; Ottosen, Lars Ditlev Mørck; Xavier, Cristiane de Almeida Neves; Møller, Henrik Bjarne

2016-05-15

Two strategies to include acidified cattle manure (AcCM) in co-digestion with normal cattle manure (CM) are presented in this work. The strategies are a single thermophilic (50 °C) continuous stirred tank reactor (CSTR) anaerobic digestion and a two-step (65 °C + 50 °C) CSTR process. In both strategies, two different inclusion levels of H2SO4-acidified CM (10% and 20%) in co-digestion with normal CM were tested and compared with a control CSTR fed only CM. Important enhancement of methane (CH4) yield and solid reductions were observed in the thermophilic one-step CSTR working with 10% AcCM. However, a higher inclusion level of AcCM (20%) caused volatile fatty acid accumulation in the reactor and a more than 30% reduction in CH4 production. In terms of CH4 production, when 10% of AcCM was co-digested with 90% of CM, the two-step anaerobic co-digestion yielded less than the single step. During the first step of the two-step CSTR process, acidogenesis and a partial sulfate reduction were achieved. However, sulfide stripping between the first and the second step must be promoted in order to advance this technology. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effect of different promoter precursors in a model Ru-Cs/graphite system on the catalytic selectivity for Fischer-Tropsch reaction

NASA Astrophysics Data System (ADS)

Eslava, José L.; Iglesias-Juez, Ana; Fernández-García, Marcos; Guerrero-Ruiz, Antonio; Rodríguez-Ramos, Inmaculada

2018-07-01

The effect of using two different promoter precursors on the Fischer-Tropsch synthesis was studied over cesium promoted ruthenium catalysts supported on a high surface area graphite support. In this work we reveal significant modifications in the selectivity values for Fischer-Tropsch reaction depending on the Cs promoter precursor (CsCl vs CsNO3). Specifically the bimetallic catalyst (4Ru-4Cs), prepared from nitrates both for metal and promoter precursors, showed a high selectivity to CO2 during reaction. By modifying the cesium precursor, it was possible to inhibit the water gas shift reaction, decreasing significantly the selectivity to CO2. In order to understand the chemical origin of these modifications a careful characterization of the materials was performed including: X-ray absorption near edge spectroscopy, transmission electron microscopy measurements, temperature programmed reduction studies, determination of the CO uptakes on the catalysts and the evolution of the CO adsorption heats as a function of surface coverages. It was found that upon reduction and under reaction atmosphere the promoter in the ex-nitrate catalyst appears as Cs2O which is considered responsible of the CO2 production, while in the catalysts prepared with Cs chloride the promoter remains as CsCl suffering a slight partial reduction.

Bacterial carbonate precipitation improves water absorption of interlocking compressed earth block (ICEB)

NASA Astrophysics Data System (ADS)

Zamer, M. M.; Irwan, J. M.; Othman, N.; Faisal, S. K.; Anneza, L. H.; Alshalif, A. F.; Teddy, T.

2017-11-01

Interlocking compressed earth blocks (ICEB) are soil based blocks that allows for mortarless construction. The addition of many alternative materials into interlocking block in order to improve the durability has been reported. However there are currently lack of report and evidence on the application of biocalcification or microbiologically induced calcite precipitation (MICP) in improving the engineering properties of ICEB. This paper evaluate the effect of UB in improving the water absorption properties of ICEB. This paper also provide the results on SEM analysis of addition of 1%, 3% and 5% UB in ICEB. The bacteria were added as partial replacement of limestone water in ICEB. The results showed the reduction of 14.72% with 5% UB on initial water absorption followed by the results for water absorption by 24-hour soaking which also indicates reduction of 14.68% with 5% UB on 28th days of testing compared to control specimen. It was expected that the reduction of water absorption was due to the plugging of pores by the bacterial calcite which prevent ingression of water in ICEB samples. Therefore this study hopes that the positive results from the UB as improving in water absorption of ICEB will lead to improve others ICEB properties and others construction materials.

Kinematic sensitivity of robot manipulators

NASA Technical Reports Server (NTRS)

Vuskovic, Marko I.

1989-01-01

Kinematic sensitivity vectors and matrices for open-loop, n degrees-of-freedom manipulators are derived. First-order sensitivity vectors are defined as partial derivatives of the manipulator's position and orientation with respect to its geometrical parameters. The four-parameter kinematic model is considered, as well as the five-parameter model in case of nominally parallel joint axes. Sensitivity vectors are expressed in terms of coordinate axes of manipulator frames. Second-order sensitivity vectors, the partial derivatives of first-order sensitivity vectors, are also considered. It is shown that second-order sensitivity vectors can be expressed as vector products of the first-order sensitivity vectors.

Semiantichains and Unichain Coverings in Direct Products of Partial Orders.

DTIC Science & Technology

1980-09-01

34 Discrete Math . 5 (1973), 305-337. 13) G. B. Dantsig and A. J. 11offman, "Dilworth’s theorem on partially ordered sets,* in Linear Inequalities and Related...Sperner theorem,* Discrete Math . 17 (1977), 281-289. 118) A. J. Hoffman, ’The role of unimodularity in applying linear inequalities to combinatorial

Estimation in SEM: A Concrete Example

ERIC Educational Resources Information Center

Ferron, John M.; Hess, Melinda R.

2007-01-01

A concrete example is used to illustrate maximum likelihood estimation of a structural equation model with two unknown parameters. The fitting function is found for the example, as are the vector of first-order partial derivatives, the matrix of second-order partial derivatives, and the estimates obtained from each iteration of the Newton-Raphson…

Generalized Second-Order Partial Derivatives of 1/r

ERIC Educational Resources Information Center

Hnizdo, V.

2011-01-01

The generalized second-order partial derivatives of 1/r, where r is the radial distance in three dimensions (3D), are obtained using a result of the potential theory of classical analysis. Some non-spherical-regularization alternatives to the standard spherical-regularization expression for the derivatives are derived. The utility of a…

On-the-fly scheduling as a manifestation of partial-order planning and dynamic task values.

PubMed

Hannah, Samuel D; Neal, Andrew

2014-09-01

The aim of this study was to develop a computational account of the spontaneous task ordering that occurs within jobs as work unfolds ("on-the-fly task scheduling"). Air traffic control is an example of work in which operators have to schedule their tasks as a partially predictable work flow emerges. To date, little attention has been paid to such on-the-fly scheduling situations. We present a series of discrete-event models fit to conflict resolution decision data collected from experienced controllers operating in a high-fidelity simulation. Our simulations reveal air traffic controllers' scheduling decisions as examples of the partial-order planning approach of Hayes-Roth and Hayes-Roth. The most successful model uses opportunistic first-come-first-served scheduling to select tasks from a queue. Tasks with short deadlines are executed immediately. Tasks with long deadlines are evaluated to assess whether they need to be executed immediately or deferred. On-the-fly task scheduling is computationally tractable despite its surface complexity and understandable as an example of both the partial-order planning strategy and the dynamic-value approach to prioritization.

CSI Feedback Reduction for MIMO Interference Alignment

NASA Astrophysics Data System (ADS)

Rao, Xiongbin; Ruan, Liangzhong; Lau, Vincent K. N.

2013-09-01

Interference alignment (IA) is a linear precoding strategy that can achieve optimal capacity scaling at high SNR in interference networks. Most of the existing IA designs require full channel state information (CSI) at the transmitters, which induces a huge CSI signaling cost. Hence it is desirable to improve the feedback efficiency for IA and in this paper, we propose a novel IA scheme with a significantly reduced CSI feedback. To quantify the CSI feedback cost, we introduce a novel metric, namely the feedback dimension. This metric serves as a first-order measurement of CSI feedback overhead. Due to the partial CSI feedback constraint, conventional IA schemes can not be applied and hence, we develop a novel IA precoder / decorrelator design and establish new IA feasibility conditions. Via dynamic feedback profile design, the proposed IA scheme can also achieve a flexible tradeoff between the degree of freedom (DoF) requirements for data streams, the antenna resources and the CSI feedback cost. We show by analysis and simulations that the proposed scheme achieves substantial reductions of CSI feedback overhead under the same DoF requirement in MIMO interference networks.

BH3-Only Molecule Bim Mediates β-Cell Death in IRS2 Deficiency

PubMed Central

Ren, Decheng; Sun, Juan; Mao, Liqun; Ye, Honggang

2014-01-01

Irs2-deficient mice develop type 2–like diabetes due to a reduction in β-cell mass and a failure of pancreatic islets to undergo compensatory hyperplasia in response to insulin resistance. In order to define the molecular mechanisms, we knocked down Irs2 gene expression in mouse MIN6 insulinoma cells. Insulin receptor substrate 2 (IRS2) suppression induced apoptotic cell death, which was associated with an increase in expression of the BH3-only molecule Bim. Knockdown (KD) of Bim reduced apoptotic β-cell death induced by IRS2 suppression. In Irs2-deficient mice, Bim ablation restored β-cell mass, decreased the number of TUNEL-positive cells, and restored normal glucose tolerance after glucose challenge. FoxO1 mediates Bim upregulation induced by IRS2 suppression, and FoxO1 KD partially inhibits β-cell death induced by IRS2 suppression. These results suggest that Bim plays an important role in mediating the increase in β-cell apoptosis and the reduction in β-cell mass that occurs in IRS2-deficient diabetes. PMID:24760140

Coupled s-p-d Exchange in Facet-Controlled Pd 3 Pb Tripods Enhances Oxygen Reduction Catalysis

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

Bu, Lingzheng; Shao, Qi; Pi, Yecan

Efficient oxygen reduction reaction (ORR) catalysts are the key in developing high-performance fuel cells. Palladium (Pd) is a promising catalyst system for ORR with its potential to replace platinum (Pt), however it usually exhibits lower activity than Pt. Herein, we report a class of ordered Pd3Pb tripods (TPs) with dominated {110} facets that show extremely high ORR performance in alkaline medium. Totally different from the well-known knowledge that excellent ORR activity of Pt catalyst is caused by its partially-filled d-orbital, our first principle calculations suggest that the strong charge exchange between Pd-4d and Pb-(sp) orbitals on Pd3Pb TPs {110} facetmore » results in the Pd-Pb local bonding unit with the orbital configuration similar to Pt. Consequently, the Pd3Pb TPs exhibit much higher ORR activities than commercial Pt/C and commercial Pd/C. The Pd3Pb TPs are rather endurable and sustain over 20,000 potential cycles with negligible structural and compositional changes.« less

Coupled s-p-d Exchange in Facet-Controlled Pd 3 Pb Tripods Enhances Oxygen Reduction Catalysis

DOE PAGES

Bu, Lingzheng; Shao, Qi; Pi, Yecan; ...

2018-02-01

Efficient oxygen reduction reaction (ORR) catalysts are the key in developing high-performance fuel cells. Palladium (Pd) is a promising catalyst system for ORR with its potential to replace platinum (Pt), however it usually exhibits lower activity than Pt. Herein, we report a class of ordered Pd3Pb tripods (TPs) with dominated {110} facets that show extremely high ORR performance in alkaline medium. Totally different from the well-known knowledge that excellent ORR activity of Pt catalyst is caused by its partially-filled d-orbital, our first principle calculations suggest that the strong charge exchange between Pd-4d and Pb-(sp) orbitals on Pd3Pb TPs {110} facetmore » results in the Pd-Pb local bonding unit with the orbital configuration similar to Pt. Consequently, the Pd3Pb TPs exhibit much higher ORR activities than commercial Pt/C and commercial Pd/C. The Pd3Pb TPs are rather endurable and sustain over 20,000 potential cycles with negligible structural and compositional changes.« less

Lattice Boltzmann model for high-order nonlinear partial differential equations

NASA Astrophysics Data System (ADS)

Chai, Zhenhua; He, Nanzhong; Guo, Zhaoli; Shi, Baochang

2018-01-01

In this paper, a general lattice Boltzmann (LB) model is proposed for the high-order nonlinear partial differential equation with the form ∂tϕ +∑k=1mαk∂xkΠk(ϕ ) =0 (1 ≤k ≤m ≤6 ), αk are constant coefficients, Πk(ϕ ) are some known differential functions of ϕ . As some special cases of the high-order nonlinear partial differential equation, the classical (m)KdV equation, KdV-Burgers equation, K (n ,n ) -Burgers equation, Kuramoto-Sivashinsky equation, and Kawahara equation can be solved by the present LB model. Compared to the available LB models, the most distinct characteristic of the present model is to introduce some suitable auxiliary moments such that the correct moments of equilibrium distribution function can be achieved. In addition, we also conducted a detailed Chapman-Enskog analysis, and found that the high-order nonlinear partial differential equation can be correctly recovered from the proposed LB model. Finally, a large number of simulations are performed, and it is found that the numerical results agree with the analytical solutions, and usually the present model is also more accurate than the existing LB models [H. Lai and C. Ma, Sci. China Ser. G 52, 1053 (2009), 10.1007/s11433-009-0149-3; H. Lai and C. Ma, Phys. A (Amsterdam) 388, 1405 (2009), 10.1016/j.physa.2009.01.005] for high-order nonlinear partial differential equations.

Lattice Boltzmann model for high-order nonlinear partial differential equations.

PubMed

Chai, Zhenhua; He, Nanzhong; Guo, Zhaoli; Shi, Baochang

2018-01-01

In this paper, a general lattice Boltzmann (LB) model is proposed for the high-order nonlinear partial differential equation with the form ∂_{t}ϕ+∑_{k=1}^{m}α_{k}∂_{x}^{k}Π_{k}(ϕ)=0 (1≤k≤m≤6), α_{k} are constant coefficients, Π_{k}(ϕ) are some known differential functions of ϕ. As some special cases of the high-order nonlinear partial differential equation, the classical (m)KdV equation, KdV-Burgers equation, K(n,n)-Burgers equation, Kuramoto-Sivashinsky equation, and Kawahara equation can be solved by the present LB model. Compared to the available LB models, the most distinct characteristic of the present model is to introduce some suitable auxiliary moments such that the correct moments of equilibrium distribution function can be achieved. In addition, we also conducted a detailed Chapman-Enskog analysis, and found that the high-order nonlinear partial differential equation can be correctly recovered from the proposed LB model. Finally, a large number of simulations are performed, and it is found that the numerical results agree with the analytical solutions, and usually the present model is also more accurate than the existing LB models [H. Lai and C. Ma, Sci. China Ser. G 52, 1053 (2009)1672-179910.1007/s11433-009-0149-3; H. Lai and C. Ma, Phys. A (Amsterdam) 388, 1405 (2009)PHYADX0378-437110.1016/j.physa.2009.01.005] for high-order nonlinear partial differential equations.

Force Reduction Impacts on Resourcing Army Operational Requirements

DTIC Science & Technology

2017-03-10

scenarios involving parametric changes to demand for and supply of manpower and equipment from the institutional Army. This type of mission- based ...i SPECIAL REPORT Force Reduction Impacts on Resourcing Army Operational Requirements By Dynamics Research Corporation In Partial... Research .................................................................................................. 12 2.1.2 Identifying and Collecting Unit

Noise reduction in digital lensless holographic microscopy by engineering the light from a light-emitting diode.

PubMed

Garcia-Sucerquia, Jorge

2013-01-01

By engineering the light from a light-emitting diode (LED) the noises present in digital lensless holographic microscopy (DLHM) are reduced. The partially coherent light from an LED is tailored to produce a spherical wavefront with limited coherence time and the spatial coherence needed by DLHM to work. DLHM with this engineered light source is used to image biological samples that cover areas of the order of mm(2). The ratio between the diameter of the area that is almost coherently illuminated to the diameter of the illumination area is utilized as parameter to quantify the performance of the DLHM with the engineered LED light source. Experimental results show that while the noises can be reduced effectively the spatial resolution can be kept in the micrometer range.

Polyaniline-grafted reduced graphene oxide for efficient electrochemical supercapacitors.

PubMed

Kumar, Nanjundan Ashok; Choi, Hyun-Jung; Shin, Yeon Ran; Chang, Dong Wook; Dai, Liming; Baek, Jong-Beom

2012-02-28

An alternative and effective route to prepare conducting polyaniline-grafted reduced graphene oxide (PANi-g-rGO) composite with highly enhanced properties is reported. In order to prepare PANi-g-rGO, amine-protected 4-aminophenol was initially grafted to graphite oxide (GO) via acyl chemistry where a concomitant partial reduction of GO occurred due to the refluxing and exposure of GO to thionyl chloride vapors and heating. Following the deprotection of amine groups, an in situ chemical oxidative grafting of aniline in the presence of an oxidizing agent was carried out to yield highly conducting PANi-g-rGO. Electron microscopic studies demonstrated that the resultant composite has fibrillar morphology with a room-temperature electrical conductivity as high as 8.66 S/cm and capacitance of 250 F/g with good cycling stability.

Software Model Checking of ARINC-653 Flight Code with MCP

NASA Technical Reports Server (NTRS)

Thompson, Sarah J.; Brat, Guillaume; Venet, Arnaud

2010-01-01

The ARINC-653 standard defines a common interface for Integrated Modular Avionics (IMA) code. In particular, ARINC-653 Part 1 specifies a process- and partition-management API that is analogous to POSIX threads, but with certain extensions and restrictions intended to support the implementation of high reliability flight code. MCP is a software model checker, developed at NASA Ames, that provides capabilities for model checking C and C++ source code. In this paper, we present recent work aimed at implementing extensions to MCP that support ARINC-653, and we discuss the challenges and opportunities that consequentially arise. Providing support for ARINC-653 s time and space partitioning is nontrivial, though there are implicit benefits for partial order reduction possible as a consequence of the API s strict interprocess communication policy.

Generation of linear dynamic models from a digital nonlinear simulation

NASA Technical Reports Server (NTRS)

Daniele, C. J.; Krosel, S. M.

1979-01-01

The results and methodology used to derive linear models from a nonlinear simulation are presented. It is shown that averaged positive and negative perturbations in the state variables can reduce numerical errors in finite difference, partial derivative approximations and, in the control inputs, can better approximate the system response in both directions about the operating point. Both explicit and implicit formulations are addressed. Linear models are derived for the F 100 engine, and comparisons of transients are made with the nonlinear simulation. The problem of startup transients in the nonlinear simulation in making these comparisons is addressed. Also, reduction of the linear models is investigated using the modal and normal techniques. Reduced-order models of the F 100 are derived and compared with the full-state models.

[The comparative analysis of clinical symptomatology before and after the operation of otosclerosis].

PubMed

Terzić, Negra; Zivić, Ljubica

2009-01-01

Otosclerosis is a progressive osteodystrophic disease of the osseous capsule of the labyrinth which leads to the fixation of the stapes and partial deafness. The progressive hearing loss followed by ear tingling--tinitus and vertigo is of great importance for this disease. The aim of the work was to determine the changes of clinical symptomatology before and after the operative treatment of otoscleoris. The study included 32 subjects between 25 and 60 years of age affected by otosclerosis who had undergone surgical treatment at the VMA (Military Medical Academy) Clinic, Department of Otolaryngology in Belgrade. Besides the clinical examination and detailed case history, audiometry and tympanometry examinations were performed. During the postoperative period the clinical symptomatology was evaluated and audiometry examinations were performed in order to determine the effect of the surgical intervention. Of the total number of 32 subjects, partial deafness was present in all of them before the operation, whereas tinitus, vertiginous disturbances and otalgia were found in a certain number of the subjects. During the postoperative period a partial recovery was found in a larger number of the subjects in relation to the total hearing recovery. During the postoperative period tinitus of lower intensity was found in a greater number of the subjects, whereas the number of those without tinitus was smaller. The problem of vertiginous disturbances as well as otalgia were not found during the postoperative period. By following the changes of the clinical symptomatology we came to the conclusion that surgical treatment of otosclerosis results in the reduction and disappearance of subjective disturbances, tinitus, vertigo and otalgia and leads to the partial or complete hearing recovery.

Separation behavior of octadecadienoic acid isomers and identification of cis- and trans-isomers using gas chromatography.

PubMed

Shibamoto, Shigeaki; Gooley, Andrew; Yamamoto, Kouhei

2015-01-01

Using a strongly polar cyanopropyl capillary column we have investigated the gas chromatography (GC) separation behaviors of 24 octadecadienoic acid methyl ester (18:2ME) isomers compared against saturated methyl stearate (18:0ME) and arachidic acid methyl ester (20:0ME), and the dependency on the GC column temperature. The 24 isomers were obtained by performing cis-to trans-isomerization of six regioisomers: five of the 18:2ME isomers were prepared by the partial reduction of methyl α-linolenate and methyl γ-linolenate C18 trienoic acids with different double bond positions, whereas the sixth isomer, 18:2ME (c5, c9), was obtained from a raw constituent fatty acid methyl ester (FAME) sample extracted from Japanese yew seeds. There are no reference standards commercially available for 18:2ME isomers, and in elucidating the elution order of these isomers this study should help the future identification of cis- and trans-type of 18:2ME. We also report the identification method of cis- and trans-type of FAME using equivalent chain lengths and attempt the identification of cis- and trans-type of 18:2ME isomers from partially hydrogenated canola oil.

The dynamics of a forced coupled network of active elements

NASA Astrophysics Data System (ADS)

Parks, Helen F.; Ermentrout, Bard; Rubin, Jonathan E.

2011-03-01

This paper presents the derivation and analysis of mathematical models motivated by the experimental induction of contour phosphenes in the retina. First, a spatially discrete chain of periodically forced coupled oscillators is considered via reduction to a chain of scalar phase equations. Each isolated oscillator locks in a 1:2 manner with the forcing so that there is intrinsic bistability, with activity peaking on either the odd or even cycles of the forcing. If half the chain is started on the odd cycle and half on the even cycle (“split state”), then with sufficiently strong coupling, a wave can be produced that can travel in either direction due to symmetry. Numerical and analytic methods are employed to determine the size of coupling necessary for the split state solution to destabilize such that waves appear. Taking a continuum limit, we reduce the chain to a partial differential equation. We use a Melnikov function to compute, to leading order, the speed of the traveling wave solution to the partial differential equation as a function of the form of coupling and the forcing parameters and compare our result to the numerically computed discrete and continuum wave speeds.

Effect of partially depolymerized guar gum on acute metabolic variables in patients with non-insulin-dependent diabetes.

PubMed

Gatenby, S J; Ellis, P R; Morgan, L M; Judd, P A

1996-04-01

Fourteen patients with non-insulin-dependent diabetes (NIDDM) attended the study centre on 4 mornings separated by at least 3 days, to receive in random order 75 g carbohydrate breakfast meals of control or guar breads with jam and butter. Guar gum flours of low, medium, and high molecular weight (MW) were incorporated into wheat bread rolls to provide 7.6 g guar per meal. Venous blood samples were taken via an indwelling cannula in a forearm vein at fasting and at eight postprandial times and then analysed for blood glucose, plasma insulin, C-peptide, and gastric inhibitory polypeptide (GIP). Guar gum bread significantly reduced the postprandial rise in blood glucose, plasma insulin, and, except for bread containing low MW guar gum, plasma GIP levels compared to the control. Thus, the partial depolymerization of guar gum does not diminish its physiological activity. No reductions in postprandial plasma C-peptide levels were seen after any of the guar bread meals. This suggests that guar gum attenuates the insulin concentration in peripheral venous blood in patients with NIDDM by increasing the hepatic extraction of insulin.

Higher-order hybrid implicit/explicit FDTD time-stepping

NASA Astrophysics Data System (ADS)

Tierens, W.

2016-12-01

Both partially implicit FDTD methods, and symplectic FDTD methods of high temporal accuracy (3rd or 4th order), are well documented in the literature. In this paper we combine them: we construct a conservative FDTD method which is fourth order accurate in time and is partially implicit. We show that the stability condition for this method depends exclusively on the explicit part, which makes it suitable for use in e.g. modelling wave propagation in plasmas.

Order priors for Bayesian network discovery with an application to malware phylogeny

DOE PAGES

Oyen, Diane; Anderson, Blake; Sentz, Kari; ...

2017-09-15

Here, Bayesian networks have been used extensively to model and discover dependency relationships among sets of random variables. We learn Bayesian network structure with a combination of human knowledge about the partial ordering of variables and statistical inference of conditional dependencies from observed data. Our approach leverages complementary information from human knowledge and inference from observed data to produce networks that reflect human beliefs about the system as well as to fit the observed data. Applying prior beliefs about partial orderings of variables is an approach distinctly different from existing methods that incorporate prior beliefs about direct dependencies (or edges)more » in a Bayesian network. We provide an efficient implementation of the partial-order prior in a Bayesian structure discovery learning algorithm, as well as an edge prior, showing that both priors meet the local modularity requirement necessary for an efficient Bayesian discovery algorithm. In benchmark studies, the partial-order prior improves the accuracy of Bayesian network structure learning as well as the edge prior, even though order priors are more general. Our primary motivation is in characterizing the evolution of families of malware to aid cyber security analysts. For the problem of malware phylogeny discovery, we find that our algorithm, compared to existing malware phylogeny algorithms, more accurately discovers true dependencies that are missed by other algorithms.« less

Order priors for Bayesian network discovery with an application to malware phylogeny

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

Oyen, Diane; Anderson, Blake; Sentz, Kari

Here, Bayesian networks have been used extensively to model and discover dependency relationships among sets of random variables. We learn Bayesian network structure with a combination of human knowledge about the partial ordering of variables and statistical inference of conditional dependencies from observed data. Our approach leverages complementary information from human knowledge and inference from observed data to produce networks that reflect human beliefs about the system as well as to fit the observed data. Applying prior beliefs about partial orderings of variables is an approach distinctly different from existing methods that incorporate prior beliefs about direct dependencies (or edges)more » in a Bayesian network. We provide an efficient implementation of the partial-order prior in a Bayesian structure discovery learning algorithm, as well as an edge prior, showing that both priors meet the local modularity requirement necessary for an efficient Bayesian discovery algorithm. In benchmark studies, the partial-order prior improves the accuracy of Bayesian network structure learning as well as the edge prior, even though order priors are more general. Our primary motivation is in characterizing the evolution of families of malware to aid cyber security analysts. For the problem of malware phylogeny discovery, we find that our algorithm, compared to existing malware phylogeny algorithms, more accurately discovers true dependencies that are missed by other algorithms.« less

Bounding the Resource Availability of Partially Ordered Events with Constant Resource Impact

NASA Technical Reports Server (NTRS)

Frank, Jeremy

2004-01-01

We compare existing techniques to bound the resource availability of partially ordered events. We first show that, contrary to intuition, two existing techniques, one due to Laborie and one due to Muscettola, are not strictly comparable in terms of the size of the search trees generated under chronological search with a fixed heuristic. We describe a generalization of these techniques called the Flow Balance Constraint to tightly bound the amount of available resource for a set of partially ordered events with piecewise constant resource impact We prove that the new technique generates smaller proof trees under chronological search with a fixed heuristic, at little increase in computational expense. We then show how to construct tighter resource bounds but at increased computational cost.

Polymer Electrolyte Fuel Cells Employing Heteropolyacids as Redox Mediators for Oxygen Reduction Reactions: Pt-Free Cathode Systems.

PubMed

Matsui, Toshiaki; Morikawa, Eri; Nakada, Shintaro; Okanishi, Takeou; Muroyama, Hiroki; Hirao, Yoshifumi; Takahashi, Tsuyoshi; Eguchi, Koichi

2016-07-20

In this study, the heteropolyacids of H3+xPVxMO12-xO40 (x = 0, 2, and 3) were applied as redox mediators for the oxygen reduction reaction in polymer electrolyte fuel cells, of which the cathode is free from the usage of noble metals such as Pt/C. In this system, the electrochemical reduction of heteropolyacid over the carbon cathode and the subsequent reoxidation of the partially reduced heteropolyacid by exposure to the dissolved oxygen in the regenerator are important processes for continuous power generation. Thus, the redox properties of catholytes containing these heteropolyacids were investigated in detail. The substitution quantity of V in the heteropolyacid affected the onset reduction potential as well as the reduction current density, resulting in a difference in cell performance. The chemical composition of heteropolyacid also had a significant impact on the reoxidation property. Among the three compounds, H6PV3Mo9O40 was the most suitable redox mediator. Furthermore, the pH of the catholyte was found to be the crucial factor in determining the reoxidation rate of partially reduced heteropolyacid as well as cell performance.

Controller reduction by preserving impulse response energy

NASA Technical Reports Server (NTRS)

Craig, Roy R., Jr.; Su, Tzu-Jeng

1989-01-01

A model order reduction algorithm based on a Krylov recurrence formulation is developed to reduce order of controllers. The reduced-order controller is obtained by projecting the full-order LQG controller onto a Krylov subspace in which either the controllability or the observability grammian is equal to the identity matrix. The reduced-order controller preserves the impulse response energy of the full-order controller and has a parameter-matching property. Two numerical examples drawn from other controller reduction literature are used to illustrate the efficacy of the proposed reduction algorithm.

Investigation into the acute effects of total and partial energy restriction on postprandial metabolism among overweight/obese participants.

PubMed

Antoni, Rona; Johnston, Kelly L; Collins, Adam L; Robertson, M Denise

2016-03-28

The intermittent energy restriction (IER) approach to weight loss involves short periods of substantial (75-100 %) energy restriction (ER) interspersed with normal eating. This study aimed to characterise the early metabolic response to these varying degrees of ER, which occurs acutely and prior to weight loss. Ten (three female) healthy, overweight/obese participants (36 (SEM 5) years; 29·0 (sem 1·1) kg/m2) took part in this acute three-way cross-over study. Participants completed three 1-d dietary interventions in a randomised order with a 1-week washout period: isoenergetic intake, partial 75 % ER and total 100 % ER. Fasting and postprandial (6-h) metabolic responses to a liquid test meal were assessed the following morning via serial blood sampling and indirect calorimetry. Food intake was also recorded for two subsequent days of ad libitum intake. Relative to the isoenergetic control, postprandial glucose responses were increased following total ER (+142 %; P=0·015) and to a lesser extent after partial ER (+76 %; P=0·051). There was also a delay in the glucose time to peak after total ER only (P=0·024). Both total and partial ER interventions produced comparable reductions in postprandial TAG responses (-75 and -59 %, respectively; both P<0·05) and 3-d energy intake deficits of approximately 30 % (both P=0·015). Resting and meal-induced thermogenesis were not significantly affected by either ER intervention. In conclusion, our data demonstrate the ability of substantial ER to acutely alter postprandial glucose-lipid metabolism (with partial ER producing the more favourable overall response), as well as incomplete energy-intake compensation amongst overweight/obese participants. Further investigations are required to establish how metabolism adapts over time to the repeated perturbations experienced during IER, as well as the implications for long-term health.

Parallel Nonnegative Least Squares Solvers for Model Order Reduction

DTIC Science & Technology

2016-03-01

NNLS problems that arise when the Energy Conserving Sampling and Weighting hyper -reduction procedure is used when constructing a reduced-order model...ScaLAPACK and performance results are presented. nonnegative least squares, model order reduction, hyper -reduction, Energy Conserving Sampling and...optimal solution. ........................................ 20 Table 6 Reduced mesh sizes produced for each solver in the ECSW hyper -reduction step

Nucleon-nucleon interactions from dispersion relations: Elastic partial waves

NASA Astrophysics Data System (ADS)

Albaladejo, M.; Oller, J. A.

2011-11-01

We consider nucleon-nucleon (NN) interactions from chiral effective field theory. In this work we restrict ourselves to the elastic NN scattering. We apply the N/D method to calculate the NN partial waves taking as input the one-pion exchange discontinuity along the left-hand cut. This discontinuity is amenable to a chiral power counting as discussed by Lacour, Oller, and Meißner [Ann. Phys. (NY)APNYA60003-491610.1016/j.aop.2010.06.012 326, 241 (2011)], with one-pion exchange as its leading order contribution. The resulting linear integral equation for a partial wave with orbital angular momentum ℓ≥2 is solved in the presence of ℓ-1 constraints, so as to guarantee the right behavior of the D- and higher partial waves near threshold. The calculated NN partial waves are based on dispersion relations and are independent of regulator. This method can also be applied to higher orders in the calculation of the discontinuity along the left-hand cut and extended to triplet coupled partial waves.

Reduction and alkylation of peanut allergen isoforms Ara h 2 and Ara h 6; characterization of intermediate- and end products.

PubMed

Apostolovic, Danijela; Luykx, Dion; Warmenhoven, Hans; Verbart, Dennis; Stanic-Vucinic, Dragana; de Jong, Govardus A H; Velickovic, Tanja Cirkovic; Koppelman, Stef J

2013-12-01

Conglutins, the major peanut allergens, Ara h 2 and Ara h 6, are highly structured proteins stabilized by multiple disulfide bridges and are stable towards heat-denaturation and digestion. We sought a way to reduce their potent allergenicity in view of the development of immunotherapy for peanut allergy. Isoforms of conglutin were purified, reduced with dithiothreitol and subsequently alkylated with iodoacetamide. The effect of this modification was assessed on protein folding and IgE-binding. We found that all disulfide bridges were reduced and alkylated. As a result, the secondary structure lost α-helix and gained some β-structure content, and the tertiary structure stability was reduced. On a functional level, the modification led to a strongly decreased IgE-binding. Using conditions for limited reduction and alkylation, partially reduced and alkylated proteins were found with rearranged disulfide bridges and, in some cases, intermolecular cross-links were found. Peptide mass finger printing was applied to control progress of the modification reaction and to map novel disulfide bonds. There was no preference for the order in which disulfides were reduced, and disulfide rearrangement occurred in a non-specific way. Only minor differences in kinetics of reduction and alkylation were found between the different conglutin isoforms. We conclude that the peanut conglutins Ara h 2 and Ara h 6 can be chemically modified by reduction and alkylation, such that they substantially unfold and that their allergenic potency decreases. © 2013.

Dimension reduction of frequency-based direct Granger causality measures on short time series.

PubMed

Siggiridou, Elsa; Kimiskidis, Vasilios K; Kugiumtzis, Dimitris

2017-09-01

The mainstream in the estimation of effective brain connectivity relies on Granger causality measures in the frequency domain. If the measure is meant to capture direct causal effects accounting for the presence of other observed variables, as in multi-channel electroencephalograms (EEG), typically the fit of a vector autoregressive (VAR) model on the multivariate time series is required. For short time series of many variables, the estimation of VAR may not be stable requiring dimension reduction resulting in restricted or sparse VAR models. The restricted VAR obtained by the modified backward-in-time selection method (mBTS) is adapted to the generalized partial directed coherence (GPDC), termed restricted GPDC (RGPDC). Dimension reduction on other frequency based measures, such the direct directed transfer function (dDTF), is straightforward. First, a simulation study using linear stochastic multivariate systems is conducted and RGPDC is favorably compared to GPDC on short time series in terms of sensitivity and specificity. Then the two measures are tested for their ability to detect changes in brain connectivity during an epileptiform discharge (ED) from multi-channel scalp EEG. It is shown that RGPDC identifies better than GPDC the connectivity structure of the simulated systems, as well as changes in the brain connectivity, and is less dependent on the free parameter of VAR order. The proposed dimension reduction in frequency measures based on VAR constitutes an appropriate strategy to estimate reliably brain networks within short-time windows. Copyright © 2017 Elsevier B.V. All rights reserved.

Percutaneous Treatment of Renal Cysts with OK-432 Sclerosis

PubMed Central

Cho, Soung Yong; Cho, Kang Su; Lee, Dong Hoon; Lee, Seung Hwan

2007-01-01

Purpose The aim of this study was to demonstrate OK-432 sclerotherapy efficacy for treatment of simple renal cysts. Materials and Methods Twenty patients with 25 symptomatic or large simple cysts were treated by ultrasonography (US)-guided percutaneous aspiration and injection of OK-432 (8 men and 12 women, mean age 63.6 years, SD 9.5). Six patients presented with flank pain, 14 presented with renal mass; renal cyst location was right, left, or bilateral sided in 9, 8, and 8 kidneys, respectively. Patients were evaluated by clinical assessment, US, or CT scan 3 months following the procedure. Complete and partial success was defined as symptom resolution with either total cyst ablation or greater than 70% reduction, respectively. Failure was defined as 30% of cyst size recurrence and/or persistent symptoms. Results Average reduction was 93.0%. Complete and partial resolution occurred in 11 (44.0%) and 13 (52.0%) cysts, respectively. One case was defined as failure, with a 64.2% size reduction from 10.9cm to 3.9cm (volume reduction rate 95.4%). Renal pain improved in all patients, regardless of complete or partial resolution. Minor complications occurred in 3 patients, 2 developed leukocytosis and 1 had mild fever (< 38.5℃) following aspiration and sclerotherapy. Successful treatment was achieved with conservative measures and NSAID therapy. Conclusion Percutaneous treatment of simple renal cysts with OK-432 sclerotherapy was found to be a safe, effective and minimally invasive procedure. PMID:17461526

On partially massless theory in 3 dimensions

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

Alexandrov, Sergei; Laboratoire Charles Coulomb UMR 5221, CNRS, Place Eugène Bataillon, F-34095, Montpellier; Deffayet, Cédric

2015-03-24

We analyze the first-order formulation of the ghost-free bigravity model in three-dimensions known as zwei-dreibein gravity. For a special choice of parameters, it was argued to have an additional gauge symmetry and give rise to a partially massless theory. We provide a thorough canonical analysis and identify that whether the theory becomes partially massless depends on the form of the stability condition of the secondary constraint responsible for the absence of the ghost. Generically, it is found to be an equation for a Lagrange multiplier implying that partially massless zwei-dreibein gravity does not exist. However, for special backgrounds this conditionmore » is identically satisfied leading to the presence of additional symmetries, which however disappear at quadratic order in perturbations.« less

On partially massless theory in 3 dimensions

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

Alexandrov, Sergei; Deffayet, Cédric, E-mail: salexand@univ-montp2.fr, E-mail: deffayet@iap.fr

2015-03-01

We analyze the first-order formulation of the ghost-free bigravity model in three-dimensions known as zwei-dreibein gravity. For a special choice of parameters, it was argued to have an additional gauge symmetry and give rise to a partially massless theory. We provide a thorough canonical analysis and identify that whether the theory becomes partially massless depends on the form of the stability condition of the secondary constraint responsible for the absence of the ghost. Generically, it is found to be an equation for a Lagrange multiplier implying that partially massless zwei-dreibein gravity does not exist. However, for special backgrounds this conditionmore » is identically satisfied leading to the presence of additional symmetries, which however disappear at quadratic order in perturbations.« less

Reciprocal links among differential parenting, perceived partiality, and self-worth: a three-wave longitudinal study.

PubMed

Shebloski, Barbara; Conger, Katherine J; Widaman, Keith F

2005-12-01

This study examined reciprocal links between parental differential treatment, siblings' perception of partiality, and self-worth with 3 waves of data from 384 adolescent sibling dyads. Results suggest that birth-order status was significantly associated with self-worth and perception of maternal and paternal differential treatment. There was a consistent across-time effect of self-worth on perception of parental partiality for later born siblings, but not earlier born siblings, and a consistent effect of differential treatment on perception of partiality for earlier born but not later born siblings. The results contribute new insight into the associations between perception of differential parenting and adolescents' adjustment and the role of birth order. Copyright 2006 APA, all rights reserved).

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

Deline, C.

Computer modeling is able to predict the performance of distributed power electronics (microinverters, power optimizers) in PV systems. However, details about partial shade and other mismatch must be known in order to give the model accurate information to go on. This talk will describe recent updates in NREL’s System Advisor Model program to model partial shading losses with and without distributed power electronics, along with experimental validation results. Computer modeling is able to predict the performance of distributed power electronics (microinverters, power optimizers) in PV systems. However, details about partial shade and other mismatch must be known in order tomore » give the model accurate information to go on. This talk will describe recent updates in NREL’s System Advisor Model program to model partial shading losses.« less

Effects of harvesting on nitrogen and phosphorus availability in riparian management zone soils in Minnesota, USA

Treesearch

Douglas N. Kastendick; Eric K. Zenner; Brian J. Palik; Randall K. Kolka; Charles R. Blinn

2012-01-01

Riparian management zones (RMZs) protect streams from excess nutrients, yet few studies have looked at soil nutrients in forested RMZs or the impacts of partial harvesting on nutrient availability. We investigated the impacts of upland clearcutting in conjunction with uncut and partially harvested RMZs (40% basal area reduction) on soil nutrients in forests in...

26 CFR 1.46-9 - Requirements for taxpayers electing an extra one-half percent additional investment credit.

Code of Federal Regulations, 2010 CFR

2010-04-01

... otherwise. (3) No partial election. To reduce administrative costs, a plan may establish a ceiling on... not a partial election prohibited by § 1.46-8(c)(5). (4) Funding a TRASOP—(i) Employer contributions... pledge. A reduction may not yield a negative balance in a participant's account. (iii) Disposing of...

11. GIRDER PARTIAL ELEVATION AND SECTIONS, 80 FOOT THROUGH PLATE ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

11. GIRDER PARTIAL ELEVATION AND SECTIONS, 80 FOOT THROUGH PLATE GIRDER SPAN. (Also includes a Marking Diagram and a schedule of parts.) American Bridge Company, Ambridge Plant No. 5, sheet no. 1, dated April 7, 1928, order no. F5073. For U.S. Steel Products Company, Pacific Coast Depot, order no. SF578. For Southern Pacific Company, order no. 8873-P-28746. Scale 1/4 inch to one foot. - Napa River Railroad Bridge, Spanning Napa River, east of Soscol Avenue, Napa, Napa County, CA

77 FR 46111 - Public Land Order No. 7792; Partial Revocation, Power Site Reserve No. 109; Montana

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-02

... DEPARTMENT OF THE INTERIOR Bureau of land management [MT-LLB05000-LL14300000-FQ0000; MTM 40412] Public Land Order No. 7792; Partial Revocation, Power Site Reserve No. 109; Montana AGENCY: Bureau of...--Policy, Management and Budget. [FR Doc. 2012-18888 Filed 8-1-12; 8:45 am] BILLING CODE 4310-DN-P ...

Partial Least Squares for Discrimination in fMRI Data

PubMed Central

Andersen, Anders H.; Rayens, William S.; Liu, Yushu; Smith, Charles D.

2011-01-01

Multivariate methods for discrimination were used in the comparison of brain activation patterns between groups of cognitively normal women who are at either high or low Alzheimer's disease risk based on family history and apolipoprotein-E4 status. Linear discriminant analysis (LDA) was preceded by dimension reduction using either principal component analysis (PCA), partial least squares (PLS), or a new oriented partial least squares (OrPLS) method. The aim was to identify a spatial pattern of functionally connected brain regions that was differentially expressed by the risk groups and yielded optimal classification accuracy. Multivariate dimension reduction is required prior to LDA when the data contains more feature variables than there are observations on individual subjects. Whereas PCA has been commonly used to identify covariance patterns in neuroimaging data, this approach only identifies gross variability and is not capable of distinguishing among-groups from within-groups variability. PLS and OrPLS provide a more focused dimension reduction by incorporating information on class structure and therefore lead to more parsimonious models for discrimination. Performance was evaluated in terms of the cross-validated misclassification rates. The results support the potential of using fMRI as an imaging biomarker or diagnostic tool to discriminate individuals with disease or high risk. PMID:22227352

Concomitant Ordering and Symmetry Lowering

ERIC Educational Resources Information Center

Boo, William O. J.; Mattern, Daniell L.

2008-01-01

Examples of concomitant ordering include magnetic ordering, Jahn-Teller cooperative ordering, electronic ordering, ionic ordering, and ordering of partially-filled sites. Concomitant ordering sets in when a crystal is cooled and always lowers the degree of symmetry of the crystal. Concomitant ordering concepts can also be productively applied to…

Non-linear duality invariant partially massless models?

DOE PAGES

Cherney, D.; Deser, S.; Waldron, A.; ...

2015-12-15

We present manifestly duality invariant, non-linear, equations of motion for maximal depth, partially massless higher spins. These are based on a first order, Maxwell-like formulation of the known partially massless systems. Lastly, our models mimic Dirac–Born–Infeld theory but it is unclear whether they are Lagrangian.

Feasibility Evaluation of an On-site Generator Network by the Cooperative Game Theory

NASA Astrophysics Data System (ADS)

Komiyama, Ryoichi; Hayashi, Taketo; Fujii, Yasumasa; Yamaji, Kenji

On-site generator, such as CGS (cogeneration system), is allegedly considered to be an effective end-use energy system in order to accomplish primary energy conservation, CO2 emission mitigation and system cost reduction, which characteristics eventually improve the whole performance of an existing energy system for the future. Considering the drawback of installing an end-use CGS into the customer with small or middle scale floor space, however, it is difficult to achieve those distinctive features because the thermal-electricity ratio of CGS does not always be in agreement with that of customer energy demand. In order to overcome that matching deficiency, it is hence better to organize an on-site generator network based on mutual electricity and heating transmission. But focusing on some cogenerators underlying their behaviors on maximizing their own profits, this on-site network, which situation corresponds to a grand coalition, is not necessarily established because of each cogenerator’s motivation to form a partial coalition and acquire its own profit as much as possible. In this paper, we attempt to analyze the optimal operation of an on-site generator network and identify by applying the nucleolus of the cooperative game theory the optimal benefit allocation strategy in order for the cogenerators to construct the network. Regarding the installation site of this network, the center of Tokyo area is assumed, which locational information includes floor space and so forth through a GIS (geographic information system) database. The results from the nucleolus suggest that all districts should impartially obtain the benefit from organizing network for the purpose of jointly attaining the system total cost reduction.

Large-Scale Optimization for Bayesian Inference in Complex Systems

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

Willcox, Karen; Marzouk, Youssef

2013-11-12

The SAGUARO (Scalable Algorithms for Groundwater Uncertainty Analysis and Robust Optimization) Project focused on the development of scalable numerical algorithms for large-scale Bayesian inversion in complex systems that capitalize on advances in large-scale simulation-based optimization and inversion methods. The project was a collaborative effort among MIT, the University of Texas at Austin, Georgia Institute of Technology, and Sandia National Laboratories. The research was directed in three complementary areas: efficient approximations of the Hessian operator, reductions in complexity of forward simulations via stochastic spectral approximations and model reduction, and employing large-scale optimization concepts to accelerate sampling. The MIT--Sandia component of themore » SAGUARO Project addressed the intractability of conventional sampling methods for large-scale statistical inverse problems by devising reduced-order models that are faithful to the full-order model over a wide range of parameter values; sampling then employs the reduced model rather than the full model, resulting in very large computational savings. Results indicate little effect on the computed posterior distribution. On the other hand, in the Texas--Georgia Tech component of the project, we retain the full-order model, but exploit inverse problem structure (adjoint-based gradients and partial Hessian information of the parameter-to-observation map) to implicitly extract lower dimensional information on the posterior distribution; this greatly speeds up sampling methods, so that fewer sampling points are needed. We can think of these two approaches as ``reduce then sample'' and ``sample then reduce.'' In fact, these two approaches are complementary, and can be used in conjunction with each other. Moreover, they both exploit deterministic inverse problem structure, in the form of adjoint-based gradient and Hessian information of the underlying parameter-to-observation map, to achieve their speedups.« less

Final Report: Large-Scale Optimization for Bayesian Inference in Complex Systems

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

Ghattas, Omar

2013-10-15

The SAGUARO (Scalable Algorithms for Groundwater Uncertainty Analysis and Robust Optimiza- tion) Project focuses on the development of scalable numerical algorithms for large-scale Bayesian inversion in complex systems that capitalize on advances in large-scale simulation-based optimiza- tion and inversion methods. Our research is directed in three complementary areas: efficient approximations of the Hessian operator, reductions in complexity of forward simulations via stochastic spectral approximations and model reduction, and employing large-scale optimization concepts to accelerate sampling. Our efforts are integrated in the context of a challenging testbed problem that considers subsurface reacting flow and transport. The MIT component of the SAGUAROmore » Project addresses the intractability of conventional sampling methods for large-scale statistical inverse problems by devising reduced-order models that are faithful to the full-order model over a wide range of parameter values; sampling then employs the reduced model rather than the full model, resulting in very large computational savings. Results indicate little effect on the computed posterior distribution. On the other hand, in the Texas-Georgia Tech component of the project, we retain the full-order model, but exploit inverse problem structure (adjoint-based gradients and partial Hessian information of the parameter-to- observation map) to implicitly extract lower dimensional information on the posterior distribution; this greatly speeds up sampling methods, so that fewer sampling points are needed. We can think of these two approaches as "reduce then sample" and "sample then reduce." In fact, these two approaches are complementary, and can be used in conjunction with each other. Moreover, they both exploit deterministic inverse problem structure, in the form of adjoint-based gradient and Hessian information of the underlying parameter-to-observation map, to achieve their speedups.« less

Efficacy of lacosamide by focal seizure subtype.

PubMed

Sperling, Michael R; Rosenow, Felix; Faught, Edward; Hebert, David; Doty, Pamela; Isojärvi, Jouko

2014-10-01

The purpose of this post hoc exploratory analysis was to determine the effects of the antiepileptic drug, lacosamide, on focal (partial-onset) seizure subtypes. Patient data from the three lacosamide pivotal trials were grouped and pooled by focal seizure subtype at Baseline: simple partial seizures (SPS), complex partial seizures (CPS), and secondarily generalized partial seizures (SGPS). Both efficacy outcomes (median percent change from Baseline to Maintenance Phase in seizure frequency per 28 days and the proportion of patients experiencing at least a 50% reduction in seizures) were evaluated by lacosamide dose (200, 400, or 600 mg/day) compared to placebo for each seizure subtype. An additional analysis was performed to determine whether a shift from more severe focal seizure subtypes to less severe occurred upon treatment with lacosamide. In patients with CPS or SGPS at Baseline, lacosamide 400 mg/day (maximum recommended daily dose) and 600 mg/day reduced the frequency of CPS and SGPS compared to placebo. Likewise, a proportion of patients with CPS and SGPS at Baseline experienced at least a 50% reduction in the frequency of CPS and SGPS (≥50% responder rate) in the lacosamide 400 and 600 mg/day groups compared with placebo. For both outcomes, numerically greatest responses were observed in the lacosamide 600 mg/day group among patients with SGPS at Baseline. In patients with SPS at Baseline, no difference between placebo and lacosamide was observed for either efficacy outcome. An additional exploratory analysis suggests that in patients with SPS at Baseline, CPS and SGPS may have been shifted to less severe SPS upon treatment with lacosamide. The results of these exploratory analyses revealed reductions in CPS and SGPS frequency with adjunctive lacosamide. Reduction in CPS and SGPS may confound assessment of SPS since the CPS or SGPS may possibly change to SPS by effective treatment. Copyright © 2014 Elsevier B.V. All rights reserved.

Inferring microRNA regulation of mRNA with partially ordered samples of paired expression data and exogenous prediction algorithms.

PubMed

Godsey, Brian; Heiser, Diane; Civin, Curt

2012-01-01

MicroRNAs (miRs) are known to play an important role in mRNA regulation, often by binding to complementary sequences in "target" mRNAs. Recently, several methods have been developed by which existing sequence-based target predictions can be combined with miR and mRNA expression data to infer true miR-mRNA targeting relationships. It has been shown that the combination of these two approaches gives more reliable results than either by itself. While a few such algorithms give excellent results, none fully addresses expression data sets with a natural ordering of the samples. If the samples in an experiment can be ordered or partially ordered by their expected similarity to one another, such as for time-series or studies of development processes, stages, or types, (e.g. cell type, disease, growth, aging), there are unique opportunities to infer miR-mRNA interactions that may be specific to the underlying processes, and existing methods do not exploit this. We propose an algorithm which specifically addresses [partially] ordered expression data and takes advantage of sample similarities based on the ordering structure. This is done within a Bayesian framework which specifies posterior distributions and therefore statistical significance for each model parameter and latent variable. We apply our model to a previously published expression data set of paired miR and mRNA arrays in five partially ordered conditions, with biological replicates, related to multiple myeloma, and we show how considering potential orderings can improve the inference of miR-mRNA interactions, as measured by existing knowledge about the involved transcripts.

Orders on Intervals Over Partially Ordered Sets: Extending Allen's Algebra and Interval Graph Results

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

Zapata, Francisco; Kreinovich, Vladik; Joslyn, Cliff A.

2013-08-01

To make a decision, we need to compare the values of quantities. In many practical situations, we know the values with interval uncertainty. In such situations, we need to compare intervals. Allen’s algebra describes all possible relations between intervals on the real line, and ordering relations between such intervals are well studied. In this paper, we extend this description to intervals in an arbitrary partially ordered set (poset). In particular, we explicitly describe ordering relations between intervals that generalize relation between points. As auxiliary results, we provide a logical interpretation of the relation between intervals, and extend the results aboutmore » interval graphs to intervals over posets.« less

THE EFFECT OF SULFUR ON METHANE PARTIAL OXIDATION AND REFORMING PROCESSES FOR LEAN NOX TRAP CATALYSIS

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

Parks, II, James E; Ponnusamy, Senthil

2006-01-01

Lean NOx trap catalysis has demonstrated the ability to reduce NOx emissions from lean natural gas reciprocating engines by >90%. The technology operates in a cyclic fashion where NOx is trapped on the catalyst during lean operation and released and reduced to N2 under rich exhaust conditions; the rich cleansing operation of the cycle is referred to as "regeneration" since the catalyst is reactivated for more NOx trapping after NOx purge. Creating the rich exhaust conditions for regeneration can be accomplished by catalytic partial oxidation of methane in the exhaust system. Furthermore, catalytic reforming of partial oxidation exhaust can enablemore » increased quantities of H2 which is an excellent reductant for lean NOx trap regeneration. It is critical to maintain clean and efficient partial oxidation and reforming processes to keep the lean NOx trap functioning properly and to reduce extra fuel consumption from the regeneration process. Although most exhaust constituents do not impede partial oxidation and reforming, some exhaust constituents may negatively affect the catalysts and result in loss of catalytic efficiency. Of particular concern are common catalyst poisons sulfur, zinc, and phosphorous. These poisons form in the exhaust through combustion of fuel and oil, and although they are present at low concentrations, they can accumulate to significant levels over the life of an engine system. In the work presented here, the effects of sulfur on the partial oxidation and reforming catalytic processes were studied to determine any durability limitations on the production of reductants for lean NOx trap catalyst regeneration.« less

A proposed standard method for polarimetric calibration and calibration verification

NASA Astrophysics Data System (ADS)

Persons, Christopher M.; Jones, Michael W.; Farlow, Craig A.; Morell, L. Denise; Gulley, Michael G.; Spradley, Kevin D.

2007-09-01

Accurate calibration of polarimetric sensors is critical to reducing and analyzing phenomenology data, producing uniform polarimetric imagery for deployable sensors, and ensuring predictable performance of polarimetric algorithms. It is desirable to develop a standard calibration method, including verification reporting, in order to increase credibility with customers and foster communication and understanding within the polarimetric community. This paper seeks to facilitate discussions within the community on arriving at such standards. Both the calibration and verification methods presented here are performed easily with common polarimetric equipment, and are applicable to visible and infrared systems with either partial Stokes or full Stokes sensitivity. The calibration procedure has been used on infrared and visible polarimetric imagers over a six year period, and resulting imagery has been presented previously at conferences and workshops. The proposed calibration method involves the familiar calculation of the polarimetric data reduction matrix by measuring the polarimeter's response to a set of input Stokes vectors. With this method, however, linear combinations of Stokes vectors are used to generate highly accurate input states. This allows the direct measurement of all system effects, in contrast with fitting modeled calibration parameters to measured data. This direct measurement of the data reduction matrix allows higher order effects that are difficult to model to be discovered and corrected for in calibration. This paper begins with a detailed tutorial on the proposed calibration and verification reporting methods. Example results are then presented for a LWIR rotating half-wave retarder polarimeter.

Laparoscopic Partial Nephrectomy with Diode Laser: A Promising Technique

PubMed Central

Knezevic, Nikola; Maric, Marjan; Grkovic, Marija Topalovic; Krhen, Ivan; Kastelan, Zeljko

2014-01-01

Abstract Objective: The aim of this study was to evaluate application of diode laser in laparoscopic partial nephrectomy (LPN), and to question this technique in terms of ease of tumor excision and reduction of warm ischemia time (WIT). Background data: LPN is the standard operative method for small renal masses. The benefits of LPN are numerous, including preserving renal function and prolonging overall survival. However, reduction of WIT remains main challenge in this operation. In order to shorten WIT, many techniques have been developed, with variable results. Patients and methods: We performed a prospective collection and analysis of health records for patients who were operated on between March 2011 and August 2012. Inclusion criteria were single tumor ≤4 cm, predominant exophytic growth and intraparenchymal depth ≤1.5 cm, with a minimum distance of 5 mm from the urinary collecting system. Results: We operated on 17 patients. Median operative time was 170 min. In all but two patients, we had to perform hilar clamping. Median duration of WIT was 16 min. Pathohistological evaluation revealed clear cell renal cancer and confirmed margins negative for tumor in all cases. Median size of the tumor was 3 cm. Median postoperative hospitalization was 5 days. Average follow up was 11.5 months. There were no intraoperative complications. One postoperative complication was noted: perirenal hematoma. Conclusions: Laser LPN is feasible, and offers the benefit of shorter WIT, with effective tissue coagulation and hemostasis. With operative experience and technical advances, WIT will be reduced or even eliminated, and a solution to some technical difficulties, such as significant smoke production, will be found. PMID:24460067

Partial replacement of fossil fuel in a cement plant: risk assessment for the population living in the neighborhood.

PubMed

Rovira, Joaquim; Mari, Montse; Nadal, Martí; Schuhmacher, Marta; Domingo, José L

2010-10-15

In cement plants, the substitution of traditional fossil fuels not only allows a reduction of CO(2), but it also means to check-out residual materials, such as sewage sludge or municipal solid wastes (MSW), which should otherwise be disposed somehow/somewhere. In recent months, a cement plant placed in Alcanar (Catalonia, Spain) has been conducting tests to replace fossil fuel by refuse-derived fuel (RDF) from MSW. In July 2009, an operational test was progressively initiated by reaching a maximum of partial substitution of 20% of the required energy. In order to study the influence of the new process, environmental monitoring surveys were performed before and after the RDF implementation. Metals and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) were analyzed in soil, herbage, and air samples collected around the facility. In soils, significant decreases of PCDD/F levels, as well as in some metal concentrations were found, while no significant increases in the concentrations of these pollutants were observed. In turn, PM(10) levels remained constant, with a value of 16μgm(-3). In both surveys, the carcinogenic and non-carcinogenic risks derived from exposure to metals and PCDD/Fs for the population living in the vicinity of the facility were within the ranges considered as acceptable according to national and international standards. This means that RDF may be a successful choice in front of classical fossil fuels, being in accordance with the new EU environmental policies, which entail the reduction of CO(2) emissions and the energetic valorization of MSW. However, further long-term environmental studies are necessary to corroborate the harmlessness of RDF, in terms of human health risks. Copyright © 2010 Elsevier B.V. All rights reserved.

Polymer Coatings Degradation Properties

DTIC Science & Technology

1985-02-01

undertaken 124). The Box-Jenkins approach first evaluates the partial auto -correlation function and determines the order of the moving average memory function...78 - Tables 15 and 16 show the resalit- f- a, the partial auto correlation plots. Second order moving .-. "ra ;;th -he appropriate lags were...coated films. Kaempf, Guenter; Papenroth, Wolfgang; Kunststoffe Date: 1982 Volume: 72 Number:7 Pages: 424-429 Parameters influencing the accelerated

A novel method for identification of lithium-ion battery equivalent circuit model parameters considering electrochemical properties

NASA Astrophysics Data System (ADS)

Zhang, Xi; Lu, Jinling; Yuan, Shifei; Yang, Jun; Zhou, Xuan

2017-03-01

This paper proposes a novel parameter identification method for the lithium-ion (Li-ion) battery equivalent circuit model (ECM) considering the electrochemical properties. An improved pseudo two-dimension (P2D) model is established on basis of partial differential equations (PDEs), since the electrolyte potential is simplified from the nonlinear to linear expression while terminal voltage can be divided into the electrolyte potential, open circuit voltage (OCV), overpotential of electrodes, internal resistance drop, and so on. The model order reduction process is implemented by the simplification of the PDEs using the Laplace transform, inverse Laplace transform, Pade approximation, etc. A unified second order transfer function between cell voltage and current is obtained for the comparability with that of ECM. The final objective is to obtain the relationship between the ECM resistances/capacitances and electrochemical parameters such that in various conditions, ECM precision could be improved regarding integration of battery interior properties for further applications, e.g., SOC estimation. Finally simulation and experimental results prove the correctness and validity of the proposed methodology.

Effects of the non-extensive parameter on the propagation of ion acoustic waves in five-component cometary plasma system

NASA Astrophysics Data System (ADS)

Mahmoud, Abeer A.

2018-01-01

Some important evolution nonlinear partial differential equations are derived using the reductive perturbation method for unmagnetized collisionless system of five component plasma. This plasma system is a multi-ion contains negatively and positively charged Oxygen ions (heavy ions), positive Hydrogen ions (lighter ions), hot electrons from solar origin and colder electrons from cometary origin. The positive Hydrogen ion and the two types of electrons obey q-non-extensive distributions. The derived equations have three types of ion acoustic waves, which are soliton waves, shock waves and kink waves. The effects of the non-extensive parameters for the hot electrons, the colder electrons and the Hydrogen ions on the propagation of the envelope waves are studied. The compressive and rarefactive shapes of the three envelope waves appear in this system for the first order of the power of the nonlinearity strength with different values of non-extensive parameters. For the second order, the strength of nonlinearity will increase and the compressive type of the envelope wave only appears.

A spectral-finite difference solution of the Navier-Stokes equations in three dimensions

NASA Astrophysics Data System (ADS)

Alfonsi, Giancarlo; Passoni, Giuseppe; Pancaldo, Lea; Zampaglione, Domenico

1998-07-01

A new computational code for the numerical integration of the three-dimensional Navier-Stokes equations in their non-dimensional velocity-pressure formulation is presented. The system of non-linear partial differential equations governing the time-dependent flow of a viscous incompressible fluid in a channel is managed by means of a mixed spectral-finite difference method, in which different numerical techniques are applied: Fourier decomposition is used along the homogeneous directions, second-order Crank-Nicolson algorithms are employed for the spatial derivatives in the direction orthogonal to the solid walls and a fourth-order Runge-Kutta procedure is implemented for both the calculation of the convective term and the time advancement. The pressure problem, cast in the Helmholtz form, is solved with the use of a cyclic reduction procedure. No-slip boundary conditions are used at the walls of the channel and cyclic conditions are imposed at the other boundaries of the computing domain.Results are provided for different values of the Reynolds number at several time steps of integration and are compared with results obtained by other authors.

On the classification of scalar evolution equations with non-constant separant

NASA Astrophysics Data System (ADS)

Hümeyra Bilge, Ayşe; Mizrahi, Eti

2017-01-01

The ‘separant’ of the evolution equation u t   =  F, where F is some differentiable function of the derivatives of u up to order m, is the partial derivative \\partial F/\\partial {{u}m}, where {{u}m}={{\\partial}m}u/\\partial {{x}m} . As an integrability test, we use the formal symmetry method of Mikhailov-Shabat-Sokolov, which is based on the existence of a recursion operator as a formal series. The solvability of its coefficients in the class of local functions gives a sequence of conservation laws, called the ‘conserved densities’ {ρ(i)}, i=-1,1,2,3,\\ldots . We apply this method to the classification of scalar evolution equations of orders 3≤slant m≤slant 15 , for which {ρ(-1)}={≤ft[\\partial F/\\partial {{u}m}\\right]}-1/m} and {{ρ(1)} are non-trivial, i.e. they are not total derivatives and {ρ(-1)} is not linear in its highest order derivative. We obtain the ‘top level’ parts of these equations and their ‘top dependencies’ with respect to the ‘level grading’, that we defined in a previous paper, as a grading on the algebra of polynomials generated by the derivatives u b+i , over the ring of {{C}∞} functions of u,{{u}1},\\ldots,{{u}b} . In this setting b and i are called ‘base’ and ‘level’, respectively. We solve the conserved density conditions to show that if {ρ(-1)} depends on u,{{u}1},\\ldots,{{u}b}, then, these equations are level homogeneous polynomials in {{u}b+i},\\ldots,{{u}m} , i≥slant 1 . Furthermore, we prove that if {ρ(3)} is non-trivial, then {ρ(-1)}={≤ft(α ub2+β {{u}b}+γ \\right)}1/2} , with b≤slant 3 while if {{ρ(3)} is trivial, then {ρ(-1)}={≤ft(λ {{u}b}+μ \\right)}1/3} , where b≤slant 5 and α, β, γ, λ and μ are functions of u,\\ldots,{{u}b-1} . We show that the equations that we obtain form commuting flows and we construct their recursion operators that are respectively of orders 2 and 6 for non-trivial and trivial {{ρ(3)} respectively. Omitting lower order dependencies, we show that equations with non-trivial {ρ(3)} and b  =  3 are symmetries of the ‘essentially non-linear third order equation’ for trivial {ρ(3)} , the equations with b  =  5 are symmetries of a non-quasilinear fifth order equation obtained in previous work, while for b  =  3, 4 they are symmetries of quasilinear fifth order equations.

The feasibility of desorption on Zeolite-water pair using dry gas

NASA Astrophysics Data System (ADS)

Oktariani, E.; Nakashima, K.; Noda, A.; Xue, B.; Tahara, K.; Nakaso, K.; Fukai, J.

2018-04-01

The increase in temperature, reduction in partial pressure, reduction in concentration, purging with an inert fluid, and displacement with a more strongly adsorbing species are the basic things that occur in the practical method of desorption. In this study, dry gas at constant temperature and pressure was employed as the aid to reduce the partial pressure in the water desorption on the zeolite 13X. The objective of this study is to confirm the feasibility of desorption using dry gas experimentally and numerically. The implication of heat and mass transfers were numerically investigated to find the most influential. The results of numerical simulation agree with the experimental ones for the distribution of local temperature and average water adsorbed in the packed bed.

Cytochromes P450 Catalyze the Reduction of α,β-Unsaturated Aldehydes

PubMed Central

Amunom, Immaculate; Dieter, Laura J.; Tamasi, Viola; Cai, Jan; Conklin, Daniel J.; Srivastava, Sanjay; Martin, Martha V.; Guengerich, F. Peter; Prough, Russell A.

2011-01-01

The metabolism of α,β-unsaturated aldehydes, e.g. 4-hydroxynonenal, involves oxidation to carboxylic acids, reduction to alcohols, and glutathionylation to eventually form mercapturide conjugates. Recently we demonstrated that P450s can oxidize aldehydes to carboxylic acids, a reaction previously thought to involve aldehyde dehydrogenase. When recombinant cytochrome P450 3A4 was incubated with 4-hydroxynonenal, O2, and NADPH, several products were produced, including 1,4-dihydroxynonene (DHN), 4-hydroxy-2-nonenoic acid (HNA), and an unknown metabolite. Several P450s catalyzed the reduction reaction in the order (human) P450 2B6 ≅ P450 3A4 > P450 1A2 > P450 2J2 > (mouse) P450 2c29. Other P450s did not catalyze the reduction reaction (human P450 2E1 & rabbit P450 2B4). Metabolism by isolated rat hepatocytes showed that HNA formation was inhibited by cyanamide, while DHN formation was not affected. Troleandomycin increased HNA production 1.6-fold while inhibiting DHN formation, suggesting that P450 3A11 is a major enzyme involved in rat hepatic clearance of 4-HNE. A fluorescent assay was developed using 9-anthracenealdehyde to measure both reactions. Feeding mice diet containing t-butylated hydroxyanisole increased the level of both activities with hepatic microsomal fractions, but not proportionally. Miconazole (0.5 mM) was a potent inhibitor of these microsomal reduction reactions, while phenytoin and α-naphthoflavone (both at 0.5 mM) were partial inhibitors, suggesting the role of multiple P450 enzymes. The oxidative metabolism of these aldehydes was inhibited >90% in an Ar or CO atmosphere, while the reductive reactions were not greatly affected. These results suggest that P450s are significant catalysts of reduction of α,β-unsaturated aldehydes in liver. PMID:21766881

Detectability of Martian carbonates from orbit using thermal neutrons

NASA Technical Reports Server (NTRS)

Feldman, W. C.; Jakosky, B. M.

1991-01-01

Numerical simulations of Martian neutron leakage flux spectra are made in order to explore the detectability of magnesium and calcium carbonate deposits using neutron spectroscopic techniques from orbit. The primary signature of such deposits is found to be an enhanced thermal amplitude. Although this enhancement is weakened by: (1) partial burial beneath an aeolian regolith blanket; (2) admixture with regolith on a microscopic (centimeter) or macroscopic (tens of centimeters) scale; and (3) reduction in the areal size of the deposit, near-surface stratigraphies of carbonates hypothesized by some authors as possible on Mars are still detectable by simple neutron sensors from orbit. However, the large variations in the magnitude of the thermal neutron enhancements caused by different carbonate deposit configurations found in this study require a combined gamma ray and neutron analysis for their unique specification.

Spillover, nonlinearity, and flexible structures

NASA Technical Reports Server (NTRS)

Bass, Robert W.; Zes, Dean

1991-01-01

Many systems whose evolution in time is governed by Partial Differential Equations (PDEs) are linearized around a known equilibrium before Computer Aided Control Engineering (CACE) is considered. In this case, there are infinitely many independent vibrational modes, and it is intuitively evident on physical grounds that infinitely many actuators would be needed in order to control all modes. A more precise, general formulation of this grave difficulty (spillover problem) is due to A.V. Balakrishnan. A possible route to circumvention of this difficulty lies in leaving the PDE in its original nonlinear form, and adding the essentially finite dimensional control action prior to linearization. One possibly applicable technique is the Liapunov Schmidt rigorous reduction of singular infinite dimensional implicit function problems to finite dimensional implicit function problems. Omitting details of Banach space rigor, the formalities of this approach are given.

Initial value formulation of dynamical Chern-Simons gravity

NASA Astrophysics Data System (ADS)

Delsate, Térence; Hilditch, David; Witek, Helvi

2015-01-01

We derive an initial value formulation for dynamical Chern-Simons gravity, a modification of general relativity involving parity-violating higher derivative terms. We investigate the structure of the resulting system of partial differential equations thinking about linearization around arbitrary backgrounds. This type of consideration is necessary if we are to establish well-posedness of the Cauchy problem. Treating the field equations as an effective field theory we find that weak necessary conditions for hyperbolicity are satisfied. For the full field equations we find that there are states from which subsequent evolution is not determined. Generically the evolution system closes, but is not hyperbolic in any sense that requires a first order pseudodifferential reduction. In a cursory mode analysis we find that the equations of motion contain terms that may cause ill-posedness of the initial value problem.

EPR oximetry in three spatial dimensions using sparse spin distribution

NASA Astrophysics Data System (ADS)

Som, Subhojit; Potter, Lee C.; Ahmad, Rizwan; Vikram, Deepti S.; Kuppusamy, Periannan

2008-08-01

A method is presented to use continuous wave electron paramagnetic resonance imaging for rapid measurement of oxygen partial pressure in three spatial dimensions. A particulate paramagnetic probe is employed to create a sparse distribution of spins in a volume of interest. Information encoding location and spectral linewidth is collected by varying the spatial orientation and strength of an applied magnetic gradient field. Data processing exploits the spatial sparseness of spins to detect voxels with nonzero spin and to estimate the spectral linewidth for those voxels. The parsimonious representation of spin locations and linewidths permits an order of magnitude reduction in data acquisition time, compared to four-dimensional tomographic reconstruction using traditional spectral-spatial imaging. The proposed oximetry method is experimentally demonstrated for a lithium octa- n-butoxy naphthalocyanine (LiNc-BuO) probe using an L-band EPR spectrometer.

Modeling financial markets by self-organized criticality

NASA Astrophysics Data System (ADS)

Biondo, Alessio Emanuele; Pluchino, Alessandro; Rapisarda, Andrea

2015-10-01

We present a financial market model, characterized by self-organized criticality, that is able to generate endogenously a realistic price dynamics and to reproduce well-known stylized facts. We consider a community of heterogeneous traders, composed by chartists and fundamentalists, and focus on the role of informative pressure on market participants, showing how the spreading of information, based on a realistic imitative behavior, drives contagion and causes market fragility. In this model imitation is not intended as a change in the agent's group of origin, but is referred only to the price formation process. We introduce in the community also a variable number of random traders in order to study their possible beneficial role in stabilizing the market, as found in other studies. Finally, we also suggest some counterintuitive policy strategies able to dampen fluctuations by means of a partial reduction of information.

Educational agenda for diagnostic error reduction

PubMed Central

Trowbridge, Robert L; Dhaliwal, Gurpreet; Cosby, Karen S

2013-01-01

Diagnostic errors are a major patient safety concern. Although the majority of diagnostic errors are partially attributable to cognitive mistakes, the most effective means of improving clinician cognition in order to achieve gains in diagnostic reliability are unclear. We propose a tripartite educational agenda for improving diagnostic performance among students, residents and practising physicians. This agenda includes strengthening the metacognitive abilities of clinicians, fostering intuitive reasoning and increasing awareness of the role of systems in the diagnostic process. The evidence supporting initiatives in each of these realms is reviewed and a course of future implementation and study is proposed. The barriers to designing and implementing this agenda are substantial and include limited evidence supporting these initiatives and the challenges of changing the practice patterns of practising physicians. Implementation will need to be accompanied by rigorous evaluation. PMID:23764435

Surface settling in partially filled containers upon step reduction in gravity

NASA Technical Reports Server (NTRS)

Weislogel, Marl M.; Ross, Howard D.

1990-01-01

A large literature exists concerning the equilibrium configurations of free liquid/gas surfaces in reduced gravity environments. Such conditions generally yield surfaces of constant curvature meeting the container wall at a particular (contact) angle. The time required to reach and stabilize about this configuration is less studied for the case of sudden changes in gravity level, e.g. from normal- to low-gravity, as can occur in many drop tower experiments. The particular interest here was to determine the total reorientation time for such surfaces in cylinders (mainly), as a function primarily of contact angle and kinematic viscosity, in order to aid in the development of drop tower experiment design. A large parametric range of tests were performed and, based on an accompanying scale analysis, the complete data set was correlated. The results of other investigations are included for comparison.

Direct reconstruction of the two-dimensional pair distribution function in partially ordered systems with angular correlations.

PubMed

Zaluzhnyy, I A; Kurta, R P; Menushenkov, A P; Ostrovskii, B I; Vartanyants, I A

2016-09-01

An x-ray scattering approach to determine the two-dimensional (2D) pair distribution function (PDF) in partially ordered 2D systems is proposed. We derive relations between the structure factor and PDF that enable quantitative studies of positional and bond-orientational (BO) order in real space. We apply this approach in the x-ray study of a liquid crystal (LC) film undergoing the smectic-A-hexatic-B phase transition, to analyze the interplay between the positional and BO order during the temperature evolution of the LC film. We analyze the positional correlation length in different directions in real space.

Molybdenum Nitrogenase Catalyzes the Reduction and Coupling of CO to Form Hydrocarbons*♦

PubMed Central

Yang, Zhi-Yong; Dean, Dennis R.; Seefeldt, Lance C.

2011-01-01

The molybdenum-dependent nitrogenase catalyzes the multi-electron reduction of protons and N2 to yield H2 and 2NH3. It also catalyzes the reduction of a number of non-physiological doubly and triply bonded small molecules (e.g. C2H2, N2O). Carbon monoxide (CO) is not reduced by the wild-type molybdenum nitrogenase but instead inhibits the reduction of all substrates catalyzed by nitrogenase except protons. Here, we report that when the nitrogenase MoFe protein α-Val70 residue is substituted by alanine or glycine, the resulting variant proteins will catalyze the reduction and coupling of CO to form methane (CH4), ethane (C2H6), ethylene (C2H4), propene (C3H6), and propane (C3H8). The rates and ratios of hydrocarbon production from CO can be adjusted by changing the flux of electrons through nitrogenase, by substitution of other amino acids located near the FeMo-cofactor, or by changing the partial pressure of CO. Increasing the partial pressure of CO shifted the product ratio in favor of the longer chain alkanes and alkenes. The implications of these findings in understanding the nitrogenase mechanism and the relationship to Fischer-Tropsch production of hydrocarbons from CO are discussed. PMID:21454640

Influence of hydrostatic pressure on dynamics and spatial distribution of protein partial molar volume: time-resolved surficial Kirkwood-Buff approach.

PubMed

Yu, Isseki; Tasaki, Tomohiro; Nakada, Kyoko; Nagaoka, Masataka

2010-09-30

The influence of hydrostatic pressure on the partial molar volume (PMV) of the protein apomyoglobin (AMb) was investigated by all-atom molecular dynamics (MD) simulations. Using the time-resolved Kirkwood-Buff (KB) approach, the dynamic behavior of the PMV was identified. The simulated time average value of the PMV and its reduction by 3000 bar pressurization correlated with experimental data. In addition, with the aid of the surficial KB integral method, we obtained the spatial distributions of the components of PMV to elucidate the detailed mechanism of the PMV reduction. New R-dependent PMV profiles identified the regions that increase or decrease the PMV under the high pressure condition. The results indicate that besides the hydration in the vicinity of the protein surface, the outer space of the first hydration layer also significantly influences the total PMV change. These results provide a direct and detailed picture of pressure induced PMV reduction.

On distribution reduction and algorithm implementation in inconsistent ordered information systems.

PubMed

Zhang, Yanqin

2014-01-01

As one part of our work in ordered information systems, distribution reduction is studied in inconsistent ordered information systems (OISs). Some important properties on distribution reduction are studied and discussed. The dominance matrix is restated for reduction acquisition in dominance relations based information systems. Matrix algorithm for distribution reduction acquisition is stepped. And program is implemented by the algorithm. The approach provides an effective tool for the theoretical research and the applications for ordered information systems in practices. For more detailed and valid illustrations, cases are employed to explain and verify the algorithm and the program which shows the effectiveness of the algorithm in complicated information systems.

Partial IGF-1 deficiency is sufficient to reduce heart contractibility, angiotensin II sensibility, and alter gene expression of structural and functional cardiac proteins.

PubMed

González-Guerra, José Luis; Castilla-Cortazar, Inma; Aguirre, Gabriel A; Muñoz, Úrsula; Martín-Estal, Irene; Ávila-Gallego, Elena; Granado, Miriam; Puche, Juan E; García-Villalón, Ángel Luis

2017-01-01

Circulating levels of IGF-1 may decrease under several circumstances like ageing, metabolic syndrome, and advanced cirrhosis. This reduction is associated with insulin resistance, dyslipidemia, progression to type 2 diabetes, and increased risk for cardiovascular diseases. However, underlying mechanisms between IGF-1 deficiency and cardiovascular disease remain elusive. The specific aim of the present work was to study whether the partial IGF-1 deficiency influences heart and/or coronary circulation, comparing vasoactive factors before and after of ischemia-reperfusion (I/R). In addition, histology of the heart was performed together with cardiac gene expression for proteins involved in structure and function (extracellular matrix, contractile proteins, active peptides); carried out using microarrays, followed by RT-qPCR confirmation of the three experimental groups. IGF-1 partial deficiency is associated to a reduction in contractility and angiotensin II sensitivity, interstitial fibrosis as well as altered expression pattern of genes involved in extracellular matrix proteins, calcium dynamics, and cardiac structure and function. Although this work is descriptive, it provides a clear insight of the impact that partial IGF-1 deficiency on the heart and establishes this experimental model as suitable for studying cardiac disease mechanisms and exploring therapeutic options for patients under IGF-1 deficiency conditions.

Partial IGF-1 deficiency is sufficient to reduce heart contractibility, angiotensin II sensibility, and alter gene expression of structural and functional cardiac proteins

PubMed Central

Aguirre, Gabriel A.; Muñoz, Úrsula; Martín-Estal, Irene; Ávila-Gallego, Elena; Granado, Miriam; Puche, Juan E.; García-Villalón, Ángel Luis

2017-01-01

Circulating levels of IGF-1 may decrease under several circumstances like ageing, metabolic syndrome, and advanced cirrhosis. This reduction is associated with insulin resistance, dyslipidemia, progression to type 2 diabetes, and increased risk for cardiovascular diseases. However, underlying mechanisms between IGF-1 deficiency and cardiovascular disease remain elusive. The specific aim of the present work was to study whether the partial IGF-1 deficiency influences heart and/or coronary circulation, comparing vasoactive factors before and after of ischemia-reperfusion (I/R). In addition, histology of the heart was performed together with cardiac gene expression for proteins involved in structure and function (extracellular matrix, contractile proteins, active peptides); carried out using microarrays, followed by RT-qPCR confirmation of the three experimental groups. IGF-1 partial deficiency is associated to a reduction in contractility and angiotensin II sensitivity, interstitial fibrosis as well as altered expression pattern of genes involved in extracellular matrix proteins, calcium dynamics, and cardiac structure and function. Although this work is descriptive, it provides a clear insight of the impact that partial IGF-1 deficiency on the heart and establishes this experimental model as suitable for studying cardiac disease mechanisms and exploring therapeutic options for patients under IGF-1 deficiency conditions. PMID:28806738

A self-photoprotection mechanism helps Stipa baicalensis adapt to future climate change

PubMed Central

Song, Xiliang; Zhou, Guangsheng; Xu, Zhenzhu; Lv, Xiaomin; Wang, Yuhui

2016-01-01

We examined the photosynthetic responses of Stipa baicalensis to relative long-term exposure (42 days) to the predicted elevated temperature and water availability changes to determine the mechanisms through which the plant would acclimate to future climate change. Two thermal regimes (ambient and +4 °C) and three irrigation levels (partial, normal and excess) were used in environmental control chambers. The gas exchange parameters, light response curves and A/Ci curves were determined. The elevated temperature and partial irrigation reduced the net photosynthetic rate due to a limitation in the photosynthetic capacity instead of the intercellular CO2 concentration. Partial irrigation decreased Rubisco activation and limited RuBP regeneration. The reduction in Vcmax increased with increasing temperature. Excess irrigation offset the negative effect of drought and led to a partial recovery of the photosynthetic capacity. Although its light use efficiency was restricted, the use of light and dark respiration by Stipa baicalensis was unchanged. We concluded that nonstomatal limitation was the primary reason for photosynthesis regulation in Stipa baicalensis under relative long-term climate change conditions. Although climate change caused reductions in the light use efficiency and photosynthetic rate, a self-photoprotection mechanism in Stipa baicalensis resulted in its high ability to maintain normal live activities. PMID:27161934

The effect of partially exposed connective tissue graft on root-coverage outcomes: a systematic review and meta-analysis.

PubMed

Dodge, Austin; Garcia, Jeffrey; Luepke, Paul; Lai, Yu-Lin; Kassab, Moawia; Lin, Guo-Hao

2018-04-01

The aim of this systematic review was to compare the root-coverage outcomes of using a partially exposed connective tissue graft (CTG) technique with a fully covered CTG technique for root coverage. An electronic search up to February 28 th , 2017, was performed to identify human clinical studies with data comparing outcomes of root coverage using CTG, with and without a partially exposed graft. Five clinical studies were selected for inclusion in this review. For each study, the gain of keratinized gingiva, reduction of recession depth, number of surgical sites achieving complete root coverage, percentage of root coverage, gain of tissue thickness, and changes of probing depth and clinical attachment level were recorded. Meta-analysis for the comparison of complete root coverage between the two techniques presented no statistically significant differences. A statistically significant gain of keratinized tissue in favor of the sites with an exposed CTG and a tendency of greater reduction in recession depth were seen at the sites with a fully covered CTG. Based on the results, the use of a partially exposed CTG in root-coverage procedures could achieve greater gain in keratinized gingiva, while a fully covered CTG might be indicated for procedures aiming to reduce recession depth. © 2018 Eur J Oral Sci.

Characterization of putative class II bacteriocins identified from a non-bacteriocin-producing strain Lactobacillus casei ATCC 334.

PubMed

Kuo, Yang-Cheng; Liu, Cheng-Feng; Lin, Jhao-Fen; Li, An-Chieh; Lo, Ta-Chun; Lin, Thy-Hou

2013-01-01

Several putative class II bacteriocin-like genes were identified in Lactobacillus casei ATCC 334, all of which might encode peptides with a double-glycine leader. Six peptides encoded by these genes were heterologously expressed in Escherichia coli and then partially purified in order to test their bacteriocin activity. The results revealed that the mature LSEI_2163 peptide was a class IId bacteriocin that exhibited antimicrobial activity against some lactobacilli and several Listeria species. Similarly, mature LSEI_2386 was a putative pheromone peptide that also had significant bacteriocin activity against several Listeria species. The activities of both peptides tolerated 121°C for 30 min but not treatment with proteinase K or trypsin. The two Cys residues located at positions 4 and 24 in the mature LSEI_2163 peptide were shown by mass spectrometry to form a disulfide bridge, which was required for optimal antibacterial activity. However, replacement of one or both Cys with Ser would cause significant reduction of the antibacterial activity, the reduction being greater when only one of the Cys residues (C4S) was replaced than when both (C4S/C24S) were replaced.

[EPIZOOTOLOGICAL AND EPIDEMIOLOGICAL CHARACTERISTICS OF TULAREMIA IN GEORGIA].

PubMed

Elashvili, E; Velijanashvili, I

2017-02-01

The appropriate data as well as archival materials about the spread of Tularemia disease have been studied over of period from 1991-2014 in Georgia in order to evaluate the current situation in Kartli lowland foci as well as the main reasons of disease agent circulation and maintenance in the study area. 54 (24.6%) out of 220 suspicious cases were laboratory confirmed during the study period. Most of confirmed cases - 32 (59.26%) have been detected in Shida Kartli focus among the old population during the outbreaks in the winter period. Tularemia causative agent has been isolated from the environmental object on 87 occasions, 50 (57.5%) of them have been found in Shida Kartli and 8 (9.2%) - in Kvemo Kartli lowland. Existence of rodents and ixodes ticks in Kartli lowland greatly supports keeping up Tularemia foci in this area. The common vectors and kind of storage of disease are considered to be different species of ixodes ticks especially D. marginatus, Haem. Punctata, Haem. Sulcata. It should be noted that reduction of intensity of Tularemia agent partially should be linked to the reduction frequency of planned and intentional researches during the last period of time.

A new approach to treat discontinuities in multi-layered soils

NASA Astrophysics Data System (ADS)

Berardi, Marco; Difonzo, Fabio; Caputo, Maria; Vurro, Michele; Lopez, Luciano

2017-04-01

The water infiltration into two (or more) layered soils can give rise to preferential flow paths at the interface between different soils. The deep understanding of this phenomenon can be of great interest in modeling different environmental problems in geosciences and hydrology. Flow through layered soils arises naturally in agriculture, and layered soils are also engineered as cover liners for landfills. In particular, the treatment of the soil discontinuity is of great interest from the modeling and the numerical point of view, and is still an open problem.% (see, for example, te{Matthews_et_al,Zha_vzj_2013,DeLuca_Cepeda_ASCE_2016}). Assuming to approximate the soils with different porous media, the governing equation for this phenomenon is Richards' equation, in the following form: {eq:different_Richards_1} C_1(ψ) partial ψ/partial t = partial /partial z [ K_1(ψ) ( partial ψ/partial z - 1 ) ], \\quad if \\quad z < \\overline{z}, C_2(ψ) partial ψ/partial t = partial /partial z [ K_2(ψ) ( partial ψ/partial z - 1 ) ], \\quad if \\quad z > \\overline{z}, where \\overline{z} is the spatial threshold that identifies the change in soil structure, and C1 C_2, K_1, K_2, the hydraulic functions that describe the upper and the lower soil, respectively. The ψ-based form is used, in this work. Here we have used the Filippov's theory in order to deal with discontinuous differential systems, and we handled opportunely the numerical discretization in order to treat the abovementioned system by means of this theory, letting the discontinuity depend on the state variable. The advantage of this technique is a better insight on the solution behavior on the discontinuity surface, and the no-need to average the hydraulic conductivity field on the threshold itself, as in the existing literature.

Long-term add-on pregabalin treatment in patients with partial-onset epilepsy: pooled analysis of open-label clinical trials.

PubMed

Uthman, Basim M; Bazil, Carl W; Beydoun, Ahmad; Schulze-Bonhage, Andreas; Benabou, Reina; Whalen, Ed; Emir, Birol; Griesing, Teresa; Leon, Teresa

2010-06-01

To evaluate the safety, tolerability, and efficacy of long-term pregabalin as add-on therapy for patients with poorly controlled partial seizures. Analysis of data from six long-term clinical trials involving 2,061 patients receiving open-label pregabalin 75-600 mg/day adjunctive therapy for partial onset epilepsy refractory to multiple antiepileptic drugs. Total pregabalin exposure was 3,877 person-years. The mean duration of pregabalin treatment was 534 days (range 0.3-8 years) and 59% completed 1 year. One-third of patients discontinued for lack of efficacy. The most common dose was >or=300 mg/day; over half took >or=450 mg/day. There was a mean reduction in the 28-day seizure rate of 25-40%, and more than 40% of all patients had a >or=50% reduction in seizures from baseline during the last 3 months of treatment. Twelve percent of all patients had a 6-month period continuously free of seizures. In the last year, 6% were seizure-free for the entire year. Pregabalin was generally well-tolerated and the safety profile favorable in patients treated for up to several years, with an adverse event (AE) profile similar to short-term placebo-controlled trials. Common AEs included CNS symptoms (dizziness, somnolence, headache, and asthenia), accidental injury, and weight gain. CNS AEs tended to be mild and transient. Rates of sudden unexpected death in epilepsy (SUDEP), mortality, cancer, and status epilepticus were within the expected range for this population. Adjunctive pregabalin was effective, generally well tolerated, and safe in the long-term treatment of partial seizures, and provided clinically meaningful seizure reduction and freedom without evidence of tolerance over 2 years of follow-up.

Partial Discharge Spectral Characterization in HF, VHF and UHF Bands Using Particle Swarm Optimization.

PubMed

Robles, Guillermo; Fresno, José Manuel; Martínez-Tarifa, Juan Manuel; Ardila-Rey, Jorge Alfredo; Parrado-Hernández, Emilio

2018-03-01

The measurement of partial discharge (PD) signals in the radio frequency (RF) range has gained popularity among utilities and specialized monitoring companies in recent years. Unfortunately, in most of the occasions the data are hidden by noise and coupled interferences that hinder their interpretation and renders them useless especially in acquisition systems in the ultra high frequency (UHF) band where the signals of interest are weak. This paper is focused on a method that uses a selective spectral signal characterization to feature each signal, type of partial discharge or interferences/noise, with the power contained in the most representative frequency bands. The technique can be considered as a dimensionality reduction problem where all the energy information contained in the frequency components is condensed in a reduced number of UHF or high frequency (HF) and very high frequency (VHF) bands. In general, dimensionality reduction methods make the interpretation of results a difficult task because the inherent physical nature of the signal is lost in the process. The proposed selective spectral characterization is a preprocessing tool that facilitates further main processing. The starting point is a clustering of signals that could form the core of a PD monitoring system. Therefore, the dimensionality reduction technique should discover the best frequency bands to enhance the affinity between signals in the same cluster and the differences between signals in different clusters. This is done maximizing the minimum Mahalanobis distance between clusters using particle swarm optimization (PSO). The tool is tested with three sets of experimental signals to demonstrate its capabilities in separating noise and PDs with low signal-to-noise ratio and separating different types of partial discharges measured in the UHF and HF/VHF bands.

Contribution of partial pancreatectomy, systemic hormone delivery, and duct obliteration to glucose regulation in canine pancreas. Importance in pancreas transplantation.

PubMed

van der Burg, M P; Gooszen, H G; Guicherit, O R; Jansen, J B; Frölich, M; van Haastert, F A; Lamers, C B

1989-09-01

Our aim was to isolate and determine the contribution of partial pancreatectomy, systemic delivery of pancreatic hormones, and duct obliteration to glucose regulation after segmental pancreas transplantation in dogs. Fasting, postprandial, and intravenous glucose-stimulated glucose, insulin, glucagon, pancreatic polypeptide (PP), and cholecystokinin (CCK) and intravenous bombesin-stimulated PP levels were studied in beagles at three successive intervals in a crossover design. The first was 6 wk after partial (approximately 70%) pancreatectomy with intact regular enteric exocrine drainage from the duodenal pancreatic remnant, the next was 2 wk after venous transposition with systemic delivery of pancreatic hormones, and the third was 6 wk after in situ duct obliteration of the remnant. With partial pancreatectomy, K values were modestly diminished (30%), and a concomitant reduction of second-phase intravenous glucose-stimulated insulin release was observed. Other parameters were not significantly affected. Venous transposition doubled peripheral plasma levels of insulin under all conditions. Fasting glucose, PP, and CCK levels decreased slightly. Other parameters were not affected. Duct obliteration of the systemic draining pancreatic remnants seriously impaired glucose sensitivity, resulting in a 50% reduction of K values and fasting and sustained postprandial hyperglycemia (approximately 8 mM) and a 70-50% reduction (acute and overall responses, respectively) of intravenous glucose-stimulated insulin. Fasting hormone and postprandial insulin, glucagon, and CCK levels were not affected. The postprandial PP response was severely reduced, and bombesin-stimulated PP release was abolished by duct obliteration. We conclude that histological changes associated with duct obliteration are the major determinants of glucose regulation in segmental pancreas transplantation.(ABSTRACT TRUNCATED AT 250 WORDS)

The effect of infection order of porcine circovirus type 2 and porcine reproductive and respiratory syndrome virus on dually infected swine alveolar macrophages

PubMed Central

2012-01-01

Background Concurrent infection with porcine circovirus type 2 (PCV2) and porcine reproductive and respiratory syndrome virus (PRRSV) is known as one of the major causes for porcine respiratory disease complex (PRDC). Dual infection with PCV2 and PRRSV is consistently to have more severe clinical presentations and pulmonary lesions than infection with PCV2 alone or PRRSV alone. However, it is not known if dual infections with PCV2 and PRRSV in different infection order may lead to different clinical symptoms in the host. To mimic the possible field conditions, swine alveolar macrophages (AMs) were inoculated with PCV2 and PRRSV in vitro simultaneously or with one virus 18 h earlier than the other. The cell viability, cytopathic effects, antigen-containing rates, phagocytotic and microbial killing capabilities, cytokine profiles (IL-8, TNF-α, and IFN-α) and FasL transcripts were determined, analyzed, and compared to prove the hypothesis. Results A marked reduction in PRRSV antigen-containing rate, cytopathic effect, and TNF-α expression level was revealed in AMs inoculated with PCV2 and PRRSV simultaneously and in AMs inoculated with PCV2 first then PRRSV 18 h later, but not in AMs inoculated with PRRSV first then PCV2 18 h later. Transient decrease in phagocytosis but constant reduction in microbicidal capability in AMs in the group inoculated with PCV2 alone and constant decrease in phagocytosis and microbicidal capability in AMs in all PRRSV-inoculated groups were noted. The levels of IL-8, TNF-α, IFN-α, and FasL transcripts in AMs in all groups with dual inoculation of PCV2 and PRRSV were significantly increased regardless of the infection orders as compared with infection by PCV2 alone or PRRSV alone. Conclusions Swine AMs infected with PCV2 first then PRRSV later or infected with PCV2 and PRRSV simultaneously displayed marked reduction in PRRSV antigen-containing rate, cytopathic effect, and TNF-α expression level. The different inoculation orders of PCV2 and PRRSV in AMs leading to different results in viral antigen positivity, cytopathology, and cytokine profile may explain, at least partially, the underlying mechanism of the enhanced pulmonary lesions in PRDC exerted by dual infection with PCV2 and PRRSV and the variable clinical manifestations of PRDC-affected pigs in the field. PMID:23009687

Dynamic Decision Making under Uncertainty and Partial Information

DTIC Science & Technology

2017-01-30

order to address these problems, we investigated efficient computational methodologies for dynamic decision making under uncertainty and partial...information. In the course of this research, we developed and studied efficient simulation-based methodologies for dynamic decision making under...uncertainty and partial information; (ii) studied the application of these decision making models and methodologies to practical problems, such as those

Thumbs down: a molecular-morphogenetic approach to avian digit homology.

PubMed

Capek, Daniel; Metscher, Brian D; Müller, Gerd B

2014-01-01

Avian forelimb digit homology remains one of the standard themes in comparative biology and EvoDevo research. In order to resolve the apparent contradictions between embryological and paleontological evidence a variety of hypotheses have been presented in recent years. The proposals range from excluding birds from the dinosaur clade, to assignments of homology by different criteria, or even assuming a hexadactyl tetrapod limb ground state. At present two approaches prevail: the frame shift hypothesis and the pyramid reduction hypothesis. While the former postulates a homeotic shift of digit identities, the latter argues for a gradual bilateral reduction of phalanges and digits. Here we present a new model that integrates elements from both hypotheses with the existing experimental and fossil evidence. We start from the main feature common to both earlier concepts, the initiating ontogenetic event: reduction and loss of the anterior-most digit. It is proposed that a concerted mechanism of molecular regulation and developmental mechanics is capable of shifting the boundaries of hoxD expression in embryonic forelimb buds as well as changing the digit phenotypes. Based on a distinction between positional (topological) and compositional (phenotypic) homology criteria, we argue that the identity of the avian digits is II, III, IV, despite a partially altered phenotype. Finally, we introduce an alternative digit reduction scheme that reconciles the current fossil evidence with the presented molecular-morphogenetic model. Our approach identifies specific experiments that allow to test whether gene expression can be shifted and digit phenotypes can be altered by induced digit loss or digit gain. © 2013 Wiley Periodicals, Inc.

48 CFR 8.405-4 - Price reductions.

Code of Federal Regulations, 2013 CFR

2013-10-01

... activities may request a price reduction at any time before placing an order, establishing a BPA, or in conjunction with the annual BPA review. However, the ordering activity shall seek a price reduction when the order or BPA exceeds the simplified acquisition threshold. Schedule contractors are not required to pass...

48 CFR 8.405-4 - Price reductions.

Code of Federal Regulations, 2014 CFR

2014-10-01

... activities may request a price reduction at any time before placing an order, establishing a BPA, or in conjunction with the annual BPA review. However, the ordering activity shall seek a price reduction when the order or BPA exceeds the simplified acquisition threshold. Schedule contractors are not required to pass...

48 CFR 8.405-4 - Price reductions.

Code of Federal Regulations, 2012 CFR

2012-10-01

... activities may request a price reduction at any time before placing an order, establishing a BPA, or in conjunction with the annual BPA review. However, the ordering activity shall seek a price reduction when the order or BPA exceeds the simplified acquisition threshold. Schedule contractors are not required to pass...

48 CFR 8.405-4 - Price reductions.

Code of Federal Regulations, 2011 CFR

2011-10-01

... activities may request a price reduction at any time before placing an order, establishing a BPA, or in conjunction with the annual BPA review. However, the ordering activity shall seek a price reduction when the order or BPA exceeds the simplified acquisition threshold. Schedule contractors are not required to pass...

ADVANTG Shielding Analysis for Closure Operations in an Open-Mode Repository

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

Bevill, Aaron M; Radulescu, Georgeta; Scaglione, John M

2013-01-01

en-mode repository concepts could require worker entry into access drifts after placement of fuel casks in order to perform activities related to backfill, plug emplacement, routine maintenance, or performance confirmation. An ideal emplacement-drift shielding configuration would minimize dose to workers while maximizing airflow through the emplacement drifts. This paper presents a preliminary investigation of the feasibility and effectiveness of radiation shielding concepts that could be employed to facilitate worker operations in an open-mode repository. The repository model for this study includes pressurized-water reactor fuel assemblies (60 GWd/MTU burnup, 40 year post-irradiation cooldown) in packages of 32 assemblies. The closest fuelmore » packages are 5 meters from dosimetry voxels in the access drift. The unshielded dose to workers in the access drift is 73.7 rem/hour. Prior work suggests that open-mode repository concepts similar to this one would require 15 m3/s of ventilation airflow. Shielding concepts considered here include partial concrete plugs, labyrinthine shields, and stainless steel photon attenuator grids. Maximum dose to workers in the access drift was estimated for each shielding concept using MCNP5 with variance reduction parameters generated by ADVANTG. Because airflow through the shielding is important for open-mode repositories, a semi-empirical estimate of the head loss due to each shielding configuration was also calculated. Airflow and shielding performance vary widely among the proposed shielding configurations. Although the partial plug configuration had the best airflow performance, it allowed dose rates 1500 greater than the specified target. Labyrinthine shielding concepts yield doses on the order of 1 mrem/hour with configurations that impose 3 to 11 J/kg head loss. Adding 1 cm lead lining to the airflow channels of labyrinthine designs further reduces the worker dose by 65% to 95%. Photon-attenuator concepts may reduce worker dose to as low as 29 mrem/hour with head loss on the order of 1.9 J/kg.« less

Characteristic of nitrous oxide production in partial denitrification process with high nitrite accumulation.

PubMed

Du, Rui; Peng, Yongzhen; Cao, Shenbin; Wang, Shuying; Niu, Meng

2016-03-01

Nitrous oxide (N2O) production during the partial denitrification process with nitrate (NO3(-)-N) to nitrite (NO2(-)-N) transformation ratio of 80% was investigated in this study. Results showed that N2O was seldom observed before complete depletion of NO3(-)-N, but it was closely related to the reduction of NO2(-)-N rather than NO3(-)-N. High COD/NO3(-)-N was in favor of N2O production in partial denitrification with high NO2(-)-N accumulation. It was seriously enhanced at constant acidic pH due to the free nitrous acid (FNA) inhibition. However, the N2O production was much lower at initial pH of 5.5 and 6.5 due to the pH increase during denitrification process. Significantly, the pH turning point could be chosen as a controlled parameter to denote the end of NO3(-)-N reduction, which could not only achieve high NO2(-)-N accumulation but also decrease the N2O production significantly for practical application. Copyright © 2015 Elsevier Ltd. All rights reserved.

Sliding mode observers for automotive alternator

NASA Astrophysics Data System (ADS)

Chen, De-Shiou

Estimator development for synchronous rectification of the automotive alternator is a desirable approach for estimating alternator's back electromotive forces (EMFs) without a direct mechanical sensor of the rotor position. Recent theoretical studies show that estimation of the back EMF may be observed based on system's phase current model by sensing electrical variables (AC phase currents and DC bus voltage) of the synchronous rectifier. Observer design of the back EMF estimation has been developed for constant engine speed. In this work, we are interested in nonlinear observer design of the back EMF estimation for the real case of variable engine speed. Initial back EMF estimate can be obtained from a first-order sliding mode observer (SMO) based on the phase current model. A fourth-order nonlinear asymptotic observer (NAO), complemented by the dynamics of the back EMF with time-varying frequency and amplitude, is then incorporated into the observer design for chattering reduction. Since the cost of required phase current sensors may be prohibitive, the most applicable approach in real implementation by measuring DC current of the synchronous rectifier is carried out in the dissertation. It is shown that the DC link current consists of sequential "windows" with partial information of the phase currents, hence, the cascaded NAO is responsible not only for the purpose of chattering reduction but also for necessarily accomplishing the process of estimation. Stability analyses of the proposed estimators are considered for most linear and time-varying cases. The stability of the NAO without speed information is substantiated by both numerical and experimental results. Prospective estimation algorithms for the case of battery current measurements are investigated. Theoretical study indicates that the convergence of the proposed LAO may be provided by high gain inputs. Since the order of the LAO/NAO for the battery current case is one order higher than that of the link current measurements, it is hard to find moderate values of the input gains for the real-time sampled-data systems. Technical difficulties in implementation of such high order discrete-time nonlinear estimators have been discussed. Directions of further investigations have been provided.

Evaluation of percutaneous ethanol injections in benign thyroid nodules.

PubMed

Perez, Camila Luhm Silva; Fighera, Tayane Muniz; Miasaki, Fabiola; Mesa Junior, Cleo Otaviano; Paz Filho, Gilberto Jorge da; Graf, Hans; Carvalho, Gisah Amaral de

2014-12-01

The objective of this study was to evaluate the efficacy and safety of percutaneous ethanol injection (PEI) in the treatment of benign thyroid nodules. We evaluated 120 patients with benign thyroid nodules. Patients underwent evaluation of serum TSH and free T4, cervical ultrasound, and thyroid scintigraphy (in those with suppressed TSH levels). The application of sterile ethanol 99% was guided by ultrasound, with the injected volume amounting to one-third of the nodule volume. Response was considered complete (reduction of 90%); partial (reduction between 50 and 90%); or none (reduction of < 50%). Autonomous nodules were evaluated for normalization of TSH levels. Among the nodules studied, 30.8% were solid, 56.7% were mixed, 12.5% were cystic, and 21.6% were hyperfunctioning. The initial volume of the treated nodules ranged from 0.9 to 74.8 mL (mean 13.1 ± 12.4 mL). We performed 1-8 sessions of PEI, applying an average of 6.2 mL of ethanol for patient. After 2 years of follow-up, 17% of patients achieved a complete response (94% reduction); 53%, a partial response (70% reduction); and 30%, no response. A reduction in the volume of autonomous nodules was noted in 70% of cases, and 54% had a normalized value of TSH. The main side effect is local pain, lasting less than 24 hours in most cases. This study showed that PEI is a safe and effective procedure for treatment of benign, solid or mixed thyroid nodules. Most cases resulted in significant reduction in nodule volume, with normalization of thyroid function.

Selective disulfide reduction for labeling and enhancement of Fab antibody fragments.

PubMed

Kirley, Terence L; Greis, Kenneth D; Norman, Andrew B

2016-11-25

Many methods have been developed for chemical labeling and enhancement of the properties of antibodies and their common fragments, including the Fab and F(ab') 2 fragments. Somewhat selective reduction of some antibody disulfide bonds has been previously achieved, yielding antibodies and antibody fragments that can be labeled at defined sites, enhancing their utility and properties. Selective reduction of the two hinge disulfide bonds present in F(ab') 2 fragments using mild reduction has been useful. However, such reduction is often not quantitative and results in the reduction of multiple disulfide bonds, and therefore subsequent multiple labeling or conjugation sites are neither homogenous nor stoichiometric. Here, a simple and efficient selective reduction of the single disulfide bond linking the partial heavy chain and the intact light chain which compose the Fab fragment is accomplished utilizing tris(2-carboxyethyl)phosphine (TCEP) immobilized on agarose beads. The resultant reduced cysteine residues were labeled with several cysteine-selective fluorescent reagents, as well as by cysteine-directed PEGylation. These two cysteine residues can also be re-ligated by means of a bifunctional cysteine cross-linking agent, dibromobimane, thereby both restoring a covalent linkage between the heavy and light chains at this site, far removed from the antigen binding site, and also introducing a fluorescent probe. There are many other research and clinical uses for these selectively partially reduced Fab fragments, including biotinylation, toxin and drug conjugation, and incorporation of radioisotopes, and this technique enables simple generation of very useful Fab fragment derivatives with many potential applications. Copyright © 2016 Elsevier Inc. All rights reserved.

A Modified Formula of the First-order Approximation for Assessing the Contribution of Climate Change to Runoff Based on the Budyko Hypothesis

NASA Astrophysics Data System (ADS)

Liu, W.; Ning, T.; Han, X.

2015-12-01

The climate elasticity based on the Budyko curves has been widely used to evaluate the hydrological responses to climate change. The Mezentsev-Choudhury-Yang formula is one of the representative analytical equations for Budyko curves. Previous researches mostly used the variation of runoff (R) caused by the changes of annual precipitation (P) and potential evapotranspiration (ET0) as the hydrological response to climate change and evaluated it by a first-order approximation in a form of total differential, the major components of which include the partial derivatives of R to P and ET0, as well as climate elasticity on this basis. Based on analytic derivation and the characteristics of Budyko curves, this study proposed a modified formula of the first-order approximation to reduce the errors from the approximation. In the calculation of partial derivatives and climate elasticity, the values of P and ET0 were taken to the sum of their base values and half increments, respectively. The calculation was applied in 33 catchments of the Hai River basin in China and the results showed that the mean absolute value of relative error of approximated runoff change decreased from 8.4% to 0.4% and the maximum value, from 23.4% to 1.3%. Given the variation values of P, ET0 and the controlling parameter (n), the modified formula can exactly quantify the contributions of climate fluctuation and underlying surface change to runoff. Taking the Murray-Darling basin in Australia as an example of the contribution calculated by the modified formula, the reductions of mean annual runoff caused by changes of P, ET0 and n from 1895-1996 to 1997-2006 were 2.6, 0.6 and 2.9 mm, respectively, and the sum of them was 6.1 mm, which was completely consistent with the observed runoff. The modified formula of the first-order approximation proposed in this study can be not only used to assess the contributions of climate change to the runoff, but also widely used to analyze the effects of similar issues based on a certain functional relationship in hydrological and climate changes.

Model-order reduction of lumped parameter systems via fractional calculus

NASA Astrophysics Data System (ADS)

Hollkamp, John P.; Sen, Mihir; Semperlotti, Fabio

2018-04-01

This study investigates the use of fractional order differential models to simulate the dynamic response of non-homogeneous discrete systems and to achieve efficient and accurate model order reduction. The traditional integer order approach to the simulation of non-homogeneous systems dictates the use of numerical solutions and often imposes stringent compromises between accuracy and computational performance. Fractional calculus provides an alternative approach where complex dynamical systems can be modeled with compact fractional equations that not only can still guarantee analytical solutions, but can also enable high levels of order reduction without compromising on accuracy. Different approaches are explored in order to transform the integer order model into a reduced order fractional model able to match the dynamic response of the initial system. Analytical and numerical results show that, under certain conditions, an exact match is possible and the resulting fractional differential models have both a complex and frequency-dependent order of the differential operator. The implications of this type of approach for both model order reduction and model synthesis are discussed.

Prediction model of sinoatrial node field potential using high order partial least squares.

PubMed

Feng, Yu; Cao, Hui; Zhang, Yanbin

2015-01-01

High order partial least squares (HOPLS) is a novel data processing method. It is highly suitable for building prediction model which has tensor input and output. The objective of this study is to build a prediction model of the relationship between sinoatrial node field potential and high glucose using HOPLS. The three sub-signals of the sinoatrial node field potential made up the model's input. The concentration and the actuation duration of high glucose made up the model's output. The results showed that on the premise of predicting two dimensional variables, HOPLS had the same predictive ability and a lower dispersion degree compared with partial least squares (PLS).

Reductions in biomarkers of exposure, impacts on smoking urge and assessment of product use and tolerability in adult smokers following partial or complete substitution of cigarettes with electronic cigarettes.

PubMed

D'Ruiz, Carl D; Graff, Donald W; Robinson, Edward

2016-07-11

Electronic cigarettes (e-cigarettes) are popular alternatives to conventional cigarettes among adult smokers wishing to reduce their exposure to harmful smoke constituents. However, little information exists on the relative internal exposures resulting from the exclusive or dual use of e-cigarettes. Measurements of product use; adverse events; changes in smoking urge; and blood, urine and exhaled breath biomarkers of exposure (BoE) representing toxicants believed to contribute to smoking related diseases were made at baseline and after five days of product use in 105 clinically-confined smokers randomized into groups that partially or completely substituted their usual brand combustible cigarette with commercial e-cigarettes, or discontinued all nicotine and tobacco products. Subjects switching to e-cigarettes had significantly lower levels (29 %-95 %) of urinary BoEs after 5 days. Nicotine equivalents declined by 25 %-40 %. Dual users who substituted half of their self-reported daily cigarette consumption with e-cigarettes experienced 7 %-38 % reductions, but had increases (1 %-20 %) in nicotine equivalents. Blood nicotine biomarker levels were lower in the cessation (75 %-96 %) and e-cigarette use groups (11 %-83 %); dual users had no significant reductions. All groups experienced significant decreases in exhaled CO (27 %-89 %). Exhaled NO increases (46 %-63 %) were observed in the cessation and e-cigarette use groups; dual users had minimal changes. By Day 5, all groups had greater reductions in smoking urge compared to cessation. However, reductions were larger in the dual use group. No serious adverse events were observed. Exposures to harmful smoke toxicants were observed to be lower in smokers who completely or partially replaced their cigarettes with e-cigarettes over five days.

Dissimilatory arsenate and sulfate reduction in sediments of two hypersaline, arsenic-rich soda lakes: Mono and Searles Lakes, California

USGS Publications Warehouse

Kulp, T.R.; Hoeft, S.E.; Miller, L.G.; Saltikov, C.; Murphy, J.N.; Han, S.; Lanoil, B.; Oremland, R.S.

2006-01-01

A radioisotope method was devised to study bacterial respiratory reduction of arsenate in sediments. The following two arsenic-rich soda lakes in California were chosen for comparison on the basis of their different salinities: Mono Lake (???90 g/liter) and Searles Lake (???340 g/liter). Profiles of arsenate reduction and sulfate reduction were constructed for both lakes. Reduction of [73As] arsenate occurred at all depth intervals in the cores from Mono Lake (rate constant [k] = 0.103 to 0.04 h-1) and Searles Lake (k = 0.012 to 0.002 h-1), and the highest activities occurred in the top sections of each core. In contrast, [35S] sulfate reduction was measurable in Mono Lake (k = 7.6 ?? 104 to 3.2 ?? 10-6 h-1) but not in Searles Lake. Sediment DNA was extracted, PCR amplified, and separated by denaturing gradient gel electrophoresis (DGGE) to obtain phylogenetic markers (i.e., 16S rRNA genes) and a partial functional gene for dissimilatory arsenate reduction (arrA). The amplified arrA gene product showed a similar trend in both lakes; the signal was strongest in surface sediments and decreased to undetectable levels deeper in the sediments. More arrA gene signal was observed in Mono Lake and was detectable at a greater depth, despite the higher arsenate reduction activity observed in Searles Lake. A partial sequence (about 900 bp) was obtained for a clone (SLAS-3) that matched the dominant DGGE band found in deeper parts of the Searles Lake sample (below 3 cm), and this clone was found to be closely related to SLAS-1, a novel extremophilic arsenate respirer previously cultivated from Searles Lake. Copyright ?? 2006, American Society for Microbiology. All Rights Reserved.

Molecular dynamics simulation of cytochrome c3: studying the reduction processes using free energy calculations.

PubMed Central

Soares, C M; Martel, P J; Mendes, J; Carrondo, M A

1998-01-01

The tetraheme cytochrome c3 from Desulfovibrio vulgaris Hildenborough is studied using molecular dynamics simulation studies in explicit solvent. The high heme content of the protein, which has its core almost entirely made up of c-type heme, presents specific problems in the simulation. Instability in the structure is observed in long simulations above 1 ns, something that does not occur in a monoheme cytochrome, suggesting problems in heme parametrization. Given these stability problems, a partially restrained model, which avoids destruction of the structure, was created with the objective of performing free energy calculations of heme reduction, studies that require long simulations. With this model, the free energy of reduction of each individual heme was calculated. A correction in the long-range electrostatic interactions of charge groups belonging to the redox centers had to be made in order to make the system physically meaningful. Correlation is obtained between the calculated free energies and the experimental data for three of four hemes. However, the relative scale of the calculated energies is different from the scale of the experimental free energies. Reasons for this are discussed. In addition to the free energy calculations, this model allows the study of conformational changes upon reduction. Even if the precise details of the structural changes that take place in this system upon individual heme reduction are probably out of the reach of this study, it appears that these structural changes are small, similarly to what is observed for other redox proteins. This does not mean that their effect is minor, and one example is the conformational change observed in propionate D from heme I when heme II becomes reduced. A motion of this kind could be the basis of the experimentally observed cooperativity effects between heme reduction, namely positive cooperativity. PMID:9545034

The effects of endothelin-1 on the cardiorespiratory physiology of the freshwater trout (Oncorhynchus mykiss) and the marine dogfish (Squalus acanthias).

PubMed

Perry, S F; Montpetit, C J; McKendry, J; Desforges, P R; Gilmour, K M; Wood, C M; Olson, K R

2001-11-01

The aim of the present study was to evaluate the effects of endothelin-l-elicited cardiovascular events on respiratory gas transfer in the freshwater rainbow trout (Oncorhynchus mykiss) and the marine dogfish (Squalus acanthias). In both species, endothelin-1 (666 pmol kg(-1)) caused a rapid (within 4 min) reduction (ca. 30-50 mmHg) in arterial blood partial pressure of O2. The effects of endothelin-1 on arterial blood partial pressure of CO2 were not synchronised with the changes in O2 partial pressure and the responses were markedly different in trout and dogfish. In trout, arterial CO2 partial pressure was increased transiently by approximately 1.0 mmHg but the onset of the response was delayed and occurred 12 min after endothelin-1 injection. In contrast, CO2 partial pressure remained more-or-less constant in dogfish after injection of endothelin-1 and was increased only slightly (approximately 0.1 mmHg) after 60 min. Pre-treatment of trout with bovine carbonic anhydrase (5 mg ml(-1)) eliminated the increase in CO2 partial pressure that was normally observed after endothelin-1 injection. In both species, endothelin-1 injection caused a decrease in arterial blood pH that mirrored the changes in CO2 partial pressure. Endothelin-1 injection was associated with transient (trout) or persistent (dogfish) hyperventilation as indicated by pronounced increases in breathing frequency and amplitude. In trout, arterial blood pressure remained constant or was decreased slightly and was accompanied by a transient increase in systemic resistance, and a temporary reduction in cardiac output. The decrease in cardiac output was caused solely by a reduction in cardiac frequency; cardiac stroke volume was unaffected. In dogfish, arterial blood pressure was lowered by approximately 10 mmHg at 6-10 min after endothelin-1 injection but then was rapidly restored to pre-injection levels. The decrease in arterial blood pressure reflected an increase in branchial vascular resistance (as determined using in situ perfused gill preparations) that was accompanied by simultaneous decreases in systemic resistance and cardiac output. Cardiac frequency and stroke volume were reduced by endothelin-1 injection and thus both variables contributed to the changes in cardiac output. We conclude that the net consequences of endothelin-1 on arterial blood gases result from the opposing effects of reduced gill functional surface area (caused by vasoconstriction) and an increase in blood residence time within the gill (caused by decreased cardiac output.

21 CFR 314.55 - Pediatric use information.

Code of Federal Regulations, 2010 CFR

2010-04-01

... group have failed. (4) FDA action on waiver. FDA shall grant a full or partial waiver, as appropriate... of disease, elimination or substantial reduction of a treatment-limiting drug reaction, documented...

The effect of ilmenite viscosity on the dynamics and evolution of an overturned lunar cumulate mantle

NASA Astrophysics Data System (ADS)

Zhang, Nan; Dygert, Nick; Liang, Yan; Parmentier, E. M.

2017-07-01

Lunar cumulate mantle overturn and the subsequent upwelling of overturned mantle cumulates provide a potential framework for understanding the first-order thermochemical evolution of the Moon. Upwelling of ilmenite-bearing cumulates (IBCs) after the overturn has a dominant influence on the dynamics and long-term thermal evolution of the lunar mantle. An important parameter determining the stability and convective behavior of the IBC is its viscosity, which was recently constrained through rock deformation experiments. To examine the effect of IBC viscosity on the upwelling of overturned lunar cumulate mantle, here we conduct three-dimensional mantle convection models with an evolving core superposed by an IBC-rich layer, which resulted from mantle overturn after magma ocean solidification. Our modeling shows that a reduction of mantle viscosity by 1 order of magnitude, due to the presence of ilmenite, can dramatically change convective planform and long-term lunar mantle evolution. Our model results suggest a relatively stable partially molten IBC layer that has surrounded the lunar core to the present day.