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Sample records for absolute latency plasma

  1. Absolute parametric instability in a nonuniform plane plasma waveguide

    Indian Academy of Sciences (India)

    Khaled Hamed El-Shorbagy; Atef Ahmed El-Bendary; Shatha Jameel Monaquel

    2013-04-01

    The paper reports an analysis of the effect of spatial plasma nonuniformity on absolute parametric instability (API) of electrostatic waves in magnetized plane waveguides subjected to an intense high-frequency (HF) electric field using the separation method. In this case the effect of strong static magnetic field is considered. The problem of strong magnetic field is solved in 1D nonuniform plane plasma waveguide. The equation describing the spatial part of the electric potential is obtained. Also, the growth rates and conditions of the parametric instability for periodic and aperiodic cases are obtained. It is found that the spatial nonuniformity of the plasma exerts a stabilizing effect on the API. It is shown that the growth rates of periodic and aperiodic API in nonuniform plasma are less compared to that of uniform plasma.

  2. Reactivation from latency displays HIV particle budding at plasma membrane, accompanying CD44 upregulation and recruitment

    Directory of Open Access Journals (Sweden)

    Sano Kouichi

    2009-07-01

    Full Text Available Abstract Background It has been accepted that HIV buds from the cell surface in T lymphocytes, whereas in macrophages it buds into intracellular endosomes. Recent studies, on the other hand, suggest that HIV preferentially buds from the cell surface even in monocytic cells. However, most studies are based on observations in acutely infected cells and little is known about HIV budding concomitant with reactivation from latency. Such studies would provide a better understanding of a reservoir for HIV. Results We observed HIV budding in latently infected T lymphocytic and monocytic cell lines following TNF-α stimulation and examined the upregulation of host factors that may be involved in particle production. Electron microscopy analysis revealed that reactivation of latently infected J1.1 cells (latently infected Jurkat cells with HIV-1 and U1 cells (latently infected U937 cells with HIV-1 displayed HIV particle budding predominantly at the plasma membrane, a morphology that is similar to particle budding in acutely infected Jurkat and U937 cells. When mRNA expression levels were quantified by qRT-PCR, we found that particle production from reactivated J1.1 and U1 cells was accompanied by CD44 upregulation. This upregulation was similarly observed when Jurkat and U937 cells were acutely infected with HIV-1 but not when just stimulated with TNF-α, suggesting that CD44 upregulation was linked with HIV production but not with cell stimulation. The molecules in endocytic pathways such as CD63 and HRS were also upregulated when U1 cells were reactivated and U937 cells were acutely infected with HIV-1. Confocal microscopy revealed that these upregulated host molecules were recruited to and accumulated at the sites where mature particles were formed at the plasma membrane. Conclusion Our study indicates that HIV particles are budded at the plasma membrane upon reactivation from latency, a morphology that is similar to particle budding in acute

  3. GPUbased, Microsecond Latency, HectoChannel MIMO Feedback Control of Magnetically Confined Plasmas

    Science.gov (United States)

    Rath, Nikolaus

    Feedback control has become a crucial tool in the research on magnetic confinement of plasmas for achieving controlled nuclear fusion. This thesis presents a novel plasma feedback control system that, for the first time, employs a Graphics Processing Unit (GPU) for microsecond-latency, real-time control computations. This novel application area for GPU computing is opened up by a new system architecture that is optimized for low-latency computations on less than kilobyte sized data samples as they occur in typical plasma control algorithms. In contrast to traditional GPU computing approaches that target complex, high-throughput computations with massive amounts of data, the architecture presented in this thesis uses the GPU as the primary processing unit rather than as an auxiliary of the CPU, and data is transferred from A-D/D-A converters directly into GPU memory using peer-to-peer PCI Express transfers. The described design has been implemented in a new, GPU-based control system for the High-Beta Tokamak - Extended Pulse (HBT-EP) device. The system is built from commodity hardware and uses an NVIDIA GeForce GPU and D-TACQ A-D/D-A converters providing a total of 96 input and 64 output channels. The system is able to run with sampling periods down to 4 μs and latencies down to 8 μs. The GPU provides a total processing power of 1.5 x 1012 floating point operations per second. To illustrate the performance and versatility of both the general architecture and concrete implementation, a new control algorithm has been developed. The algorithm is designed for the control of multiple rotating magnetic perturbations in situations where the plasma equilibrium is not known exactly and features an adaptive system model: instead of requiring the rotation frequencies and growth rates embedded in the system model to be set a priori, the adaptive algorithm derives these parameters from the evolution of the perturbation amplitudes themselves. This results in non-linear control

  4. Absolute calibration of space-resolving soft X-ray spectrograph for plasma diagnostics

    Science.gov (United States)

    Yoshikawa, M.; Okamoto, Y.; Kawamori, E.; Watanabe, Y.; Watabe, C.; Yamaguchi, N.; Tamano, T.

    2001-07-01

    A grazing incidence flat-field soft X-ray (20-350 Å) spectrograph was constructed and applied for impurity diagnostics in the GAMMA 10 fusion plasma. The spectrograph consisted of a limited height entrance slit, an aberration-corrected concave grating, a microchannel-plate intensified detector and an instant camera/a high speed solid state camera. An absolute calibration experiment for the SX spectrograph was performed at the Photon Factory in the High Energy Accelerator Research Organization with monitoring the incident synchrotron beam intensity by using an absolutely calibrated XUV silicon photodiode. From the results of absolute calibration of the spectrograph, the radiation loss from the plasma was obtained.

  5. Absolute calibration of space-resolving soft X-ray spectrograph for plasma diagnostics

    CERN Document Server

    Yoshikawa, M; Kawamori, E; Watanabe, Y; Watabe, C; Yamaguchi, N; Tamano, T

    2001-01-01

    A grazing incidence flat-field soft X-ray (20-350 A) spectrograph was constructed and applied for impurity diagnostics in the GAMMA 10 fusion plasma. The spectrograph consisted of a limited height entrance slit, an aberration-corrected concave grating, a microchannel-plate intensified detector and an instant camera/a high speed solid state camera. An absolute calibration experiment for the SX spectrograph was performed at the Photon Factory in the High Energy Accelerator Research Organization with monitoring the incident synchrotron beam intensity by using an absolutely calibrated XUV silicon photodiode. From the results of absolute calibration of the spectrograph, the radiation loss from the plasma was obtained.

  6. Absolute vacuum ultraviolet flux in inductively coupled plasmas and chemical modifications of 193 nm photoresist

    Science.gov (United States)

    Titus, M. J.; Nest, D.; Graves, D. B.

    2009-04-01

    Vacuum ultraviolet (VUV) photons in plasma processing systems are known to alter surface chemistry and may damage gate dielectrics and photoresist. We characterize absolute VUV fluxes to surfaces exposed in an inductively coupled argon plasma, 1-50 mTorr, 25-400 W, using a calibrated VUV spectrometer. We also demonstrate an alternative method to estimate VUV fluence in an inductively coupled plasma (ICP) reactor using a chemical dosimeter-type monitor. We illustrate the technique with argon ICP and xenon lamp exposure experiments, comparing direct VUV measurements with measured chemical changes in 193 nm photoresist-covered Si wafers following VUV exposure.

  7. Absolute parametric instability of low-frequency waves in a 2D nonuniform anisotropic warm plasma

    Indian Academy of Sciences (India)

    N G Zaki

    2010-05-01

    Using the separation method, absolute parametric instability (API) of electrostatic waves in a magnetized pumped warm plasma is investigated. In this case the effect of static strong magnetic field is considered. The problem of strong magnetic field is solved in two-dimensional (2D) nonuniform plane plasma. Equations which describe the spatial part of the electric potential are obtained. Also, the growth rates and conditions of the parametric instability for periodic and aperiodic cases are obtained. It is found that the spatial nonuniformity of the plasma exerts a stabilizing effect on the API. It is shown that the growth rates of periodic and aperiodic API in warm plasma are less when compared to that in cold plasma.

  8. Relative and absolute reliability of measures of linoleic acid-derived oxylipins in human plasma.

    Science.gov (United States)

    Gouveia-Figueira, Sandra; Bosson, Jenny A; Unosson, Jon; Behndig, Annelie F; Nording, Malin L; Fowler, Christopher J

    2015-09-01

    Modern analytical techniques allow for the measurement of oxylipins derived from linoleic acid in biological samples. Most validatory work has concerned extraction techniques, repeated analysis of aliquots from the same biological sample, and the influence of external factors such as diet and heparin treatment upon their levels, whereas less is known about the relative and absolute reliability of measurements undertaken on different days. A cohort of nineteen healthy males were used, where samples were taken at the same time of day on two occasions, at least 7 days apart. Relative reliability was assessed using Lin's concordance correlation coefficients (CCC) and intraclass correlation coefficients (ICC). Absolute reliability was assessed by Bland-Altman analyses. Nine linoleic acid oxylipins were investigated. ICC and CCC values ranged from acceptable (0.56 [13-HODE]) to poor (near zero [9(10)- and 12(13)-EpOME]). Bland-Altman limits of agreement were in general quite wide, ranging from ±0.5 (12,13-DiHOME) to ±2 (9(10)-EpOME; log10 scale). It is concluded that relative reliability of linoleic acid-derived oxylipins varies between lipids with compounds such as the HODEs showing better relative reliability than compounds such as the EpOMEs. These differences should be kept in mind when designing and interpreting experiments correlating plasma levels of these lipids with factors such as age, body mass index, rating scales etc.

  9. Sulfur-based absolute quantification of proteins using isotope dilution inductively coupled plasma mass spectrometry

    Science.gov (United States)

    Lee, Hyun-Seok; Heun Kim, Sook; Jeong, Ji-Seon; Lee, Yong-Moon; Yim, Yong-Hyeon

    2015-10-01

    An element-based reductive approach provides an effective means of realizing International System of Units (SI) traceability for high-purity biological standards. Here, we develop an absolute protein quantification method using double isotope dilution (ID) inductively coupled plasma mass spectrometry (ICP-MS) combined with microwave-assisted acid digestion for the first time. We validated the method and applied it to certify the candidate protein certified reference material (CRM) of human growth hormone (hGH). The concentration of hGH was determined by analysing the total amount of sulfur in hGH. Next, the size-exclusion chromatography method was used with ICP-MS to characterize and quantify sulfur-containing impurities. By subtracting the contribution of sulfur-containing impurities from the total sulfur content in the hGH CRM, we obtained a SI-traceable certification value. The quantification result obtained with the present method based on sulfur analysis was in excellent agreement with the result determined via a well-established protein quantification method based on amino acid analysis using conventional acid hydrolysis combined with an ID liquid chromatography-tandem mass spectrometry. The element-based protein quantification method developed here can be generally used for SI-traceable absolute quantification of proteins, especially pure-protein standards.

  10. Absolute calibration of TFTR neutron detectors for D-T plasma operation

    Energy Technology Data Exchange (ETDEWEB)

    Jassby, D.L.; Johnson, L.C.; Roquemore, A.L.; Strachan, J.D.; Johnson, D.W.; Medley, S.S.; Young, K.M. [Princeton Univ., NJ (United States). Plasma Physics Lab.; Barnes, C.W. [Los Alamos National Lab., NM (United States)

    1995-03-01

    The two most sensitive TFTR fission-chamber detectors were absolutely calibrated in situ by a D-T neutron generator ({approximately}5 {times} 10{sup 7} n/s) rotated once around the torus in each direction, with data taken at about 45 positions. The combined uncertainty for determining fusion neutron rates, including the uncertainty in the total neutron generator output ({plus_minus}9%), counting statistics, the effect of coil coolant, detector stability, cross-calibration to the current mode or log Campbell mode and to other fission chambers, and plasma position variation, is about {plus_minus}13%. The NE-451 (ZnS) scintillators and {sup 4}He proportional counters that view the plasma in up to 10 collimated sightlines were calibrated by scanning. the neutron generator radially and toroidally in the horizontal midplane across the flight tubes of 7 cm diameter. Spatial integration of the detector responses using the calibrated signal per unit chord-integrated neutron emission gives the global neutron source strength with an overall uncertainty of {plus_minus}14% for the scintillators and {plus_minus}15% for the {sup 4}He counters.

  11. Absolute Intensities of the Vacuum Ultraviolet Spectra in a Metal-Etch Plasma Processing Discharge

    Energy Technology Data Exchange (ETDEWEB)

    Aragon, B.P.; Blain, M.G.; Hamilton, T.W.; Jarecki, R.L.; Woodworth, J.R.

    1998-12-09

    In this paper we report absolute intensities of vacuum ultraviolet and near ultraviolet emission lines (4.8 eV to 18 eV ) for aluminum etching discharges in an inductively coupled plasma reactor. We report line intensities as a function of wafer type, pressure, gas mixture and rf excitation level. IrI a standard aluminum etching mixture containing C12 and BC13 almost all the light emitted at energies exceeding 8.8 eV was due to neutral atomic chlorine. Optical trapping of the WV radiation in the discharge complicates calculations of VUV fluxes to the wafer. However, we see total photon fluxes to the wailer at energies above 8.8 eV on the order of 4 x 1014 photons/cm2sec with anon- reactive wafer and 0.7 x 10 `4 photons/cm2sec with a reactive wtier. The maj ority of the radiation observed was between 8.9 and 9.3 eV. At these energies, the photons have enough energy to create electron-hole pairs in Si02, but may penetrate up to a micron into the Si02 before being absorbed. Relevance of these measurements to vacuum-W photon-induced darnage of Si02 during etching is discussed.

  12. Absolute production rate measurements of nitric oxide by an atmospheric pressure plasma jet (APPJ)

    Energy Technology Data Exchange (ETDEWEB)

    Pipa, A V; Bindemann, T; Foest, R; Kindel, E; Roepcke, J; Weltmann, K-D [Leibniz-Institut fuer Plasmaforschung and Technologie e.V. (INP), Felix-Hausdorff Strasse 2, D-17489 Greifswald (Germany)], E-mail: foest@inp-greifswald.de

    2008-10-07

    Tunable diode laser absorption spectroscopy (TDLAS) has been applied to measure the absolute production rate of NO molecules in the gas phase of an atmospheric pressure plasma jet (APPJ) operating at rf (13.56 MHz) in argon with small (up to 1%) admixtures of air. The resulting NO production rates were found to be in the range (0.1-80) x 10{sup -3} sccm or (0.05-35) x 10{sup 18} molecules s{sup -1} depending on the experimental conditions. Maximum rates were obtained at 0.2% air. For TDLAS measurements the APPJ was arranged inside an astigmatic multi-pass cell of Herriott type with 100 m absorption length. The insertion into a closed volume differs slightly from the normal, open operation with the jet propagating freely into air. Therefore, the measuring results are compared with optical emission of the open jet to verify equivalent experimental conditions. The dependence of the optical emission of NO (237 nm) on power and gas mixture has been measured. The similar shape of the dependence of absorption and emission signals gives evidence that the comparability of experimental conditions is sufficiently satisfied. It is concluded that the NO production rate of the APPJ in ambient air can be characterized using TDLAS and provides reliable results in spite of differing experimental conditions due to the set-up.

  13. Diagnosis of Ultrafast Laser-Heated Metal Surfaces and Plasma Expansion with Absolute Displacement Interferometry

    Science.gov (United States)

    Rodriguez, G.; Clarke, S. A.; Taylor, A. J.; Forsman, A.

    2004-07-01

    We report on the development of a novel technique to measure the critical surface displacement in intense, ultrashort, laser-solid target experiments. Determination of the critical surface position is important for understanding near solid density plasma dynamics and transport from warm dense matter systems, and for diagnosing short scale length plasma expansion and hydrodynamic surface motion from short pulse, laser-heated, solid targets. Instead of inferring critical surface motion from spectral power shifts using a time-delayed probe pulse or from phase shifts using ultrafast pump-probe frequency domain interferometry (FDI), this technique directly measures surface displacement using a single ultrafast laser heating pulse. Our technique is based on an application of a Michelson Stellar interferometer to microscopic rather than stellar scales, and we report plasma scale length motion as small as 10 nm. We will present results for motion of plasmas generated from several target materials (Au, Al, Au on CH plastic) for a laser pulse intensity range from 1011 to 1016 W/cm2. Varying both, the pulse duration and the pulse energy, explores the dependence of the expansion mechanism on the energy deposited and on the peak intensity. Comparisons with hydrocodes reveal the applicability of hydrodynamic models.

  14. Easy Absolute Values? Absolutely

    Science.gov (United States)

    Taylor, Sharon E.; Mittag, Kathleen Cage

    2015-01-01

    The authors teach a problem-solving course for preservice middle-grades education majors that includes concepts dealing with absolute-value computations, equations, and inequalities. Many of these students like mathematics and plan to teach it, so they are adept at symbolic manipulations. Getting them to think differently about a concept that they…

  15. Preliminary investigation of plasma levels of sex hormones and human growth factor(s, and P300 latency as correlates to cognitive decline as a function of gender

    Directory of Open Access Journals (Sweden)

    Kerner Mallory M

    2009-07-01

    Full Text Available Abstract Background Aging is marked by declines in levels of many sex hormones and growth factors, as well as in cognitive function. The P300 event-related potential has been established as a predictor of cognitive decline. We decided to determine if this measure, as well as 2 standard tests of memory and attention, may be correlated with serum levels of sex hormones and growth factors, and if there are any generalizations that could be made based on these parameters and the aging process. Findings In this large clinically based preliminary study several sex-stratified associations between hormone levels and cognition were observed, including (1 for males aged 30 to 49, both IGF-1 and IGFBP-3 significantly associated negatively with prolonged P300 latency; (2 for males aged 30 to 49, the spearman correlation between prolonged P300 latency and low free testosterone was significant; (3 for males aged 60 to 69, there was a significant negative correlation between P300 latency and DHEA levels; (4 for females aged 50 to 59 IGFBP-3 significantly associated negatively with prolonged P300 latency; (5 for females at all age periods, estrogen and progesterone were uncorrelated with P300 latency; and (6 for females aged 40 to 69, there was significant negative correlation between DHEA levels and P300 latency. Moreover there were no statistically significant correlations between any hormone and Wechsler Memory Scale-III (WMS-111. However, in females, there was a significant positive correlation between estrogen levels and the number of Attention Deficit Disorder (ADD complaints. Conclusion Given certain caveats including confounding factors involving psychiatric and other chronic diseases as well as medications, the results may still have important value. If these results could be confirmed in a more rigorously controlled investigation, it may have important value in the diagnosis, prevention and treatment of cognitive impairments and decline.

  16. A novel method to determine the electron temperature and density from the absolute intensity of line and continuum emission: application to atmospheric microwave induced Ar plasmas

    Science.gov (United States)

    Iordanova, E.; Palomares, J. M.; Gamero, A.; Sola, A.; van der Mullen, J. J. A. M.

    2009-08-01

    An absolute intensity measurement (AIM) technique is presented that combines the absolute measurements of the line and the continuum emitted by strongly ionizing argon plasmas. AIM is an iterative combination of the absolute line intensity-collisional radiative model (ALI-CRM) and the absolute continuum intensity (ACI) method. The basis of ALI-CRM is that the excitation temperature T13 determined by the method of ALI is transformed into the electron temperature Te using a CRM. This gives Te as a weak function of electron density ne. The ACI method is based on the absolute value of the continuum radiation and determines the electron density in a way that depends on Te. The iterative combination gives ne and Te. As a case study the AIM method is applied to plasmas created by torche à injection axiale (TIA) at atmospheric pressure and fixed frequency at 2.45 GHz. The standard operating settings are a gas flow of 1 slm and a power of 800 W; the measurements have been performed at a position of 1 mm above the nozzle. With AIM we found an electron temperature of 1.2 eV and electron density values around 1021 m-3. There is not much dependence of these values on the plasma control parameters (power and gas flow). From the error analysis we can conclude that the determination of Te is within 7% and thus rather accurate but comparison with other studies shows strong deviations. The ne determination comes with an error of 40% but is in reasonable agreement with other experimental results.

  17. Time-resolved absolute measurements by electro-optic effect of giant electromagnetic pulses due to laser-plasma interaction in nanosecond regime

    Science.gov (United States)

    Consoli, F.; de Angelis, R.; Duvillaret, L.; Andreoli, P. L.; Cipriani, M.; Cristofari, G.; di Giorgio, G.; Ingenito, F.; Verona, C.

    2016-06-01

    We describe the first electro-optical absolute measurements of electromagnetic pulses (EMPs) generated by laser-plasma interaction in nanosecond regime. Laser intensities are inertial-confinement-fusion (ICF) relevant and wavelength is 1054 nm. These are the first direct EMP amplitude measurements with the detector rather close and in direct view of the plasma. A maximum field of 261 kV/m was measured, two orders of magnitude higher than previous measurements by conductive probes on nanosecond regime lasers with much higher energy. The analysis of measurements and of particle-in-cell simulations indicates that signals match the emission of charged particles detected in the same experiment, and suggests that anisotropic particle emission from target, X-ray photoionization and charge implantation on surfaces directly exposed to plasma, could be important EMP contributions. Significant information achieved on EMP features and sources is crucial for future plants of laser-plasma acceleration and inertial-confinement-fusion and for the use as effective plasma diagnostics. It also opens to remarkable applications of laser-plasma interaction as intense source of RF-microwaves for studies on materials and devices, EMP-radiation-hardening and electromagnetic compatibility. The demonstrated extreme effectivity of electric-fields detection in laser-plasma context by electro-optic effect, leads to great potential for characterization of laser-plasma interaction and generated Terahertz radiation.

  18. P300 latency indexes nitrogen narcosis.

    Science.gov (United States)

    Fowler, B; Pogue, J; Porlier, G

    1990-03-01

    This experiment investigated the effects of nitrogen narcosis on reaction time (RT) and P300 latency and amplitude. Ten subjects breathed either air or a non-narcotic 20% oxygen-80% helium (heliox) mixture in a hyperbaric chamber at 6.5, 8.3 and 10 atmospheres absolute (ATA). The subjects responded under controlled accuracy conditions to visually presented male or female names in an oddball paradigm. Single-trial analysis revealed a strong relationship between RT and P300 latency, both of which were slowed in a dose-related manner by hyperbaric air but not by heliox. A clear-cut dose-response relationship could not be established for P300 amplitude. These results indicate that P300 latency indexes nitrogen narcosis and are interpreted as support for the slowed processing model of inert gas narcosis.

  19. Comparison of simulation to absolute X-ray emission of CH plasma created with the Nike laser

    Science.gov (United States)

    Busquet, M.; Weaver, J. L.; Colombant, D. G.; Mostovych, A. N.; Feldman, U.; Klapisch, M.; Seely, J. F.; Holland, G.

    2006-06-01

    The Nike laser group at the Naval Research Laboratory has an ongoing effort to improve and benchmark the radiation hydrodynamic simulations used to develop pellet designs for inertial confinement fusion. A new postprocessor, Virtual Spectro, has been added to the FAST code suite for detailed simulation of non-LTE spectra, including radiation transport effects and Stark line profile. This new combination enhances our ability to predict the absolute emission of soft x-rays. An absolutely calibrated transmission grating spectrometer and a high resolution grazing incidence spectrometer have been used to collect time integrated and time resolved spectra emitted by CH targets irradiated at laser intensities of ˜10 TW/cm^2. Comparison between these observations and simulations using Virtual Spectro demonstrates excellent agreement (within factor of ˜1.5) for the absolute emission.

  20. Comparison of simulation to absolute X-ray emission of CH plasma created with the Nike laser

    Energy Technology Data Exchange (ETDEWEB)

    Busquet, M.; Feldman, U.; Klapisch, M. [ARTEP, Inc., Ellicott City, Maryland (contractor to NRL) (United States); Weaver, J.L.; Colombant, D.G.; Mostovych, A.N. [Naval Research Laboratory, Plasma Physics Division, Washington, DC (United States); Seely, J.F. [Naval Research Laboratory, Space Science Division, Washington, DC (United States); Holland, G. [SFA, Inc., Landover, Maryland (contractor to NRL) (United States)

    2006-06-15

    The Nike laser group at the Naval Research Laboratory has an ongoing effort to improve and benchmark the radiation hydrodynamic simulations used to develop pellet designs for inertial confinement fusion. A new post-processor, Virtual Spectro, has been added to the FAST code suite for detailed simulation of non-local thermodynamical equilibrium (non-LTE) spectra, including radiation transport effects and Stark line profile. This new combination enhances our ability to predict the absolute emission of soft X-rays. An absolutely calibrated transmission grating spectrometer and a high resolution grazing incidence spectrometer have been used to collect time integrated and time resolved spectra emitted by CH targets irradiated at laser intensities of about 10 TW/cm{sup 2}. Comparison between these observations and simulations using Virtual Spectro demonstrates excellent agreement (within factor of about 1.5) for the absolute emission. (authors)

  1. On the opportunity of spectroscopic determination of absolute atomic densities in non-equilibrium plasmas from measured relative intensities within resonance multiplets distorted by self-absorption

    CERN Document Server

    Lavrov, B P

    2007-01-01

    The opportunities of the application of the recently proposed approach in optical emission spectroscopy of non-equilibrium plasmas have been studied. The approach consists of several methods of the determination of {\\em absolute} particle densities of atoms from measured {\\em relative} intensities within resonance multiplets distorted by self-absorption. All available spectroscopic data concerning resonance spectral lines of atoms having multiplet ground states from boron up to gallium were analyzed. It is found that in the case of C, O, F, S and Cl atoms an application of the methods needs VUV technique, while densities of B, Al, Si, Sc, Ti, V, Co, Ni, Ga atoms may be obtained by means of the intensity measurements in UV and visible parts of emission spectra suitable for ordinary spectrometers used for optical diagnostics and monitoring of non-equilibrium plasmas including industrial plasma technologies.

  2. Absolute densities of Cu, Zn, Sn, and S atoms in magnetron sputtering plasmas employing a Cu2ZnSnS4 target

    Science.gov (United States)

    Nafarizal, Nayan; Sasaki, Koichi

    2016-07-01

    Absolute densities of Cu, Zn, Sn, and S atoms in magnetron sputtering plasmas were measured by ultraviolet absorption spectroscopy and vacuum ultraviolet absorption spectroscopy. A stoichiometric Cu2ZnSnS4 (CZTS) target was used in this work. It was found that, at various Ar pressures, the S density ranged between (2-8) × 1010 cm-3, the Cu and Sn densities ranged between (0.6-3) × 1010 cm-3, and the Zn density ranged between (2-3) × 109 cm-3. The effective depositing flux, which was evaluated from the absolute densities and the sticking probabilities, was comparable with that evaluated from the deposition rate of the CZTS film. However, the composition ratio of Cu, Zn, Sn, and S in the gas phase deviated from the ideal stoichiometry of CZTS. We discussed the possible mechanisms for the difference among the element compositions of the target, the deposited film, and the gas-phase densities.

  3. Absolute advantage

    NARCIS (Netherlands)

    J.G.M. van Marrewijk (Charles)

    2008-01-01

    textabstractA country is said to have an absolute advantage over another country in the production of a good or service if it can produce that good or service using fewer real resources. Equivalently, using the same inputs, the country can produce more output. The concept of absolute advantage can a

  4. Absolute number densities of helium metastable atoms determined by atomic absorption spectroscopy in helium plasma-based discharges used as ambient desorption/ionization sources for mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Reininger, Charlotte; Woodfield, Kellie [Brigham Young University, Department of Chemistry and Biochemistry, Provo, UT 84602 (United States); Keelor, Joel D.; Kaylor, Adam; Fernández, Facundo M. [Georgia Institute of Technology, School of Chemistry and Biochemistry, Atlanta, GA 30332 (United States); Farnsworth, Paul B., E-mail: paul_farnsworth@byu.edu [Brigham Young University, Department of Chemistry and Biochemistry, Provo, UT 84602 (United States)

    2014-10-01

    The absolute number densities of helium atoms in the 2s {sup 3}S{sub 1} metastable state were determined in four plasma-based ambient desorption/ionization sources by atomic absorption spectroscopy. The plasmas included a high-frequency dielectric barrier discharge (HF-DBD), a low temperature plasma (LTP), and two atmospheric-pressure glow discharges, one with AC excitation and the other with DC excitation. Peak densities in the luminous plumes downstream from the discharge capillaries of the HF-DBD and the LTP were 1.39 × 10{sup 12} cm{sup −3} and 0.011 × 10{sup 12} cm{sup −3}, respectively. Neither glow discharge produced a visible afterglow, and no metastable atoms were detected downstream from the capillary exits. However, densities of 0.58 × 10{sup 12} cm{sup −3} and 0.97 × 10{sup 12} cm{sup −3} were measured in the interelectrode regions of the AC and DC glow discharges, respectively. Time-resolved measurements of metastable atom densities revealed significant random variations in the timing of pulsed absorption signals with respect to the voltage waveforms applied to the discharges. - Highlights: • We determine He metastable number densities for four plasma types • The highest number densities were observed in a dielectric barrier discharge • No helium metastable atoms were observed downstream from the exits of glow discharges.

  5. Absolute atomic oxygen density measurements for nanosecond-pulsed atmospheric-pressure plasma jets using two-photon absorption laser-induced fluorescence spectroscopy

    Science.gov (United States)

    Jiang, C.; Carter, C.

    2014-12-01

    Nanosecond-pulsed plasma jets that are generated under ambient air conditions and free from confinement of electrodes have become of great interest in recent years due to their promising applications in medicine and dentistry. Reactive oxygen species that are generated by nanosecond-pulsed, room-temperature non-equilibrium He-O2 plasma jets among others are believed to play an important role during the bactericidal or sterilization processes. We report here absolute measurements of atomic oxygen density in a 1 mm-diameter He/(1%)O2 plasma jet at atmospheric pressure using two-photon absorption laser-induced fluorescence spectroscopy. Oxygen number density on the order of 1013 cm-3 was obtained in a 150 ns, 6 kV single-pulsed plasma jet for an axial distance up to 5 mm above the device nozzle. Temporally resolved O density measurements showed that there are two maxima, separated in time by 60-70 µs, and a total pulse duration of 260-300 µs. Electrostatic modeling indicated that there are high-electric-field regions near the nozzle exit that may be responsible for the observed temporal behavior of the O production. Both the field-distribution-based estimation of the time interval for the O number density profile and a pulse-energy-dependence study confirmed that electric-field-dependent, direct and indirect electron-induced processes play important roles for O production.

  6. Development of a Time Domain Radio Frequency Plasma Impedance Probe For Measurement of Absolute Electron Density and Electron Neutral Collision Frequency

    Science.gov (United States)

    Spencer, E. A.

    2014-12-01

    We describe the development of a Time Domain Plasma Impedance Probe for the measurement of plasma properties in the ionosphere. It is being designed and developed to fly on cubesat platforms. The new instrument will be capable of making measurements of absolute electron density and electron neutral collision frequency at temporal and spatial resolutions not previously attained. A single measurement can be made in a time as short as 50 microseconds, which yields a spatial resolution of 0.35 meters for a satellite orbital velocity of 7 km/s. By averaging over 100 samples we expect an average spatial resolution of 35 meters. The method essentially consists of applying a small amplitude time limited voltage signal into a probe and measuring the resulting current response. The electron resonant frequencies of interest in the ionosphere are between are typically between 100 kHz and 20 MHz, which sets the required bandwidth. The new time domain method will present a significant improvement over the frequency domain method currently in use. The RF impedance probe has a distinct advantage over other methods used to measure plasma properties, in that it's measurements are not strongly affected by spacecraft charging effects that contaminate measurements made in the plasma environment. We will demonstrate the effectiveness of the instrument using data from sounding rocket missions, give details of the new instrument methodology, and suggest some possible areas of application of the method to measuring space plasmas. The difficulties associated with performing the measurements in a cubesat platform, and subsequently interpreting the measurements, will also be presented.

  7. Absolute number densities of helium metastable atoms determined by atomic absorption spectroscopy in helium plasma-based discharges used as ambient desorption/ionization sources for mass spectrometry

    Science.gov (United States)

    Reininger, Charlotte; Woodfield, Kellie; Keelor, Joel D.; Kaylor, Adam; Fernández, Facundo M.; Farnsworth, Paul B.

    2014-10-01

    The absolute number densities of helium atoms in the 2s 3S1 metastable state were determined in four plasma-based ambient desorption/ionization sources by atomic absorption spectroscopy. The plasmas included a high-frequency dielectric barrier discharge (HF-DBD), a low temperature plasma (LTP), and two atmospheric-pressure glow discharges, one with AC excitation and the other with DC excitation. Peak densities in the luminous plumes downstream from the discharge capillaries of the HF-DBD and the LTP were 1.39 × 1012 cm- 3 and 0.011 × 1012 cm- 3, respectively. Neither glow discharge produced a visible afterglow, and no metastable atoms were detected downstream from the capillary exits. However, densities of 0.58 × 1012 cm- 3 and 0.97 × 1012 cm- 3 were measured in the interelectrode regions of the AC and DC glow discharges, respectively. Time-resolved measurements of metastable atom densities revealed significant random variations in the timing of pulsed absorption signals with respect to the voltage waveforms applied to the discharges.

  8. An ensemble average method to estimate absolute TEC using radio beacon-based differential phase measurements: Applicability to regions of large latitudinal gradients in plasma density

    Science.gov (United States)

    Thampi, Smitha V.; Bagiya, Mala S.; Chakrabarty, D.; Acharya, Y. B.; Yamamoto, M.

    2014-12-01

    A GNU Radio Beacon Receiver (GRBR) system for total electron content (TEC) measurements using 150 and 400 MHz transmissions from Low-Earth Orbiting Satellites (LEOS) is fabricated in house and made operational at Ahmedabad (23.04°N, 72.54°E geographic, dip latitude 17°N) since May 2013. This system receives the 150 and 400 MHz transmissions from high-inclination LEOS. The first few days of observations are presented in this work to bring out the efficacy of an ensemble average method to convert the relative TECs to absolute TECs. This method is a modified version of the differential Doppler-based method proposed by de Mendonca (1962) and suitable even for ionospheric regions with large spatial gradients. Comparison of TECs derived from a collocated GPS receiver shows that the absolute TECs estimated by this method are reliable estimates over regions with large spatial gradient. This method is useful even when only one receiving station is available. The differences between these observations are discussed to bring out the importance of the spatial differences between the ionospheric pierce points of these satellites. A few examples of the latitudinal variation of TEC during different local times using GRBR measurements are also presented, which demonstrates the potential of radio beacon measurements in capturing the large-scale plasma transport processes in the low-latitude ionosphere.

  9. Estimating latency from inhibitory input

    DEFF Research Database (Denmark)

    Levakova, Marie; Ditlevsen, Susanne; Lansky, Petr

    2014-01-01

    to the stimulus by an increase in the firing rate. We focus on the estimation of the response latency in the case of inhibitory stimuli. Models used in this paper represent two different descriptions of response latency. We consider either the latency to be constant across trials or to be a random variable......Stimulus response latency is the time period between the presentation of a stimulus and the occurrence of a change in the neural firing evoked by the stimulation. The response latency has been explored and estimation methods proposed mostly for excitatory stimuli, which means that the neuron reacts....... In the case of random latency, special attention is given to models with selective interaction. The aim is to propose methods for estimation of the latency or the parameters of its distribution. Parameters are estimated by four different methods: method of moments, maximum-likelihood method, a method...

  10. Absolute Summ

    Science.gov (United States)

    Phillips, Alfred, Jr.

    Summ means the entirety of the multiverse. It seems clear, from the inflation theories of A. Guth and others, that the creation of many universes is plausible. We argue that Absolute cosmological ideas, not unlike those of I. Newton, may be consistent with dynamic multiverse creations. As suggested in W. Heisenberg's uncertainty principle, and with the Anthropic Principle defended by S. Hawking, et al., human consciousness, buttressed by findings of neuroscience, may have to be considered in our models. Predictability, as A. Einstein realized with Invariants and General Relativity, may be required for new ideas to be part of physics. We present here a two postulate model geared to an Absolute Summ. The seedbed of this work is part of Akhnaton's philosophy (see S. Freud, Moses and Monotheism). Most important, however, is that the structure of human consciousness, manifest in Kenya's Rift Valley 200,000 years ago as Homo sapiens, who were the culmination of the six million year co-creation process of Hominins and Nature in Africa, allows us to do the physics that we do. .

  11. Unsupervised, low latency

    Directory of Open Access Journals (Sweden)

    Jayaram Raghuram

    2014-07-01

    Full Text Available We propose a method for detecting anomalous domain names, with focus on algorithmically generated domain names which are frequently associated with malicious activities such as fast flux service networks, particularly for bot networks (or botnets, malware, and phishing. Our method is based on learning a (null hypothesis probability model based on a large set of domain names that have been white listed by some reliable authority. Since these names are mostly assigned by humans, they are pronounceable, and tend to have a distribution of characters, words, word lengths, and number of words that are typical of some language (mostly English, and often consist of words drawn from a known lexicon. On the other hand, in the present day scenario, algorithmically generated domain names typically have distributions that are quite different from that of human-created domain names. We propose a fully generative model for the probability distribution of benign (white listed domain names which can be used in an anomaly detection setting for identifying putative algorithmically generated domain names. Unlike other methods, our approach can make detections without considering any additional (latency producing information sources, often used to detect fast flux activity. Experiments on a publicly available, large data set of domain names associated with fast flux service networks show encouraging results, relative to several baseline methods, with higher detection rates and low false positive rates.

  12. [Long-latency auditory evoked potentials in cochlear implants].

    Science.gov (United States)

    Mata, J J; Jiménez, J M; Pérez, J; Postigo, A; Roldán, B

    1999-01-01

    Cortical evoked potentials were evaluated in patients with cochlear implants. In a group of 8 adults of different ages, the lingual state before implantation and during rehabilitation were evaluated. Using cortical evoked potentials, the results of the P300 wave in response to two tones, one frequent (1,000 Hz) and the other infrequent (2,000 Hz), presented at 70 and 80 dB HL were studied. Results were analyzed and compared in relation to locutive state, rehabilitation stage, and intensity of stimulus. Absolute latencies did not differ significantly. However, latency values in relation to reaction time were significantly longer in prelingual than in postlingual patients (p test). The results confirmed the normality of central cognitive processes in patients with cochlear implants in objective assessment of P300 latency. The results suggest differences between prelingual and postlingual patients in relation to central signal processing.

  13. Development of an RNA Assay to Assess HIV I Latency

    Science.gov (United States)

    1993-01-10

    current study is limited to examining cellular RNAs rather than free genomic RNA in the plasma. Ottmann and colleagues demonstrated HIV-1 genomic RNA in 95...aberrant pattern of viral RNA expression: a molecular model for latency. Cell 1990; 61:1271-1276. 25 Ottmann M, Innocenti P, Tenadey M, Micoud M

  14. Teaching Absolute Value Meaningfully

    Science.gov (United States)

    Wade, Angela

    2012-01-01

    What is the meaning of absolute value? And why do teachers teach students how to solve absolute value equations? Absolute value is a concept introduced in first-year algebra and then reinforced in later courses. Various authors have suggested instructional methods for teaching absolute value to high school students (Wei 2005; Stallings-Roberts…

  15. Isobaric Tags for Relative and Absolute Quantification-based Comparative Proteomics Reveals the Features of Plasma Membrane-Associated Proteomes of Pollen Grains and Pollen Tubes from Lilium davidii

    Institute of Scientific and Technical Information of China (English)

    Bing Han; Sixue Chen; Shaojun Dai; Ning Yang; Tai Wang

    2010-01-01

    Mature pollen grains (PGs) from most plant species are metabolically quiescent. However, once pollinated onto stigma, they quickly hydrate and germinate. APG can give rise to a vegetative cell-derived polarized pollen tube (PT), which represents a specialized polar cell. The polarized PT grows by the tip and requires interaction of different signaling molecules localized in the apical plasma membrane and active membrane trafficking. The mechanisms underlying the interaction and membrane trafficking are not well understood. In this work, we purified PG and PT plasma-membrane vesicles from Lilium davidii Duch. using the aqueous two-phase partition technique, then enriched plasma membrane proteins by using Brij58 and KCl to remove loosely bound contaminants. We identified 223 integral and membrane-associated proteins in the plasma membrane of PGs and PTs by using isobaric tags for relative and absolute quantification (iTRAQ) and 2-D high-performance liquid chromatography-tandem mass spectrometry. More than 68% of the proteins have putative transmembrane domains and/or lipid-modified motifs. Proteins involved in signal transduction, membrane trafficking and transport are predominant in the plasma-membrane proteome. We revealed most components of the clathrin-dependent endocytosis pathway. Statistical analysis revealed 14 proteins differentially expressed in the two development stages: in PTs, six upregulated and eight downregulated are mainly involved in signaling, transport and membrane trafficking. These results provide novel insights into polarized PT growth.

  16. Identification of noisy response latency

    DEFF Research Database (Denmark)

    Tamborrino, Massimiliano; Ditlevsen, Susanne; Lansky, Petr

    2012-01-01

    be highly unreliable, unless the background signal is accounted for in the analysis. In fact, if the background signal is ignored, however small it is compared to the response and however large the delay is, the estimate of the time delay will go to zero for any reasonable estimator when increasing...... the number of observations. Here we propose a unified concept of response latency identification in event data corrupted by a background signal. It is done in the context of information transfer within a neural system, more specifically on spike trains from single neurons. The estimators are compared...

  17. Absolute OH and O radical densities in effluent of a He/H2O micro-scaled atmospheric pressure plasma jet

    Science.gov (United States)

    Benedikt, J.; Schröder, D.; Schneider, S.; Willems, G.; Pajdarová, A.; Vlček, J.; Schulz-von der Gathen, V.

    2016-08-01

    The effluent of a micro-scaled atmospheric pressure plasma jet (μ-APPJ) operated in helium with admixtures of water vapor (≲ {{10}4} ppm) has been analyzed by means of cavity ring-down laser absorption spectroscopy and molecular beam mass spectrometry to measure hydroxyl (OH) radical densities, and by two-photon absorption laser-induced fluorescence spectroscopy to measure atomic oxygen (O) densities. Additionally, the performance of the bubbler as a source of water vapor in the helium feed gas has been carefully characterized and calibrated. The largest OH and O densities in the effluent of 2× {{10}14}~\\text{c}{{\\text{m}}-3} and 3.2× {{10}13}~\\text{c}{{\\text{m}}-3} , respectively, have been measured at around 6000 ppm. The highest selectivity is reached around 1500 ppm, where the OH density is at  ∼63% of its maximum value and is 14 times larger than the O density. The measured density profiles and distance variations are compared to the results of a 2D axially symmetric fluid model of species transport and reaction kinetics in the plasma effluent. It is shown that the main loss of OH radicals in the effluent is their mutual reaction. In the case of O, reactions with other species than OH also have to be considered to explain the density decay in the effluent. The results presented here provide additional information for understanding the plasma-chemical processes in non-equilibrium atmospheric pressure plasmas. They also open the way to applying μ-APPJ with He/H2O as a selective source of OH radicals.

  18. Absolute nuclear material assay

    Science.gov (United States)

    Prasad, Manoj K [Pleasanton, CA; Snyderman, Neal J [Berkeley, CA; Rowland, Mark S [Alamo, CA

    2012-05-15

    A method of absolute nuclear material assay of an unknown source comprising counting neutrons from the unknown source and providing an absolute nuclear material assay utilizing a model to optimally compare to the measured count distributions. In one embodiment, the step of providing an absolute nuclear material assay comprises utilizing a random sampling of analytically computed fission chain distributions to generate a continuous time-evolving sequence of event-counts by spreading the fission chain distribution in time.

  19. Absolute number density and kinetic analysis of CF, CF{sub 2} and C{sub 2}F{sub 4} molecules in pulsed CF{sub 4}/H{sub 2} rf plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Stepanov, Sergey

    2010-04-26

    Tunable Diode Laser Absorption Spectroscopy in the mid InfraRed spectral range (IR-TDLAS) has been applied to investigate the behaviour of CF, CF{sub 2} and C{sub 2}F{sub 4} species produced in pulsed CF{sub 4}/H{sub 2} capacitively coupled radio frequency plasmas (13.56 MHz CCP). This experimental technique was shown to be suitable for temporally resolved measurements of the absolute number density of the target molecules in the studied fluorocarbon discharges. The temporal resolution of about 20..40 ms typically achieved in the standard data acquisition mode (''stream mode'') was sufficient for the real-time measurements of CF{sub 2} and C{sub 2}F{sub 4}, but not of CF whose kinetics was observed to be much faster. Therefore, a more sophisticated approach (''burst mode'') providing a temporal resolution of 0.94 ms was established and successfully applied to CF density measurements. In order to enable the TDLAS measurements of the target species, preliminary investigations on their spectroscopic data had been carried out. In particular, pure C{sub 2}F{sub 4} has been produced in laboratory by means of vacuum thermal decomposition (pyrolysis) of polytetrafluoroethylene and used as a reference gas. Therefore, an absorption structure consisting of several overlapping C{sub 2}F{sub 4} lines around 1337.11 cm{sup -1} was selected and carefully calibrated, which provided the first absolute measurements of the species by means of the applied experimental technique. The absolute number density traces measured for CF, CF{sub 2} and C{sub 2}F{sub 4} in the studied pulsed plasmas were then analysed, in which two differential balance equations were proposed for each of the species to describe their behaviour during both ''plasma on'' and ''plasma off'' phases. Analytical solutions of the balance equations were used to fit the experimental data and hence to deduce important information on the

  20. Absolute neutrino mass update

    CERN Document Server

    Päs, H; P\\"as, Heinrich; Weiler, Thomas J.

    2002-01-01

    The determination of absolute neutrino masses is crucial for the understanding of theories underlying the standard model, such as SUSY. We review the experimental prospects to determine absolute neutrino masses and the correlations among approaches, using the Delta m^2's inferred from neutrino oscillation experiments and assuming a three neutrino Universe.

  1. ABSOLUTE NEUTRINO MASSES

    DEFF Research Database (Denmark)

    Schechter, J.; Shahid, M. N.

    2012-01-01

    We discuss the possibility of using experiments timing the propagation of neutrino beams over large distances to help determine the absolute masses of the three neutrinos.......We discuss the possibility of using experiments timing the propagation of neutrino beams over large distances to help determine the absolute masses of the three neutrinos....

  2. CHRONIC DISSEMINATED HISTOPLASMOSIS WITH PROLONGED LATENCY

    Science.gov (United States)

    A case of chronic disseminated histoplasmosis in an ex-serviceman is described. Evidence is presented to support a latency period of over sixty years between acquisition of infection and clinical manifestation. This is the longest latency period for histoplasmosis described in the medical literature...

  3. Ferromagnetic particles as a rapid and robust sample preparation for the absolute quantification of seven eicosanoids in human plasma by UHPLC-MS/MS.

    Science.gov (United States)

    Suhr, Anna Catharina; Bruegel, Mathias; Maier, Barbara; Holdt, Lesca Miriam; Kleinhempel, Alisa; Teupser, Daniel; Grimm, Stefanie H; Vogeser, Michael

    2016-06-01

    We used ferromagnetic particles as a novel technique to deproteinize plasma samples prior to quantitative UHPLC-MS/MS analysis of seven eicosanoids [thromboxane B2 (TXB2), prostaglandin E2 (PGE2), PGD2, 5-hydroxyeicosatetraenoic acid (5-HETE), 11-HETE, 12-HETE, arachidonic acid (AA)]. A combination of ferromagnetic particle enhanced deproteination and subsequent on-line solid phase extraction (on-line SPE) realized quick and convenient semi-automated sample preparation-in contrast to widely used manual SPE techniques which are rather laborious and therefore impede the investigation of AA metabolism in larger patient cohorts. Method evaluation was performed according to a protocol based on the EMA guideline for bioanalytical method validation, modified for endogenous compounds. Calibrators were prepared in ethanol. The calibration curves were found to be linear in a range of 0.1-80ngmL(-1) (TXB2, PGE2, PGD2), 0.05-40ngmL(-1) (5-HETE, 11-HETE), 0.5-400ngmL(-1) (12-HETE) and 25-9800ngmL(-1) (AA). Regarding all analytes and all quality controls, the resulting precision data (inter-assay 2.6 %-15.5 %; intra-assay 2.5 %-15.1 %, expressed as variation coefficient) as well as the accuracy results (inter-assay 93.3 %-125 %; intra-assay 91.7 %-114 %) were adequate. Further experiments addressing matrix effect, recovery and robustness, yielded also very satisfying results. As a proof of principle, the newly developed LC-MS/MS assay was employed to determine the capacity of AA metabolite release after whole blood stimulation in healthy blood donors. For this purpose, whole blood specimens of 5 healthy blood donors were analyzed at baseline and after a lipopolysaccharide (LPS) induced blood cell activation. In several baseline samples some eicosanoids levels were below the Lower Limit of Quantification. However, in the stimulated samples all chosen eicosanoids (except PGD2) could be quantified. These results, in context with those obtained in validation, demonstrate the

  4. NGS Absolute Gravity Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NGS Absolute Gravity data (78 stations) was received in July 1993. Principal gravity parameters include Gravity Value, Uncertainty, and Vertical Gradient. The...

  5. Decoherence at absolute zero

    OpenAIRE

    Sinha, Supurna

    2005-01-01

    We present an analytical study of the loss of quantum coherence at absolute zero. Our model consists of a harmonic oscillator coupled to an environment of harmonic oscillators at absolute zero. We find that for an Ohmic bath, the offdiagonal elements of the density matrix in the position representation decay as a power law in time at late times. This slow loss of coherence in the quantum domain is qualitatively different from the exponential decay observed in studies of high temperature envir...

  6. Absolute biological needs.

    Science.gov (United States)

    McLeod, Stephen

    2014-07-01

    Absolute needs (as against instrumental needs) are independent of the ends, goals and purposes of personal agents. Against the view that the only needs are instrumental needs, David Wiggins and Garrett Thomson have defended absolute needs on the grounds that the verb 'need' has instrumental and absolute senses. While remaining neutral about it, this article does not adopt that approach. Instead, it suggests that there are absolute biological needs. The absolute nature of these needs is defended by appeal to: their objectivity (as against mind-dependence); the universality of the phenomenon of needing across the plant and animal kingdoms; the impossibility that biological needs depend wholly upon the exercise of the abilities characteristic of personal agency; the contention that the possession of biological needs is prior to the possession of the abilities characteristic of personal agency. Finally, three philosophical usages of 'normative' are distinguished. On two of these, to describe a phenomenon or claim as 'normative' is to describe it as value-dependent. A description of a phenomenon or claim as 'normative' in the third sense does not entail such value-dependency, though it leaves open the possibility that value depends upon the phenomenon or upon the truth of the claim. It is argued that while survival needs (or claims about them) may well be normative in this third sense, they are normative in neither of the first two. Thus, the idea of absolute need is not inherently normative in either of the first two senses.

  7. EBV latency types adopt alternative chromatin conformations.

    Directory of Open Access Journals (Sweden)

    Italo Tempera

    2011-07-01

    Full Text Available Epstein-Barr Virus (EBV can establish latent infections with distinct gene expression patterns referred to as latency types. These different latency types are epigenetically stable and correspond to different promoter utilization. Here we explore the three-dimensional conformations of the EBV genome in different latency types. We employed Chromosome Conformation Capture (3C assay to investigate chromatin loop formation between the OriP enhancer and the promoters that determine type I (Qp or type III (Cp gene expression. We show that OriP is in close physical proximity to Qp in type I latency, and to Cp in type III latency. The cellular chromatin insulator and boundary factor CTCF was implicated in EBV chromatin loop formation. Combining 3C and ChIP assays we found that CTCF is physically associated with OriP-Qp loop formation in type I and OriP-Cp loop formation in type III latency. Mutations in the CTCF binding site located at Qp disrupt loop formation between Qp and OriP, and lead to the activation of Cp transcription. Mutation of the CTCF binding site at Cp, as well as siRNA depletion of CTCF eliminates both OriP-associated loops, indicating that CTCF plays an integral role in loop formation. These data indicate that epigenetically stable EBV latency types adopt distinct chromatin architectures that depend on CTCF and mediate alternative promoter targeting by the OriP enhancer.

  8. Advanced LIGO low-latency searches

    Science.gov (United States)

    Kanner, Jonah; LIGO Scientific Collaboration, Virgo Collaboration

    2016-06-01

    Advanced LIGO recently made the first detection of gravitational waves from merging binary black holes. The signal was first identified by a low-latency analysis, which identifies gravitational-wave transients within a few minutes of data collection. More generally, Advanced LIGO transients are sought with a suite of automated tools, which collectively identify events, evaluate statistical significance, estimate source position, and attempt to characterize source properties. This low-latency effort is enabling a broad multi-messenger approach to the science of compact object mergers and other transients. This talk will give an overview of the low-latency methodology and recent results.

  9. Low Latency High Throughout Circular Asynchronous FIFO

    Institute of Scientific and Technical Information of China (English)

    XIAO Yong; ZHOU Runde

    2008-01-01

    This paper describes a circular first in first out (FIFO) and its protocols which have a very low la-tency while still maintaining high throughput. Unlike the existing serial FIFOs based on asynchronous micro-pipelines, this FIFO's cells communicate directly with the input and output ports through a common bus, which effectively eliminates the data movement from the input port to the output port, thereby reducing the latency and the power consumption. Furthermore, the latency does not increase with the number of FIFO stages. Single-track asynchronous protocols are used to simplify the FIFO controller design, with only three C-gates needed in each cell controller, which substantially reduces the area. Simulations with the TSMC 0.25 Ijm CMOS logic process show that the latency of the 4-stage FIFO is less than 581 ps and the throughput is higher than 2.2 GHz.

  10. Absolute calibration of TFTR helium proportional counters

    Energy Technology Data Exchange (ETDEWEB)

    Strachan, J.D.; Diesso, M.; Jassby, D.; Johnson, L.; McCauley, S.; Munsat, T.; Roquemore, A.L. [Princeton Univ., NJ (United States). Plasma Physics Lab.; Barnes, C.W. [Princeton Univ., NJ (United States). Plasma Physics Lab.]|[Los Alamos National Lab., NM (United States); Loughlin, M. [Princeton Univ., NJ (United States). Plasma Physics Lab.]|[JET Joint Undertaking, Abingdon (United Kingdom)

    1995-06-01

    The TFTR helium proportional counters are located in the central five (5) channels of the TFTR multichannel neutron collimator. These detectors were absolutely calibrated using a 14 MeV neutron generator positioned at the horizontal midplane of the TFTR vacuum vessel. The neutron generator position was scanned in centimeter steps to determine the collimator aperture width to 14 MeV neutrons and the absolute sensitivity of each channel. Neutron profiles were measured for TFTR plasmas with time resolution between 5 msec and 50 msec depending upon count rates. The He detectors were used to measure the burnup of 1 MeV tritons in deuterium plasmas, the transport of tritium in trace tritium experiments, and the residual tritium levels in plasmas following 50:50 DT experiments.

  11. Absolute Gravimetry in Fennoscandia

    DEFF Research Database (Denmark)

    Pettersen, B. R; TImmen, L.; Gitlein, O.

    motions) has its major axis in the direction of southwest to northeast and covers a distance of about 2000 km. Absolute gravimetry was made in Finland and Norway in 1976 with a rise-and fall instrument. A decade later the number of gravity stations was expanded by JILAg-5, in Finland from 1988, in Norway...

  12. The Depsipeptide Romidepsin Reverses HIV-1 Latency In Vivo.

    Directory of Open Access Journals (Sweden)

    Ole S Søgaard

    2015-09-01

    Full Text Available Pharmacologically-induced activation of replication competent proviruses from latency in the presence of antiretroviral treatment (ART has been proposed as a step towards curing HIV-1 infection. However, until now, approaches to reverse HIV-1 latency in humans have yielded mixed results. Here, we report a proof-of-concept phase Ib/IIa trial where 6 aviremic HIV-1 infected adults received intravenous 5 mg/m2 romidepsin (Celgene once weekly for 3 weeks while maintaining ART. Lymphocyte histone H3 acetylation, a cellular measure of the pharmacodynamic response to romidepsin, increased rapidly (maximum fold range: 3.7–7.7 relative to baseline within the first hours following each romidepsin administration. Concurrently, HIV-1 transcription quantified as copies of cell-associated un-spliced HIV-1 RNA increased significantly from baseline during treatment (range of fold-increase: 2.4–5.0; p = 0.03. Plasma HIV-1 RNA increased from <20 copies/mL at baseline to readily quantifiable levels at multiple post-infusion time-points in 5 of 6 patients (range 46–103 copies/mL following the second infusion, p = 0.04. Importantly, romidepsin did not decrease the number of HIV-specific T cells or inhibit T cell cytokine production. Adverse events (all grade 1–2 were consistent with the known side effects of romidepsin. In conclusion, romidepsin safely induced HIV-1 transcription resulting in plasma HIV-1 RNA that was readily detected with standard commercial assays demonstrating that significant reversal of HIV-1 latency in vivo is possible without blunting T cell-mediated immune responses. These finding have major implications for future trials aiming to eradicate the HIV-1 reservoir.clinicaltrials.gov NTC02092116.

  13. Latency in Distributed Acquisition and Rendering for Telepresence Systems.

    Science.gov (United States)

    Ohl, Stephan; Willert, Malte; Staadt, Oliver

    2015-12-01

    Telepresence systems use 3D techniques to create a more natural human-centered communication over long distances. This work concentrates on the analysis of latency in telepresence systems where acquisition and rendering are distributed. Keeping latency low is important to immerse users in the virtual environment. To better understand latency problems and to identify the source of such latency, we focus on the decomposition of system latency into sub-latencies. We contribute a model of latency and show how it can be used to estimate latencies in a complex telepresence dataflow network. To compare the estimates with real latencies in our prototype, we modify two common latency measurement methods. This presented methodology enables the developer to optimize the design, find implementation issues and gain deeper knowledge about specific sources of latency.

  14. Absolute Neutrino Mass Determination

    CERN Document Server

    Päs, H

    2001-01-01

    We discuss four approaches to the determination of absolute neutrino mass. These are the measurement of the zero-neutrino double beta decay rate, of the tritium decay end-point spectrum, of the cosmic ray spectrum above the GZK cutoff, and the cosmological measurement of the power spectrum governing the CMB and large scale structure. The first two approaches are sensitive to the mass eigenstates coupling to the electron neutrino, whereas the latter two are sensitive to the heavy component of the cosmic neutrino background. All mass eigenstates are related by the $\\Delta m^2$'s inferred from neutrino oscillation data. Consequently, the potential for absolute mass determination of each of the four approaches is correlated with the other three, in ways that we point out.

  15. Short REM latency in impotence without depression.

    Science.gov (United States)

    Schmidt, H S; Nofzinger, E A

    1988-05-01

    In a retrospective study, the presence of depression was studied in a group of 14 impotent patients who were selected on the basis of the similarity between their electroencephalographic (EEG) sleep patterns and those of patients with endogenous depression. Specifically, the value of rapid eye movement (REM) latency plus age less than 100 was used as a selection criterion. Sleep continuity disturbances, increased REM time, and increased REM% were noted in the short REM latency impotent group. On the basis of MMPI and psychiatric history and interview, only one of these impotent patients showed major depression. The authors conclude that impotent patients with a short REM latency are not, as a group, depressed and that the incidence of depression in impotent men should be determined irrespective of EEG sleep findings.

  16. Reduced-Latency SC Polar Decoder Architectures

    CERN Document Server

    Zhang, Chuan; Parhi, Keshab K

    2011-01-01

    Polar codes have become one of the most favorable capacity achieving error correction codes (ECC) along with their simple encoding method. However, among the very few prior successive cancellation (SC) polar decoder designs, the required long code length makes the decoding latency high. In this paper, conventional decoding algorithm is transformed with look-ahead techniques. This reduces the decoding latency by 50%. With pipelining and parallel processing schemes, a parallel SC polar decoder is proposed. Sub-structure sharing approach is employed to design the merged processing element (PE). Moreover, inspired by the real FFT architecture, this paper presents a novel input generating circuit (ICG) block that can generate additional input signals for merged PEs on-the-fly. Gate-level analysis has demonstrated that the proposed design shows advantages of 50% decoding latency and twice throughput over the conventional one with similar hardware cost.

  17. MicroRNA-155 Reinforces HIV Latency*

    Science.gov (United States)

    Ruelas, Debbie S.; Chan, Jonathan K.; Oh, Eugene; Heidersbach, Amy J.; Hebbeler, Andrew M.; Chavez, Leonard; Verdin, Eric; Rape, Michael; Greene, Warner C.

    2015-01-01

    The presence of a small number of infected but transcriptionally dormant cells currently thwarts a cure for the more than 35 million individuals infected with HIV. Reactivation of these latently infected cells may result in three fates: 1) cell death due to a viral cytopathic effect, 2) cell death due to immune clearance, or 3) a retreat into latency. Uncovering the dynamics of HIV gene expression and silencing in the latent reservoir will be crucial for developing an HIV-1 cure. Here we identify and characterize an intracellular circuit involving TRIM32, an HIV activator, and miR-155, a microRNA that may promote a return to latency in these transiently activated reservoir cells. Notably, we demonstrate that TRIM32, an E3 ubiquitin ligase, promotes reactivation from latency by directly modifying IκBα, leading to a novel mechanism of NF-κB induction not involving IκB kinase activation. PMID:25873391

  18. A Readout Mechanism for Latency Codes

    Science.gov (United States)

    Zohar, Oran; Shamir, Maoz

    2016-01-01

    Response latency has been suggested as a possible source of information in the central nervous system when fast decisions are required. The accuracy of latency codes was studied in the past using a simplified readout algorithm termed the temporal-winner-take-all (tWTA). The tWTA is a competitive readout algorithm in which populations of neurons with a similar decision preference compete, and the algorithm selects according to the preference of the population that reaches the decision threshold first. It has been shown that this algorithm can account for accurate decisions among a small number of alternatives during short biologically relevant time periods. However, one of the major points of criticism of latency codes has been that it is unclear how can such a readout be implemented by the central nervous system. Here we show that the solution to this long standing puzzle may be rather simple. We suggest a mechanism that is based on reciprocal inhibition architecture, similar to that of the conventional winner-take-all, and show that under a wide range of parameters this mechanism is sufficient to implement the tWTA algorithm. This is done by first analyzing a rate toy model, and demonstrating its ability to discriminate short latency differences between its inputs. We then study the sensitivity of this mechanism to fine-tuning of its initial conditions, and show that it is robust to wide range of noise levels in the initial conditions. These results are then generalized to a Hodgkin-Huxley type of neuron model, using numerical simulations. Latency codes have been criticized for requiring a reliable stimulus-onset detection mechanism as a reference for measuring latency. Here we show that this frequent assumption does not hold, and that, an additional onset estimator is not needed to trigger this simple tWTA mechanism.

  19. Long Latency Auditory Evoked Potentials during Meditation.

    Science.gov (United States)

    Telles, Shirley; Deepeshwar, Singh; Naveen, Kalkuni Visweswaraiah; Pailoor, Subramanya

    2015-10-01

    The auditory sensory pathway has been studied in meditators, using midlatency and short latency auditory evoked potentials. The present study evaluated long latency auditory evoked potentials (LLAEPs) during meditation. Sixty male participants, aged between 18 and 31 years (group mean±SD, 20.5±3.8 years), were assessed in 4 mental states based on descriptions in the traditional texts. They were (a) random thinking, (b) nonmeditative focusing, (c) meditative focusing, and (d) meditation. The order of the sessions was randomly assigned. The LLAEP components studied were P1 (40-60 ms), N1 (75-115 ms), P2 (120-180 ms), and N2 (180-280 ms). For each component, the peak amplitude and peak latency were measured from the prestimulus baseline. There was significant decrease in the peak latency of the P2 component during and after meditation (Pmeditation facilitates the processing of information in the auditory association cortex, whereas the number of neurons recruited was smaller in random thinking and non-meditative focused thinking, at the level of the secondary auditory cortex, auditory association cortex and anterior cingulate cortex.

  20. Absolute airborne gravimetry

    Science.gov (United States)

    Baumann, Henri

    This work consists of a feasibility study of a first stage prototype airborne absolute gravimeter system. In contrast to relative systems, which are using spring gravimeters, the measurements acquired by absolute systems are uncorrelated and the instrument is not suffering from problems like instrumental drift, frequency response of the spring and possible variation of the calibration factor. The major problem we had to resolve were to reduce the influence of the non-gravitational accelerations included in the measurements. We studied two different approaches to resolve it: direct mechanical filtering, and post-processing digital compensation. The first part of the work describes in detail the different mechanical passive filters of vibrations, which were studied and tested in the laboratory and later in a small truck in movement. For these tests as well as for the airborne measurements an absolute gravimeter FG5-L from Micro-G Ltd was used together with an Inertial navigation system Litton-200, a vertical accelerometer EpiSensor, and GPS receivers for positioning. These tests showed that only the use of an optical table gives acceptable results. However, it is unable to compensate for the effects of the accelerations of the drag free chamber. The second part describes the strategy of the data processing. It is based on modeling the perturbing accelerations by means of GPS, EpiSensor and INS data. In the third part the airborne experiment is described in detail, from the mounting in the aircraft and data processing to the different problems encountered during the evaluation of the quality and accuracy of the results. In the part of data processing the different steps conducted from the raw apparent gravity data and the trajectories to the estimation of the true gravity are explained. A comparison between the estimated airborne data and those obtained by ground upward continuation at flight altitude allows to state that airborne absolute gravimetry is feasible and

  1. Towards Controlling Latency in Wireless Networks

    KAUST Repository

    Bouacida, Nader

    2017-04-24

    Wireless networks are undergoing an unprecedented revolution in the last decade. With the explosion of delay-sensitive applications in the Internet (i.e., online gaming and VoIP), latency becomes a major issue for the development of wireless technology. Taking advantage of the significant decline in memory prices, industrialists equip the network devices with larger buffering capacities to improve the network throughput by limiting packets drops. Over-buffering results in increasing the time that packets spend in the queues and, thus, introducing more latency in networks. This phenomenon is known as “bufferbloat”. While throughput is the dominant performance metric, latency also has a huge impact on user experience not only for real-time applications but also for common applications like web browsing, which is sensitive to latencies in order of hundreds of milliseconds. Concerns have arisen about designing sophisticated queue management schemes to mitigate the effects of such phenomenon. My thesis research aims to solve bufferbloat problem in both traditional half-duplex and cutting-edge full-duplex wireless systems by reducing delay while maximizing wireless links utilization and fairness. Our work shed lights on buffer management algorithms behavior in wireless networks and their ability to reduce latency resulting from excessive queuing delays inside oversized static network buffers without a significant loss in other network metrics. First of all, we address the problem of buffer management in wireless full-duplex networks by using Wireless Queue Management (WQM), which is an active queue management technique for wireless networks. Our solution is based on Relay Full-Duplex MAC (RFD-MAC), an asynchronous media access control protocol designed for relay full-duplexing. Compared to the default case, our solution reduces the end-to-end delay by two orders of magnitude while achieving similar throughput in most of the cases. In the second part of this thesis

  2. Absolutely Indecomposable Modules

    CERN Document Server

    Göbel, Rüdiger

    2007-01-01

    A module is called absolutely indecomposable if it is directly indecomposable in every generic extension of the universe. We want to show the existence of large abelian groups that are absolutely indecomposable. This will follow from a more general result about R-modules over a large class of commutative rings R with endomorphism ring R which remains the same when passing to a generic extension of the universe. It turns out that `large' in this context has the precise meaning, namely being smaller then the first omega-Erdos cardinal defined below. We will first apply result on large rigid trees with a similar property established by Shelah in 1982, and will prove the existence of related ` R_omega-modules' (R-modules with countably many distinguished submodules) and finally pass to R-modules. The passage through R_omega-modules has the great advantage that the proofs become very transparent essentially using a few `linear algebra' arguments accessible also for graduate students. The result gives a new constru...

  3. Absolute polarimetry at RHIC

    CERN Document Server

    Okada, H; Bravar, A; Bunce, G; Dhawan, S; Eyser, K O; Gill, R; Haeberli, W; Huang, H; Jinnouchi, O; Makdisi, Y; Nakagawa, I; Nass, A; Saitô, N; Stephenson, E; Sviridia, D; Wise, T; Wood, J; Zelenski, A

    2007-01-01

    Precise and absolute beam polarization measurements are critical for the RHIC spin physics program. Because all experimental spin-dependent results are normalized by beam polarization, the normalization uncertainty contributes directly to final physics uncertainties. We aimed to perform the beam polarization measurement to an accuracy of $\\Delta P_{beam}/P_{beam} < 5%$. The absolute polarimeter consists of Polarized Atomic Hydrogen Gas Jet Target and left-right pairs of silicon strip detectors and was installed in the RHIC-ring in 2004. This system features \\textit{proton-proton} elastic scattering in the Coulomb nuclear interference (CNI) region. Precise measurements of the analyzing power $A_N$ of this process has allowed us to achieve $\\Delta P_{beam}/P_{beam} =4.2%$ in 2005 for the first long spin-physics run. In this report, we describe the entire set up and performance of the system. The procedure of beam polarization measurement and analysis results from 2004-2005 are described. Physics topics of $A...

  4. Latency to CNS oxygen toxicity in rats as a function of PCO(2) and PO(2).

    Science.gov (United States)

    Arieli, R; Ertracht, O

    1999-01-01

    Central nervous system (CNS) oxygen toxicity can occur as convulsions and loss of consciousness, without any premonitory symptoms. We have made a quantitative study of the effect of inspired carbon dioxide on sensitivity to oxygen toxicity in the rat. Rats were exposed to four oxygen pressures (PO(2); 456, 507, 608 and 709 kPa) and an inspired partial pressure of carbon dioxide (PCO(2)) in the range 0-12 kPa until the appearance of the electroencephalograph first electrical discharge (FED) that precedes the clinical convulsions. Exposures were conducted at a thermoneutral temperature of 27 degrees C. Latency to the FED decreased linearly with the increase in PCO(2) at all four PO(2) values studied. This decrease, which is probably related to the cerebral vasodilatory effect of carbon dioxide, reached a minimal value that remained constant on further elevation of PCO(2). The slopes (absolute value) and intercepts of latency to the FED as a function of carbon dioxide decreased with the increase in PO(2). This log-linear relationship made possible the derivation of equations that describe latency to the FED as a function of both PO(2) and PCO(2) in the PCO(2) - dependent range: Latency (min) = e((5.19-0.0040)(P)(O(2)))-e((2.77-0.0034)(P)(O(2))) x PCO(2) (kPa), and in the PCO(2)-independent range: Latency(min) = e((2.44-0. 0009)(P)(O(2))). A PCO(2) as low as 1 kPa significantly reduced the latency to the FED. It is suggested that in closed-circuit oxygen diving, any accumulation of carbon dioxide should be avoided in order to minimize the risk of CNS oxygen toxicity.

  5. Absolute Gravimetry in Fennoscandia

    DEFF Research Database (Denmark)

    Pettersen, B. R; TImmen, L.; Gitlein, O.

    The Fennoscandian postglacial uplift has been mapped geometrically using precise levelling, tide gauges, and networks of permanent GPS stations. The results identify major uplift rates at sites located around the northern part of the Gulf of Bothnia. The vertical motions decay in all directions...... motions) has its major axis in the direction of southwest to northeast and covers a distance of about 2000 km. Absolute gravimetry was made in Finland and Norway in 1976 with a rise-and fall instrument. A decade later the number of gravity stations was expanded by JILAg-5, in Finland from 1988, in Norway...... from 1991, and in Sweden from 1992. FG5 was introduced in these three countries in 1993 (7 stations) and continued with an extended campaign in 1995 (12 stations). In 2003 a project was initiated by IfE, Hannover to collect observations simultaneously with GRACE on an annual cycle. New instruments were...

  6. Optical tweezers absolute calibration

    CERN Document Server

    Dutra, R S; Neto, P A Maia; Nussenzveig, H M

    2014-01-01

    Optical tweezers are highly versatile laser traps for neutral microparticles, with fundamental applications in physics and in single molecule cell biology. Force measurements are performed by converting the stiffness response to displacement of trapped transparent microspheres, employed as force transducers. Usually, calibration is indirect, by comparison with fluid drag forces. This can lead to discrepancies by sizable factors. Progress achieved in a program aiming at absolute calibration, conducted over the past fifteen years, is briefly reviewed. Here we overcome its last major obstacle, a theoretical overestimation of the peak stiffness, within the most employed range for applications, and we perform experimental validation. The discrepancy is traced to the effect of primary aberrations of the optical system, which are now included in the theory. All required experimental parameters are readily accessible. Astigmatism, the dominant effect, is measured by analyzing reflected images of the focused laser spo...

  7. Absolute multilateration between spheres

    Science.gov (United States)

    Muelaner, Jody; Wadsworth, William; Azini, Maria; Mullineux, Glen; Hughes, Ben; Reichold, Armin

    2017-04-01

    Environmental effects typically limit the accuracy of large scale coordinate measurements in applications such as aircraft production and particle accelerator alignment. This paper presents an initial design for a novel measurement technique with analysis and simulation showing that that it could overcome the environmental limitations to provide a step change in large scale coordinate measurement accuracy. Referred to as absolute multilateration between spheres (AMS), it involves using absolute distance interferometry to directly measure the distances between pairs of plain steel spheres. A large portion of each sphere remains accessible as a reference datum, while the laser path can be shielded from environmental disturbances. As a single scale bar this can provide accurate scale information to be used for instrument verification or network measurement scaling. Since spheres can be simultaneously measured from multiple directions, it also allows highly accurate multilateration-based coordinate measurements to act as a large scale datum structure for localized measurements, or to be integrated within assembly tooling, coordinate measurement machines or robotic machinery. Analysis and simulation show that AMS can be self-aligned to achieve a theoretical combined standard uncertainty for the independent uncertainties of an individual 1 m scale bar of approximately 0.49 µm. It is also shown that combined with a 1 µm m‑1 standard uncertainty in the central reference system this could result in coordinate standard uncertainty magnitudes of 42 µm over a slender 1 m by 20 m network. This would be a sufficient step change in accuracy to enable next generation aerospace structures with natural laminar flow and part-to-part interchangeability.

  8. Therapeutics for HIV-1 reactivation from latency.

    Science.gov (United States)

    Sgarbanti, Marco; Battistini, Angela

    2013-08-01

    Intensive combined antiretroviral therapy successfully suppresses HIV-1 replication and AIDS disease progression making infection manageable, but it is unable to eradicate the virus that persists in long-lived, drug-insensitive and immune system-insensitive reservoirs thus asking for life-long treatments with problems of compliance, resistance, toxicity and cost. These limitations and recent insights into latency mechanisms have fueled a renewed effort in finding a cure for HIV-1 infection. Proposed eradication strategies involve reactivation of the latent reservoir upon induction of viral transcription followed by the elimination of reactivated virus-producing cells by viral cytopathic effect or host immune response. Several molecules identified by mechanism-directed approaches or in large-scale screenings have been proposed as latency reversing agents. Some of them have already entered clinical testing in humans but with mixed or unsatisfactory results.

  9. Arbitration in crossbar interconnect for low latency

    Energy Technology Data Exchange (ETDEWEB)

    Ohmacht, Martin; Sugavanam, Krishnan

    2013-02-05

    A system and method and computer program product for reducing the latency of signals communicated through a crossbar switch, the method including using at slave arbitration logic devices associated with Slave devices for which access is requested from one or more Master devices, two or more priority vector signals cycled among their use every clock cycle for selecting one of the requesting Master devices and updates the respective priority vector signal used every clock cycle. Similarly, each Master for which access is requested from one or more Slave devices, can have two or more priority vectors and can cycle among their use every clock cycle to further reduce latency and increase throughput performance via the crossbar.

  10. Epigenetic Control of Cytomegalovirus Latency and Reactivation

    Directory of Open Access Journals (Sweden)

    Mary Hummel

    2013-05-01

    Full Text Available Cytomegalovirus (CMV gene expression is repressed in latency due to heterochromatinization of viral genomes. In murine CMV (MCMV latently infected mice, viral genomes are bound to histones with heterochromatic modifications, to enzymes that mediate these modifications, and to adaptor proteins that may recruit co-repressor complexes. Kinetic analyses of repressor binding show that these repressors are recruited at the earliest time of infection, suggesting that latency may be the default state. Kidney transplantation leads to epigenetic reprogramming of latent viral chromatin and reactivation of immediate early gene expression. Inflammatory signaling pathways, which activate transcription factors that regulate the major immediate early promoter (MIEP, likely mediate the switch in viral chromatin.

  11. Arbitration in crossbar interconnect for low latency

    Science.gov (United States)

    Ohmacht, Martin; Sugavanam, Krishnan

    2013-02-05

    A system and method and computer program product for reducing the latency of signals communicated through a crossbar switch, the method including using at slave arbitration logic devices associated with Slave devices for which access is requested from one or more Master devices, two or more priority vector signals cycled among their use every clock cycle for selecting one of the requesting Master devices and updates the respective priority vector signal used every clock cycle. Similarly, each Master for which access is requested from one or more Slave devices, can have two or more priority vectors and can cycle among their use every clock cycle to further reduce latency and increase throughput performance via the crossbar.

  12. Response rate, latency, and resistance to change

    Science.gov (United States)

    Fath, Stephen J.; Fields, Lanny; Malott, M. Kay; Grossett, Deborah

    1983-01-01

    Pigeons were trained on a multiple variable-interval/variable-interval schedule with pacing contingencies that generated high response rates in one component and low response rates in the other. Timeout periods separated the schedule components. During resistance-to-change tests, response-independent food was presented during the timeout periods, and the duration of that food presentation was varied among test sessions. Response rates in the schedule components decreased and latencies to the first response increased as a function of the duration of food presentations during the timeout. Both dependent measures changed about the same amount relative to their own baseline levels. The conclusions are that baseline response rates controlled by pacing contingencies are equally resistant to change, given equal reinforcement densities, and latency is a sensitive measure of resistance to change. PMID:16812319

  13. Detecting Intermediary Hosts by TCP Latency Measurements

    Science.gov (United States)

    Singh, Gurvinder; Eian, Martin; Willassen, Svein Y.; Mjølsnes, Stig Fr.

    Use of intermediary hosts as stepping stones to conceal tracks is common in Internet misuse. It is therefore desirable to find a method to detect whether the originating party is using an intermediary host. Such a detection technique would allow the activation of a number of countermeasures that would neutralize the effects of misuse, and make it easier to trace a perpetrator. This work explores a new approach in determining if a host communicating via TCP is the data originator or if it is acting as a mere TCP proxy. The approach is based on measuring the inter packet arrival time at the receiving end of the connection only, and correlating the observed results with the network latency between the receiver and the proxy. The results presented here indicate that determining the use of a proxy host is possible, if the network latency between the originator and proxy is larger than the network latency between the proxy and the receiver. We show that this technique has potential to be used to detect connections were data is sent through a TCP proxy, such as remote login through TCP proxies, or rejecting spam sent through a bot network.

  14. Glomerular latency coding in artificial olfaction

    Directory of Open Access Journals (Sweden)

    Jaber eAl Yamani

    2012-01-01

    Full Text Available Sensory perception results from the way sensory information is subsequently transformed in the brain. Olfaction is a typical example in which odor representations undergo considerable changes as they pass from olfactory receptor neurons (ORNs to second-order neurons. First, many ORNs expressing the same receptor protein yet presenting heterogeneous dose-response properties converge onto individually identifiable glomeruli. Second, onset latency of glomerular activation is believed to play a role in encoding odor quality and quantity in the context of fast information processing. Taking inspiration from the olfactory pathway, we designed a simple yet robust glomerular latency coding scheme for processing gas sensor data. The proposed bio-inspired approach was evaluated using an in-house Sn02 sensor array. Glomerular convergence was achieved by noting the possible analogy between receptor protein expressed in ORNs and metal catalyst used across the fabricated gas sensor array. Ion implantation was another technique used to account both for sensor heterogeneity and enhanced sensitivity. The response of the gas sensor array was mapped into glomerular latency patterns, whose rank order is concentration-invariant. Gas recognition was achieved by simply looking for a match within a library of spatio-temporal spike fingerprints. Because of its simplicity, this approach enables the integration of sensing and processing onto a single-chip.

  15. HIV-1 Latency in Monocytes/Macrophages

    Directory of Open Access Journals (Sweden)

    Amit Kumar

    2014-04-01

    Full Text Available Human immunodeficiency virus type 1 (HIV-1 targets CD4+ T cells and cells of the monocyte/macrophage lineage. HIV pathogenesis is characterized by the depletion of T lymphocytes and by the presence of a population of cells in which latency has been established called the HIV-1 reservoir. Highly active antiretroviral therapy (HAART has significantly improved the life of HIV-1 infected patients. However, complete eradication of HIV-1 from infected individuals is not possible without targeting latent sources of infection. HIV-1 establishes latent infection in resting CD4+ T cells and findings indicate that latency can also be established in the cells of monocyte/macrophage lineage. Monocyte/macrophage lineage includes among others, monocytes, macrophages and brain resident macrophages. These cells are relatively more resistant to apoptosis induced by HIV-1, thus are important stable hideouts of the virus. Much effort has been made in the direction of eliminating HIV-1 resting CD4+ T-cell reservoirs. However, it is impossible to achieve a cure for HIV-1 without considering these neglected latent reservoirs, the cells of monocyte/macrophage lineage. In this review we will describe our current understanding of the mechanism of latency in monocyte/macrophage lineage and how such cells can be specifically eliminated from the infected host.

  16. MicroRNA-155 Reinforces HIV Latency.

    Science.gov (United States)

    Ruelas, Debbie S; Chan, Jonathan K; Oh, Eugene; Heidersbach, Amy J; Hebbeler, Andrew M; Chavez, Leonard; Verdin, Eric; Rape, Michael; Greene, Warner C

    2015-05-29

    The presence of a small number of infected but transcriptionally dormant cells currently thwarts a cure for the more than 35 million individuals infected with HIV. Reactivation of these latently infected cells may result in three fates: 1) cell death due to a viral cytopathic effect, 2) cell death due to immune clearance, or 3) a retreat into latency. Uncovering the dynamics of HIV gene expression and silencing in the latent reservoir will be crucial for developing an HIV-1 cure. Here we identify and characterize an intracellular circuit involving TRIM32, an HIV activator, and miR-155, a microRNA that may promote a return to latency in these transiently activated reservoir cells. Notably, we demonstrate that TRIM32, an E3 ubiquitin ligase, promotes reactivation from latency by directly modifying IκBα, leading to a novel mechanism of NF-κB induction not involving IκB kinase activation. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  17. Molecular control of HIV-1 postintegration latency: implications for the development of new therapeutic strategies

    Directory of Open Access Journals (Sweden)

    Van Lint Carine

    2009-12-01

    Full Text Available Abstract The persistence of HIV-1 latent reservoirs represents a major barrier to virus eradication in infected patients under HAART since interruption of the treatment inevitably leads to a rebound of plasma viremia. Latency establishes early after infection notably (but not only in resting memory CD4+ T cells and involves numerous host and viral trans-acting proteins, as well as processes such as transcriptional interference, RNA silencing, epigenetic modifications and chromatin organization. In order to eliminate latent reservoirs, new strategies are envisaged and consist of reactivating HIV-1 transcription in latently-infected cells, while maintaining HAART in order to prevent de novo infection. The difficulty lies in the fact that a single residual latently-infected cell can in theory rekindle the infection. Here, we review our current understanding of the molecular mechanisms involved in the establishment and maintenance of HIV-1 latency and in the transcriptional reactivation from latency. We highlight the potential of new therapeutic strategies based on this understanding of latency. Combinations of various compounds used simultaneously allow for the targeting of transcriptional repression at multiple levels and can facilitate the escape from latency and the clearance of viral reservoirs. We describe the current advantages and limitations of immune T-cell activators, inducers of the NF-κB signaling pathway, and inhibitors of deacetylases and histone- and DNA- methyltransferases, used alone or in combinations. While a solution will not be achieved by tomorrow, the battle against HIV-1 latent reservoirs is well- underway.

  18. Data latency and the user community

    Science.gov (United States)

    Escobar, V. M.; Brown, M. E.; Carroll, M.

    2013-12-01

    The community using NASA Earth science observations in applications has grown significantly, with increasing sophistication to serve national interests. The National Research Council's Earth Science Decadal Survey report stated that the planning for applied and operational considerations in the missions should accompany the acquisition of new knowledge about Earth (NRC, 2007). This directive has made product applications at NASA an integral part of converting the data collected into actionable knowledge that can be used to inform policy. However, successfully bridging scientific research with operational decision making in different application areas requires looking into user data requirements and operational needs. This study was conducted to determine how users are incorporating NASA data into applications and operational processes. The approach included a review of published materials, direct interviews with mission representatives, and an online professional review, which was distributed to over 6000 individuals. We provide a complete description of the findings with definitions and explanations of what goes into measuring latency as well as how users and applications utilize NASA data products. We identified 3 classes of users: operational (need data in 3 hours or less), near real time (need data within a day of acquisition), and scientific users (need highest quality data, time independent). We also determined that most users with applications are interested in specific types of products that may come from multiple missions. These users will take the observations when they are available, however the observations may have additional applications value if they are available either by a certain time of day or within a period of time after acquisition. NASA has supported the need for access to low latency data on an ad-hoc basis and more substantively in stand-alone systems such as the MODIS Rapid Response system and more recently with LANCE. The increased level

  19. Genetic variants in RBFOX3 are associated with sleep latency

    NARCIS (Netherlands)

    Amin, Najaf; Allebrandt, Karla V.; van der Spek, Ashley; Mueller-Myhsok, Bertram; Hek, Karin; Teder-Laving, Maris; Hayward, Caroline; Esko, Tonu; van Mill, Josine G.; Mbarek, Hamdi; Watson, Nathaniel F.; Melville, Scott A.; Del Greco, Fabiola M.; Byrne, Enda M.; Oole, Edwin; Kolcic, Ivana; Chen, Ting-hsu; Evans, Daniel S.; Coresh, Josef; Vogelzangs, Nicole; Karjalainen, Juha; Willemsen, Gonneke; Gharib, Sina A.; Zgaga, Lina; Mihailov, Evelin; Stone, Katie L.; Campbell, Harry; Brouwer, Rutger Ww; Demirkan, Ayse; Isaacs, Aaron; Dogas, Zoran; Marciante, Kristin D.; Campbell, Susan; Borovecki, Fran; Luik, Annemarie I.; Li, Man; Hottenga, Jouke Jan; Huffman, Jennifer E.; van den Hout, Mirjam C. G. N.; Cummings, Steven R.; Aulchenko, Yuru S.; Gehrman, Philip R.; Uitterlinden, Andre G.; Wichmann, Heinz-Erich; Muller-Nurasyid, Martina; Fehrmann, Rudolf S. N.; Montgomery, Grant W.; Hofman, Albert; Kao, Wen Hong Linda; Oostra, Ben A.; Wright, Alan F.; Vink, Jacqueline M.; Wilson, James F.; Pramstaller, Peter P.; Hicks, Andrew A.; Polasek, Ozren; Punjabi, Naresh M.; Redline, Susan; Psaty, Bruce M.; Heath, Andrew C.; Merrow, Martha; Tranah, Gregory J.; Gottlieb, Daniel J.; Boomsma, Dorret I.; Martin, Nicholas G.; Rudan, Igor; Tiemeier, Henning; van IJcken, Wilfred F. J.; Penninx, Brenda W.; Metspalu, Andres; Meitinger, Thomas; Franke, Lude; Roenneberg, Till; van Duijn, Cornelia M.

    2016-01-01

    Time to fall asleep (sleep latency) is a major determinant of sleep quality. Chronic, long sleep latency is a major characteristic of sleep-onset insomnia and/or delayed sleep phase syndrome. In this study we aimed to discover common polymorphisms that contribute to the genetics of sleep latency. We

  20. Estimating Absolute Site Effects

    Energy Technology Data Exchange (ETDEWEB)

    Malagnini, L; Mayeda, K M; Akinci, A; Bragato, P L

    2004-07-15

    The authors use previously determined direct-wave attenuation functions as well as stable, coda-derived source excitation spectra to isolate the absolute S-wave site effect for the horizontal and vertical components of weak ground motion. They used selected stations in the seismic network of the eastern Alps, and find the following: (1) all ''hard rock'' sites exhibited deamplification phenomena due to absorption at frequencies ranging between 0.5 and 12 Hz (the available bandwidth), on both the horizontal and vertical components; (2) ''hard rock'' site transfer functions showed large variability at high-frequency; (3) vertical-motion site transfer functions show strong frequency-dependence, and (4) H/V spectral ratios do not reproduce the characteristics of the true horizontal site transfer functions; (5) traditional, relative site terms obtained by using reference ''rock sites'' can be misleading in inferring the behaviors of true site transfer functions, since most rock sites have non-flat responses due to shallow heterogeneities resulting from varying degrees of weathering. They also use their stable source spectra to estimate total radiated seismic energy and compare against previous results. they find that the earthquakes in this region exhibit non-constant dynamic stress drop scaling which gives further support for a fundamental difference in rupture dynamics between small and large earthquakes. To correct the vertical and horizontal S-wave spectra for attenuation, they used detailed regional attenuation functions derived by Malagnini et al. (2002) who determined frequency-dependent geometrical spreading and Q for the region. These corrections account for the gross path effects (i.e., all distance-dependent effects), although the source and site effects are still present in the distance-corrected spectra. The main goal of this study is to isolate the absolute site effect (as a function of frequency

  1. Method to obtain absolute impurity density profiles combining charge exchange and beam emission spectroscopy without absolute intensity calibrationa)

    Science.gov (United States)

    Kappatou, A.; Jaspers, R. J. E.; Delabie, E.; Marchuk, O.; Biel, W.; Jakobs, M. A.

    2012-10-01

    Investigation of impurity transport properties in tokamak plasmas is essential and a diagnostic that can provide information on the impurity content is required. Combining charge exchange recombination spectroscopy (CXRS) and beam emission spectroscopy (BES), absolute radial profiles of impurity densities can be obtained from the CXRS and BES intensities, electron density and CXRS and BES emission rates, without requiring any absolute calibration of the spectra. The technique is demonstrated here with absolute impurity density radial profiles obtained in TEXTOR plasmas, using a high efficiency charge exchange spectrometer with high etendue, that measures the CXRS and BES spectra along the same lines-of-sight, offering an additional advantage for the determination of absolute impurity densities.

  2. Method to obtain absolute impurity density profiles combining charge exchange and beam emission spectroscopy without absolute intensity calibration

    Energy Technology Data Exchange (ETDEWEB)

    Kappatou, A.; Delabie, E. [FOM Institute DIFFER - Dutch Institute for Fundamental Energy Research, Association EURATOM-FOM, 3430 BE Nieuwegein (Netherlands); Jaspers, R. J. E.; Jakobs, M. A. [Science and Technology of Nuclear Fusion, Eindhoven University of Technology, 5600 MB Eindhoven (Netherlands); Marchuk, O.; Biel, W. [Institute for Energy and Climate Research, Forschungszentrum Julich GmbH, Trilateral Euregio Cluster, 52425 Julich (Germany)

    2012-10-15

    Investigation of impurity transport properties in tokamak plasmas is essential and a diagnostic that can provide information on the impurity content is required. Combining charge exchange recombination spectroscopy (CXRS) and beam emission spectroscopy (BES), absolute radial profiles of impurity densities can be obtained from the CXRS and BES intensities, electron density and CXRS and BES emission rates, without requiring any absolute calibration of the spectra. The technique is demonstrated here with absolute impurity density radial profiles obtained in TEXTOR plasmas, using a high efficiency charge exchange spectrometer with high etendue, that measures the CXRS and BES spectra along the same lines-of-sight, offering an additional advantage for the determination of absolute impurity densities.

  3. Enhancements to the multiple sleep latency test

    Directory of Open Access Journals (Sweden)

    Meza-Vargas S

    2016-05-01

    Full Text Available Sonia Meza-Vargas, Eleni Giannouli, Magdy Younes Sleep Disorders Centre, University of Manitoba, Winnipeg, MB, Canada Introduction: The utility of multiple sleep latency tests (MSLTs is limited to determining sleep onset latency (SOL and rapid eye movement sleep latency. The odds ratio product (ORP is a continuous index of sleep depth with values of 0, 1.0, and 2.5 reflecting very deep sleep, light sleep, and full wakefulness, respectively. We determined the time course of sleep depth during MSLT naps expecting that this would enhance the test's clinical utility. Methods: Thirty MSLTs (150 naps were performed for excessive somnolence. Patients indicated whether they slept (yes/no after each nap. SOL was scored by two experienced technologists. Time course of ORP was determined with a commercial system. We determined ORP at SOL (ORPSOL, times ORP decreased <2.0, <1.5, <1.0 and <0.5 during the entire nap duration, and the integral of decrease in ORP over nap duration (ΔORPINT. Results: SOL occurred almost invariably when ORP was between 1.0 and 2.0. Of 47 naps (21 patients with SOL ,5 minutes, ORP decreased <1.0 (light sleep in <5 minutes in only 13 naps (nine patients and <0.5 (deep sleep in only two naps in one patient. The relation between ORPINT and frequency of sleep perception was well defined, allowing determination of a threshold for sleep perception. This threshold ranged widely (5–50 ΔORP*epoch. Conclusion: As currently identified, SOL reflects transition into a highly unstable state between wakefulness and sleep. Reporting the times of attaining different sleep depths may help better identify patients at high risk of vigilance loss. Furthermore, an ORPSOL outside the range 1.0–2.0 can help identify scoring errors. Keywords: odds ratio product, sleep perception, idiopathic hypersomnia

  4. Notes on absolute Hodge classes

    CERN Document Server

    Charles, François

    2011-01-01

    We survey the theory of absolute Hodge classes. The notes include a full proof of Deligne's theorem on absolute Hodge classes on abelian varieties as well as a discussion of other topics, such as the field of definition of Hodge loci and the Kuga-Satake construction.

  5. HIV-1 transcription and latency: an update

    Science.gov (United States)

    2013-01-01

    Combination antiretroviral therapy, despite being potent and life-prolonging, is not curative and does not eradicate HIV-1 infection since interruption of treatment inevitably results in a rapid rebound of viremia. Reactivation of latently infected cells harboring transcriptionally silent but replication-competent proviruses is a potential source of persistent residual viremia in cART-treated patients. Although multiple reservoirs may exist, the persistence of resting CD4+ T cells carrying a latent infection represents a major barrier to eradication. In this review, we will discuss the latest reports on the molecular mechanisms that may regulate HIV-1 latency at the transcriptional level, including transcriptional interference, the role of cellular factors, chromatin organization and epigenetic modifications, the viral Tat trans-activator and its cellular cofactors. Since latency mechanisms may also operate at the post-transcriptional level, we will consider inhibition of nuclear RNA export and inhibition of translation by microRNAs as potential barriers to HIV-1 gene expression. Finally, we will review the therapeutic approaches and clinical studies aimed at achieving either a sterilizing cure or a functional cure of HIV-1 infection, with a special emphasis on the most recent pharmacological strategies to reactivate the latent viruses and decrease the pool of viral reservoirs. PMID:23803414

  6. [Intravaginal ejaculatory latency time: Advances in studies].

    Science.gov (United States)

    Wang, Wan-rong; Xie, Sheng

    2016-02-01

    Although premature ejaculation (PE) is a common type of male sexual dysfunction, to date we lack a unified definition of PE. The multidimensional definition of PE has been accepted by more and more clinicians. Intravaginal ejaculatory latency time (IELT) is one of the three important dimensions (time to ejaculation, inability to control or delay ejaculation, and negative consequences) for defining PE. Rapid ejaculation is one of the core symptoms of PE and IELT is an objective measurement as well as an important tool for the evaluation of PE. This article reviews estimated IELT, stopwatch-measured IELT, the correlation between estimated and stopwatch-measured IELT, and the factors affecting IELT in the general male population, PE patients, and those complaining of PE.

  7. Molecular Understanding of HIV-1 Latency

    Directory of Open Access Journals (Sweden)

    W. Abbas

    2012-01-01

    Full Text Available The introduction of highly active antiretroviral therapy (HAART has been an important breakthrough in the treatment of HIV-1 infection and has also a powerful tool to upset the equilibrium of viral production and HIV-1 pathogenesis. Despite the advent of potent combinations of this therapy, the long-lived HIV-1 reservoirs like cells from monocyte-macrophage lineage and resting memory CD4+ T cells which are established early during primary infection constitute a major obstacle to virus eradication. Further HAART interruption leads to immediate rebound viremia from latent reservoirs. This paper focuses on the essentials of the molecular mechanisms for the establishment of HIV-1 latency with special concern to present and future possible treatment strategies to completely purge and target viral persistence in the reservoirs.

  8. Speeding up parallel GROMACS on high-latency networks.

    Science.gov (United States)

    Kutzner, Carsten; van der Spoel, David; Fechner, Martin; Lindahl, Erik; Schmitt, Udo W; de Groot, Bert L; Grubmüller, Helmut

    2007-09-01

    We investigate the parallel scaling of the GROMACS molecular dynamics code on Ethernet Beowulf clusters and what prerequisites are necessary for decent scaling even on such clusters with only limited bandwidth and high latency. GROMACS 3.3 scales well on supercomputers like the IBM p690 (Regatta) and on Linux clusters with a special interconnect like Myrinet or Infiniband. Because of the high single-node performance of GROMACS, however, on the widely used Ethernet switched clusters, the scaling typically breaks down when more than two computer nodes are involved, limiting the absolute speedup that can be gained to about 3 relative to a single-CPU run. With the LAM MPI implementation, the main scaling bottleneck is here identified to be the all-to-all communication which is required every time step. During such an all-to-all communication step, a huge amount of messages floods the network, and as a result many TCP packets are lost. We show that Ethernet flow control prevents network congestion and leads to substantial scaling improvements. For 16 CPUs, e.g., a speedup of 11 has been achieved. However, for more nodes this mechanism also fails. Having optimized an all-to-all routine, which sends the data in an ordered fashion, we show that it is possible to completely prevent packet loss for any number of multi-CPU nodes. Thus, the GROMACS scaling dramatically improves, even for switches that lack flow control. In addition, for the common HP ProCurve 2848 switch we find that for optimum all-to-all performance it is essential how the nodes are connected to the switch's ports. This is also demonstrated for the example of the Car-Parinello MD code.

  9. Absoluteness or relativity of morality

    Directory of Open Access Journals (Sweden)

    I. A. Kadievskaya

    2014-02-01

    Full Text Available Article is dedicated to the case study of absoluteness or relativity of morals. The questions are in a new way comprehended: Can exist absolute morals? Is how its content? Is necessary it for humanity? Is moral personality absolute value? Does justify the purpose of means? It is substantiated, that reflecting about the problem of absoluteness or relativity of morals, one ought not to be abstracted from the religion ­ billions of people find in it the basis of their morals. Accumulated ethical experience is infinitely rich and diverse in humanity: it includes and the proclaimed prophets godly revelations, and the brilliant enlightenment of secular philosophers. Are analyzed such concepts, as morals, absolute morals, relativity, moral rigorizm, moral personality, formal ethics. The specific character of the moral relativity, which proclaims historicity and changeability of standards and standards of human behavior, is established. Moral rigorizm is understood as the principle, according to which the man must act only from the considerations of moral debt, whereas all other external motivations (interest, happiness, friendship, etc have no moral value. Is shown the priority significance of the nerigoristskoy formal ethics, in which strong idealizations and abstractions of the ethics of moral rigorizma are substituted by the weaker ­ more realistic and more humane. In the nerigoristskoy formal ethics, as in the life, moral estimations completely can be and in the overwhelming majority of the cases are relative.

  10. Latency represents sound frequency in mouse IC

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Frequency is one of the fundamental parameters of sound.The frequency of an acoustic stimulus can be represented by a neural response such as spike rate,and/or first spike latency(FSL)of a given neuron.The spike rates/frequency function of most neurons changes with different acoustic ampli-tudes,whereas FSL/frequency function is highly stable.This implies that FSL might represent the fre-quency of a sound stimulus more efficiently than spike rate.This study involved representations of acoustic frequency by spike rate and FSL of central inferior colliculus(IC)neurons responding to free-field pure-tone stimuli.We found that the FSLs of neurons responding to characteristic frequency(CF)of sound stimulus were usually the shortest,regardless of sound intensity,and that spike rates of most neurons showed a variety of function according to sound frequency,especially at high intensities.These results strongly suggest that FSL of auditory IC neurons can represent sound frequency more precisely than spike rate.

  11. Latency represents sound frequency in mouse IC

    Institute of Scientific and Technical Information of China (English)

    QIU Qiang; TANG Jie; YU ZuLin; ZHANG Juan; ZHOU YingJie; XIAO ZhongJu; SHEN JunXian

    2007-01-01

    Frequency is one of the fundamental parameters of sound. The frequency of an acoustic stimulus can be represented by a neural response such as spike rate, and/or first spike latency (FSL) of a given neuron. The spike rates/frequency function of most neurons changes with different acoustic amplitudes, whereas FSL/frequency function is highly stable. This implies that FSL might represent the frequency of a sound stimulus more efficiently than spike rate. This study involved representations of acoustic frequency by spike rate and FSL of central inferior colliculus (IC) neurons responding to free-field pure-tone stimuli. We found that the FSLs of neurons responding to characteristic frequency (CF) of sound stimulus were usually the shortest, regardless of sound intensity, and that spike rates of most neurons showed a variety of function according to sound frequency, especially at high intensities.These results strongly suggest that FSL of auditory IC neurons can represent sound frequency more precisely than spike rate.

  12. Human hair genealogies and stem cell latency

    Directory of Open Access Journals (Sweden)

    Tavaré Simon

    2006-02-01

    Full Text Available Abstract Background Stem cells divide to reproduce themselves and produce differentiated progeny. A fundamental problem in human biology has been the inability to measure how often stem cells divide. Although it is impossible to observe every division directly, one method for counting divisions is to count replication errors; the greater the number of divisions, the greater the numbers of errors. Stem cells with more divisions should produce progeny with more replication errors. Methods To test this approach, epigenetic errors (methylation in CpG-rich molecular clocks were measured from human hairs. Hairs exhibit growth and replacement cycles and "new" hairs physically reappear even on "old" heads. Errors may accumulate in long-lived stem cells, or in their differentiated progeny that are eventually shed. Results Average hair errors increased until two years of age, and then were constant despite decades of replacement, consistent with new hairs arising from infrequently dividing bulge stem cells. Errors were significantly more frequent in longer hairs, consistent with long-lived but eventually shed mitotic follicle cells. Conclusion Constant average hair methylation regardless of age contrasts with the age-related methylation observed in human intestine, suggesting that error accumulation and therefore stem cell latency differs among tissues. Epigenetic molecular clocks imply similar mitotic ages for hairs on young and old human heads, consistent with a restart with each new hair, and with genealogies surreptitiously written within somatic cell genomes.

  13. Low latency memory access and synchronization

    Energy Technology Data Exchange (ETDEWEB)

    Blumrich, Matthias A. (Ridgefield, CT); Chen, Dong (Croton On Hudson, NY); Coteus, Paul W. (Yorktown Heights, NY); Gara, Alan G. (Mount Kisco, NY); Giampapa, Mark E. (Irvington, NY); Heidelberger, Philip (Cortlandt Manor, NY); Hoenicke, Dirk (Ossining, NY); Ohmacht, Martin (Brewster, NY); Steinmacher-Burow, Burkhard D. (Mount Kisco, NY); Takken, Todd E. (Mount Kisco, NY), Vranas; Pavlos M. (Bedford Hills, NY)

    2010-10-19

    A low latency memory system access is provided in association with a weakly-ordered multiprocessor system. Bach processor in the multiprocessor shares resources, and each shared resource has an associated lock within a locking device that provides support for synchronization between the multiple processors in the multiprocessor and the orderly sharing of the resources. A processor only has permission to access a resource when it owns the lock associated with that resource, and an attempt by a processor to own a lock requires only a single load operation, rather than a traditional atomic load followed by store, such that the processor only performs a read operation and the hardware locking device performs a subsequent write operation rather than the processor. A simple prefetching for non-contiguous data structures is also disclosed. A memory line is redefined so that in addition to the normal physical memory data, every line includes a pointer that is large enough to point to any other line in the memory, wherein the pointers to determine which memory line to prefetch rather than some other predictive algorithm. This enables hardware to effectively prefetch memory access patterns that are non-contiguous, but repetitive.

  14. Low latency memory access and synchronization

    Science.gov (United States)

    Blumrich, Matthias A.; Chen, Dong; Coteus, Paul W.; Gara, Alan G.; Giampapa, Mark E.; Heidelberger, Philip; Hoenicke, Dirk; Ohmacht, Martin; Steinmacher-Burow, Burkhard D.; Takken, Todd E. , Vranas; Pavlos M.

    2010-10-19

    A low latency memory system access is provided in association with a weakly-ordered multiprocessor system. Bach processor in the multiprocessor shares resources, and each shared resource has an associated lock within a locking device that provides support for synchronization between the multiple processors in the multiprocessor and the orderly sharing of the resources. A processor only has permission to access a resource when it owns the lock associated with that resource, and an attempt by a processor to own a lock requires only a single load operation, rather than a traditional atomic load followed by store, such that the processor only performs a read operation and the hardware locking device performs a subsequent write operation rather than the processor. A simple prefetching for non-contiguous data structures is also disclosed. A memory line is redefined so that in addition to the normal physical memory data, every line includes a pointer that is large enough to point to any other line in the memory, wherein the pointers to determine which memory line to prefetch rather than some other predictive algorithm. This enables hardware to effectively prefetch memory access patterns that are non-contiguous, but repetitive.

  15. Genetic variants in RBFOX3 are associated with sleep latency

    NARCIS (Netherlands)

    N. Amin (Najaf); K.V. Allebrandt; A. van der Spek (Ashley); B. Müller-Myhsok (B.); K. Hek (Karin); M. Teder-Laving (Maris); C. Hayward (Caroline); T. Esko (Tõnu); J. van Mill; H. Mbarek; N.F. Watson (Nathaniel F); S.A. Melville (Scott); F.M. Del Greco (Fabiola); E.M. Byrne (Enda); E. Oole (Edwin); I. Kolcic (Ivana); T.H. Chen; D.S. Evans (Daniel); J. Coresh (Josef); N. Vogelzangs (Nicole); J. Karjalainen (Juha); G.A.H.M. Willemsen (Gonneke); S.A. Gharib (Sina); L. Zgaga (Lina); E. Mihailov (Evelin); K.L. Stone (Katie L); H. Campbell (Harry); R.W.W. Brouwer (Rutger); A. Demirkan (Ayşe); A.J. Isaacs (Aaron); Z. Dogas; K. Marciante (Kristin); S. Campbell (Susan); F. Borovecki (Fran); A.I. Luik (Annemarie I); M. Li (Man); J.J. Hottenga (Jouke Jan); J.E. Huffman (Jennifer); M.C.G.N. van den hout (Mirjam); S.R. Cummings (Steven R.); Y.S. Aulchenko (Yurii); P.R. Gehrman (Philip); A.G. Uitterlinden (André); H.E. Wichmann (Heinz Erich); M. Müller-Nurasyid (Martina); R.S.N. Fehrmann (Rudolf); G.W. Montgomery (Grant); A. Hofman (Albert); W.H.L. Kao (Wen Hong Linda); B.A. Oostra (Ben); A. Wright (Alan); J.M. Vink (Jacqueline); J.F. Wilson (James F); P.P. Pramstaller (Peter Paul); A.A. Hicks (Andrew); O. Polasek (Ozren); N.M. Punjabi (Naresh); S. Redline (Susan); B.M. Psaty (Bruce); A.C. Heath (Andrew C.); M. Merrow; G.J. Tranah (Gregory); D.J. Gottlieb (Daniel J); D.I. Boomsma (Dorret); N.G. Martin (Nicholas); I. Rudan (Igor); H.W. Tiemeier (Henning); W.F.J. van IJcken (Wilfred); B.W.J.H. Penninx; A. Metspalu (Andres); T. Meitinger (Thomas); L. Franke (Lude); T. Roenneberg; C.M. van Duijn (Cock)

    2016-01-01

    textabstractTime to fall asleep (sleep latency) is a major determinant of sleep quality. Chronic, long sleep latency is a major characteristic of sleep-onset insomnia and/or delayed sleep phase syndrome. In this study we aimed to discover common polymorphisms that contribute to the genetics of sleep

  16. Inhibition of superinfection and the evolution of viral latency

    NARCIS (Netherlands)

    Berngruber, Thomas W.; Weissing, Franz J.; Gandon, Sylvain

    2010-01-01

    Latent viruses generally defend their host cell against superinfection by nonlatent virulent mutants that could destroy the host cell. Superinfection inhibition thus seems to be a prerequisite for the maintenance of viral latency. Yet viral latency can break down when resistance to superinfection in

  17. Database applicaton for absolute spectrophotometry

    Science.gov (United States)

    Bochkov, Valery V.; Shumko, Sergiy

    2002-12-01

    32-bit database application with multidocument interface for Windows has been developed to calculate absolute energy distributions of observed spectra. The original database contains wavelength calibrated observed spectra which had been already passed through apparatus reductions such as flatfielding, background and apparatus noise subtracting. Absolute energy distributions of observed spectra are defined in unique scale by means of registering them simultaneously with artificial intensity standard. Observations of sequence of spectrophotometric standards are used to define absolute energy of the artificial standard. Observations of spectrophotometric standards are used to define optical extinction in selected moments. FFT algorithm implemented in the application allows performing convolution (deconvolution) spectra with user-defined PSF. The object-oriented interface has been created using facilities of C++ libraries. Client/server model with Windows Socket functionality based on TCP/IP protocol is used to develop the application. It supports Dynamic Data Exchange conversation in server mode and uses Microsoft Exchange communication facilities.

  18. Latency and User Performance in Virtual Environments and Augmented Reality

    Science.gov (United States)

    Ellis, Stephen R.

    2009-01-01

    System rendering latency has been recognized by senior researchers, such as Professor Fredrick Brooks of UNC (Turing Award 1999), as a major factor limiting the realism and utility of head-referenced displays systems. Latency has been shown to reduce the user's sense of immersion within a virtual environment, disturb user interaction with virtual objects, and to contribute to motion sickness during some simulation tasks. Latency, however, is not just an issue for external display systems since finite nerve conduction rates and variation in transduction times in the human body's sensors also pose problems for latency management within the nervous system. Some of the phenomena arising from the brain's handling of sensory asynchrony due to latency will be discussed as a prelude to consideration of the effects of latency in interactive displays. The causes and consequences of the erroneous movement that appears in displays due to latency will be illustrated with examples of the user performance impact provided by several experiments. These experiments will review the generality of user sensitivity to latency when users judge either object or environment stability. Hardware and signal processing countermeasures will also be discussed. In particular the tuning of a simple extrapolative predictive filter not using a dynamic movement model will be presented. Results show that it is possible to adjust this filter so that the appearance of some latencies may be hidden without the introduction of perceptual artifacts such as overshoot. Several examples of the effects of user performance will be illustrated by three-dimensional tracking and tracing tasks executed in virtual environments. These experiments demonstrate classic phenomena known from work on manual control and show the need for very responsive systems if they are indented to support precise manipulation. The practical benefits of removing interfering latencies from interactive systems will be emphasized with some

  19. Serial analysis of gene expression predicts structural differences in hippocampus of long attack latency and short attack latency mice

    NARCIS (Netherlands)

    Feldker, DEM; Datson, NA; Veenema, AH; Meulmeester, E; de Kloet, ER; Vreugdenhil, E

    2003-01-01

    The genetically selected long attack latency (LAL) and short attack latency (SAL) mice differ in a wide variety of behavioural traits and display differences in the serotonergic system and the hypothalamus-pituitary-adrenocortical (HPA)-axis. Serial analysis of gene expression (SAGE) was used to gen

  20. Absolute luminosity measurements at LHCb

    CERN Document Server

    Hopchev, Plamen

    2011-01-01

    Absolute luminosity measurements are of general interest for colliding-beam experiments at storage rings. These measurements are necessary to determine the absolute cross-sections of reaction processes and are valuable to quantify the performance of the accelerator. LHCb has applied two methods to determine the absolute scale of its luminosity measurements for proton-proton collisions at the LHC running at a centre-of-mass energy of 7 TeV. In addition to the classic ``van der Meer'' scan method a novel technique has been developed which makes use of direct imaging of the individual beams using both proton-gas and proton-proton interactions. The beam imaging method is made possible by the high resolution of the LHCb vertex detector and the close proximity of the detector to the beams, and allows beam parameters such as positions, angles and widths to be determined. We describe both methods and compare the two results. In addition, we present the techniques used to transport the absolute luminosity measurement ...

  1. Relativistic Absolutism in Moral Education.

    Science.gov (United States)

    Vogt, W. Paul

    1982-01-01

    Discusses Emile Durkheim's "Moral Education: A Study in the Theory and Application of the Sociology of Education," which holds that morally healthy societies may vary in culture and organization but must possess absolute rules of moral behavior. Compares this moral theory with current theory and practice of American educators. (MJL)

  2. Absolute Standards for Climate Measurements

    Science.gov (United States)

    Leckey, J.

    2016-10-01

    In a world of changing climate, political uncertainty, and ever-changing budgets, the benefit of measurements traceable to SI standards increases by the day. To truly resolve climate change trends on a decadal time scale, on-orbit measurements need to be referenced to something that is both absolute and unchanging. One such mission is the Climate Absolute Radiance and Refractivity Observatory (CLARREO) that will measure a variety of climate variables with an unprecedented accuracy to definitively quantify climate change. In the CLARREO mission, we will utilize phase change cells in which a material is melted to calibrate the temperature of a blackbody that can then be observed by a spectrometer. A material's melting point is an unchanging physical constant that, through a series of transfers, can ultimately calibrate a spectrometer on an absolute scale. CLARREO consists of two primary instruments: an infrared (IR) spectrometer and a reflected solar (RS) spectrometer. The mission will contain orbiting radiometers with sufficient accuracy to calibrate other space-based instrumentation and thus transferring the absolute traceability. The status of various mission options will be presented.

  3. NaNet: a Low-Latency, Real-Time, Multi-Standard Network Interface Card with GPUDirect Features

    CERN Document Server

    Lonardo, A; Ammendola, R; Biagioni, A; Frezza, O; Lamanna, G; Cicero, F Lo; Martinelli, M; Paolucci, P S; Pastorelli, E; Pontisso, L; Rossetti, D; Simeone, F; Simula, F; Sozzi, M; Tosoratto, L; Vicini, P

    2014-01-01

    While the GPGPU paradigm is widely recognized as an effective approach to high performance computing, its adoption in low-latency, real-time systems is still in its early stages. Although GPUs typically show deterministic behaviour in terms of latency in executing computational kernels as soon as data is available in their internal memories, assessment of real-time features of a standard GPGPU system needs careful characterization of all subsystems along data stream path. The networking subsystem results in being the most critical one in terms of absolute value and fluctuations of its response latency. Our envisioned solution to this issue is NaNet, a FPGA-based PCIe Network Interface Card (NIC) design featuring a configurable and extensible set of network channels with direct access through GPUDirect to NVIDIA Fermi/Kepler GPU memories. NaNet design currently supports both standard - GbE (1000BASE-T) and 10GbE (10Base-R) - and custom - 34~Gbps APElink and 2.5~Gbps deterministic latency KM3link - channels, bu...

  4. Auditory generalization gradients for response latency in the monkey1

    Science.gov (United States)

    Moody, David B.; Stebbins, William C.; Iglauer, Carol

    1971-01-01

    Two monkeys were trained to press and hold a response key in the presence of a light and to release it at the onset of a pure tone. Initially, all responses with latencies shorter than 1 sec were reinforced without regard to the frequency of the pure tone, and the intensity of the pure tone that resulted in equal latencies at each frequency was determined. The second stage of the experiment consisted of discrimination training, during which releases to one pure-tone frequency (positive stimulus) were reinforced and releases to a second frequency (negative stimulus) were extinguished. Median latencies to the negative stimulus slowly increased as did the variability of the latency distribution for the negative stimulus. There was no evidence of a concurrent decrease in latencies to the positive stimulus indicative of behavioral contrast. The third part of the experiment consisted of determining maintained generalization gradients by increasing the number of nonreinforcement stimuli. The gradients that eventually resulted showed approximately equal latencies to all frequencies of the negative stimulus and shorter latencies to the positive stimulus frequency. PMID:5003971

  5. Facility Location with Client Latencies: Linear-Programming based Techniques for Minimum-Latency Problems

    CERN Document Server

    Chakrabarty, Deeparnab

    2010-01-01

    We introduce a problem that is a common generalization of the uncapacitated facility location and minimum latency (ML) problems, where facilities need to be opened to serve clients and also need to be sequentially activated before they can provide service. Formally, we are given a set \\F of n facilities with facility-opening costs {f_i}, a set of m clients, and connection costs {c_{ij}} specifying the cost of assigning a client j to a facility i, a root node r denoting the depot, and a time metric d on \\F\\cup{r}. Our goal is to open a subset F of facilities, find a path P starting at r and spanning F to activate the open facilities, and connect each client j to a facility \\phi(j)\\in F, so as to minimize \\sum_{i\\in F}f_i +\\sum_{clients j}(c_{\\phi(j),j}+t_j), where t_j is the time taken to reach \\phi(j) along path P. We call this the minimum latency uncapacitated facility location (MLUFL) problem. Our main result is an O(\\log n\\max{\\log n,\\log m})-approximation for MLUFL. We also show that any improvement in th...

  6. Interaural intensity and latency difference in the dolphin's auditory system.

    Science.gov (United States)

    Popov, V V; Supin AYa

    1991-12-09

    Binaural hearing mechanisms were measured in dolphins (Inia geoffrensis) by recording the auditory nerve evoked response from the body surface. The azimuthal position of a sound source at 10-15 degrees from the longitudinal axis elicited interaural intensity disparity up to 20 dB and interaural latency difference as large as 250 microseconds. The latter was many times greater than the acoustical interaural time delay. This latency difference seems to be caused by the intensity disparity. The latency difference seems to be an effective way of coding of intensity disparity.

  7. Mechanism of latency relaxation in frog skeletal muscle.

    Science.gov (United States)

    Yagi, N

    2011-05-01

    The latency relaxation is a small drop of tension before skeletal muscle begins to develop active tension. This phenomenon was found nearly one century ago but its origin has not been clarified. In this review, the hypotheses for its mechanism are discussed in terms of the recent experimental results using X-ray diffraction. The latency relaxation takes place almost simultaneously as the structural change of the regulatory protein troponin, an unspecified structural change of the thick filament, and increase in stiffness. It seems difficult to associate all of these with the latency relaxation by assuming a simple mechanism. Copyright © 2010 Elsevier Ltd. All rights reserved.

  8. Physics of negative absolute temperatures

    Science.gov (United States)

    Abraham, Eitan; Penrose, Oliver

    2017-01-01

    Negative absolute temperatures were introduced into experimental physics by Purcell and Pound, who successfully applied this concept to nuclear spins; nevertheless, the concept has proved controversial: a recent article aroused considerable interest by its claim, based on a classical entropy formula (the "volume entropy") due to Gibbs, that negative temperatures violated basic principles of statistical thermodynamics. Here we give a thermodynamic analysis that confirms the negative-temperature interpretation of the Purcell-Pound experiments. We also examine the principal arguments that have been advanced against the negative temperature concept; we find that these arguments are not logically compelling, and moreover that the underlying "volume" entropy formula leads to predictions inconsistent with existing experimental results on nuclear spins. We conclude that, despite the counterarguments, negative absolute temperatures make good theoretical sense and did occur in the experiments designed to produce them.

  9. Optomechanics for absolute rotation detection

    Science.gov (United States)

    Davuluri, Sankar

    2016-07-01

    In this article, we present an application of optomechanical cavity for the absolute rotation detection. The optomechanical cavity is arranged in a Michelson interferometer in such a way that the classical centrifugal force due to rotation changes the length of the optomechanical cavity. The change in the cavity length induces a shift in the frequency of the cavity mode. The phase shift corresponding to the frequency shift in the cavity mode is measured at the interferometer output to estimate the angular velocity of absolute rotation. We derived an analytic expression to estimate the minimum detectable rotation rate in our scheme for a given optomechanical cavity. Temperature dependence of the rotation detection sensitivity is studied.

  10. Automatic latency equalization in VHDL-implemented complex pipelined systems

    Science.gov (United States)

    Zabołotny, Wojciech M.

    2016-09-01

    In the pipelined data processing systems it is very important to ensure that parallel paths delay data by the same number of clock cycles. If that condition is not met, the processing blocks receive data not properly aligned in time and produce incorrect results. Manual equalization of latencies is a tedious and error-prone work. This paper presents an automatic method of latency equalization in systems described in VHDL. The proposed method uses simulation to measure latencies and verify introduced correction. The solution is portable between different simulation and synthesis tools. The method does not increase the complexity of the synthesized design comparing to the solution based on manual latency adjustment. The example implementation of the proposed methodology together with a simple design demonstrating its use is available as an open source project under BSD license.

  11. Fast control latency uncertainty elimination for the BESIII ETOF upgrade

    Science.gov (United States)

    Wang, Yun; Cao, Ping; Liu, Shu-bin; An, Qi

    2016-09-01

    A new fanning topology is proposed to precisely fan out fast control signals in the Beijing Spectrometer (BESIII) end-cap time-of-flight (ETOF) electronics. However, uncertainty in transfer latency is introduced by the new fanning channel, which will degrade the precision of fast control. In this paper, latency uncertainty elimination for the BESIII ETOF upgrade is introduced. The latency uncertainty is determined by a Time-Digital-Converter (TDC) embedded in a Field-Programmable Gate Array (FPGA) and is eliminated by re-capturing at synchronous and determinate time. Compared with the existing method of Barrel-cap TOF (BTOF), it has advantages of flexible structure, easy calibration and good adaptability. Field tests on the BESIII ETOF system show that this method effectively eliminates transfer latency uncertainty. Supported by CAS Maintenance Project for Major Scientific and Technological Infrastructure (IHEP-SW-953/2013)

  12. Gyrokinetic Statistical Absolute Equilibrium and Turbulence

    Energy Technology Data Exchange (ETDEWEB)

    Jian-Zhou Zhu and Gregory W. Hammett

    2011-01-10

    A paradigm based on the absolute equilibrium of Galerkin-truncated inviscid systems to aid in understanding turbulence [T.-D. Lee, "On some statistical properties of hydrodynamical and magnetohydrodynamical fields," Q. Appl. Math. 10, 69 (1952)] is taken to study gyrokinetic plasma turbulence: A finite set of Fourier modes of the collisionless gyrokinetic equations are kept and the statistical equilibria are calculated; possible implications for plasma turbulence in various situations are discussed. For the case of two spatial and one velocity dimension, in the calculation with discretization also of velocity v with N grid points (where N + 1 quantities are conserved, corresponding to an energy invariant and N entropy-related invariants), the negative temperature states, corresponding to the condensation of the generalized energy into the lowest modes, are found. This indicates a generic feature of inverse energy cascade. Comparisons are made with some classical results, such as those of Charney-Hasegawa-Mima in the cold-ion limit. There is a universal shape for statistical equilibrium of gyrokinetics in three spatial and two velocity dimensions with just one conserved quantity. Possible physical relevance to turbulence, such as ITG zonal flows, and to a critical balance hypothesis are also discussed.

  13. Signal, Noise, and Variation in Neural and Sensory-Motor Latency.

    Science.gov (United States)

    Lee, Joonyeol; Joshua, Mati; Medina, Javier F; Lisberger, Stephen G

    2016-04-01

    Analysis of the neural code for sensory-motor latency in smooth pursuit eye movements reveals general principles of neural variation and the specific origin of motor latency. The trial-by-trial variation in neural latency in MT comprises a shared component expressed as neuron-neuron latency correlations and an independent component that is local to each neuron. The independent component arises heavily from fluctuations in the underlying probability of spiking, with an unexpectedly small contribution from the stochastic nature of spiking itself. The shared component causes the latency of single-neuron responses in MT to be weakly predictive of the behavioral latency of pursuit. Neural latency deeper in the motor system is more strongly predictive of behavioral latency. A model reproduces both the variance of behavioral latency and the neuron-behavior latency correlations in MT if it includes realistic neural latency variation, neuron-neuron latency correlations in MT, and noisy gain control downstream of MT.

  14. The Role of Spike Temporal Latencies in Artificial Olfaction

    Science.gov (United States)

    Polese, D.; Martinelli, E.; Dini, F.; Paolesse, R.; Filippini, D.; Lundström, I.; Di Natale, C.

    2011-09-01

    In this paper we investigate the recognition power of spike time latencies in an artificial olfactory system. For the scope we used a recently introduced platform for artificial olfaction implementing an artificial olfactory epithelium, formed by thousands sensors, and an abstract olfactory bulb1. Results show that correct volatile compounds classification can be achieved considering only the first two spikes of the neural network output evidencing that the latency of the first spikes contains actually enough information for odor identification.

  15. Human embryonic stem cell lines model experimental human cytomegalovirus latency.

    Science.gov (United States)

    Penkert, Rhiannon R; Kalejta, Robert F

    2013-05-28

    Herpesviruses are highly successful pathogens that persist for the lifetime of their hosts primarily because of their ability to establish and maintain latent infections from which the virus is capable of productively reactivating. Human cytomegalovirus (HCMV), a betaherpesvirus, establishes latency in CD34(+) hematopoietic progenitor cells during natural infections in the body. Experimental infection of CD34(+) cells ex vivo has demonstrated that expression of the viral gene products that drive productive infection is silenced by an intrinsic immune defense mediated by Daxx and histone deacetylases through heterochromatinization of the viral genome during the establishment of latency. Additional mechanistic details about the establishment, let alone maintenance and reactivation, of HCMV latency remain scarce. This is partly due to the technical challenges of CD34(+) cell culture, most notably, the difficulty in preventing spontaneous differentiation that drives reactivation and renders them permissive for productive infection. Here we demonstrate that HCMV can establish, maintain, and reactivate in vitro from experimental latency in cultures of human embryonic stem cells (ESCs), for which spurious differentiation can be prevented or controlled. Furthermore, we show that known molecular aspects of HCMV latency are faithfully recapitulated in these cells. In total, we present ESCs as a novel, tractable model for studies of HCMV latency.

  16. The mTOR Complex Controls HIV Latency.

    Science.gov (United States)

    Besnard, Emilie; Hakre, Shweta; Kampmann, Martin; Lim, Hyung W; Hosmane, Nina N; Martin, Alyssa; Bassik, Michael C; Verschueren, Erik; Battivelli, Emilie; Chan, Jonathan; Svensson, J Peter; Gramatica, Andrea; Conrad, Ryan J; Ott, Melanie; Greene, Warner C; Krogan, Nevan J; Siliciano, Robert F; Weissman, Jonathan S; Verdin, Eric

    2016-12-14

    A population of CD4 T lymphocytes harboring latent HIV genomes can persist in patients on antiretroviral therapy, posing a barrier to HIV eradication. To examine cellular complexes controlling HIV latency, we conducted a genome-wide screen with a pooled ultracomplex shRNA library and in vitro system modeling HIV latency and identified the mTOR complex as a modulator of HIV latency. Knockdown of mTOR complex subunits or pharmacological inhibition of mTOR activity suppresses reversal of latency in various HIV-1 latency models and HIV-infected patient cells. mTOR inhibitors suppress HIV transcription both through the viral transactivator Tat and via Tat-independent mechanisms. This inhibition occurs at least in part via blocking the phosphorylation of CDK9, a p-TEFb complex member that serves as a cofactor for Tat-mediated transcription. The control of HIV latency by mTOR signaling identifies a pathway that may have significant therapeutic opportunities. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Absolute and Convective Ion Beam Instability Studied through Green's Function

    DEFF Research Database (Denmark)

    Jensen, Vagn Orla; Michelsen, Poul; Hsuan, H. C. S.

    1974-01-01

    A Vlasov plasma with a double‐humped, unstable ion velocity distribution function is considered. A δ function in space is assumed as the initial perturbation and the plasma response to this perturbation is calculated, i.e., the Green's function for the problem is found. The response can be divide...... into two parts: a self‐similar, damped part of the form t−1h(x/t), and an unstable, exponentially growing part. The conditions for absolute and convective growth of the latter are discussed....

  18. Android Apps for Absolute Beginners

    CERN Document Server

    Jackson, Wallace

    2011-01-01

    Anybody can start building simple apps for the Android platform, and this book will show you how! Android Apps for Absolute Beginners takes you through the process of getting your first Android applications up and running using plain English and practical examples. It cuts through the fog of jargon and mystery that surrounds Android application development, and gives you simple, step-by-step instructions to get you started.* Teaches Android application development in language anyone can understand, giving you the best possible start in Android development * Provides simple, step-by-step exampl

  19. Reproducibility of multifocal VEP latency using different stimulus presentations.

    Science.gov (United States)

    Sriram, Prema; Klistorner, Alexander; Arvind, Hemamalini; Graham, Stuart L

    2012-08-01

    The aims of the article were to study the reproducibility of latency of multifocal visual evoked potential (mfVEP) recorded using different stimulus presentations and to identify the peak with least variability. Ten normal subjects, aged between 22 and 52 years (mean age 32 ± 8.37 years), participated in the study. All subjects underwent mfVEP testing with pattern reversal and pattern pulse stimulus presentations. The stimulus subtends 26° from fixation and includes 24 segments. Only the vertical channel was recorded on all subjects. Testing was repeated after 1-2 weeks. Only the right eye of all subjects was analysed. Segments with low signal-to-noise ratios (SNR < 1.5) were excluded from analysis. The latencies were analysed to confirm values from the same peak for the two tests. The latency values were then analysed for the start of the response, the first peak and the second peak. The waveforms were reproducible throughout the field. Reproducibility of latency at the "start of the response" was significantly lesser than the first and the second peaks studied, while the reproducibility of latency at the first peak was not statistically different from the second peak for either pattern reversal or pattern pulse stimulation. The latency values were not different between the first and the second sessions for either pattern reversal or pattern pulse stimulation for any of the peaks. The pattern reversal stimulus presentation produced less variability in latency. The first peak is the most reproducible among the three measures in both the stimulus presentation.

  20. An improved approximation ratio for the minimum latency problem

    Energy Technology Data Exchange (ETDEWEB)

    Goemans, M.; Kleinberg, J. [MIT, Cambridge, MA (United States)

    1996-12-31

    Given a tour visiting n points in a metric space, the latency of one of these points p is the distance traveled in the tour before reaching p. The minimum latency problem asks for a tour passing through n given points for which the total latency of the n points is minimum; in effect, we are seeking the tour with minimum average {open_quotes}arrival time.{close_quotes} This problem has been studied in the operations research literature, where it has also been termed the {open_quotes}delivery-man problem{close_quotes} and the {open_quotes}traveling repairman problem.{close_quotes} The approximability of the minimum latency problem was first considered by Sahni and Gonzalez in 1976; however, unlike the classical traveling salesman problem, it is not easy to give any constant-factor approximation algorithm for the minimum latency problem. Recently, Blum, Chalasani, Coppersmith, Pulleyblank, Raghavan, and Sudan gave the first such algorithm, obtaining an approximation ratio of 144. In this work, we present an algorithm which improves this ratio to 21.55. The development of our algorithm involves a number of techniques that seem to be of interest from the perspective of the traveling salesman problem and its variants more generally.

  1. An evolutionary role for HIV latency in enhancing viral transmission.

    Science.gov (United States)

    Rouzine, Igor M; Weinberger, Ariel D; Weinberger, Leor S

    2015-02-26

    HIV latency is the chief obstacle to eradicating HIV but is widely believed to be an evolutionary accident providing no lentiviral fitness advantage. However, findings of latency being "hardwired" into HIV's gene-regulatory circuitry appear inconsistent with latency being an evolutionary accident, given HIV's rapid mutation rate. Here, we propose that latency is an evolutionary "bet-hedging" strategy whose frequency has been optimized to maximize lentiviral transmission by reducing viral extinction during mucosal infections. The model quantitatively fits the available patient data, matches observations of high-frequency latency establishment in cell culture and primates, and generates two counterintuitive but testable predictions. The first prediction is that conventional CD8-depletion experiments in SIV-infected macaques increase latent cells more than viremia. The second prediction is that strains engineered to have higher replicative fitness—via reduced latency—will exhibit lower infectivity in animal-model mucosal inoculations. Therapeutically, the theory predicts treatment approaches that may substantially enhance "activate-and-kill" HIV-cure strategies. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Effects of lorazepam on short latency afferent inhibition and short latency intracortical inhibition in humans.

    Science.gov (United States)

    Di Lazzaro, V; Oliviero, A; Saturno, E; Dileone, M; Pilato, F; Nardone, R; Ranieri, F; Musumeci, G; Fiorilla, T; Tonali, P

    2005-04-15

    Experimental studies have demonstrated that the GABAergic system modulates acetylcholine release and, through GABA(A) receptors, tonically inhibits cholinergic activity. Little is known about the effects of GABA on the cholinergic activity in the human central nervous system. In vivo evaluation of some cholinergic circuits of the human brain has recently been introduced using a transcranial magnetic stimulation (TMS) protocol based on coupling peripheral nerve stimulation with TMS of the motor cortex. Peripheral nerve inputs have an inhibitory effect on motor cortex excitability at short intervals (short latency afferent inhibition, SAI). We investigated whether GABA(A) activity enhancement by lorazepam modifies SAI. We also evaluated the effects produced by lorazepam on a different TMS protocol of cortical inhibition, the short interval intracortical inhibition (SICI), which is believed to be directly related to GABA(A) activity. In 10 healthy volunteers, the effects of lorazepam were compared with those produced by quetiapine, a psychotropic drug with sedative effects with no appreciable affinity at cholinergic muscarinic and benzodiazepine receptors, and with those of a placebo using a randomized double-blind study design. Administration of lorazepam produced a significant increase in SICI (F(3,9) = 3.19, P = 0.039). In contrast to SICI, SAI was significantly reduced by lorazepam (F(3,9) = 9.39, P = 0.0002). Our findings demonstrate that GABA(A) activity enhancement determines a suppression of SAI and an increase of SICI.

  3. Predicting naming latencies for action pictures: Dutch norms.

    Science.gov (United States)

    Shao, Zeshu; Roelofs, Ardi; Meyer, Antje S

    2014-03-01

    The present study provides Dutch norms for age of acquisition, familiarity, imageability, image agreement, visual complexity, word frequency, and word length (in syllables) for 124 line drawings of actions. Ratings were obtained from 117 Dutch participants. Word frequency was determined on the basis of the SUBTLEX-NL corpus (Keuleers, Brysbaert, & New, Behavior Research Methods, 42, 643-650, 2010). For 104 of the pictures, naming latencies and name agreement were determined in a separate naming experiment with 74 native speakers of Dutch. The Dutch norms closely corresponded to the norms for British English. Multiple regression analysis showed that age of acquisition, imageability, image agreement, visual complexity, and name agreement were significant predictors of naming latencies, whereas word frequency and word length were not. Combined with the results of a principal-component analysis, these findings suggest that variables influencing the processes of conceptual preparation and lexical selection affect latencies more strongly than do variables influencing word-form encoding.

  4. Mechanisms of Kaposi's Sarcoma-Associated Herpesvirus Latency and Reactivation

    Directory of Open Access Journals (Sweden)

    Fengchun Ye

    2011-01-01

    Full Text Available The life cycle of Kaposi's sarcoma-associated herpesvirus (KSHV consists of latent and lytic replication phases. During latent infection, only a limited number of KSHV genes are expressed. However, this phase of replication is essential for persistent infection, evasion of host immune response, and induction of KSHV-related malignancies. KSHV reactivation from latency produces a wide range of viral products and infectious virions. The resulting de novo infection and viral lytic products modulate diverse cellular pathways and stromal microenvironment, which promote the development of Kaposi's sarcoma (KS. The mechanisms controlling KSHV latency and reactivation are complex, involving both viral and host factors, and are modulated by diverse environmental factors. Here, we review the cellular and molecular basis of KSHV latency and reactivation with a focus on the most recent advancements in the field.

  5. Fast Control Latency Uncertainty Elimination for BESIII ETOF Upgrade

    CERN Document Server

    Wang, Yun; Liu, Shubin; An, Qi

    2016-01-01

    Under upgrade program of Beijing Spectrometer (BES III) end-cap time of flight (ETOF), which makes the total electronic channels increasing greatly. To fan out fast control signals precisely to new ETOF electronics, new fanning out scheme based on technique of high serial communication is used for upgraded ETOF and for barrel TOF meanwhile. However, uncertainty of transfer latency is introduced by the SerDes chip, which will degrade the precision of fast control. In this paper, a new method of latency uncertainty elimination is proposed. This method has advantages of flexible structure, easy for calibration, little resource cost and ability of multi-channel application. Field tests on BES III ETOF system shows that this method can eliminate transfer latency uncertainty effectively.

  6. Effects of psychot herapy on REM latency and REM time.

    Science.gov (United States)

    Karle, W; Hopper, M; Switzer, A; Corriere, R; Woldenberg, L

    1980-08-01

    This study investigated the effect of a functional psychotherapy on the sleep EEG patterns of 6 patients. Contrary to original expectations no significant group differences in REM time and REM latency were found between two nights following therapy sessions and two normal nights. However, across the 4 nights the patients exhibited an average REM latency of 71 min. which was significantly shorter than that recorded in an independent study with the same design and a similar subject population. Clausen, Sersen, and Lidsky (1974) reported an average REM latency of 107.3 min. for 10 normal subjects also recorded across four nights. This result is compared with those in several other studies and discussed in relation to possible changes in dream patterns.

  7. Cosmology with Negative Absolute Temperatures

    CERN Document Server

    Vieira, J P P; Lewis, Antony

    2016-01-01

    Negative absolute temperatures (NAT) are an exotic thermodynamical consequence of quantum physics which has been known since the 1950's (having been achieved in the lab on a number of occasions). Recently, the work of Braun et al (2013) has rekindled interest in negative temperatures and hinted at a possibility of using NAT systems in the lab as dark energy analogues. This paper goes one step further, looking into the cosmological consequences of the existence of a NAT component in the Universe. NAT-dominated expanding Universes experience a borderline phantom expansion ($w<-1$) with no Big Rip, and their contracting counterparts are forced to bounce after the energy density becomes sufficiently large. Both scenarios might be used to solve horizon and flatness problems analogously to standard inflation and bouncing cosmologies. We discuss the difficulties in obtaining and ending a NAT-dominated epoch, and possible ways of obtaining density perturbations with an acceptable spectrum.

  8. Cosmology with negative absolute temperatures

    Science.gov (United States)

    Vieira, J. P. P.; Byrnes, Christian T.; Lewis, Antony

    2016-08-01

    Negative absolute temperatures (NAT) are an exotic thermodynamical consequence of quantum physics which has been known since the 1950's (having been achieved in the lab on a number of occasions). Recently, the work of Braun et al. [1] has rekindled interest in negative temperatures and hinted at a possibility of using NAT systems in the lab as dark energy analogues. This paper goes one step further, looking into the cosmological consequences of the existence of a NAT component in the Universe. NAT-dominated expanding Universes experience a borderline phantom expansion (w inflation and bouncing cosmologies. We discuss the difficulties in obtaining and ending a NAT-dominated epoch, and possible ways of obtaining density perturbations with an acceptable spectrum.

  9. Pudendal nerve latency time in normal women via intravaginal stimulation

    Directory of Open Access Journals (Sweden)

    Geraldo A. Cavalcanti

    2006-12-01

    Full Text Available INTRODUCTION & OBJECTIVES: Studies of motor conduction for the efferent functional assessment of the pudendal nerve in women with pelvic dysfunctions have been conducted through researching distal motor latency times. The transrectal approach has been the classic approach for this electrophysiological examination. The objective of the present study is to verify the viability of the transvaginal approach in performing the exam, to establish normal values for this method and to analyze the influence of age, stature and parity in the latency value of normal women. MATERIALS AND METHODS: A total of 23 volunteers without genitourinary pathologies participated in this study. In each, pudendal motor latency was investigated through the transvaginal approach, which was chosen due to patient’s higher tolerance levels. RESULTS: The motor response represented by registering the M-wave was obtained in all volunteers on the right side (100% and in 13 volunteers on the left side (56.5%. The mean motor latency obtained in the right and left was respectively: 1.99 ± 0.41 and 1.92 ± 0.48 milliseconds (ms. There was no difference between the sides (p = 0.66. Latency did not correlate with age, stature or obstetric history. The results obtained in the present study were in agreement with those found by other researchers using the transrectal approach. CONCLUSION: The vaginal approach represents an alternative for pudendal nerve distal motor latency time, with similar results to those achieved through the transrectal approach. Normative values obtained herein might serve as a comparative basis for subsequent physiopathological studies.

  10. Scalla: Structured Cluster Architecture for Low Latency Access

    Energy Technology Data Exchange (ETDEWEB)

    Hanushevsky, Andrew; Wang, Daniel L.; /SLAC

    2012-03-20

    Scalla is a distributed low-latency file access system that incorporates novel techniques that minimize latency and maximize scalability over a large distributed system with a distributed namespace. Scalla's techniques have shown to be effective in nearly a decade of service for the high-energy physics community using commodity hardware and interconnects. We describe the two components used in Scalla that are instrumental in its ability to provide low-latency, fault-tolerant name resolution and load distribution, and enable its use as a high-throughput, low-latency communication layer in the Qserv system, the Large Synoptic Survey Telescope's (LSST's) prototype astronomical query system. Scalla arguably exceeded its three main design objectives: low latency, scaling, and recoverability. In retrospect, these objectives were met using a simple but effective design. Low latency was met by uniformly using linear or constant time algorithms in all high-use paths, avoiding locks whenever possible, and using compact data structures to maximize the memory caching efficiency. Scaling was achieved by architecting the system as a 64-ary tree. Nodes can be added easily and as the number of nodes increases, search performance increases at an exponential rate. Recoverability is inherent in that no permanent state information is maintained and whatever state information is needed it can be quickly constructed or reconstructed in real time. This allows dynamic changes in a cluster of servers with little impact on over-all performance or usability. Today, Scalla is being deployed in environments and for uses that were never conceived in 2001. This speaks well for the systems adaptability but the underlying reason is that the system can meet its three fundamental objectives at the same time.

  11. Ranitidine: single dose pharmacokinetics and absolute bioavailability in man.

    Science.gov (United States)

    van Hecken, A M; Tjandramaga, T B; Mullie, A; Verbesselt, R; de Schepper, P J

    1982-08-01

    1 Ranitidine single dose pharmacokinetics and absolute bioavailability have been studied in five healthy male volunteers. Following an overnight fast, 150 mg was given intravenously as a bolus injection or orally as a tablet formulation to each subject on separate occasions. 2 Following intravenous administration, plasma levels declined biexponentially. The mean (+/- s.d.) distribution half-life (t 1/2 alpha) was 6.6 +/- 1.6 min; plasma half-life (t 1/2 beta) was 1.7 +/- 0.2 h; the volume of distribution (V) was 96 +/- 9 1; total body clearance (CL) was 647 +/- 94 ml/min and renal clearance (CLR) 520 +/- 123 ml/min. 3 Following oral administration plasma levels showed a bimodal pattern with a first peak at 1.1 +/- 0.4 h and a second peak at 3 +/- 0 h. The absolute availability was 60 +/- 17%. The plasma half-life (t 1/2) of 2.3 +/- 0.4 h was significantly longer (P less than 0.05) after oral than after i.v. administration. 4 Renal excretion of unchanged ranitidine accounted for 79 +/- 9% of the dose after i.v. administration and for 27 +/- 7% after oral administration. 5 Our results suggest a more extensive biotransformation of ranitidine and biliary excretion of metabolites after oral administration while i.v. administration ranitidine is preferentially excreted unchanged in the urine.

  12. Absolutely separating quantum maps and channels

    Science.gov (United States)

    Filippov, S. N.; Magadov, K. Yu; Jivulescu, M. A.

    2017-08-01

    Absolutely separable states ϱ remain separable under arbitrary unitary transformations U\\varrho {U}\\dagger . By example of a three qubit system we show that in a multipartite scenario neither full separability implies bipartite absolute separability nor the reverse statement holds. The main goal of the paper is to analyze quantum maps resulting in absolutely separable output states. Such absolutely separating maps affect the states in a way, when no Hamiltonian dynamics can make them entangled afterwards. We study the general properties of absolutely separating maps and channels with respect to bipartitions and multipartitions and show that absolutely separating maps are not necessarily entanglement breaking. We examine the stability of absolutely separating maps under a tensor product and show that {{{Φ }}}\\otimes N is absolutely separating for any N if and only if Φ is the tracing map. Particular results are obtained for families of local unital multiqubit channels, global generalized Pauli channels, and combination of identity, transposition, and tracing maps acting on states of arbitrary dimension. We also study the interplay between local and global noise components in absolutely separating bipartite depolarizing maps and discuss the input states with high resistance to absolute separability.

  13. Hippocampal serotonin responses in short and long attack latency mice

    NARCIS (Netherlands)

    van Riel, E; Meijer, OC; Veenema, AH; Joëls, M

    2002-01-01

    Short and long attack latency mice, which are selected based on their offensive behaviour in a resident-intruder model, differ in their neuroendocrine regulation as well as in aspects of their brain serotonin system. Previous studies showed that the binding capacity and expression of serotonin-1A re

  14. Low latency IP mobility management: protocol and analysis

    Directory of Open Access Journals (Sweden)

    Guo Xiaobing

    2011-01-01

    Full Text Available Abstract Mobile IP is one of the dominating protocols that enable a mobile node to remain reachable while moving around in the Internet. However, it suffers from long handoff latency and route inefficiency. In this article, we present a novel distributed mobility management architecture, ADA (Asymmetric Double-Agents, which introduces double mobility agents to serve one end-to-end communication. One mobility agent is located close to the MN and the other close to the CN. ADA can achieve both low handoff latency and low transmission latency, which is crucial for improvement of user perceived QoS. It also provides an easy-to-use mechanism for MNs to manage and control each traffic session with a different policy and provide specific QoS support. We apply ADA to MIPv6 communications and present a detailed protocol design. Subsequently, we propose an analytical framework for systematic and thorough performance evaluation of mobile IP-based mobility management protocols. Equipped with this model, we analyze the handoff latency, single interaction delay and total time cost under the bidirectional tunneling mode and the route optimization mode for MIPv6, HMIPv6, CNLP, and ADA. Through both quantitative analysis and NS2-based simulations, we show that ADA significantly outperforms the existing mobility management protocols.

  15. Optimizing latency in Xilinx FPGA implementations of the GBT

    CERN Document Server

    Muschter, S; Bohm, C; Cachemiche, J-P; Baron, S

    2010-01-01

    The GigaBit Transceiver (GBT) {[}1] system has been developed to replace the Timing, Trigger and Control (TTC) system {[}2], currently used by LHC, as well as to provide data transmission between on-detector and off-detector components in future sLHC detectors. A VHDL version of the GBT-SERDES, designed for FPGAs, was released in March 2010 as a GBT-FPGA Starter Kit for future GBT users and for off-detector GBT implementation {[}3]. This code was optimized for resource utilization {[}4], as the GBT protocol is very demanding. It was not, however, optimized for latency - which will be a critical parameter when used in the trigger path. The GBT-FPGA Starter Kit firmware was first analyzed in terms of latency by looking at the separate components of the VHDL version. Once the parts which contribute most to the latency were identified and modified, two possible optimizations were chosen, resulting in a latency reduced by a factor of three. The modifications were also analyzed in terms of logic utilization. The la...

  16. Monitoring data transfer latency in CMS computing operations

    CERN Document Server

    Bonacorsi, D; Magini, N; Sartirana, A; Taze, M; Wildish, T

    2015-01-01

    During the first LHC run, the CMS experiment collected tens of Petabytes of collision and simulated data, which need to be distributed among dozens of computing centres with low latency in order to make efficient use of the resources. While the desired level of throughput has been successfully achieved, it is still common to observe transfer workflows that cannot reach full completion in a timely manner due to a small fraction of stuck files which require operator intervention.For this reason, in 2012 the CMS transfer management system, PhEDEx, was instrumented with a monitoring system to measure file transfer latencies, and to predict the completion time for the transfer of a data set. The operators can detect abnormal patterns in transfer latencies while the transfer is still in progress, and monitor the long-term performance of the transfer infrastructure to plan the data placement strategy.Based on the data collected for one year with the latency monitoring system, we present a study on the different fact...

  17. Characterising the association of latency with α1-antitrypsin polymerisation using a novel monoclonal antibody

    Science.gov (United States)

    Tan, Lu; Perez, Juan; Mela, Marianna; Miranda, Elena; Burling, Keith A; Rouhani, Farshid N; DeMeo, Dawn L; Haq, Imran; Irving, James A; Ordóñez, Adriana; Dickens, Jennifer A; Brantly, Mark; Marciniak, Stefan J; Alexander, Graeme J M; Gooptu, Bibek; Lomas, David A

    2015-01-01

    α1-Antitrypsin is primarily synthesised in the liver, circulates to the lung and protects pulmonary tissues from proteolytic damage. The Z mutant (Glu342Lys) undergoes inactivating conformational change and polymerises. Polymers are retained within the hepatocyte endoplasmic reticulum (ER) in homozygous (PiZZ) individuals, predisposing the individuals to hepatic cirrhosis and emphysema. Latency is an analogous process of inactivating, intra-molecular conformational change and may co-occur with polymerisation. However, the relationship between latency and polymerisation remained unexplored in the absence of a suitable probe. We have developed a novel monoclonal antibody specific for latent α1-antitrypsin and used it in combination with a polymer-specific antibody, to assess the association of both conformers in vitro, in disease and during augmentation therapy. In vitro kinetics analysis showed polymerisation dominated the pathway but latency could be promoted by stabilising monomeric α1-antitrypsin. Polymers were extensively produced in hepatocytes and a cell line expressing Z α1-antitrypsin but the latent protein was not detected despite manipulation of the secretory pathway. However, α1-antitrypsin augmentation therapy contains latent α1-antitrypsin, as did the plasma of 63/274 PiZZ individuals treated with augmentation therapy but 0/264 who were not receiving this medication (p < 10−14). We conclude that latent α1-antitrypsin is a by-product of the polymerisation pathway, that the intracellular folding environment is resistant to formation of the latent conformer but that augmentation therapy introduces latent α1-antitrypsin into the circulation. A suite of monoclonal antibodies and methodologies developed in this study can characterise α1-antitrypsin folding and conformational transitions, and screen methods to improve augmentation therapy. PMID:25462157

  18. Absolute configuration of isovouacapenol C

    Directory of Open Access Journals (Sweden)

    Hoong-Kun Fun

    2010-08-01

    Full Text Available The title compound, C27H34O5 {systematic name: (4aR,5R,6R,6aS,7R,11aS,11bR-4a,6-dihydroxy-4,4,7,11b-tetramethyl-1,2,3,4,4a,5,6,6a,7,11,11a,11b-dodecahydrophenanthro[3,2-b]furan-5-yl benzoate}, is a cassane furanoditerpene, which was isolated from the roots of Caesalpinia pulcherrima. The three cyclohexane rings are trans fused: two of these are in chair conformations with the third in a twisted half-chair conformation, whereas the furan ring is almost planar (r.m.s. deviation = 0.003 Å. An intramolecular C—H...O interaction generates an S(6 ring. The absolute configurations of the stereogenic centres at positions 4a, 5, 6, 6a, 7, 11a and 11b are R, R, R, S, R, S and R, respectively. In the crystal, molecules are linked into infinite chains along [010] by O—H...O hydrogen bonds. C...O [3.306 (2–3.347 (2 Å] short contacts and C—H...π interactions also occur.

  19. Measurement of the absolute speed is possible?

    OpenAIRE

    Shevchenko, Sergey V.; Vladimir V. Tokarevsky

    2016-01-01

    One of popular problems, which  are experimentally studied in physics in a long time, is the testing of the special relativity theory, first of all – measurements of isotropy and constancy of light speed; as well as attempts to determine so called “absolute speed”, i.e. the Earth speed in the absolute spacetime (absolute reference frame), if this spacetime (ARF) exists.  Corresponding experiments aimed at the measuring of proper speed of some reference frame in oth...

  20. To measure the absolute speed is possible?

    OpenAIRE

    Shevchenko, Sergey; Tokarevsky, Vladimir

    2013-01-01

    One of popular problems, which are experimentally studied in physics in a long time, is the testing of the special relativity theory, first of all – measurements of isotropy and constancy of light speed; as well as attempts to determine so called “absolute speed”, i.e. the Earth speed in the absolute spacetime (absolute reference frame), if this spacetime (ARF) exists. Corresponding experiments aimed at the measuring of proper speed of some reference frame in other one, incl...

  1. Modeling neuroendocrine stress reactivity in salivary cortisol: adjusting for peak latency variability.

    Science.gov (United States)

    Lopez-Duran, Nestor L; Mayer, Stefanie E; Abelson, James L

    2014-07-01

    In this report, we present growth curve modeling (GCM) with landmark registration as an alternative statistical approach for the analysis of time series cortisol data. This approach addresses an often-ignored but critical source of variability in salivary cortisol analyses: individual and group differences in the time latency of post-stress peak concentrations. It allows for the simultaneous examination of cortisol changes before and after the peak while controlling for timing differences, and thus provides additional information that can help elucidate group differences in the underlying biological processes (e.g., intensity of response, regulatory capacity). We tested whether GCM with landmark registration is more sensitive than traditional statistical approaches (e.g., repeated measures ANOVA--rANOVA) in identifying sex differences in salivary cortisol responses to a psychosocial stressor (Trier Social Stress Test--TSST) in healthy adults (mean age 23). We used plasma ACTH measures as our "standard" and show that the new approach confirms in salivary cortisol the ACTH finding that males had longer peak latencies, higher post-stress peaks but a more intense post-peak decline. This finding would have been missed if only saliva cortisol was available and only more traditional analytic methods were used. This new approach may provide neuroendocrine researchers with a highly sensitive complementary tool to examine the dynamics of the cortisol response in a way that reduces risk of false negative findings when blood samples are not feasible.

  2. A Detailed Chunk-Level Performance Study of Web Page Retrieve Latency

    Institute of Scientific and Technical Information of China (English)

    XIE Hai-guang; LI Jian-hua; LI Xiang

    2005-01-01

    It is a widely discussed question that where the web latency comes from. In this paper, we propose a novel chunk-level latency dependence model to give a better illustration of the web latency. Based on the fact that web content is delivered in chunk sequence, and clients care more about whole page retrieval latency, this paper carries out a detailed study on how the chunk sequence and relations affect the web retrieval latency. A series of thorough experiments are also conducted and data analysis are also made. The result is useful for further study on how to reduce the web latency.

  3. Absolute Income, Relative Income, and Happiness

    Science.gov (United States)

    Ball, Richard; Chernova, Kateryna

    2008-01-01

    This paper uses data from the World Values Survey to investigate how an individual's self-reported happiness is related to (i) the level of her income in absolute terms, and (ii) the level of her income relative to other people in her country. The main findings are that (i) both absolute and relative income are positively and significantly…

  4. Newton On Absolute Space A Commentary

    CERN Document Server

    Adewole, A I A

    2001-01-01

    Newton seems to have stated a quantitative relationship between the position of a body in relative space and the position of the body in absolute space in the first scholium of his Principia. We show that if this suspected relationship is assumed to hold, it will dispel many errors and misrepresentations that have befallen Newton's ideas on absolute space.

  5. Investigating Absolute Value: A Real World Application

    Science.gov (United States)

    Kidd, Margaret; Pagni, David

    2009-01-01

    Making connections between various representations is important in mathematics. In this article, the authors discuss the numeric, algebraic, and graphical representations of sums of absolute values of linear functions. The initial explanations are accessible to all students who have experience graphing and who understand that absolute value simply…

  6. Monolithically integrated absolute frequency comb laser system

    Energy Technology Data Exchange (ETDEWEB)

    Wanke, Michael C.

    2016-07-12

    Rather than down-convert optical frequencies, a QCL laser system directly generates a THz frequency comb in a compact monolithically integrated chip that can be locked to an absolute frequency without the need of a frequency-comb synthesizer. The monolithic, absolute frequency comb can provide a THz frequency reference and tool for high-resolution broad band spectroscopy.

  7. Performance Evaluation of L3 Handover Latency in MIPv6

    Directory of Open Access Journals (Sweden)

    D.Kavitha,

    2011-06-01

    Full Text Available Recent years in the field of mobile communications have brought two significant requirements – seamless service delivery and Quality of Service provisioning. Seamless mobility goes hand in hand withMobile IPv6 protocol and various handover schemes of this protocol are trying to solve the QoS issue. In this paper we are presenting a method for evaluation of the Layer 3 handover schemes from the handover latency point of view. A L3 handover procedure can be divided into four phases: Movement Detection, CoA Configuration, Home agent Registration and Route Optimization. We simulated the proposed protocol certificate based on Demand Approach in Route Optimization phase and compared it with the return routability procedure in Route Optimization phase of MIPv6 handover. The latencies in different handover phases have been measured in an operated wireless LAN (WLAN in order to determine the performance bottleneck of handover.

  8. A review of the methods for neuronal response latency estimation

    DEFF Research Database (Denmark)

    Levakovaa, Marie; Tamborrino, Massimiliano; Ditlevsen, Susanne;

    2015-01-01

    Neuronal response latency is usually vaguely defined as the delay between the stimulus onset and the beginning of the response. It contains important information for the understanding of the temporal code. For this reason, the detection of the response latency has been extensively studied...... in the last twenty years, yielding different estimation methods. They can be divided into two classes, one of them including methods based on detecting an intensity change in the firing rate profile after the stimulus onset and the other containing methods based on detection of spikes evoked...... by the stimulation using interspike intervals and spike times. The aim of this paper is to present a review of the main techniques proposed in both classes, highlighting their advantages and shortcomings....

  9. Rewards modulate saccade latency but not exogenous spatial attention.

    Directory of Open Access Journals (Sweden)

    Stephen eDunne

    2015-07-01

    Full Text Available The eye movement system is sensitive to reward. However, whilst the eye movement system is extremely flexible, the extent to which changes to oculomotor behaviour induced by reward paradigms persist beyond the training period or transfer to other oculomotor tasks is unclear. To address these issues we examined the effects of presenting feedback that represented small monetary rewards to spatial locations on the latency of saccadic eye movements, the time-course of learning and extinction of the effects of rewarding saccades on exogenous spatial attention and oculomotor IOR. Reward feedback produced a relative facilitation of saccadic latency in a stimulus driven saccade task which persisted for 3 blocks of extinction trials. However this hemifield-specific effect failed to transfer to peripheral cueing tasks. We conclude that rewarding specific spatial locations is unlikely to induce long-term, systemic changes to the human oculomotor or attention systems.

  10. A novel reversible carry-selected adder with low latency

    Science.gov (United States)

    Li, Ming-Cui; Zhou, Ri-Gui

    2016-07-01

    Reversible logic is getting more and more attention in quantum computing, optical computing, nanotechnology and low-power complementary metal oxide semiconductor designs since reversible circuits do not loose information during computation and have only small energy dissipation. In this paper, a novel carry-selected reversible adder is proposed primarily optimised for low latency. A 4-bit reversible full adder with two kinds of outputs, minimum delay and optimal quantum cost is presented as the building block for ?-bit reversible adder. Three new reversible gates NPG (new Peres gate), TEPG (triple extension of Peres gate) and RMUX21 (reversible 2-to-1 multiplexer) are proposed and utilised to design efficient adder units. The secondary carry propagation chain is carefully designed to reduce the time consumption. The novelty of the proposed design is the consideration of low latency. The comparative study shows that the proposed adder achieves the improvement from 61.46% to 95.29% in delay over the existing designs.

  11. Fundamental Tradeoffs among Reliability, Latency and Throughput in Cellular Networks

    DEFF Research Database (Denmark)

    Soret, Beatriz; Mogensen, Preben; Pedersen, Klaus I.

    2014-01-01

    We address the fundamental tradeoffs among latency, reliability and throughput in a cellular network. The most important elements influencing the KPIs in a 4G network are identified, and the inter-relationships among them is discussed. We use the effective bandwidth and the effective capacity...... theory as analytical framework for calculating the maximum achievable rate for a given latency and reliability constraint. The analysis is conducted in a simplified LTE network, providing baseline - yet powerful - insight of the main tradeoffs. Guidelines to extend the theory to more complex systems...... are also presented, including a semi-analytical approach for cases with intractable channel and traffic models. We also discuss the use of system-level simulations to explore the limits of LTE networks. Based on our findings, we give some recommendations for the imminent 5G technology design phase...

  12. Low latency remote memory access on the Intel Paragon

    Energy Technology Data Exchange (ETDEWEB)

    Rosing, M. [Pacific Northwest Lab., Richland, WA (United States); Pierce, P. [Idaho National Engineering Lab., Idaho Falls, ID (United States)

    1994-06-20

    We describe a cooperative project between Pacific Northwest Laboratory and Intel on providing low latency communications on the Intel Paragon. Our interest is in developing modules that are tailored to specific types of communication and are optimized for these cases. The modules described are implemented as simple extensions to the Paragon operating system. The first extension supports remote reads, writes, and accumulates on subsections of matrices. This module is intended to be used where the communication pattern is not known until run time. The second extension is designed to support low latency communication for short messages in a pipelined fashion. Finally, an interface for doing highly structured communication where the patterns of communication are well understood ahead of time is described. This is intended to be used in global communications such as global reduction.

  13. Stochastic Game Analysis and Latency Awareness for Self-Adaptation

    Science.gov (United States)

    2014-01-01

    Tactic: is a primitive action that corresponds to a single step of adaptation, and has an associated: (i) cost/benefit impact on the different quality...dimensions, and (ii) latency, which corresponds to the time it takes since a tactic is started until its effect is observed.2 For instance, in... Gandhi et al. considers the setup time of servers, and is able to deal with unpredictable changes in load by be- ing conservative about removing servers

  14. Herpes Simplex Virus Latency: The DNA Repair-Centered Pathway

    Directory of Open Access Journals (Sweden)

    Jay C. Brown

    2017-01-01

    Full Text Available Like all herpesviruses, herpes simplex virus 1 (HSV1 is able to produce lytic or latent infections depending on the host cell type. Lytic infections occur in a broad range of cells while latency is highly specific for neurons. Although latency suggests itself as an attractive target for novel anti-HSV1 therapies, progress in their development has been slowed due in part to a lack of agreement about the basic biochemical mechanisms involved. Among the possibilities being considered is a pathway in which DNA repair mechanisms play a central role. Repair is suggested to be involved in both HSV1 entry into latency and reactivation from it. Here I describe the basic features of the DNA repair-centered pathway and discuss some of the experimental evidence supporting it. The pathway is particularly attractive because it is able to account for important features of the latent response, including the specificity for neurons, the specificity for neurons of the peripheral compared to the central nervous system, the high rate of genetic recombination in HSV1-infected cells, and the genetic identity of infecting and reactivated virus.

  15. Using Arduino microcontroller boards to measure response latencies.

    Science.gov (United States)

    Schubert, Thomas W; D'Ausilio, Alessandro; Canto, Rosario

    2013-12-01

    Latencies of buttonpresses are a staple of cognitive science paradigms. Often keyboards are employed to collect buttonpresses, but their imprecision and variability decreases test power and increases the risk of false positives. Response boxes and data acquisition cards are precise, but expensive and inflexible, alternatives. We propose using open-source Arduino microcontroller boards as an inexpensive and flexible alternative. These boards connect to standard experimental software using a USB connection and a virtual serial port, or by emulating a keyboard. In our solution, an Arduino measures response latencies after being signaled the start of a trial, and communicates the latency and response back to the PC over a USB connection. We demonstrated the reliability, robustness, and precision of this communication in six studies. Test measures confirmed that the error added to the measurement had an SD of less than 1 ms. Alternatively, emulation of a keyboard results in similarly precise measurement. The Arduino performs as well as a serial response box, and better than a keyboard. In addition, our setup allows for the flexible integration of other sensors, and even actuators, to extend the cognitive science toolbox.

  16. Latencies of extracted distortion-product otoacoustic source components

    Science.gov (United States)

    Zelle, Dennis; Thiericke, John P.; Gummer, Anthony W.; Dalhoff, Ernst

    2015-12-01

    Distortion product otoacoustic emissions (DPOAEs) evolve as a byproduct of the nonlinear amplification process of two stimulus tones f2 ≥ f1 in the cochlea. According to a prevailing model, DPOAEs comprise a nonlinear-generation and a coherent-reflection component. Recently, we introduced a new technique using short f2 pulses which enables the extraction of both source components in the time domain by nonlinear least-square curve fitting to decompose the DPOAE response into pulse basis functions (PBFs). The analysis of the extracted DPOAE source components in the time domain enables determination of their latencies which may be used to estimate cochlear frequency tuning. Short-pulse DPOAEs were acquired from 16 subjects for f2 = 1.5, 2, 3, and 4 kHz using six primary-tone levels with L2 = 25 - 65 dB SPL. For the extracted nonlinear-generation and coherent-reflection components, latencies decrease with increasing stimulus frequency and level. The obtained latency values are in accordance with the expected behavior of the cochlear amplifier and may provide an additional diagnostic parameter to assess frequency tuning.

  17. HTLV-1 Tax activates HIV-1 transcription in latency models.

    Science.gov (United States)

    Geddes, Victor Emmanuel Viana; José, Diego Pandeló; Leal, Fabio E; Nixon, Douglas F; Tanuri, Amilcar; Aguiar, Renato Santana

    2017-04-01

    HIV-1 latency is a major obstacle to HIV-1 eradication. Coinfection with HTLV-1 has been associated with faster progression to AIDS. HTLV-1 encodes the transactivator Tax which can activate both HTLV-1 and HIV-1 transcription. Here, we demonstrate that Tax activates HIV transcription in latent CD4(+) T cells. Tax promotes the activation of P-TEFb, releasing CDK9 and Cyclin T1 from inactive forms, promoting transcription elongation and reactivation of latent HIV-1. Tax mutants lacking interaction with the HIV-1-LTR promoter were not able to activate P-TEFb, with no subsequent activation of latent HIV. In HIV-infected primary resting CD4(+) T cells, Tax-1 reactivated HIV-1 transcription up to five fold, confirming these findings in an ex vivo latency model. Finally, our results confirms that HTLV-1/Tax hijacks cellular partners, promoting HIV-1 transcription, and this interaction should be further investigated in HIV-1 latency studies in patients with HIV/HTLV-1 co-infection. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. SMYD2-Mediated Histone Methylation Contributes to HIV-1 Latency.

    Science.gov (United States)

    Boehm, Daniela; Jeng, Mark; Camus, Gregory; Gramatica, Andrea; Schwarzer, Roland; Johnson, Jeffrey R; Hull, Philip A; Montano, Mauricio; Sakane, Naoki; Pagans, Sara; Godin, Robert; Deeks, Steven G; Krogan, Nevan J; Greene, Warner C; Ott, Melanie

    2017-05-10

    Transcriptional latency of HIV is a last barrier to viral eradication. Chromatin-remodeling complexes and post-translational histone modifications likely play key roles in HIV-1 reactivation, but the underlying mechanisms are incompletely understood. We performed an RNAi-based screen of human lysine methyltransferases and identified the SET and MYND domain-containing protein 2 (SMYD2) as an enzyme that regulates HIV-1 latency. Knockdown of SMYD2 or its pharmacological inhibition reactivated latent HIV-1 in T cell lines and in primary CD4(+) T cells. SMYD2 associated with latent HIV-1 promoter chromatin, which was enriched in monomethylated lysine 20 at histone H4 (H4K20me1), a mark lost in cells lacking SMYD2. Further, we find that lethal 3 malignant brain tumor 1 (L3MBTL1), a reader protein with chromatin-compacting properties that recognizes H4K20me1, was recruited to the latent HIV-1 promoter in a SMYD2-dependent manner. We propose that a SMYD2-H4K20me1-L3MBTL1 axis contributes to HIV-1 latency and can be targeted with small-molecule SMYD2 inhibitors. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Epigenetic regulation of HIV-1 latency by cytosine methylation.

    Directory of Open Access Journals (Sweden)

    Steven E Kauder

    2009-06-01

    Full Text Available Human immunodeficiency virus type 1 (HIV-1 persists in a latent state within resting CD4+ T cells of infected persons treated with highly active antiretroviral therapy (HAART. This reservoir must be eliminated for the clearance of infection. Using a cDNA library screen, we have identified methyl-CpG binding domain protein 2 (MBD2 as a regulator of HIV-1 latency. Two CpG islands flank the HIV-1 transcription start site and are methylated in latently infected Jurkat cells and primary CD4+ T cells. MBD2 and histone deacetylase 2 (HDAC2 are found at one of these CpG islands during latency. Inhibition of cytosine methylation with 5-aza-2'deoxycytidine (aza-CdR abrogates recruitment of MBD2 and HDAC2. Furthermore, aza-CdR potently synergizes with the NF-kappaB activators prostratin or TNF-alpha to reactivate latent HIV-1. These observations confirm that cytosine methylation and MBD2 are epigenetic regulators of HIV-1 latency. Clearance of HIV-1 from infected persons may be enhanced by inclusion of DNA methylation inhibitors, such as aza-CdR, and NF-kappaB activators into current antiviral therapies.

  20. Absolute quantitation of protein posttranslational modification isoform.

    Science.gov (United States)

    Yang, Zhu; Li, Ning

    2015-01-01

    Mass spectrometry has been widely applied in characterization and quantification of proteins from complex biological samples. Because the numbers of absolute amounts of proteins are needed in construction of mathematical models for molecular systems of various biological phenotypes and phenomena, a number of quantitative proteomic methods have been adopted to measure absolute quantities of proteins using mass spectrometry. The liquid chromatography-tandem mass spectrometry (LC-MS/MS) coupled with internal peptide standards, i.e., the stable isotope-coded peptide dilution series, which was originated from the field of analytical chemistry, becomes a widely applied method in absolute quantitative proteomics research. This approach provides more and more absolute protein quantitation results of high confidence. As quantitative study of posttranslational modification (PTM) that modulates the biological activity of proteins is crucial for biological science and each isoform may contribute a unique biological function, degradation, and/or subcellular location, the absolute quantitation of protein PTM isoforms has become more relevant to its biological significance. In order to obtain the absolute cellular amount of a PTM isoform of a protein accurately, impacts of protein fractionation, protein enrichment, and proteolytic digestion yield should be taken into consideration and those effects before differentially stable isotope-coded PTM peptide standards are spiked into sample peptides have to be corrected. Assisted with stable isotope-labeled peptide standards, the absolute quantitation of isoforms of posttranslationally modified protein (AQUIP) method takes all these factors into account and determines the absolute amount of a protein PTM isoform from the absolute amount of the protein of interest and the PTM occupancy at the site of the protein. The absolute amount of the protein of interest is inferred by quantifying both the absolute amounts of a few PTM

  1. A Simulation Base Investigation of High Latency Space Systems Operations

    Science.gov (United States)

    Li, Zu Qun; Crues, Edwin Z.; Bielski, Paul; Moore, Michael

    2017-01-01

    NASA's human space program has developed considerable experience with near Earth space operations. Although NASA has experience with deep space robotic missions, NASA has little substantive experience with human deep space operations. Even in the Apollo program, the missions lasted only a few weeks and the communication latencies were on the order of seconds. Human missions beyond the relatively close confines of the Earth-Moon system will involve missions with durations measured in months and communications latencies measured in minutes. To minimize crew risk and to maximize mission success, NASA needs to develop a better understanding of the implications of these types of mission durations and communication latencies on vehicle design, mission design and flight controller interaction with the crew. To begin to address these needs, NASA performed a study using a physics-based subsystem simulation to investigate the interactions between spacecraft crew and a ground-based mission control center for vehicle subsystem operations across long communication delays. The simulation, built with a subsystem modeling tool developed at NASA's Johnson Space Center, models the life support system of a Mars transit vehicle. The simulation contains models of the cabin atmosphere and pressure control system, electrical power system, drinking and waste water systems, internal and external thermal control systems, and crew metabolic functions. The simulation has three interfaces: 1) a real-time crew interface that can be use to monitor and control the vehicle subsystems; 2) a mission control center interface with data transport delays up to 15 minutes each way; 3) a real-time simulation test conductor interface that can be use to insert subsystem malfunctions and observe the interactions between the crew, ground, and simulated vehicle. The study was conducted at the 21st NASA Extreme Environment Mission Operations (NEEMO) mission between July 18th and Aug 3rd of year 2016. The NEEMO

  2. Collecting and Using Low Latency Data at Berkeley Seismological Laboratory

    Science.gov (United States)

    Houlié, N.; Allen, R.; Hellweg, P.; Dreger, D.; Neuhauser, D.; Romanowicz, B.

    2008-12-01

    Northern California and the San Francisco Bay Area are among the US regions that combine high earthquake hazard and high population density. To rapidly and reliably monitor tectonic movement and develop an understanding of fault dynamics, measurements must cover a range of scales in time (0.1 s to years), space (mms to 100s of km) and displacement (microns to 10s of m). With these goals in mind, Berkeley Seismological Laboratory (BSL) continuously collects a wide variety of data at low latencies from seismic through geodetic, strain and electromagnetic instrumentation with sampling rates spanning 0.001 sps to 500 sps. Data from broadband seismometers and accelerometers, generally with latencies of less than 10 s, contribute to real time earthquake monitoring in Northern California including rapid assessments of source (moment tensor and finite fault) and shaking (ShakeMap). The BSL is also currently operating a real time system in test mode, using these data for earthquake early warning (ElarmS). Data from these instruments are also used for research on earthquake sources and scaling, fault-related tremor and studies of local, regional and global velocity structure. Low latency GPS data can complement seismic data, contributing robust real time continuous information especially for large earthquakes, and can potentially contribute to early warning. GPS-derived static deformation gives an independent estimate of fault orientation and dimensions, scalar seismic moment and magnitude. It also can extend the upper limits of a strong motion network to include the displacements of tens of meters expected in large and great earthquakes, and in the near field is less likely to be clipped during large movements. In an active tectonic context such as Northern California, low latency is important for data transmission, but also for reliability. At the BSL we are committed to using telemetry that is as robust as possible and often have more than one telemetry path to ensure

  3. Acceptable differences in sensory and motor latencies between the median and ulnar nerves.

    Science.gov (United States)

    Grossart, Elizabeth A; Prahlow, Nathan D; Buschbacher, Ralph M

    2006-01-01

    The median and ulnar nerves are often studied during the same electrodiagnostic examination. The sensory and motor latencies of these nerves have been compared to detect a common electrodiagnostic entity: median neuropathy at the wrist. However, this comparison could also be used to diagnose less common ulnar pathology. For this reason, it is important to establish normal values for comparing median and ulnar sensory and motor latencies. Previous research deriving these differences in latency has had some limitations. The purpose of this study was to derive an improved normative database for the acceptable differences in latency between the median and ulnar sensory and motor nerves of the same limb. Median and ulnar sensory and motor latencies were obtained from 219 and 238 asymptomatic risk-factor-free subjects, respectively. An analysis of variance was performed to determine whether physical characteristics, specifically age, race, gender, height, or body mass index (as an indicator of obesity), correlated with differences in latency. Differences in sensory latencies were unaffected by physical characteristics. The upper limit of normal difference between median and ulnar (median longer than ulnar) onset latency was 0.5 ms (97th percentile), whereas the peak latency value was 0.4 ms (97th percentile). The upper limit of normal difference between ulnar-versus-median (ulnar longer than median) onset latency was 0.3 ms (97th percentile), whereas the peak-latency value was 0.5 ms (97th percentile). The mean difference in motor latencies correlated with age, with older subjects having a greater variability. In subjects aged 50 and over, the mean difference in median-versus-ulnar latency was 0.9 ms +/- 0.4 ms. The upper limit of normal difference (median longer than ulnar) was 1.7 ms (97th percentile). The upper limit of normal ulnar motor latency is attained if the ulnar latency comes within 0.3 ms of the median latency. In individuals less than 50 years of age, the

  4. Test Operations Procedure (TOP) 02-2-546 Teleoperated Unmanned Ground Vehicle (UGV) Latency Measurements

    Science.gov (United States)

    2017-01-11

    A. Approved for public release; distribution is unlimited. 13. SUPPLEMENTARY NOTES Defense Technical Information Center (DTIC), AD No.: 14. ABSTRACT...discrete system components or measurements of latency in autonomous systems. 15. SUBJECT TERMS Unmanned Ground Vehicles, Basic Video Latency, End -to... End System Latency, Command-to-Action Latency 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT SAR 18. NUMBER OF PAGES 23 19a

  5. Latency of auditory evoked potential monitoring the effects of general anesthetics on nerve fibers and synapses

    OpenAIRE

    Bowan Huang; Feixue Liang; Lei Zhong; Minlin Lin; Juan Yang; Linqing Yan; Jinfan Xiao; Zhongju Xiao

    2015-01-01

    Auditory evoked potential (AEP) is an effective index for the effects of general anesthetics. However, it’s unknown if AEP can differentiate the effects of general anesthetics on nerve fibers and synapses. Presently, we investigated AEP latency and amplitude changes to different acoustic intensities during pentobarbital anesthesia. Latency more regularly changed than amplitude during anesthesia. AEP Latency monotonically decreased with acoustic intensity increase (i.e., latency-intensity curv...

  6. The Simplicity Argument and Absolute Morality

    Science.gov (United States)

    Mijuskovic, Ben

    1975-01-01

    In this paper the author has maintained that there is a similarity of thought to be found in the writings of Cudworth, Emerson, and Husserl in his investigation of an absolute system of morality. (Author/RK)

  7. The Simplicity Argument and Absolute Morality

    Science.gov (United States)

    Mijuskovic, Ben

    1975-01-01

    In this paper the author has maintained that there is a similarity of thought to be found in the writings of Cudworth, Emerson, and Husserl in his investigation of an absolute system of morality. (Author/RK)

  8. Magnifying absolute instruments for optically homogeneous regions

    CERN Document Server

    Tyc, Tomas

    2011-01-01

    We propose a class of magnifying absolute optical instruments with a positive isotropic refractive index. They create magnified stigmatic images, either virtual or real, of optically homogeneous three-dimensional spatial regions within geometrical optics.

  9. The risks of absolute medical confidentiality.

    Science.gov (United States)

    Crook, M A

    2013-03-01

    Some ethicists argue that patient confidentiality is absolute and thus should never be broken. I examine these arguments that when critically scrutinised, become porous. I will explore the concept of patient confidentiality and argue that although, this is a very important medical and bioethical issue, this needs to be wisely delivered to reduce third party harm or even detriment to the patient. The argument for absolute confidentiality is particularly weak when it comes to genetic information and inherited disease.

  10. Voluntary reaction time and long-latency reflex modulation.

    Science.gov (United States)

    Forgaard, Christopher J; Franks, Ian M; Maslovat, Dana; Chin, Laurence; Chua, Romeo

    2015-12-01

    Stretching a muscle of the upper limb elicits short (M1) and long-latency (M2) reflexes. When the participant is instructed to actively compensate for a perturbation, M1 is usually unaffected and M2 increases in size and is followed by the voluntary response. It remains unclear if the observed increase in M2 is due to instruction-dependent gain modulation of the contributing reflex mechanism(s) or results from voluntary response superposition. The difficulty in delineating between these alternatives is due to the overlap between the voluntary response and the end of M2. The present study manipulated response accuracy and complexity to delay onset of the voluntary response and observed the corresponding influence on electromyographic activity during the M2 period. In all active conditions, M2 was larger compared with a passive condition where participants did not respond to the perturbation; moreover, these changes in M2 began early in the appearance of the response (∼ 50 ms), too early to be accounted for by voluntary overlap. Voluntary response latency influenced the latter portion of M2, with the largest activity seen when accuracy of limb position was not specified. However, when participants aimed for targets of different sizes or performed movements of various complexities, reaction time differences did not influence M2 period activity, suggesting voluntary activity was sufficiently delayed. Collectively, our results show that while a perturbation applied to the upper limbs can trigger a voluntary response at short latency (reflex gain modulation remains an important contributor to EMG changes during the M2 period. Copyright © 2015 the American Physiological Society.

  11. CTCF prevents the epigenetic drift of EBV latency promoter Qp.

    Directory of Open Access Journals (Sweden)

    Italo Tempera

    Full Text Available The establishment and maintenance of Epstein-Barr Virus (EBV latent infection requires distinct viral gene expression programs. These gene expression programs, termed latency types, are determined largely by promoter selection, and controlled through the interplay between cell-type specific transcription factors, chromatin structure, and epigenetic modifications. We used a genome-wide chromatin-immunoprecipitation (ChIP assay to identify epigenetic modifications that correlate with different latency types. We found that the chromatin insulator protein CTCF binds at several key regulatory nodes in the EBV genome and may compartmentalize epigenetic modifications across the viral genome. Highly enriched CTCF binding sites were identified at the promoter regions upstream of Cp, Wp, EBERs, and Qp. Since Qp is essential for long-term maintenance of viral genomes in type I latency and epithelial cell infections, we focused on the role of CTCF in regulating Qp. Purified CTCF bound approximately 40 bp upstream of the EBNA1 binding sites located at +10 bp relative to the transcriptional initiation site at Qp. Mutagenesis of the CTCF binding site in EBV bacmids resulted in a decrease in the recovery of stable hygromycin-resistant episomes in 293 cells. EBV lacking the Qp CTCF site showed a decrease in Qp transcription initiation and a corresponding increase in Cp and Fp promoter utilization at 8 weeks post-transfection. However, by 16 weeks post-transfection, bacmids lacking CTCF sites had no detectable Qp transcription and showed high levels of histone H3 K9 methylation and CpG DNA methylation at the Qp initiation site. These findings provide direct genetic evidence that CTCF functions as a chromatin insulator that prevents the promiscuous transcription of surrounding genes and blocks the epigenetic silencing of an essential promoter, Qp, during EBV latent infection.

  12. CTCF prevents the epigenetic drift of EBV latency promoter Qp.

    Science.gov (United States)

    Tempera, Italo; Wiedmer, Andreas; Dheekollu, Jayaraju; Lieberman, Paul M

    2010-08-12

    The establishment and maintenance of Epstein-Barr Virus (EBV) latent infection requires distinct viral gene expression programs. These gene expression programs, termed latency types, are determined largely by promoter selection, and controlled through the interplay between cell-type specific transcription factors, chromatin structure, and epigenetic modifications. We used a genome-wide chromatin-immunoprecipitation (ChIP) assay to identify epigenetic modifications that correlate with different latency types. We found that the chromatin insulator protein CTCF binds at several key regulatory nodes in the EBV genome and may compartmentalize epigenetic modifications across the viral genome. Highly enriched CTCF binding sites were identified at the promoter regions upstream of Cp, Wp, EBERs, and Qp. Since Qp is essential for long-term maintenance of viral genomes in type I latency and epithelial cell infections, we focused on the role of CTCF in regulating Qp. Purified CTCF bound approximately 40 bp upstream of the EBNA1 binding sites located at +10 bp relative to the transcriptional initiation site at Qp. Mutagenesis of the CTCF binding site in EBV bacmids resulted in a decrease in the recovery of stable hygromycin-resistant episomes in 293 cells. EBV lacking the Qp CTCF site showed a decrease in Qp transcription initiation and a corresponding increase in Cp and Fp promoter utilization at 8 weeks post-transfection. However, by 16 weeks post-transfection, bacmids lacking CTCF sites had no detectable Qp transcription and showed high levels of histone H3 K9 methylation and CpG DNA methylation at the Qp initiation site. These findings provide direct genetic evidence that CTCF functions as a chromatin insulator that prevents the promiscuous transcription of surrounding genes and blocks the epigenetic silencing of an essential promoter, Qp, during EBV latent infection.

  13. Alphaherpesvirus Latency: A Dynamic State of Transcription and Reactivation.

    Science.gov (United States)

    Bloom, David C

    2016-01-01

    Alphaherpesviruses infect a variety of species from sea turtles to man and can cause significant disease in mammals including humans and livestock. These viruses are characterized by a lytic and latent state in nerve ganglia, with the ability to establish a lifelong latent infection that is interrupted by periodic reactivation. Previously, it was accepted that latency was a dominant state and that only during relatively infrequent reactivation episodes did latent genomes within ganglia become transcriptionally active. Here, we review recent data, focusing mainly on Herpes Simplex Virus type 1 which indicate that the latent state is more dynamic than recently appreciated.

  14. On determining absolute entropy without quantum theory or the third law of thermodynamics

    Science.gov (United States)

    Steane, Andrew M.

    2016-04-01

    We employ classical thermodynamics to gain information about absolute entropy, without recourse to statistical methods, quantum mechanics or the third law of thermodynamics. The Gibbs-Duhem equation yields various simple methods to determine the absolute entropy of a fluid. We also study the entropy of an ideal gas and the ionization of a plasma in thermal equilibrium. A single measurement of the degree of ionization can be used to determine an unknown constant in the entropy equation, and thus determine the absolute entropy of a gas. It follows from all these examples that the value of entropy at absolute zero temperature does not need to be assigned by postulate, but can be deduced empirically.

  15. Electron cyclotron emission measurements on JET: Michelson interferometer, new absolute calibration, and determination of electron temperature

    NARCIS (Netherlands)

    Schmuck, S.; Fessey, J.; Gerbaud, T.; Alper, B.; Beurskens, M. N. A.; de la Luna, E.; Sirinelli, A.; Zerbini, M.

    2012-01-01

    At the fusion experiment JET, a Michelson interferometer is used to measure the spectrum of the electron cyclotron emission in the spectral range 70-500 GHz. The interferometer is absolutely calibrated using the hot/cold technique and, in consequence, the spatial profile of the plasma electron tempe

  16. A global algorithm for estimating Absolute Salinity

    Directory of Open Access Journals (Sweden)

    T. J. McDougall

    2012-12-01

    Full Text Available The International Thermodynamic Equation of Seawater – 2010 has defined the thermodynamic properties of seawater in terms of a new salinity variable, Absolute Salinity, which takes into account the spatial variation of the composition of seawater. Absolute Salinity more accurately reflects the effects of the dissolved material in seawater on the thermodynamic properties (particularly density than does Practical Salinity.

    When a seawater sample has standard composition (i.e. the ratios of the constituents of sea salt are the same as those of surface water of the North Atlantic, Practical Salinity can be used to accurately evaluate the thermodynamic properties of seawater. When seawater is not of standard composition, Practical Salinity alone is not sufficient and the Absolute Salinity Anomaly needs to be estimated; this anomaly is as large as 0.025 g kg−1 in the northernmost North Pacific. Here we provide an algorithm for estimating Absolute Salinity Anomaly for any location (x, y, p in the world ocean.

    To develop this algorithm, we used the Absolute Salinity Anomaly that is found by comparing the density calculated from Practical Salinity to the density measured in the laboratory. These estimates of Absolute Salinity Anomaly however are limited to the number of available observations (namely 811. In order to provide a practical method that can be used at any location in the world ocean, we take advantage of approximate relationships between Absolute Salinity Anomaly and silicate concentrations (which are available globally.

  17. Bounds on Stability and Latency in Wireless Communication

    CERN Document Server

    Cholvi, Vicent

    2010-01-01

    In this paper, we study stability and latency of routing in wireless networks where it is assumed that no collision will occur. Our approach is inspired by the adversarial queuing theory, which is amended in order to model wireless communication. More precisely, there is an adversary that specifies transmission rates of wireless links and injects data in such a way that an average number of data injected in a single round and routed through a single wireless link is at most $r$, for a given $r\\in (0,1)$. We also assume that the additional "burst" of data injected during any time interval and scheduled via a single link is bounded by a given parameter $b$. Under this scenario, we show that the nodes following so called {\\em work-conserving} scheduling policies, not necessarily the same, are guaranteed stability (i.e., bounded queues) and reasonably small data latency (i.e., bounded time on data delivery), for injection rates $r<1/d$, where $d$ is the maximum length of a routing path. Furthermore, we also sh...

  18. Jasminum flexile flower absolute from India--a detailed comparison with three other jasmine absolutes.

    Science.gov (United States)

    Braun, Norbert A; Kohlenberg, Birgit; Sim, Sherina; Meier, Manfred; Hammerschmidt, Franz-Josef

    2009-09-01

    Jasminum flexile flower absolute from the south of India and the corresponding vacuum headspace (VHS) sample of the absolute were analyzed using GC and GC-MS. Three other commercially available Indian jasmine absolutes from the species: J. sambac, J. officinale subsp. grandiflorum, and J. auriculatum and the respective VHS samples were used for comparison purposes. One hundred and twenty-one compounds were characterized in J. flexile flower absolute, with methyl linolate, benzyl salicylate, benzyl benzoate, (2E,6E)-farnesol, and benzyl acetate as the main constituents. A detailed olfactory evaluation was also performed.

  19. Quantum theory allows for absolute maximal contextuality

    Science.gov (United States)

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

    2015-12-01

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

  20. Absolute photoacoustic thermometry in deep tissue.

    Science.gov (United States)

    Yao, Junjie; Ke, Haixin; Tai, Stephen; Zhou, Yong; Wang, Lihong V

    2013-12-15

    Photoacoustic thermography is a promising tool for temperature measurement in deep tissue. Here we propose an absolute temperature measurement method based on the dual temperature dependences of the Grüneisen parameter and the speed of sound in tissue. By taking ratiometric measurements at two adjacent temperatures, we can eliminate the factors that are temperature irrelevant but difficult to correct for in deep tissue. To validate our method, absolute temperatures of blood-filled tubes embedded ~9 mm deep in chicken tissue were measured in a biologically relevant range from 28°C to 46°C. The temperature measurement accuracy was ~0.6°C. The results suggest that our method can be potentially used for absolute temperature monitoring in deep tissue during thermotherapy.

  1. Effects of ankle joint cooling on peroneal short latency response.

    Science.gov (United States)

    Hopkins, J Ty; Hunter, Iain; McLoda, Todd

    2006-01-01

    While cryotherapy has direct physiological effects on contractile tissues, the extent to which joint cooling affects the neuromuscular system is not well understood. The purpose of the study was to detect changes in ankle dynamic restraint (peroneal short latency response and muscle activity amplitude) during inversion perturbation following ankle joint cryotherapy. A 2x3 factorial design was used to compare reaction time and EMG amplitude data of treatment conditions (cryotherapy and control) across time (pre-treatment, post-treatment, and 30 min post-treatment). Thirteen healthy volunteers (age 23 ± 4 yrs, ht 1.76 ± 0.09 m, mass 78.8 ± 16.6 kg), with no history of lower extremity joint injury participated in this study. Surface EMG was collected from the peroneus longus (PL) of the dominant leg during an ankle inversion perturbation triggered while walking. Subjects walked the length of a 6.1 m runway 30 times. A trap door mechanism, inducing inversion perturbation, was released at heel contact during six randomly selected trials for each leg. Following baseline measurements, a 1.5 L bag of crushed ice was applied to the lateral ankle of subjects in the treatment group with an elastic wrap. A bag similar in weight and consistency was applied to the lateral ankle of subjects in the control group. A repeated measures ANOVA was used to compare treatment conditions across time (p 0.05) for PL reaction time. Average RMS EMG, normalized to an isometric reference position, increased in the cryotherapy group at the 30 min post-treatment interval relative to the control group (p movement is unknown.Short latency response should be measured during functional movement instead of during stance to take into consideration alterations in motor drive.Joint cooling has no effect on peroneal short latency response, and joint cooling may result in increased short term peroneal activation.Joint cooling has no effect on the peroneus longus as a dynamic stabilizer during walking.

  2. Absolute Asymmetric Synthesis Using A Cocrystal Approach

    Institute of Scientific and Technical Information of China (English)

    H.Koshima

    2007-01-01

    1 Results Absolute asymmetric synthesis by means of solid-state reaction of chiral crystals self-assembled from achiral molecules is an attractive and promising methodology for asymmetric synthesis because it is not necessary to employ any external chiral source like a chiral catalyst.In order to design reliably absolute asymmetric syntheses in the solid state,it is inevitable to prepare and predict the formation of chiral crystals from achiral compounds.We have prepared a number of chiral cocrystals co...

  3. Absolute-Magnitude Distributions of Supernovae

    CERN Document Server

    Richardson, Dean; Wright, John; Maddox, Larry

    2014-01-01

    The absolute-magnitude distributions of seven supernova types are presented. The data used here were primarily taken from the Asiago Supernova Catalogue, but were supplemented with additional data. We accounted for both foreground and host-galaxy extinction. A bootstrap method is used to correct the samples for Malmquist bias. Separately, we generate volume-limited samples, restricted to events within 100 Mpc. We find that the superluminous events (M_B -15) make up about 3%. The normal Ia distribution was the brightest with a mean absolute blue magnitude of -19.25. The IIP distribution was the dimmest at -16.75.

  4. Absolute Stability Limit for Relativistic Charged Spheres

    CERN Document Server

    Giuliani, Alessandro

    2007-01-01

    We find an exact solution for the stability limit of relativistic charged spheres for the case of constant gravitational mass density and constant charge density. We argue that this provides an absolute stability limit for any relativistic charged sphere in which the gravitational mass density decreases with radius and the charge density increases with radius. We then provide a cruder absolute stability limit that applies to any charged sphere with a spherically symmetric mass and charge distribution. We give numerical results for all cases. In addition, we discuss the example of a neutral sphere surrounded by a thin, charged shell.

  5. Minimization of Handoff Latency by Distance Measurement Method

    Directory of Open Access Journals (Sweden)

    Debabrata Sarddar

    2011-03-01

    Full Text Available Now a day, IEEE 802.11 based wireless local area networks (WLAN have been widely deployed for business and personal applications. The main issue regarding wireless network technology is handoff or hand over management. Quality of service (QoS demanding applications like Voice over IP (VoIP and multimedia require seamless handover. But handoff delay (time required to perform hand off provides a serious barrier for such services to be made available to mobile platforms. Throughout the last few years so many researches had been done to reduce the hand off delay. Here we propose a new scanning method in which we determine the distance of nearest access points from the mobile node to bypass the main processes involved in increasing Medium Access Control (MAC layer handoff latency.

  6. Neural network connectivity and response latency modelled by stochastic processes

    DEFF Research Database (Denmark)

    Tamborrino, Massimiliano

    is connected to thousands of other neurons. The rst question is: how to model neural networks through stochastic processes? A multivariate Ornstein-Uhlenbeck process, obtained as a diffusion approximation of a jump process, is the proposed answer. Obviously, dependencies between neurons imply dependencies...... between their spike times. Therefore, the second question is: how to detect neural network connectivity from simultaneously recorded spike trains? Answering this question corresponds to investigate the joint distribution of sequences of rst passage times. A non-parametric method based on copulas...... generation of pikes. When a stimulus is applied to the network, the spontaneous rings may prevail and hamper detection of the effects of the stimulus. Therefore, the spontaneous rings cannot be ignored and the response latency has to be detected on top of a background signal. Everything becomes more dicult...

  7. Short latency vestibular evoked potentials in the chicken embryo

    Science.gov (United States)

    Jones, S. M.; Jones, T. A.

    1996-01-01

    Electrophysiological responses to pulsed linear acceleration stimuli were recorded in chicken embryos incubated for 19 or 20 days (E19/E20). Responses occurred within the first 16 ms following the stimulus onset. The evoked potentials disappeared following bilateral labyrinthectomy, but persisted following cochlear destruction alone, thus demonstrating that the responses were vestibular. Approximately 8 to 10 response peaks could be identified. The first 4 positive and corresponding negative components (early peaks with latencies embryos was -15.9dBre 1.0 g/ms, which was significantly higher (P embryos and 2-week-old animals, but amplitude/intensity functions for embryos were significantly shallower than those for 2-week-old birds (P embryo and, as such, the method shows promise as an investigative tool. The results of the present study form the definitive basis for using vestibular evoked potentials in the detailed study of avian vestibular ontogeny and factors that may influence it.

  8. Cortical modulation of short-latency TMS-evoked potentials

    Directory of Open Access Journals (Sweden)

    Domenica eVeniero

    2013-01-01

    Full Text Available Transcranial magnetic stimulation - electroencephalogram (TMS-EEG co-registration offers the opportunity to test reactivity of brain areas across distinct conditions through TMS-evoked potentials (TEPs. Several TEPs have been described, their functional meaning being largely unknown. In particular, short-latency potentials peaking at 5 (P5 and 8 (N8 ms after the TMS pulse have been recently described, but because of their huge amplitude, the problem of whether their origin is cortical or not has been opened. To gain information about these components, we employed a protocol that modulates primary motor cortex excitability (MI through an exclusively cortical phenomena: low frequency stimulation of premotor area (PMC. TMS was applied simultaneously with EEG recording from 70 electrodes. Amplitude of TEPs evoked by 200 single-pulses TMS delivered over MI at 110% of resting motor threshold was measured before and after applying 900 TMS conditioning stimuli to left premotor cortex with 1 Hz repetition rate. Single subject analyses showed reduction in TEPs amplitude after PMC conditioning in a sample of participants and increase in TEPs amplitude in two subjects. No effects were found on corticospinal excitability as recorded by motor evoked potentials (MEPs. Furthermore, correlation analysis showed an inverse relation between the effects of the conditioning protocol on P5-N8 complex amplitude and MEPs amplitude. Because the effects of the used protocol have been ascribed to a cortical interaction between premotor area and MI, we suggest that despite the sign of P5-N8 amplitude modulation is not consistent across participant, this modulation could indicate, at least in part, their cortical origin. We conclude that with an accurate experimental procedure early-latency components can be used to evaluate the reactivity of the stimulated cortex.

  9. Novel technology for reducing wavefront image processing latency

    Science.gov (United States)

    Barr, David; Schwartz, Noah; Vick, Andy; Coughlan, John; Halsall, Rob; Basden, Alastair; Dipper, Nigel

    2016-07-01

    Adaptive optics is essential for the successful operation of the future Extremely Large Telescopes (ELTs). At the heart of these AO system lies the real-time control which has become computationally challenging. A majority of the previous efforts has been aimed at reducing the wavefront reconstruction latency by using many-core hardware accelerators such as Xeon Phis and GPUs. These modern hardware solutions offer a large numbers of cores combined with high memory bandwidths but have restrictive input/output (I/O). The lack of efficient I/O capability makes the data handling very inefficient and adds both to the overall latency and jitter. For example a single wavefront sensor for an ELT scale adaptive optics system can produce hundreds of millions of pixels per second that need to be processed. Passing all this data through a CPU and into GPUs or Xeon Phis, even by reducing memory copies by using systems such as GPUDirect, is highly inefficient. The Mellanox TILE series is a novel technology offering a high number of cores and multiple 10 Gbps Ethernet ports. We present results of the TILE-Gx36 as a front-end wavefront sensor processing unit. In doing so we are able to greatly reduce the amount of data needed to be transferred to the wavefront reconstruction hardware. We show that the performance of the Mellanox TILE-GX36 is in-line with typical requirements, in terms of mean calculation time and acceptable jitter, for E-ELT first-light instruments and that the Mellanox TILE series is a serious contender for all E-ELT instruments.

  10. Long Latency Auditory Evoked Potential in Term and Premature Infants

    Directory of Open Access Journals (Sweden)

    Didoné, Dayane Domeneghini

    2014-01-01

    Full Text Available Introduction The research in long latency auditory evokes potentials (LLAEP in newborns is recent because of the cortical structure maturation, but studies note that these potentials may be evidenced at this age and could be considered as indicators of cognitive development. Purpose To research the exogenous potentials in term and premature infants during their first month of life. Materials and Methods The sample consisted of 25 newborns, 15 term and 10 premature infants. The infants with gestational age under 37 weeks were considered premature. To evaluate the cortical potentials, the infants remained in natural sleep. The LLAEPs were researched binaurally, through insertion earphones, with frequent /ba/ and rare /ga/ speech stimuli in the intensity of 80 dB HL (decibel hearing level. The frequent stimuli presented a total of 80% of the presentations, and the rare, 20%. The data were statistically analyzed. Results The average gestational age of the term infants was 38.9 weeks (± 1.3 and for the premature group, 33.9 weeks (± 1.6. It was possible to observe only the potentials P1 and N1 in both groups, but there was no statistically significant difference for the latencies of the components P1 and N1 (p > 0.05 between the groups. Conclusion It was possible to observe the exogenous components P1 and N1 of the cortical potentials in both term and preterm newborns of no more than 1 month of age. However, there was no difference between the groups.

  11. Multifocal visual evoked potential latency analysis: predicting progression to multiple sclerosis.

    Science.gov (United States)

    Fraser, Clare; Klistorner, Alexander; Graham, Stuart; Garrick, Raymond; Billson, Francis; Grigg, John

    2006-06-01

    To monitor the difference in conversion rates to multiple sclerosis (MS) in 46 patients with optic neuritis between patients with multifocal visual evoked potential latency delay and those with normal latency. Prospective case series. Metropolitan neuro-ophthalmology clinic. Forty-six patients with optic neuritis who did not have a diagnosis of MS on enrollment in the study. Conversion to MS according to the McDonald criteria. Analysis revealed that only 22 subjects had multifocal visual evoked potential latency delay. Over 1 year, 36.4% of patients with optic neuritis with latency delays progressed clinically to MS compared with 0% of those with normal latencies (P = .03, chi2). This may indicate that multifocal visual evoked potential latency delay can assist in predicting progression to future MS.

  12. Stimulus Probability Effects in Absolute Identification

    Science.gov (United States)

    Kent, Christopher; Lamberts, Koen

    2016-01-01

    This study investigated the effect of stimulus presentation probability on accuracy and response times in an absolute identification task. Three schedules of presentation were used to investigate the interaction between presentation probability and stimulus position within the set. Data from individual participants indicated strong effects of…

  13. Time Function and Absolute Black Hole

    DEFF Research Database (Denmark)

    Javadi, Hossein; Forouzbakhsh, Farshid

    2006-01-01

    Einstein’s theory of gravity is not consistent with quantum mechanics, because general relativity cannot be quantized. [1] But without conversion of force and energy, it is impossible to find a grand unified theory. A very important result of CPH theory is time function that allows we give a new ...... description of absolute black hole and before the big bang....

  14. Teaching Absolute Value Inequalities to Mature Students

    Science.gov (United States)

    Sierpinska, Anna; Bobos, Georgeana; Pruncut, Andreea

    2011-01-01

    This paper gives an account of a teaching experiment on absolute value inequalities, whose aim was to identify characteristics of an approach that would realize the potential of the topic to develop theoretical thinking in students enrolled in prerequisite mathematics courses at a large, urban North American university. The potential is…

  15. Thin-film magnetoresistive absolute position detector

    NARCIS (Netherlands)

    Groenland, Johannes Petrus Jacobus

    1990-01-01

    The subject of this thesis is the investigation of a digital absolute posi- tion-detection system, which is based on a position-information carrier (i.e. a magnetic tape) with one single code track on the one hand, and an array of magnetoresistive sensors for the detection of the informatio

  16. Det demokratiske argument for absolut ytringsfrihed

    DEFF Research Database (Denmark)

    Lægaard, Sune

    2014-01-01

    Artiklen diskuterer den påstand, at absolut ytringsfrihed er en nødvendig forudsætning for demokratisk legitimitet med udgangspunkt i en rekonstruktion af et argument fremsat af Ronald Dworkin. Spørgsmålet er, hvorfor ytringsfrihed skulle være en forudsætning for demokratisk legitimitet, og hvorf...

  17. Magnetoresistive sensor for absolute position detection

    NARCIS (Netherlands)

    Groenland, J.P.J.

    1984-01-01

    A digital measurement principle for absolute position is decscribed. The position data is recorded serially into a single track of a hard-magnetic layer with the help of longitudinal saturation recording. Detection is possible by means of an array of sensor elements which can be made of a substrate.

  18. Generalized Norms Inequalities for Absolute Value Operators

    Directory of Open Access Journals (Sweden)

    Ilyas Ali

    2014-02-01

    Full Text Available In this article, we generalize some norms inequalities for sums, differences, and products of absolute value operators. Our results based on Minkowski type inequalities and generalized forms of the Cauchy-Schwarz inequality. Some other related inequalities are also discussed.

  19. New Techniques for Absolute Gravity Measurements.

    Science.gov (United States)

    1983-01-07

    Hammond, J.A. (1978) Bollettino Di Geofisica Teorica ed Applicata Vol. XX. 8. Hammond, J. A., and Iliff, R. L. (1979) The AFGL absolute gravity system...International Gravimetric Bureau, No. L:I-43. 7. Hammond. J.A. (1978) Bollettino Di Geofisica Teorica ed Applicata Vol. XX. 8. Hammond, J.A., and

  20. Det demokratiske argument for absolut ytringsfrihed

    DEFF Research Database (Denmark)

    Lægaard, Sune

    2014-01-01

    Artiklen diskuterer den påstand, at absolut ytringsfrihed er en nødvendig forudsætning for demokratisk legitimitet med udgangspunkt i en rekonstruktion af et argument fremsat af Ronald Dworkin. Spørgsmålet er, hvorfor ytringsfrihed skulle være en forudsætning for demokratisk legitimitet, og hvorfor...

  1. Stimulus Probability Effects in Absolute Identification

    Science.gov (United States)

    Kent, Christopher; Lamberts, Koen

    2016-01-01

    This study investigated the effect of stimulus presentation probability on accuracy and response times in an absolute identification task. Three schedules of presentation were used to investigate the interaction between presentation probability and stimulus position within the set. Data from individual participants indicated strong effects of…

  2. Integer-valued Lévy processes and low latency financial econometrics

    DEFF Research Database (Denmark)

    Barndorff-Nielsen, Ole; Pollard, David G.; Shephard, Neil

    Motivated by features of low latency data in financial econometrics we study in detail integervalued Lévy processes as the basis of price processes for high frequency econometrics. We propose using models built out of the difference of two subordinators. We apply these models in practice to low...... latency data for a variety of different types of futures contracts.futures markets, high frequency econometrics, low latency data, negative binomial, Skellam, tempered stable...

  3. Key factors in web latency savings in an experimental prefetching system

    OpenAIRE

    De La Ossa Perez, Bernardo Antonio; Sahuquillo Borrás, Julio; Pont Sanjuan, Ana; Gil Salinas, José Antonio

    2012-01-01

    Although Internet service providers and communications companies are continuously offering higher and higher bandwidths, users still complain about the high latency they perceive when downloading pages from the web. Therefore, latency can be considered as the main web performance metric from the user's point of view. Many studies have demonstrated that web prefetching can be an interesting technique to reduce such latency at the expense of slightly increasing the network traffic. In this cont...

  4. Absolute Radiation Thermometry in the NIR

    Science.gov (United States)

    Bünger, L.; Taubert, R. D.; Gutschwager, B.; Anhalt, K.; Briaudeau, S.; Sadli, M.

    2017-04-01

    A near infrared (NIR) radiation thermometer (RT) for temperature measurements in the range from 773 K up to 1235 K was characterized and calibrated in terms of the "Mise en Pratique for the definition of the Kelvin" (MeP-K) by measuring its absolute spectral radiance responsivity. Using Planck's law of thermal radiation allows the direct measurement of the thermodynamic temperature independently of any ITS-90 fixed-point. To determine the absolute spectral radiance responsivity of the radiation thermometer in the NIR spectral region, an existing PTB monochromator-based calibration setup was upgraded with a supercontinuum laser system (0.45 μm to 2.4 μm) resulting in a significantly improved signal-to-noise ratio. The RT was characterized with respect to its nonlinearity, size-of-source effect, distance effect, and the consistency of its individual temperature measuring ranges. To further improve the calibration setup, a new tool for the aperture alignment and distance measurement was developed. Furthermore, the diffraction correction as well as the impedance correction of the current-to-voltage converter is considered. The calibration scheme and the corresponding uncertainty budget of the absolute spectral responsivity are presented. A relative standard uncertainty of 0.1 % (k=1) for the absolute spectral radiance responsivity was achieved. The absolute radiometric calibration was validated at four temperature values with respect to the ITS-90 via a variable temperature heatpipe blackbody (773 K ...1235 K) and at a gold fixed-point blackbody radiator (1337.33 K).

  5. Performance Comparison of Latency for RSC-RSC and RS-RSC Concatenated Codes

    Directory of Open Access Journals (Sweden)

    Manish Kumar

    2013-09-01

    Full Text Available In this paper, we compare the latency of serially concatenated convolutional codes. In particular, we compare RSC-RSC   concatenated codes using non-iterative concatenated Viterbi decoding to RS-RSC concatenated codes using concatenation of Viterbi & Berklelamp-Massey decoding. We have also used puncturing to obtain different code rates & analyzed the effect of code rate on latency. On the basis of simulations, it is shown that RSC-RSC code is better than RS-RSC codes for low latency applications. It is also shown that a trade-off is needed between BER & latency for concatenated codes.

  6. Interferon alpha induces establishment of alphaherpesvirus latency in sensory neurons in vitro.

    Directory of Open Access Journals (Sweden)

    Nick De Regge

    Full Text Available BACKGROUND: Several alphaherpesviruses, including herpes simplex virus 1 (HSV-1 and pseudorabies virus (PRV, establish lifelong latency in neurons of the trigeminal ganglion (TG. Although it is thought that efficient establishment of alphaherpesvirus latency is based on a subtle interplay between virus, neurons and the immune system, it is not clear which immune components are of major importance for the establishment of latency. METHODOLOGY/PRINCIPAL FINDINGS: Here, using an in vitro model that enables a natural route of infection, we show that interferon alpha (IFNalpha has the previously uncharacterized capacity to induce a quiescent HSV-1 and PRV infection in porcine TG neurons that shows strong similarity to in vivo latency. IFNalpha induced a stably suppressed HSV-1 and PRV infection in TG neurons in vitro. Subsequent treatment of neurons containing stably suppressed virus with forskolin resulted in reactivation of both viruses. HSV and PRV latency in vivo is often accompanied by the expression of latency associated transcripts (LATs. Infection of TG neurons with an HSV-1 mutant expressing LacZ under control of the LAT promoter showed activation of the LAT promoter and RT-PCR analysis confirmed that both HSV-1 and PRV express LATs during latency in vitro. CONCLUSIONS/SIGNIFICANCE: These data represent a unique in vitro model of alphaherpesvirus latency and indicate that IFNalpha may be a driving force in promoting efficient latency establishment.

  7. Bridging HIV-1 cellular latency and clinical long-term non-progressor: an interactomic view.

    Directory of Open Access Journals (Sweden)

    Jin Yang

    Full Text Available Development of an effective HIV management is enticed by the fact that long-term non-progressors (LTNP restrict viral replication spontaneously, but is hindered by HIV-1 latency. Given that the most overlapping characteristics found between HIV-1 LTNP and latency, detailed analysis of the difference would disclose the essentials of latency. In this study, microarray data from our previous study was combined with HIV-1 latency and LTNP data obtained from NCBI GEO database. Principal variance component analysis and hierarchical clustering verified the removal of batch effect across platform. The analysis revealed a total of 456 differential expressed genes with >2-fold change and B-statistic >0. Bayesian inference was used to reconstitute the transcriptional network of HIV-1 latency or LTNP, respectively. Gene regulation was reprogrammed under different disease condition. By network interference, KPNA2 and ATP5G3 were identified as the hubs in latency network which mediate nuclear export and RNA processing. These data offer comparative insights into HIV-1 latency, which will facilitate the understanding of the genetic basis of HIV-1 latency in vivo and serve as a clue for future treatment dealing with key targets in HIV-1 latency.

  8. Small Molecule Inhibitors of BAF; A Promising Family of Compounds in HIV-1 Latency Reversal

    Directory of Open Access Journals (Sweden)

    Mateusz Stoszko

    2016-01-01

    Full Text Available Persistence of latently infected cells in presence of Anti-Retroviral Therapy presents the main obstacle to HIV-1 eradication. Much effort is thus placed on identification of compounds capable of HIV-1 latency reversal in order to render infected cells susceptible to viral cytopathic effects and immune clearance. We identified the BAF chromatin remodeling complex as a key player required for maintenance of HIV-1 latency, highlighting its potential as a molecular target for inhibition in latency reversal. Here, we screened a recently identified panel of small molecule inhibitors of BAF (BAFi's for potential to activate latent HIV-1. Latency reversal was strongly induced by BAFi's Caffeic Acid Phenethyl Ester and Pyrimethamine, two molecules previously characterized for clinical application. BAFi's reversed HIV-1 latency in cell line based latency models, in two ex vivo infected primary cell models of latency, as well as in HIV-1 infected patient's CD4+ T cells, without inducing T cell proliferation or activation. BAFi-induced HIV-1 latency reversal was synergistically enhanced upon PKC pathway activation and HDAC-inhibition. Therefore BAFi's constitute a promising family of molecules for inclusion in therapeutic combinatorial HIV-1 latency reversal.

  9. Systematic analysis of human oncogenic viruses in colon cancer revealed EBV latency in lymphoid infiltrates.

    Science.gov (United States)

    Fiorina, Loretta; Ricotti, Mattia; Vanoli, Alessandro; Luinetti, Ombretta; Dallera, Elena; Riboni, Roberta; Paolucci, Stefania; Brugnatelli, Silvia; Paulli, Marco; Pedrazzoli, Paolo; Baldanti, Fausto; Perfetti, Vittorio

    2014-01-01

    Environmental factors may play a role in colon cancer. In this view, several studies investigated tumor samples for the presence of various viral DNA with conflicting results. We undertook a systematic DNA analysis of 44 consecutive, prospectively collected primary tumor samples by real time and qualitative PCR for viruses of known or potential oncogenic role in humans, including polyomavirus (JCV, BKV, Merkel cell polyomavirus), HPV, HTLV, HHV-8 and EBV. Negative controls consisted of surgical resection margins. No evidence of genomic DNA fragments from tested virus were detected, except for EBV, which was found in a significant portion of tumors (23/44, 52%). Real-time PCR showed that EBV DNA was present at a highly variable content (median 258 copies in 10(5) cells, range 15-4837). Presence of EBV DNA had a trend to be associated with high lymphocyte infiltration (p = 0.06, χ2 test), and in situ hybridization with EBER1-2 probes revealed latency in a fraction of these lymphoid cells, with just a few scattered plasma cells positive for BZLF-1, an immediate early protein expressed during lytic replication. LMP-1 expression was undetectable by immunohistochemistry. These results argue against a significant involvement of the tested oncogenic viruses in established colon cancer.

  10. From Hubble's NGSL to Absolute Fluxes

    Science.gov (United States)

    Heap, Sara R.; Lindler, Don

    2012-01-01

    Hubble's Next Generation Spectral Library (NGSL) consists of R-l000 spectra of 374 stars of assorted temperature, gravity, and metallicity. Each spectrum covers the wavelength range, 0.18-1.00 microns. The library can be viewed and/or downloaded from the website, http://archive.stsci.edu/prepds/stisngsll. Stars in the NGSL are now being used as absolute flux standards at ground-based observatories. However, the uncertainty in the absolute flux is about 2%, which does not meet the requirements of dark-energy surveys. We are therefore developing an observing procedure that should yield fluxes with uncertainties less than 1 % and will take part in an HST proposal to observe up to 15 stars using this new procedure.

  11. Absolute and relative dosimetry for ELIMED

    Science.gov (United States)

    Cirrone, G. A. P.; Cuttone, G.; Candiano, G.; Carpinelli, M.; Leonora, E.; Lo Presti, D.; Musumarra, A.; Pisciotta, P.; Raffaele, L.; Randazzo, N.; Romano, F.; Schillaci, F.; Scuderi, V.; Tramontana, A.; Cirio, R.; Marchetto, F.; Sacchi, R.; Giordanengo, S.; Monaco, V.

    2013-07-01

    The definition of detectors, methods and procedures for the absolute and relative dosimetry of laser-driven proton beams is a crucial step toward the clinical use of this new kind of beams. Hence, one of the ELIMED task, will be the definition of procedures aiming to obtain an absolute dose measure at the end of the transport beamline with an accuracy as close as possible to the one required for clinical applications (i.e. of the order of 5% or less). Relative dosimetry procedures must be established, as well: they are necessary in order to determine and verify the beam dose distributions and to monitor the beam fluence and the energetic spectra during irradiations. Radiochromic films, CR39, Faraday Cup, Secondary Emission Monitor (SEM) and transmission ionization chamber will be considered, designed and studied in order to perform a fully dosimetric characterization of the ELIMED proton beam.

  12. Learning in a unidimensional absolute identification task.

    Science.gov (United States)

    Rouder, Jeffrey N; Morey, Richard D; Cowan, Nelson; Pfaltz, Monique

    2004-10-01

    We tested whether there is long-term learning in the absolute identification of line lengths. Line lengths are unidimensional stimuli, and there is a common belief that learning of these stimuli quickly reaches a low-level asymptote of about seven items and progresses no more. We show that this is not the case. Our participants served in a 1.5-h session each day for over a week. Although they did not achieve perfect performance, they continued to improve day by day throughout the week and eventually learned to distinguish between 12 and 20 line lengths. These results are in contrast to common characterizations of learning in absolute identification tasks with unidimensional stimuli. We suggest that this learning reflects improvement in short-term processing.

  13. Asteroid absolute magnitudes and slope parameters

    Science.gov (United States)

    Tedesco, Edward F.

    1991-01-01

    A new listing of absolute magnitudes (H) and slope parameters (G) has been created and published in the Minor Planet Circulars; this same listing will appear in the 1992 Ephemerides of Minor Planets. Unlike previous listings, the values of the current list were derived from fits of data at the V band. All observations were reduced in the same fashion using, where appropriate, a single basis default value of 0.15 for the slope parameter. Distances and phase angles were computed for each observation. The data for 113 asteroids was of sufficiently high quality to permit derivation of their H and G. These improved absolute magnitudes and slope parameters will be used to deduce the most reliable bias-corrected asteroid size-frequency distribution yet made.

  14. Absolute zero and the conquest of cold

    CERN Document Server

    Shachtman, Tom

    2000-01-01

    In a sweeping yet marvelously concise history, Tom Shachtman ushers us into a world in which scientists tease apart the all-important secrets of cold. Readers take an extraordinary trip, starting in the 1600s with an alchemist's air conditioning of Westminster Abbey and scientists' creation of thermometers. Later, while entrepreneurs sold Walden Pond ice to tropical countries -- packed in "high-tech" sawdust -- researchers pursued absolute zero and interpreted their work as romantically as did adventurers to remote regions. Today, playing with ultracold temperatures is one of the hottest frontiers in physics, with scientists creating useful particles Einstein only dreamed of. Tom Shachtman shares a great scientific adventure story and its characters' rich lives in a book that has won a grant from the prestigious Alfred P. Sloan Foundation. Absolute Zero is for everyone who loves history and science history stories, who's eager to explore Nobel Prize-winning physics today, or who has ever sighed with pleasure ...

  15. An absolute measure for a key currency

    Science.gov (United States)

    Oya, Shunsuke; Aihara, Kazuyuki; Hirata, Yoshito

    It is generally considered that the US dollar and the euro are the key currencies in the world and in Europe, respectively. However, there is no absolute general measure for a key currency. Here, we investigate the 24-hour periodicity of foreign exchange markets using a recurrence plot, and define an absolute measure for a key currency based on the strength of the periodicity. Moreover, we analyze the time evolution of this measure. The results show that the credibility of the US dollar has not decreased significantly since the Lehman shock, when the Lehman Brothers bankrupted and influenced the economic markets, and has increased even relatively better than that of the euro and that of the Japanese yen.

  16. Absolute and relative dosimetry for ELIMED

    Energy Technology Data Exchange (ETDEWEB)

    Cirrone, G. A. P.; Schillaci, F.; Scuderi, V. [INFN, Laboratori Nazionali del Sud, Via Santa Sofia 62, Catania, Italy and Institute of Physics Czech Academy of Science, ELI-Beamlines project, Na Slovance 2, Prague (Czech Republic); Cuttone, G.; Candiano, G.; Musumarra, A.; Pisciotta, P.; Romano, F. [INFN, Laboratori Nazionali del Sud, Via Santa Sofia 62, Catania (Italy); Carpinelli, M. [INFN Sezione di Cagliari, c/o Dipartimento di Fisica, Università di Cagliari, Cagliari (Italy); Leonora, E.; Randazzo, N. [INFN-Sezione di Catania, Via Santa Sofia 64, Catania (Italy); Presti, D. Lo [INFN-Sezione di Catania, Via Santa Sofia 64, Catania, Italy and Università di Catania, Dipartimento di Fisica e Astronomia, Via S. Sofia 64, Catania (Italy); Raffaele, L. [INFN, Laboratori Nazionali del Sud, Via Santa Sofia 62, Catania, Italy and INFN-Sezione di Catania, Via Santa Sofia 64, Catania (Italy); Tramontana, A. [INFN, Laboratori Nazionali del Sud, Via Santa Sofia 62, Catania, Italy and Università di Catania, Dipartimento di Fisica e Astronomia, Via S. Sofia 64, Catania (Italy); Cirio, R.; Sacchi, R.; Monaco, V. [INFN, Sezione di Torino, Via P.Giuria, 1 10125 Torino, Italy and Università di Torino, Dipartimento di Fisica, Via P.Giuria, 1 10125 Torino (Italy); Marchetto, F.; Giordanengo, S. [INFN, Sezione di Torino, Via P.Giuria, 1 10125 Torino (Italy)

    2013-07-26

    The definition of detectors, methods and procedures for the absolute and relative dosimetry of laser-driven proton beams is a crucial step toward the clinical use of this new kind of beams. Hence, one of the ELIMED task, will be the definition of procedures aiming to obtain an absolute dose measure at the end of the transport beamline with an accuracy as close as possible to the one required for clinical applications (i.e. of the order of 5% or less). Relative dosimetry procedures must be established, as well: they are necessary in order to determine and verify the beam dose distributions and to monitor the beam fluence and the energetic spectra during irradiations. Radiochromic films, CR39, Faraday Cup, Secondary Emission Monitor (SEM) and transmission ionization chamber will be considered, designed and studied in order to perform a fully dosimetric characterization of the ELIMED proton beam.

  17. The absolute differential calculus (calculus of tensors)

    CERN Document Server

    Levi-Civita, Tullio

    2013-01-01

    Written by a towering figure of twentieth-century mathematics, this classic examines the mathematical background necessary for a grasp of relativity theory. Tullio Levi-Civita provides a thorough treatment of the introductory theories that form the basis for discussions of fundamental quadratic forms and absolute differential calculus, and he further explores physical applications.Part one opens with considerations of functional determinants and matrices, advancing to systems of total differential equations, linear partial differential equations, algebraic foundations, and a geometrical intro

  18. Absolute vs. Relative Notion of Wealth Changes

    OpenAIRE

    2009-01-01

    This paper discusses solutions derived from lottery experiments using two alternative assumptions: that people perceive wealth changes as absolute amounts of money; and that people consider wealth changes as a proportion of some reference value dependant on the context of the problem under consideration. The former assumption leads to the design of Prospect Theory, the latter - to a solution closely resembling the utility function hypothesized by Markowitz (1952B). This paper presents several...

  19. Measurement of absolute gravity acceleration in Firenze

    Science.gov (United States)

    de Angelis, M.; Greco, F.; Pistorio, A.; Poli, N.; Prevedelli, M.; Saccorotti, G.; Sorrentino, F.; Tino, G. M.

    2011-01-01

    This paper reports the results from the accurate measurement of the acceleration of gravity g taken at two separate premises in the Polo Scientifico of the University of Firenze (Italy). In these laboratories, two separate experiments aiming at measuring the Newtonian constant and testing the Newtonian law at short distances are in progress. Both experiments require an independent knowledge on the local value of g. The only available datum, pertaining to the italian zero-order gravity network, was taken more than 20 years ago at a distance of more than 60 km from the study site. Gravity measurements were conducted using an FG5 absolute gravimeter, and accompanied by seismic recordings for evaluating the noise condition at the site. The absolute accelerations of gravity at the two laboratories are (980 492 160.6 ± 4.0) μGal and (980 492 048.3 ± 3.0) μGal for the European Laboratory for Non-Linear Spectroscopy (LENS) and Dipartimento di Fisica e Astronomia, respectively. Other than for the two referenced experiments, the data here presented will serve as a benchmark for any future study requiring an accurate knowledge of the absolute value of the acceleration of gravity in the study region.

  20. Measurement of absolute gravity acceleration in Firenze

    Directory of Open Access Journals (Sweden)

    M. de Angelis

    2011-01-01

    Full Text Available This paper reports the results from the accurate measurement of the acceleration of gravity g taken at two separate premises in the Polo Scientifico of the University of Firenze (Italy. In these laboratories, two separate experiments aiming at measuring the Newtonian constant and testing the Newtonian law at short distances are in progress. Both experiments require an independent knowledge on the local value of g. The only available datum, pertaining to the italian zero-order gravity network, was taken more than 20 years ago at a distance of more than 60 km from the study site. Gravity measurements were conducted using an FG5 absolute gravimeter, and accompanied by seismic recordings for evaluating the noise condition at the site. The absolute accelerations of gravity at the two laboratories are (980 492 160.6 ± 4.0 μGal and (980 492 048.3 ± 3.0 μGal for the European Laboratory for Non-Linear Spectroscopy (LENS and Dipartimento di Fisica e Astronomia, respectively. Other than for the two referenced experiments, the data here presented will serve as a benchmark for any future study requiring an accurate knowledge of the absolute value of the acceleration of gravity in the study region.

  1. Latency and activation in the control of TGF-beta

    Science.gov (United States)

    Barcellos-Hoff, M. H.; Chatterjee, A. (Principal Investigator)

    1996-01-01

    The biological activity of the transforming growth factor-beta's (TGF-beta)3 is tightly controlled by their persistence in the extracellular compartment as latent complexes. Each of the three mammalian isoform genes encodes a product that is cleaved intracellularly to form two polypeptides, each of which dimerizes. Mature TGF-beta, a 24 kD homodimer, is noncovalently associated with the 80 kD latency-associated peptide (LAP). LAP is a fundamental component of TGF-beta that is required for its efficient secretion, prevents it from binding to ubiquitous cell surface receptors, and maintains its availability in a large extracellular reservoir that is readily accessed by activation. This latent TGF-beta complex (LTGF-beta) is secreted by all cells and is abundant both in circulating forms and bound to the extracellular matrix. Activation describes the collective events leading to the release of TGF-beta. Despite the importance of TGF-beta regulation of growth and differentiation in physiological and malignant tissue processes, remarkably little is known about the mechanisms of activation in situ. Recent studies of irradiated mammary gland reveal certain features of TGF-beta 1 activation that may shed light on its regulation and potential roles in the normal and neoplastic mammary gland.

  2. The latency complex: the dead hand of anti-development.

    Science.gov (United States)

    Proner, Barry D

    2017-09-01

    It is common knowledge that the same phenomena can be viewed in a variety of ways. This paper considers the implications of a constellation observed in some adult patients who have increasingly reminded the author of some of the children of latency age with whom he has also worked. In the literature these patients may also have been thought about in terms of 'defences of the self' (Fordham), patients who are 'difficult to reach' (Joseph), 'psychic retreats' (Steiner), and those who make 'attacks on linking' (Bion). They may equally be considered in terms of schizoid, narcissistic or borderline personalities, or as showing features on the autistic spectrum, such as mindlessness and extreme obsessionality. Writers such as Helene Deutsch with her concept of an 'as-if personality', Winnicott with his 'false self', and Rosenfeld, discussing the split-off parts of the personality in narcissistic patients, have also offered much to think about in their consideration of some of these phenomena. This paper proposes yet another vertex - the author's own imaginative conjecture - that is by no means mutually exclusive of any of these others. © 2017, The Society of Analytical Psychology.

  3. Latencies in BOLD response during visual attention processes.

    Science.gov (United States)

    Kellermann, Thilo; Reske, Martina; Jansen, Andreas; Satrapi, Peyman; Shah, N Jon; Schneider, Frank; Habel, Ute

    2011-04-22

    One well-investigated division of attentional processes focuses on alerting, orienting and executive control, which can be assessed applying the attentional network test (ANT). The goal of the present study was to add further knowledge about the temporal dynamics of relevant neural correlates. As a right hemispheric dominance for alerting and orienting has previously been reported for intrinsic but not for phasic alertness, we additionally addressed a potential impact of this lateralization of attention by employing a lateralized version of the ANT, capturing phasic alertness processes. Sixteen healthy subjects underwent event-related functional magnetic resonance imaging (fMRI) while performing the ANT. Analyses of BOLD magnitude replicated the engagement of a fronto-parietal network in the attentional subsystems. The amplitudes of the attentional contrasts interacted with visual field presentation in the sense that the thalamus revealed a greater involvement for spatially cued items presented in the left visual field. Comparisons of BOLD latencies in visual cortices, first, verified faster BOLD responses following contra-lateral stimulus presentation. Second and more importantly, we identified attention-modulated activation in secondary visual and anterior cingulate cortices. Results are discussed in terms of bottom-up and lateralization processes. Although intrinsic and phasic alertness are distinct cognitive processes, we propose that neural substrates of intrinsic alertness may be accessed by phasic alertness provided that the attention-dominant (i.e., the right) hemisphere is activated directly by a warning stimulus.

  4. Software for analysing multifocal visual evoked potential signal latency progression.

    Science.gov (United States)

    de Santiago, L; Klistorner, A; Ortiz, M; Fernández-Rodríguez, A J; Rodríguez Ascariz, J M; Barea, R; Miguel-Jiménez, J M; Boquete, L

    2015-04-01

    This paper describes a new non-commercial software application (mfVEP(2)) developed to process multifocal visual-evoked-potential (mfVEP) signals in latency (monocular and interocular) progression studies. The software performs analysis by cross-correlating signals from the same patients. The criteria applied by the software include best channels, signal window, cross-correlation limits and signal-to-noise ratio (SNR). Software features include signal display comparing different tests and groups of sectors (quadrants, rings and hemispheres). The software's performance and capabilities are demonstrated on the results obtained from a patient with acute optic neuritis who underwent 9 follow-up mfVEP tests. Numerical values and graphics are presented and discussed for this case. The authors present a software application used to study progression in mfVEP signals. It is also useful in research projects designed to improve mfVEP techniques. This software makes it easier for users to manage the signals and allows them to choose various ways of selecting signals and representing results. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Role of Frenular Web Preservation on Ejaculation Latency Time

    Directory of Open Access Journals (Sweden)

    Alborz Salavati

    2012-10-01

    Full Text Available Premature ejaculation (PE is one of prevalent male sexual dysfunctions worldwide. Despite many psychiatric backgrounds, yet there are speculations about organic etiologies considering both anatomic and physiologic points of view. This survey assesses effect of frenular web preservation on premature ejaculation. One thousand and forty otherwise healthy men being visited for urolithiasis (asymptomatic patients were asked for PE according to the International Society of Sexual Medicine definition criteria as intravaginal ejaculation latency time (IELT less than a minute according to stop watch checked by patients' partner and were examined for presence of frenular web. Frenular web defined as a residual of frenulum after a circumcision. Overall prevalence of PE was 18.2% (n=102. We found the presence of frenulum at physical examination in 255 out of 560 (45.5%. Prevalence of PE was 20.7% (n=53 and 16% (n=49 in patients with frenular web preserved and without it, respectively. PE was higher among the men with frenulum preserved; but no statistically significant differences were seen (P=0.70. We did not find any relationship between frenular web and PE, and concerns about this, during circumcision, may not be justified. PE is a not only a problem of local anatomical condition but many psychological and neurological factors could interact with it.

  6. Analysis of Latency Performance of Bluetooth Low Energy (BLE) Networks

    Science.gov (United States)

    Cho, Keuchul; Park, Woojin; Hong, Moonki; Park, Gisu; Cho, Wooseong; Seo, Jihoon; Han, Kijun

    2015-01-01

    Bluetooth Low Energy (BLE) is a short-range wireless communication technology aiming at low-cost and low-power communication. The performance evaluation of classical Bluetooth device discovery have been intensively studied using analytical modeling and simulative methods, but these techniques are not applicable to BLE, since BLE has a fundamental change in the design of the discovery mechanism, including the usage of three advertising channels. Recently, there several works have analyzed the topic of BLE device discovery, but these studies are still far from thorough. It is thus necessary to develop a new, accurate model for the BLE discovery process. In particular, the wide range settings of the parameters introduce lots of potential for BLE devices to customize their discovery performance. This motivates our study of modeling the BLE discovery process and performing intensive simulation. This paper is focused on building an analytical model to investigate the discovery probability, as well as the expected discovery latency, which are then validated via extensive experiments. Our analysis considers both continuous and discontinuous scanning modes. We analyze the sensitivity of these performance metrics to parameter settings to quantitatively examine to what extent parameters influence the performance metric of the discovery processes. PMID:25545266

  7. Analysis of latency performance of bluetooth low energy (BLE) networks.

    Science.gov (United States)

    Cho, Keuchul; Park, Woojin; Hong, Moonki; Park, Gisu; Cho, Wooseong; Seo, Jihoon; Han, Kijun

    2014-12-23

    Bluetooth Low Energy (BLE) is a short-range wireless communication technology aiming at low-cost and low-power communication. The performance evaluation of classical Bluetooth device discovery have been intensively studied using analytical modeling and simulative methods, but these techniques are not applicable to BLE, since BLE has a fundamental change in the design of the discovery mechanism, including the usage of three advertising channels. Recently, there several works have analyzed the topic of BLE device discovery, but these studies are still far from thorough. It is thus necessary to develop a new, accurate model for the BLE discovery process. In particular, the wide range settings of the parameters introduce lots of potential for BLE devices to customize their discovery performance. This motivates our study of modeling the BLE discovery process and performing intensive simulation. This paper is focused on building an analytical model to investigate the discovery probability, as well as the expected discovery latency, which are then validated via extensive experiments. Our analysis considers both continuous and discontinuous scanning modes. We analyze the sensitivity of these performance metrics to parameter settings to quantitatively examine to what extent parameters influence the performance metric of the discovery processes.

  8. Toxicokinetics and absolute oral bioavailability of melamine in broiler chickens.

    Science.gov (United States)

    Poapolathep, S; Klangkaew, N; Arreesrisom, P; Isariyodom, S; Sugita-Konishi, Y; Kumagai, S; Poapolathep, A

    2015-02-01

    The objective of this study was to investigate the toxicokinetic characteristics of melamine in broilers due to the limited information available for livestock. Melamine was then administered to broiler chickens at an intravenous (i.v.) or oral (p.o.) dosage of 5.5 mg/kg of body weight, and plasma samples were collected up to 48 h. The concentration of melamine in each plasma sample was analyzed using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Melamine was measurable up to 24 h after i.v. and p.o. administration. A one-compartment model was developed to describe the toxicokinetics of melamine in broilers. Following i.v. administration, the values for the elimination half-life (t(1/2β)), the volume of distribution (Vd ), and the clearance (CL) were 4.42 ± 1.02 h, 00.52 ± 0.18 L/kg, and 0.08 ± 0.01 L/h/kg, respectively. The absolute oral bioavailability (F) was 95.63 ± 3.54%. The results suggest that most of the administered melamine is favorably absorbed from the alimentary tract and rapidly cleared by the kidneys in broiler chickens.

  9. Subtle role of latency for information diffusion in online social networks

    Science.gov (United States)

    Xiong, Fei; Wang, Xi-Meng; Cheng, Jun-Jun

    2016-10-01

    Information diffusion in online social networks is induced by the event of forwarding information for users, and latency exists widely in user spreading behaviors. Little work has been done to reveal the effect of latency on the diffusion process. In this paper, we propose a propagation model in which nodes may suspend their spreading actions for a waiting period of stochastic length. These latent nodes may recover their activity again. Meanwhile, the mechanism of forwarding information is also introduced into the diffusion model. Mean-field analysis and numerical simulations indicate that our model has three nontrivial results. First, the spreading threshold does not correlate with latency in neither homogeneous nor heterogeneous networks, but depends on the spreading and refractory parameter. Furthermore, latency affects the diffusion process and changes the infection scale. A large or small latency parameter leads to a larger final diffusion extent, but the intrinsic dynamics is different. Large latency implies forwarding information rapidly, while small latency prevents nodes from dropping out of interactions. In addition, the betweenness is a better descriptor to identify influential nodes in the model with latency, compared with the coreness and degree. These results are helpful in understanding some collective phenomena of the diffusion process and taking measures to restrain a rumor in social networks. Project supported by the National Natural Science Foundation of China (Grant Nos. 61401015 and 61271308), the Fundamental Research Funds for the Central Universities, China (Grant No. 2014JBM018), and the Talent Fund of Beijing Jiaotong University, China (Grant No. 2015RC013).

  10. Achieving low latency and energy consumption by 5G TDD mode optimization

    DEFF Research Database (Denmark)

    Lähetkangas, Eeva; Pajukoski, Kari; Vihriälä, Jaakko

    2014-01-01

    The target for a new 5G radio access technology is to support multi-Gbps and ms latency connectivity simultaneously at noticeably lower energy consumption and cost compared to the existing 4G technologies, such as LTE-Advanced. Extremely short air interface latency is required to achieve these re...

  11. Long-latency auditory evoked potentials with verbal and nonverbal stimuli,

    Directory of Open Access Journals (Sweden)

    Sheila Jacques Oppitz

    2015-12-01

    Full Text Available ABSTRACT INTRODUCTION: Long-latency auditory evoked potentials represent the cortical activity related to attention, memory, and auditory discrimination skills. Acoustic signal processing occurs differently between verbal and nonverbal stimuli, influencing the latency and amplitude patterns. OBJECTIVE: To describe the latencies of the cortical potentials P1, N1, P2, N2, and P3, as well as P3 amplitude, with different speech stimuli and tone bursts, and to classify them in the presence and absence of these data. METHODS: A total of 30 subjects with normal hearing were assessed, aged 18-32 years old, matched by gender. Nonverbal stimuli were used (tone burst; 1000 Hz - frequent and 4000 Hz - rare; and verbal (/ba/ - frequent; /ga/, /da/, and /di/ - rare. RESULTS: Considering the component N2 for tone burst, the lowest latency found was 217.45 ms for the BA/DI stimulus; the highest latency found was 256.5 ms. For the P3 component, the shortest latency with tone burst stimuli was 298.7 with BA/GA stimuli, the highest, was 340 ms. For the P3 amplitude, there was no statistically significant difference among the different stimuli. For latencies of components P1, N1, P2, N2, P3, there were no statistical differences among them, regardless of the stimuli used. CONCLUSION: There was a difference in the latency of potentials N2 and P3 among the stimuli employed but no difference was observed for the P3 amplitude.

  12. Low Latency Audio Video: Potentials for Collaborative Music Making through Distance Learning

    Science.gov (United States)

    Riley, Holly; MacLeod, Rebecca B.; Libera, Matthew

    2016-01-01

    The primary purpose of this study was to examine the potential of LOw LAtency (LOLA), a low latency audio visual technology designed to allow simultaneous music performance, as a distance learning tool for musical styles in which synchronous playing is an integral aspect of the learning process (e.g., jazz, folk styles). The secondary purpose was…

  13. Using Differential Reinforcement to Decrease Academic Response Latencies of an Adolescent with Acquired Brain Injury

    Science.gov (United States)

    Heinicke, Megan R.; Carr, James E.; Mozzoni, Michael P.

    2009-01-01

    The present study investigated the effects of contingency-specifying rules and a token economy to decrease the latency to comply with academic instructions by a 16-year-old girl with acquired brain injury. Results showed that treatment was successful in reducing academic response latencies. These results replicate previous research in which…

  14. MAC Layer Enhancements for Ultra-Reliable Low-Latency Communications in Cellular Networks

    DEFF Research Database (Denmark)

    Gerardino, Guillermo Andrés Pocovi; Alvarez, Beatriz Soret; Pedersen, Klaus I.

    2017-01-01

    Ultra-reliable low-latency communications (URLLC) entail the transmission of sporadic and small packets, with low latency and very high reliability. Among many potential areas of optimization for URLLC, the problems of large delays during HARQ retransmissions, and inaccurate link adaptation as a ...

  15. Longer brainstem auditory evoked response latencies of individuals with fragile X syndrome related to sedation.

    Science.gov (United States)

    Miezejeski, C M; Heaney, G; Belser, R; Brown, W T; Jenkins, E C; Sersen, E A

    1997-04-18

    Brainstem auditory evoked response latencies were studies in 75 males (13 with fragile X syndrome, 18 with mental retardation due to other causes, and 44 with no disability). Latency values were obtained for each ear for the positive deflections of waves I (P1), III (P3), and V (P5). Some individuals with mental retardation required sedation. Contrary to previous report, latencies obtained for individuals with fragile X did not differ from those obtained for persons without mental retardation. Persons receiving sedation, whether or not their retardation was due to fragile X, had longer latencies for wave P5 than persons who did not receive sedation. This effect of sedation may also explain the previously reported increased latencies for persons with fragile X.

  16. Construction and Evaluation of an Ultra Low Latency Frameless Renderer for VR.

    Science.gov (United States)

    Friston, Sebastian; Steed, Anthony; Tilbury, Simon; Gaydadjiev, Georgi

    2016-04-01

    Latency - the delay between a user's action and the response to this action - is known to be detrimental to virtual reality. Latency is typically considered to be a discrete value characterising a delay, constant in time and space - but this characterisation is incomplete. Latency changes across the display during scan-out, and how it does so is dependent on the rendering approach used. In this study, we present an ultra-low latency real-time ray-casting renderer for virtual reality, implemented on an FPGA. Our renderer has a latency of ~1 ms from 'tracker to pixel'. Its frameless nature means that the region of the display with the lowest latency immediately follows the scan-beam. This is in contrast to frame-based systems such as those using typical GPUs, for which the latency increases as scan-out proceeds. Using a series of high and low speed videos of our system in use, we confirm its latency of ~1 ms. We examine how the renderer performs when driving a traditional sequential scan-out display on a readily available HMO, the Oculus Rift OK2. We contrast this with an equivalent apparatus built using a GPU. Using captured human head motion and a set of image quality measures, we assess the ability of these systems to faithfully recreate the stimuli of an ideal virtual reality system - one with a zero latency tracker, renderer and display running at 1 kHz. Finally, we examine the results of these quality measures, and how each rendering approach is affected by velocity of movement and display persistence. We find that our system, with a lower average latency, can more faithfully draw what the ideal virtual reality system would. Further, we find that with low display persistence, the sensitivity to velocity of both systems is lowered, but that it is much lower for ours.

  17. The role of antigen presenting cells in the induction of HIV-1 latency in resting CD4(+) T-cells.

    Science.gov (United States)

    Kumar, Nitasha A; Cheong, Karey; Powell, David R; da Fonseca Pereira, Candida; Anderson, Jenny; Evans, Vanessa A; Lewin, Sharon R; Cameron, Paul U

    2015-09-11

    Combination antiretroviral therapy (cART) is able to control HIV-1 viral replication, however long-lived latent infection in resting memory CD4(+) T-cells persist. The mechanisms for establishment and maintenance of latent infection in resting memory CD4(+) T-cells remain unclear. Previously we have shown that HIV-1 infection of resting CD4(+) T-cells co-cultured with CD11c(+) myeloid dendritic cells (mDC) produced a population of non-proliferating T-cells with latent infection. Here we asked whether different antigen presenting cells (APC), including subpopulations of DC and monocytes, were able to induce post-integration latent infection in resting CD4(+) T-cells, and examined potential cell interactions that may be involved using RNA-seq. mDC (CD1c(+)), SLAN(+) DC and CD14(+) monocytes were most efficient in stimulating proliferation of CD4(+) T-cells during syngeneic culture and in generating post-integration latent infection in non-proliferating CD4(+) T-cells following HIV-1 infection of APC-T cell co-cultures. In comparison, plasmacytoid DC (pDC) and B-cells did not induce latent infection in APC-T-cell co-cultures. We compared the RNA expression profiles of APC subpopulations that could and could not induce latency in non-proliferating CD4(+) T-cells. Gene expression analysis, comparing the CD1c(+) mDC, SLAN(+) DC and CD14(+) monocyte subpopulations to pDC identified 53 upregulated genes that encode proteins expressed on the plasma membrane that could signal to CD4(+) T-cells via cell-cell interactions (32 genes), immune checkpoints (IC) (5 genes), T-cell activation (9 genes), regulation of apoptosis (5 genes), antigen presentation (1 gene) and through unknown ligands (1 gene). APC subpopulations from the myeloid lineage, specifically mDC subpopulations and CD14(+) monocytes, were able to efficiently induce post-integration HIV-1 latency in non-proliferating CD4(+) T-cells in vitro. Inhibition of key pathways involved in mDC-T-cell interactions and HIV-1

  18. Effects of musical training and absolute pitch ability on event-related activity in response to sine tones.

    Science.gov (United States)

    Wayman, J W; Frisina, R D; Walton, J P; Hantz, E C; Crummer, G C

    1992-06-01

    The neural correlates of music perception have received relatively little scientific attention. The neural activity of listeners without musical training (N = 11), highly trained musicians (N = 14), and musicians possessing "absolute pitch" (AP) ability (N = 10) have been measured. Major differences were observed in the P3, an endogenous event-related potential (ERP), which is thought to be a neurophysiological manifestation of working memory processing. The P3 was elicited using the classical "oddball" paradigm with a sine-tone series. Subjects' musical backgrounds were evaluated with a survey questionnaire. AP ability was verified with an objective pitch identification test. The P3 amplitude, latency and wave shape were evaluated along with each subjects' performance score and musical background. The AP subjects showed a significantly smaller P3 amplitude than either the musicians or nonmusicians, which were nearly identical. The P3 latency was shortest for the AP subjects, and was longer for the nonmusicians. Performance scores were uniformly high in all three groups. It is concluded that AP subjects do indeed exhibit P3 ERPs, albeit with smaller amplitudes and shorter latencies. The differences in neural activity between the musicians and AP subjects were not due to musical training, as the AP subjects had similar musical backgrounds to the musician group. It is also concluded that persons with the AP ability may have superior auditory sensitivity at cortical levels and/or use unique neuropsychological strategies when processing tones.

  19. Extravehicular Activity Operations Concepts Under Communication Latency and Bandwidth Constraints

    Science.gov (United States)

    Beaton, Kara H.; Chappell, Steven P.; Abercromby, Andrew F. J.; Miller, Matthew J.; Nawotniak, Shannon Kobs; Hughes, Scott; Brady, Allyson; Lim, Darlene S. S.

    2017-01-01

    The Biologic Analog Science Associated with Lava Terrains (BASALT) project is a multi-year program dedicated to iteratively develop, implement, and evaluate concepts of operations (ConOps) and supporting capabilities intended to enable and enhance human scientific exploration of Mars. This pa-per describes the planning, execution, and initial results from the first field deployment, referred to as BASALT-1, which consisted of a series of 10 simulated extravehicular activities (EVAs) on volcanic flows in Idaho's Craters of the Moon (COTM) National Monument. The ConOps and capabilities deployed and tested during BASALT-1 were based on previous NASA trade studies and analog testing. Our primary research question was whether those ConOps and capabilities work acceptably when performing real (non-simulated) biological and geological scientific exploration under 4 different Mars-to-Earth communication conditions: 5 and 15 min one-way light time (OWLT) communication latencies and low (0.512 Mb/s uplink, 1.54 Mb/s downlink) and high (5.0 Mb/s uplink, 10.0 Mb/s downlink) bandwidth conditions representing the lower and higher limits of technical communication capabilities currently proposed for future human exploration missions. The synthesized results of BASALT-1 with respect to the ConOps and capabilities assessment were derived from a variety of sources, including EVA task timing data, network analytic data, and subjective ratings and comments regarding the scientific and operational acceptability of the ConOp and the extent to which specific capabilities were enabling and enhancing, and are presented here. BASALT-1 established preliminary findings that baseline ConOp, software systems, and communication protocols were scientifically and operationally acceptable with minor improvements desired by the "Mars" extravehicular (EV) and intravehicular (IV) crewmembers, but unacceptable with improvements required by the "Earth" Mission Support Center. These data will provide a

  20. Fatal snake bites – sociodemography, latency pattern of injuries

    Science.gov (United States)

    2013-01-01

    Background India is a thickly populated country; apart from having biodiversity among people, climate does change from place to place. Western Ghats of South India harbors variety of plantations and diverse creatures. Agriculture is the primary occupation of the people and some tribes living in these regions. Here majority are callous/ ignorant in employing neither advanced farming techniques nor safety precautions, hence are exposed to bites and stings by animals. Of these, snake bites cause significant mortality and morbidity. Proper care for some of these individuals is out of reach. Identification of offending snake, snake bite injury or findings of envenomation is a key not only for the administration of antisnake venom but also for the victim to realize that he needs an expert care. Unless he believes it to be a critical snake bite and not a thorn prick, scorpion sting or a spider bite he will not approach a health care provider. To know about these dangerous signs that may help the victim to realize it as a case of snake bite, current study is employed on fatal cases in this region. Methods 60 fatal snakebite cases were studied retrospectively for 5 years with an objective to know the socio-demography, latency and pattern of injuries in rural Southern India. Results Most of the victims were males, in the age group of 31-50 years and were at risk of snake bites while farming. Large sample of subjects approached traditional therapists and were deprived of essential care in the critical first few hours after snake bite. Fang marks (90%), local ecchymoses (50%) and internal hemorrhage (28.3%), were the frequent demonstrable signs appreciated at autopsy. Conclusion Snakebite is a neglected, endemic, occupational (farming) disease of the poor and there is need for National Snakebite Prevention Programme for curtailing this menace. PMID:23522302

  1. Implications of event entry latency on anesthesia information management decision support systems.

    Science.gov (United States)

    Epstein, Richard H; Dexter, Franklin; Ehrenfeld, Jesse M; Sandberg, Warren S

    2009-03-01

    Decision support systems (DSSs) are being developed to use events entered in anesthesia information management systems (AIMS) for quality of care, compliance, billing, documentation, and management purposes. DSS performance is impacted by latency from the actual time an event occurs to when it is written to the database, as well as how often the database is queried. Such latencies may result in poor DSS recommendations. We analyzed approximately 48,000 cases at Hospital A for latency of two DSS prototype events, Surgery Begin and Surgery End. Each latency was measured from 1) the time that the event was recorded in the AIMS database as having taken place to 2) the time when the first DSS query would have been executed after the documentation of that event by the provider. The effects on latency of 1, 5, and 10 min query intervals were determined. Latencies for Surgery Begin and Surgery End were compared with those of Hospital B, where a different AIMS was used. Network delays and the event processing time of the AIMS contributed <1 s and 30 s, respectively, to latency. Average latencies for the two studied events were approximately half of the query interval, the expected value if the events occurred randomly within each interval. However, the longest 5% of latencies exceeded the query interval. This was not due to providers editing the times of the Begin or End Surgery events, as each occurred in only 0.7% of cases. Although the median latencies for the two events were longer at Hospital B than Hospital A by a few minutes, the 90th and 95th percentiles of the latencies were much longer at Hospital B (8-30 min, depending on the query interval and the percentile). DSS performance is influenced by the timeliness of documentation, the incidence of missing documentation and the query interval. Facilities using a DSS, including electronic whiteboards showing patient status, should assess the latencies of the measured events and critique the influence of the latencies on

  2. Achieving Climate Change Absolute Accuracy in Orbit

    Science.gov (United States)

    Wielicki, Bruce A.; Young, D. F.; Mlynczak, M. G.; Thome, K. J; Leroy, S.; Corliss, J.; Anderson, J. G.; Ao, C. O.; Bantges, R.; Best, F.; Bowman, K.; Brindley, H.; Butler, J. J.; Collins, W.; Dykema, J. A.; Doelling, D. R.; Feldman, D. R.; Fox, N.; Huang, X.; Holz, R.; Huang, Y.; Jennings, D.; Jin, Z.; Johnson, D. G.; Jucks, K.; Kato, S.; Kratz, D. P.; Liu, X.; Lukashin, C.; Mannucci, A. J.; Phojanamongkolkij, N.; Roithmayr, C. M.; Sandford, S.; Taylor, P. C.; Xiong, X.

    2013-01-01

    The Climate Absolute Radiance and Refractivity Observatory (CLARREO) mission will provide a calibration laboratory in orbit for the purpose of accurately measuring and attributing climate change. CLARREO measurements establish new climate change benchmarks with high absolute radiometric accuracy and high statistical confidence across a wide range of essential climate variables. CLARREO's inherently high absolute accuracy will be verified and traceable on orbit to Système Internationale (SI) units. The benchmarks established by CLARREO will be critical for assessing changes in the Earth system and climate model predictive capabilities for decades into the future as society works to meet the challenge of optimizing strategies for mitigating and adapting to climate change. The CLARREO benchmarks are derived from measurements of the Earth's thermal infrared spectrum (5-50 micron), the spectrum of solar radiation reflected by the Earth and its atmosphere (320-2300 nm), and radio occultation refractivity from which accurate temperature profiles are derived. The mission has the ability to provide new spectral fingerprints of climate change, as well as to provide the first orbiting radiometer with accuracy sufficient to serve as the reference transfer standard for other space sensors, in essence serving as a "NIST [National Institute of Standards and Technology] in orbit." CLARREO will greatly improve the accuracy and relevance of a wide range of space-borne instruments for decadal climate change. Finally, CLARREO has developed new metrics and methods for determining the accuracy requirements of climate observations for a wide range of climate variables and uncertainty sources. These methods should be useful for improving our understanding of observing requirements for most climate change observations.

  3. Absolute calibration of the Auger fluorescence detectors

    Energy Technology Data Exchange (ETDEWEB)

    Bauleo, P.; Brack, J.; Garrard, L.; Harton, J.; Knapik, R.; Meyhandan, R.; Rovero, A.C.; /Buenos Aires, IAFE; Tamashiro, A.; Warner, D.

    2005-07-01

    Absolute calibration of the Pierre Auger Observatory fluorescence detectors uses a light source at the telescope aperture. The technique accounts for the combined effects of all detector components in a single measurement. The calibrated 2.5 m diameter light source fills the aperture, providing uniform illumination to each pixel. The known flux from the light source and the response of the acquisition system give the required calibration for each pixel. In the lab, light source uniformity is studied using CCD images and the intensity is measured relative to NIST-calibrated photodiodes. Overall uncertainties are presently 12%, and are dominated by systematics.

  4. Absolute quantification of myocardial blood flow.

    Science.gov (United States)

    Yoshinaga, Keiichiro; Manabe, Osamu; Tamaki, Nagara

    2016-07-21

    With the increasing availability of positron emission tomography (PET) myocardial perfusion imaging, the absolute quantification of myocardial blood flow (MBF) has become popular in clinical settings. Quantitative MBF provides an important additional diagnostic or prognostic information over conventional visual assessment. The success of MBF quantification using PET/computed tomography (CT) has increased the demand for this quantitative diagnostic approach to be more accessible. In this regard, MBF quantification approaches have been developed using several other diagnostic imaging modalities including single-photon emission computed tomography, CT, and cardiac magnetic resonance. This review will address the clinical aspects of PET MBF quantification and the new approaches to MBF quantification.

  5. ABSOLUT LOMO绝对创意

    Institute of Scientific and Technical Information of China (English)

    婷婷(整理)

    2007-01-01

    ABSOLUT与创意素来有着不解之缘。由Andy Warhal的ABSOLUT WARHOL至今,已有超过400位不同领域的创意大师为ABSOLUT的当代艺术宝库贡献了自己的得意之作。ABSOLUT的创意仿佛永远不会枯竭,而一系列的作品也让惊喜从未落空。

  6. Absolute Priority for a Vehicle in VANET

    Science.gov (United States)

    Shirani, Rostam; Hendessi, Faramarz; Montazeri, Mohammad Ali; Sheikh Zefreh, Mohammad

    In today's world, traffic jams waste hundreds of hours of our life. This causes many researchers try to resolve the problem with the idea of Intelligent Transportation System. For some applications like a travelling ambulance, it is important to reduce delay even for a second. In this paper, we propose a completely infrastructure-less approach for finding shortest path and controlling traffic light to provide absolute priority for an emergency vehicle. We use the idea of vehicular ad-hoc networking to reduce the imposed travelling time. Then, we simulate our proposed protocol and compare it with a centrally controlled traffic light system.

  7. Musical Activity Tunes Up Absolute Pitch Ability

    DEFF Research Database (Denmark)

    Dohn, Anders; Garza-Villarreal, Eduardo A.; Ribe, Lars Riisgaard

    2014-01-01

    Absolute pitch (AP) is the ability to identify or produce pitches of musical tones without an external reference. Active AP (i.e., pitch production or pitch adjustment) and passive AP (i.e., pitch identification) are considered to not necessarily coincide, although no study has properly compared...... that APs generally undershoot when adjusting musical pitch, a tendency that decreases when musical activity increases. Finally, APs are less accurate when adjusting the pitch to black key targets than to white key targets. Hence, AP ability may be partly practice-dependent and we speculate that APs may...

  8. Development of an absolute neutron dosimeter

    Energy Technology Data Exchange (ETDEWEB)

    Acevedo, C; Birstein, L; Loyola, H [Section de Desarrollos Innovativos, Comision Chilena de EnergIa Nuclear (CCHEN), Casilla 188-D, Santiago (Chile)], E-mail: lbirstei@cchen.cl

    2008-11-01

    An Absolute Neutron Dosimeter was developed to be used as a calibration standard for the Radiation Metrology Laboratory at CCHEN. The main component of the Dosimeter consists of a Proportional Counter of cylindrical shape, with Polyethylene walls and Ethylene gas in its interior. It includes a cage shaped arrangement of graphite bars that operates like the Proportional Counter cathode and a tungsten wire of 25 {mu}m in diameter {mu}m as the anode. Results of a Montecarlo modeling for the Dosimeter operation and results of tests and measurements performed with a radioactive source are presented.

  9. Musical Activity Tunes Up Absolute Pitch Ability

    DEFF Research Database (Denmark)

    Dohn, Anders; Garza-Villarreal, Eduardo A.; Ribe, Lars Riisgaard

    2014-01-01

    Absolute pitch (AP) is the ability to identify or produce pitches of musical tones without an external reference. Active AP (i.e., pitch production or pitch adjustment) and passive AP (i.e., pitch identification) are considered to not necessarily coincide, although no study has properly compared...... that APs generally undershoot when adjusting musical pitch, a tendency that decreases when musical activity increases. Finally, APs are less accurate when adjusting the pitch to black key targets than to white key targets. Hence, AP ability may be partly practice-dependent and we speculate that APs may...

  10. Latency of saccadic eye movement during contraction of bilateral and unilateral shoulder girdle elevators.

    Science.gov (United States)

    Fujiwara, Katsuo; Kunita, Kenji; Toyama, Hiroshi

    2003-02-01

    We compared the timed latencies of saccadic eye movement during isometric contraction of the bilateral and unilateral shoulder girdle elevators in a sitting posture. Muscle contraction force was increased in 10% increments from 0% to 60% of the maximal voluntary contraction (MVC) of each side. Saccadic latency was measured as the latency to the beginning of eye movement toward the lateral target that was moved at random intervals in 20 degree amplitude jumps. Eye movement was measured using the electro-oculogram technique. During bilateral contraction, saccadic latency decreased until 30% MVC and then began to increase at 40% MVC. During unilateral contraction, saccadic latency decreased until 30% MVC in a similar pattern as in bilateral condition, was constant from 30% MVC to 50% MVC, followed by a slight increase at 60% MVC. The saccadic latencies at 10% and 40-60% MVC were significantly shorter during unilateral contraction than bilateral contraction. Thus, the relative force for producing a marked shortening of saccadic latency is observed within a wider range during unilateral contraction than bilateral contraction.

  11. Fault and Error Latency Under Real Workload: an Experimental Study. Ph.D. Thesis

    Science.gov (United States)

    Chillarege, Ram

    1986-01-01

    A practical methodology for the study of fault and error latency is demonstrated under a real workload. This is the first study that measures and quantifies the latency under real workload and fills a major gap in the current understanding of workload-failure relationships. The methodology is based on low level data gathered on a VAX 11/780 during the normal workload conditions of the installation. Fault occurrence is simulated on the data, and the error generation and discovery process is reconstructed to determine latency. The analysis proceeds to combine the low level activity data with high level machine performance data to yield a better understanding of the phenomena. A strong relationship exists between latency and workload and that relationship is quantified. The sampling and reconstruction techniques used are also validated. Error latency in the memory where the operating system resides was studied using data on the physical memory access. Fault latency in the paged section of memory was determined using data from physical memory scans. Error latency in the microcontrol store was studied using data on the microcode access and usage.

  12. THE PEAK LATENCY OF ORBITAL PRESACCADIC SPIKE POTENTIAL WITH HORIZONTAL EYE MOVEMENTS

    Institute of Scientific and Technical Information of China (English)

    单扬; MarkL.Moster; RichardA.Roemer[

    1996-01-01

    Purpose.To investigate the peak latency of the orbital presaccedic spike potential (SP) with horizontal eyemovement in normals.Methods. Orbital SP was recorded in 28 normal subjects from 8 electrodes around the eyes with Pz as the reference while performing 5°,10°,20°,30° and 40° horizontal saccedes to visual targets. SP peak latencywas measured from SP onset to SP peak on averaged data aligned on SP peak.Re,Its. Significant main effects on SP peak latency are found for saccade size (P0. 05). No significant main effect on SP peak htency is found for eye (P>0. 05). SP peak latency increases with increasing saccade size from 5° to 40°. SP peak latency is longer with saccades back to center than away from center, and with abducting saccades than with adducting saccades. SP peak latency differs at the electrode sites with an order from shorter to longer as follows; innercanth° (IC); inferior orbit (IO); outer canthus (OC); superior orbit (SO).Conclusions. The effects on the peak latency of orbital SP can be explained by the saccade dynamic property, volume conduction as weft as physiologic and anatomic factors of the eyes and orbits. The peak latency of orbital SP can be used to reflect the temporal characteristics of ocular motor units controlling saccedic eye movement.

  13. Regulation of Human Cytomegalovirus Transcription in Latency: Beyond the Major Immediate-Early Promoter

    Directory of Open Access Journals (Sweden)

    John Sinclair

    2013-06-01

    Full Text Available Lytic infection of differentiated cell types with human cytomegalovirus (HCMV results in the temporal expression of between 170–200 open reading frames (ORFs. A number of studies have demonstrated the temporal regulation of these ORFs and that this is orchestrated by both viral and cellular mechanisms associated with the co-ordinated recruitment of transcription complexes and, more recently, higher order chromatin structure. Importantly, HCMV, like all herpes viruses, establishes a lifelong latent infection of the host—one major site of latency being the undifferentiated haematopoietic progenitor cells resident in the bone marrow. Crucially, the establishment of latency is concomitant with the recruitment of cellular enzymes that promote extensive methylation of histones bound to the major immediate early promoter. As such, the repressive chromatin structure formed at the major immediate early promoter (MIEP elicits inhibition of IE gene expression and is a major factor involved in maintenance of HCMV latency. However, it is becoming increasingly clear that a distinct subset of viral genes is also expressed during latency. In this review, we will discuss the mechanisms that control the expression of these latency-associated transcripts and illustrate that regulation of these latency-associated promoters is also subject to chromatin mediated regulation and that the instructive observations previously reported regarding the negative regulation of the MIEP during latency are paralleled in the regulation of latent gene expression.

  14. ABSOLUTE STABILITY OF GENERAL LURIE TYPE INDIRECT CONTROL SYSTEMS

    Institute of Scientific and Technical Information of China (English)

    甘作新; 葛渭高; 赵素霞; 仵永先

    2001-01-01

    In this paper, by introducing a new concept of absolute stability for a certain argument, necessary and sufficient conditions for absolute stability of general Lurie indirect control systems are obtained, and some practical sufficient conditions are also given.

  15. Absolute Orientation Based on Distance Kernel Functions

    Directory of Open Access Journals (Sweden)

    Yanbiao Sun

    2016-03-01

    Full Text Available The classical absolute orientation method is capable of transforming tie points (TPs from a local coordinate system to a global (geodetic coordinate system. The method is based only on a unique set of similarity transformation parameters estimated by minimizing the total difference between all ground control points (GCPs and the fitted points. Nevertheless, it often yields a transformation with poor accuracy, especially in large-scale study cases. To address this problem, this study proposes a novel absolute orientation method based on distance kernel functions, in which various sets of similarity transformation parameters instead of only one set are calculated. When estimating the similarity transformation parameters for TPs using the iterative solution of a non-linear least squares problem, we assigned larger weighting matrices for the GCPs for which the distances from the point are short. The weighting matrices can be evaluated using the distance kernel function as a function of the distances between the GCPs and the TPs. Furthermore, we used the exponential function and the Gaussian function to describe distance kernel functions in this study. To validate and verify the proposed method, six synthetic and two real datasets were tested. The accuracy was significantly improved by the proposed method when compared to the classical method, although a higher computational complexity is experienced.

  16. Absolute stereochemistry of altersolanol A and alterporriols.

    Science.gov (United States)

    Kanamaru, Saki; Honma, Miho; Murakami, Takanori; Tsushima, Taro; Kudo, Shinji; Tanaka, Kazuaki; Nihei, Ken-Ichi; Nehira, Tatsuo; Hashimoto, Masaru

    2012-02-01

    The absolute stereochemistry of altersolanol A (1) was established by observing a positive exciton couplet in the circular dichroism (CD) spectrum of the C3,C4-O-bis(2-naphthoyl) derivative 10 and by chemical correlations with known compound 8. Before the discussion, the relative stereochemistry of 1 was confirmed by X-ray crystallographic analysis. The shielding effect at C7'-OMe group by C1-O-benzoylation established the relative stereochemical relationship between the C8-C8' axial bonding and the C1-C4/C1'-C4' polyol moieties of alterporriols E (3), an atropisomer of the C8-C8' dimer of 1. As 3 could be obtained by dimerization of 1 in vitro, the absolute configuration of its central chirality elements (C1-C4) must be identical to those of 1. Spectral comparison between the experimental and theoretical CD spectra supported the above conclusion. Axial stereochemistry of novel C4-O-deoxy dimeric derivatives, alterporriols F (4) and G (5), were also revealed by comparison of their CD spectra to those of 2 and 3.

  17. Absolute Electron Extraction Efficiency of Liquid Xenon

    Science.gov (United States)

    Kamdin, Katayun; Mizrachi, Eli; Morad, James; Sorensen, Peter

    2016-03-01

    Dual phase liquid/gas xenon time projection chambers (TPCs) currently set the world's most sensitive limits on weakly interacting massive particles (WIMPs), a favored dark matter candidate. These detectors rely on extracting electrons from liquid xenon into gaseous xenon, where they produce proportional scintillation. The proportional scintillation from the extracted electrons serves to internally amplify the WIMP signal; even a single extracted electron is detectable. Credible dark matter searches can proceed with electron extraction efficiency (EEE) lower than 100%. However, electrons systematically left at the liquid/gas boundary are a concern. Possible effects include spontaneous single or multi-electron proportional scintillation signals in the gas, or charging of the liquid/gas interface or detector materials. Understanding EEE is consequently a serious concern for this class of rare event search detectors. Previous EEE measurements have mostly been relative, not absolute, assuming efficiency plateaus at 100%. I will present an absolute EEE measurement with a small liquid/gas xenon TPC test bed located at Lawrence Berkeley National Laboratory.

  18. Orientation-reversal VEP: comparison of phase and peak latencies in adults and infants.

    Science.gov (United States)

    Lee, Jin; Birtles, Deirdre; Wattam-Bell, John; Atkinson, Janette; Braddick, Oliver

    2012-06-15

    The peak latency of pattern-reversal (PR)-VEP has been found to develop rapidly, reaching the adult level around 15 weeks of age. However, the development of orientation-reversal (OR)-VEP, reflecting the specific spatial organization of cortical receptive fields, still remains unknown. OR-VEP was tested in 81 adults at 1-12 reversals/sec (r/s) and 94 infants (age 4-79 weeks) at 2-8r/s. OR data at 4r/s from an additional 123 infants (age 4.0-20.3 weeks) studied previously were also analyzed. In addition to peak transient latencies at 1-4r/s, latency values derived from the gradient of phase against temporal frequency in steady-state recording were also calculated. For both adults and infants, no significant latency differences in the initial positive peaks were found among the low reversal rates. The calculated latency was statistically longer than the transient latency in both groups. While the transient latency asymptoted to adult value of 102 ms at around 50 weeks of age, the calculated latency, unlike that for PR-VEP, showed little variation across the age span. The data suggest a dominant effect of transmission delay on the initial peak in infancy, which reduces with age. However, the overall timing of the cortical response to orientation change remains slower than for pattern reversal in the fully developed visual cortex. Upon reaching maturity, the latencies of the initial positive peak in both pattern and orientation VEPs may arise from the same level of cortical processing in V1, but the overall time course reflected in the steady-state phase continues to show a much more prolonged response to orientation change than the transmission delay seen in the transient VEPs.

  19. Low-Latency Science Exploration of Planetary Bodies: How ISS Might Be Used as Part of a Low-Latency Analog Campaign for Human Exploration

    Science.gov (United States)

    Thronson, Harley; Valinia, Azita; Bleacher, Jacob; Eigenbrode, Jennifer; Garvin, Jim; Petro, Noah

    2014-01-01

    We suggest that the International Space Station be used to examine the application and validation of low-latency telepresence for surface exploration from space as an alternative, precursor, or potentially as an adjunct to astronaut "boots on the ground." To this end, controlled experiments that build upon and complement ground-based analog field studies will be critical for assessing the effects of different latencies (0 to 500 milliseconds), task complexity, and alternate forms of feedback to the operator. These experiments serve as an example of a pathfinder for NASA's roadmap of missions to Mars with low-latency telerobotic exploration as a precursor to astronaut's landing on the surface to conduct geological tasks.

  20. Global dynamics of a vector-borne disease model with latency and saturating incidence rate

    Directory of Open Access Journals (Sweden)

    Ashrafur Rahman

    2014-06-01

    Full Text Available This paper deals with a vector-borne disease model containing latency and nonlinear incidence rates. Global analysis is completely determined by suitable Lyapunov functionals. We explicitely determine the basic reproduction number and find that if this number is less than one then disease dies out, but if the number is larger than one, the disease causing strain become endemic. The study shows that the latency delay explicitely in°uence the disease persistence. Keywords: Latency, saturating incidence, basic reproduction number, global attractivity, Lyapunov functionals.

  1. Latency Analysis of Systems with Multiple Interfaces for Ultra-Reliable M2M Communication

    DEFF Research Database (Denmark)

    Nielsen, Jimmy Jessen; Popovski, Petar

    2016-01-01

    One of the ways to satisfy the requirements of ultra-reliable low latency communication for mission critical Machine-type Communications (MTC) applications is to integrate multiple communication interfaces. In order to estimate the performance in terms of latency and reliability...... of such an integrated communication system, we propose an analysis framework that combines traditional reliability models with technology-specific latency probability distributions. In our proposed model we demonstrate how failure correlation between technologies can be taken into account. We show for the considered...

  2. Latency and Jitter Analysis for IEEE 802.11e Wireless LANs

    Directory of Open Access Journals (Sweden)

    Sungkwan Youm

    2013-01-01

    Full Text Available This paper presents a numerical analysis of latency and jitter for IEEE 802.11e wireless local area networks (WLANs in a saturation condition, by using a Markov model. We use this model to explicate how the enhanced distributed coordination function (EDCF differentiates classes of service and to characterize the probability distribution of the medium access control (MAC layer packet latency and jitter, on which the quality of the voice over Internet protocol (VoIP calls is dependent. From the proposed analytic model, we can estimate the available number of nodes determining the system performance, in order to satisfy user demands on the latency and jitter.

  3. A Conceptual Approach to Absolute Value Equations and Inequalities

    Science.gov (United States)

    Ellis, Mark W.; Bryson, Janet L.

    2011-01-01

    The absolute value learning objective in high school mathematics requires students to solve far more complex absolute value equations and inequalities. When absolute value problems become more complex, students often do not have sufficient conceptual understanding to make any sense of what is happening mathematically. The authors suggest that the…

  4. Invariant and Absolute Invariant Means of Double Sequences

    Directory of Open Access Journals (Sweden)

    Abdullah Alotaibi

    2012-01-01

    Full Text Available We examine some properties of the invariant mean, define the concepts of strong σ-convergence and absolute σ-convergence for double sequences, and determine the associated sublinear functionals. We also define the absolute invariant mean through which the space of absolutely σ-convergent double sequences is characterized.

  5. Plasma Assisted Combustion

    Science.gov (United States)

    2007-02-28

    pressure hydrogen is given in Fig. 2.14. The regions typical for “common” glow discharges (negative glow, Faraday dark space, and positive column) are...Hollenstein Ch. Plasma Phys. Control. Fusion, 42 (2000) 93. [107] M.A. Heald and C.B. Wahrton, Plasma diagnostics with microwaves, John Wi- ley &Sons, New York...Nitrous Oxide J. Chem. Soc. Faraday Trans. 69 352 [194] Albers E A, Hoyermann K, Schacke H, Schmatjko K J, Wagner H Gg, Wolfrum J 1975 Absolute Rate

  6. Use of Absolute and Comparative Performance Feedback in Absolute and Comparative Judgments and Decisions

    Science.gov (United States)

    Moore, Don A.; Klein, William M. P.

    2008-01-01

    Which matters more--beliefs about absolute ability or ability relative to others? This study set out to compare the effects of such beliefs on satisfaction with performance, self-evaluations, and bets on future performance. In Experiment 1, undergraduate participants were told they had answered 20% correct, 80% correct, or were not given their…

  7. Use of Absolute and Comparative Performance Feedback in Absolute and Comparative Judgments and Decisions

    Science.gov (United States)

    Moore, Don A.; Klein, William M. P.

    2008-01-01

    Which matters more--beliefs about absolute ability or ability relative to others? This study set out to compare the effects of such beliefs on satisfaction with performance, self-evaluations, and bets on future performance. In Experiment 1, undergraduate participants were told they had answered 20% correct, 80% correct, or were not given their…

  8. How is an absolute democracy possible?

    Directory of Open Access Journals (Sweden)

    Joanna Bednarek

    2011-01-01

    Full Text Available In the last part of the Empire trilogy, Commonwealth, Negri and Hardt ask about the possibility of the self-governance of the multitude. When answering, they argue that absolute democracy, understood as the political articulation of the multitude that does not entail its unification (construction of the people is possible. As Negri states, this way of thinking about political articulation is rooted in the tradition of democratic materialism and constitutes the alternative to the dominant current of modern political philosophy that identifies political power with sovereignty. The multitude organizes itself politically by means of the constitutive power, identical with the ontological creativity or productivity of the multitude. To state the problem of political organization means to state the problem of class composition: political democracy is at the same time economic democracy.

  9. Absolute geostrophic currents in global tropical oceans

    Science.gov (United States)

    Yang, Lina; Yuan, Dongliang

    2016-11-01

    A set of absolute geostrophic current (AGC) data for the period January 2004 to December 2012 are calculated using the P-vector method based on monthly gridded Argo profiles in the world tropical oceans. The AGCs agree well with altimeter geostrophic currents, Ocean Surface Current Analysis-Real time currents, and moored current-meter measurements at 10-m depth, based on which the classical Sverdrup circulation theory is evaluated. Calculations have shown that errors of wind stress calculation, AGC transport, and depth ranges of vertical integration cannot explain non-Sverdrup transport, which is mainly in the subtropical western ocean basins and equatorial currents near the Equator in each ocean basin (except the North Indian Ocean, where the circulation is dominated by monsoons). The identified non-Sverdrup transport is thereby robust and attributed to the joint effect of baroclinicity and relief of the bottom (JEBAR) and mesoscale eddy nonlinearity.

  10. Variance computations for functional of absolute risk estimates.

    Science.gov (United States)

    Pfeiffer, R M; Petracci, E

    2011-07-01

    We present a simple influence function based approach to compute the variances of estimates of absolute risk and functions of absolute risk. We apply this approach to criteria that assess the impact of changes in the risk factor distribution on absolute risk for an individual and at the population level. As an illustration we use an absolute risk prediction model for breast cancer that includes modifiable risk factors in addition to standard breast cancer risk factors. Influence function based variance estimates for absolute risk and the criteria are compared to bootstrap variance estimates.

  11. WHY DOES LEIBNIZ NEED ABSOLUTE TIME?

    Directory of Open Access Journals (Sweden)

    NICOLÁS VAUGHAN C.

    2007-08-01

    Full Text Available Resumen: En este ensayo pongo en contraposición dos doctrinas conspicuamenteleibnicianas: la doctrina del tiempo relacional e ideal, y la doctrina de la armonía preestablecida. Argumentaré que si todas las substancias están necesariamentecoordinadas, entonces no tiene sentido negar el carácter absoluto y real del tiempo. En la primera sección describiré la concepción newtoniana y clarkeana del tiempo absoluto; en la segunda discutiré la crítica leibniciana a dicha concepción, crítica sobre la que se erige su doctrina relacional e ideal del tiempo; en la tercera sección daré un vistazo a la metafísica monádica madura de Leibniz, haciendo especial énfasis en la doctrina de la armonía preestablecida; finalmente, en la última sección sugeriré la existencia de una tensión irreconciliable entre estas dos doctrinas.Abstract: In this paper I bring together two characteristically Leibnizean doctrines:the doctrine of relational and ideal time, and the doctrine of preestablished harmony. I will argue that, if every substance is necessarily connected with another, then it makes no sense to deny absolute and real time. In the first section, I will describe Newton’s and Clarke’s conception of absolute time; then, in the second section, I will consider Leibniz’s critique of that conception, on which he bases his ideal and relational doctrine of time. In the third section I will look briefly at Leibniz’s mature monadic metaphysics, taking special account of his doctrine of preestablished harmony. In the last section, I will suggest that there is an irreconcilable tension between these two doctrines.

  12. Bifurcated method and apparatus for floating point addition with decreased latency time

    Energy Technology Data Exchange (ETDEWEB)

    Farmwald, Paul M. (Livermore, CA)

    1987-01-01

    Apparatus for decreasing the latency time associated with floating point addition and subtraction in a computer, using a novel bifurcated, pre-normalization/post-normalization approach that distinguishes between differences of floating point exponents.

  13. Judgment and judgment latency for freedom and responsibility relatedness as a function of subtle linguistic variations.

    Science.gov (United States)

    Wilkerson, Keith; McGahan, Joseph R; Stevens, Rick; Williamson, David; Low, Jean

    2009-12-01

    The goal of this study was to determine whether differential response formats to covariation problems influence corresponding response latencies. The authors provided participants with 3 trials of 16 statements addressing positive and negative relations between freedom and responsibility. The authors framed half of the items around responsibility given freedom and the other half around freedom given responsibility. Response formats comprised true-false, agree-disagree, and yes-no answers as a between-participants factor. Results indicated that the manipulation of response format did not affect latencies. However, latencies differed according to the framing of the items. For items framed around freedom given responsibility, latencies were shorter. In addition, participants were more likely to report a positive relation between freedom and responsibility when items were framed around freedom given responsibility. The authors discuss implications relative to previous research in this area and give recommendations for future research.

  14. Improving IEEE 802.15.4 for Low-Latency Energy-Efficient Industrial Applications

    Science.gov (United States)

    Chen, Feng

    The IEEE 802.15.4 standard for LR-WPAXs is becoming a de-facto standard for Wireless Sensor Xetworks (WSXs) applications in industrial fields. In this paper, we evaluate the latency performance of the IEEE 802.15.4 protocol based on a typical industrial scenario: a star network with 20 devices that send short messages (1 Byte) to the PAX coordinator. We analyzed the behavior of the GTS mechanism in the standard analytically. The results reveal essential limitations of the standard for low-latency applications in automation environments. According to our findings, we propose an enhanced protocol version that fully supports industry demands on low-latency communication. Our protocol version uses the original physical layer and, thus, can be implemented conveniently using cheap IEEE 802.15.4 hardware. The analytical results prove that we are able to meet the guaranteed low latency of 10 ms as specified by typical automation environments.

  15. Ocular herpes simplex virus: how are latency, reactivation, recurrent disease and therapy interrelated?

    Science.gov (United States)

    Al-Dujaili, Lena J; Clerkin, Patrick P; Clement, Christian; McFerrin, Harris E; Bhattacharjee, Partha S; Varnell, Emily D; Kaufman, Herbert E; Hill, James M

    2012-01-01

    Most humans are infected with herpes simplex virus (HSV) type 1 in early childhood and remain latently infected throughout life. While most individuals have mild or no symptoms, some will develop destructive HSV keratitis. Ocular infection with HSV-1 and its associated sequelae account for the majority of corneal blindness in industrialized nations. Neuronal latency in the peripheral ganglia is established when transcription of the viral genome is repressed (silenced) except for the latency-associated transcripts and microRNAs. The functions of latency-associated transcripts have been investigated since 1987. Roles have been suggested relating to reactivation, establishment of latency, neuronal protection, antiapoptosis, apoptosis, virulence and asymptomatic shedding. Here, we review HSV-1 latent infections, reactivation, recurrent disease and antiviral therapies for the ocular HSV diseases. PMID:21861620

  16. Industrial WSN Based on IR-UWB and a Low-Latency MAC Protocol

    Science.gov (United States)

    Reinhold, Rafael; Underberg, Lisa; Wulf, Armin; Kays, Ruediger

    2016-07-01

    Wireless sensor networks for industrial communication require high reliability and low latency. As current wireless sensor networks do not entirely meet these requirements, novel system approaches need to be developed. Since ultra wideband communication systems seem to be a promising approach, this paper evaluates the performance of the IEEE 802.15.4 impulse-radio ultra-wideband physical layer and the IEEE 802.15.4 Low Latency Deterministic Network (LLDN) MAC for industrial applications. Novel approaches and system adaptions are proposed to meet the application requirements. In this regard, a synchronization approach based on circular average magnitude difference functions (CAMDF) and on a clean template (CT) is presented for the correlation receiver. An adapted MAC protocol titled aggregated low latency (ALL) MAC is proposed to significantly reduce the resulting latency. Based on the system proposals, a hardware prototype has been developed, which proves the feasibility of the system and visualizes the real-time performance of the MAC protocol.

  17. Neuronal IFN signaling is dispensable for the establishment of HSV-1 latency.

    Science.gov (United States)

    Rosato, Pamela C; Katzenell, Sarah; Pesola, Jean M; North, Brian; Coen, Donald M; Leib, David A

    2016-10-01

    IFN responses control acute HSV infection, but their role in regulating HSV latency is poorly understood. To address this we used mice lacking IFN signaling specifically in neural tissues. These mice supported a higher acute viral load in nervous tissue and delayed establishment of latency. While latent HSV-1 genome copies were equivalent, ganglia from neuronal IFN signaling-deficient mice unexpectedly supported reduced reactivation. IFNβ promoted survival of primary sensory neurons after infection with HSV-1, indicating a role for IFN signaling in sustaining neurons. We observed higher levels of latency associated transcripts (LATs) per HSV genome in mice lacking neuronal IFN signaling, consistent with a role for IFN in regulating LAT expression. These data show that neuronal IFN signaling modulates the expression of LAT and may conserve the pool of neurons available to harbor latent HSV-1 genome. The data also show that neuronal IFN signaling is dispensable for the establishment of latency.

  18. Kleine-levin syndrome: clinical course, polysomnography and multiple sleep latency test. Case report

    Directory of Open Access Journals (Sweden)

    REIMÃO RUBENS

    1998-01-01

    Full Text Available A case of Kleine-Levin syndrome, with chronic severe periodic hypersomnia is described in a 17-year-old female. The first episode started when she was 15 years old. The episodes were characterized by periodic hypersomnia accompanied by hyperphagia, lasting 5 days, and repeating at 28 to 60 day intervals. The severity of hypersomnia prevented her from attending school activities. Outside the hypersomnia periods, she was asymptomatic. EEG, brain computerized tomography and brain nuclear magnetic resonance were normal; all-night polysomnography, Multiple Sleep Latency Test (MSLT and Epworth Sleepiness Scale (ESS were within normal limits. During the period of hypersomnolence, polysomnography showed short sleep latency and short REM latency. MSLT mean sleep latency was 1.8 min; and REM period was present in one subtest; the ESS was markedly elevated.

  19. Rein: Taming Tail Latency in Key-Value Stores via Multiget Scheduling

    KAUST Repository

    Reda, Waleed

    2017-04-17

    We tackle the problem of reducing tail latencies in distributed key-value stores, such as the popular Cassandra database.We focus on workloads of multiget requests, which batch together access to several data elements and parallelize read operations across the data store machines. We first analyze a production trace of a real system and quantify the skew due to multiget sizes, key popularity, and other factors. We then proceed to identify opportunities for reduction of tail latencies by recognizing the composition of aggregate requests and by carefully scheduling bottleneck operations that can otherwise create excessive queues. We design and implement a system called Rein, which reduces latency via inter-multiget scheduling using low overhead techniques. We extensively evaluate Rein via experiments in Amazon Web Services (AWS) and simulations. Our scheduling algorithms reduce the median, 95, and 99 percentile latencies by factors of 1.5, 1.5, and 1.9, respectively.

  20. Research on low-latency MAC protocols for wireless sensor networks

    Science.gov (United States)

    He, Chenguang; Sha, Xuejun; Lee, Chankil

    2007-11-01

    Energy-efficient should not be the only design goal in MAC protocols for wireless sensor networks, which involve the use of battery-operated computing and sensing devices. Low-latency operation becomes the same important as energy-efficient in the case that the traffic load is very heavy or the real-time constrain is used in applications like tracking or locating. This paper introduces some causes of traditional time delays which are inherent in a multi-hops network using existing WSN MAC protocols, illuminates the importance of low-latency MAC design for wireless sensor networks, and presents three MACs as examples of low-latency protocols designed specially for sleep delay, wait delay and wakeup delay in wireless sensor networks, respectively. The paper also discusses design trade-offs with emphasis on low-latency and points out their advantages and disadvantages, together with some design considerations and suggestions for MAC protocols for future applications and researches.

  1. Measurement and reduction of system latency in see-through helmet mounted display (HMD) systems

    Science.gov (United States)

    Vincenzi, Dennis A.; Deaton, John E.; Blickenderfer, Elizabeth L.; Pray, Rick; Williams, Barry; Buker, Timothy J.

    2010-04-01

    Future military aviation platforms such as the proposed Joint Strike Fighter F-35 will integrate helmet mounted displays (HMDs) with the avionics and weapon systems to the degree that the HMDs will become the aircraft's primary display system. In turn, training of pilot flight skills using HMDs will be essential in future training systems. In order to train these skills using simulation based training, improvements must be made in the integration of HMDs with out-thewindow (OTW) simulations. Currently, problems such as latency contribute to the onset of simulator sickness and provide distractions during training with HMD simulator systems that degrade the training experience. Previous research has used Kalman predictive filters as a means of mitigating the system latency present in these systems. While this approach has yielded some success, more work is needed to develop innovative and improved strategies that reduce system latency as well as to include data collected from the user perspective as a measured variable during test and evaluation of latency reduction strategies. The purpose of this paper is twofold. First, the paper describes a new method to measure and assess system latency from the user perspective. Second, the paper describes use of the testbed to examine the efficacy of an innovative strategy that combines a customized Kalman filter with a neural network approach to mitigate system latency. Results indicate that the combined approach reduced system latency significantly when compared to baseline data and the traditional Kalman filter. Reduced latency errors should mitigate the onset of simulator sickness and ease simulator sickness symptomology. Implications for training systems will be discussed.

  2. Advanced techniques for the analysis of crisis stability, deterrence, and latency

    Energy Technology Data Exchange (ETDEWEB)

    Canavan, G.H.

    1997-12-01

    Studies on crisis stability, deterrence, and latency are presented in chronological order, which also reflects their logical order of development, captures the main features of stability analysis; relates first strike, crisis, and arms control stability as seen from US and Russian perspective; and addresses questions such as whether uncertainty in damage preference or defense deployment can be destabilizing. It illustrates the problems with alternative metrics, latency and reconstitution, and deep unilateral and proportional force reductions.

  3. Reducing audio stimulus presentation latencies across studies, laboratories, and hardware and operating system configurations.

    Science.gov (United States)

    Babjack, Destiny L; Cernicky, Brandon; Sobotka, Andrew J; Basler, Lee; Struthers, Devon; Kisic, Richard; Barone, Kimberly; Zuccolotto, Anthony P

    2015-09-01

    Using differing computer platforms and audio output devices to deliver audio stimuli often introduces (1) substantial variability across labs and (2) variable time between the intended and actual sound delivery (the sound onset latency). Fast, accurate audio onset latencies are particularly important when audio stimuli need to be delivered precisely as part of studies that depend on accurate timing (e.g., electroencephalographic, event-related potential, or multimodal studies), or in multisite studies in which standardization and strict control over the computer platforms used is not feasible. This research describes the variability introduced by using differing configurations and introduces a novel approach to minimizing audio sound latency and variability. A stimulus presentation and latency assessment approach is presented using E-Prime and Chronos (a new multifunction, USB-based data presentation and collection device). The present approach reliably delivers audio stimuli with low latencies that vary by ≤1 ms, independent of hardware and Windows operating system (OS)/driver combinations. The Chronos audio subsystem adopts a buffering, aborting, querying, and remixing approach to the delivery of audio, to achieve a consistent 1-ms sound onset latency for single-sound delivery, and precise delivery of multiple sounds that achieves standard deviations of 1/10th of a millisecond without the use of advanced scripting. Chronos's sound onset latencies are small, reliable, and consistent across systems. Testing of standard audio delivery devices and configurations highlights the need for careful attention to consistency between labs, experiments, and multiple study sites in their hardware choices, OS selections, and adoption of audio delivery systems designed to sidestep the audio latency variability issue.

  4. Long-latency auditory evoked potentials with verbal and nonverbal stimuli.

    Science.gov (United States)

    Oppitz, Sheila Jacques; Didoné, Dayane Domeneghini; Silva, Débora Durigon da; Gois, Marjana; Folgearini, Jordana; Ferreira, Geise Corrêa; Garcia, Michele Vargas

    2015-01-01

    Long-latency auditory evoked potentials represent the cortical activity related to attention, memory, and auditory discrimination skills. Acoustic signal processing occurs differently between verbal and nonverbal stimuli, influencing the latency and amplitude patterns. To describe the latencies of the cortical potentials P1, N1, P2, N2, and P3, as well as P3 amplitude, with different speech stimuli and tone bursts, and to classify them in the presence and absence of these data. A total of 30 subjects with normal hearing were assessed, aged 18-32 years old, matched by gender. Nonverbal stimuli were used (tone burst; 1000Hz - frequent and 4000Hz - rare); and verbal (/ba/ - frequent; /ga/, /da/, and /di/ - rare). Considering the component N2 for tone burst, the lowest latency found was 217.45ms for the BA/DI stimulus; the highest latency found was 256.5ms. For the P3 component, the shortest latency with tone burst stimuli was 298.7 with BA/GA stimuli, the highest, was 340ms. For the P3 amplitude, there was no statistically significant difference among the different stimuli. For latencies of components P1, N1, P2, N2, P3, there were no statistical differences among them, regardless of the stimuli used. There was a difference in the latency of potentials N2 and P3 among the stimuli employed but no difference was observed for the P3 amplitude. Copyright © 2015 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  5. Self-esteem modulates the latency of P2 component in implicit self-relevant processing.

    Science.gov (United States)

    Yang, Juan; Qi, Mingming; Guan, Lili

    2014-03-01

    Previous study has shown that the latency of P2 component was more prolonged in processing self-relevant words compared to processing non-self-relevant words. However, the prolonged P2 latency may index the self-relevance of the words, the valence of the words, or an interaction of the two. The present study aimed to (1) further clarify the specific psychological significance of the prolonged P2 latency in implicit self-processing and (2) investigate the potential association between self-esteem and the latency of P2 in processing implicit self-relevant information. Nineteen participants were examined using event-related potentials (ERPs) technology. They were exposed to positive and negative words and were asked to make a judgment about the color of each word. For the data analysis, words were grouped individually according to their degree of self-relevance (low vs. high) for each participant. Results showed that the latency of P2 was more prolonged in processing the negative-high self-relevant words compared to processing the positive-high self-relevant words. Also, self-esteem was negatively correlated with the P2 latency in processing negative-high self-relevant words. Overall, the results of the present study suggested that levels of self-esteem might modulate neural correlates of self-referential processing.

  6. Photosensor-Based Latency Measurement System for Head-Mounted Displays

    Directory of Open Access Journals (Sweden)

    Min-Woo Seo

    2017-05-01

    Full Text Available In this paper, a photosensor-based latency measurement system for head-mounted displays (HMDs is proposed. The motion-to-photon latency is the greatest reason for motion sickness and dizziness felt by users when wearing an HMD system. Therefore, a measurement system is required to accurately measure and analyze the latency to reduce these problems. The existing measurement system does not consider the actual physical movement in humans, and its accuracy is also very low. However, the proposed system considers the physical head movement and is highly accurate. Specifically, it consists of a head position model-based rotary platform, pixel luminance change detector, and signal analysis and calculation modules. Using these modules, the proposed system can exactly measure the latency, which is the time difference between the physical movement for a user and the luminance change of an output image. In the experiment using a commercial HMD, the latency was measured to be up to 47.05 ms. In addition, the measured latency increased up to 381.17 ms when increasing the rendering workload in the HMD.

  7. Clinical value of ipsi- and contralateral sacral reflex latency measurement: a normative data study in man.

    Science.gov (United States)

    Amarenco, G; Kerdraon, J

    2000-01-01

    The latency of the bulbocavernosus reflex (BCR) evoked by electrical stimulation of the penis provides a measure of the conduction velocity over the sacral reflex arc at the S2-4 level but does not allow evaluation of the side affected since it results from the simultaneous excitation of both dorsal nerves of the penis (DNP) at the penile root. To evaluate the reliability of the side-to-side BCR latency measurement, this study compared the reflex characteristics of the response elicited by both DNP stimulation and unilateral DNP block. After a unilateral selective DNP anesthesic block, we found that the early response of the contralateral BCR is strictly ipsilateral with no differences in terms of latency, morphology, and reflex threshold from controls. This result may indicate that the side-to-side BCR latency measurement allows a comparative study of the respective right and left sacral reflex arcs in men. We found a mean inter-latency difference of 1.8 +/- 0.4 millisecond of the early BCR response after simultaneous recording of the right and left sides in 10 normal men. We established that an inter-latency difference >3 milliseconds may be indicative of a significant alteration in the conduction over the sacral reflex arc.

  8. Generation of spike latency tuning by thalamocortical circuits in auditory cortex.

    Science.gov (United States)

    Zhou, Yi; Mesik, Lukas; Sun, Yujiao J; Liang, Feixue; Xiao, Zhongju; Tao, Huizhong W; Zhang, Li I

    2012-07-18

    In many sensory systems, the latency of spike responses of individual neurons is found to be tuned for stimulus features and proposed to be used as a coding strategy. Whether the spike latency tuning is simply relayed along sensory ascending pathways or generated by local circuits remains unclear. Here, in vivo whole-cell recordings from rat auditory cortical neurons in layer 4 revealed that the onset latency of their aggregate thalamic input exhibited nearly flat tuning for sound frequency, whereas their spike latency tuning was much sharper with a broadly expanded dynamic range. This suggests that the spike latency tuning is not simply inherited from the thalamus, but can be largely reconstructed by local circuits in the cortex. Dissecting of thalamocortical circuits and neural modeling further revealed that broadly tuned intracortical inhibition prolongs the integration time for spike generation preferentially at off-optimal frequencies, while sharply tuned intracortical excitation shortens it selectively at the optimal frequency. Such push and pull mechanisms mediated likely by feedforward excitatory and inhibitory inputs respectively greatly sharpen the spike latency tuning and expand its dynamic range. The modulation of integration time by thalamocortical-like circuits may represent an efficient strategy for converting information spatially coded in synaptic strength to temporal representation.

  9. Long-latency reflexes account for limb biomechanics through several supraspinal pathways

    Directory of Open Access Journals (Sweden)

    Isaac Louis Kurtzer

    2015-01-01

    Full Text Available Accurate control of body posture is enforced by a multitude of corrective actions operating over a range of time scales. The earliest correction is the short-latency reflex which occurs between 20-45 ms following a sudden displacement of the limb and is generated entirely by spinal circuits. In contrast, voluntary reactions are generated by a highly distributed network but at a significantly longer delay after stimulus onset (greater than 100 ms. Between these two epochs is the long-latency reflex (around 50-100 ms which but acts more rapidly than of voluntary reactions but shares some supraspinal pathways and functional capabilities. In particular, the long-latency reflex accounts for the arm’s biomechanical properties rather than only responding to local muscle stretch like the short-latency reflex. This paper will review how the long-latency reflex accounts for the arm’s biomechanical properties and the supraspinal pathways supporting this ability. Relevant experimental paradigms include clinical studies, non-invasive brain stimulation, neural recordings in monkeys, and human behavioral studies. The sum of this effort indicates that primary motor cortex and reticular formation contribute to the the long-latency reflex either by generating or scaling its structured response appropriate for the arm’s biomechanics whereas the cerebellum scales the magnitude of the feedback response. Additional putative pathways are discussed as well as potential research lines.

  10. Temporal processing and long-latency auditory evoked potential in stutterers.

    Science.gov (United States)

    Prestes, Raquel; de Andrade, Adriana Neves; Santos, Renata Beatriz Fernandes; Marangoni, Andrea Tortosa; Schiefer, Ana Maria; Gil, Daniela

    Stuttering is a speech fluency disorder, and may be associated with neuroaudiological factors linked to central auditory processing, including changes in auditory processing skills and temporal resolution. To characterize the temporal processing and long-latency auditory evoked potential in stutterers and to compare them with non-stutterers. The study included 41 right-handed subjects, aged 18-46 years, divided into two groups: stutterers (n=20) and non-stutters (n=21), compared according to age, education, and sex. All subjects were submitted to the duration pattern tests, random gap detection test, and long-latency auditory evoked potential. Individuals who stutter showed poorer performance on Duration Pattern and Random Gap Detection tests when compared with fluent individuals. In the long-latency auditory evoked potential, there was a difference in the latency of N2 and P3 components; stutterers had higher latency values. Stutterers have poor performance in temporal processing and higher latency values for N2 and P3 components. Copyright © 2017 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  11. Low-Latency Lunar Surface Telerobotics from Earth-Moon Libration Points

    Science.gov (United States)

    Lester, Daniel; Thronson, Harley

    2011-01-01

    Concepts for a long-duration habitat at Earth-Moon LI or L2 have been advanced for a number of purposes. We propose here that such a facility could also have an important role for low-latency telerobotic control of lunar surface equipment, both for lunar science and development. With distances of about 60,000 km from the lunar surface, such sites offer light-time limited two-way control latencies of order 400 ms, making telerobotic control for those sites close to real time as perceived by a human operator. We point out that even for transcontinental teleoperated surgical procedures, which require operational precision and highly dexterous manipulation, control latencies of this order are considered adequate. Terrestrial telerobots that are used routinely for mining and manufacturing also involve control latencies of order several hundred milliseconds. For this reason, an Earth-Moon LI or L2 control node could build on the technology and experience base of commercially proven terrestrial ventures. A lunar libration-point telerobotic node could demonstrate exploration strategies that would eventually be used on Mars, and many other less hospitable destinations in the solar system. Libration-point telepresence for the Moon contrasts with lunar telerobotic control from the Earth, for which two-way control latencies are at least six times longer. For control latencies that long, telerobotic control efforts are of the "move-and-wait" variety, which is cognitively inferior to near real-time control.

  12. Measurements of Absolute Abundances in Solar Flares

    CERN Document Server

    Warren, Harry P

    2013-01-01

    We present measurements of elemental abundances in solar flares with the EUV Variability Experiment (EVE) on the Solar Dynamics Observatory (SDO). EVE observes both high temperature Fe emission lines (Fe XV-Fe XXIV) and continuum emission from thermal bremsstrahlung that is proportional to the abundance of H. By comparing the relative intensities of line and continuum emission it is possible to determine the enrichment of the flare plasma relative to the composition of the photosphere. This is the first ionization potential or FIP bias ($f$). Since thermal bremsstrahlung at EUV wavelengths is relatively insensitive to the electron temperature, it is important to account for the distribution of electron temperatures in the emitting plasma. We accomplish this by using the observed spectra to infer the differential emission measure distribution and FIP bias simultaneously. In each of the 21 flares that we analyze we find that the observed composition is close to photospheric. The mean FIP bias in our sample is $...

  13. A template-free approach for determining the latency of single events of auditory evoked M100

    Energy Technology Data Exchange (ETDEWEB)

    Burghoff, M [Physikalisch-Technische Bundesanstalt (PTB), Berlin (Germany); Link, A [Physikalisch-Technische Bundesanstalt (PTB), Berlin (Germany); Salajegheh, A [Cognitive Neuroscience of Language Laboratory, University of Maryland College Park, MD (United States); Elster, C [Physikalisch-Technische Bundesanstalt (PTB), Berlin (Germany); Poeppel, D [Cognitive Neuroscience of Language Laboratory, University of Maryland College Park, MD (United States); Trahms, L [Physikalisch-Technische Bundesanstalt (PTB), Berlin (Germany)

    2005-02-07

    The phase of the complex output of a narrow band Gaussian filter is taken to define the latency of the auditory evoked response M100 recorded by magnetoencephalography. It is demonstrated that this definition is consistent with the conventional peak latency. Moreover, it provides a tool for reducing the number of averages needed for a reliable estimation of the latency. Single-event latencies obtained by this procedure can be used to improve the signal quality of the conventional average by latency adjusted averaging. (note)

  14. Absolute Abundance Measurements in Solar Flares

    Science.gov (United States)

    Warren, Harry

    2014-06-01

    We present measurements of elemental abundances in solar flares with EVE/SDO and EIS/Hinode. EVE observes both high temperature Fe emission lines Fe XV-XXIV and continuum emission from thermal bremsstrahlung that is proportional to the abundance of H. By comparing the relative intensities of line and continuum emission it is possible to determine the enrichment of the flare plasma relative to the composition of the photosphere. This is the first ionization potential or FIP bias (F). Since thermal bremsstrahlung at EUV wavelengths is relatively insensitive to the electron temperature it is important to account for the distribution of electron temperatures in the emitting plasma. We accomplish this by using the observed spectra to infer the differential emission measure distribution and FIP bias simultaneously. In each of the 21 flares that we analyze we find that the observed composition is close to photospheric. The mean FIP bias in our sample is F=1.17+-0.22. Furthermore, we have compared the EVE measurements with corresponding flare observations of intermediate temperature S, Ar, Ca, and Fe emission lines taken with EIS. Our initial calculations also indicate a photospheric composition for these observations. This analysis suggests that the bulk of the plasma evaporated during a flare comes from deep in the chromosphere, below the region where elemental fractionation in the non-flaring corona occurs.

  15. Measurements of Absolute Abundances in Solar Flares

    Science.gov (United States)

    Warren, Harry P.

    2014-05-01

    We present measurements of elemental abundances in solar flares with the EUV Variability Experiment (EVE) on the Solar Dynamics Observatory. EVE observes both high temperature Fe emission lines (Fe XV-Fe XXIV) and continuum emission from thermal bremsstrahlung that is proportional to the abundance of H. By comparing the relative intensities of line and continuum emission it is possible to determine the enrichment of the flare plasma relative to the composition of the photosphere. This is the first ionization potential or FIP bias (f). Since thermal bremsstrahlung at EUV wavelengths is relatively insensitive to the electron temperature, it is important to account for the distribution of electron temperatures in the emitting plasma. We accomplish this by using the observed spectra to infer the differential emission measure distribution and FIP bias simultaneously. In each of the 21 flares that we analyze we find that the observed composition is close to photospheric. The mean FIP bias in our sample is f = 1.17 ± 0.22. This analysis suggests that the bulk of the plasma evaporated during a flare comes from deep in the chromosphere, below the region where elemental fractionation occurs.

  16. Electron cyclotron emission measurements on JET: Michelson interferometer, new absolute calibration, and determination of electron temperature.

    Science.gov (United States)

    Schmuck, S; Fessey, J; Gerbaud, T; Alper, B; Beurskens, M N A; de la Luna, E; Sirinelli, A; Zerbini, M

    2012-12-01

    At the fusion experiment JET, a Michelson interferometer is used to measure the spectrum of the electron cyclotron emission in the spectral range 70-500 GHz. The interferometer is absolutely calibrated using the hot/cold technique and, in consequence, the spatial profile of the plasma electron temperature is determined from the measurements. The current state of the interferometer hardware, the calibration setup, and the analysis technique for calibration and plasma operation are described. A new, full-system, absolute calibration employing continuous data acquisition has been performed recently and the calibration method and results are presented. The noise level in the measurement is very low and as a result the electron cyclotron emission spectrum and thus the spatial profile of the electron temperature are determined to within ±5% and in the most relevant region to within ±2%. The new calibration shows that the absolute response of the system has decreased by about 15% compared to that measured previously and possible reasons for this change are presented. Temperature profiles measured with the Michelson interferometer are compared with profiles measured independently using Thomson scattering diagnostics, which have also been recently refurbished and recalibrated, and agreement within experimental uncertainties is obtained.

  17. Color assimilation and contrast near absolute threshold

    Science.gov (United States)

    McCann, John

    2012-01-01

    Simultaneous Contrast and Assimilation test targets are almost always viewed at high light levels. We measured the appearances of Simultaneous Contrast, Assimilation and other spatial surrounds near absolute rod threshold. Given the very different spatial organizations of receptive fields in rod and cone vision at detection threshold, it is not obvious that these familiar cone-vision spatial effects would be observed at rod light levels. Nevertheless, the spatial experiments showed that these targets have the same changes in appearance as those observed in bright light. Our experiments used very dim candle light that was above threshold for rods and L cones, and below threshold for M and S cones. Although detection threshold experiments show very different spatial organizations for rod and cone vision, we found that spatial contrast experiments gave the same changes of appearance. Neural contrast mechanisms at the lowest end of our visual HDR range are very similar to those at the top of the range in sunlight. This is true for both chromatic and achromatic targets.

  18. PROFIT – THE ABSOLUTE EXPRESSION OF PROFITABILITY

    Directory of Open Access Journals (Sweden)

    Daniela SIMTION

    2013-12-01

    Full Text Available Profitability of an economic unit is expressed through a system of indicators, because "no index or economic category can reflect the total, perfect, complex reality of economic phenomena or processes. Each expresses a side of concrete, essential details (indexes, but a full one (economic category. This system of indexes for profitability is characterized by a higher degree of consolidation, of reflection of the economic-financial results. They must be correlated to the other indexes of economic efficiency from the various subsystems that constitute the factors which determine the actual amount of profit and the rate of return. Each indicator has a certain form of expression according to the phenomena to which it refers. Thus, they can be expressed in relative sizes as medium sizes or indexes. They can also be expressed in physical, conventional or value units. The ability to develop monetary results can not be judged independently to the employed means for achieving them. Therefore, the profitability analysis is not limited to investigating its absolute indexes but also the relative ones, obtained by comparing the results to the means employed or consumed for developing the specific activity

  19. Positioning, alignment and absolute pointing of the ANTARES neutrino telescope

    Energy Technology Data Exchange (ETDEWEB)

    Fehr, F [Erlangen Centre for Astroparticle Physics, Erwin-Rommel-Str. 1 (Germany); Distefano, C, E-mail: fehr@physik.uni-erlangen.d [INFN Laboratori Nazional del Sud, Via S. Sofia 62, 95123 Catania (Italy)

    2010-01-01

    A precise detector alignment and absolute pointing is crucial for point-source searches. The ANTARES neutrino telescope utilises an array of hydrophones, tiltmeters and compasses for the relative positioning of the optical sensors. The absolute calibration is accomplished by long-baseline low-frequency triangulation of the acoustic reference devices in the deep-sea with a differential GPS system at the sea surface. The absolute pointing can be independently verified by detecting the shadow of the Moon in cosmic rays.

  20. Absolute quantification of somatic DNA alterations in human cancer

    OpenAIRE

    Carter, Scott L.; Cibulskis, Kristian; Helman, Elena; McKenna, Aaron; Shen, Hui; Zack, Travis; Laird, Peter W.; Onofrio, Robert C.; Winckler, Wendy; Weir, Barbara A; Beroukhim, Rameen; Pellman, David; Levine, Douglas A.; Lander, Eric S.; Meyerson, Matthew

    2012-01-01

    We developed a computational method (ABSOLUTE) that infers tumor purity and malignant cell ploidy directly from analysis of somatic DNA alterations. ABSOLUTE can detect subclonal heterogeneity, somatic homozygosity, and calculate statistical sensitivity to detect specific aberrations. We used ABSOLUTE to analyze ovarian cancer data and identified pervasive subclonal somatic point mutations. In contrast, mutations occurring in key tumor suppressor genes, TP53 and NF1 were predominantly clonal ...

  1. Absolute quantification of somatic DNA alterations in human cancer

    OpenAIRE

    Carter, Scott L.; Cibulskis, Kristian; Helman, Elena; McKenna, Aaron; Shen, Hui; Zack, Travis; Laird, Peter W.; Onofrio, Robert C.; Winckler, Wendy; Weir, Barbara A; Beroukhim, Rameen; Pellman, David; Levine, Douglas A.; Lander, Eric S.; Meyerson, Matthew

    2015-01-01

    We developed a computational method (ABSOLUTE) that infers tumor purity and malignant cell ploidy directly from analysis of somatic DNA alterations. ABSOLUTE can detect subclonal heterogeneity, somatic homozygosity, and calculate statistical sensitivity to detect specific aberrations. We used ABSOLUTE to analyze ovarian cancer data and identified pervasive subclonal somatic point mutations. In contrast, mutations occurring in key tumor suppressor genes, TP53 and NF1 were predominantly clonal ...

  2. High-precision Absolute Coordinate Measurement using Frequency Scanned Interferometry

    CERN Document Server

    Chen, Tianxiang; Riles, Keith; Li, Cheng

    2013-01-01

    In this paper, we report high-precision absolute position measurement performed with frequency scanned interferometry (FSI). We reported previously on measurement of absolute distance with FSI [1]. Absolute position is determined by several related absolute distances measured simultaneously. The achieved precision of 2-dimensional measurements is better than 1 micron, and in 3-dimensional measurements, the precision on X and Y is confirmed to be below 1 micron, while the confirmed precision on Z is about 2 microns, where the confirmation is limited by the lower precision of the moving stage in Z direction.

  3. The absolute disparity anomaly and the mechanism of relative disparities.

    Science.gov (United States)

    Chopin, Adrien; Levi, Dennis; Knill, David; Bavelier, Daphne

    2016-06-01

    There has been a long-standing debate about the mechanisms underlying the perception of stereoscopic depth and the computation of the relative disparities that it relies on. Relative disparities between visual objects could be computed in two ways: (a) using the difference in the object's absolute disparities (Hypothesis 1) or (b) using relative disparities based on the differences in the monocular separations between objects (Hypothesis 2). To differentiate between these hypotheses, we measured stereoscopic discrimination thresholds for lines with different absolute and relative disparities. Participants were asked to judge the depth of two lines presented at the same distance from the fixation plane (absolute disparity) or the depth between two lines presented at different distances (relative disparity). We used a single stimulus method involving a unique memory component for both conditions, and no extraneous references were available. We also measured vergence noise using Nonius lines. Stereo thresholds were substantially worse for absolute disparities than for relative disparities, and the difference could not be explained by vergence noise. We attribute this difference to an absence of conscious readout of absolute disparities, termed the absolute disparity anomaly. We further show that the pattern of correlations between vergence noise and absolute and relative disparity acuities can be explained jointly by the existence of the absolute disparity anomaly and by the assumption that relative disparity information is computed from absolute disparities (Hypothesis 1).

  4. Energy latency tradeoffs for medium access and sleep scheduling in wireless sensor networks

    Science.gov (United States)

    Gang, Lu

    Wireless sensor networks are expected to be used in a wide range of applications from environment monitoring to event detection. The key challenge is to provide energy efficient communication; however, latency remains an important concern for many applications that require fast response. The central thesis of this work is that energy efficient medium access and sleep scheduling mechanisms can be designed without necessarily sacrificing application-specific latency performance. We validate this thesis through results from four case studies that cover various aspects of medium access and sleep scheduling design in wireless sensor networks. Our first effort, DMAC, is to design an adaptive low latency and energy efficient MAC for data gathering to reduce the sleep latency. We propose staggered schedule, duty cycle adaptation, data prediction and the use of more-to-send packets to enable seamless packet forwarding under varying traffic load and channel contentions. Simulation and experimental results show significant energy savings and latency reduction while ensuring high data reliability. The second research effort, DESS, investigates the problem of designing sleep schedules in arbitrary network communication topologies to minimize the worst case end-to-end latency (referred to as delay diameter). We develop a novel graph-theoretical formulation, derive and analyze optimal solutions for the tree and ring topologies and heuristics for arbitrary topologies. The third study addresses the problem of minimum latency joint scheduling and routing (MLSR). By constructing a novel delay graph, the optimal joint scheduling and routing can be solved by M node-disjoint paths algorithm under multiple channel model. We further extended the algorithm to handle dynamic traffic changes and topology changes. A heuristic solution is proposed for MLSR under single channel interference. In the fourth study, EEJSPC, we first formulate a fundamental optimization problem that provides tunable

  5. Evaluation of the absolute regional temperature potential

    Directory of Open Access Journals (Sweden)

    D. T. Shindell

    2012-09-01

    Full Text Available The Absolute Regional Temperature Potential (ARTP is one of the few climate metrics that provides estimates of impacts at a sub-global scale. The ARTP presented here gives the time-dependent temperature response in four latitude bands (90–28° S, 28° S–28° N, 28–60° N and 60–90° N as a function of emissions based on the forcing in those bands caused by the emissions. It is based on a large set of simulations performed with a single atmosphere-ocean climate model to derive regional forcing/response relationships. Here I evaluate the robustness of those relationships using the forcing/response portion of the ARTP to estimate regional temperature responses to the historic aerosol forcing in three independent climate models. These ARTP results are in good accord with the actual responses in those models. Nearly all ARTP estimates fall within ±20% of the actual responses, though there are some exceptions for 90–28° S and the Arctic, and in the latter the ARTP may vary with forcing agent. However, for the tropics and the Northern Hemisphere mid-latitudes in particular, the ±20% range appears to be roughly consistent with the 95% confidence interval. Land areas within these two bands respond 39–45% and 9–39% more than the latitude band as a whole. The ARTP, presented here in a slightly revised form, thus appears to provide a relatively robust estimate for the responses of large-scale latitude bands and land areas within those bands to inhomogeneous radiative forcing and thus potentially to emissions as well. Hence this metric could allow rapid evaluation of the effects of emissions policies at a finer scale than global metrics without requiring use of a full climate model.

  6. Absolute parameters of young stars: QZ Carinae

    Science.gov (United States)

    Walker, W. S. G.; Blackford, M.; Butland, R.; Budding, E.

    2017-09-01

    New high-resolution spectroscopy and BVR photometry together with literature data on the complex massive quaternary star QZ Car are collected and analysed. Absolute parameters are found as follows. System A: M1 = 43 (±3), M2 = 19 (+3 -7), R1 = 28 (±2), R2 = 6 (±2), (⊙); T1 ∼ 28 000, T2 ∼ 33 000 K; System B: M1 = 30 (±3), M2 = 20 (±3), R1 = 10 (±0.5), R2 = 20 (±1), (⊙); T1 ∼ 36 000, T2 ∼ 30 000 K (model dependent temperatures). The wide system AB: Period = 49.5 (±1) yr, Epochs, conjunction = 1984.8 (±1), periastron = 2005.3 (±3) yr, mean separation = 65 (±3), (au); orbital inclination = 85 (+5 -15) deg, photometric distance ∼2700 (±300) pc, age = 4 (±1) Myr. Other new contributions concern: (a) analysis of the timing of minima differences (O - C)s for the eclipsing binary (System B); (b) the width of the eclipses, pointing to relatively large effects of radiation pressure; (c) inferences from the rotational widths of lines for both Systems A and B; and (d) implications for theoretical models of early-type stars. While feeling greater confidence on the quaternary's general parametrization, observational complications arising from strong wind interactions or other, unclear, causes still inhibit precision and call for continued multiwavelength observations. Our high-inclination value for the AB system helps to explain failures to resolve the wide binary in the previous years. The derived young age independently confirms membership of QZ Car to the open cluster Collinder 228.

  7. Absolute Radiometric Calibration of KOMPSAT-3A

    Science.gov (United States)

    Ahn, H. Y.; Shin, D. Y.; Kim, J. S.; Seo, D. C.; Choi, C. U.

    2016-06-01

    This paper presents a vicarious radiometric calibration of the Korea Multi-Purpose Satellite-3A (KOMPSAT-3A) performed by the Korea Aerospace Research Institute (KARI) and the Pukyong National University Remote Sensing Group (PKNU RSG) in 2015.The primary stages of this study are summarized as follows: (1) A field campaign to determine radiometric calibrated target fields was undertaken in Mongolia and South Korea. Surface reflectance data obtained in the campaign were input to a radiative transfer code that predicted at-sensor radiance. Through this process, equations and parameters were derived for the KOMPSAT-3A sensor to enable the conversion of calibrated DN to physical units, such as at-sensor radiance or TOA reflectance. (2) To validate the absolute calibration coefficients for the KOMPSAT-3A sensor, we performed a radiometric validation with a comparison of KOMPSAT-3A and Landsat-8 TOA reflectance using one of the six PICS (Libya 4). Correlations between top-of-atmosphere (TOA) radiances and the spectral band responses of the KOMPSAT-3A sensors at the Zuunmod, Mongolia and Goheung, South Korea sites were significant for multispectral bands. The average difference in TOA reflectance between KOMPSAT-3A and Landsat-8 image over the Libya 4, Libya site in the red-green-blue (RGB) region was under 3%, whereas in the NIR band, the TOA reflectance of KOMPSAT-3A was lower than the that of Landsat-8 due to the difference in the band passes of two sensors. The KOMPSAT-3Aensor includes a band pass near 940 nm that can be strongly absorbed by water vapor and therefore displayed low reflectance. Toovercome this, we need to undertake a detailed analysis using rescale methods, such as the spectral bandwidth adjustment factor.

  8. Supraspinal control of a short-latency cutaneous pathway to hindlimb motoneurons.

    Science.gov (United States)

    Fleshman, J W; Rudomin, P; Burke, R E

    1988-01-01

    The effects of two supraspinal systems on transmission through a short latency hindlimb cutaneous reflex pathway were studied in cats anesthetized with pentobarbital or alpha-chloralose. Fleshman et al. (1984) described a mixed excitatory-inhibitory input from low threshold superficial peroneal (SP) afferents to flexor digitorum longus (FDL) motoneurons with central latencies so short as to suggest a disynaptic component in the initial excitatory phase of the PSP. In the present study, conditioning stimulation of either the red nucleus (RN) or the pyramidal tract (PT) caused a marked decrease in latency and increase in amplitude of both the excitatory and inhibitory components of the SP PSP in FDL motoneurons and several other motoneuron species. The minimal central latencies of the conditioned initial excitatory phase of the PSPs were on the order of 1.5 ms, consistent with the possibility of a disynaptic linkage. The facilitatory effects of RN and PT conditioning were observed in both anesthetic conditions, although preparation-specific differences in latency were observed. Lesion experiments suggested that the interneurons involved in this pathway are located caudal to the L5 segment, most likely in segments L6 and L7.

  9. CD8α dendritic cells drive establishment of HSV-1 latency.

    Directory of Open Access Journals (Sweden)

    Kevin R Mott

    Full Text Available It is generally accepted that CD8 T cells play the key role to maintain HSV-1 latency in trigeminal ganglia of ocularly infected mice. Yet, comparably little is known about the role of innate immunity in establishment of viral latency. In the current study, we investigated whether CD8α DCs impact HSV-1 latency by examining latency in the trigeminal ganglia (TG of wild-type (WT C57BL/6 versus CD8α-/- (lack functional CD8 T cells and CD8α+ DCs, CD8β-/- (have functional CD8α+ T cells and CD8α+ DCs, and β2m-/- (lack functional CD8 T cells but have CD8α+ DCs mice as well as BXH2 (have functional CD8 T cells but lack CD8α+ DCs versus WT C3H (have functional CD8α T cells and CD8α+ DCs mice. We also determined whether the phenotype of CD8α-/- and BXH2 mice could be restored to that of WT mice by adoptive transfer of WT CD8+ T cells or bone marrow (BM derived CD8α+ DCs. Our results clearly demonstrate that CD8α DCs, rather than CD8 T cells, are responsible for enhanced viral latency and recurrences.

  10. The effect of water immersion on short-latency somatosensory evoked potentials in human

    Directory of Open Access Journals (Sweden)

    Sato Daisuke

    2012-01-01

    Full Text Available Abstract Background Water immersion therapy is used to treat a variety of cardiovascular, respiratory, and orthopedic conditions. It can also benefit some neurological patients, although little is known about the effects of water immersion on neural activity, including somatosensory processing. To this end, we examined the effect of water immersion on short-latency somatosensory evoked potentials (SEPs elicited by median nerve stimuli. Short-latency SEP recordings were obtained for ten healthy male volunteers at rest in or out of water at 30°C. Recordings were obtained from nine scalp electrodes according to the 10-20 system. The right median nerve at the wrist was electrically stimulated with the stimulus duration of 0.2 ms at 3 Hz. The intensity of the stimulus was fixed at approximately three times the sensory threshold. Results Water immersion significantly reduced the amplitudes of the short-latency SEP components P25 and P45 measured from electrodes over the parietal region and the P45 measured by central region. Conclusions Water immersion reduced short-latency SEP components known to originate in several cortical areas. Attenuation of short-latency SEPs suggests that water immersion influences the cortical processing of somatosensory inputs. Modulation of cortical processing may contribute to the beneficial effects of aquatic therapy. Trial Registration UMIN-CTR (UMIN000006492

  11. HIV-1 Tat and Viral Latency: What We Can Learn from Naturally Occurring Sequence Variations

    Science.gov (United States)

    Kamori, Doreen; Ueno, Takamasa

    2017-01-01

    Despite the effective use of antiretroviral therapy, the remainder of a latently HIV-1-infected reservoir mainly in the resting memory CD4+ T lymphocyte subset has provided a great setback toward viral eradication. While host transcriptional silencing machinery is thought to play a dominant role in HIV-1 latency, HIV-1 protein such as Tat, may affect both the establishment and the reversal of latency. Indeed, mutational studies have demonstrated that insufficient Tat transactivation activity can result in impaired transcription of viral genes and the establishment of latency in cell culture experiments. Because Tat protein is one of highly variable proteins within HIV-1 proteome, it is conceivable that naturally occurring Tat mutations may differentially modulate Tat functions, thereby influencing the establishment and/or the reversal of viral latency in vivo. In this mini review, we summarize the recent findings of Tat naturally occurring polymorphisms associating with host immune responses and we highlight the implication of Tat sequence variations in relation to HIV latency.

  12. Middle latency auditory evoked responses in normal term infants: a longitudinal study.

    Science.gov (United States)

    Rogers, S H; Edwards, D A; Henderson-Smart, D J; Pettigrew, A G

    1989-05-01

    Middle latency auditory evoked responses (MLAERs) were measured in 21 normal term infants, three to five days after birth and then at 6 weeks, 7 months and 1 year of age. A polyphasic waveform was elicited during natural sleep in all infants at each recording session by monaural click stimulation at a rate of 9 per second. A 70 dBHL stimulus was found to be optimal as the MLAER became less well defined when the stimulus intensity approached the threshold hearing level. The first 60 to 70 msec of the waveform was found to be most stable, with decreasing detectability of peaks at longer latencies. There was no change in wave latency or reproducibility of MLAERs recorded during different sleep states. Waves Po and Na showed a significant decrease in latency with increasing stimulus intensity at term and/or 6 weeks of age. This was not evident for the remainder of the waveform. Waves Po, Na, Pa, Nb, Pb and Nc exhibited significant decreases in latency with age, attaining values indistinguishable from adults by 7 months of age.

  13. Latency correction of event-related potentials between different experimental protocols

    Science.gov (United States)

    Iturrate, I.; Chavarriaga, R.; Montesano, L.; Minguez, J.; Millán, JdR

    2014-06-01

    Objective. A fundamental issue in EEG event-related potentials (ERPs) studies is the amount of data required to have an accurate ERP model. This also impacts the time required to train a classifier for a brain-computer interface (BCI). This issue is mainly due to the poor signal-to-noise ratio and the large fluctuations of the EEG caused by several sources of variability. One of these sources is directly related to the experimental protocol or application designed, and may affect the amplitude or latency of ERPs. This usually prevents BCI classifiers from generalizing among different experimental protocols. In this paper, we analyze the effect of the amplitude and the latency variations among different experimental protocols based on the same type of ERP. Approach. We present a method to analyze and compensate for the latency variations in BCI applications. The algorithm has been tested on two widely used ERPs (P300 and observation error potentials), in three experimental protocols in each case. We report the ERP analysis and single-trial classification. Main results. The results obtained show that the designed experimental protocols significantly affect the latency of the recorded potentials but not the amplitudes. Significance. These results show how the use of latency-corrected data can be used to generalize the BCIs, reducing the calibration time when facing a new experimental protocol.

  14. ScriptingRT: A Software Library for Collecting Response Latencies in Online Studies of Cognition.

    Directory of Open Access Journals (Sweden)

    Thomas W Schubert

    Full Text Available ScriptingRT is a new open source tool to collect response latencies in online studies of human cognition. ScriptingRT studies run as Flash applets in enabled browsers. ScriptingRT provides the building blocks of response latency studies, which are then combined with generic Apache Flex programming. Six studies evaluate the performance of ScriptingRT empirically. Studies 1-3 use specialized hardware to measure variance of response time measurement and stimulus presentation timing. Studies 4-6 implement a Stroop paradigm and run it both online and in the laboratory, comparing ScriptingRT to other response latency software. Altogether, the studies show that Flash programs developed in ScriptingRT show a small lag and an increased variance in response latencies. However, this did not significantly influence measured effects: The Stroop effect was reliably replicated in all studies, and the found effects did not depend on the software used. We conclude that ScriptingRT can be used to test response latency effects online.

  15. High-speed, fixed-latency serial links with Xilinx FPGAs

    Institute of Scientific and Technical Information of China (English)

    Xue LIU; Qing-xu DENG; Bo-ning HOU; Ze-ke WANG

    2014-01-01

    High-speed, fixed-latency serial links find application in distributed data acquisition and control systems, such as the timing trigger and control (TTC) system for high energy physics experiments. However, most high-speed serial transceivers do not keep the same chip latency after each power-up or reset, as there is no deterministic phase relationship between the transmitted and received clocks after each power-up. In this paper, we propose a fixed-latency serial link based on high-speed transceivers embedded in Xilinx field programmable gate arrays (FPGAs). First, we modify the configuration and clock distribution of the transceiver to eliminate the phase difference between the clock domains in the transmitter/receiver. Second, we use the internal alignment circuit of the transceiver and a digital clock manager (DCM)/phase-locked loop (PLL) based clock generator to eliminate the phase difference between the clock domains in the transmitter and receiver. The test results of the link latency are shown. Compared with existing solutions, our design not only implements fixed chip latency, but also reduces the average system lock time.

  16. Kinesiology taping does not change fibularis longus latency time and postural sway.

    Science.gov (United States)

    Correia, Christophe; Lopes, Susana; Gonçalves, Rafael; Torres, Rui; Pinho, Francisco; Gonçalves, Pedro; Rodrigues, Mário; Costa, Rui; Lopes, Mário; Ribeiro, Fernando

    2016-01-01

    Kinesiology tape seems to improve muscle force, although little is known regarding its effect on latency time and postural sway. To examine the effects of kinesiology taping on fibularis longus latency time and postural sway in healthy subjects. Thirty participants were equally randomized into three groups, two experimental groups receiving kinesiology tape (EG1, from origin to insertion; EG2, from insertion to origin) and a control group. Before and 20-min after the intervention, postural sway was assessed on a force platform and fibularis longus latency time was recorded with surface electromyography during a sudden inversion perturbation. At baseline, no differences were found between groups regarding age, anthropometrics variables, postural sway and fibularis longus latency time. In both experimental groups, the application of tape did not change postural sway and fibularis longus latency time (EG1: 93.7 ± 15.0 to 89.9 ± 15.6 ms; EG2, 81.24 ± 14.21 to 81.57 ± 16.64, p Kinesiology tape seems not to enhance fibularis longus reaction time and postural sway in young healthy subjects. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Classifier-based latency estimation: a novel way to estimate and predict BCI accuracy

    Science.gov (United States)

    Thompson, David E.; Warschausky, Seth; Huggins, Jane E.

    2013-02-01

    Objective. Brain-computer interfaces (BCIs) that detect event-related potentials (ERPs) rely on classification schemes that are vulnerable to latency jitter, a phenomenon known to occur with ERPs such as the P300 response. The objective of this work was to investigate the role that latency jitter plays in BCI classification. Approach. We developed a novel method, classifier-based latency estimation (CBLE), based on a generalization of Woody filtering. The technique works by presenting the time-shifted data to the classifier, and using the time shift that corresponds to the maximal classifier score. Main results. The variance of CBLE estimates correlates significantly (p < 10-42) with BCI accuracy in the Farwell-Donchin BCI paradigm. Additionally, CBLE predicts same-day accuracy, even from small datasets or datasets that have already been used for classifier training, better than the accuracy on the small dataset (p < 0.05). The technique should be relatively classifier-independent, and the results were confirmed on two linear classifiers. Significance. The results suggest that latency jitter may be an important cause of poor BCI performance, and methods that correct for latency jitter may improve that performance. CBLE can also be used to decrease the amount of data needed for accuracy estimation, allowing research on effects with shorter timescales.

  18. Repeater F waves: a comparison of sensitivity with sensory antidromic wrist-to-palm latency and distal motor latency in the diagnosis of carpal tunnel syndrome.

    Science.gov (United States)

    Macleod, W N

    1987-05-01

    Thirty-five thousand six hundred supramaximal shocks were applied to 209 healthy and 147 entrapped median nerves (carpal tunnel syndrome--CTS) to characterize the backfiring behavior of the alpha motor neuron pool of abductor pollicis brevis in health and the modifying effect of a compressive neuropathy. A contraction of the normal subpopulation of active F-wave generators was found in CTS, while active neurons backfired at higher than normal frequencies (p less than 0.001). These modifications in spinal behavior are reflected in the % Repeater F-wave value, whose sensitivity in the detection of CTS approaches that of sensory wrist-to-palm latency estimation. This technique offers an alternative to latency measurement in the diagnosis of CTS. An economical strategy for the electrodiagnosis of CTS is proposed.

  19. Plasma cell leukemia

    DEFF Research Database (Denmark)

    Fernández de Larrea, C; Kyle, R A; Durie, B G M

    2013-01-01

    Plasma cell leukemia (PCL) is a rare and aggressive variant of myeloma characterized by the presence of circulating plasma cells. It is classified as either primary PCL occurring at diagnosis or as secondary PCL in patients with relapsed/refractory myeloma. Primary PCL is a distinct clinic......-pathological entity with different cytogenetic and molecular findings. The clinical course is aggressive with short remissions and survival duration. The diagnosis is based upon the percentage (≥ 20%) and absolute number (≥ 2 × 10(9)/l) of plasma cells in the peripheral blood. It is proposed that the thresholds...... regimens and bortezomib-based regimens are recommended followed by high-dose therapy with autologous stem cell transplantation if feasible. Allogeneic transplantation can be considered in younger patients. Prospective multicenter studies are required to provide revised definitions and better understanding...

  20. Low latency on chip communication based on hybrid NOC Architecture using X-Y router

    Directory of Open Access Journals (Sweden)

    Tejas wini Deotare

    2014-05-01

    Full Text Available On-chip co mmunication has two different type of architecture which can be classified as Bus and mesh based Networks- on-Chip (No C. Each of them has diffe rent features and applications. In this paper, we construct the hybrid architecture with using bus and mesh NOC architecture. In the hybrid architecture, heavy communication affinity IPcores are placed in the same subsystem. and this large mesh No C get partitioned into several subsystems and one on one individual IPs, so that there is the reduction in the transmission latency of NoC.Efficient partition and mapping algorith m is proposed for reduction of the latency on the hybrid NOC arch itecture.It shows that an average latency improvement of 17.6% and more can be obtained when compared with the conventional mesh No C arch itecture.

  1. A new latency-reducing and energy-efficient protocol for the wireless sensor network

    Institute of Scientific and Technical Information of China (English)

    XIONG Junjie; QU Yugui; LIN Huahui; PAN Quanke; ZHAO Baohua

    2007-01-01

    This paper introduces a new protocol routing medium access control (RMAC) that integrates the routing and medium access control (MAC) layer protocol.They can both reduce latency and save energy in the wireless sensor network (WSN) while most others propose protocols that sacrifice latency for energy.To make RMAC fit WSN better,we designed an easy and efficient routing protocol base station flooding (BSF) and then integrated it with a MAC protocol timing out MAC (TMAC) [1],while traditionally BSF and TMAC work separately at two layers.We call this two-layer protocol (TLP).We theoretically proved the advantages of RMAC over TLP and evaluated RMAC over NS-2.The simulation results show that RMAC spends half the latency of TLP,as well as consumes less energy than TLE

  2. Managing Communication Latency-Hiding at Runtime for Parallel Programming Languages and Libraries

    CERN Document Server

    Kristensen, Mads Ruben Burgdorff

    2012-01-01

    This work introduces a runtime model for managing communication with support for latency-hiding. The model enables non-computer science researchers to exploit communication latency-hiding techniques seamlessly. For compiled languages, it is often possible to create efficient schedules for communication, but this is not the case for interpreted languages. By maintaining data dependencies between scheduled operations, it is possible to aggressively initiate communication and lazily evaluate tasks to allow maximal time for the communication to finish before entering a wait state. We implement a heuristic of this model in DistNumPy, an auto-parallelizing version of numerical Python that allows sequential NumPy programs to run on distributed memory architectures. Furthermore, we present performance comparisons for eight benchmarks with and without automatic latency-hiding. The results shows that our model reduces the time spent on waiting for communication as much as 27 times, from a maximum of 54% to only 2% of t...

  3. Fast response electromagnetic follow-ups from low latency GW triggers

    CERN Document Server

    Howell, E J; Rowlinson, A; Gao, H; Zhang, B; Tingay, S J; Boer, M; Wen, L

    2016-01-01

    We investigate joint low-latency gravitational wave (GW) detection and prompt electromagnetic (EM) follow-up observations of coalescing binary neutron stars (BNSs). Assuming that BNS mergers are associated with short duration gamma ray bursts (SGRBs), we evaluate if rapid EM follow-ups can capture the prompt emission, early engine activity or reveal any potential by-products such as magnetars or fast radio bursts. To examine the expected performance of extreme low-latency search pipelines, we simulate a population of coalescing BNSs and use these to estimate the detectability and localisation efficiency at different times before merger. Using observational SGRB flux data corrected to the range of the advanced GW interferometric detectors, we determine what EM observations could be achieved from low-frequency radio up to high energy $\\gamma$-ray. We show that while challenging, breakthrough multi-messenger science is possible through low latency pipelines.

  4. Anti-HIV-1 ADCC antibodies following latency reversal and treatment interruption

    DEFF Research Database (Denmark)

    Lee, Wen Shi; Kristensen, Anne B; Rasmussen, Thomas A

    2017-01-01

    There is growing interest in utilizing antibody-dependent cellular cytotoxicity (ADCC) to eliminate infected cells following reactivation from HIV-1 latency. A potential barrier is that HIV-1-specific ADCC antibodies decline in patients on long-term antiretroviral therapy (ART) and may...... not be sufficient to eliminate reactivated latently infected cells. It is not known whether reactivation from latency with latency-reversing agents (LRA) could provide sufficient antigenic stimulus to boost HIV-1-specific ADCC. We find that treatment with the LRA panobinostat or a short analytical treatment......) trial robustly boosted HIV-1 gp120-specific Fc receptor-binding antibodies and ADCC against HIV-1-infected cells in vitro These results show there is a lag between viral recrudescence and the boosting of ADCC antibodies, which has implications for strategies towards eliminating latently infected cells...

  5. Measurement and analysis of workload effects on fault latency in real-time systems

    Science.gov (United States)

    Woodbury, Michael H.; Shin, Kang G.

    1990-01-01

    The authors demonstrate the need to address fault latency in highly reliable real-time control computer systems. It is noted that the effectiveness of all known recovery mechanisms is greatly reduced in the presence of multiple latent faults. The presence of multiple latent faults increases the possibility of multiple errors, which could result in coverage failure. The authors present experimental evidence indicating that the duration of fault latency is dependent on workload. A synthetic workload generator is used to vary the workload, and a hardware fault injector is applied to inject transient faults of varying durations. This method makes it possible to derive the distribution of fault latency duration. Experimental results obtained from the fault-tolerant multiprocessor at the NASA Airlab are presented and discussed.

  6. Absolute chronology and stratigraphy of Lepenski Vir

    Directory of Open Access Journals (Sweden)

    Borić Dušan

    2007-01-01

    Full Text Available In the last decade, a number of specialist analyses were made on the material from old excavations of Mesolithic-Neolithic sites in the Danube Gorges. These new results altered significantly our understanding of the Lepenski Vir culture. The question of chronology of this regional phenomenon has been acute since the discovery of Lepenski Vir in the 1960s, and it remains of key importance for understanding the character of Mesolithic-Neolithic transformations in this and the neighbouring regions. The most heated debate was fuelled by the initial stratigraphic and chronological attribution of the type-site itself. There remained the question about the adequate dating of the most prominent phase at this site characterized by buildings with trapezoidal bases covered with limestone floors and with rectangular stone-lined hearths placed in the centre of these features. There have been suggestions that these features also contain Early Neolithic Starčevo type pottery and other similar items of material culture and should thus be dated to the Early Neolithic historical context. Moreover, the first series of conventional radiocarbon determinations (21 dates also suggested that the absolute chronology of these features should be confined to the period from around 6400-5500 cal BC (Fig. 1. Due to the importance of defining more precisely the chronology for the start of construction of these particular features at Lepenski Vir and for establishing the life-span of these buildings and their associated material culture, we have AMS (Accelerator Mass Spectrometry dated a number of contexts from this site. The results are presented in this paper. The project was made possible through the Oxford Radiocarbon Accelerate Dating Service (ORADS programme funded by the Arts and Humanities Research Council (AHRC and the Natural Environment Research Council (NERC of the Great Britain. Apart from those dates presented in this paper, there are 29 previously published

  7. Absolute instability in viscoelastic mixing layers

    Science.gov (United States)

    Ray, Prasun K.; Zaki, Tamer A.

    2014-01-01

    The spatiotemporal linear stability of viscoelastic planar mixing layers is investigated. A one-parameter family of velocity profiles is used as the base state with the parameter, S, controlling the amount of shear and backflow. The influence of viscoelasticity in dilute polymer solutions is modeled with the Oldroyd-B and FENE-P constitutive equations. Both models require the specification of the ratio of the polymer-relaxation and convective time scales (the Weissenberg number, We) and the ratio of solvent and solution viscosities (β). The maximum polymer extensibility, L, must also be specified for the FENE-P model. We examine how the variation of these parameters along with the Reynolds number, Re, affects the minimum value of S at which the flow becomes locally absolutely unstable. With the Oldroyd-B model, the influence of viscoelasticity is shown to be almost fully captured by the elasticity, E^* equiv (1-β ) We/Re, and Scrit decreases as elasticity is increased, i.e., elasticity is destabilizing. A simple approximate dispersion relation obtained via long-wave asymptotic analysis is shown to accurately capture this destabilizing influence. Results obtained with the FENE-P model exhibit a rich variety of behavior. At large values of the extensibility, L, results are similar to those for the Oldroyd-B fluid as expected. However, when the extensibility is reduced to more realistic values (L ≈ 100), one must consider the scaled shear rate, η _c equiv We S/2L, in addition to the elasticity. When ηc is large, the base-state polymer stress obtained by the FENE-P model is reduced, and there is a corresponding reduction in the overall influence of viscoelasticity on stability. Additionally, elasticity exhibits a stabilizing effect which is driven by the streamwise-normal perturbation polymer stress. As ηc is reduced, the base-state and perturbation normal polymer stresses predicted by the FENE-P model move towards the Oldroyd-B values, and the destabilizing

  8. Ablation of STAT3 in the B Cell Compartment Restricts Gammaherpesvirus Latency In Vivo

    Science.gov (United States)

    Reddy, Sandeep Steven; Foreman, Hui-Chen Chang; Sioux, Thubten Ozula; Park, Gee Ho; Poli, Valeria; Reich, Nancy C.

    2016-01-01

    ABSTRACT A challenging property of gammaherpesviruses is their ability to establish lifelong persistence. The establishment of latency in B cells is thought to involve active virus engagement of host signaling pathways. Pathogenic effects of these viruses during latency or following reactivation can be devastating to the host. Many cancers, including those associated with members of the gammaherpesvirus family, Kaposi’s sarcoma-associated herpesvirus and Epstein-Barr virus, express elevated levels of active host signal transducer and activator of transcription-3 (STAT3). STAT3 is activated by tyrosine phosphorylation in response to many cytokines and can orchestrate effector responses that include proliferation, inflammation, metastasis, and developmental programming. However, the contribution of STAT3 to gammaherpesvirus pathogenesis remains to be completely understood. This is the first study to have identified STAT3 as a critical host determinant of the ability of gammaherpesvirus to establish long-term latency in an animal model of disease. Following an acute infection, murine gammaherpesvirus 68 (MHV68) established latency in resident B cells, but establishment of latency was dramatically reduced in animals with a B cell-specific STAT3 deletion. The lack of STAT3 in B cells did not impair germinal center responses for immunoglobulin (Ig) class switching in the spleen and did not reduce either total or virus-specific IgG titers. Although ablation of STAT3 in B cells did not have a global effect on these assays of B cell function, it had long-term consequences for the viral load of the host, since virus latency was reduced at 6 to 8 weeks postinfection. Our findings establish host STAT3 as a mediator of gammaherpesvirus persistence. PMID:27486189

  9. Role of latency jittering correction in motion-onset VEP amplitude decay during prolonged visual stimulation.

    Science.gov (United States)

    Kremláček, J; Hulan, M; Kuba, M; Kubová, Z; Langrová, J; Vít, F; Szanyi, J

    2012-06-01

    Visual evoked potentials to motion-onset stimulation (M-VEPs) gradually attenuate in amplitude during examination. The observed decline in averaged responses can be caused by decreases in single response magnitudes and/or increased variability in a response delays, that is, latency jittering. To illuminate the origins of the suppression of M-VEPs during stimuli repetition, we used correlation technique to estimate an upper bound of possible latency jittering of single sweeps and we evaluated the effect of its correction on the amplitudes of three M-VEP dominant peaks P1, N2 and P3. During prolonged visual motion stimulation, the variability of corrective latency shifts in the occipital region increased (r = 0.35: 0.44) and the number of single responses corresponding to the average curve declined in occipital and parietal derivations (r = -0.48: -0.62). While the P1 peak amplitude did not exhibit any time-specific behaviour, the N2 amplitude exhibited a significant decay of 29.4% that was partially reduced to 16.6% in the central occipital derivation by the latency jitter and non-correspondence corrections. The strongest attenuation (32.7%) was observed in the P3 amplitude and was less sensitive to the corrections, dropping only to 27.9%. The main part of the response suppression to repeated motion stimulation was caused by amplitude drop and represents non-stationary process that likely correspond to a fatigue model. The rise of variability in latency jitter correction and the reduction in single responses correlated with the M-VEP were significant factors associated with prolonged motion stimulation. The relation of these parameters to a hypothetical veridical response is ambiguous and can be caused by a time shift of the response or by a change of signal-to-noise ratio. Using selective averaging and latency jitter correction, the effect of response suppression was partially removed.

  10. The influence of aging on interaural asymmetries in middle latency response amplitude.

    Science.gov (United States)

    Weihing, Jeffrey; Musiek, Frank

    2014-04-01

    Auditory-evoked potentials (EPs) provide a more objective assessment of central auditory nervous system (CANS) dysfunction when compared to behavioral measures because they do not require a behavioral response (Anderson and Kraus, 2010). In this regard, the middle latency response (MLR) has been considered an important component of CANS assessment (Jerger et al, 1988); however, its large within-group variability limits its usefulness (Musiek et al, 1999). It has been argued that performing intratest calculations on the MLR (e.g., difference in EP amplitude when stimulating the left ear versus the right ear) can reduce the within-group variability of the MLR and enhance its clinical usefulness (Musiek et al, 1999; Weihing et al, 2012). To date, it has not been investigated how well these MLR intratest measures reduce within-group variability in adults of various ages, nor has it been shown that these intratest measures are sensitive to aging-related changes in the CANS. The two primary goals of the present study were (1) to determine if calculating an intratest MLR measure, the difference in MLR Na-Pa peak-to-peak amplitude on left versus right ear stimulation (i.e., "ear effects"), will reduce within-group variability in adults of various ages; and (2) to determine if ear effect magnitude will change as a function of aging. Ear effects were measured in both quiet and in noise to determine if the addition of noise enhanced any age-related-effects. A cross-sectional study was conducted. The researchers studied 30 adults ranging in age from 20-80 yr with hearing sensitivity of 25 dB HL or better at the octave frequencies from 500-2000 Hz, and no history of neurologic issues. Adults were assigned to one of three age groups based on their chronological age, which were young adults, middle-aged adults, and older adults. MLRs were acquired using a Nicolet Spirit 2000 during a single laboratory visit. To determine if within-group variability decreased significantly with

  11. Absolute Humidity and the Seasonality of Influenza (Invited)

    Science.gov (United States)

    Shaman, J. L.; Pitzer, V.; Viboud, C.; Grenfell, B.; Goldstein, E.; Lipsitch, M.

    2010-12-01

    Much of the observed wintertime increase of mortality in temperate regions is attributed to seasonal influenza. A recent re-analysis of laboratory experiments indicates that absolute humidity strongly modulates the airborne survival and transmission of the influenza virus. Here we show that the onset of increased wintertime influenza-related mortality in the United States is associated with anomalously low absolute humidity levels during the prior weeks. We then use an epidemiological model, in which observed absolute humidity conditions temper influenza transmission rates, to successfully simulate the seasonal cycle of observed influenza-related mortality. The model results indicate that direct modulation of influenza transmissibility by absolute humidity alone is sufficient to produce this observed seasonality. These findings provide epidemiological support for the hypothesis that absolute humidity drives seasonal variations of influenza transmission in temperate regions. In addition, we show that variations of the basic and effective reproductive numbers for influenza, caused by seasonal changes in absolute humidity, are consistent with the general timing of pandemic influenza outbreaks observed for 2009 A/H1N1 in temperate regions. Indeed, absolute humidity conditions correctly identify the region of the United States vulnerable to a third, wintertime wave of pandemic influenza. These findings suggest that the timing of pandemic influenza outbreaks is controlled by a combination of absolute humidity conditions, levels of susceptibility and changes in population mixing and contact rates.

  12. Novalis' Poetic Uncertainty: A "Bildung" with the Absolute

    Science.gov (United States)

    Mika, Carl

    2016-01-01

    Novalis, the Early German Romantic poet and philosopher, had at the core of his work a mysterious depiction of the "absolute." The absolute is Novalis' name for a substance that defies precise knowledge yet calls for a tentative and sensitive speculation. How one asserts a truth, represents an object, and sets about encountering things…

  13. A Global Forecast of Absolute Poverty and Employment.

    Science.gov (United States)

    Hopkins, M. J. D.

    1980-01-01

    Estimates are made of absolute poverty and employment under the hypothesis that existing trends continue. Concludes that while the number of people in absolute poverty is not likely to decline by 2000, the proportion will fall. Jobs will have to grow 3.9% per year in developing countries to achieve full employment. (JOW)

  14. Determination of Absolute Zero Using a Computer-Based Laboratory

    Science.gov (United States)

    Amrani, D.

    2007-01-01

    We present a simple computer-based laboratory experiment for evaluating absolute zero in degrees Celsius, which can be performed in college and undergraduate physical sciences laboratory courses. With a computer, absolute zero apparatus can help demonstrators or students to observe the relationship between temperature and pressure and use…

  15. Absolute instruments and perfect imaging in geometrical optics

    CERN Document Server

    Tyc, Tomas; Sarbort, Martin; Bering, Klaus

    2011-01-01

    We investigate imaging by spherically symmetric absolute instruments that provide perfect imaging in the sense of geometrical optics. We derive a number of properties of such devices, present a general method for designing them and use this method to propose several new absolute instruments, in particular a lens providing a stigmatic image of an optically homogeneous region and having a moderate refractive index range.

  16. ABSOLUTE STABILITY OF GENERAL LURIE DISCRETE NONLINEAR CONTROL SYSTEMS

    Institute of Scientific and Technical Information of China (English)

    GAN Zuoxin; HAN Jingqing; ZHAO Suxia; WU Yongxian

    2002-01-01

    In the present paper, the absolute stability of general Lurie discrete nonlinear control systems has been discussed by Lyapunov function approach. A sufficient condition of absolute stability for the general Lurie discrete nonlinear control systems is derived, and some necessary and sufficient conditions are obtained in special cases. Meanwhile, we give a simple example to illustrate the effectiveness of the results.

  17. On the Mean Absolute Error in Inverse Binomial Sampling

    OpenAIRE

    Mendo, Luis

    2009-01-01

    A closed-form expression and an upper bound are obtained for the mean absolute error of the unbiased estimator of a probability in inverse binomial sampling. The results given permit the estimation of an arbitrary probability with a prescribed level of the normalized mean absolute error.

  18. Advanced techniques for the analysis of crisis stability, deterrence, and latency

    Energy Technology Data Exchange (ETDEWEB)

    Canavan, G.H.

    1998-12-31

    This is the final report of a one-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). The principal results of studies on crisis stability, deterrence, and latency are presented in their order of development. They capture the main features of stability analysis; relate first strike, crisis, and arms control stability as seen from US and Russian perspective; and address whether different metrics, uncertain damage preferences, or the deployment of defenses can be destabilizing. The report explores differences between unilateral and proportional force reductions in the region of deep reductions where concern shifts from stability to latency.

  19. Parametric inference of neuronal response latency in presence of a background signal

    DEFF Research Database (Denmark)

    Tamborrino, Massimiliano; Ditlevsen, Susanne; Lansky, Petr

    2013-01-01

    Neurons are commonly characterized by spontaneous generation of action potentials (spikes), which appear without any apparent or controlled stimulation. When a stimulus is applied, the spontaneous firing may prevail and hamper identification of the effect of the stimulus. Therefore, for any...... will persist even when sample size is increasing. The first question is: what is the response latency to the stimulus? Answering this question becomes even more difficult if the latency is of a complex nature, for example composed of a physically implied deterministic part and a stochastic part. This scenario...

  20. Model emulates human smooth pursuit system producing zero-latency target tracking.

    Science.gov (United States)

    Bahill, A T; McDonald, J D

    1983-01-01

    Humans can overcome the 150 ms time delay of the smooth pursuit eye movement system and track smoothly moving visual targets with zero-latency. Our target-selective adaptive control model can also overcome an inherent time delay and produce zero-latency tracking. No other model or man-made system can do this. Our model is physically realizable and physiologically realistic. The technique used in our model should be useful for analyzing other time-delay systems, such as man-machine systems and robots.

  1. Regulation of latency to lytic life cycle:multiple tricks by KSHV RTA

    Institute of Scientific and Technical Information of China (English)

    Jiemin Wong

    2010-01-01

    @@ Higher Education Press and Springer-Verlag Berlin Heidelberg 2010The herpesviruses are large enveloped DNA viruses that infect a wide spectrum hosts including human being. A key characteristic of all herpesviruses is their ability to establish life-time latency within the infected host and to periodically reactivate and enter the iytic replication to produce infectious virus progeny. During latency the 120-300 kb double-stranded DNA genomes of these viruses are maintained as multiple copies of circular episomes within the nuclei of the host cells. Lytic replication is marked by an increase in viral gene expression and the production of infectious virus progeny.

  2. VARICELLA ZOSTER VIRUS-ITS PATHOGENESIS, LATENCY & CELL-MEDIATED IMMUNITY

    Directory of Open Access Journals (Sweden)

    Anis Ahmed

    2013-07-01

    Full Text Available Varicella zoster virus causes primary infection as chickenpox, at which time latencyis established in the neurons of the dorsal root ganglia or ganglia of the cranial nerves.Reactivation produces herpes zoster infection (HZI, commonly called shingles. Anunderstanding of the mechanisms of latency is crucial in developing effective therapies forVZV infections of the nervous system. This article describes the pathogenesis of VZVwhich includes immune response to the virus, immune evasion by the virus, mechanism ofits latency and cell-mediated immunity.

  3. Influence of network latency in a remote control system using haptic media

    Science.gov (United States)

    Asano, Toshio; Ishibashi, Yutaka; Kurokawa, Youichi

    2006-10-01

    This paper deals with a remote control system which controls a haptic interface device with another remote haptic interface device. Applications of the system include a remote drawing instruction system, a remote calligraphy system and a remote medical operation system. This paper examines the influence of network latency on the output quality of haptic media by subjective assessment in the remote drawing instruction system. As a result, we show that the instructor has smaller Mean Opinion Score (MOS) values than the learner, and the MOS value can be estimated with high accuracy from the summation of the network latency from an instructor's terminal to a learner's terminal and that in the opposite direction.

  4. An Ultra-Low-Latency Geo-Routing Scheme for Team-Based Unmanned Vehicular Applications

    KAUST Repository

    Bader, Ahmed

    2016-02-26

    Results and lessons learned from the implementation of a novel ultra low-latency geo-routing scheme are presented in this paper. The geo-routing scheme is intended for team-based mobile systems whereby a cluster of unmanned autonomous vehicles are deployed to accomplish a critical mission under human supervision. The contention-free nature of the developed scheme lends itself to jointly achieve lower latency and higher throughput. Implementation challenges are presented and corresponding resolutions are discussed herewith. © 2015 IEEE.

  5. Optimized Interface Diversity for Ultra-Reliable Low Latency Communication (URLLC)

    DEFF Research Database (Denmark)

    Nielsen, Jimmy Jessen; Liu, Rongkuan; Popovski, Petar

    2017-01-01

    technology. Our approach is to use rateless codes to seamlessly distribute coded payload and redundancy data across multiple available communication interfaces. We formulate an optimization problem to find the payload allocation weights that maximize the reliability at specific target latency values......An important ingredient of the future 5G systems will be Ultra-Reliable Low-Latency Communication (URLLC). A way to offer URLLC without intervention in the baseband/PHY layer design is to use interface diversity and integrate multiple communication interfaces, each interface based on a different...

  6. A developmental study of latent absolute pitch memory.

    Science.gov (United States)

    Jakubowski, Kelly; Müllensiefen, Daniel; Stewart, Lauren

    2017-03-01

    The ability to recall the absolute pitch level of familiar music (latent absolute pitch memory) is widespread in adults, in contrast to the rare ability to label single pitches without a reference tone (overt absolute pitch memory). The present research investigated the developmental profile of latent absolute pitch (AP) memory and explored individual differences related to this ability. In two experiments, 288 children from 4 to12 years of age performed significantly above chance at recognizing the absolute pitch level of familiar melodies. No age-related improvement or decline, nor effects of musical training, gender, or familiarity with the stimuli were found in regard to latent AP task performance. These findings suggest that latent AP memory is a stable ability that is developed from as early as age 4 and persists into adulthood.

  7. The determination of the link with the smallest end-to-end network latency in ethernet architecture

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Ethernet fundamental and its data transmission model are introduced in brief and end-to-end network latency was analyzed in this paper. On the premise of not considering transmission quality and transmission cost, latency was the function of the rest of network resource parameter (NRP). The relation between the number of nodes and that of end-to-end links was presented. In ethernet architecture, the algorithm to determine the link with the smallest latency is a polynomial issue when the number of network nodes is limited, so it can be solved by way of polynomial equations. Latency measuring is the key issue to determine the link with the smallest network latency. 3-node brigade (regiment) level network centric warfare (NCW) demonstration platform was studied and the latency between the detectors and weapon control stations was taken as an example. The algorithm of end-to-end network latency and link information in NCW was presented. The algorithm program based on Server/Client architecture was developed. The data transmission optimal link is one whose end-to-end latency is the smallest. This paper solves the key issue to determine the link whose end-to-end latency is the smallest in ethernet architecture. The study can be widely applied to determine the optimal link which is in the complex network environment of multiple service provision points.

  8. Simulation Based Studies of Low Latency Teleoperations for NASA Exploration Missions

    Science.gov (United States)

    Gernhardt, Michael L.; Crues, Edwin Z.; Bielski, Paul; Dexter, Dan; Litaker, Harry L.; Chappell, Steven P.; Beaton, Kara H.; Bekdash, Omar S.

    2017-01-01

    Human exploration of Mars will involve both crewed and robotic systems. Many mission concepts involve the deployment and assembly of mission support assets prior to crew arrival on the surface. Some of these deployment and assembly activities will be performed autonomously while others will be performed using teleoperations. However, significant communications latencies between the Earth and Mars make teleoperations challenging. Alternatively, low latency teleoperations are possible from locations in Mars orbit like Mars' moons Phobos and Deimos. To explore these latency opportunities, NASA is conducting a series of studies to investigate the effects of latency on telerobotic deployment and assembly activities. These studies are being conducted in laboratory environments at NASA's Johnson Space Center (JSC), the Human Exploration Research Analog (HERA) at JSC and the NASA Extreme Environment Mission Operations (NEEMO) underwater habitat off the coast of Florida. The studies involve two human-in-the-loop interactive simulations developed by the NASA Exploration Systems Simulations (NExSyS) team at JSC. The first simulation investigates manipulation related activities while the second simulation investigates mobility related activities. The first simulation provides a simple real-time operator interface with displays and controls for a simulated 6 degree of freedom end effector. The initial version of the simulation uses a simple control mode to decouple the robotic kinematic constraints and a communications delay to model latency effects. This provides the basis for early testing with more detailed manipulation simulations planned for the future. Subjects are tested using five operating latencies that represent teleoperation conditions from local surface operations to orbital operations at Phobos, Deimos and ultimately high Martian orbit. Subject performance is measured and correlated with three distance-to-target zones of interest. Each zone represents a target

  9. CMOS MEMS capacitive absolute pressure sensor

    Science.gov (United States)

    Narducci, M.; Yu-Chia, L.; Fang, W.; Tsai, J.

    2013-05-01

    This paper presents the design, fabrication and characterization of a capacitive pressure sensor using a commercial 0.18 µm CMOS (complementary metal-oxide-semiconductor) process and postprocess. The pressure sensor is capacitive and the structure is formed by an Al top electrode enclosed in a suspended SiO2 membrane, which acts as a movable electrode against a bottom or stationary Al electrode fixed on the SiO2 substrate. Both the movable and fixed electrodes form a variable parallel plate capacitor, whose capacitance varies with the applied pressure on the surface. In order to release the membranes the CMOS layers need to be applied postprocess and this mainly consists of four steps: (1) deposition and patterning of PECVD (plasma-enhanced chemical vapor deposition) oxide to protect CMOS pads and to open the pressure sensor top surface, (2) etching of the sacrificial layer to release the suspended membrane, (3) deposition of PECVD oxide to seal the etching holes and creating vacuum inside the gap, and finally (4) etching of the passivation oxide to open the pads and allow electrical connections. This sensor design and fabrication is suitable to obey the design rules of a CMOS foundry and since it only uses low-temperature processes, it allows monolithic integration with other types of CMOS compatible sensors and IC (integrated circuit) interface on a single chip. Experimental results showed that the pressure sensor has a highly linear sensitivity of 0.14 fF kPa-1 in the pressure range of 0-300 kPa.

  10. On Novel Mechanism of a Pump Electromagnetic Wave Absolute Two-Plasmon Parametric Decay Instability Excitation in Tokamak ECRH Experiments

    CERN Document Server

    Gusakov, E Z

    2016-01-01

    Novel mechanism leading to excitation of absolute two plasmon parametric decay instability (TPDI) of a pump extraordinary (X) wave is discussed. It is shown that the upper hybrid (UH) plasmon can be 3D trapped in the presence of both a nonmonotonous density profile and a finite-size pump beam in a plane perpendicular to the plasma inhomogeneity direction. This leads to excitation of the absolute TPDI of the pump X wave, which manifests itself in temporal exponential growth of the trapped daughter UH wave amplitude and is perhaps the most dangerous instability for mm-waves, widely utilized nowadays in tokamak and stellarators for local plasma heating and current drive and being considered for application in ITER.

  11. HDAC inhibition induces HIV-1 protein and enables immune-based clearance following latency reversal

    DEFF Research Database (Denmark)

    Wu, Guoxin; Swanson, Michael; Talla, Aarthi

    2017-01-01

    Promising therapeutic approaches for eradicating HIV include transcriptional activation of provirus from latently infected cells using latency-reversing agents (LRAs) and immune-mediated clearance to purge reservoirs. Accurate detection of cells capable of producing viral antigens and virions, an...

  12. Histone modifications induced by MDV infection at early cytolytic and latency phases

    Science.gov (United States)

    Background: Marek’s disease (MD) is a highly contagious, lymphomatous disease of chickens induced by a herpesvirus, Marek’s disease virus (MDV) that is the cause of major annual losses to the poultry industry. MD pathogenesis involves multiple stages including an early cytolytic phase and latency, a...

  13. Evaluation of DECT for low latency real-time industrial control networks

    NARCIS (Netherlands)

    Das, Kallol; Havinga, Paul J.M.

    2013-01-01

    Wireless sensor networks (WSNs) have revolutionized the industrial networks by enabling wireless sensing and control to the machine parts where wiring is impossible. However, new challenges in terms of communication reliability and latency, appear with the advances in the industrial wireless control

  14. Low Latency Network-on-Chip Router Microarchitecture Using Request Masking Technique

    Directory of Open Access Journals (Sweden)

    Alireza Monemi

    2015-01-01

    Full Text Available Network-on-Chip (NoC is fast emerging as an on-chip communication alternative for many-core System-on-Chips (SoCs. However, designing a high performance low latency NoC with low area overhead has remained a challenge. In this paper, we present a two-clock-cycle latency NoC microarchitecture. An efficient request masking technique is proposed to combine virtual channel (VC allocation with switch allocation nonspeculatively. Our proposed NoC architecture is optimized in terms of area overhead, operating frequency, and quality-of-service (QoS. We evaluate our NoC against CONNECT, an open source low latency NoC design targeted for field-programmable gate array (FPGA. The experimental results on several FPGA devices show that our NoC router outperforms CONNECT with 50% reduction of logic cells (LCs utilization, while it works with 100% and 35%~20% higher operating frequency compared to the one- and two-clock-cycle latency CONNECT NoC routers, respectively. Moreover, the proposed NoC router achieves 2.3 times better performance compared to CONNECT.

  15. Urethral sensory threshold and urethro-anal reflex latency in continent women.

    Science.gov (United States)

    Cavalcanti, Geraldo de Aguiar; Bruschini, Homero; Manzano, Gilberto M; Giuliano, Lydia P; Nóbrega, João Antônio M; Srougi, Miguel

    2007-01-01

    The sensory evaluation of the lower urinary tract is summarized in the bladder proprioceptive sensitivity during cystometry. Experimental studies suggest that abnormalities of the urethral innervation and micturition reflex can be related to the presence of continence disturbances. This study aimed to measure the urethral sensory threshold and the urethro-anal reflex latency in healthy volunteers, establishing reading criteria, comparing the results and technique used with the literature and verifying the effect of physiological factors. Thirty healthy female volunteers were studied. They had an absence of genital or urinary complaints and had undergone no previous pelvic or vaginal procedures. The measurement of the urethral sensory threshold and urethro-anal reflex latency were performed as described. The determination of the urethral sensory threshold and urethro-anal reflex latency were obtained in 96.6% of the volunteers. The electrophysiological parameters did not correlate with age, parity or number of vaginal deliveries. There was a positive association of the urethral sensory threshold with height. Technical aspects were considered and compared with those in the literature as well as the advantages and limitations of the method. The measurement of the urethral sensory threshold and urethro-anal reflex latency presented consistent recordings. The urethral sensory threshold should be analyzed carefully in individuals with height above the population average. Subsequent observations are necessary to clarify their function in patients with continence disturbances and to measure the urethral function, but these values can be used as normal parameters for comparison.

  16. Working Memory Updating Latency Reflects the Cost of Switching between Maintenance and Updating Modes of Operation

    Science.gov (United States)

    Kessler, Yoav; Oberauer, Klaus

    2014-01-01

    Updating and maintenance of information are 2 conflicting demands on working memory (WM). We examined the time required to update WM (updating latency) as a function of the sequence of updated and not-updated items within a list. Participants held a list of items in WM and updated a variable subset of them in each trial. Four experiments that vary…

  17. Flash Memory Reliability: Read, Program, and Erase Latency Versus Endurance Cycling

    Science.gov (United States)

    Heidecker, Jason

    2010-01-01

    This report documents the efforts and results of the fiscal year (FY) 2010 NASA Electronic Parts and Packaging Program (NEPP) task for nonvolatile memory (NVM) reliability. This year's focus was to measure latency (read, program, and erase) of NAND Flash memories and determine how these parameters drift with erase/program/read endurance cycling.

  18. Fuzzy Logic based Handoff Latency Reduction Mechanism in Layer 2 of Heterogeneous Mobile IPv6 Networks

    Science.gov (United States)

    Anwar, Farhat; Masud, Mosharrof H.; Latif, Suhaimi A.

    2013-12-01

    Mobile IPv6 (MIPv6) is one of the pioneer standards that support mobility in IPv6 environment. It has been designed to support different types of technologies for providing seamless communications in next generation network. However, MIPv6 and subsequent standards have some limitations due to its handoff latency. In this paper, a fuzzy logic based mechanism is proposed to reduce the handoff latency of MIPv6 for Layer 2 (L2) by scanning the Access Points (APs) while the Mobile Node (MN) is moving among different APs. Handoff latency occurs when the MN switches from one AP to another in L2. Heterogeneous network is considered in this research in order to reduce the delays in L2. Received Signal Strength Indicator (RSSI) and velocity of the MN are considered as the input of fuzzy logic technique. This technique helps the MN to measure optimum signal quality from APs for the speedy mobile node based on fuzzy logic input rules and makes a list of interfaces. A suitable interface from the list of available interfaces can be selected like WiFi, WiMAX or GSM. Simulation results show 55% handoff latency reduction and 50% packet loss improvement in L2 compared to standard to MIPv6.

  19. Measuring the Latency of an Augmented Reality System for Robot-Assisted Minimally Invasive Surgery

    DEFF Research Database (Denmark)

    Jørgensen, Martin Kibsgaard; Kraus, Martin

    2017-01-01

    visual communication in training for robot-assisted minimally invasive surgery with da Vinci surgical systems. To make sure that our augmented reality system provides the best possible user experience, we investigated the video latency of the da Vinci surgical system and how the components of our system...

  20. Nucleophosmin phosphorylation by v-cyclin-CDK6 controls KSHV latency.

    Directory of Open Access Journals (Sweden)

    Grzegorz Sarek

    2010-03-01

    Full Text Available Nucleophosmin (NPM is a multifunctional nuclear phosphoprotein and a histone chaperone implicated in chromatin organization and transcription control. Oncogenic Kaposi's sarcoma herpesvirus (KSHV is the etiological agent of Kaposi's sarcoma, primary effusion lymphoma (PEL and multicentric Castleman disease (MCD. In the infected host cell KSHV displays two modes of infection, the latency and productive viral replication phases, involving extensive viral DNA replication and gene expression. A sustained balance between latency and reactivation to the productive infection state is essential for viral persistence and KSHV pathogenesis. Our study demonstrates that the KSHV v-cyclin and cellular CDK6 kinase phosphorylate NPM on threonine 199 (Thr199 in de novo and naturally KSHV-infected cells and that NPM is phosphorylated to the same site in primary KS tumors. Furthermore, v-cyclin-mediated phosphorylation of NPM engages the interaction between NPM and the latency-associated nuclear antigen LANA, a KSHV-encoded repressor of viral lytic replication. Strikingly, depletion of NPM in PEL cells leads to viral reactivation, and production of new infectious virus particles. Moreover, the phosphorylation of NPM negatively correlates with the level of spontaneous viral reactivation in PEL cells. This work demonstrates that NPM is a critical regulator of KSHV latency via functional interactions with v-cyclin and LANA.

  1. Phase-dependent modulation of short latency cutaneous reflexes during walking in man.

    NARCIS (Netherlands)

    Baken, B.C.M.; Dietz, V.; Duysens, J.E.J.

    2005-01-01

    In reduced animal preparation (cat fictive locomotion) most of our knowledge on the phase-dependent modulation of cutaneous reflexes concerns early- (P1 responses) rather than medium-latency (P2) responses. In contrast, in humans, virtually only P2 responses have been studied because P1 responses ar

  2. Myeloid dendritic cells induce HIV-1 latency in non-proliferating CD4+ T cells.

    Science.gov (United States)

    Evans, Vanessa A; Kumar, Nitasha; Filali, Ali; Procopio, Francesco A; Yegorov, Oleg; Goulet, Jean-Philippe; Saleh, Suha; Haddad, Elias K; da Fonseca Pereira, Candida; Ellenberg, Paula C; Sekaly, Rafick-Pierre; Cameron, Paul U; Lewin, Sharon R

    2013-01-01

    Latently infected resting CD4(+) T cells are a major barrier to HIV cure. Understanding how latency is established, maintained and reversed is critical to identifying novel strategies to eliminate latently infected cells. We demonstrate here that co-culture of resting CD4(+) T cells and syngeneic myeloid dendritic cells (mDC) can dramatically increase the frequency of HIV DNA integration and latent HIV infection in non-proliferating memory, but not naïve, CD4(+) T cells. Latency was eliminated when cell-to-cell contact was prevented in the mDC-T cell co-cultures and reduced when clustering was minimised in the mDC-T cell co-cultures. Supernatants from infected mDC-T cell co-cultures did not facilitate the establishment of latency, consistent with cell-cell contact and not a soluble factor being critical for mediating latent infection of resting CD4(+) T cells. Gene expression in non-proliferating CD4(+) T cells, enriched for latent infection, showed significant changes in the expression of genes involved in cellular activation and interferon regulated pathways, including the down-regulation of genes controlling both NF-κB and cell cycle. We conclude that mDC play a key role in the establishment of HIV latency in resting memory CD4(+) T cells, which is predominantly mediated through signalling during DC-T cell contact.

  3. Myeloid dendritic cells induce HIV-1 latency in non-proliferating CD4+ T cells.

    Directory of Open Access Journals (Sweden)

    Vanessa A Evans

    Full Text Available Latently infected resting CD4(+ T cells are a major barrier to HIV cure. Understanding how latency is established, maintained and reversed is critical to identifying novel strategies to eliminate latently infected cells. We demonstrate here that co-culture of resting CD4(+ T cells and syngeneic myeloid dendritic cells (mDC can dramatically increase the frequency of HIV DNA integration and latent HIV infection in non-proliferating memory, but not naïve, CD4(+ T cells. Latency was eliminated when cell-to-cell contact was prevented in the mDC-T cell co-cultures and reduced when clustering was minimised in the mDC-T cell co-cultures. Supernatants from infected mDC-T cell co-cultures did not facilitate the establishment of latency, consistent with cell-cell contact and not a soluble factor being critical for mediating latent infection of resting CD4(+ T cells. Gene expression in non-proliferating CD4(+ T cells, enriched for latent infection, showed significant changes in the expression of genes involved in cellular activation and interferon regulated pathways, including the down-regulation of genes controlling both NF-κB and cell cycle. We conclude that mDC play a key role in the establishment of HIV latency in resting memory CD4(+ T cells, which is predominantly mediated through signalling during DC-T cell contact.

  4. Auditory Middle Latency Response and Phonological Awareness in Students with Learning Disabilities.

    Science.gov (United States)

    Romero, Ana Carla Leite; Funayama, Carolina Araújo Rodrigues; Capellini, Simone Aparecida; Frizzo, Ana Claudia Figueiredo

    2015-10-01

    Introduction Behavioral tests of auditory processing have been applied in schools and highlight the association between phonological awareness abilities and auditory processing, confirming that low performance on phonological awareness tests may be due to low performance on auditory processing tests. Objective To characterize the auditory middle latency response and the phonological awareness tests and to investigate correlations between responses in a group of children with learning disorders. Methods The study included 25 students with learning disabilities. Phonological awareness and auditory middle latency response were tested with electrodes placed on the left and right hemispheres. The correlation between the measurements was performed using the Spearman rank correlation coefficient. Results There is some correlation between the tests, especially between the Pa component and syllabic awareness, where moderate negative correlation is observed. Conclusion In this study, when phonological awareness subtests were performed, specifically phonemic awareness, the students showed a low score for the age group, although for the objective examination, prolonged Pa latency in the contralateral via was observed. Negative weak to moderate correlation for Pa wave latency was observed, as was positive weak correlation for Na-Pa amplitude.

  5. Neural latencies do not explain the auditory and audio-visual flash-lag effect.

    Science.gov (United States)

    Arrighi, Roberto; Alais, David; Burr, David

    2005-11-01

    A brief flash presented physically aligned with a moving stimulus is perceived to lag behind, a well studied phenomenon termed the Flash-Lag Effect (FLE). It has been recently shown that the FLE also occurs in audition, as well as cross-modally between vision and audition. The present study has two goals: to investigate the acoustic and cross-modal FLE using a random motion technique; and to investigate whether neural latencies may account for the FLE in general. The random motion technique revealed a strong cross-modal FLE for visual motion stimuli and auditory probes, but not for the other conditions. Visual and auditory latencies for stimulus appearance and for motion were measured with three techniques: integration, temporal alignment and reaction times. All three techniques showed that a brief static acoustic stimulus is perceived more rapidly than a brief static visual stimulus, while a sound source in motion is perceived more slowly than a comparable visual stimulus. While the results of these three techniques agreed closely with each other, they were exactly opposite that required to account for the FLE by neural latencies. We conclude that neural latencies do not, in general, explain the flash-lag effect. Rather, our data suggest that neural integration times are more important.

  6. Evaluation of DECT for low latency real-time industrial control networks

    NARCIS (Netherlands)

    Das, Kallol; Havinga, Paul

    2013-01-01

    Wireless sensor networks (WSNs) have revolutionized the industrial networks by enabling wireless sensing and control to the machine parts where wiring is impossible. However, new challenges in terms of communication reliability and latency, appear with the advances in the industrial wireless control

  7. Short-latency crossed responses in the human biceps femoris muscle

    DEFF Research Database (Denmark)

    Stevenson, Andrew James Thomas; Kamavuako, Ernest Nlandu; Geertsen, Svend S.

    2015-01-01

    , indicating their existence in humans. The aim of the present study was to investigate whether short-latency crossed-spinal reflexes are present in the contralateral biceps femoris (cBF) muscle following ipsilateral knee (iKnee) joint rotations during a sitting task, where participants maintained a slight pre...

  8. An Optimized WSN Design for Latency-Critical Smart Grid Applications

    Directory of Open Access Journals (Sweden)

    Mounib Khanafer

    2017-01-01

    Full Text Available The growing popularity of the Internet of Things (IoT systems such as the smart grid, Body Area Networks (BANs, and the Intelligent Transportation System (ITS is driving Wireless Sensor Network (WSN systems to the limit in terms of abilities and performance. WSNs were initially designed for low power, low data rate, and latency-tolerant applications. However, this paradigm is changing because of the nature of the new applications. Therefore, instead of only focusing on power-efficient WSN design, researchers and industries are now developing Quality of Service (QoS protocols for WSNs. In addition to that, latency- and reliability-critical protocol designs are also becoming significantly important in WSNs. In this paper, we present an overview of some important smart grid latency-critical applications and highlight WSNs implementation challenges for these smart grid applications. Furthermore, we develop and evaluate two novel optimization models that solve for the optimum values of the end-to-end latency and power consumption in a clustered WSN given lower bounds on reliability and other network parameters.

  9. No file left behind - monitoring transfer latencies in PhEDEx

    CERN Document Server

    Ratnikova, Natalia

    2012-01-01

    The CMS experiment has to move Petabytes of data among dozens of computing centres with low latency in order to make efficient use of its resources. Transfer operations are well established to achieve the desired level of throughput, but operators lack a system to identify early on transfers that will need manual intervention to reach completion. File transfer latencies are sensitive to the underlying problems in the transfer infrastructure, and their measurement can be used as prompt trigger for preventive actions. For this reason, PhEDEx, the CMS transfer management system, has recently implemented a monitoring system to measure the transfer latencies at the level of individual files. For the first time now, the system can predict the completion time for the transfer of a data set. The operators can detect abnormal patterns in transfer latencies early, and correct the issues while the transfer is still in progress. Statistics are aggregated for blocks of files, recording a historical log to monitor the long...

  10. Without Latency: Cathode Immersions and the Neglected Practice of Xenocasting for Television and Radio

    NARCIS (Netherlands)

    Hulbert, Adam

    2015-01-01

    abstractThis paper discusses a three-year radio project Cathode Immersions, which was aired on 2SER in Sydney Australia. The audio that accompanied free-to-air television was remixed and rebroadcast in real time without latency. It explores the human and non-human aspects of the convergence of these

  11. Analysis of Latency and MAC-layer Performance for Class A LoRaWAN

    DEFF Research Database (Denmark)

    Sørensen, René Brandborg; Kim, Dong Min; Nielsen, Jimmy Jessen

    2017-01-01

    We propose analytical models that allow to investigate the performance of Long Range Wide Area Network (LoRaWAN) uplink in terms of latency, collision rate, and throughput under the constraints of the regulatory duty cycling, when assuming exponential inter-arrival times. Our models take into acc...

  12. Choice Latency as a Cue for Children's Subjective Confidence in the Correctness of Their Answers

    Science.gov (United States)

    Koriat, Asher; Ackerman, Rakefet

    2010-01-01

    Research with adults indicates that confidence in the correctness of an answer decreases as a function of the amount of time it takes to reach that answer, suggesting that people use response latency as a mnemonic cue for subjective confidence. Experiment 1 extended investigation to 2nd, 3rd and 5th graders. When children chose the answer to…

  13. Length of Latency with Preterm Premature Rupture of Membranes before 32 Weeks’ Gestation

    Science.gov (United States)

    PEACEMAN, Alan M.; LAI, Yinglei; ROUSE, Dwight J.; SPONG, Catherine Y.; MERCER, Brian M.; VARNER, Michael W.; THORP, John M.; RAMIN, Susan M.; MALONE, Fergal D.; O'SULLIVAN, Mary J.; HANKINS, Gary D.V.

    2014-01-01

    Objective To describe latency for patients with preterm premature membrane rupture (PPROM) between 24 0/7 and 31 6/7 weeks’ gestation. Study Design Secondary analysis of data collected prospectively in a multicenter clinical trial of magnesium sulfate for cerebral palsy prevention. Women with PPROM and fewer than 6 contractions per hour at enrollment who were candidates for expectant management (n=1377) were included in this analysis. Length of latency was calculated in days by subtracting the time of delivery from the time of membrane rupture. Results At each week of gestation, median latency between 24-28 weeks was similar at approximately 9 days, but was significantly shorter with PPROM at 29, 30, and 31 weeks (p<0.001). In addition, the percentage of patients remaining undelivered at 7 days and 14 days was similar for PPROM between 24-28 weeks, but decreased significantly after that. For each gestational age, the proportion of patients remaining pregnant declined in a fashion similar to exponential pattern. Conclusion Median latency after PPROM is similar from 24-28 weeks’ gestation, but shortens with PPROM at and after 29 weeks. PMID:24819145

  14. The Middle Latency Response (MLR) and Steady State Evoked Potential (SSEP) in Neonates.

    Science.gov (United States)

    1985-05-01

    antibiotics, intracranial hemorrhage, and congenital malformations . Unfortunately, the items in this list often occur in combination rather than in isolation...JOURNAL OF THE AMERICAN AUDITORY SOCIETY 5: 156-162, 1979. Yamada, 0., Kodera, K. and Yagi, T. Cochlear processes affecting wave V latency of the

  15. Latency and Accuracy Characteristics of Saccades and Corrective Saccades in Children and Adults.

    Science.gov (United States)

    Cohen, Mark E.; Ross, Leonard E.

    1978-01-01

    Examines the latency and the accuracy of adult's and children's saccades under optimal warning and no-warning conditions. Subjects were nine adults (mean age =23.7) and nine elementary school students (mean age =8.5). (Author/MP)

  16. Reversible silencing of cytomegalovirus genomes by type I interferon governs virus latency.

    Directory of Open Access Journals (Sweden)

    Franziska Dağ

    2014-02-01

    Full Text Available Herpesviruses establish a lifelong latent infection posing the risk for virus reactivation and disease. In cytomegalovirus infection, expression of the major immediate early (IE genes is a critical checkpoint, driving the lytic replication cycle upon primary infection or reactivation from latency. While it is known that type I interferon (IFN limits lytic CMV replication, its role in latency and reactivation has not been explored. In the model of mouse CMV infection, we show here that IFNβ blocks mouse CMV replication at the level of IE transcription in IFN-responding endothelial cells and fibroblasts. The IFN-mediated inhibition of IE genes was entirely reversible, arguing that the IFN-effect may be consistent with viral latency. Importantly, the response to IFNβ is stochastic, and MCMV IE transcription and replication were repressed only in IFN-responsive cells, while the IFN-unresponsive cells remained permissive for lytic MCMV infection. IFN blocked the viral lytic replication cycle by upregulating the nuclear domain 10 (ND10 components, PML, Sp100 and Daxx, and their knockdown by shRNA rescued viral replication in the presence of IFNβ. Finally, IFNβ prevented MCMV reactivation from endothelial cells derived from latently infected mice, validating our results in a biologically relevant setting. Therefore, our data do not only define for the first time the molecular mechanism of IFN-mediated control of CMV infection, but also indicate that the reversible inhibition of the virus lytic cycle by IFNβ is consistent with the establishment of CMV latency.

  17. A Scheduling Discipline for Latency and Bandwidth Guarantees in Asynchronous Network-on-Chip

    DEFF Research Database (Denmark)

    Bjerregaard, Tobias; Sparsø, Jens

    2005-01-01

    Guaranteed services (GS) are important in that they provide predictability in the complex dynamics of shared communication structures. This paper discusses the implementation of GS in asynchronous Network-on-Chip. We present a novel scheduling discipline called Asynchronous Latency Guarantee (ALG...

  18. Flash Memory Reliability: Read, Program, and Erase Latency Versus Endurance Cycling

    Science.gov (United States)

    Heidecker, Jason

    2010-01-01

    This report documents the efforts and results of the fiscal year (FY) 2010 NASA Electronic Parts and Packaging Program (NEPP) task for nonvolatile memory (NVM) reliability. This year's focus was to measure latency (read, program, and erase) of NAND Flash memories and determine how these parameters drift with erase/program/read endurance cycling.

  19. Increasing accuracy and decreasing latency during clean intermittent self-catheterization procedures with young children.

    OpenAIRE

    McComas, J J; Lalli, J S; Benavides, C.

    1999-01-01

    We examined the effects of simulation training on performance of clean intermittent self-catheterization procedures with 2 young girls. Simulation training was conducted, after which independent performance was assessed within a multiple baseline design. The training resulted in increased accuracy and decreased latency for both girls.

  20. Absolute and comparative subcutaneous bioavailability of ardeparin sodium, a low molecular weight heparin.

    Science.gov (United States)

    Troy, S; Fruncillo, R; Ozawa, T; Mammen, E; Holloway, S; Chiang, S

    1997-08-01

    Ardeparin sodium (Normiflo, Wyeth-Ayerst) is a low molecular weight heparin undergoing clinical evaluation as an antithrombotic agent. The objective of this study was to evaluate the absolute and comparative bioavailability of ardeparin following subcutaneous administration of three different formulations [two formulations of ardeparin at 10,000 anti-factor Xa (aXa) U/ml, but with different preservatives, and a 20,000 aXa U/ml formulation]. The study was conducted using a randomized 4-period crossover design (three subcutaneous treatments and one intravenous treatment) in 24 healthy subjects, and the pharmacokinetics of ardeparin were characterized by plasma anti-factor IIa (aIIa) and anti-factor Xa (aXa) activities. The mean absolute bioavailability of ardeparin based on aIIa activity ranged from 62% to 64% and the mean absolute bioavailability based on aXa activity ranged from 88% to 97%. Based on bioequivalence testing criteria, the three ardeparin formulations were bioequivalent.

  1. A new, ultra-low latency data transmission protocol for Earthquake Early Warning Systems

    Science.gov (United States)

    Hill, P.; Hicks, S. P.; McGowan, M.

    2016-12-01

    One measure used to assess the performance of Earthquake Early Warning Systems (EEWS) is the delay time between earthquake origin and issued alert. EEWS latency is dependent on a number of sources (e.g. P-wave propagation, digitisation, transmission, receiver processing, triggering, event declaration). Many regional seismic networks use the SEEDlink protocol; however, packet size is fixed to 512-byte miniSEED records, resulting in transmission latencies of >0.5 s. Data packetisation is seen as one of the main sources of delays in EEWS (Brown et al., 2011). Optimising data-logger and telemetry configurations is a cost-effective strategy to improve EEWS alert times (Behr et al., 2015). Digitisers with smaller, selectable packets can result in faster alerts (Sokos et al., 2016). We propose a new seismic protocol for regional seismic networks benefiting low-latency applications such as EEWS. The protocol, based on Güralp's existing GDI-link format is an efficient and flexible method to exchange data between seismic stations and data centers for a range of network configurations. The main principle is to stream data sample-by-sample instead of fixed-length packets to minimise transmission latency. Self-adaptive packetisation with compression maximises available telemetry bandwidth. Highly flexible metadata fields within GDI-link are compatible with existing miniSEED definitions. Data is sent as integers or floats, supporting a wide range of data formats, including discrete parameters such as Pd & τC for on-site earthquake early warning. Other advantages include: streaming station state-of-health information, instrument control, support of backfilling and fail-over strategies during telemetry outages. Based on tests carried out on the Güralp Minimus data-logger, we show our new protocol can reduce transmission latency to as low as 1 ms. The low-latency protocol is currently being implemented with common processing packages. The results of these tests will help to

  2. Absolute gravimetry - for monitoring climate change and geodynamics in Greenland

    DEFF Research Database (Denmark)

    Nielsen, Jens Emil

    with the GPS data, it is possible to separate the different signals. The method used in this study is absolute gravimetry. An absolute gravimeter of the A10 type has been purchased by DTU Space for this purpose. This instrument can measure gravity changes as small as 6µGal (= 60nm=s2), which provides....... The time allocated for a PhD project is not sufficient to gather enough data for an elaborated analysis of the different signals which can be detected in Greenland. However, as will be presented in this thesis, the preliminary results indicate interesting possibilities for the use of absolute gravimetry...

  3. An All Fiber White Light Interferometric Absolute Temperature Measurement System

    Directory of Open Access Journals (Sweden)

    Jeonggon Harrison Kim

    2008-11-01

    Full Text Available Recently the author of this article proposed a new signal processing algorithm for an all fiber white light interferometer. In this article, an all fiber white light interferometric absolute temperature measurement system is presented using the previously proposed signal processing algorithm. Stability and absolute temperature measurement were demonstrated. These two tests demonstrated the feasibility of absolute temperature measurement with an accuracy of 0.015 fringe and 0.0005 fringe, respectively. A hysteresis test from 373K to 873K was also presented. Finally, robustness of the sensor system towards laser diode temperature drift, AFMZI temperature drift and PZT non-linearity was demonstrated.

  4. Tree Rings and Volcanic Eruptions: Reviewing the Potential of Dendrochemistry for the Absolute Dating of Past Volcanism

    Science.gov (United States)

    Pearson, C.; Manning, S. W.; Coleman, M.; Jarvis, K.

    2003-12-01

    Investigations of volcanic impact on human society and the environment are presently restrained by a lack of secure absolute dates for eruptions prior to the last few hundred years. The degree of impact and recovery, and the scope of any sociological repercussions, can only be fully explored if working from a precise, known, starting point and against a secure absolute timescale. A potential means to high resolution dating for the majority of the Holocene lies with globally available, absolutely dated tree ring chronologies. Many of these have been shown to record short term climatic alterations in periods following volcanic eruptions of known or approximate date. This argument however, has been based on an apparent correlation between the dates of specific tree ring growth anomalies and the dates of a number of eruptions in the recent historical period. The statistical correlation is less than decisive and the exact volcano-climate-tree growth linkage is by no means universally agreed. It has been suggested that a potential means to solve this problem and to attach absolute dates to volcanic eruptions via tree rings may lie in the chemistry of the annual woody increment. This paper assesses the potential of conventional Inductively Coupled Plasma Mass Spectrometry (ICP-MS) versus laser ablation ICP-MS (LA-ICP-MS) in terms of exploring this research objective. It also reviews the prospects for a dendrochemical resolution to the problem of attributing an absolute date to the volcanic eruptions of prehistory.

  5. Absolute Calibration of Proportional Counter Based Fast Pulsed Neutron Detectors with Resolution Below 105 neutron/pulse

    Science.gov (United States)

    Tarifeño-Saldivia, A.; Mayer, R. E.; Pavez, C.; Soto, L.

    2014-05-01

    A method for absolute calibration of proportional counters for pulsed fast neutrons is presented. The method is based on the use of an isotopic standard source and development of a model for counting detected events from area of a signal compounded by single piled up neutron pulses. Effects of detection counting statistics and electrical background noise are also considered. The method is applied in detectors used for D-D neutron yield measurements in low emission plasma focus devices.

  6. Plasma turbulence

    Energy Technology Data Exchange (ETDEWEB)

    Horton, W. [Univ. of Texas, Austin, TX (United States). Inst. for Fusion Studies; Hu, G. [Globalstar LP, San Jose, CA (United States)

    1998-07-01

    The origin of plasma turbulence from currents and spatial gradients in plasmas is described and shown to lead to the dominant transport mechanism in many plasma regimes. A wide variety of turbulent transport mechanism exists in plasmas. In this survey the authors summarize some of the universally observed plasma transport rates.

  7. LATENCY DETERMINATION AND COMPENSATION IN REAL-TIME GNSS/INS INTEGRATED NAVIGATION SYSTEMS

    Directory of Open Access Journals (Sweden)

    P. D. Solomon

    2012-09-01

    Full Text Available Unmanned Aerial Vehicle (UAV technology is now commonplace in many defence and civilian environments. However, the high cost of owning and operating a sophisticated UAV has slowed their adoption in many commercial markets. Universities and research groups are actively experimenting with UAVs to further develop the technology, particularly for automated flying operations. The two main UAV platforms used are fixed-wing and helicopter. Helicopter-based UAVs offer many attractive features over fixed-wing UAVs, including vertical take-off, the ability to loiter, and highly dynamic flight. However the control and navigation of helicopters are significantly more demanding than those of fixed-wing UAVs and as such require a high bandwidth real-time Position, Velocity, Attitude (PVA navigation system. In practical Real-Time Navigation Systems (RTNS there are delays in the processing of the GNSS data prior to the fusion of the GNSS data with the INS measurements. This latency must be compensated for otherwise it degrades the solution of the navigation filter. This paper investigates the effect of latency in the arrival time of the GNSS data in a RTNS. Several test drives and flights were conducted with a low-cost RTNS, and compared with a high quality GNSS/INS solution. A technique for the real-time, automated and accurate estimation of the GNSS latency in low-cost systems was developed and tested. The latency estimates were then verified through cross-correlation with the time-stamped measurements from the reference system. A delayed measurement Extended Kalman Filter was then used to allow for the real-time fusing of the delayed measurements, and then a final system developed for on-the-fly measurement and compensation of GNSS latency in a RTNS.

  8. Latency Determination and Compensation in Real-Time Gnss/ins Integrated Navigation Systems

    Science.gov (United States)

    Solomon, P. D.; Wang, J.; Rizos, C.

    2011-09-01

    Unmanned Aerial Vehicle (UAV) technology is now commonplace in many defence and civilian environments. However, the high cost of owning and operating a sophisticated UAV has slowed their adoption in many commercial markets. Universities and research groups are actively experimenting with UAVs to further develop the technology, particularly for automated flying operations. The two main UAV platforms used are fixed-wing and helicopter. Helicopter-based UAVs offer many attractive features over fixed-wing UAVs, including vertical take-off, the ability to loiter, and highly dynamic flight. However the control and navigation of helicopters are significantly more demanding than those of fixed-wing UAVs and as such require a high bandwidth real-time Position, Velocity, Attitude (PVA) navigation system. In practical Real-Time Navigation Systems (RTNS) there are delays in the processing of the GNSS data prior to the fusion of the GNSS data with the INS measurements. This latency must be compensated for otherwise it degrades the solution of the navigation filter. This paper investigates the effect of latency in the arrival time of the GNSS data in a RTNS. Several test drives and flights were conducted with a low-cost RTNS, and compared with a high quality GNSS/INS solution. A technique for the real-time, automated and accurate estimation of the GNSS latency in low-cost systems was developed and tested. The latency estimates were then verified through cross-correlation with the time-stamped measurements from the reference system. A delayed measurement Extended Kalman Filter was then used to allow for the real-time fusing of the delayed measurements, and then a final system developed for on-the-fly measurement and compensation of GNSS latency in a RTNS.

  9. The amblyopic eye in subjects with anisometropia show increased saccadic latency in the delayed saccade task

    Directory of Open Access Journals (Sweden)

    Maciej ePerdziak

    2014-10-01

    Full Text Available The term amblyopia is used to describe reduced visual function in one eye (or both eyes, though not so often which cannot be fully improved by refractive correction and explained by the organic cause observed during regular eye examination. This developmental disorder of spatial vision affects about 2-5% of the population and is associated with abnormal visual experience (e.g. anisometropia, strabismus during infancy or early childhood. Several studies have shown prolongation of saccadic latency time in amblyopic eye. In our opinion, study of saccadic latency in the context of central vision deficits assessment, should be based on central retina stimulation. For this reason, we proposed saccade delayed task. It requires inhibitory processing for maintaining fixation on the central target until it disappears – what constitutes the GO signal for saccade. The experiment consisted of 100 trials for each eye and was performed under two viewing conditions: monocular amblyopic / non-dominant eye and monocular dominant eye. We examined saccadic latency in 16 subjects (mean age 30±11 years with anisometropic amblyopia (two subjects had also microtropia and in 17 control subjects (mean age 28±8 years. Participants were instructed to look at central (fixation target and when it disappears, to make the saccade toward the periphery (10 deg as fast as possible, either left or the right target. The study results have proved the significant difference in saccadic latency between the amblyopic (mean 262±48 ms and dominant (mean 237±45 ms eye, in anisometropic group. In the control group, the saccadic latency for dominant (mean 226±32ms and non-dominant (mean 230±29 ms eye was not significantly different.By the use of LATER (Linear Approach to the Threshold with Ergodic Rate decision model we interpret our findings as a decrease in accumulation of visual information acquired by means of central (affected retina in subjects with anisometropic amblyopia.

  10. Tap Arduino: An Arduino microcontroller for low-latency auditory feedback in sensorimotor synchronization experiments.

    Science.gov (United States)

    Schultz, Benjamin G; van Vugt, Floris T

    2016-12-01

    Timing abilities are often measured by having participants tap their finger along with a metronome and presenting tap-triggered auditory feedback. These experiments predominantly use electronic percussion pads combined with software (e.g., FTAP or Max/MSP) that records responses and delivers auditory feedback. However, these setups involve unknown latencies between tap onset and auditory feedback and can sometimes miss responses or record multiple, superfluous responses for a single tap. These issues may distort measurements of tapping performance or affect the performance of the individual. We present an alternative setup using an Arduino microcontroller that addresses these issues and delivers low-latency auditory feedback. We validated our setup by having participants (N = 6) tap on a force-sensitive resistor pad connected to the Arduino and on an electronic percussion pad with various levels of force and tempi. The Arduino delivered auditory feedback through a pulse-width modulation (PWM) pin connected to a headphone jack or a wave shield component. The Arduino's PWM (M = 0.6 ms, SD = 0.3) and wave shield (M = 2.6 ms, SD = 0.3) demonstrated significantly lower auditory feedback latencies than the percussion pad (M = 9.1 ms, SD = 2.0), FTAP (M = 14.6 ms, SD = 2.8), and Max/MSP (M = 15.8 ms, SD = 3.4). The PWM and wave shield latencies were also significantly less variable than those from FTAP and Max/MSP. The Arduino missed significantly fewer taps, and recorded fewer superfluous responses, than the percussion pad. The Arduino captured all responses, whereas at lower tapping forces, the percussion pad missed more taps. Regardless of tapping force, the Arduino outperformed the percussion pad. Overall, the Arduino is a high-precision, low-latency, portable, and affordable tool for auditory experiments.

  11. Channel noise effects on first spike latency of a stochastic Hodgkin-Huxley neuron

    Science.gov (United States)

    Maisel, Brenton; Lindenberg, Katja

    2017-02-01

    While it is widely accepted that information is encoded in neurons via action potentials or spikes, it is far less understood what specific features of spiking contain encoded information. Experimental evidence has suggested that the timing of the first spike may be an energy-efficient coding mechanism that contains more neural information than subsequent spikes. Therefore, the biophysical features of neurons that underlie response latency are of considerable interest. Here we examine the effects of channel noise on the first spike latency of a Hodgkin-Huxley neuron receiving random input from many other neurons. Because the principal feature of a Hodgkin-Huxley neuron is the stochastic opening and closing of channels, the fluctuations in the number of open channels lead to fluctuations in the membrane voltage and modify the timing of the first spike. Our results show that when a neuron has a larger number of channels, (i) the occurrence of the first spike is delayed and (ii) the variation in the first spike timing is greater. We also show that the mean, median, and interquartile range of first spike latency can be accurately predicted from a simple linear regression by knowing only the number of channels in the neuron and the rate at which presynaptic neurons fire, but the standard deviation (i.e., neuronal jitter) cannot be predicted using only this information. We then compare our results to another commonly used stochastic Hodgkin-Huxley model and show that the more commonly used model overstates the first spike latency but can predict the standard deviation of first spike latencies accurately. We end by suggesting a more suitable definition for the neuronal jitter based upon our simulations and comparison of the two models.

  12. Brain targeted transcranial administration of diazepam and shortening of sleep latency in healthy human volunteers

    Directory of Open Access Journals (Sweden)

    W Pathirana

    2011-01-01

    Full Text Available Application of medicated oils on scalp had been practiced for centuries in the Ayurvedic system of medicine in diseases associated with the central nervous system. It is possible that the effectiveness of the therapy may be a result of targeted delivery of active compounds to the brain transcranially. Evidence also comes from two previous studies with positive results on brain targeted transcranial delivery of methadone base and diazepam on rat models. Possibility of transcranial drug delivery was investigated in healthy human volunteers using electroencephalography techniques by assessing the ability of transcranially administered diazepam in bringing about β activity in the electroencephalographic wave patterns and shortening of the sleep latency period. Non polar drug molecules dissolved in a non-aqueous sesame oil based vehicle is a significant feature in the transcranial dosage design. The study was under taken in two phases. In the Phase-I study scalp application of a single dose of 2 mg/3 ml of the oil was employed and in the Phase-II study repeat application of three doses 24 h apart were employed. Sleep latency changes were monitored with Multiple Sleep Latency Tests with 5 naps employing the standard electroencephalography, electroocculography and electromyography electrodes. Sleep onset was identified with the first epoch of any sleep stage non rapid eye movement 1, 2, 3, 4 or rapid eye movement using electroencephalography, electroocculography and electromyography criteria. In both phases of the study there was significant reduction in the sleep latencies. It was much more pronounced in the Phase-II study. None of the subjects however displayed beta activity in the electroencephalography. Sleep latency reduction following scalp application in both the phases are suggestive of transcranial migration of diazepam molecules to the receptor sites of the nerve tissue of the brain eliciting its pharmacological effect of sedation

  13. Treating Excessively Slow Responding of a Young Man with Asperger Syndrome Using Differential Reinforcement of Short Response Latencies

    Science.gov (United States)

    Tiger, Jeffrey H.; Bouxsein, Kelly J.; Fisher, Wayne W.

    2007-01-01

    Fjellstedt and Sulzer-Azaroff (1973) used differential reinforcement of short latencies to decrease a child's latency to comply with instructions. We replicated this contingency with a young man diagnosed with Asperger syndrome across two tasks (question answering and math problem solving). We added a differential reinforcement contingency to…

  14. Significance of absolute energy scale for physics at BESⅢ

    Institute of Scientific and Technical Information of China (English)

    FU Cheng-Dong; MO Xiao-Hu

    2008-01-01

    The effects of absolute energy calibration on BESⅢ physics are discussed in detail,which mainly involve the effects on τ mass measurement,cross section scan measurement,and generic error determination in other measurements.

  15. Producing Absolute Truth: CSI Science as Wishful Thinking

    National Research Council Canada - National Science Library

    Kruse, Corinna

    2010-01-01

    ...). I argue that CSI science, in delivering an absolute “truth” about how and by whom crimes have been committed, is equated with justice, effectively superseding nonfictional forensic science as well as nonfictional judicature as a whole...

  16. Changes in Absolute Sea Level Along U.S. Coasts

    Data.gov (United States)

    U.S. Environmental Protection Agency — This map shows changes in absolute sea level from 1960 to 2016 based on satellite measurements. Data were adjusted by applying an inverted barometer (air pressure)...

  17. Absolute position total internal reflection microscopy with an optical tweezer

    National Research Council Canada - National Science Library

    Lulu Liu; Alexander Woolf; Alejandro W. Rodriguez; Federico Capasso

    2014-01-01

    .... We show that by making only simple modifications to the basic TIRM sensing setup and procedure, a probe particle's absolute position relative to a dielectric interface may be known with better than...

  18. Monochromator-Based Absolute Calibration of Radiation Thermometers

    Science.gov (United States)

    Keawprasert, T.; Anhalt, K.; Taubert, D. R.; Hartmann, J.

    2011-08-01

    A monochromator integrating-sphere-based spectral comparator facility has been developed to calibrate standard radiation thermometers in terms of the absolute spectral radiance responsivity, traceable to the PTB cryogenic radiometer. The absolute responsivity calibration has been improved using a 75 W xenon lamp with a reflective mirror and imaging optics to a relative standard uncertainty at the peak wavelength of approximately 0.17 % ( k = 1). Via a relative measurement of the out-of-band responsivity, the spectral responsivity of radiation thermometers can be fully characterized. To verify the calibration accuracy, the absolutely calibrated radiation thermometer is used to measure Au and Cu freezing-point temperatures and then to compare the obtained results with the values obtained by absolute methods, resulting in T - T 90 values of +52 mK and -50 mK for the gold and copper fixed points, respectively.

  19. Preparation of an oakmoss absolute with reduced allergenic potential.

    Science.gov (United States)

    Ehret, C; Maupetit, P; Petrzilka, M; Klecak, G

    1992-06-01

    Synopsis Oakmoss absolute, an extract of the lichen Evernia prunastri, is known to cause allergenic skin reactions due to the presence of certain aromatic aldehydes such as atranorin, chloratranorin, ethyl hematommate and ethyl chlorohematommate. In this paper it is shown that treatment of Oakmoss absolute with amino acids such as lysine and/or leucine, lowers considerably the content of these allergenic constituents including atranol and chloratranol. The resulting Oakmoss absolute, which exhibits an excellent olfactive quality, was tested extensively in comparative studies on guinea pigs and on man. The results of the Guinea Pig Maximization Test (GPMT) and Human Repeated Insult Patch Test (HRIPT) indicate that, in comparison with the commercial test sample, the allergenicity of this new quality of Oakmoss absolute was considerably reduced, and consequently better skin tolerance of this fragrance for man was achieved.

  20. Restricted TET2 Expression in Germinal Center Type B Cells Promotes Stringent Epstein-Barr Virus Latency.

    Science.gov (United States)

    Wille, Coral K; Li, Yangguang; Rui, Lixin; Johannsen, Eric C; Kenney, Shannon C

    2017-03-01

    Epstein-Barr virus (EBV) latently infects normal B cells and contributes to the development of certain human lymphomas. Newly infected B cells support a highly transforming form (type III) of viral latency; however, long-term EBV infection in immunocompetent hosts is limited to B cells with a more restricted form of latency (type I) in which most viral gene expression is silenced by promoter DNA methylation. How EBV converts latency type is unclear, although it is known that type I latency is associated with a germinal center (GC) B cell phenotype, and type III latency with an activated B cell (ABC) phenotype. In this study, we have examined whether expression of TET2, a cellular enzyme that initiates DNA demethylation by converting 5-methylcytosine (5mC) into 5-hydroxymethylcytosine (5hmC), regulates EBV latency type in B cells. We found that TET2 expression is inhibited in normal GC cells and GC type lymphomas. In contrast, TET2 is expressed in normal naive B cells and ABC type lymphomas. We also demonstrate that GC type cell lines have increased 5mC levels and reduced 5hmC levels in comparison to those of ABC type lines. Finally, we show that TET2 promotes the ability of the EBV transcription factor EBNA2 to convert EBV-infected cells from type I to type III latency. These findings demonstrate that TET2 expression is repressed in GC cells independent of EBV infection and suggest that TET2 promotes type III EBV latency in B cells with an ABC or naive phenotype by enhancing EBNA2 activation of methylated EBV promoters.IMPORTANCE EBV establishes several different types of viral latency in B cells. However, cellular factors that determine whether EBV enters the highly transforming type III latency, versus the more restricted type I latency, have not been well characterized. Here we show that TET2, a cellular enzyme that initiates DNA demethylation by converting 5-methylcytosine (5mC) into 5-hydroxymethylcytosine (5hmC), regulates EBV latency type in B cells by

  1. DIAGNOSTIC TEST FOR GARCH MODELS BASED ON ABSOLUTE RESIDUAL AUTOCORRELATIONS

    Directory of Open Access Journals (Sweden)

    Farhat Iqbal

    2013-10-01

    Full Text Available In this paper the asymptotic distribution of the absolute residual autocorrelations from generalized autoregressive conditional heteroscedastic (GARCH models is derived. The correct asymptotic standard errors for the absolute residual autocorrelations are also obtained and based on these results, a diagnostic test for checking the adequacy of GARCH-type models are developed. Our results do not depend on the existence of higher moments and is therefore robust under heavy-tailed distributions.

  2. Global trends in relative and absolute wealth concentrations

    OpenAIRE

    2014-01-01

    This paper compares changes in relative and absolute wealth concentrations to establish if both processes have followed similar trajectories. The findings indicate that while the level of relative wealth concentration has increased recently, it is not extraordinarily high in an historical perspective. On the contrary, the level of absolute wealth concentration is most likely higher than that previously occurred because of the increase in the wealth holdings and population size of high net wor...

  3. Spectra of absolute instruments from the WKB approximation

    CERN Document Server

    Tyc, Tomas

    2013-01-01

    We calculate frequency spectra of absolute optical instruments using the WKB approximation. The resulting eigenfrequencies approximate the actual values very accurately, in some cases they even give the exact values. Our calculations confirm results obtained previously by a completely different method. In particular, the eigenfrequencies of absolute instruments form tight groups that are almost equidistantly spaced. We demonstrate our method and its results on several examples.

  4. DIAGNOSTIC TEST FOR GARCH MODELS BASED ON ABSOLUTE RESIDUAL AUTOCORRELATIONS

    Directory of Open Access Journals (Sweden)

    Farhat Iqbal

    2013-10-01

    Full Text Available In this paper the asymptotic distribution of the absolute residual autocorrelations from generalized autoregressive conditional heteroscedastic (GARCH models is derived. The correct asymptotic standard errors for the absolute residual autocorrelations are also obtained and based on these results, a diagnostic test for checking the adequacy of GARCH-type models are developed. Our results do not depend on the existence of higher moments and is therefore robust under heavy-tailed distributions.

  5. Absolute Free Energies for Biomolecules in Implicit or Explicit Solvent

    Science.gov (United States)

    Berryman, Joshua T.; Schilling, Tanja

    Methods for absolute free energy calculation by alchemical transformation of a quantitative model to an analytically tractable one are discussed. These absolute free energy methods are placed in the context of other methods, and an attempt is made to describe the best practice for such calculations given the current state of the art. Calculations of the equilibria between the four free energy basins of the dialanine molecule and the two right- and left-twisted basins of DNA are discussed as examples.

  6. Absolute cardiovascular risk in a Fiji medical zone.

    Science.gov (United States)

    Gyaneshwar, Rajat; Naidu, Swaran; Raban, Magdalena Z; Naidu, Sheetal; Linhart, Christine; Morrell, Stephen; Tukana, Isimeli; Taylor, Richard

    2016-02-09

    The population of Fiji has experienced emergence of non-communicable disease (NCD) and a plateau in life expectancy over the past 20 years. A mini-STEPS survey (n = 2765) was conducted in Viseisei in Western Fiji to assess NCD risk factors (RFs) in i-Taukei (Melanesians) and those of Indian descent aged 25-64 years (response 73 %). Hypertension (HT) was defined as systolic blood pressure (BP) ≥140 mmHg or diastolic BP ≥90 mmHg or on medication for HT; type 2 diabetes mellitus (T2DM) as fasting plasma glucose ≥7.0 mmol/L or on medication for T2DM; and obesity as a body mass index (kilograms/height(metres)(2)) ≥30. Data were age-adjusted to 2007 Fiji Census. Associations between RFs and ethnicity/education were investigated. Comparisons with Fiji STEPS surveys were undertaken, and the absolute risk of a cardiovascular disease (CVD) event/death in 10 years was estimated from multiple RF charts. NCD/RFs increased with age except excessive alcohol intake and daily smoking (women) which declined. Daily smoking was higher in men 33 % (95 % confidence interval: 31-36) than women 14 % (12-116); women were more obese 40 % (37-43) than men 23 % (20-26); HT was similar in men 37 % (34-40) and women 34 % (31-36), as was T2DM in men 15 % (13-17) and women 17 % (15-19). i-Taukei men had an odds ratio (OR) of 0.41 (0.28-0.58) for T2DM compared to Indians (1.00); and i-Taukei (both sexes) had a higher OR for obesity and low fruit/vegetable intake, daily smoking, excessive alcohol intake and HT in females. Increasing education correlated with lesser smoking, but with higher obesity and lower fruit/vegetable intake. Compared to the 2011 Fiji STEPS survey, no significant differences were evident in obesity, HT or T2DM prevalences. The proportion (40-64 years) classified at high or very high risk (≥20 %) of a CVD event/death (over 10 years) based on multiple RFs was 8.3 % for men (8.1 % i-Taukei, 8.5 % Indian), and 6.7 % for women (7.9 % i-Taukei, 6.0 % Indian). The results

  7. Group II muscle afferents probably contribute to the medium latency soleus stretch reflex during walking in humans

    DEFF Research Database (Denmark)

    Grey, Michael James; Ladouceur, Michel; Andersen, Jacob B.

    2001-01-01

    1. The objective of this study was to determine which afferents contribute to the medium latency response of the soleus stretch reflex resulting from an unexpected perturbation during human walking. 2. Fourteen healthy subjects walked on a treadmill at approximately 3.5 km h(-1) with the left ankle...... component (P = 0.004), whereas the medium latency component was unchanged (P = 0.437). 6. Two hours after the ingestion of tizanidine, an alpha(2)-adrenergic receptor agonist known to selectively depress the transmission in the group II afferent pathway, the medium latency reflex was strongly depressed (P...... = 0.007), whereas the short latency component was unchanged (P = 0.653). 7. An ankle block with lidocaine hydrochloride was performed to suppress the cutaneous afferents of the foot and ankle. Neither the short (P = 0.453) nor medium (P = 0.310) latency reflexes were changed. 8. Our results support...

  8. Plasma harmonics

    CERN Document Server

    Ganeev, Rashid A

    2014-01-01

    Preface; Why plasma harmonics? A very brief introduction Early stage of plasma harmonic studies - hopes and frustrations New developments in plasma harmonics studies: first successes Improvements of plasma harmonics; Theoretical basics of plasma harmonics; Basics of HHG Harmonic generation in fullerenes using few-cycle pulsesVarious approaches for description of observed peculiarities of resonant enhancement of a single harmonic in laser plasmaTwo-colour pump resonance-induced enhancement of odd and even harmonics from a tin plasmaCalculations of single harmonic generation from Mn plasma;Low-o

  9. HIV Latency

    OpenAIRE

    Robert F. Siliciano; Greene, Warner C.

    2011-01-01

    HIV-1 can establish a state of latent infection at the level of individual T cells. Latently infected cells are rare in vivo and appear to arise when activated CD4+ T cells, the major targets cells for HIV-1, become infected and survive long enough to revert back to a resting memory state, which is nonpermissive for viral gene expression. Because latent virus resides in memory T cells, it persists indefinitely even in patients on potent antiretroviral therapy. This latent reservoir is recogni...

  10. Obesity-mediated regulation of HGF/c-Met is associated with reduced basal-like breast cancer latency in parous mice.

    Directory of Open Access Journals (Sweden)

    Sneha Sundaram

    Full Text Available It is widely thought that pregnancy reduces breast cancer risk, but this lacks consideration of breast cancer subtypes. While a full term pregnancy reduces risk for estrogen receptor positive (ER+ and luminal breast cancers, parity is associated with increased risk of basal-like breast cancer (BBC subtype. Basal-like subtypes represent less than 10% of breast cancers and are highly aggressive, affecting primarily young, African American women. Our previous work demonstrated that high fat diet-induced obesity in nulliparous mice significantly blunted latency in C3(1-TAg mice, a model of BBC, potentially through the hepatocyte growth factor (HGF/c-Met oncogenic pathway. Experimental studies have examined parity and obesity individually, but to date, the joint effects of parity and obesity have not been studied. We investigated the role of obesity in parous mice on BBC. Parity alone dramatically blunted tumor latency compared to nulliparous controls with no effects on tumor number or growth, while obesity had only a minor role in further reducing latency. Obesity-associated metabolic mediators and hormones such as insulin, estrogen, and progesterone were not significantly regulated by obesity. Plasma IL-6 was also significantly elevated by obesity in parous mice. We have previously reported a potential role for stromal-derived hepatocyte growth factor (HGF via its cognate receptor c-Met in the etiology of obesity-induced BBC tumor onset and in both human and murine primary coculture models of BBC-aggressiveness. Obesity-associated c-Met concentrations were 2.5-fold greater in normal mammary glands of parous mice. Taken together, our studies demonstrate that, parity in C3(1-TAg mice dramatically reduced BBC latency compared to nulliparous mice. In parous mice, c-Met is regulated by obesity in unaffected mammary gland and is associated with tumor onset. C3(1-TAg mice recapitulate epidemiologic findings such that parity drives increased BBC risk and

  11. Obesity-Mediated Regulation of HGF/c-Met Is Associated with Reduced Basal-Like Breast Cancer Latency in Parous Mice

    Science.gov (United States)

    Sundaram, Sneha; Freemerman, Alex J.; Galanko, Joseph A.; McNaughton, Kirk K.; Bendt, Katharine M.; Darr, David B.; Troester, Melissa A.; Makowski, Liza

    2014-01-01

    It is widely thought that pregnancy reduces breast cancer risk, but this lacks consideration of breast cancer subtypes. While a full term pregnancy reduces risk for estrogen receptor positive (ER+) and luminal breast cancers, parity is associated with increased risk of basal-like breast cancer (BBC) subtype. Basal-like subtypes represent less than 10% of breast cancers and are highly aggressive, affecting primarily young, African American women. Our previous work demonstrated that high fat diet-induced obesity in nulliparous mice significantly blunted latency in C3(1)-TAg mice, a model of BBC, potentially through the hepatocyte growth factor (HGF)/c-Met oncogenic pathway. Experimental studies have examined parity and obesity individually, but to date, the joint effects of parity and obesity have not been studied. We investigated the role of obesity in parous mice on BBC. Parity alone dramatically blunted tumor latency compared to nulliparous controls with no effects on tumor number or growth, while obesity had only a minor role in further reducing latency. Obesity-associated metabolic mediators and hormones such as insulin, estrogen, and progesterone were not significantly regulated by obesity. Plasma IL-6 was also significantly elevated by obesity in parous mice. We have previously reported a potential role for stromal-derived hepatocyte growth factor (HGF) via its cognate receptor c-Met in the etiology of obesity-induced BBC tumor onset and in both human and murine primary coculture models of BBC-aggressiveness. Obesity-associated c-Met concentrations were 2.5-fold greater in normal mammary glands of parous mice. Taken together, our studies demonstrate that, parity in C3(1)-TAg mice dramatically reduced BBC latency compared to nulliparous mice. In parous mice, c-Met is regulated by obesity in unaffected mammary gland and is associated with tumor onset. C3(1)-TAg mice recapitulate epidemiologic findings such that parity drives increased BBC risk and potential

  12. Obesity-mediated regulation of HGF/c-Met is associated with reduced basal-like breast cancer latency in parous mice.

    Science.gov (United States)

    Sundaram, Sneha; Freemerman, Alex J; Galanko, Joseph A; McNaughton, Kirk K; Bendt, Katharine M; Darr, David B; Troester, Melissa A; Makowski, Liza

    2014-01-01

    It is widely thought that pregnancy reduces breast cancer risk, but this lacks consideration of breast cancer subtypes. While a full term pregnancy reduces risk for estrogen receptor positive (ER+) and luminal breast cancers, parity is associated with increased risk of basal-like breast cancer (BBC) subtype. Basal-like subtypes represent less than 10% of breast cancers and are highly aggressive, affecting primarily young, African American women. Our previous work demonstrated that high fat diet-induced obesity in nulliparous mice significantly blunted latency in C3(1)-TAg mice, a model of BBC, potentially through the hepatocyte growth factor (HGF)/c-Met oncogenic pathway. Experimental studies have examined parity and obesity individually, but to date, the joint effects of parity and obesity have not been studied. We investigated the role of obesity in parous mice on BBC. Parity alone dramatically blunted tumor latency compared to nulliparous controls with no effects on tumor number or growth, while obesity had only a minor role in further reducing latency. Obesity-associated metabolic mediators and hormones such as insulin, estrogen, and progesterone were not significantly regulated by obesity. Plasma IL-6 was also significantly elevated by obesity in parous mice. We have previously reported a potential role for stromal-derived hepatocyte growth factor (HGF) via its cognate receptor c-Met in the etiology of obesity-induced BBC tumor onset and in both human and murine primary coculture models of BBC-aggressiveness. Obesity-associated c-Met concentrations were 2.5-fold greater in normal mammary glands of parous mice. Taken together, our studies demonstrate that, parity in C3(1)-TAg mice dramatically reduced BBC latency compared to nulliparous mice. In parous mice, c-Met is regulated by obesity in unaffected mammary gland and is associated with tumor onset. C3(1)-TAg mice recapitulate epidemiologic findings such that parity drives increased BBC risk and potential

  13. A comparison of herpes simplex virus type 1 and varicella-zoster virus latency and reactivation

    Science.gov (United States)

    Kennedy, Peter G. E.; Rovnak, Joel; Badani, Hussain

    2015-01-01

    Herpes simplex virus type 1 (HSV-1; human herpesvirus 1) and varicella-zoster virus (VZV; human herpesvirus 3) are human neurotropic alphaherpesviruses that cause lifelong infections in ganglia. Following primary infection and establishment of latency, HSV-1 reactivation typically results in herpes labialis (cold sores), but can occur frequently elsewhere on the body at the site of primary infection (e.g. whitlow), particularly at the genitals. Rarely, HSV-1 reactivation can cause encephalitis; however, a third of the cases of HSV-1 encephalitis are associated with HSV-1 primary infection. Primary VZV infection causes varicella (chickenpox) following which latent virus may reactivate decades later to produce herpes zoster (shingles), as well as an increasingly recognized number of subacute, acute and chronic neurological conditions. Following primary infection, both viruses establish a latent infection in neuronal cells in human peripheral ganglia. However, the detailed mechanisms of viral latency and reactivation have yet to be unravelled. In both cases latent viral DNA exists in an ‘end-less’ state where the ends of the virus genome are joined to form structures consistent with unit length episomes and concatemers, from which viral gene transcription is restricted. In latently infected ganglia, the most abundantly detected HSV-1 RNAs are the spliced products originating from the primary latency associated transcript (LAT). This primary LAT is an 8.3 kb unstable transcript from which two stable (1.5 and 2.0 kb) introns are spliced. Transcripts mapping to 12 VZV genes have been detected in human ganglia removed at autopsy; however, it is difficult to ascribe these as transcripts present during latent infection as early-stage virus reactivation may have transpired in the post-mortem time period in the ganglia. Nonetheless, low-level transcription of VZV ORF63 has been repeatedly detected in multiple ganglia removed as close to death as possible. There is

  14. Reduced complexity and latency for a massive MIMO system using a parallel detection algorithm

    Directory of Open Access Journals (Sweden)

    Shoichi Higuchi

    2017-09-01

    Full Text Available In recent years, massive MIMO systems have been widely researched to realize high-speed data transmission. Since massive MIMO systems use a large number of antennas, these systems require huge complexity to detect the signal. In this paper, we propose a novel detection method for massive MIMO using parallel detection with maximum likelihood detection with QR decomposition and M-algorithm (QRM-MLD to reduce the complexity and latency. The proposed scheme obtains an R matrix after permutation of an H matrix and QR decomposition. The R matrix is also eliminated using a Gauss–Jordan elimination method. By using a modified R matrix, the proposed method can detect the transmitted signal using parallel detection. From the simulation results, the proposed scheme can achieve a reduced complexity and latency with a little degradation of the bit error rate (BER performance compared with the conventional method.

  15. Short-latency crossed responses in the human biceps femoris muscle

    DEFF Research Database (Denmark)

    Stevenson, Andrew James Thomas; Kamavuako, Ernest Nlandu; Geertsen, Svend Sparre;

    Ipsilateral knee (iKnee) joint rotations in seated humans elicit short-latency crossed spinal reflexes in the contralateral biceps femoris (cBF) muscle (Stevenson et al., 2012). The short-latency cBF reflexes were inhibitory following iKnee extension perturbations, and facilitatory following...... of MUs. 11 seated participants (mean age 25 ± 5 years) performed a voluntary isometric knee extension with the ipsilateral leg and contralateral knee flexion to 10% of MVC. Surface EMG was recorded bilaterally from the BF and rectus femoris, and iEMG from the cBF. A mechanical actuator (MTS......-Systems Corporation) imposed iKnee flexion or extension perturbations (8° and 150°/s) in blocks of 60 trials. iEMG data for flexion and extension perturbations were decomposed (EMGLAB, McGill et al., 2005) into constituent MU action potentials (APs). The total number of APs was quantified using a 10 ms window...

  16. Group Ia afferents contribute to short-latency interlimb reflexes in the human biceps femoris muscle

    DEFF Research Database (Denmark)

    Stevenson, Andrew James Thomas; Kamavuako, Ernest Nlandu; Geertsen, Svend Sparre

    2017-01-01

    and velocity of the iKnee rotations. Methods 11 seated participants (mean age: 25 ± 5 years) performed a voluntary isometric knee extension with the ipsilateral leg and contralateral knee flexion to 10% of maximum voluntary contraction (MVC). A mechanical actuator (MTS-Systems Corporation) imposed i...... amplitudes (4 vs. 8°) at the same 150°/s velocity (p’s > 0.08). Conclusion Because fast conducting group Ia muscle spindle afferents are sensitive to changes in muscle stretch velocity, while group II spindle afferents are sensitive to changes in amplitude (Grey et al., JPhysiol., 2001; Matthews, Trends...... Neurosci., 1991), group Ia velocity sensitive muscle spindle afferents likely contribute to the short-latency crossed spinal reflexes in the cBF muscle following iKnee joint rotations. This supports the findings for the short-latency crossed responses in the human soleus muscle (Stubbs & Mrachacz...

  17. Low-latency multi-threaded processing of neuronal signals for brain-computer interfaces

    Directory of Open Access Journals (Sweden)

    Jörg eFischer

    2014-01-01

    Full Text Available Brain-computer interfaces (BCIs require demanding numerical computations to transfer brain signals into control signals driving an external actuator. Increasing the computational performance of the BCI algorithms carrying out these calculations enables faster reaction to user inputs and allows using more demanding decoding algorithms. Here we introduce a modular and extensible software architecture with a multi-threaded signal processing pipeline suitable for BCI applications. The computational load and latency (the time that the system needs to react to user input are measured for different pipeline implementations in typical BCI applications with realistic parameter settings. We show that BCIs can benefit substantially from the proposed parallelization: firstly, by reducing the latency and secondly, by increasing the amount of recording channels and signal features that can be used for decoding beyond the amount which can be handled by a single thread. The proposed software architecture provides a simple, yet flexible solution for BCI applications.

  18. Treatment of high-latency microcapsules containing an aluminium complex with an epoxy-functionalised trialkoxysilane.

    Science.gov (United States)

    Kamiya, Kazunobu; Suzuki, Noboru

    2016-12-01

    Some aluminium complexes are excellent catalysts of cationic polymerisation and are used for low-temperature and fast-curing adhesive, used in electronic part mounting. Microencapsulation is a suitable technique for getting high latency of the catalysts and long shelf life of the adhesives. For the higher latency in a cycloaliphatic epoxy compound, the microcapsule surface which retained small amount of aluminium complex was coated with epoxy polymer and the effect was examined. From the X-ray photoelectron spectroscopic results, the surface was recognised to be sufficiently coated and the differential scanning calorimetric analyses showed that the coating did not significantly affect the low-temperature and fast-curing properties of adhesive. After storing the mixture of cycloaliphatic epoxy compound, coated microcapsules, triphenylsilanol and silane coupling agent for 48 h at room temperature, the increase in viscosity was only 0.01 Pa s, resulting in the excellent shelf life.

  19. Short latency vestibular potentials evoked by electrical round window stimulation in the guinea pig.

    Science.gov (United States)

    Bordure, P; Desmadryl, G; Uziel, A; Sans, A

    1989-11-01

    Short-latency potentials evoked by round window electrical stimulation were recorded in guinea pig by means of vertex-pinna skin electrodes using averaging techniques. Constant current shocks of 20 microseconds or 50 microseconds (25-300 microA) were used to evoke both auditory and vestibular brain-stem potentials. Pure auditory potentials, comparable to those evoked by acoustic clicks, were obtained by 20 microseconds electrical stimuli and disappeared during an auditory masking procedure made with a continuous white noise (110 dB SPL). Short latency potentials labeled V1, V2 and V3 were obtained by 50 microseconds electrical stimuli during an auditory masking procedure. This response disappeared after specific vestibular neurectomy, whereas the auditory response evoked by acoustic clicks or by electrical stimulation remained unchanged, suggesting that these latter potentials had a vestibular origin.

  20. Zinc supplementation prolongs the latency of hyperthermia-induced febrile seizures in rats.

    Science.gov (United States)

    Aydın, L; Erdem, S R; Yazıcı, C

    2016-03-01

    Some studies have shown a relationship between febrile seizures and zinc levels. The lowest dose zinc supplementation in pentylenetetrazole seizure model has a protective effect. But, zinc pretreatment has no effect in maximal electroshock model. However, it is unclear how zinc supplementation affects hyperthermia-induced febrile seizures. The aim of the present study was to investigate the effects of zinc supplementation on febrile seizures in male Sprague-Dawley rats. The rats were randomly assigned to four groups. Zinc supplementation was commenced 5 days prior to febrile seizure induction by placing the animals in a water bath at 45°C. We measured the rectal temperature and determined the febrile seizure latency, duration, and stage. In the zinc-supplemented group, both the seizure latency and the rectal temperature triggering seizure initiation were significantly higher than in the other groups. We suggest that zinc supplementation can positively modulate febrile seizure pathogenesis in rats.

  1. Summed Parallel Infinite Impulse Response (SPIIR) Filters For Low-Latency Gravitational Wave Detection

    CERN Document Server

    Hooper, Shaun; Luan, Jing; Blair, David; Chen, Yanbei; Wen, Linqing

    2011-01-01

    With the upgrade of current gravitational wave detectors, the first detection of gravitational wave signals is expected to occur in the next decade. Low-latency gravitational wave triggers will be necessary to make fast follow-up electromagnetic observations of events related to their source, e.g., prompt optical emission associated with short gamma-ray bursts. In this paper we present a new time-domain low-latency algorithm for identifying the presence of gravitational waves produced by compact binary coalescence events in noisy detector data. Our method calculates the signal to noise ratio from the summation of a bank of parallel infinite impulse response (IIR) filters. We show that our summed parallel infinite impulse response (SPIIR) method can retrieve the signal to noise ratio to greater than 99% of that produced from the optimal matched filter. We emphasise the benefits of the SPIIR method for advanced detectors, which will require larger template banks.

  2. Low-latency analysis pipeline for compact binary coalescences in the advanced gravitational wave detector era

    CERN Document Server

    Adams, T; Germain, V; Guidi, G M; Marion, F; Montani, M; Mours, B; Piergiovanni, F; Wang, G

    2015-01-01

    The Multi-Band Template Analysis (MBTA) pipeline is a low-latency coincident analysis pipeline for the detection of gravitational waves (GWs) from compact binary coalescences (CBCs). MBTA runs with a low computational cost, and can identify candidate GW events online with a sub-minute latency. The low computational running cost of MBTA also makes it useful for data quality studies. Events detected by MBTA online can be used to alert astronomical partners for electromagnetic (EM) follow-up. We outline the current status of MBTA and give details of recent pipeline upgrades and validation tests that were performed in preparation for the first advanced detector observing period. The MBTA pipeline is ready for the outset of the advanced detector era and the exciting prospects it will bring.

  3. A strong law for the rate of growth of long latency periods in cloud computing service

    CERN Document Server

    Ghosh, Souvik

    2010-01-01

    Cloud-computing shares a common pool of resources across customers at a scale that is orders of magnitude larger than traditional multi-user systems. Constituent physical compute servers are allocated multiple "virtual machines" (VM) to serve simultaneously. Each VM user should ideally be unaffected by others' demand. Naturally, this environment produces new challenges for the service providers in meeting customer expectations while extracting an efficient utilization from server resources. We study a new cloud service metric that measures prolonged latency or delay suffered by customers. We model the workload process of a cloud server and analyze the process as the customer population grows. The capacity required to ensure that average workload does not exceed a threshold over long segments is characterized. This can be used by cloud operators to provide service guarantees on avoiding long durations of latency. As part of the analysis, we provide a uniform large-deviation principle for collections of random ...

  4. Intraindividual reaction time variability affects P300 amplitude rather than latency

    Directory of Open Access Journals (Sweden)

    Anusha eRamchurn

    2014-07-01

    Full Text Available The neural correlates of intraindividual response variability were investigated in a serial choice reaction time (CRT task. Reaction times (RTs from the faster and slower portions of the RT distribution for the task were separately aggregated and associated P300 event-related potentials computed. Independent behavioral measures of executive function and IQ were also recorded. Across frontal, fronto-central, central, centro-parietal and parietal scalp regions, P300 amplitudes were significantly greater for faster relative to slower behavioral responses. However, P300 peak amplitude latencies did not differ according to the speed of the behavioral RT. Importantly, controlling for select independent measures of executive function attenuated shared variance in P300 amplitude for faster and slower trials. The findings suggest that P300 amplitude rather than latency is associated with the speed of behavioral RTs, and the possibility that fluctuations in executive control underlie variability in speeded responding.

  5. Capturing the electromagnetic counterparts of binary neutron star mergers through low latency gravitational wave triggers

    CERN Document Server

    Chu, Q; Rowlinson, A; Gao, H; Zhang, B; Tingay, S J; Boer, M; Wen, L

    2015-01-01

    We investigate the prospects for joint low-latency gravitational wave (GW) detection and prompt electromagnetic (EM) follow-up observations of coalescing binary neutron stars (BNSs). Assuming BNS mergers are associated with short duration gamma ray bursts (SGRBs), we evaluate if rapid EM follow-ups can capture the prompt emission, early engine activity or reveal any potential by-products such as magnetars or fast radio bursts. To examine the expected performance of low-latency search pipelines we simulate a population of coalescing BNSs using realistic distributions of source parameters to estimate the detectability and localisation efficiency at different times before merger. To determine what EM observations can be achieved, we consider a selection of facilities with GW follow-up agreements in place, from low-frequency radio to high energy $\\gamma$-ray; we assess the performance of each using observational SGRB flux data corrected to the range of the advanced GW interferometric detectors LIGO and Virgo. We ...

  6. Design and performance of a high resolution, low latency stripline beam position monitor system

    Science.gov (United States)

    Apsimon, R. J.; Bett, D. R.; Blaskovic Kraljevic, N.; Burrows, P. N.; Christian, G. B.; Clarke, C. I.; Constance, B. D.; Dabiri Khah, H.; Davis, M. R.; Perry, C.; Resta López, J.; Swinson, C. J.

    2015-03-01

    A high-resolution, low-latency beam position monitor (BPM) system has been developed for use in particle accelerators and beam lines that operate with trains of particle bunches with bunch separations as low as several tens of nanoseconds, such as future linear electron-positron colliders and free-electron lasers. The system was tested with electron beams in the extraction line of the Accelerator Test Facility at the High Energy Accelerator Research Organization (KEK) in Japan. It consists of three stripline BPMs instrumented with analogue signal-processing electronics and a custom digitizer for logging the data. The design of the analogue processor units is presented in detail, along with measurements of the system performance. The processor latency is 15.6 ±0.1 ns . A single-pass beam position resolution of 291 ±10 nm has been achieved, using a beam with a bunch charge of approximately 1 nC.

  7. [Multiple latency test in a patient with episodes of sleep induced by pergolide].

    Science.gov (United States)

    Jiménez-Jiménez, F J; Velasco, I; de Toledo, M; Sayed, Y; Zurdo, J; Ortí-Pareja, M

    Recently, there have been report sleep attacks in parkinsonian patients as a side effect of pramipexole and ropinirole. We report a patient with similar episodes related with pergolide. A 64 year old man with rigid akinetic parkinsonism, treated with carbidopa/levodopa and pergolide, developed sudden, irresistible sleep episodes after increasing the dose of pergolide to 2.25 mg/day because of bad control of parkinsonian symptoms. These episodes started 30 minutes after each dose of pergolide and lasted 2 hours. Following reduction of the dose of pergolide to 1.5 mg/day the sleep episodes disappeared. Two double blind multiple sleep latency tests were performed, one after intaking pergolide and other after intaking placebo. The latencies to sleep onset were lower with pergolide than with placebo, but the differences did not reach statistical significance. There was no premature REM sleep onset. Sleep episodes are likely a not specific effect of dopamine agonists

  8. Low-latency analysis pipeline for compact binary coalescences in the advanced gravitational wave detector era

    Science.gov (United States)

    Adams, T.; Buskulic, D.; Germain, V.; Guidi, G. M.; Marion, F.; Montani, M.; Mours, B.; Piergiovanni, F.; Wang, G.

    2016-09-01

    The multi-band template analysis (MBTA) pipeline is a low-latency coincident analysis pipeline for the detection of gravitational waves (GWs) from compact binary coalescences. MBTA runs with a low computational cost, and can identify candidate GW events online with a sub-minute latency. The low computational running cost of MBTA also makes it useful for data quality studies. Events detected by MBTA online can be used to alert astronomical partners for electromagnetic follow-up. We outline the current status of MBTA and give details of recent pipeline upgrades and validation tests that were performed in preparation for the first advanced detector observing period. The MBTA pipeline is ready for the outset of the advanced detector era and the exciting prospects it will bring.

  9. A Type of Low-Latency Data Gathering Method with Multi-Sink for Sensor Networks

    Directory of Open Access Journals (Sweden)

    Chao Sha

    2016-06-01

    Full Text Available To balance energy consumption and reduce latency on data transmission in Wireless Sensor Networks (WSNs, a type of low-latency data gathering method with multi-Sink (LDGM for short is proposed in this paper. The network is divided into several virtual regions consisting of three or less data gathering units and the leader of each region is selected according to its residual energy as well as distance to all of the other nodes. Only the leaders in each region need to communicate with the mobile Sinks which have effectively reduced energy consumption and the end-to-end delay. Moreover, with the help of the sleep scheduling and the sensing radius adjustment strategies, redundancy in network coverage could also be effectively reduced. Simulation results show that LDGM is energy efficient in comparison with MST as well as MWST and its time efficiency on data collection is higher than one Sink based data gathering methods.

  10. A comparison of herpes simplex virus type 1 and varicella-zoster virus latency and reactivation

    OpenAIRE

    2015-01-01

    Herpes simplex virus type 1 (HSV-1; human herpesvirus 1) and varicella-zoster virus (VZV; human herpesvirus 3) are human neurotropic alphaherpesviruses that cause lifelong infections in ganglia. Following primary infection and establishment of latency, HSV-1 reactivation typically results in herpes labialis (cold sores), but can occur frequently elsewhere on the body at the site of primary infection (e.g. whitlow), particularly at the genitals. Rarely, HSV-1 reactivation can cause encephaliti...

  11. Synthetic Long Peptide Derived from Mycobacterium tuberculosis Latency Antigen Rv1733c Protects against Tuberculosis.

    Science.gov (United States)

    Coppola, Mariateresa; van den Eeden, Susan J F; Wilson, Louis; Franken, Kees L M C; Ottenhoff, Tom H M; Geluk, Annemieke

    2015-09-01

    Responsible for 9 million new cases of active disease and nearly 2 million deaths each year, tuberculosis (TB) remains a global health threat of overwhelming dimensions. Mycobacterium bovis BCG, the only licensed vaccine available, fails to confer lifelong protection and to prevent reactivation of latent infection. Although 15 new vaccine candidates are now in clinical trials, an effective vaccine against TB remains elusive, and new strategies for vaccination are vital. BCG vaccination fails to induce immunity against Mycobacterium tuberculosis latency antigens. Synthetic long peptides (SLPs) combined with adjuvants have been studied mostly for therapeutic cancer vaccines, yet not for TB, and proved to induce efficient antitumor immunity. This study investigated an SLP derived from Rv1733c, a major M. tuberculosis latency antigen which is highly expressed by "dormant" M. tuberculosis and well recognized by T cells from latently M. tuberculosis-infected individuals. In order to assess its in vivo immunogenicity and protective capacity, Rv1733c SLP in CpG was administered to HLA-DR3 transgenic mice. Immunization with Rv1733c SLP elicited gamma interferon-positive/tumor necrosis factor-positive (IFN-γ(+)/TNF(+)) and IFN-γ(+) CD4(+) T cells and Rv1733c-specific antibodies and led to a significant reduction in the bacterial load in the lungs of M. tuberculosis-challenged mice. This was observed both in a pre- and in a post-M. tuberculosis challenge setting. Moreover, Rv1733c SLP immunization significantly boosted the protective efficacy of BCG, demonstrating the potential of M. tuberculosis latency antigens to improve BCG efficacy. These data suggest a promising role for M. tuberculosis latency antigen Rv1733c-derived SLPs as a novel TB vaccine approach, both in a prophylactic and in a postinfection setting.

  12. Relation between derived-band auditory brainstem response latencies and behavioral frequency selectivity

    DEFF Research Database (Denmark)

    Strelcyk, Olaf; Christoforidis, Dimitrios; Dau, Torsten

    2009-01-01

    Derived-band click-evoked auditory brainstem responses ABRs were obtained for normal-hearing NH and sensorineurally hearing-impaired HI listeners. The latencies extracted from these responses, as a function of derived-band center frequency and click level, served as objective estimates of cochlear...... selectivity in human listeners and offer a window to better understand how hearing impairment affects the spatiotemporal cochlear response pattern....

  13. Note on changes in response latency following discrimination training in the monkey1

    Science.gov (United States)

    Stebbins, William C.; Reynolds, Robert W.

    1964-01-01

    Two monkeys were trained to press and hold down a telegraph key in the presence of a red light. Subsequent release of the key in response to a white cross superimposed on the red background was followed by reinforcement. Key release in response to a white circle on the red background was never reinforced. Latencies for the key release response to the reinforced stimulus (cross) were considerably shorter and less variable than those to the unreinforced stimulus (circle). PMID:14143909

  14. Bryostatin-1 synergizes with histone deacetylase inhibitors to reactivate HIV-1 from latency.

    Science.gov (United States)

    Pérez, Moisés; de Vinuesa, Amaya García; Sanchez-Duffhues, Gonzalo; Marquez, Nieves; Bellido, M Luz; Muñoz-Fernandez, M Angeles; Moreno, Santiago; Castor, Trevor P; Calzado, Marco A; Muñoz, Eduardo

    2010-09-01

    The persistence of latent HIV-infected cellular reservoirs represents the major hurdle to virus eradication on patients treated with HAART. It has been suggested that successful depletion of such latent reservoirs will require a combination of therapeutic agents that can specifically and efficiently act on cells harboring latent HIV-1 provirus. Using Jurkat-LAT-GFP cells, a tractable model of HIV-1 latency, we have found that bryostatin -1 reactivates HIV-1 through a classical PKC-dependent pathway. Bryostatin-1 also activates MAPKs and NF-κB pathways and synergizes with HDAC inhibitors to reactivate HIV-1 from latency. Bryostatin-1 downregulates the expression of the HIV-1 co-receptors CD4 and CXCR4 and prevented de novo HIV-1 infection in susceptible cells. We applied proteomic methods to investigate major changes in protein expression in Jurkat-LAT-GFP under latency and reactivation conditions. We identified up-regulation of proteins that may be involved in the innate anti-HIV-1 response (NKEF-A and MHD2) and in different cell functions (i.e. cofilin-1 and transgelin-2) of the host cells. PKC agonists may represent a valuable pharmacological approach to purge latent HIV from cellular reservoirs and at the moment, the only clinically available PKC agonist is bryostatin-1. This drug has been tested in numerous clinical trials and its pharmacokinetics and toxicity in humans is well known. Moreover, bryostatin-1 potently synergizes with other HDAC inhibitors commonly used in the medical practice such as valproic acid. Therefore, bryostatin-1, alone or in combination with HDAC inhibitors, could be used in HAART treated patients to validate the hypothesis that reactivating HIV-1 from latency could purge HIV-1 reservoirs.

  15. Area/latency optimized early output asynchronous full adders and relative-timed ripple carry adders.

    Science.gov (United States)

    Balasubramanian, P; Yamashita, S

    2016-01-01

    This article presents two area/latency optimized gate level asynchronous full adder designs which correspond to early output logic. The proposed full adders are constructed using the delay-insensitive dual-rail code and adhere to the four-phase return-to-zero handshaking. For an asynchronous ripple carry adder (RCA) constructed using the proposed early output full adders, the relative-timing assumption becomes necessary and the inherent advantages of the relative-timed RCA are: (1) computation with valid inputs, i.e., forward latency is data-dependent, and (2) computation with spacer inputs involves a bare minimum constant reverse latency of just one full adder delay, thus resulting in the optimal cycle time. With respect to different 32-bit RCA implementations, and in comparison with the optimized strong-indication, weak-indication, and early output full adder designs, one of the proposed early output full adders achieves respective reductions in latency by 67.8, 12.3 and 6.1 %, while the other proposed early output full adder achieves corresponding reductions in area by 32.6, 24.6 and 6.9 %, with practically no power penalty. Further, the proposed early output full adders based asynchronous RCAs enable minimum reductions in cycle time by 83.4, 15, and 8.8 % when considering carry-propagation over the entire RCA width of 32-bits, and maximum reductions in cycle time by 97.5, 27.4, and 22.4 % for the consideration of a typical carry chain length of 4 full adder stages, when compared to the least of the cycle time estimates of various strong-indication, weak-indication, and early output asynchronous RCAs of similar size. All the asynchronous full adders and RCAs were realized using standard cells in a semi-custom design fashion based on a 32/28 nm CMOS process technology.

  16. Does behavioral response to novelty influence paw withdrawal latencies in repeated Hargreaves test?

    OpenAIRE

    Tvrdeić, Ante; Kočevski, Dragana

    2008-01-01

    Background and Purpose: Only recently, we have reported that single retesting session significantly decreases rat paw withdrawal latencies (PWL) in Hargreaves tests.We wondered, whether decrease in PWL values obtained during reexposure toHargreaves testmight be associated with reaction to the new environment. Therefore, we investigated PWL together with the open field behavior in an enclosure of the Hargreaves test device during the period of 3 subsequent days. Materials and Methods: Ten...

  17. Is the long-latency stretch reflex in human masseter transcortical?

    Science.gov (United States)

    Pearce, Sophie L; Miles, Timothy S; Thompson, Philip D; Nordstrom, Michael A

    2003-06-01

    A long-latency stretch reflex (LLSR) has been described in the human masseter muscle, but its pathway remains uncertain. To investigate this, the excitability of corticomotoneuronal (CM) cells projecting to masseter motoneurons during the LLSR was assessed with transcranial magnetic stimulation (TMS). A facilitated response to TMS would be evidence of a LLSR pathway that traverses the motor cortex. Surface electromyogram electrodes were placed over the left or right masseter, and subjects ( n=10) bit on bars with their incisor teeth at 10% of maximal electromyographic activity (EMG). Servo-controlled displacements were imposed on the lower jaw to evoke a short- and long-latency stretch reflex in masseter. TMS intensity was just suprathreshold for a response in contralateral masseter. Trials consisted of: (1) stretch alone, (2) TMS alone, and (3) TMS with a preceding conditioning stretch at varied conditioning-testing (C-T) intervals chosen to combine TMS with the short-latency stretch reflex (3 ms, 5 ms) and the LLSR (23-41 ms). Masseter EMG was rectified and averaged. With TMS alone, mean (+/- SE) MEP area above baseline was 56+/-9%. The area of masseter MEPs above baseline in the C-T trials was calculated from each EMG average following subtraction of the response to stretch alone. Conditioning muscle stretch had no significant effect on masseter MEPs evoked by TMS with any C-T interval (ANOVA; P=0.90). In addition, subjects were unable to modify the SLSR or LLSR by voluntary command. It is concluded that the long-latency stretch reflex in the masseter does not involve the motor cortex and is not influenced by "motor set".

  18. Pemodelan dan Verifikasi Formal Pengaruh Mobility pattern Terhadap Handoff Latency pada Jaringan WiMAX

    Directory of Open Access Journals (Sweden)

    I Nym Saputra Wahyu Wijaya

    2016-01-01

    Full Text Available In order to decrease handoff latency and increase the successful of HHO conventional scheme, a development of handover scheme is done in standard protocol WiMAX IEEE 802.16e by adding mobility pattern. The superiority of handover scheme with mobility pattern can reduce handoff latency up to 50%, mean while the weakness of this scheme is a wrong act in determining target base station are often happen. Simulation can not showing the cause of that error. So, we do formal verification in to hard handover model with mobility pattern.             In this research, behaviour system is modeled with continuous-time Markov chain (CTMC. The model is foccused to aproximating the influence of mobility pattern in to handoff latency from WiMAX hard handover mechanism. In order to set up a series markov chain models handover system can follow steps, such as: represents the state space, give a number in all transitions, generate the rate transition matrix (infinitesimal generator.             Probabilistic model checking in the research are using quantitative properties and qualitative properties. Formal verification concerning properties has relation with handover in WiMAX network showing that 70% from mobile station which doing scanning with mobility pattern are success doing handover. 24% of them doing scanning conventional as a result of wrongness in act determining target base station, so handoff latency which is pictured will bigger than a system that is only use conventional scanning method.

  19. Latency-Efficient Communication in Wireless Mesh Networks under Consideration of Large Interference Range

    Science.gov (United States)

    Xin, Qin; Yao, Xiaolan; Engelstad, Paal E.

    2010-09-01

    Wireless Mesh Networking is an emerging communication paradigm to enable resilient, cost-efficient and reliable services for the future-generation wireless networks. We study here the minimum-latency communication primitive of gossiping (all-to-all communication) in multi-hop ad-hoc Wireless Mesh Networks (WMNs). Each mesh node in the WMN is initially given a message and the objective is to design a minimum-latency schedule such that each mesh node distributes its message to all other mesh nodes. Minimum-latency gossiping problem is well known to be NP-hard even for the scenario in which the topology of the WMN is known to all mesh nodes in advance. In this paper, we propose a new latency-efficient approximation scheme that can accomplish gossiping task in polynomial time units in any ad-hoc WMN under consideration of Large Interference Range (LIR), e.g., the interference range is much larger than the transmission range. To the best of our knowledge, it is first time to investigate such a scenario in ad-hoc WMNs under LIR, our algorithm allows the labels (e.g., identifiers) of the mesh nodes to be polynomially large in terms of the size of the WMN, which is the first time that the scenario of large labels has been considered in ad-hoc WMNs under LIR. Furthermore, our gossiping scheme can be considered as a framework which can be easily implied to the scenario under consideration of mobility-related issues since we assume that the mesh nodes have no knowledge on the network topology even for its neighboring mesh nodes.

  20. Design and performance of a high resolution, low latency stripline beam position monitor system

    OpenAIRE

    R. J. Apsimon; D. R. Bett; N. Blaskovic Kraljevic; P. N. Burrows; G. B. Christian; C. I. Clarke; B. D. Constance; Dabiri Khah, H.; M. R. Davis; Perry, C; J. Resta López; C. J. Swinson

    2015-01-01

    A high-resolution, low-latency beam position monitor (BPM) system has been developed for use in particle accelerators and beam lines that operate with trains of particle bunches with bunch separations as low as several tens of nanoseconds, such as future linear electron-positron colliders and free-electron lasers. The system was tested with electron beams in the extraction line of the Accelerator Test Facility at the High Energy Accelerator Research Organization (KEK) in Japan. It consists of...

  1. Analysis of variance of communication latencies in anesthesia: comparing means of multiple log-normal distributions.

    Science.gov (United States)

    Ledolter, Johannes; Dexter, Franklin; Epstein, Richard H

    2011-10-01

    Anesthesiologists rely on communication over periods of minutes. The analysis of latencies between when messages are sent and responses obtained is an essential component of practical and regulatory assessment of clinical and managerial decision-support systems. Latency data including times for anesthesia providers to respond to messages have moderate (> n = 20) sample sizes, large coefficients of variation (e.g., 0.60 to 2.50), and heterogeneous coefficients of variation among groups. Highly inaccurate results are obtained both by performing analysis of variance (ANOVA) in the time scale or by performing it in the log scale and then taking the exponential of the result. To overcome these difficulties, one can perform calculation of P values and confidence intervals for mean latencies based on log-normal distributions using generalized pivotal methods. In addition, fixed-effects 2-way ANOVAs can be extended to the comparison of means of log-normal distributions. Pivotal inference does not assume that the coefficients of variation of the studied log-normal distributions are the same, and can be used to assess the proportional effects of 2 factors and their interaction. Latency data can also include a human behavioral component (e.g., complete other activity first), resulting in a bimodal distribution in the log-domain (i.e., a mixture of distributions). An ANOVA can be performed on a homogeneous segment of the data, followed by a single group analysis applied to all or portions of the data using a robust method, insensitive to the probability distribution.

  2. X-ray Studies of Flaring Plasma

    Indian Academy of Sciences (India)

    B. Sylwester; J. Sylwester; K. J. H. Phillips

    2008-03-01

    We present some methods of X-ray data analysis employed in our laboratory for deducing the physical parameters of flaring plasma. For example, we have used a flare well observed with Polish instrument RESIK aboard Russian CORONAS-F satellite. Based on a careful instrument calibration, the absolute fluxes in a number of individual spectral lines have been obtained. The analysis of these lines allows us to follow the evolution of important thermodynamic parameters characterizing the emitting plasma throughout this flare evolution.

  3. Mismatch field latency, but not power, may mark a shared autistic and schizotypal trait phenotype.

    Science.gov (United States)

    Ford, Talitha C; Woods, Will; Crewther, David P

    2017-02-21

    The auditory mismatch negativity (MMN), a preattentive processing potential, and its magnetic counterpart (MMF) are consistently reported as reduced in schizophrenia and autism spectrum disorders. This study investigates whether MMF characteristics differ between subclinically high and low scorers on the recently discovered shared autism and schizophrenia phenotype, Social Disorganisation. A total of 18 low (10 females) and 19 high (9 females) Social Disorganisation scorers underwent magnetoencephalography (MEG) during a MMF paradigm of 50ms standard (1000Hz, 85%) and 100ms duration deviant tones. MMF was measured from the strongest active magnetometer over the right and left hemispheres (consistent across groups) after 100ms. No differences in MMF power were found, however there was a significant delay in the MMF peak (p=0.007). The P3am (following the MMF) was significantly reduced across both hemispheres for the high Social Disorganisation group (p=0.025), there were no specific hemispheric differences in P3am power or latency. Right MMF peak latency increased with higher scores on the schizotypal subscales Odd Speech, Odd Behaviour and Constricted Affect. Findings suggest that MMF peak latency delay marks a convergence of the autism and schizophrenia spectra at a subclinical. These findings have significant implications for future research methodology, as well as clinical practice.

  4. The Relationship between Parameters of Long-Latency Evoked Potentials in a Multisensory Design.

    Science.gov (United States)

    Hernández, Oscar H; García-Martínez, Rolando; Monteón, Victor

    2016-10-01

    In previous papers, we have shown that parameters of the omitted stimulus potential (OSP), which occurs at the end of a train of sensory stimuli, strongly depend on the modality. A train of stimuli also produces long-latency evoked potentials (LLEP) at the beginning of the train. This study is an extension of the OSP research, and it tested the relationship between parameters (ie, rate of rise, amplitude, and peak latency) of the P2 waves when trains of auditory, visual, or somatosensory stimuli were applied. The dynamics of the first 3 potentials in the train, related to habituation, were also studied. Twenty healthy young college volunteers participated in the study. As in the OSP, the P2 was faster and higher for auditory than for visual or somatosensory stimuli. The first P2 was swifter and higher than the second and the third potentials. The strength of habituation depends on the sensory modality and the parameter used. All these findings support the view that many long-latency brain potentials could share neural mechanisms related to wave generation.

  5. Human Space Exploration and Human Space Flight: Latency and the Cognitive Scale of the Universe

    Science.gov (United States)

    Lester, Dan; Thronson, Harley

    2011-01-01

    The role of telerobotics in space exploration as placing human cognition on other worlds is limited almost entirely by the speed of light, and the consequent communications latency that results from large distances. This latency is the time delay between the human brain at one end, and the telerobotic effector and sensor at the other end. While telerobotics and virtual presence is a technology that is rapidly becoming more sophisticated, with strong commercial interest on the Earth, this time delay, along with the neurological timescale of a human being, quantitatively defines the cognitive horizon for any locale in space. That is, how distant can an operator be from a robot and not be significantly impacted by latency? We explore that cognitive timescale of the universe, and consider the implications for telerobotics, human space flight, and participation by larger numbers of people in space exploration. We conclude that, with advanced telepresence, sophisticated robots could be operated with high cognition throughout a lunar hemisphere by astronauts within a station at an Earth-Moon Ll or L2 venue. Likewise, complex telerobotic servicing of satellites in geosynchronous orbit can be carried out from suitable terrestrial stations.

  6. Latencies in action potential stimulation in a two-dimensional bidomain: A numerical simulation

    Science.gov (United States)

    Barach, John Paul

    1991-05-01

    A numerical simulation is performed in which a uniform planar slab of idealized cardiac tissue is stimulated at the center. The cardiac slab is modeled as an anisotropic bidomain; within each domain current flow is determined by a forced diffusion equation in which the transmembrane current connecting the domains provides the forcing term. An action potential (AP) propagates outward after a time latency dependent upon the stimulus size and the physiological variables. Its isochrones are elliptical with an asymmetry that is a small fraction of the imposed asymmetry in resistivity. External voltages resemble the first derivative of those in the internal domain and tests with continuing stimuli exhibit a relaxation time of about 3 ms and space constants that agree with other work. The AP latency increases very strongly near threshold stimulus and decreases as the log (stimulus) for large stimuli in the ``virtual cathode'' range. Latencies in the longitudinal, transverse, and diagonal directions are found to be the same over a wide range of stimulus size and type.

  7. Long latency trigemino-cervical reflex in patients with cervical dystonia.

    Science.gov (United States)

    Gündüz, Ayşegül; Ergin, Hayal; Kızıltan, Meral E

    2015-01-01

    Trigemino-cervical reflex (TCR) is elicited by stimulation of face using various modalities. TCR reflects the interaction between trigeminal system and cervical motoneurons. Such a specific interaction is assumed to play role in development of cervical dystonia (CD) through superior colliculus. In this study, we aimed to investigate alterations of the functional relationship between those structures in CD and in a subgroup with dystonic tremor. A total of consecutive 23 patients with primary CD (7 men, 16 women) and 16 age and sex matched control subjects (7 men, 9 women) were included in this study. TCR was obtained after percutaneous electrical stimulation (with duration of 0.5 ms) of infraorbital branch of trigeminal nerve while recording over splenius capitis and sternocleidomastoid muscles. Presence and onset latencies of TCR did not differ significantly between patients with CD and controls, and same pattern of muscle activation occurred in both groups. Responses of patient group seemed to have higher amplitudes and to be more persistent. There were no significant side-to-side differences of TCR probability, latency, amplitude or duration with respect to the side of head deviation in CD. Increased amplitudes and durations of responses probably reflect increased excitability of the reflex circuit. We suggest that similar latencies and response pattern in comparison to healthy individuals decrease the possibility of structural disturbance. TCR is probably under bilateral basal ganglia and dopaminergic control. Alterations of trigemino-cervical pathway are more extensive and are not solely due to local changes of brainstem interneurons.

  8. Short-latency tachycardia evoked by stimulation of muscle and cutaneous afferents.

    Science.gov (United States)

    Gelsema, A J; Bouman, L N; Karemaker, J M

    1985-04-01

    The short-latency effect on heart rate of peripheral nerve stimulation was studied in decerebrate cats. Selective activation (17-40 microA, 100 Hz, 1 s long) of low-threshold fibers in the nerves to the triceps surae muscle yielded isometric contractions of maximal force that were accompanied by a cardiac cycle length shortening within 0.4 s from the start of stimulation. This effect was abolished by pharmacologically induced neuromuscular blockade. The cardiac cycle length shortening during paralysis reappeared after a 6- to 10-fold increase of the stimulation strength. Cutaneous (sural) nerve stimulation (15-25 microA, 100 Hz, 1 s long) elicited reflex contractions in the stimulated limb, which were also accompanied by a cardiac acceleration with similar latency. Paralysis prevented the reflex contractions and reduced the cardiac response in some cats and abolished it in others. The response reappeared in either case after a 5- to 10-fold increase of the stimulus strength. It is concluded that muscle nerve and cutaneous nerve activity both cause a similar cardiac acceleration with a latency of less than 0.4 s. The response to muscle nerve stimulation is elicited by activity in group III afferents. It is excluded that the cardiac response to nerve stimulation is secondary to a change in the respiratory pattern.

  9. Targeted HIV-1 Latency Reversal Using CRISPR/Cas9-Derived Transcriptional Activator Systems.

    Directory of Open Access Journals (Sweden)

    Julia K Bialek

    Full Text Available CRISPR/Cas9 technology is currently considered the most advanced tool for targeted genome engineering. Its sequence-dependent specificity has been explored for locus-directed transcriptional modulation. Such modulation, in particular transcriptional activation, has been proposed as key approach to overcome silencing of dormant HIV provirus in latently infected cellular reservoirs. Currently available agents for provirus activation, so-called latency reversing agents (LRAs, act indirectly through cellular pathways to induce viral transcription. However, their clinical performance remains suboptimal, possibly because reservoirs have diverse cellular identities and/or proviral DNA is intractable to the induced pathways. We have explored two CRISPR/Cas9-derived activator systems as targeted approaches to induce dormant HIV-1 proviral DNA. These systems recruit multiple transcriptional activation domains to the HIV 5' long terminal repeat (LTR, for which we have identified an optimal target region within the LTR U3 sequence. Using this target region, we demonstrate transcriptional activation of proviral genomes via the synergistic activation mediator complex in various in culture model systems for HIV latency. Observed levels of induction are comparable or indeed higher than treatment with established LRAs. Importantly, activation is complete, leading to production of infective viral particles. Our data demonstrate that CRISPR/Cas9-derived technologies can be applied to counteract HIV latency and may therefore represent promising novel approaches in the quest for HIV elimination.

  10. Experiences from Implementing a Mobile Multiplayer Real-Time Game for Wireless Networks with High Latency

    Directory of Open Access Journals (Sweden)

    Alf Inge Wang

    2009-01-01

    Full Text Available This paper describes results and experiences from designing, implementing, and testing a multiplayer real-time game over mobile networks with high latency. The paper reports on network latency and bandwidth measurements from playing the game live over GPRS, EDGE, UMTS, and WLAN using the TCP and the UDP protocols. These measurements describe the practical constraints of various wireless networks and protocols when used for mobile multiplayer game purposes. Further, the paper reports on experiences from implementing various approaches to minimize issues related to high latency. Specifically, the paper focuses on a discussion about how much of the game should run locally on the client versus on the server to minimize the load on the mobile device and obtain sufficient consistency in the game. The game was designed to reveal all kinds of implementation issues of mobile network multiplayer games. The goal of the game is for a player to push other players around and into traps where they loose their lives. The game relies heavily on collision detection between the players and game objects. The paper presents experiences from experimenting with various approaches that can be used to handle such collisions, and highlights the advantages and disadvantages of the various approaches.

  11. Redundant Logic Insertion and Latency Reduction in Self-Timed Adders

    Directory of Open Access Journals (Sweden)

    P. Balasubramanian

    2012-01-01

    Full Text Available A novel concept of logic redundancy insertion is presented that facilitates significant latency reduction in self-timed adder circuits. The proposed concept is universal in the sense that it can be extended to a variety of self-timed design methods. Redundant logic can be incorporated to generate efficient self-timed realizations of iterative logic specifications. Based on the case study of a 32-bit self-timed carry-ripple adder, it has been found that redundant implementations minimize the data path latency by 21.1% at the expense of increases in area and power by 2.3% and 0.8% on average compared to their nonredundant counterparts. However, when considering further peephole logic optimizations, it has been observed in a specific scenario that the delay reduction could be as high as 31% while accompanied by only meager area and power penalties of 0.6% and 1.2%, respectively. Moreover, redundant logic adders pave the way for spacer propagation in constant time and garner actual case latency for addition of valid data.

  12. Energy-Latency Tradeoff for In-Network Function Computation in Random Networks

    CERN Document Server

    Balister, Paul; Anandkumar, Animashree; Willsky, Alan

    2011-01-01

    The problem of designing policies for in-network function computation with minimum energy consumption subject to a latency constraint is considered. The scaling behavior of the energy consumption under the latency constraint is analyzed for random networks, where the nodes are uniformly placed in growing regions and the number of nodes goes to infinity. The special case of sum function computation and its delivery to a designated root node is considered first. A policy which achieves order-optimal average energy consumption in random networks subject to the given latency constraint is proposed. The scaling behavior of the optimal energy consumption depends on the path-loss exponent of wireless transmissions and the dimension of the Euclidean region where the nodes are placed. The policy is then extended to computation of a general class of functions which decompose according to maximal cliques of a proximity graph such as the $k$-nearest neighbor graph or the geometric random graph. The modified policy achiev...

  13. Latency requirements for head-worn display S/EVS applications

    Science.gov (United States)

    Bailey, Randall E.; Arthur, Jarvis J., III; Williams, Steven P.

    2004-08-01

    NASA's Aviation Safety Program, Synthetic Vision Systems Project is conducting research in advanced flight deck concepts, such as Synthetic/Enhanced Vision Systems (S/EVS), for commercial and business aircraft. An emerging thrust in this activity is the development of spatially-integrated, large field-of-regard information display systems. Head-worn or helmet-mounted display systems are being proposed as one method in which to meet this objective. System delays or latencies inherent to spatially-integrated, head-worn displays critically influence the display utility, usability, and acceptability. Research results from three different, yet similar technical areas - flight control, flight simulation, and virtual reality - are collectively assembled in this paper to create a global perspective of delay or latency effects in head-worn or helmet-mounted display systems. Consistent definitions and measurement techniques are proposed herein for universal application and latency requirements for Head-Worn Display S/EVS applications are drafted. Future research areas are defined.

  14. Thermal and Cure Kinetics of Epoxy Molding Compounds Cured with Thermal Latency Accelerators

    Directory of Open Access Journals (Sweden)

    Chean-Cheng Su

    2013-01-01

    Full Text Available The cure kinetics and mechanisms of a biphenyl type epoxy molding compounds (EMCs with thermal latency organophosphine accelerators were studied using differential scanning calorimetry (DSC. Although the use of triphenylphosphine-1,4-benzoquinone (TPP-BQ and triphenylphosphine (TPP catalysts in biphenyl type EMCs exhibited autocatalytic mechanisms, thermal latency was higher in the TPP-BQ catalyst in EMCs than in the TPP catalyst in EMCs. Analyses of thermal characteristics indicated that TPP-BQ is inactive at low temperatures. At high temperatures, however, TPP-BQ increases the curing rate of EMC in dynamic and isothermal curing experiments. The reaction of EMCs with the TPP-BQ latent catalyst also had a higher temperature sensitivity compared to the reaction of EMCs with TPP catalyst. In resin transfer molding, EMCs containing the TPP-BQ thermal latency accelerator are least active at a low temperature. Consequently, EMCs have a low melt viscosity before gelation, and the resins and filler are evenly mixed in the kneading process. Additionally, flowability is increased before the EMCs form a network structure in the molding process. The proposed kinetic model adequately describes curing behavior in EMCs cured with two different organophosphine catalysts up to the rubber state in the progress of curing.

  15. Zebra Alphaherpesviruses (EHV-1 and EHV-9: Genetic Diversity, Latency and Co-Infections

    Directory of Open Access Journals (Sweden)

    Azza Abdelgawad

    2016-09-01

    Full Text Available Alphaherpesviruses are highly prevalent in equine populations and co-infections with more than one of these viruses’ strains frequently diagnosed. Lytic replication and latency with subsequent reactivation, along with new episodes of disease, can be influenced by genetic diversity generated by spontaneous mutation and recombination. Latency enhances virus survival by providing an epidemiological strategy for long-term maintenance of divergent strains in animal populations. The alphaherpesviruses equine herpesvirus 1 (EHV-1 and 9 (EHV-9 have recently been shown to cross species barriers, including a recombinant EHV-1 observed in fatal infections of a polar bear and Asian rhinoceros. Little is known about the latency and genetic diversity of EHV-1 and EHV-9, especially among zoo and wild equids. Here, we report evidence of limited genetic diversity in EHV-9 in zebras, whereas there is substantial genetic variability in EHV-1. We demonstrate that zebras can be lytically and latently infected with both viruses concurrently. Such a co-occurrence of infection in zebras suggests that even relatively slow-evolving viruses such as equine herpesviruses have the potential to diversify rapidly by recombination. This has potential consequences for the diagnosis of these viruses and their management in wild and captive equid populations.

  16. Global mRNA degradation during lytic gammaherpesvirus infection contributes to establishment of viral latency.

    Directory of Open Access Journals (Sweden)

    Justin M Richner

    2011-07-01

    Full Text Available During a lytic gammaherpesvirus infection, host gene expression is severely restricted by the global degradation and altered 3' end processing of mRNA. This host shutoff phenotype is orchestrated by the viral SOX protein, yet its functional significance to the viral lifecycle has not been elucidated, in part due to the multifunctional nature of SOX. Using an unbiased mutagenesis screen of the murine gammaherpesvirus 68 (MHV68 SOX homolog, we isolated a single amino acid point mutant that is selectively defective in host shutoff activity. Incorporation of this mutation into MHV68 yielded a virus with significantly reduced capacity for mRNA turnover. Unexpectedly, the MHV68 mutant showed little defect during the acute replication phase in the mouse lung. Instead, the virus exhibited attenuation at later stages of in vivo infections suggestive of defects in both trafficking and latency establishment. Specifically, mice intranasally infected with the host shutoff mutant accumulated to lower levels at 10 days post infection in the lymph nodes, failed to develop splenomegaly, and exhibited reduced viral DNA levels and a lower frequency of latently infected splenocytes. Decreased latency establishment was also observed upon infection via the intraperitoneal route. These results highlight for the first time the importance of global mRNA degradation during a gammaherpesvirus infection and link an exclusively lytic phenomenon with downstream latency establishment.

  17. HIVed, a knowledgebase for differentially expressed human genes and proteins during HIV infection, replication and latency

    Science.gov (United States)

    Li, Chen; Ramarathinam, Sri H.; Revote, Jerico; Khoury, Georges; Song, Jiangning; Purcell, Anthony W.

    2017-01-01

    Measuring the altered gene expression level and identifying differentially expressed genes/proteins during HIV infection, replication and latency is fundamental for broadening our understanding of the mechanisms of HIV infection and T-cell dysfunction. Such studies are crucial for developing effective strategies for virus eradication from the body. Inspired by the availability and enrichment of gene expression data during HIV infection, replication and latency, in this study, we proposed a novel compendium termed HIVed (HIV expression database; http://hivlatency.erc.monash.edu/) that harbours comprehensive functional annotations of proteins, whose genes have been shown to be dysregulated during HIV infection, replication and latency using different experimental designs and measurements. We manually curated a variety of third-party databases for structural and functional annotations of the protein entries in HIVed. With the goal of benefiting HIV related research, we collected a number of biological annotations for all the entries in HIVed besides their expression profile, including basic protein information, Gene Ontology terms, secondary structure, HIV-1 interaction and pathway information. We hope this comprehensive protein-centric knowledgebase can bridge the gap between the understanding of differentially expressed genes and the functions of their protein products, facilitating the generation of novel hypotheses and treatment strategies to fight against the HIV pandemic. PMID:28358052

  18. Measurement-based analysis of error latency. [in computer operating system

    Science.gov (United States)

    Chillarege, Ram; Iyer, Ravishankar K.

    1987-01-01

    This paper demonstrates a practical methodology for the study of error latency under a real workload. The method is illustrated with sampled data on the physical memory activity, gathered by hardware instrumentation on a VAX 11/780 during the normal workload cycle of the installation. These data are used to simulate fault occurrence and to reconstruct the error discovery process in the system. The technique provides a means to study the system under different workloads and for multiple days. An approach to determine the percentage of undiscovered errors is also developed and a verification of the entire methodology is performed. This study finds that the mean error latency, in the memory containing the operating system, varies by a factor of 10 to 1 (in hours) between the low and high workloads. It is found that of all errors occurring within a day, 70 percent are detected in the same day, 82 percent within the following day, and 91 percent within the third day. The increase in failure rate due to latency is not so much a function of remaining errors but is dependent on whether or not there is a latent error.

  19. The Role of Sports in the Development of the Superego of the Male Latency Child.

    Science.gov (United States)

    Shopper, Moisy

    2014-01-01

    Psychoanalytic literature has often overlooked the child's participation in organized sports, which often can facilitate or impede not only expression of aggression and narcissism, but enhance or skew the growth of the child's superego and ego ideal. Specific outcomes are largely determined by the experience and knowledge of the parents, the coaches, and sports organizations for latency-aged youth. Sports participation facilitates a major step forward in psychic development, that is, an agreed-upon adherence to a set of rules and regulations, monitored by an official embodying the final word regarding rules and their infractions. This paper is an attempt to delineate the role of sports in the life of the latency child, the parents who become involved, the coaches who teach and supervise, and the social and individual milieu within which sports take place. All these contribute to common goals: the engendering of good sportsmanship and the encouragement of psychic growth, particularly regarding how aggression and narcissism contribute to the development of superego and ego ideals. The fate of aggression and narcissism in superego and ego ideal development is influenced to a large degree by the nature, orientation, and motivations of all involved in sports for the latency-aged.

  20. Mapping and correction of vascular hemodynamic latency in the BOLD signal.

    Science.gov (United States)

    Chang, Catie; Thomason, Moriah E; Glover, Gary H

    2008-10-15

    Correlation and causality metrics can be applied to blood-oxygen level-dependent (BOLD) signal time series in order to infer neural synchrony and directions of information flow from fMRI data. However, the BOLD signal reflects both the underlying neural activity and the vascular response, the latter of which is governed by local vasomotor physiology. The presence of potential vascular latency differences thus poses a confound in the detection of neural synchrony as well as inferences about the causality of neural processes. In the present study, we investigate the use of a breath holding (BH) task for characterizing and correcting for voxel-wise neurovascular latency differences across the whole brain. We demonstrate that BH yields reliable measurements of relative timing differences between voxels, and further show that a BH-derived latency correction can impact both functional connectivity maps of the resting-state default-mode network and activation maps of an event-related working memory (WM) task.

  1. Use of a latency-based demand assessment to identify potential demands for functional analyses.

    Science.gov (United States)

    Call, Nathan A; Miller, Sarah J; Mintz, Joslyn Cynkus; Mevers, Joanna Lomas; Scheithauer, Mindy C; Eshelman, Julie E; Beavers, Gracie A

    2016-12-01

    Unlike potential tangible positive reinforcers, which are typically identified for inclusion in functional analyses empirically using preference assessments, demands are most often selected arbitrarily or based on caregiver report. The present study evaluated the use of a demand assessment with 12 participants who exhibited escape-maintained problem behavior. Participants were exposed to 10 demands, with aversiveness measured by average latency to the first instance of problem behavior. In subsequent functional analyses, results of a demand condition that included the demand with the shortest latency to problem behavior resulted in identification of an escape function for 11 of the participants. In contrast, a demand condition that included the demand with the longest latency resulted in identification of an escape function for only 5 participants. The implication of these findings is that for the remaining 7 participants, selection of the demand for the functional analysis without using the results of the demand assessment could have produced a false-negative finding. © 2016 Society for the Experimental Analysis of Behavior.

  2. Low-Latency Teleoperations for Human Exploration and Evolvable Mars Campaign

    Science.gov (United States)

    Lupisella, Mark; Wright, Michael; Arney, Dale; Gershman, Bob; Stillwagen, Fred; Bobskill, Marianne; Johnson, James; Shyface, Hilary; Larman, Kevin; Lewis, Ruthan; Bleacher, Jake; Gernhardt, Mike; Mueller, Rob; Sanders, Gerald; Watts, Kevin; Eigenbrode, Jen; Garry, Brent; Freeh, Joshua; Manzella, David; Hack, Kurt; Aranyos, Tom

    2015-01-01

    NASA has been analyzing a number of mission concepts and activities that involve low-latency telerobotic (LLT) operations. One mission concept that will be covered in this presentation is Crew-Assisted Sample Return which involves the crew acquiring samples (1) that have already been delivered to space, and or acquiring samples via LLT from orbit to a planetary surface and then launching the samples to space to be captured in space and then returned to the earth with the crew. Both versions of have key roles for low-latency teleoperations. More broadly, the NASA Evolvable Mars Campaign is exploring a number of other activities that involve LLT, such as: (a) human asteroid missions, (b) PhobosDeimos missions, (c) Mars human landing site reconnaissance and site preparation, and (d) Mars sample handling and analysis. Many of these activities could be conducted from Mars orbit and also with the crew on the Mars surface remotely operating assets elsewhere on the surface, e.g. for exploring Mars special regions and or teleoperating a sample analysis laboratory both of which may help address planetary protection concerns. The operational and technology implications of low-latency teleoperations will be explored, including discussion of relevant items in the NASA Technology Roadmap and also how previously deployed robotic assets from any source could subsequently be used by astronauts via LLT.

  3. First low-latency LIGO+Virgo search for binary inspirals and their electromagnetic counterparts

    Science.gov (United States)

    Abadie, J.; Abbott, B. P.; Abbott, R.; Abbott, T. D.; Abernathy, M.; Accadia, T.; Acernese, F.; Adams, C.; Adhikari, R.; Affeldt, C.; Agathos, M.; Agatsuma, K.; Ajith, P.; Allen, B.; Amador Ceron, E.; Amariutei, D.; Anderson, S. B.; Anderson, W. G.; Arai, K.; Arain, M. A.; Araya, M. C.; Aston, S. M.; Astone, P.; Atkinson, D.; Aufmuth, P.; Aulbert, C.; Aylott, B. E.; Babak, S.; Baker, P.; Ballardin, G.; Ballmer, S.; Barayoga, J. C. B.; Barker, D.; Barone, F.; Barr, B.; Barsotti, L.; Barsuglia, M.; Barton, M. A.; Bartos, I.; Bassiri, R.; Bastarrika, M.; Basti, A.; Batch, J.; Bauchrowitz, J.; Bauer, Th. S.; Bebronne, M.; Beck, D.; Behnke, B.; Bejger, M.; Beker, M. G.; Bell, A. S.; Belletoile, A.; Belopolski, I.; Benacquista, M.; Berliner, J. M.; Bertolini, A.; Betzwieser, J.; Beveridge, N.; Beyersdorf, P. T.; Bilenko, I. A.; Billingsley, G.; Birch, J.; Biswas, R.; Bitossi, M.; Bizouard, M. A.; Black, E.; Blackburn, J. K.; Blackburn, L.; Blair, D.; Bland, B.; Blom, M.; Bock, O.; Bodiya, T. P.; Bogan, C.; Bondarescu, R.; Bondu, F.; Bonelli, L.; Bonnand, R.; Bork, R.; Born, M.; Boschi, V.; Bose, S.; Bosi, L.; Bouhou, B.; Braccini, S.; Bradaschia, C.; Brady, P. R.; Braginsky, V. B.; Branchesi, M.; Brau, J. E.; Breyer, J.; Briant, T.; Bridges, D. O.; Brillet, A.; Brinkmann, M.; Brisson, V.; Britzger, M.; Brooks, A. F.; Brown, D. A.; Bulik, T.; Bulten, H. J.; Buonanno, A.; Burguet-Castell, J.; Buskulic, D.; Buy, C.; Byer, R. L.; Cadonati, L.; Cagnoli, G.; Calloni, E.; Camp, J. B.; Campsie, P.; Cannizzo, J.; Cannon, K.; Canuel, B.; Cao, J.; Capano, C. D.; Carbognani, F.; Carbone, L.; Caride, S.; Caudill, S.; Cavaglià, M.; Cavalier, F.; Cavalieri, R.; Cella, G.; Cepeda, C.; Cesarini, E.; Chaibi, O.; Chalermsongsak, T.; Charlton, P.; Chassande-Mottin, E.; Chelkowski, S.; Chen, W.; Chen, X.; Chen, Y.; Chincarini, A.; Chiummo, A.; Cho, H. S.; Chow, J.; Christensen, N.; Chua, S. S. Y.; Chung, C. T. Y.; Chung, S.; Ciani, G.; Clara, F.; Clark, D. E.; Clark, J.; Clayton, J. H.; Cleva, F.; Coccia, E.; Cohadon, P.-F.; Colacino, C. N.; Colas, J.; Colla, A.; Colombini, M.; Conte, A.; Conte, R.; Cook, D.; Corbitt, T. R.; Cordier, M.; Cornish, N.; Corsi, A.; Costa, C. A.; Coughlin, M.; Coulon, J.-P.; Couvares, P.; Coward, D. M.; Cowart, M.; Coyne, D. C.; Creighton, J. D. E.; Creighton, T. D.; Cruise, A. M.; Cumming, A.; Cunningham, L.; Cuoco, E.; Cutler, R. M.; Dahl, K.; Danilishin, S. L.; Dannenberg, R.; D'Antonio, S.; Danzmann, K.; Dattilo, V.; Daudert, B.; Daveloza, H.; Davier, M.; Daw, E. J.; Day, R.; Dayanga, T.; De Rosa, R.; DeBra, D.; Debreczeni, G.; Del Pozzo, W.; del Prete, M.; Dent, T.; Dergachev, V.; DeRosa, R.; DeSalvo, R.; Dhurandhar, S.; Di Fiore, L.; Di Lieto, A.; Di Palma, I.; Emilio, M. Di Paolo; Di Virgilio, A.; Díaz, M.; Dietz, A.; Donovan, F.; Dooley, K. L.; Drago, M.; Drever, R. W. P.; Driggers, J. C.; Du, Z.; Dumas, J.-C.; Dwyer, S.; Eberle, T.; Edgar, M.; Edwards, M.; Effler, A.; Ehrens, P.; Endrőczi, G.; Engel, R.; Etzel, T.; Evans, K.; Evans, M.; Evans, T.; Factourovich, M.; Fafone, V.; Fairhurst, S.; Fan, Y.; Farr, B. F.; Fazi, D.; Fehrmann, H.; Feldbaum, D.; Feroz, F.; Ferrante, I.; Fidecaro, F.; Finn, L. S.; Fiori, I.; Fisher, R. P.; Flaminio, R.; Flanigan, M.; Foley, S.; Forsi, E.; Forte, L. A.; Fotopoulos, N.; Fournier, J.-D.; Franc, J.; Frasca, S.; Frasconi, F.; Frede, M.; Frei, M.; Frei, Z.; Freise, A.; Frey, R.; Fricke, T. T.; Friedrich, D.; Fritschel, P.; Frolov, V. V.; Fujimoto, M.-K.; Fulda, P. J.; Fyffe, M.; Gair, J.; Galimberti, M.; Gammaitoni, L.; Garcia, J.; Garufi, F.; Gáspár, M. E.; Gemme, G.; Geng, R.; Genin, E.; Gennai, A.; Gergely, L. Á.; Ghosh, S.; Giaime, J. A.; Giampanis, S.; Giardina, K. D.; Giazotto, A.; Gil-Casanova, S.; Gill, C.; Gleason, J.; Goetz, E.; Goggin, L. M.; González, G.; Gorodetsky, M. L.; Goßler, S.; Gouaty, R.; Graef, C.; Graff, P. B.; Granata, M.; Grant, A.; Gras, S.; Gray, C.; Gray, N.; Greenhalgh, R. J. S.; Gretarsson, A. M.; Greverie, C.; Grosso, R.; Grote, H.; Grunewald, S.; Guidi, G. M.; Guido, C.; Gupta, R.; Gustafson, E. K.; Gustafson, R.; Ha, T.; Hallam, J. M.; Hammer, D.; Hammond, G.; Hanks, J.; Hanna, C.; Hanson, J.; Harms, J.; Harry, G. M.; Harry, I. W.; Harstad, E. D.; Hartman, M. T.; Haughian, K.; Hayama, K.; Hayau, J.-F.; Heefner, J.; Heidmann, A.; Heintze, M. C.; Heitmann, H.; Hello, P.; Hendry, M. A.; Heng, I. S.; Heptonstall, A. W.; Herrera, V.; Hewitson, M.; Hild, S.; Hoak, D.; Hodge, K. A.; Holt, K.; Holtrop, M.; Hong, T.; Hooper, S.; Hosken, D. J.; Hough, J.; Howell, E. J.; Hughey, B.; Husa, S.; Huttner, S. H.; Huynh-Dinh, T.; Ingram, D. R.; Inta, R.; Isogai, T.; Ivanov, A.; Izumi, K.; Jacobson, M.; James, E.; Jang, Y. J.; Jaranowski, P.; Jesse, E.; Johnson, W. W.; Jones, D. I.; Jones, G.; Jones, R.; Ju, L.; Kalmus, P.; Kalogera, V.; Kandhasamy, S.

    2012-05-01

    Aims: The detection and measurement of gravitational-waves from coalescing neutron-star binary systems is an important science goal for ground-based gravitational-wave detectors. In addition to emitting gravitational-waves at frequencies that span the most sensitive bands of the LIGO and Virgo detectors, these sources are also amongst the most likely to produce an electromagnetic counterpart to the gravitational-wave emission. A joint detection of the gravitational-wave and electromagnetic signals would provide a powerful new probe for astronomy. Methods: During the period between September 19 and October 20, 2010, the first low-latency search for gravitational-waves from binary inspirals in LIGO and Virgo data was conducted. The resulting triggers were sent to electromagnetic observatories for followup. We describe the generation and processing of the low-latency gravitational-wave triggers. The results of the electromagnetic image analysis will be described elsewhere. Results: Over the course of the science run, three gravitational-wave triggers passed all of the low-latency selection cuts. Of these, one was followed up by several of our observational partners. Analysis of the gravitational-wave data leads to an estimated false alarm rate of once every 6.4 days, falling far short of the requirement for a detection based solely on gravitational-wave data.

  4. Measurement-based analysis of error latency. [in computer operating system

    Science.gov (United States)

    Chillarege, Ram; Iyer, Ravishankar K.

    1987-01-01

    This paper demonstrates a practical methodology for the study of error latency under a real workload. The method is illustrated with sampled data on the physical memory activity, gathered by hardware instrumentation on a VAX 11/780 during the normal workload cycle of the installation. These data are used to simulate fault occurrence and to reconstruct the error discovery process in the system. The technique provides a means to study the system under different workloads and for multiple days. An approach to determine the percentage of undiscovered errors is also developed and a verification of the entire methodology is performed. This study finds that the mean error latency, in the memory containing the operating system, varies by a factor of 10 to 1 (in hours) between the low and high workloads. It is found that of all errors occurring within a day, 70 percent are detected in the same day, 82 percent within the following day, and 91 percent within the third day. The increase in failure rate due to latency is not so much a function of remaining errors but is dependent on whether or not there is a latent error.

  5. Dusty plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Fortov, Vladimir E; Khrapak, Aleksei G; Molotkov, Vladimir I; Petrov, Oleg F [Institute for High Energy Densities, Associated Institute for High Temperatures, Russian Academy of Sciences, Moscow (Russian Federation); Khrapak, Sergei A [Max-Planck-Institut fur Extraterrestrische Physik, Garching (Germany)

    2004-05-31

    The properties of dusty plasmas - low-temperature plasmas containing charged macroparticles - are considered. The most important elementary processes in dusty plasmas and the forces acting on dust particles are investigated. The results of experimental and theoretical investigations of different states of strongly nonideal dusty plasmas - crystal-like, liquid-like, gas-like - are summarized. Waves and oscillations in dusty plasmas, as well as their damping and instability mechanisms, are studied. Some results on dusty plasma investigated under microgravity conditions are presented. New directions of experimental research and potential applications of dusty plasmas are discussed. (reviews of topical problems)

  6. Understanding Factors That Modulate the Establishment of HIV Latency in Resting CD4+ T-Cells In Vitro.

    Directory of Open Access Journals (Sweden)

    Jenny L Anderson

    Full Text Available Developing robust in vitro models of HIV latency is needed to better understand how latency is established, maintained and reversed. In this study, we examined the effects of donor variability, HIV titre and co-receptor usage on establishing HIV latency in vitro using two models of HIV latency. Using the CCL19 model of HIV latency, we found that in up to 50% of donors, CCL19 enhanced latent infection of resting CD4+ T-cells by CXCR4-tropic HIV in the presence of low dose IL-2. Increasing the infectious titre of CXCR4-tropic HIV increased both productive and latent infection of resting CD4+ T-cells. In a different model where myeloid dendritic cells (mDC were co-cultured with resting CD4+ T-cells, we observed a higher frequency of latently infected cells in vitro than CCL19-treated or unstimulated CD4+ T-cells in the presence of low dose IL-2. In the DC-T-cell model, latency was established with both CCR5- and CXCR4-tropic virus but higher titres of CCR5-tropic virus was required in most donors. The establishment of latency in vitro through direct infection of resting CD4+ T-cells is significantly enhanced by CCL19 and mDC, but the efficiency is dependent on virus titre, co-receptor usage and there is significant donor variability.

  7. Absolute neutrophil values in malignant patients on cytotoxic chemotherapy.

    Science.gov (United States)

    Madu, A J; Ibegbulam, O G; Ocheni, S; Madu, K A; Aguwa, E N

    2011-01-01

    A total of eighty patients with various malignancies seen between September 2008 and April 2009 at the University of Nigeria Teaching Hospital (UNTH) Ituku Ozalla, Enugu, Nigeria, had their absolute neutrophil counts, done at Days 0 and 12 of the first cycle of their various chemotherapeutic regimens. They were adult patients who had been diagnosed of various malignancies, consisting of Breast cancer 36 (45%), Non-Hodgkin's lymphoma 8 (10%), Hodgkin's lymphoma 13 (16.25%), Colorectal carcinoma 6 (7.5%), Multiple myeloma 7 (8.75%), Cervical carcinoma 1 (1.25%) and other malignancies 9 (11.25%), Manual counting of absolute neutrophil count was done using Turks solution and improved Neubauer counting chamber and Galen 2000 Olympus microscope. The socio demographic data of the patients were assessed from a questionnaire. There were 27 males (33.75%) and 53 females (66.25%). Their ages ranged from 18 - 80 years with a median of 45 years. The mean absolute neutrophil count of the respondents pre-and post chemotherapy was 3.7 +/- 2.1 x 10(9)/L and 2.5 +/- 1.6 x 10(9)/L respectively. There were significant differences in both the absolute neutrophil count (p=0.00) compared to the pre-chemotherapy values. Chemotherapeutic combinations containing cyclophosphamide and Adriamycin were observed to cause significant reduction in absolute neutrophil.

  8. Absolute quantification of somatic DNA alterations in human cancer.

    Science.gov (United States)

    Carter, Scott L; Cibulskis, Kristian; Helman, Elena; McKenna, Aaron; Shen, Hui; Zack, Travis; Laird, Peter W; Onofrio, Robert C; Winckler, Wendy; Weir, Barbara A; Beroukhim, Rameen; Pellman, David; Levine, Douglas A; Lander, Eric S; Meyerson, Matthew; Getz, Gad

    2012-05-01

    We describe a computational method that infers tumor purity and malignant cell ploidy directly from analysis of somatic DNA alterations. The method, named ABSOLUTE, can detect subclonal heterogeneity and somatic homozygosity, and it can calculate statistical sensitivity for detection of specific aberrations. We used ABSOLUTE to analyze exome sequencing data from 214 ovarian carcinoma tumor-normal pairs. This analysis identified both pervasive subclonal somatic point-mutations and a small subset of predominantly clonal and homozygous mutations, which were overrepresented in the tumor suppressor genes TP53 and NF1 and in a candidate tumor suppressor gene CDK12. We also used ABSOLUTE to infer absolute allelic copy-number profiles from 3,155 diverse cancer specimens, revealing that genome-doubling events are common in human cancer, likely occur in cells that are already aneuploid, and influence pathways of tumor progression (for example, with recessive inactivation of NF1 being less common after genome doubling). ABSOLUTE will facilitate the design of clinical sequencing studies and studies of cancer genome evolution and intra-tumor heterogeneity.

  9. Absolute frequency measurement of unstable lasers with optical frequency combs

    Science.gov (United States)

    Beverini, N.; Poli, N.; Sutyrin, D.; Wang, F.-Y.; Schioppo, M.; Tarallo, M. G.; Tino, G. M.

    2010-09-01

    Here we report on absolute frequency measurements of a commercial high power CW diode-pumped solid-state laser (Coherent Verdi-V5). This kind of lasers usually presents large frequency jitter (up to 50 MHz) both in the short term (1 ms time scale) and in the long term (>10 s time scale). A precise measurement of absolute frequency deviations in both temporal scales should require a set of different devices (optical cavities, optical wave-meters), each suited for measurements only at a specific integration time. Here we demonstrate how a frequency comb can be used to overcome this difficulty, allowing in a single step a full characterization of both short ( 103 s) absolute frequency jitter with a resolution better than 1 MHz. We demonstrate in this way the flexibility of optical frequency combs for absolute frequency measurements not only of ultra-stable lasers but also of relatively unstable lasers. The absolute frequency calibration of the Verdi laser that we have obtained have been used in order to improve the accuracy of the measurements of the local gravitational acceleration value with 88Sr atoms trapped in 1D vertical lattices.

  10. Absolute and relative family affluence and psychosomatic symptoms in adolescents.

    Science.gov (United States)

    Elgar, Frank J; De Clercq, Bart; Schnohr, Christina W; Bird, Phillippa; Pickett, Kate E; Torsheim, Torbjørn; Hofmann, Felix; Currie, Candace

    2013-08-01

    Previous research on the links between income inequality and health and socioeconomic differences in health suggests that relative differences in affluence impact health and well-being more than absolute affluence. This study explored whether self-reported psychosomatic symptoms in adolescents relate more closely to relative affluence (i.e., relative deprivation or rank affluence within regions or schools) than to absolute affluence. Data on family material assets and psychosomatic symptoms were collected from 48,523 adolescents in eight countries (Austria, Belgium, Canada, Norway, Scotland, Poland, Turkey, and Ukraine) as part of the 2009/10 Health Behaviour in School-aged Children study. Multilevel regression analyses of the data showed that relative deprivation (Yitzhaki Index, calculated in regions and in schools) and rank affluence (in regions) (1) related more closely to symptoms than absolute affluence, and (2) related to symptoms after differences in absolute affluence were held constant. However, differences in family material assets, whether they are measured in absolute or relative terms, account for a significant variation in adolescent psychosomatic symptoms. Conceptual and empirical issues relating to the use of material affluence indices to estimate socioeconomic position are discussed. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. Absolute Navigation Information Estimation for Micro Planetary Rovers

    Directory of Open Access Journals (Sweden)

    Muhammad Ilyas

    2016-03-01

    Full Text Available This paper provides algorithms to estimate absolute navigation information, e.g., absolute attitude and position, by using low power, weight and volume Microelectromechanical Systems-type (MEMS sensors that are suitable for micro planetary rovers. Planetary rovers appear to be easily navigable robots due to their extreme slow speed and rotation but, unfortunately, the sensor suites available for terrestrial robots are not always available for planetary rover navigation. This makes them difficult to navigate in a completely unexplored, harsh and complex environment. Whereas the relative attitude and position can be tracked in a similar way as for ground robots, absolute navigation information, unlike in terrestrial applications, is difficult to obtain for a remote celestial body, such as Mars or the Moon. In this paper, an algorithm called the EASI algorithm (Estimation of Attitude using Sun sensor and Inclinometer is presented to estimate the absolute attitude using a MEMS-type sun sensor and inclinometer, only. Moreover, the output of the EASI algorithm is fused with MEMS gyros to produce more accurate and reliable attitude estimates. An absolute position estimation algorithm has also been presented based on these on-board sensors. Experimental results demonstrate the viability of the proposed algorithms and the sensor suite for low-cost and low-weight micro planetary rovers.

  12. Evaluation of the relation between triceps surae H-reflex, M-response latencies and thigh length in normal population

    Directory of Open Access Journals (Sweden)

    Saeid Khosrawi

    2013-01-01

    Full Text Available Background: The H-reflex is a useful electrophysiological procedure for evaluating the status of the peripheral nervous system, especially at the proximal segment of the peripheral nerve. The purpose of this study is to investigate the relation between triceps surae H-reflex and M- response latencies and thigh length in normal population, in order to determine if there is any regression equation between them. Materials and Methods: After screening 75 volunteers by considering inclusion and exclusion criteria, 72 of them were selected to enroll into our study (34 men and 38 women with the mean age of 36.04 ± 7.7 years. In all of the subjects H-reflex and M-response latencies were recorded by standard electrophysiological techniques and thigh length was measured. Finally, our data was analyzed for its relations with respect to ages in both sexes by appropriate statistical and mathematical methods. Results: Mean ± SD for H-reflex latency was 27.94 ± 1.6 ms. We found a significant correlation between H-reflex latency and M-latency (r = 0.28, no significant correlation was found between H-reflex latency and thigh length (r = -0.051. Finally based on our findings we introduce a new formula in this paper.Conclusion: We found a significant correlation among of M-response latency and other variables (H-reflex latency and thigh length. Despite this it was eliminated from our formula. The relationship between H-reflex latency and age was significant. Further studies are required to delineate the clinical usage and interpretation of the formula, which we found in this study.

  13. [Decrease in N170 evoked potential component latency during repeated presentation of face images].

    Science.gov (United States)

    Verkhliutov, V M; Ushakov, V L; Strelets, V B

    2009-01-01

    The 15 healthy volunteers EEG from 28 channels was recorded during the presentation of visual stimuli in the form of face and building images. The stimuli were presented in two series. The first series consisted of 60 face and 60 building images presented in random order. The second series consisted of 30 face and 30 building images. The second series began 1.5-2 min after the end of the first ore. No instruction was given to the participants. P1, N170 and VPP EP components were identified for both stimuli categories. These components were located in the medial parietal area (Brodmann area 40). P1 and N170 components were recorded in the superior temporal fissure (Brodmann area 21, STS region), the first component had the latency 120 ms, the second one--155 ms. VPP was recorded with the latency 190 ms (Brodmann area 19). Dynamic mapping of EP components with the latency from 97 to 242 ms revealed the removal of positive maximums from occipital to frontal areas through temporal ones and their subsequent returning to occipital areas through the central ones. During the comparison of EP components to face and building images the amplitude differences were revealed in the following areas: P1--in frontal, central and anterior temporal areas, N170--in frontal, central, temporal and parietal areas, VPP--in all areas. It was also revealed that N170 latency was 12 ms shorter for face than for building images. It was proposed that the above mentioned N170 latency decrease for face in comparison with building images is connected with the different space location of the fusiform area responsible for face and building images recognition. Priming--the effect that is revealed during the repetitive face images presentation is interpreted as the manifestation of functional heterogeneity of the fusiform area responsible for the face images recognition. The hypothesis is put forward that the parts of extrastriate cortex which are located closer to the central retinotopical

  14. NEEMO 18-20: Analog Testing for Mitigation of Communication Latency During Human Space Exploration

    Science.gov (United States)

    Chappell, Steven P.; Beaton, Kara H.; Miller, Matthew J.; Graff, Trevor G.; Abercromby, Andrew F. J.; Gernhardt, Michael L.; Halcon, Christopher

    2016-01-01

    NASA Extreme Environment Mission Operations (NEEMO) is an underwater spaceflight analog that allows a true mission-like operational environment and uses buoyancy effects and added weight to simulate different gravity levels. Three missions were undertaken from 2014-2015, NEEMO's 18-20. All missions were performed at the Aquarius undersea research habitat. During each mission, the effects of communication latencies on operations concepts, timelines, and tasks were studied. METHODS: Twelve subjects (4 per mission) were weighed out to simulate near-zero or partial gravity extravehicular activity (EVA) and evaluated different operations concepts for integration and management of a simulated Earth-based science team (ST) to provide input and direction during exploration activities. Exploration traverses were preplanned based on precursor data. Subjects completed science-related tasks including pre-sampling surveys, geologic-based sampling, and marine-based sampling as a portion of their tasks on saturation dives up to 4 hours in duration that were designed to simulate extravehicular activity (EVA) on Mars or the moons of Mars. One-way communication latencies, 5 and 10 minutes between space and mission control, were simulated throughout the missions. Objective data included task completion times, total EVA times, crew idle time, translation time, ST assimilation time (defined as time available for ST to discuss data/imagery after data acquisition). Subjective data included acceptability, simulation quality, capability assessment ratings, and comments. RESULTS: Precursor data can be used effectively to plan and execute exploration traverse EVAs (plans included detailed location of science sites, high-fidelity imagery of the sites, and directions to landmarks of interest within a site). Operations concepts that allow for pre-sampling surveys enable efficient traverse execution and meaningful Mission Control Center (MCC) interaction across communication latencies and can be

  15. A hundred years of latency: from Freudian psychosexual theory to dynamic systems nonlinear development in middle childhood.

    Science.gov (United States)

    Knight, Rona

    2014-04-01

    A focus on the latency phase is used to illustrate how theory and developmental research have influenced our psychoanalytic views of development over the past hundred years. Beginning with Freud's psychosexual theory and his conception of latency, an historical overview of the major psychoanalytic contributions bearing on this developmental period over the past century is presented. Recent longitudinal research in latency supports a nonlinear dynamic systems approach to development. This approach obliges us to reconsider our linear theories and how we think about and work with our patients.

  16. Absolute distance sensing by two laser optical interferometry.

    Science.gov (United States)

    Thurner, Klaus; Braun, Pierre-François; Karrai, Khaled

    2013-11-01

    We have developed a method for absolute distance sensing by two laser optical interferometry. A particularity of this technique is that a target distance is determined in absolute and is no longer limited to within an ambiguity range affecting usually multiple wavelength interferometers. We implemented the technique in a low-finesse Fabry-Pérot miniature fiber based interferometer. We used two diode lasers, both operating in the 1550 nm wavelength range. The wavelength difference is chosen to create a 25 μm long periodic beating interferometric pattern allowing a nanometer precise position measurement but limited to within an ambiguity range of 25 μm. The ambiguity is then eliminated by scanning one of the wavelengths over a small range (3.4 nm). We measured absolute distances in the sub-meter range and this with just few nanometer repeatability.

  17. Abelian varieties with many endomorphisms and their absolutely simple factors

    CERN Document Server

    Guitart, Xavier

    2011-01-01

    We characterize the abelian varieties arising as absolutely simple factors of GL2-type varieties over a number field k. In order to obtain this result, we study a wider class of abelian varieties: the k-varieties A/k satisfying that $\\End_k^0(A)$ is a maximal subfield of $\\End_k^0(A)$. We call them Ribet-Pyle varieties over k. We see that every Ribet-Pyle variety over k is isogenous over $\\bar k$ to a power of an abelian k-variety and, conversely, that every abelian k-variety occurs as the absolutely simple factor of some Ribet-Pyle variety over k. We deduce from this correspondence a precise description of the absolutely simple factors of the varieties over k of GL2-type.

  18. Absolute Uniqueness of Phase Retrieval with Random Illumination

    CERN Document Server

    Fannjiang, Albert

    2011-01-01

    Random phase or amplitude illumination is proposed to remove at once all types of ambiguity, trivial or nontrivial, at once from phase retrieval. Almost sure irreducibility is proved for {\\em any} complex-valued object of arbitrary sparsity. While this irreducibility result can be viewed as a probabilistic version of the classical result by Bruck, Sodin and Hayes, it provides a new perspective and an effective method for achieving absolute uniqueness in phase retrieval for {\\em every} object, not just objects outside of a measure-zero set. In particular, almost sure absolute uniqueness is proved for complex-valued objects under a general two-point assumption. For objects of nonnegative real and imaginary parts, absolute uniqueness is proved to hold with probability exponentially close to unity as the object sparsity increases.

  19. The mixed Littlewood conjecture for pseudo-absolute values

    CERN Document Server

    Harrap, Stephen

    2010-01-01

    In this paper we prove the mixed Littlewood conjecture for a p-adic absolute value and any pseudo-absolute value with bounded ratios. More precisely we show that if p is a prime and D is a pseudo-absolute value sequence with elements divisible by finitely many primes not equal to p, and if the terms of D grow more slowly than the exponential of a polynomial then the infimum over natural numbers n of the quantity n.|n|_p.|n|_D.||nx|| equals 0 for all real x. Our proof relies on two deep results, a measure rigidity theorem due to Lindenstrauss and lower bounds for linear forms in logarithms due to Baker and Wustholz. We also deduce the answer to the related metric question of how fast the infimum above tends to zero, for almost every x.

  20. Determination of absolute adsorption in highly ordered porous media

    Science.gov (United States)

    Mertens, Florian O.

    2009-06-01

    Recently developed Metal Organic Frameworks (MOFs) are the materials with the highest intrinsic surface areas to date and their discovery increased the research activity in the field of microporous adsorption materials significantly. In this contribution, a generic method of analysis for volumetrically measured adsorption isotherms is presented that separates absolute adsorption from excess adsorption to the best possible degree by representing the absolute adsorption isotherm by a superposition of in respect to pressure strictly monotonously increasing fitting function. The procedure allows to determine the heat of adsorption at constant gas uptake via implicitly defined quantities. The method was applied to adsorption data of hydrogen on MOF-5 ranging from 40 K to 200 K. Methane adsorption on MOF-5 was used to demonstrate that the common practice of neglecting the difference between excess and absolute adsorption leads to erroneously increased heat of adsorption values at high coverages and temperatures.

  1. Absolute and Relative Socioeconomic Health Inequalities across Age Groups.

    Directory of Open Access Journals (Sweden)

    Sander K R van Zon

    Full Text Available The magnitude of socioeconomic health inequalities differs across age groups. It is less clear whether socioeconomic health inequalities differ across age groups by other factors that are known to affect the relation between socioeconomic position and health, like the indicator of socioeconomic position, the health outcome, gender, and as to whether socioeconomic health inequalities are measured in absolute or in relative terms. The aim is to investigate whether absolute and relative socioeconomic health inequalities differ across age groups by indicator of socioeconomic position, health outcome and gender.The study sample was derived from the baseline measurement of the LifeLines Cohort Study and consisted of 95,432 participants. Socioeconomic position was measured as educational level and household income. Physical and mental health were measured with the RAND-36. Age concerned eleven 5-years age groups. Absolute inequalities were examined by comparing means. Relative inequalities were examined by comparing Gini-coefficients. Analyses were performed for both health outcomes by both educational level and household income. Analyses were performed for all age groups, and stratified by gender.Absolute and relative socioeconomic health inequalities differed across age groups by indicator of socioeconomic position, health outcome, and gender. Absolute inequalities were most pronounced for mental health by household income. They were larger in younger than older age groups. Relative inequalities were most pronounced for physical health by educational level. Gini-coefficients were largest in young age groups and smallest in older age groups.Absolute and relative socioeconomic health inequalities differed cross-sectionally across age groups by indicator of socioeconomic position, health outcome and gender. Researchers should critically consider the implications of choosing a specific age group, in addition to the indicator of socioeconomic position and

  2. Neural Sensitivity to Absolute and Relative Anticipated Reward in Adolescents

    Science.gov (United States)

    Vaidya, Jatin G.; Knutson, Brian; O'Leary, Daniel S.; Block, Robert I.; Magnotta, Vincent

    2013-01-01

    Adolescence is associated with a dramatic increase in risky and impulsive behaviors that have been attributed to developmental differences in neural processing of rewards. In the present study, we sought to identify age differences in anticipation of absolute and relative rewards. To do so, we modified a commonly used monetary incentive delay (MID) task in order to examine brain activity to relative anticipated reward value (neural sensitivity to the value of a reward as a function of other available rewards). This design also made it possible to examine developmental differences in brain activation to absolute anticipated reward magnitude (the degree to which neural activity increases with increasing reward magnitude). While undergoing fMRI, 18 adolescents and 18 adult participants were presented with cues associated with different reward magnitudes. After the cue, participants responded to a target to win money on that trial. Presentation of cues was blocked such that two reward cues associated with $.20, $1.00, or $5.00 were in play on a given block. Thus, the relative value of the $1.00 reward varied depending on whether it was paired with a smaller or larger reward. Reflecting age differences in neural responses to relative anticipated reward (i.e., reference dependent processing), adults, but not adolescents, demonstrated greater activity to a $1 reward when it was the larger of the two available rewards. Adults also demonstrated a more linear increase in ventral striatal activity as a function of increasing absolute reward magnitude compared to adolescents. Additionally, reduced ventral striatal sensitivity to absolute anticipated reward (i.e., the difference in activity to medium versus small rewards) correlated with higher levels of trait Impulsivity. Thus, ventral striatal activity in anticipation of absolute and relative rewards develops with age. Absolute reward processing is also linked to individual differences in Impulsivity. PMID:23544046

  3. Absolute small-angle measurement based on optical feedback interferometry

    Institute of Scientific and Technical Information of China (English)

    Jingang Zhong; Xianhua Zhang; Zhixiang Ju

    2008-01-01

    We present a simple but effective method for small-angle measurement based on optical feedback inter-ferometry (or laser self-mixing interferometry). The absolute zero angle can be defined at the biggest fringe amplitude point, so this method can also achieve absolute angle measurement. In order to verify the method, we construct an angle measurement system. The Fourier-transform method is used to analysis the interference signal. Rotation angles are experimentally measured with a resolution of 10-6 rad and a measurement range of approximately from -0.0007 to +0.0007 rad.

  4. Improved Absolute Radiometric Calibration of a UHF Airborne Radar

    Science.gov (United States)

    Chapin, Elaine; Hawkins, Brian P.; Harcke, Leif; Hensley, Scott; Lou, Yunling; Michel, Thierry R.; Moreira, Laila; Muellerschoen, Ronald J.; Shimada, Joanne G.; Tham, Kean W.; hide

    2015-01-01

    The AirMOSS airborne SAR operates at UHF and produces fully polarimetric imagery. The AirMOSS radar data are used to produce Root Zone Soil Moisture (RZSM) depth profiles. The absolute radiometric accuracy of the imagery, ideally of better than 0.5 dB, is key to retrieving RZSM, especially in wet soils where the backscatter as a function of soil moisture function tends to flatten out. In this paper we assess the absolute radiometric uncertainty in previously delivered data, describe a method to utilize Built In Test (BIT) data to improve the radiometric calibration, and evaluate the improvement from applying the method.

  5. Absolute, Extreme-Ultraviolet, Solar Spectral Irradiance Monitor (AESSIM)

    Science.gov (United States)

    Huber, Martin C. E.; Smith, Peter L.; Parkinson, W. H.; Kuehne, M.; Kock, M.

    1988-01-01

    AESSIM, the Absolute, Extreme-Ultraviolet, Solar Spectral Irradiance Monitor, is designed to measure the absolute solar spectral irradiance at extreme-ultraviolet (EUV) wavelengths. The data are required for studies of the processes that occur in the earth's upper atmosphere and for predictions of atmospheric drag on space vehicles. AESSIM is comprised of sun-pointed spectrometers and newly-developed, secondary standards of spectral irradiance for the EUV. Use of the in-orbit standard sources will eliminate the uncertainties caused by changes in spectrometer efficiency that have plagued all previous measurements of the solar spectral EUV flux.

  6. Properties of Absolute Stability in the Presence of Time Lags

    Directory of Open Access Journals (Sweden)

    M. De la Sen

    2005-01-01

    Full Text Available This study is concerned with the properties of absolute stability independent of the delays of time-delay systems, possessing non commensurate internal point delays, for any nonlinearity satisfying a Popov’s- type time positivity inequality. That property holds if an associate delay-free system is absolutely stable and the size of the delayed dynamics is sufficiently small. The results are obtained for nonlinearities belonging to sectors [0, k] and [h, k+h], and are based on a parabola test type.

  7. Stability comparison of two absolute gravimeters: optical versus atomic interferometers

    CERN Document Server

    Gillot, Pierre; Landragin, Arnaud; Santos, Franck Pereira Dos; Merlet, Sébastien

    2014-01-01

    We report the direct comparison between the stabilities of two mobile absolute gravimeters of different technology: the LNE-SYRTE Cold Atom Gravimeter and FG5X\\#216 of the Universit\\'e du Luxembourg. These instruments rely on two different principles of operation: atomic and optical interferometry. The comparison took place in the Walferdange Underground Laboratory for Geodynamics in Luxembourg, at the beginning of the last International Comparison of Absolute Gravimeters, ICAG-2013. We analyse a 2h10 duration common measurement, and find that the CAG shows better immunity with respect to changes in the level of vibration noise, as well as a slightly better short term stability.

  8. Absolute cross-sections from X-{gamma} coincidence measurements

    Energy Technology Data Exchange (ETDEWEB)

    Lemasson, A. [GANIL, CEA/DSM - CNRS/IN2P3, Bd Henri Becquerel, BP 55027, F-14076 Caen Cedex 5 (France); Shrivastava, A. [Nuclear Physics Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Navin, A. [GANIL, CEA/DSM - CNRS/IN2P3, Bd Henri Becquerel, BP 55027, F-14076 Caen Cedex 5 (France)], E-mail: navin@ganil.fr; Rejmund, M. [GANIL, CEA/DSM - CNRS/IN2P3, Bd Henri Becquerel, BP 55027, F-14076 Caen Cedex 5 (France); Nanal, V. [Department of Nuclear and Atomic Physics, Tata Institute of Fundamental Research, Mumbai 400005 (India); Bhattacharyya, S. [Variable Energy Cyclotron Centre, 1/AF Bidhan Nagar, Kolkata 700064 (India); Chatterjee, A.; Kailas, S.; Mahata, K.; Parkar, V.V. [Nuclear Physics Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Pillay, R.G. [Department of Nuclear and Atomic Physics, Tata Institute of Fundamental Research, Mumbai 400005 (India); Ramachandran, K.; Rout, P.C. [Nuclear Physics Division, Bhabha Atomic Research Centre, Mumbai 400085 (India)

    2009-01-11

    An activation technique using coincidences between characteristic X-rays and {gamma}-rays to obtain absolute cross-sections is described. This method is particularly useful in the case of nuclei that decay by electron capture. In addition to the reduction of possible contamination, an improved detection sensitivity is achieved as compared to inclusive measurements, thereby allowing the extraction of absolute fusion cross-sections in the nano-barn range. Results of this technique for {sup 6}Li+{sup 198}Pt system, at energies around the Coulomb barrier are described. Future applications with low intensity radioactive ion beams are also discussed.

  9. Total Synthesis and Absolute Configuration of the Marine Norditerpenoid Xestenone

    Directory of Open Access Journals (Sweden)

    Hiroaki Miyaoka

    2009-11-01

    Full Text Available Xestenone is a marine norditerpenoid found in the northeastern Pacific sponge Xestospongia vanilla. The relative configuration of C-3 and C-7 in xestenone was determined by NOESY spectral analysis. However the relative configuration of C-12 and the absolute configuration of this compound were not determined. The authors have now achieved the total synthesis of xestenone using their developed one-pot synthesis of cyclopentane derivatives employing allyl phenyl sulfone and an epoxy iodide as a key step. The relative and absolute configurations of xestenone were thus successfully determined by this synthesis.

  10. A Comparison Between House Mouse Lines Selected for Attack Latency or Nest-Building : Evidence for a Genetic Basis of Alternative Behavioral Strategies

    NARCIS (Netherlands)

    Sluyter, Frans; Bult, Abel; Lynch, Carol B.; Oortmerssen, Geert A. van; Koolhaas, Jaap M.

    1995-01-01

    House mouse lines bidirectionally selected for either nest-building behavior or attack latency were tested for both attack latency and nest-building behavior under identical conditions. Male mice selected for high nest-building behavior had shorter attack latencies, i.e., were more aggressive, than

  11. Plasma waves

    CERN Document Server

    Swanson, DG

    1989-01-01

    Plasma Waves discusses the basic development and equations for the many aspects of plasma waves. The book is organized into two major parts, examining both linear and nonlinear plasma waves in the eight chapters it encompasses. After briefly discussing the properties and applications of plasma wave, the book goes on examining the wave types in a cold, magnetized plasma and the general forms of the dispersion relation that characterize the waves and label the various types of solutions. Chapters 3 and 4 analyze the acoustic phenomena through the fluid model of plasma and the kinetic effects. Th

  12. Plasma astrophysics

    CERN Document Server

    Kaplan, S A; ter Haar, D

    2013-01-01

    Plasma Astrophysics is a translation from the Russian language; the topics discussed are based on lectures given by V.N. Tsytovich at several universities. The book describes the physics of the various phenomena and their mathematical formulation connected with plasma astrophysics. This book also explains the theory of the interaction of fast particles plasma, their radiation activities, as well as the plasma behavior when exposed to a very strong magnetic field. The text describes the nature of collective plasma processes and of plasma turbulence. One author explains the method of elementary

  13. Acquired absolute vitamin K deficiency in a patient undergoing warfarin therapy.

    Science.gov (United States)

    Takada, Hiroaki; Toru, Hifumi; Bunya, Naofumi; Kiriu, Nobuaki; Kato, Hiroshi; Koido, Yuichi; Yasuhiro, Kuroda

    2014-06-01

    We report a case of absolute vitamin K deficiency (VKD) diagnosed by measuring serum VK levels in an elderly woman undergoing warfarin therapy. A 78-year-old woman was admitted to our hospital because of dyspnea and sore throat diagnosed as pharyngitis 1 week before admission. On admission, the sore throat had exacerbated and dyspnea developed. She had history of atrial fibrillation, for which warfarin 1.5 mg/d was started approximately 10 years prior and her international normalized ratio (INR) had been maintained at an acceptable therapeutic level. Blood results revealed unmeasurable INR and abnormally prolonged activated partial thromboplastin time (APTT). She was diagnosed with adenoiditis and warfarin-related coagulopathy and administered intravenous VK (20 mg) and fresh frozen plasma (FFP; 4 U), which improved INR and APTT. Since the coagulopathy responded to intravenous VK administration, the patient was clinically diagnosed with warfarin-related relative VKD. Approximately 1 month later, she returned with complaints of sore throat. Blood results indicated abnormal INR (7.22) and APTT (N80.0 s). She was diagnosed with recurrent adenoiditis and VK deficient coagulopathy. The patient’s serum VK levels were low (VK1 level, 0.13 ng/mL; VK2 levels, 0.85 ng/mL). Initial treatment of VK (20 mg) and FFP followed by intravenous VK (20 mg/d) for 6 days, her symptoms dissipated. Warfarin was suspected to have caused absolute VKD. Severe coagulopathy in patients undergoing warfarin therapy is primarily caused by, relative VKD. However, the possibility of warfarin-related absolute VKD should be suspected when INRis not sufficiently improved by intravenous VK administration.

  14. Preliminary results of absolute wavelength calibration of imaging X-ray crystal spectrometer on EAST

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Xiayun [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); University of Science and Technology of China, Hefei 230026 (China); Wang, Fudi [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Chen, Jun [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); University of Science and Technology of China, Hefei 230026 (China); Lyu, Bo, E-mail: blu@ipp.ac.cn [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Li, Yingying; Fu, Jia; Xu, Liqing [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Shi, Yuejiang [University of Science and Technology of China, Hefei 230026 (China); Department of Nuclear Engineering, Seoul National University, Seoul 151-742 (Korea, Republic of); Ye, Minyou [University of Science and Technology of China, Hefei 230026 (China); Wan, Baonian [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China)

    2015-10-15

    Highlights: • The absolute wavelength calibration method for X-ray crystal spectrometer using X-ray fluorescence of the appropriate materials was first tested on EAST, and the preliminary experimental results were obtained. • The experimental results were thoroughly discussed and suggestion for further improvements of the experimental arrangement was proposed. • Rotation calibration of X-ray crystal spectrometer on EAST using MHD frequency was presented when the absolute wavelength calibration method is unavailable currently. - Abstract: Imaging X-ray crystal spectrometers (XCS) are currently operating on several major tokamaks to provide profiles of ion temperature and rotation velocity. In order to acquire absolute rotation velocity, several indirect methods were pursued previously, however the direct and effective method is to use known X-ray lines for wavelength calibration. One way to produce standard spectral lines is X-ray fluorescence, which could be excited by X-rays from tokamak plasmas. As part of the upgrade of XCS system on EAST, wavelength calibration was studied using cadmium's L-shell lines, namely Lα{sub 1} line (3.9564 Å) and Lα{sub 2} line (3.9650 Å) as the reference wavelength. The Geant 4 code was used to optimize foil thickness to achieve a reasonable X-ray fluorescence intensity. The Cd foil was placed between the beryllium window and crystal and could be retracted to provide in situ wavelength calibration. The detailed arrangement and preliminary wavelength calibration results of imaging X-ray crystal spectrometer on EAST are presented, plus the calibration using MHD frequency.

  15. Residue iteration decomposition (RIDE): A new method to separate ERP components on the basis of latency variability in single trials.

    Science.gov (United States)

    Ouyang, Guang; Herzmann, Grit; Zhou, Changsong; Sommer, Werner

    2011-12-01

    Event-related brain potentials (ERPs) are important research tools because they provide insights into mental processing at high temporal resolution. Their usefulness, however, is limited by the need to average over a large number of trials, sacrificing information about the trial-by-trial variability of latencies or amplitudes of specific ERP components. Here we propose a novel method based on an iteration strategy of the residues of averaged ERPs (RIDE) to separate latency-variable component clusters. The separated component clusters can then serve as templates to estimate latencies in single trials with high precision. By applying RIDE to data from a face-priming experiment, we separate priming effects and show that they are robust against latency shifts and within-condition variability. RIDE is useful for a variety of data sets that show different degrees of variability and temporal overlap between ERP components.

  16. Effect of magnesium sulfate administration for neuroprotection on latency in women with preterm premature rupture of membranes.

    LENUS (Irish Health Repository)

    Horton, Amanda L

    2015-03-01

    This study aims to evaluate whether magnesium sulfate administration for neuroprotection prolongs latency in women with preterm premature rupture of membranes (PPROM) between 24 and 31(6\\/7) weeks\\' gestation.

  17. Outcomes of a NASA Workshop to Develop a Portfolio of Low Latency Datasets for Time-Sensitive Applications

    Science.gov (United States)

    Davies, Diane K.; Brown, Molly E.; Green, David S.; Michael, Karen A.; Murray, John J.; Justice, Christopher O.; Soja, Amber J.

    2016-01-01

    It is widely accepted that time-sensitive remote sensing data serve the needs of decision makers in the applications communities and yet to date, a comprehensive portfolio of NASA low latency datasets has not been available. This paper will describe the NASA low latency, or Near-Real Time (NRT), portfolio, how it was developed and plans to make it available online through a portal that leverages the existing EOSDIS capabilities such as the Earthdata Search Client (https:search.earthdata.nasa.gov), the Common Metadata Repository (CMR) and the Global Imagery Browse Service (GIBS). This paper will report on the outcomes of a NASA Workshop to Develop a Portfolio of Low Latency Datasets for Time-Sensitive Applications (27-29 September 2016 at NASA Langley Research Center, Hampton VA). The paper will also summarize findings and recommendations from the meeting outlining perceived shortfalls and opportunities for low latency research and application science.

  18. Influence of gap and overlap paradigms on saccade latencies and vergence eye movements in seven-year-old children.

    Science.gov (United States)

    Bucci, Maria Pia; Pouvreau, Nathalie; Yang, Qing; Kapoula, Zoï

    2005-07-01

    The latency of eye movements is influenced by the fixation task; when the fixation stimulus is switched off before the target presentation (gap paradigm) the latency becomes short and express movements occur. In contrast, when the fixation stimulus remains on when the target appears (overlap paradigm), eye movement latency is longer. Several previous studies have shown increased rates of express saccades in children; however the presence of an express type of latency for vergence and combined movements in children has never been explored. The present study examines the effects of the gap and the overlap paradigms on horizontal saccades at far (150 cm) and at close (20 cm) viewing distances, on vergence along the median plane, and on saccades combined with convergence or divergence in 15 normal seven-year-old children. The results show that the gap paradigm produced shorter latency for all eye movements than the overlap paradigm, but the difference was only significant for saccades at close viewing distances, for divergence (pure and combined), and for saccades combined with vergence. The gap paradigm produced significantly higher rates of express latencies for saccades at close viewing distances, for divergence, and for saccades combined with divergence; in contrast, the frequencies of express latencies for saccades at far viewing distances and for convergence (pure or combined) were similar in the gap and the overlap paradigms. Interestingly, the rate of anticipatory latencies (gap paradigm. Our collective findings suggest that the initiation of saccades at close viewing distances and of divergence is more reflexive, particularly in the gap paradigm. The finding of frequent anticipatory divergence that occurs at similar rates for seven-year-old children (this study) and for adults (Coubard et al., 2004, Exp Brain Res 154:368-381) indicates that predictive initiation of divergence is dominant.

  19. First absolutely calibrated on-axis ion flow measurements in MST

    Science.gov (United States)

    Schott, B.; Baltzer, M.; Craig, D.; den Hartog, D. J.; Nishizawa, T.; Nornberg, M. D.

    2016-10-01

    Improvements in absolute calibration techniques allow for the first direct measurements of the flow profile in the core of MST. We use both active charge exchange recombination spectroscopy and passive emission near 343 nm to measure ion temperature and flow. It is generally assumed that O VI is the brightest passive emission source. However, we show that there are cases, such as high temperature, pulsed poloidal current drive (PPCD) plasmas where the passive emission is dominated by C VI. Differences in the fine structure for O VI and C VI result in a systematic velocity error of about 12 km/s if the wrong model is assumed. Active measurements, however, are relatively insensitive to background model choice. The dominant source of error in active velocity measurements remains the systematic errors in calibration. The first absolutely calibrated, localized toroidal velocity measurements were obtained using an updated calibration technique. During PPCD, the on-axis ion flow is up to 40 km/s larger than both the n = 6 mode velocity and the line-averaged ion velocity. These measurements provide the first direct look at the flow profile in the core of MST. This work has been supported by the US DOE and the Wheaton College summer research program.

  20. [ABSOLUTE AND RELATIVE BIOAVAILABILITY OF GLUTARON--A NEW DERIVATIVE OF GLUTAMIC ACID].

    Science.gov (United States)

    Smirnova, L A; Ryabukha, A F; Kuznetsov, K A; Suchkov, E A; Perfilova, V N; Tyurenkov, I N

    2015-01-01

    The pharmacokinetics of studies of 3-phenylglutamic acid hydrochloride (glutaron) has been studied in rats. The main pharmacokinetic parameters show low values of the half-life (T1/2 = 3.75 h), mean retention time in the body (MRT = 5.77 h). The medium rate of drug concentration decrease in the blood plasma leads to a low value of the area under pharmacokinetic curve (AUC = 41.18 mg · h/mL). The general volume of distribution (Vd = 3.42 L/kg) is 3.5 times greater than the volume of extracellular fluid in the rat body. These data indicate a high ability of the glutaron to be distributed and accumulated in animal tissues. The value of absolute bioavailability is 84%, and the relative bioavailabity is 100%.