Enhanced sensitivity to dielectric function and thickness of absorbing thin films by combining total internal reflection ellipsometry with standard ellipsometry and reflectometry

NASA Astrophysics Data System (ADS)

Lizana, A.; Foldyna, M.; Stchakovsky, M.; Georges, B.; Nicolas, D.; Garcia-Caurel, E.

2013-03-01

High sensitivity of spectroscopic ellipsometry and reflectometry for the characterization of thin films can strongly decrease when layers, typically metals, absorb a significant fraction of the light. In this paper, we propose a solution to overcome this drawback using total internal reflection ellipsometry (TIRE) and exciting a surface longitudinal wave: a plasmon-polariton. As in the attenuated total reflectance technique, TIRE exploits a minimum in the intensity of reflected transversal magnetic (TM) polarized light and enhances the sensitivity of standard methods to thicknesses of absorbing films. Samples under study were stacks of three films, ZnO : Al/Ag/ZnO : Al, deposited on glass substrates. The thickness of the silver layer varied from sample to sample. We performed measurements with a UV-visible phase-modulated ellipsometer, an IR Mueller ellipsometer and a UV-NIR reflectometer. We used the variance-covariance formalism to evaluate the sensitivity of the ellipsometric data to different parameters of the optical model. Results have shown that using TIRE doubled the sensitivity to the silver layer thickness when compared with the standard ellipsometry. Moreover, the thickness of the ZnO : Al layer below the silver layer can be reliably quantified, unlike for the fit of the standard ellipsometry data, which is limited by the absorption of the silver layer.

Infrared-spectroscopic single-shot laser mapping ellipsometry: Proof of concept for fast investigations of structured surfaces and interactions in organic thin films

NASA Astrophysics Data System (ADS)

Furchner, Andreas; Kratz, Christoph; Gkogkou, Dimitra; Ketelsen, Helge; Hinrichs, Karsten

2017-11-01

We present a novel infrared-spectroscopic laser mapping ellipsometer based on a single-shot measurement concept. The ellipsometric set-up employs multiple analyzers and detectors to simultaneously measure the sample's optical response under different analyzer azimuths. An essential component is a broadly tunable quantum cascade laser (QCL) covering the important marker region of 1800-1540 cm-1. The ellipsometer allows for fast single-wavelength as well as spectroscopic studies with thin-film sensitivity at temporal resolutions of 60 ms per wavelength. We applied the single-shot mapping ellipsometer for the characterization of metal-island enhancement surfaces as well as of molecular interactions in organic thin films. In less than 3 min, a linescan with 1600 steps revealed profile and infrared-enhancement properties of a gradient gold-island film for sensing applications. Spectroscopic measurements were performed to probe the amide I band of thin films of poly(N-isopropylacrylamide) [PNIPAAm], a stimuli-responsive polymer for bioapplications. The QCL spectra agree well with conventional FT-IR ellipsometric results, showing different band components associated with hydrogen-bond interactions between polymer and adsorbed water. Multi-wavelength ellipsometric maps were used to analyze homogeneity and surface contaminations of the polymer films.

Electrochemical impedance spectroscopy based-on interferon-gamma detection

NASA Astrophysics Data System (ADS)

Li, Guan-Wei; Kuo, Yi-Ching; Tsai, Pei-I.; Lee, Chih-Kung

2014-03-01

Tuberculosis (TB) is an ancient disease constituted a long-term menace to public health. According to World Health Organization (WHO), mycobacterium tuberculosis (MTB) infected nearly a third of people of the world. There is about one new TB occurrence every second. Interferon-gamma (IFN-γ) is associated with susceptibility to TB, and interferongamma release assays (IGRA) is considered to be the best alternative of tuberculin skin test (TST) for diagnosis of latent tuberculosis infection (LTBI). Although significant progress has been made with regard to the design of enzyme immunoassays for IFN-γ, adopting this assay is still labor-intensive and time-consuming. To alleviate these drawbacks, we used IFN-γ antibody to facilitate the detection of IFN-γ. An experimental verification on the performance of IGRA was done in this research. We developed two biosensor configurations, both of which possess high sensitivity, specificity, and rapid IFN-γ diagnoses. The first is the electrochemical method. The second is a circular polarization interferometry configuration, which incorporates two light beams with p-polarization and s-polarization states individually along a common path, a four photo-detector quadrature configuration to arrive at a phase modulated ellipsometer. With these two methods, interaction between IFN-γ antibody and IFN-γ were explored and presented in detail.

Optical characterization of Mg-doped ZnO thin films deposited by RF magnetron sputtering technique

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

Singh, Satyendra Kumar; Tripathi, Shweta; Hazra, Purnima

2016-05-06

This paper reports the in-depth analysis on optical characteristics of magnesium (Mg) doped zinc oxide (ZnO) thin films grown on p-silicon (Si) substrates by RF magnetron sputtering technique. The variable angle ellipsometer is used for the optical characterization of as-deposited thin films. The optical reflectance, transmission spectra and thickness of as-deposited thin films are measured in the spectral range of 300-800 nm with the help of the spectroscopic ellipsometer. The effect of Mg-doping on optical parameters such as optical bandgap, absorption coefficient, absorbance, extinction coefficient, refractive Index and dielectric constant for as-deposited thin films are extracted to show its application inmore » optoelectronic and photonic devices.« less

Interface plasmonic properties of silver coated by ultrathin metal oxides

NASA Astrophysics Data System (ADS)

Sytchkova, A.; Zola, D.; Grilli, M. L.; Piegari, A.; Fang, M.; He, H.; Shao, J.

2011-09-01

Many fields of high technology take advantage of conductor-dielectric interface properties. Deeper knowledge of physical processes that determine the optical response of the structures containing metal-dielectric interfaces is important for improving the performance of thin film devices containing such materials. Here we present a study on optical properties of several ultrathin metal oxides deposited over thin silver layers. Some widely used materials (Al2O3, SiO2, Y2O3, HfO2) were selected for deposition by r.f. sputtering, and the created metal-dielectric structures with two of them, alumina and silica, were investigated in this work using attenuated total reflectance (ATR) technique and by variable-angle spectroscopic ellipsometry (VASE). VASE was performed with a help of a commercial ellipsometer at various incident angles and in a wide spectral range. A home-made sample holder manufactured for WVASE ellipsometer and operational in Otto configuration has been implemented for angle-resolved and spectral ATR measurements. Simultaneous analysis of data obtained by these two independent techniques allows elaboration of a representative model for plasmonic-related phenomena at metal-dielectric interface. The optical constants of the interface layers formed between metal and ultrathin oxide layers are investigated. A series of oxides chosen for this study allows a comparative analysis aimed for selection of the most appropriate materials for different applications.

Characterization facility for magneto-optic media and systems

NASA Technical Reports Server (NTRS)

Mansuripur, M.; Fu, H.; Gadetsky, S.; Sugaya, S.; Wu, T. H.; Zambuto, J.; Gerber, R.; Goodman, T.; Erwin, J. K.

1993-01-01

Objectives of this research are: (1) to measure the hysteresis loop, Kerr rotation angle, anisotropy energy profile, Hall voltage, and magnetoresistance of thin-film magneto-optic media using our loop-tracer; (2) measure the wavelength-dependence of the Kerr rotation angle, Theta(sub k), and ellipticity, epsilon(sub k), for thin-film media using our magneto-optic Kerr spectrometer (MOKS); (3) measure the dielectric tensor of thin-film and multilayer samples using our variable-angle magneto-optic ellipsometer (VAMOE); (4) measure the hysteresis loop, coercivity, remanent magnetization, saturation magnetization, and anisotropy energy constant for thin film magnetic media using vibrating sample magnetometry; (5) observe small magnetic domains and investigate their interaction with defects using magnetic force microscopy; (6) perform static read/write/erase experiments on thin-film magneto-optic media using our static test station; (7) integrate the existing models of magnetization, magneto-optic effects, coercivity, and anisotropy in an interactive and user-friendly environment, and analyze the characterization data obtained in the various experiments, using this modeling package; (8) measure focusing- and tracking-error signals on a static testbed, determine the 'feedthrough' for various focusing schemes, investigate the effects of polarization and birefringence, and compare the results with diffraction-based calculations; and (9) measure the birefringence of optical disk substrates using two variable angle ellipsometers.

Back focal plane microscopic ellipsometer with internal reflection geometry

NASA Astrophysics Data System (ADS)

Otsuki, Soichi; Murase, Norio; Kano, Hiroshi

2013-05-01

A back focal plane (BFP) ellipsometer is presented to measure a thin film on a cover glass using an oil-immersion high-numerical-aperture objective lens. The internal reflection geometry lowers the pseudo Brewster angle (ϕB) to the range over which the light distribution is observed in BFP of the objective. A calculation based on Mueller matrix was developed to compute ellipsometric parameters from the intensity distribution on BFP. The center and radius of the partial reflection region below the critical angle were determined and used to define a polar coordinate on BFP. Harmonic components were computed from the intensities along the azimuth direction and transformed to ellipsometric parameters at multiple incident angles around ϕB. The refractive index and thickness of the film and the contributions of the objective effect were estimated at the same time by fitting.

Enhancement of Aviation Fuel Thermal Stability Characterization Through Application of Ellipsometry

NASA Technical Reports Server (NTRS)

Browne, Samuel Tucker; Wong, Hubert; Hinderer, Cameron Branch; Klettlinger, Jennifer

2012-01-01

ASTM D3241/Jet Fuel Thermal Oxidation Tester (JFTOT) procedure, the standard method for testing thermal stability of conventional aviation turbine fuels is inherently limited due to the subjectivity in the color standard for tube deposit rating. Quantitative assessment of the physical characteristics of oxidative fuel deposits provides a more powerful method for comparing the thermal oxidation stability characteristics of fuels, especially in a research setting. We propose employing a Spectroscopic Ellipsometer to determine the film thickness and profile of oxidative fuel deposits on JFTOT heater tubes. Using JP-8 aviation fuel and following a modified ASTM D3241 testing procedure, the capabilities of the Ellipsometer will be demonstrated by measuring oxidative fuel deposit profiles for a range of different deposit characteristics. The testing completed in this report was supported by the NASA Fundamental Aeronautics Subsonics Fixed Wing Project

Parallel detecting, spectroscopic ellipsometers/polarimeters

DOEpatents

Furtak, Thomas E.

2002-01-01

The parallel detecting spectroscopic ellipsometer/polarimeter sensor has no moving parts and operates in real-time for in-situ monitoring of the thin film surface properties of a sample within a processing chamber. It includes a multi-spectral source of radiation for producing a collimated beam of radiation directed towards the surface of the sample through a polarizer. The thus polarized collimated beam of radiation impacts and is reflected from the surface of the sample, thereby changing its polarization state due to the intrinsic material properties of the sample. The light reflected from the sample is separated into four separate polarized filtered beams, each having individual spectral intensities. Data about said four individual spectral intensities is collected within the processing chamber, and is transmitted into one or more spectrometers. The data of all four individual spectral intensities is then analyzed using transformation algorithms, in real-time.

Towards a direct measurement of vacuum magnetic birefringence: PVLAS achievements

NASA Astrophysics Data System (ADS)

Della Valle, F.; Di Domenico, G.; Gastaldi, U.; Milotti, E.; Pengo, R.; Ruoso, G.; Zavattini, G.

2010-11-01

Nonlinear effects in vacuum have been predicted but never observed yet directly. The PVLAS collaboration has long been working on an apparatus aimed at detecting such effects by measuring vacuum magnetic birefringence. Unfortunately the sensitivity has been affected by unaccounted noise and systematics since the beginning. A new small prototype ellipsometer has been designed and characterized at the Department of Physics of the University of Ferrara, Italy entirely mounted on a single seismically isolated optical bench. With a finesse F = 414,000 and a cavity length L = 0.5 m we have reached the sensitivity of ψ=2ṡ101/√{Hz} given the laser power at the output of the ellipsometer of P = 24 mW. This record result, very close to the predicted limit, demonstrates the feasibility of reaching such sensitivities, and opens the way to designing a dedicated apparatus for a first detection of vacuum magnetic birefringence.

X-ray resonant magnetic scattering ellipsometer

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

Xu, Z.; Randall, K.J.; Gluskin, E.

1996-09-01

It is very difficult to characterize the polarization of a synchrotron radiation source in the soft and/or intermediate x-ray energy region particularly from 1 to 2 keV. Conventional multilayer mirror or single-crystal polarimeters do not work over this energy region because their throughput (the reflectivities combined with the phase shift) becomes insignificant. In this paper, we present a new ellipsometer scheme that is able to fully characterize the polarization of synchrotron radiation sources in this energy region. It is based on the dichroic x-ray resonant ferromagnetic scattering that yields information on both the polarization of the x-ray and the materialmore » (element specific) dielectric-constant tensor [C.-C. Kao {ital et} {ital al}., Phys. Rev. B {bold 50}, 9599 (1994)] due to the interband ferromagnetic Kerr effect [B.R. Cooper, Phys. Rev. A {bold 139}, 1504 (1965)]. {copyright} {ital 1996 American Institute of Physics.}« less

Ellipsometry of anodic film growth

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

Smith, C.G.

1978-08-01

An automated computer interpretation of ellisometer measurements of anodic film growth was developed. Continuous mass and charge balances were used to utilize more fully the time dependence of the ellipsometer data and the current and potential measurements. A multiple-film model was used to characterize the growth of films which proceeds via a dissolution--precipitation mechanism; the model also applies to film growth by adsorption and nucleation mechanisms. The characteristic parameters for film growth describe homogeneous and heterogeneous crystallization rates, film porosities and degree of hydration, and the supersaturation of ionic species in the electrolyte. Additional descriptions which may be chosen aremore » patchwise film formation, nonstoichiometry of the anodic film, and statistical variations in the size and orientation of secondary crystals. Theories were developed to describe the optical effects of these processes. An automatic, self-compensating ellipsometer was used to study the growth in alkaline solution of anodic films on silver, cadmium, and zinc. Mass-transport conditions included stagnant electrolyte and forced convection in a flow channel. Multiple films were needed to characterize the optical properties of these films. Anodic films grew from an electrolyte supersatuated in the solution-phase dissolution product. The degree of supersaturation depended on transport conditions and had a major effect on the structure of the film. Anodic reaction rates were limited by the transport of charge carriers through a primary surface layer. The primary layers on silver, zinc, and cadmium all appeared to be nonstoichiometric, containing excess metal. Diffusion coefficients, transference numbers, and the free energy of adsorption of zinc oxide were derived from ellipsometer measurements. 97 figures, 13 tables, 198 references.« less

Experimental study of nanofluidics and phase transitions of normal and superfluid 4He

NASA Astrophysics Data System (ADS)

Velasco, Angel Enriques

This thesis addresses the experimental results of two different research topics. The first is the experimental work of pressure driven flows in the smallest, single nanotubes ever investigated. The nanotube boundary conditions and slip lengths from argon, nitrogen, water, and helium experiments were analyzed and compared to macroscopic boundary conditions. The second research topic discusses the work on ellipsometric and quartz microbalance measurements of the 2D superfluid phase diagram of 4He on alkali substrates. Ellipsometric results of sodium on HOPG provide the first evidence of the existence of the 2D critical point on an intermediate strength substrate. Pressure driven flows through single nanopores and microtubes were measured with a calibrated mass spectrometer with pressure drops up to 30 Atm. The nanopores were between 30 nm to 600 nm in diameter and etched in mica and PET membranes of several microns thickness. Microtubes several inches long of fused quartz and nickel material were tested with diameters between 1.8 micron and 25 micron. For 4He and argon gas we observed the flow transition between the free molecular and continuum regimes at 293 K and 77 K. No discrepancy between the macroscopic theory and the 30 nm nanopore data was found. Because of the exceptionally low viscosity of gaseous helium the laminar-turbulent transition could also be observed within these submicron channels. The small viscosity of 4He was too small to dampen inertial effects at a Reynolds number of 2000. In addition to single phase gas flows, our experimental technique also allows us to investigate flows in which the nano or micro scale pipe is either partially or completely filled with liquids. The position of the intrinsic liquid/vapor interface was important for understanding this type of flow. Strong evaporation and cooling at the liquid-vapor interface can lead to freezing for conventional fluids such as nitrogen and water, which in turn leads to complex intermittent flows. The second portion of this thesis presents the experimental results on the 2D superfluid phase diagram of helium on alkali metals. A simultaneous measurement of the total and superfluid film thickness were done with a combination of a photoelastic modulated ellipsometer and a quartz crystal microbalance. Sodium and lithium films were ablated onto the gold electrodes of a QCM at 4 K. The adsorption isotherms of 4He were controlled by increasing the chemical potential from vacuum to bulk coexistence. The behavior of helium films are dependent on the strength of the substrate potential. For strong potentials such as gold and graphite the initial layers solidify while for the weaker substrate cesium films do not grow. Lithium and sodium were predicted to be intermediate in strength and for a mobile, helium film to directly grow on its surface. In addition to the superfluid transition a liquid/vapor coexistence region was predicted to also exist directly on an intermediate strength substrate. Our simultaneous QCM and ellipsometer measurements showed no clear evidence for the coexistence of 2D liquid/vapor on sodium or lithium. The gold electrodes which supported the alkali films were suspected of being too rough. We then ablated sodium on atomically smooth HOPG and the ellipsometer measured a discontinuous step at 0.5 K implying a liquid/vapor coexistence which decreased in size until it disappeared at the critical temperature T≈0.7 K. This is the first experimental evidence of a 2D critical point on sodium. (Abstract shortened by UMI.).

Semiconductor technology program: Progress briefs

NASA Technical Reports Server (NTRS)

Galloway, K. F.; Scace, R. I.; Walters, E. J.

1981-01-01

Measurement technology for semiconductor materials, process control, and devices, is discussed. Silicon and silicon based devices are emphasized. Highlighted activities include semiinsulating GaAs characterization, an automatic scanning spectroscopic ellipsometer, linewidth measurement and coherence, bandgap narrowing effects in silicon, the evaluation of electrical linewidth uniformity, and arsenicomplanted profiles in silicon.

Development of a spectroscopic Mueller matrix imaging ellipsometer for nanostructure metrology

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

Chen, Xiuguo; Du, Weichao; Yuan, Kui

2016-05-15

In this paper, we describe the development of a spectroscopic Mueller matrix imaging ellipsometer (MMIE), which combines the great power of Mueller matrix ellipsometry with the high spatial resolution of optical microscopy. A dual rotating-compensator configuration is adopted to collect the full 4 × 4 imaging Mueller matrix in a single measurement. The light wavelengths are scanned in the range of 400–700 nm by a monochromator. The instrument has measurement accuracy and precision better than 0.01 for all the Mueller matrix elements in both the whole image and the whole spectral range. The instrument was then applied for the measurementmore » of nanostructures combined with an inverse diffraction problem solving technique. The experiment performed on a photoresist grating sample has demonstrated the great potential of MMIE for accurate grating reconstruction from spectral data collected by a single pixel of the camera and for efficient quantification of geometrical profile of the grating structure over a large area with pixel resolution. It is expected that MMIE will be a powerful tool for nanostructure metrology in future high-volume nanomanufacturing.« less

Acquisition of Infrared Variable Angle Spectroscopic Ellipsometer (IR-VASE)

DTIC Science & Technology

2016-04-22

External Advisory Board Meeting in Rio Piedras, PR. March 2016 Quiñonez B.*, Castilla D., Almodóvar J.; “ Polysaccharide -based polyelectrolyte...April 2016 Quiñonez B.*, Castilla D., Almodóvar J.; “ Polysaccharide -based polyelectrolyte multilayers: Physicochemical characterization and in...2016 Quiñonez B.*, Castilla D., Almodóvar J.; “ Polysaccharide -based polyelectrolyte multilayers: Physicochemical characterization and in vitro

Investigating the Electron-Phonon Coupling of Molecular Beam Epitaxy-Grown Hg1-x Cd x Se Semiconductor Alloys

NASA Astrophysics Data System (ADS)

Peiris, F. C.; Lewis, M. V.; Brill, G.; Doyle, Kevin; Myers, T. H.

2018-03-01

Using spectroscopic ellipsometry, the temperature-dependence of the dielectric functions of a series of Hg1-x Cd x Se thin films deposited on both ZnTe/Si(112) and GaSb(112) substrates were investigated. Initially, for each sample, room-temperature ellipsometric spectra were obtained from 35 meV to 6 eV using two different ellipsometers. Subsequently, ellipsometry spectra were obtained from 10 K to 300 K by incorporating a cryostat to the ellipsometer. Using a standard inversion technique, the spectroscopic ellipsometric data were modeled in order to obtain the temperature-dependent dielectric functions of each of the Hg1-x Cd x Se thin films. The results indicate that the E 1 critical point blue-shifts as a function of Cd-alloy concentration. The temperature-dependence of E 1 was fitted to a Bose-Einstein occupation distribution function, which consequently allowed us to determine the electron-phonon coupling of Hg1-x Cd x Se alloys. From the fitting results, we obtain a value of 17 ± 2 meV for the strength of the electron-phonon coupling for Hg1-x Cd x Se alloy system, which compares nominally with the binary systems, such as CdSe and CdTe, which have values around 38 meV and 16 meV, respectively. This implies that the addition of Hg into the CdSe binary system does not significantly alter its electron-phonon coupling strength. Raman spectroscopy measurements performed on all the samples show the HgSe-like transverse optic (TO) and longitudinal optic (LO) phonons (˜ 130 cm-1 and ˜ 160 cm-1, respectively) for all the samples. While there is a slight red-shift of the HgSe-like TO peak as a function of the Cd-concentration, HgSe-like LO peak does not significantly change with the alloy concentration.

Measurement of refractive indices of tunicates' tunics: light reflection of the transparent integuments in an ascidian Rhopalaea sp. and a salp Thetys vagina.

PubMed

Kakiuchida, Hiroshi; Sakai, Daisuke; Nishikawa, Jun; Hirose, Euichi

2017-01-01

Tunic is a cellulosic, integumentary matrix found in tunicates (Subphylum Tunicata or Urochordata). The tunics of some ascidian species and pelagic tunicates, such as salps, are nearly transparent, which is useful in predator avoidance. Transparent materials can be detected visually using light reflected from their surfaces, with the different refractive indices between two media, i.e., tunic and seawater, being the measure of reflectance. A larger difference in refractive indices thus provides a larger measure of reflectance. We measured the refractive indices of the transparent tunic of Thetys vagina (salp: Thaliacea) and Rhopalae a sp. (ascidian: Ascidiacea) using an Abbe refractometer and an ellipsometer to estimate the light reflection at the tunic surface and evaluate the anti-reflection effect of the nipple array structure on the tunic surface of T. vagina . At D-line light (λ = 589 nm), the refractive indices of the tunics were 0.002-0.004 greater than seawater in the measurements by Abbe refractometer, and 0.02-0.03 greater than seawater in the measurements by ellipsometer. The refractive indices of tunics were slightly higher than that of seawater. According to the simulation of light reflection based on rigorous coupled wave analysis (RCWA), light at a large angle of incidence will be completely reflected from a surface when its refractive indices are smaller than seawater. Therefore, the refractive index of integument is important for enabling transparent organisms to remain invisible in the water column. In order to minimize reflectance, the refractive index should be similar to, but never smaller than, that of the surrounding seawater. The simulation also indicated that the presence or absence of a nipple array does not cause significant difference in reflectance on the surface. The nipple array on the tunic of the diurnal salp may have another function, such as bubble repellence, other than anti-reflection.

An integrated platform for biomolecule interaction analysis

NASA Astrophysics Data System (ADS)

Jan, Chia-Ming; Tsai, Pei-I.; Chou, Shin-Ting; Lee, Shu-Sheng; Lee, Chih-Kung

2013-02-01

We developed a new metrology platform which can detect real-time changes in both a phase-interrogation mode and intensity mode of a SPR (surface plasmon resonance). We integrated a SPR and ellipsometer to a biosensor chip platform to create a new biomolecular interaction measurement mechanism. We adopted a conductive ITO (indium-tinoxide) film to the bio-sensor platform chip to expand the dynamic range and improve measurement accuracy. The thickness of the conductive film and the suitable voltage constants were found to enhance performance. A circularly polarized ellipsometry configuration was incorporated into the newly developed platform to measure the label-free interactions of recombinant human C-reactive protein (CRP) with immobilized biomolecule target monoclonal human CRP antibody at various concentrations. CRP was chosen as it is a cardiovascular risk biomarker and is an acute phase reactant as well as a specific prognostic indicator for inflammation. We found that the sensitivity of a phaseinterrogation SPR is predominantly dependent on the optimization of the sample incidence angle. The effect of the ITO layer effective index under DC and AC effects as well as an optimal modulation were experimentally performed and discussed. Our experimental results showed that the modulated dynamic range for phase detection was 10E-2 RIU based on a current effect and 10E-4 RIU based on a potential effect of which a 0.55 (°/RIU) measurement was found by angular-interrogation. The performance of our newly developed metrology platform was characterized to have a higher sensitivity and less dynamic range when compared to a traditional full-field measurement system.

Instrumentation of the variable-angle magneto-optic ellipsometer and its application to M-O media and other non-magnetic films

NASA Technical Reports Server (NTRS)

Zhou, Andy F.; Erwin, J. Kevin; Mansuripur, M.

1992-01-01

A new and comprehensive dielectric tensor characterization instrument is presented for characterization of magneto-optical recording media and non-magnetic thin films. Random and systematic errors of the system are studied. A series of TbFe, TbFeCo, and Co/Pt samples with different composition and thicknesses are characterized for their optical and magneto-optical properties. The optical properties of several non-magnetic films are also measured.

Swedish Defence Research Abstracts 1980/81-3 (Froe Forsvars Forsknings Referat 1980/81-3).

DTIC Science & Technology

1981-11-01

computes the refractive index or the thickness of thin mono- or multi -layer films. The program is written in Fortran and is adapted to the ellipsometer at...Unmnnounced EtN8PECT: Justlflotl Distribution/ Availability Codes Avail and/or Dist Special 2 Index to FRO 80/81-3 A PROTECTION - ATOMIC Al The nuclear...aberrations in PHA-stimulated human lymphocytes in the GI stage (in English) B PROTECTION - BIOLOGICAL BI Threat scenario (119) Epidemiological aspects

Ellipsometric surface analysis of wear tracks produced by different lubricants

NASA Technical Reports Server (NTRS)

Lauer, J. L.; Marxer, N.; Jones, W. R., Jr.

1985-01-01

A scanning ellipsometer with high spatial resolution was used to analyze wear tracks generated on M-50 surfaces operated in several lubricant formulations. These formulations included a pure ester base stock of trimethyol propane triheptanoate with additives of either benzotriazole (BTZ), dioctyldiphenylamine (DODPA), or tricresylphosphate (TCP). Results indicated that BTZ and TCP produced patchy oxide surface films consisting mainly of Fe304. DOPDA produced a much more uniform oxide film. These findings may explain the tendency of lubricant formulations containing TCP to scuff more readily than those containing only antioxidants.

Ellipsometric surface analysis of wear tracks produced by different lubricants

NASA Technical Reports Server (NTRS)

Lauer, J. L.; Marxer, N.; Jones, W. R., Jr.

1985-01-01

Ellipsometric analyses of wear tracks in berings of M-50 steel were carried out after operation under severe conditions with different lubricant additives. The base lubricant was a synthetic ester. It was found that the surface and wear additives benzotirazole and tricresylyphosphate produced very patchy oxide layers. Dioctyldiphenylamine, a common antioxidant, on the other hand produced smoother films. The analyses were performed with a specially designed and constructed ellipsometer of very high (20 micron) spatial resolution. The results are consistent with data obtained by Auger electron spectroscopy.

High Order Modulation Protograph Codes

NASA Technical Reports Server (NTRS)

Nguyen, Thuy V. (Inventor); Nosratinia, Aria (Inventor); Divsalar, Dariush (Inventor)

2014-01-01

Digital communication coding methods for designing protograph-based bit-interleaved code modulation that is general and applies to any modulation. The general coding framework can support not only multiple rates but also adaptive modulation. The method is a two stage lifting approach. In the first stage, an original protograph is lifted to a slightly larger intermediate protograph. The intermediate protograph is then lifted via a circulant matrix to the expected codeword length to form a protograph-based low-density parity-check code.

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

Jellison, G. E.; Aytug, T.; Lupini, A. R.

Nanostructured glass films, which are fabricated using spinodally phase-separated low-alkali glasses, have several interesting and useful characteristics, including being robust, non-wetting and antireflective. Spectroscopic ellipsometry measurements have been performed on one such film and its optical properties were analyzed using a 5-layer structural model of the near-surface region. Since the glass and the film are transparent over the spectral region of the measurement, the Sellmeier model is used to parameterize the dispersion in the refractive index. To simulate the variation of the optical properties of the film over the spot size of the ellipsometer (~ 3 × 5 mm), themore » Sellmeier amplitude is convoluted using a Gaussian distribution. The transition layers between the ambient and the film and between the film and the substrate are modeled as graded layers, where the refractive index varies as a function of depth. These layers are modeled using a two-component Bruggeman effective medium approximation where the two components are the layer above and the layer below. Lastly, the fraction is continuous through the transition layer and is modelled using the incomplete beta function.« less

The influence of voltage applied between the electrodes on optical and morphological properties of the InGaN thin films grown by thermionic vacuum arc.

PubMed

Özen, Soner; Şenay, Volkan; Pat, Suat; Korkmaz, Şadan

2016-01-01

The aim of this research is to investigate the optical and morphological properties of the InGaN thin films deposited onto amorphous glass substrates in two separate experiments with two different voltages applied between the electrodes, i.e. 500 and 600 V by means of the thermionic vacuum arc technique. This technique is original for thin film deposition and it enables thin film production in a very short period of time. The optical and morphological properties of the films were investigated by using field emission scanning electron microscope, atomic force microscope, spectroscopic ellipsometer, reflectometer, spectrophotometer, and optical tensiometer. Optical properties were also supported by empirical relations. The deposition rates were calculated as 3 and 3.3 nm/sec for 500 and 600 V, respectively. The increase in the voltage also increased the refractive index, grain size, root mean square roughness and surface free energy. According to the results of the wetting experiments, InGaN samples were low-wettable, also known as hydrophobic. © Wiley Periodicals, Inc.

Single-tone and two-tone AM-FM spectral calculations for tunable diode laser absorption spectroscopy

NASA Technical Reports Server (NTRS)

Chou, Nee-Yin; Sachse, Glen W.

1987-01-01

A generalized theory for optical heterodyne spectroscopy with phase modulated laser radiation is used which allows the calculation of signal line shapes for frequency modulation spectroscopy of Lorentzian gas absorption lines. In particular, synthetic spectral line shapes for both single-tone and two-tone modulation of lead-salt diode lasers are presented in which the contributions from both amplitude and frequency modulations are included.

Generalization of the Förster resonance energy transfer theory for quantum mechanical modulation of the donor-acceptor coupling

NASA Astrophysics Data System (ADS)

Jang, Seogjoo

2007-11-01

The Förster resonance energy transfer theory is generalized for inelastic situations with quantum mechanical modulation of the donor-acceptor coupling. Under the assumption that the modulations are independent of the electronic excitation of the donor and the acceptor, a general rate expression is derived, which involves two dimensional frequency-domain convolution of the donor emission line shape, the acceptor absorption line shape, and the spectral density of the modulation of the donor-acceptor coupling. For two models of modulation, detailed rate expressions are derived. The first model is the fluctuation of the donor-acceptor distance, approximated as a quantum harmonic oscillator coupled to a bath of other quantum harmonic oscillators. The distance fluctuation results in additional terms in the rate, which in the small fluctuation limit depend on the inverse eighth power of the donor-acceptor distance. The second model is the fluctuation of the torsional angle between the two transition dipoles, which is modeled as a quantum harmonic oscillator coupled to a bath of quantum harmonic oscillators and causes sinusoidal modulation of the donor-acceptor coupling. The rate expression has new elastic and inelastic terms, depending sensitively on the value of the minimum energy torsional angle. Experimental implications of the present theory and some of the open theoretical issues are discussed.

Inflatable nested toroid structure

NASA Technical Reports Server (NTRS)

Johnson, Christopher J. (Inventor); Raboin, Jasen L. (Inventor); Spexarth, Gary R. (Inventor)

2011-01-01

An inflatable structure comprises at least two generally toroidal, inflatable modules. When in a deployed mode, the first, inner module has a major diameter less than that of a second, outer module and is positioned within the inner circumference of the outer module such that the first module is nested circumferentially alongside the second module. The inflatable structure, in a non-deployed, non-inflated mode, is of compact configuration and adapted to be transported to a site of deployment. When deployed, the inflatable structure is of substantially increased interior volume. In one embodiment, access between the interior of the first module and the second module is provided by at least one port or structural pass-through. In another embodiment, the inflatable structure includes at least one additional generally toroidal module external of and circumferentially surrounding the second module.

Using a Thematic Laboratory-Centered Curriculum to Teach General Chemistry

ERIC Educational Resources Information Center

Hopkins, Todd A.; Samide, Michael

2013-01-01

This article describes an approach to general chemistry that involves teaching chemical concepts in the context of two thematic laboratory modules: environmental remediation and the fate of pharmaceuticals in the environment. These modules were designed based on active-learning pedagogies and involve multiple-week projects that dictate what…

Spectroscopic ellipsometry in vacuum ultraviolet spectral area

NASA Astrophysics Data System (ADS)

Fuchs, Detlef

An ellipsometer is developed and built, which allows the direct spectroscopic evaluation of dielectric function of solid bodies in the energy area 5 to 35 eV. A linear polarized synchrotron radiation was used as light source. The Stokes parameters and the Mueller matrices were used for the mathematical modeling, which take into account the properties of the synchrotron light and the analyzer, which depend on the wavelength. The crystals of the semiconductor bindings GaAs, GaP, InP and ZnS were examined. Ellipsometric measurements and reflection spectra show a displacement of spectral structures towards lower photon energies after the storage.

Ellipsometric Analysis of Contaminant Layer on Optical Witness Samples from MISSE

NASA Technical Reports Server (NTRS)

Norwood, Joseph K.

2007-01-01

Several optical witness samples included in the Materials for International Space Station Experiment (MISSE) trays have been analyzed with a variable angle spectroscopic ellipsometer or VASE. Witness samples of gold or platinum mirrors are extremely useful as collectors of space-borne contamination, due to the relative inertness of these noble metals in the atomic oxygen-rich environment of LEO. Highly accurate thickness measurements, typically at the sub-nanometer scale, may be achieved with this method, which uses polarized light in a spectral range of 300 to 1300 nanometers at several angles of incidence to the sample surface.

Optical properties of a nanostructured glass-based film using spectroscopic ellipsometry

DOE PAGES

Jellison, G. E.; Aytug, T.; Lupini, A. R.; ...

2015-12-22

Nanostructured glass films, which are fabricated using spinodally phase-separated low-alkali glasses, have several interesting and useful characteristics, including being robust, non-wetting and antireflective. Spectroscopic ellipsometry measurements have been performed on one such film and its optical properties were analyzed using a 5-layer structural model of the near-surface region. Since the glass and the film are transparent over the spectral region of the measurement, the Sellmeier model is used to parameterize the dispersion in the refractive index. To simulate the variation of the optical properties of the film over the spot size of the ellipsometer (~ 3 × 5 mm), themore » Sellmeier amplitude is convoluted using a Gaussian distribution. The transition layers between the ambient and the film and between the film and the substrate are modeled as graded layers, where the refractive index varies as a function of depth. These layers are modeled using a two-component Bruggeman effective medium approximation where the two components are the layer above and the layer below. Lastly, the fraction is continuous through the transition layer and is modelled using the incomplete beta function.« less

Microscopic image processing systems for measuring nonuniform film thickness profiles

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

Liu, A.H.; Plawsky, J.L.; DasGupta, S.

1994-01-01

In very thin liquid films. transport processes are controlled by the temperature and the interfacial intermolecular force field which is a function of the film thickness profile and interfacial properties. The film thickness profile and interfacial properties can be measured most efficiently using a microscopic image processing system. IPS, to record the intensity pattern of the reflected light from the film. There are two types of IPS: an image analyzing interferometer (IAI) and/or an image scanning ellipsometer (ISE). The ISE is a novel technique to measure the two dimensional thickness profile of a nonuniform, thin film, from 1 nm upmore » to several {mu}m, in a steady state as well as in a transient state. It is a full field imaging technique which can study every point on the surface simultaneously with high spatial resolution and thickness sensitivity, i.e., it can measure and map the 2-D film thickness profile. Using the ISE, the transient thickness profile of a draining thin liquid film was measured and modeled. The interfacial conditions were determined in situ by measuring the Hamaker constant. The ISE and IAI systems are compared.« less

EUV polarimetry for thin film and surface characterization and EUV phase retarder reflector development.

PubMed

Gaballah, A E H; Nicolosi, P; Ahmed, Nadeem; Jimenez, K; Pettinari, G; Gerardino, A; Zuppella, P

2018-01-01

The knowledge and the manipulation of light polarization state in the vacuum ultraviolet and extreme ultraviolet (EUV) spectral regions play a crucial role from materials science analysis to optical component improvements. In this paper, we present an EUV spectroscopic ellipsometer facility for polarimetry in the 90-160 nm spectral range. A single layer aluminum mirror to be used as a quarter wave retarder has been fully characterized by deriving the optical and structural properties from the amplitude component and phase difference δ measurements. The system can be suitable to investigate the properties of thin films and optical coatings and optics in the EUV region.

Solid-state dewetting of thin Au films studied with real-time, in situ spectroscopic ellipsometry

NASA Astrophysics Data System (ADS)

Magnozzi, M.; Bisio, F.; Canepa, M.

2017-11-01

We report the design and testing of a small, high vacuum chamber that allows real-time, in situ spectroscopic ellipsometry (SE) measurements; the chamber was designed to be easily inserted within the arms of a commercial ellipsometer. As a test application, we investigated the temperature-induced solid-state dewetting of thin (20 to 8 nm) Au layers on Si wafers. In situ SE measurements acquired in real time during the heating of the samples reveal features that can be related to the birth of a localized surface plasmon resonance (LSPR), and demonstrate the presence of a temperature threshold for the solid-state dewetting.

Electrostatic self-assembly of polyions on charged substrates

NASA Astrophysics Data System (ADS)

Campbell, A.; Adams, W. W.; Bunning, T. J.; Visser, D.; Bliznyuk, V. N.; Tsukruk, V. V.

1997-03-01

The kinetics of formation of self-assembled monolayers is studied for polystyrene sulfonate(PSS) adsorbed on oppositely charged surfaces of amine terminated self-assembled monolayers(SAM) and polyallylamine(PAA). During the early stages of deposition in both cases, an inhomogeneous deposition is noted as measured by atomic force and friction force microscopy. Island formation of unperturbed PSS coils on defect sites is observed during the initial stage of deposition. Longer deposition times result in an equilibration of the polymer layers into highly flattened macromolecular chains. AFM and FFM measurements are combined with ellipsometer and X-ray reflectivity results to quantitate the layer thicknesses and roughness with time.

Performance Analysis and Design Synthesis (PADS) computer program. Volume 3: User manual

NASA Technical Reports Server (NTRS)

1972-01-01

The two-fold purpose of the Performance Analysis and Design Synthesis (PADS) computer program is discussed. The program can size launch vehicles in conjunction with calculus-of-variations optimal trajectories and can also be used as a general purpose branched trajectory optimization program. For trajectory optimization alone or with sizing, PADS has two trajectory modules. The first trajectory module uses the method of steepest descent. The second module uses the method of quasi-linearization, which requires a starting solution from the first trajectory module.

MEG evidence that the central auditory system simultaneously encodes multiple temporal cues.

PubMed

Simpson, Michael I G; Barnes, Gareth R; Johnson, Sam R; Hillebrand, Arjan; Singh, Krish D; Green, Gary G R

2009-09-01

Speech contains complex amplitude modulations that have envelopes with multiple temporal cues. The processing of these complex envelopes is not well explained by the classical models of amplitude modulation processing. This may be because the evidence for the models typically comes from the use of simple sinusoidal amplitude modulations. In this study we used magnetoencephalography (MEG) to generate source space current estimates of the steady-state responses to simple one-component amplitude modulations and to a two-component amplitude modulation. A two-component modulation introduces the simplest form of modulation complexity into the waveform; the summation of the two-modulation rates introduces a beat-like modulation at the difference frequency between the two modulation rates. We compared the cortical representations of responses to the one-component and two-component modulations. In particular, we show that the temporal complexity in the two-component amplitude modulation stimuli was preserved at the cortical level. The method of stimulus normalization that we used also allows us to interpret these results as evidence that the important feature in sound modulations is the relative depth of one modulation rate with respect to another, rather than the absolute carrier-to-sideband modulation depth. More generally, this may be interpreted as evidence that modulation detection accurately preserves a representation of the modulation envelope. This is an important observation with respect to models of modulation processing, as it suggests that models may need a dynamic processing step to effectively model non-stationary stimuli. We suggest that the classic modulation filterbank model needs to be modified to take these findings into account.

Improvements in world-wide intercomparison of PV module calibration

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

Salis, E.; Pavanello, D.; Field, M.

The calibration of the electrical performance of seven photovoltaic (PV) modules was compared between four reference laboratories on three continents. The devices included two samples in standard and two in high-efficiency crystalline silicon technology, two CI(G)S and one CdTe module. The reference value for each PV module parameter was calculated from the average of the results of all four laboratories, weighted by the respective measurement uncertainties. All single results were then analysed with respect to this reference value using the E n number approach. For the four modules in crystalline silicon technology, the results agreed in general within +/-0.5%, withmore » all values within +/-1% and all E n numbers well within [-1, 1], indicating further scope for reducing quoted measurement uncertainty. Regarding the three thin-film modules, deviations were on average roughly twice as large, i.e. in general from +/-1% to +/-2%. A number of inconsistent results were observable, although within the 5% that can be statistically expected on the basis of the E n number approach. Most inconsistencies can be traced to the preconditioning procedure of one participant, although contribution of other factors cannot be ruled out. After removing these obvious inconsistent results, only two real outliers remained, representing less than 2% of the total number of measurands. The results presented show improved agreement for the calibration of PV modules with respect to previous international exercises. For thin-film PV modules, the preconditioning of the devices prior to calibration measurements is the most critical factor for obtaining consistent results, while the measurement processes seem consistent and repeatable.« less

Improvements in world-wide intercomparison of PV module calibration

DOE PAGES

Salis, E.; Pavanello, D.; Field, M.; ...

2017-09-14

The calibration of the electrical performance of seven photovoltaic (PV) modules was compared between four reference laboratories on three continents. The devices included two samples in standard and two in high-efficiency crystalline silicon technology, two CI(G)S and one CdTe module. The reference value for each PV module parameter was calculated from the average of the results of all four laboratories, weighted by the respective measurement uncertainties. All single results were then analysed with respect to this reference value using the E n number approach. For the four modules in crystalline silicon technology, the results agreed in general within +/-0.5%, withmore » all values within +/-1% and all E n numbers well within [-1, 1], indicating further scope for reducing quoted measurement uncertainty. Regarding the three thin-film modules, deviations were on average roughly twice as large, i.e. in general from +/-1% to +/-2%. A number of inconsistent results were observable, although within the 5% that can be statistically expected on the basis of the E n number approach. Most inconsistencies can be traced to the preconditioning procedure of one participant, although contribution of other factors cannot be ruled out. After removing these obvious inconsistent results, only two real outliers remained, representing less than 2% of the total number of measurands. The results presented show improved agreement for the calibration of PV modules with respect to previous international exercises. For thin-film PV modules, the preconditioning of the devices prior to calibration measurements is the most critical factor for obtaining consistent results, while the measurement processes seem consistent and repeatable.« less

Coupled incompressible Smoothed Particle Hydrodynamics model for continuum-based modelling sediment transport

NASA Astrophysics Data System (ADS)

Pahar, Gourabananda; Dhar, Anirban

2017-04-01

A coupled solenoidal Incompressible Smoothed Particle Hydrodynamics (ISPH) model is presented for simulation of sediment displacement in erodible bed. The coupled framework consists of two separate incompressible modules: (a) granular module, (b) fluid module. The granular module considers a friction based rheology model to calculate deviatoric stress components from pressure. The module is validated for Bagnold flow profile and two standardized test cases of sediment avalanching. The fluid module resolves fluid flow inside and outside porous domain. An interaction force pair containing fluid pressure, viscous term and drag force acts as a bridge between two different flow modules. The coupled model is validated against three dambreak flow cases with different initial conditions of movable bed. The simulated results are in good agreement with experimental data. A demonstrative case considering effect of granular column failure under full/partial submergence highlights the capability of the coupled model for application in generalized scenario.

Quantum model for electro-optical amplitude modulation.

PubMed

Capmany, José; Fernández-Pousa, Carlos R

2010-11-22

We present a quantum model for electro-optic amplitude modulation, which is built upon quantum models of the main photonic components that constitute the modulator, that is, the guided-wave beamsplitter and the electro-optic phase modulator and accounts for all the different available modulator structures. General models are developed both for single and dual drive configurations and specific results are obtained for the most common configurations currently employed. Finally, the operation with two-photon input for the control of phase-modulated photons and the important topic of multicarrier modulation are also addressed.

Polarization modeling and predictions for Daniel K. Inouye Solar Telescope part 1: telescope and example instrument configurations

NASA Astrophysics Data System (ADS)

Harrington, David M.; Sueoka, Stacey R.

2017-01-01

We outline polarization performance calculations and predictions for the Daniel K. Inouye Solar Telescope (DKIST) optics and show Mueller matrices for two of the first light instruments. Telescope polarization is due to polarization-dependent mirror reflectivity and rotations between groups of mirrors as the telescope moves in altitude and azimuth. The Zemax optical modeling software has polarization ray-trace capabilities and predicts system performance given a coating prescription. We develop a model coating formula that approximates measured witness sample polarization properties. Estimates show the DKIST telescope Mueller matrix as functions of wavelength, azimuth, elevation, and field angle for the cryogenic near infra-red spectro-polarimeter (CryoNIRSP) and visible spectro-polarimeter. Footprint variation is substantial and shows vignetted field points will have strong polarization effects. We estimate 2% variation of some Mueller matrix elements over the 5-arc min CryoNIRSP field. We validate the Zemax model by showing limiting cases for flat mirrors in collimated and powered designs that compare well with theoretical approximations and are testable with lab ellipsometers.

Optical and Scratch Resistant Properties of Diamondlike Carbon Films Deposited with Single and Dual Ion Beams

NASA Technical Reports Server (NTRS)

Kussmaul, Michael T.; Bogdanski, Michael S.; Banks, Bruce A.; Mirtich, Michael J.

1993-01-01

Amorphous diamond-like carbon (DLC) films were deposited using both single and dual ion beam techniques utilizing filament and hollow cathode ion sources. Continuous DLC films up to 3000 A thick were deposited on fused quartz plates. Ion beam process parameters were varied in an effort to create hard, clear films. Total DLC film absorption over visible wavelengths was obtained using a Perkin-Elmer spectrophotometer. An ellipsometer, with an Ar-He laser (wavelength 6328 A) was used to determine index of refraction for the DLC films. Scratch resistance, frictional, and adherence properties were determined for select films. Applications for these films range from military to the ophthalmic industries.

Optical and scratch resistant properties of diamondlike carbon films deposited with single and dual ion beams

NASA Technical Reports Server (NTRS)

Kussmaul, Michael T.; Bogdanski, Michael S.; Banks, Bruce A.; Mirtich, Michael J.

1993-01-01

Amorphous diamondlike carbon (DLC) films were deposited using both single and dual ion beam techniques utilizing filament and hollow cathode ion sources. Continuous DLC films up to 3000 A thick were deposited on fused quartz plates. Ion beam process parameters were varied in an effort to create hard, clear films. Total DLC film absorption over visible wavelengths was obtained using a Perkin-Elmer spectrophotometer. An ellipsometer, with an Ar-He laser (wavelength 6328 A) was used to determine index of refraction for the DLC films. Scratch resistance and frictional and adherence properties were determined for select films. Applications for these films range from military to the ophthalmic industries.

Optical polarimetry: Instrumentation and applications; Proceedings of the Seminar, San Diego, Calif., August 23, 24, 1977

NASA Technical Reports Server (NTRS)

Azzam, R. M. A. (Editor); Coffeen, D. L.

1977-01-01

Instrumentation used in optical polarimetry is discussed with reference to high-resolution spectropolarimetry, an orbiter cloud photopolarimeter, X-ray polarimeters, and the design of a self-nulling ellipsometer. Consideration is given to surface and thin-film ellipsometry noting studies of electrochemical surface layers, surface anisotropy, polish layers on infrared window materials, and anodic films. Papers on biological, chemical, and physical polarimetry are presented including birefringence in biological materials, vibrational optical activity, and the optical determination of the thermodynamic phase diagram of a metamagnet. Remote sensing is discussed in terms of polarization imagery, the optical polarimetry of particulate surfaces, and techniques and applications of elliptical polarimetry in astronomy and atmospheric studies.

Measurements of vacuum magnetic birefringence using permanent dipole magnets: the PVLAS experiment

NASA Astrophysics Data System (ADS)

Della Valle, F.; Gastaldi, U.; Messineo, G.; Milotti, E.; Pengo, R.; Piemontese, L.; Ruoso, G.; Zavattini, G.

2013-05-01

The PVLAS collaboration is presently assembling a new apparatus (at the INFN section of Ferrara, Italy) to detect vacuum magnetic birefringence (VMB). VMB is related to the structure of the quantum electrodynamics (QED) vacuum and is predicted by the Euler-Heisenberg-Weisskopf effective Lagrangian. It can be detected by measuring the ellipticity acquired by a linearly polarized light beam propagating through a strong magnetic field. Using the very same optical technique it is also possible to search for hypothetical low-mass particles interacting with two photons, such as axion-like (ALP) or millicharged particles. Here we report the results of a scaled-down test setup and describe the new PVLAS apparatus. This latter is in construction and is based on a high-sensitivity ellipsometer with a high-finesse Fabry-Perot cavity (>4 × 105) and two 0.8 m long 2.5 T rotating permanent dipole magnets. Measurements with the test setup have improved, by a factor 2, the previous upper bound on the parameter Ae, which determines the strength of the nonlinear terms in the QED Lagrangian: A(PVLAS)e < 3.3 × 10-21 T-2 at 95% c.l. Furthermore, new laboratory limits have been put on the inverse coupling constant of ALPs to two photons and confirmation of previous limits on the fractional charge of millicharged particles is given.

On staggered indecomposable Virasoro modules

NASA Astrophysics Data System (ADS)

Kytölä, Kalle; Ridout, David

2009-12-01

In this article, certain indecomposable Virasoro modules are studied. Specifically, the Virasoro mode L0 is assumed to be nondiagonalizable, possessing Jordan blocks of rank 2. Moreover, the module is further assumed to have a highest weight submodule, the "left module," and that the quotient by this submodule yields another highest weight module, the "right module." Such modules, which have been called staggered, have appeared repeatedly in the logarithmic conformal field theory literature, but their theory has not been explored in full generality. Here, such a theory is developed for the Virasoro algebra using rather elementary techniques. The focus centers on two different but related questions typically encountered in practical studies: How can one identify a given staggered module, and how can one demonstrate the existence of a proposed staggered module. Given just the values of the highest weights of the left and right modules, themselves subject to simple necessary conditions, invariants are defined which together with the knowledge of the left and right modules uniquely identify a staggered module. The possible values of these invariants form a vector space of dimension 0, 1, or 2, and the structures of the left and right modules limit the isomorphism classes of the corresponding staggered modules to an affine subspace (possibly empty). The number of invariants and affine restrictions is purely determined by the structures of the left and right modules. Moreover, in order to facilitate applications, the expressions for the invariants and restrictions are given by formulas as explicit as possible (they generally rely on expressions for Virasoro singular vectors). Finally, the text is liberally peppered throughout with examples illustrating the general concepts. These have been carefully chosen for their physical relevance or for the novel features they exhibit.

Block 4 solar cell module design and test specification for residential applications

NASA Technical Reports Server (NTRS)

1978-01-01

Near-term design, qualification and acceptance requirements are provided for terrestrial solar cell modules suitable for incorporation in photovoltaic power sources (2 kW to 10 kW) applied to single family residential installations. Requirement levels and recommended design limits for selected performance criteria are specified for modules intended principally for rooftop installations. Modules satisfying the requirements of this specification fall into one of two categories, residential panel or residential shingle, both meeting general performance requirements plus additional category peculiar constraints.

Generalized stochastic resonance for a fractional harmonic oscillator with bias-signal-modulated trichotomous noise

NASA Astrophysics Data System (ADS)

Lin, Lifeng; Wang, Huiqi; Huang, Xipei; Wen, Yongxian

2018-03-01

For a fractional linear oscillator subjected to both parametric excitation of trichotomous noise and external excitation of bias-signal-modulated trichotomous noise, the generalized stochastic resonance (GSR) phenomena are investigated in this paper in case the noises are cross-correlative. First, the generalized Shapiro-Loginov formula and generalized fractional Shapiro-Loginov formula are derived. Then, by using the generalized (fractional) Shapiro-Loginov formula and the Laplace transformation technique, the exact expression of the first-order moment of the system’s steady response is obtained. The numerical results show that the evolution of the output amplitude amplification is nonmonotonic with the frequency of periodic signal, the noise parameters, and the fractional order. The GSR phenomena, including single-peak GSR, double-peak GSR and triple-peak GSR, are observed in this system. In addition, the interplay of the multiplicative trichotomous noise, bias-signal-modulated trichotomous noise and memory can induce and diversify the stochastic multi-resonance (SMR) phenomena, and the two kinds of trichotomous noises play opposite roles on the GSR.

Beginning English: An Instructional Guide for ESL Teachers.

ERIC Educational Resources Information Center

Brower, Lynne

An instructional guide for English as a Second Language (ESL) teachers is presented in this volume. The 18-week program contains the following modules, each of which includes sections on civics and structure: human relations; general information; housing; consumer education (money, banking, and shopping modules); occupations; health (two modules…

Performance Analysis and Design Synthesis (PADS) computer program. Volume 2: Program description, part 1

NASA Technical Reports Server (NTRS)

1972-01-01

The Performance Analysis and Design Synthesis (PADS) computer program has a two-fold purpose. It can size launch vehicles in conjunction with calculus-of-variations optimal trajectories and can also be used as a general-purpose branched trajectory optimization program. In the former use, it has the Space Shuttle Synthesis Program as well as a simplified stage weight module for optimally sizing manned recoverable launch vehicles. For trajectory optimization alone or with sizing, PADS has two trajectory modules. The first trajectory module uses the method of steepest descent; the second employs the method of quasilinearization, which requires a starting solution from the first trajectory module. For Volume 1 see N73-13199.

Singular observation of the polarization-conversion effect for a gammadion-shaped metasurface

PubMed Central

Lin, Chu-En; Yen, Ta-Jen; Yu, Chih-Jen; Hsieh, Cheng-Min; Lee, Min-Han; Chen, Chii-Chang; Chang, Cheng-Wei

2016-01-01

In this article, the polarization-conversion effects of a gammadion-shaped metasurface in transmission and reflection modes are discussed. In our experiment, the polarization-conversion effect of a gammadion-shaped metasurface is investigated because of the contribution of the phase and amplitude anisotropies. According to our experimental and simulated results, the polarization property of the first-order transmitted diffraction is dominated by linear anisotropy and has weak depolarization; the first-order reflected diffraction exhibits both linear and circular anisotropies and has stronger depolarization than the transmission mode. These results are different from previously published research. The Mueller matrix ellipsometer and polar decomposition method will aid in the investigation of the polarization properties of other nanostructures. PMID:26915332

Proceedings of U. S. Workshop on the Physics and Chemistry of Mercury Cadmium Telluride and Other IR Materials, Held in Danvers, Massachusetts on October 13 - 15, 1992

DTIC Science & Technology

1992-10-15

1011 4. R.D. Feldman, D. Lee, A. Partovi, R.P. Stanley, A.M. Johnson. J.E. Zucker, A.M. Glass and J. Hegarty, Critical Rev. SolidBromine 2 x 101 State...Growth 72, 462 (1985). 63. R.L. Chou, M.S. Lin and K.S. Chou, App!. Phys. Lett. 48, 523 32. H.L. Glass , M.R. Appleby Woods, M.C. Buehnerkemper, D.L. (1986...0.0A1203 1.76 0.0 will be assumed throughout this paper unless stated TeO2 2.31 0.0 otherwise. Au 0.183 3.10 The most common usage of an ellipsometer in

PEALD grown high-k ZrO{sub 2} thin films on SiC group IV compound semiconductor

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

Khairnar, A. G., E-mail: agkhairnar@gmail.com; Patil, V. S.; Agrawal, K. S.

The study of ZrO{sub 2} thin films on SiC group IV compound semiconductor has been studied as a high mobility substrates. The ZrO{sub 2} thin films were deposited using the Plasma Enhanced Atomic Layer Deposition System. The thickness of the thin films were measured using ellipsometer and found to be 5.47 nm. The deposited ZrO{sub 2} thin films were post deposition annealed in rapid thermal annealing chamber at temperature of 400°Ð¡. The atomic force microscopy and X-гау photoelectron spectroscopy has been carried out to study the surface topography, roughness and chemical composition of thin film, respectively.

Giant Linear Nonreciprocity, Zero Reflection, and Zero Band Gap in Equilibrated Space-Time-Varying Media

NASA Astrophysics Data System (ADS)

Taravati, Sajjad

2018-06-01

This article presents a class of space-time-varying media with giant linear nonreciprocity, zero space-time local reflections, and zero photonic band gap. This is achieved via equilibrium in the electric and magnetic properties of unidirectionally space-time-modulated media. The enhanced nonreciprocity is accompanied by a larger sonic regime interval which provides extra design freedom for achieving strong nonreciprocity by a weak pumping strength. We show that the width of photonic band gaps in general periodic space-time permittivity- and permeability-modulated media is proportional to the absolute difference between the electric and magnetic pumping strengths. We derive a rigorous analytical solution for investigation of wave propagation and scattering from general periodic space-time permittivity- and permeability-modulated media. In contrast with weak photonic transitions, from the excited mode to its two adjacent modes, in conventional space-time permittivity-modulated media, in an equilibrated space-time-varying medium, strong photonic transitions occur from the excited mode to its four adjacent modes. We study the enhanced nonreciprocity and zero band gap in equilibrated space-time-modulated media by analysis of their dispersion diagrams. In contrast to conventional space-time permittivity-modulated media, equilibrated space-time media exhibit different phase and group velocities for forward and backward harmonics. Furthermore, the numerical simulation scheme of general space-time permittivity- and permeability-modulated media is presented, which is based on the finite-difference time-domain technique. Our analytical and numerical results provide insights into general space-time refractive-index-modulated media, paving the way toward optimal isolators, nonreciprocal integrated systems, and subharmonic frequency generators.

Psychometric properties of startle and corrugator response in NPU, Affective Picture Viewing, and Resting State tasks

PubMed Central

Kaye, Jesse T.; Bradford, Daniel E.; Curtin, John J.

2016-01-01

The current study provides a comprehensive evaluation of critical psychometric properties of commonly used psychophysiology laboratory tasks/measures within the NIMH RDoC. Participants (N = 128) completed the No Shock, Predictable Shock, Unpredictable Shock (NPU) task, Affective Picture Viewing task, and Resting State task at two study visits separated by one week. We examined potentiation/modulation scores in NPU (predictable or unpredictable shock vs. no shock) and Affective Picture Viewing tasks (pleasant or unpleasant vs. neutral pictures) for startle and corrugator responses with two commonly used quantification methods. We quantified startle potentiation/modulation scores with raw and standardized responses. We quantified corrugator potentiation/modulation in the time and frequency domains. We quantified general startle reactivity in the Resting State Task as the mean raw startle response during the task. For these three tasks, two measures, and two quantification methods we evaluated effect size robustness and stability, internal consistency (i.e., split-half reliability), and one-week temporal stability. The psychometric properties of startle potentiation in the NPU task were good but concerns were noted for corrugator potentiation in this task. Some concerns also were noted for the psychometric properties of both startle and corrugator modulation in the Affective Picture Viewing task, in particular for pleasant picture modulation. Psychometric properties of general startle reactivity in the Resting State task were good. Some salient differences in the psychometric properties of the NPU and Affective Picture Viewing tasks were observed within and across quantification methods. PMID:27167717

Optimal partitioning of random programs across two processors

NASA Technical Reports Server (NTRS)

Nicol, D. M.

1986-01-01

The optimal partitioning of random distributed programs is discussed. It is concluded that the optimal partitioning of a homogeneous random program over a homogeneous distributed system either assigns all modules to a single processor, or distributes the modules as evenly as possible among all processors. The analysis rests heavily on the approximation which equates the expected maximum of a set of independent random variables with the set's maximum expectation. The results are strengthened by providing an approximation-free proof of this result for two processors under general conditions on the module execution time distribution. It is also shown that use of this approximation causes two of the previous central results to be false.

Ellipsometric study of YBa2Cu3O(7-x) laser ablated and co-evaporated films

NASA Technical Reports Server (NTRS)

Alterovitz, S. A.; Sieg, R. E.; Warner, J. D.; Stan, M. A.; Vitta, S.

1990-01-01

High temperature superconducting films of YBa2Cu3O(7-x) (YBCO were grown on SrTiO3, LaA1O3, and YSZ substrates using two techniques: excimer laser ablation with in situ annealing and co-evaporation of Y, Cu, and BaF2 with ex-situ annealing. Film thicknesses were typically 5000 A, with predominant c-axis alignment perpendicular to the substrate. Critical temperatures up to Tc(R=O)=90 K were achieved by both techniques. Ellipsometric measurements were taken in the range 1.6 to 4.3 eV using a variable angle spectroscopic ellipsometer. The complex dielectric function of the laser ablated films was reproducible from run to run, and was found to be within 10 percent of that previously reported for (001) oriented single crystals. A dielectric overlayer was observed in these films, with an index of refraction of approximately 1.55 and nearly zero absorption. For the laser ablated films the optical properties were essentially independent of substrate material. The magnitude of the dielectric function obtained for the co-evaported films was much lower than the value reported for single crystals, and was sample dependent.

General n-dimensional quadrature transform and its application to interferogram demodulation.

PubMed

Servin, Manuel; Quiroga, Juan Antonio; Marroquin, Jose Luis

2003-05-01

Quadrature operators are useful for obtaining the modulating phase phi in interferometry and temporal signals in electrical communications. In carrier-frequency interferometry and electrical communications, one uses the Hilbert transform to obtain the quadrature of the signal. In these cases the Hilbert transform gives the desired quadrature because the modulating phase is monotonically increasing. We propose an n-dimensional quadrature operator that transforms cos(phi) into -sin(phi) regardless of the frequency spectrum of the signal. With the quadrature of the phase-modulated signal, one can easily calculate the value of phi over all the domain of interest. Our quadrature operator is composed of two n-dimensional vector fields: One is related to the gradient of the image normalized with respect to local frequency magnitude, and the other is related to the sign of the local frequency of the signal. The inner product of these two vector fields gives us the desired quadrature signal. This quadrature operator is derived in the image space by use of differential vector calculus and in the frequency domain by use of a n-dimensional generalization of the Hilbert transform. A robust numerical algorithm is given to find the modulating phase of two-dimensional single-image closed-fringe interferograms by use of the ideas put forward.

Two-rowed Hecke algebra representations at roots of unity

NASA Astrophysics Data System (ADS)

Welsh, Trevor Alan

1996-02-01

In this paper, we initiate a study into the explicit construction of irreducible representations of the Hecke algebraH n (q) of typeA n-1 in the non-generic case whereq is a root of unity. The approach is via the Specht modules ofH n (q) which are irreducible in the generic case, and possess a natural basis indexed by Young tableaux. The general framework in which the irreducible non-genericH n (q)-modules are to be constructed is set up and, in particular, the full set of modules corresponding to two-part partitions is described. Plentiful examples are given.

Heterodyne interferometer with angstrom-level periodic nonlinearity

DOEpatents

Schmitz, Tony L.; Beckwith, John F.

2005-01-25

Displacement measuring interferometer systems and methods are disclosed. One or more acousto-optic modulators for receiving a laser light beam from a laser light source can be utilized to split the laser light beam into two or more laser light beams, while spatially separating frequencies thereof. One or more reflective mechanisms can be utilized to reflect one or more of the laser light beams back to the acousto-optic modulator. Interference of two or more of the laser light beams generally at the acousto-optic modulator can provide an interfered laser light beam thereof. A detector for receiving the interfered laser light beam can be utilized to provide interferometer measurement data.

Measures of Autonomic Nervous System Regulation

DTIC Science & Technology

2011-04-01

and most often used measures of ANS activation encompass non-invasive tools, which measure cardiac, skin conductance, respiratory , and vascular...regulation, osmotic balance, metabolism, digestion, excretion, and cardiac and respiratory activity. The ANS consists of the sympathetic and...modulate heart rate, as a function of the respiratory cycles. Generally, these two systems should be seen as permanently modulating vital functions to

ELLIPSOMETRY OF ELECTROCHEMICAL SURFACE LAYERS

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

Muller, R.H.

1977-06-01

Ellipsometry is concerned with the analysis and interpretation of changes in the state of polarization caused by reflection. The technique has found increasing interest in recent years for the measurement of thin films because it is unusually sensitive, disturbs the object minimally and can be applied to surfaces contained in any optically transparent medium. Film thicknesses amenable to measurement range from fractional monoatomic coverage to microscopic thicknesses. The measurement of changes in the state of polarization of light due to reflection provides an unusually sensitive tool for observing surface layers in any optically transparent environment. A fast, self-compensating ellipsometer hasmore » been used to observe the electrochemical formation of reacted surface layers. The optical effect of mass-transport boundary layers and component imperfections have been taken into account in the interpretation of results.« less

Ligand exchange and MIP-based paraoxon memories onto QCM sensor

NASA Astrophysics Data System (ADS)

Birlik Özkütük, Ebru; Emir Diltemiz, Sibel; Özalp, Elif; Uzun, Lokman; Ersöz, Arzu

2015-04-01

In this study, we have aimed to prepare quartz crystal microbalance (QCM) sensor using paraoxon-imprinted particles. Firstly, methacryloyl antipyrine (MAAP)-based metal-chelate-coordinated pre-complex has been prepared and used for paraoxon templation. Then, paraoxon-imprinted nanofilms were formed on QCM sensor after modification of the gold surfaces with allyl mercaptan. By this way, specific and selective memories, which depend on metal-chelate interactions between Eu(III) ions and template, for paraoxon molecules have been obtained on the electrode surface. QCM sensor has characterized using AFM and ellipsometer. The detection limit and the affinity constant have found to be 0.09 μM and 5.71 × 103 M-1 for MAAP-Eu paraoxon-based nanofilm, respectively. The specificity of the QCM sensor has shown using parathion as a competitor molecule.

Nonadiabatic effects in periodically driven dissipative open quantum systems

NASA Astrophysics Data System (ADS)

Reimer, Viktor; Pedersen, Kim G. L.; Tanger, Niklas; Pletyukhov, Mikhail; Gritsev, Vladimir

2018-04-01

We present a general method to calculate the periodic steady state of a driven-dissipative system coupled to a transmission line (and more generally, to a reservoir) under periodic modulation of its parameters. Using Floquet's theorem, we formulate the differential equation for the system's density operator which has to be solved for a single period of modulation. On this basis we also provide systematic expansions in both the adiabatic and high-frequency regime. Applying our method to three different systems—two- and three-level models as well as the driven nonlinear cavity—we propose periodic modulation protocols of parameters leading to a temporary suppression of effective dissipation rates, and study the arising nonadiabatic features in the response of these systems.

Characterisation of slab waveguides, fabricated in CaF2 and Er-doped tungsten-tellurite glass by MeV energy N+ ion implantation, using spectroscopic ellipsometry and m-line spectroscopy

NASA Astrophysics Data System (ADS)

Bányász, I.; Berneschi, S.; Lohner, T.; Fried, M.; Petrik, P.; Khanh, N. Q.; Zolnai, Z.; Watterich, A.; Bettinelli, M.; Brenci, M.; Nunzi-Conti, G.; Pelli, S.; Righini, G. C.; Speghini, A.

2010-05-01

Slab waveguides were fabricated in Er-doped tungsten-tellurite glass and CaF2 crystal samples via ion implantation. Waveguides were fabricated by implantation of MeV energy N+ ions at the Van de Graaff accelerator of the Research Institute for Particle and Nuclear Physics, Budapest, Hungary. Part of the samples was annealed. Implantations were carried out at energies of 1.5 MeV (tungsten-tellurite glass) and 3.5 MeV (CaF2). The implanted doses were between 5 x 1012 and 8 x 1016 ions/cm2. Refractive index profile of the waveguides was measured using SOPRA ES4G and Woollam M-2000DI spectroscopic ellipsometers at the Research Institute for Technical Physics and Materials Science, Budapest. Functionality of the waveguides was tested using a home-made instrument (COMPASSO), based on m-line spectroscopy and prism coupling technique, which was developed at the Materials and Photonics Devices Laboratory (MDF Lab.) of the Institute of Applied Physics in Sesto Fiorentino, Italy. Results of both types of measurements were compared to depth distributions of nuclear damage in the samples, calculated by SRIM 2007 code. Thicknesses of the guiding layer and of the implanted barrier obtained by spectroscopic ellipsometry correspond well to SRIM simulations. Irradiationinduced refractive index modulation saturated around a dose of 8 x 1016 ions/cm2 in tungsten-tellurite glass. Annealing of the implanted waveguides resulted in a reduction of the propagation loss, but also reduced the number of supported guiding modes at the lower doses. We report on the first working waveguides fabricated in an alkali earth halide crystal implanted by MeV energy medium-mass ions.

Predicting Response to Therapist-Assisted Internet-Delivered Cognitive Behavior Therapy for Depression or Anxiety Within an Open Dissemination Trial.

PubMed

Hadjistavropoulos, Heather D; Pugh, Nicole E; Hesser, Hugo; Andersson, Gerhard

2016-03-01

Therapist-assisted Internet-delivered cognitive behavior therapy (ICBT) is efficacious for treating anxiety and depression, but predictors of response to treatment when delivered in clinical practice are not well understood. In this study, we explored demographic, clinical, and program variables that predicted modules started and symptom improvement (i.e., Generalized Anxiety Disorder-7 or Patient Health Questionnaire-9 total scores over pre-, mid-, and posttreatment) within a previously published open dissemination trial (Hadjistavropoulos et al., 2014). The sample consisted of 195 patients offered 12 modules of therapist-assisted ICBT for depression or generalized anxiety; ICBT was delivered by therapists working in six geographically dispersed clinics. Consistent across ICBT for depression or generalized anxiety, starting fewer modules was associated with more phone calls from therapists reflecting that therapists tended to call patients who did not start modules as scheduled. Also consistent for both ICBT programs, greater pretreatment condition severity and completion of more modules was associated with superior ICBT-derived benefit. Other predictors of response to treatment varied across the two programs. Younger age, lower education, taking psychotropic medication, being in receipt of psychiatric care and lower comfort with written communication were associated with either fewer program starts or lower symptom improvement in one of the two programs. It is concluded that monitoring response to ICBT may be particularly important in patients with these characteristics. Research directions for identifying patients who are less likely to benefit from ICBT are discussed. Copyright © 2015. Published by Elsevier Ltd.

Bottom-Up and Top-Down Mechanisms of General Anesthetics Modulate Different Dimensions of Consciousness

PubMed Central

Mashour, George A.; Hudetz, Anthony G.

2017-01-01

There has been controversy regarding the precise mechanisms of anesthetic-induced unconsciousness, with two salient approaches that have emerged within systems neuroscience. One prominent approach is the “bottom up” paradigm, which argues that anesthetics suppress consciousness by modulating sleep-wake nuclei and neural circuits in the brainstem and diencephalon that have evolved to control arousal states. Another approach is the “top-down” paradigm, which argues that anesthetics suppress consciousness by modulating the cortical and thalamocortical circuits involved in the integration of neural information. In this article, we synthesize these approaches by mapping bottom-up and top-down mechanisms of general anesthetics to two distinct but inter-related dimensions of consciousness: level and content. We show how this explains certain empirical observations regarding the diversity of anesthetic drug effects. We conclude with a more nuanced discussion of how levels and contents of consciousness interact to generate subjective experience and what this implies for the mechanisms of anesthetic-induced unconsciousness. PMID:28676745

Bottom-Up and Top-Down Mechanisms of General Anesthetics Modulate Different Dimensions of Consciousness.

PubMed

Mashour, George A; Hudetz, Anthony G

2017-01-01

There has been controversy regarding the precise mechanisms of anesthetic-induced unconsciousness, with two salient approaches that have emerged within systems neuroscience. One prominent approach is the "bottom up" paradigm, which argues that anesthetics suppress consciousness by modulating sleep-wake nuclei and neural circuits in the brainstem and diencephalon that have evolved to control arousal states. Another approach is the "top-down" paradigm, which argues that anesthetics suppress consciousness by modulating the cortical and thalamocortical circuits involved in the integration of neural information. In this article, we synthesize these approaches by mapping bottom-up and top-down mechanisms of general anesthetics to two distinct but inter-related dimensions of consciousness: level and content. We show how this explains certain empirical observations regarding the diversity of anesthetic drug effects. We conclude with a more nuanced discussion of how levels and contents of consciousness interact to generate subjective experience and what this implies for the mechanisms of anesthetic-induced unconsciousness.

Performance Analysis and Design Synthesis (PADS) computer program. Volume 1: Formulation

NASA Technical Reports Server (NTRS)

1972-01-01

The program formulation for PADS computer program is presented. It can size launch vehicles in conjunction with calculus-of-variations optimal trajectories and can also be used as a general-purpose branched trajectory optimization program. In the former use, it has the Space Shuttle Synthesis Program as well as a simplified stage weight module for optimally sizing manned recoverable launch vehicles. For trajectory optimization alone or with sizing, PADS has two trajectory modules. The first trajectory module uses the method of steepest descent; the second employs the method of quasilinearization, which requires a starting solution from the first trajectory module.

Performance of RF sputtered p-Si/n-ZnO nanoparticle thin film heterojunction diodes in high temperature environment

NASA Astrophysics Data System (ADS)

Singh, Satyendra Kumar; Hazra, Purnima

2017-04-01

In this article, temperature-dependent current-voltage characteristics of n-ZnO/p-Si nanoparticle thin film heterojunction diode grown by RF sputtering technique are analyzed in the temperature range of 300-433 k to investigate the performance of the device in high temperature environment. The microstructural, morphological, optical and temptrature dependent electrical properties of as-grown nanoparticle thin film were characterized by X-ray diffractometer (XRD), atomic force microscopy (AFM), field emmision scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDX), variable angle ellipsometer and semiconductor device analyzer. XRD spectra of as-grown ZnO films are exhibited that highly c-axis oriented ZnO nanostructures are grown on p- Si〈100〉 substrate whereas AFM and FESEM images confirm the homogeneous deposition of ZnO nanoparticles on surface of Si substratewith minimum roughness.The optical propertiesof as-grown ZnO nanoparticles have been measured in the spectral range of 300-800 nm using variable angle ellipsometer.To measure electrical parameters of the device prototype in the temperature range of room temperature (300 K) to 433 K, large area ohmic contacts were fabricated on both side of the ZnO/Si heterostructure. From the current-voltage charcteristics of ZnO/Si heterojunction device, it is observed that the device exhibits rectifing nature at room temperature. However, with increase in temperature, reverse saturation current and barrier height are found to increase, whereas ideality factor is started decreasing. This phenomenon confirms that barrier inhomogeneities are present at the interface of ZnO/Si heterojunction, as a result of lattice constant and thermal coefficient mismatch between Si and ZnO. Therefore, a modified value of Richardson constant [33.06 Acm-2K-2] has been extracted from the temperature-dependent electrical characteristics after assuming the Gaussian distribution of special barrier height inhomogeneities across the Si/ZnO interface which is close to its theoretical value [32 Acm-2K-2]. This result indicates that regardless of presence of barrier height inmogeneities, ZnO/Si heterojunction diode still hasability to perform well in high temperature environment.

Life span and structure of ephemeral root modules of different functional groups from a desert system.

PubMed

Liu, Bo; He, Junxia; Zeng, Fanjiang; Lei, Jiaqiang; Arndt, Stefan K

2016-07-01

The terminal branch orders of plant root systems have been proposed as short-lived 'ephemeral' modules specialized for resource absorption. The occurrence of ephemeral root modules has so far only been reported for a temperate tree species and it is unclear if the concept also applies to other woody (shrub, tree) and herb species. Fine roots of 12 perennial dicotyledonous herb, shrub and tree species were monitored for two growing seasons using a branch-order classification, sequential sampling and rhizotrons in the Taklamakan desert. Two root modules existed in all three plant functional groups. Among the first five branch orders, the first two (perennial herbs, shrubs) or three (trees) root orders were ephemeral and had a primary anatomical structure, high nitrogen (N) concentrations, high respiration rates and very short life spans of 1-4 months, whereas the last two branch orders in all functional groups were perennial, with thicker diameters, no or collapsed cortex, distinct secondary growth, low N concentrations, low respiration rates, but much longer life spans. Ephemeral, short-lived root modules and long-lived, persistent root modules seem to be a general feature across many plant functional groups and could represent a basic root system design. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

NASGRO 3.0: A Software for Analyzing Aging Aircraft

NASA Technical Reports Server (NTRS)

Mettu, S. R.; Shivakumar, V.; Beek, J. M.; Yeh, F.; Williams, L. C.; Forman, R. G.; McMahon, J. J.; Newman, J. C., Jr.

1999-01-01

Structural integrity analysis of aging aircraft is a critical necessity in view of the increasing numbers of such aircraft in general aviation, the airlines and the military. Efforts are in progress by NASA, the FAA and the DoD to focus attention on aging aircraft safety. The present paper describes the NASGRO software which is well-suited for effectively analyzing the behavior of defects that may be found in aging aircraft. The newly revised Version 3.0 has many features specifically implemented to suit the needs of the aircraft community. The fatigue crack growth computer program NASA/FLAGRO 2.0 was originally developed to analyze space hardware such as the Space Shuttle, the International Space Station and the associated payloads. Due to popular demand, the software was enhanced to suit the needs of the aircraft industry. Major improvements in Version 3.0 are the incorporation of the ability to read aircraft spectra of unlimited size, generation of common aircraft fatigue load blocks, and the incorporation of crack-growth models which include load-interaction effects such as retardation due to overloads and acceleration due to underloads. Five new crack-growth models, viz., generalized Willenborg, modified generalized Willenborg, constant closure model, Walker-Chang model and the deKoning-Newman strip-yield model, have been implemented. To facilitate easier input of geometry, material properties and load spectra, a Windows-style graphical user interface has been developed. Features to quickly change the input and rerun the problem as well as examine the output are incorporated. NASGRO has been organized into three modules, the crack-growth module being the primary one. The other two modules are the boundary element module and the material properties module. The boundary-element module provides the ability to model and analyze complex two-dimensional problems to obtain stresses and stress-intensity factors. The material properties module allows users to store and curve-fit fatigue-crack growth data. On-line help and documentation are provided for each of the modules. In addition to the popular PC windows version, a unix-based X-windows version of NASGRO is also available. A portable C++ class library called WxWindows was used to facilitate cross-platform availability of the software.

Design Development of the Apollo Lunar Module

NASA Technical Reports Server (NTRS)

Cox, K. L.

1978-01-01

The lunar module autopilot is a first generation digital control system design. The two torque sources available for the control function of the descent stage configuration consist of 16 reaction jets and a slow, gimbaled, throttlable engine. Design history, the design requirements, criteria, constraints, and general design philosophy of the control system development are reviewed. Comparative flight test results derived from design testing are presented.

Frequency Hopping, Multiple Frequency-Shift Keying, Coding, and Optimal Partial-Band Jamming.

DTIC Science & Technology

1982-08-01

receivers appropriate for these two strategies. Each receiver is noncoherent (a coherent receiver is generally impractical) and implements hard...Advances in Coding and Modulation for Noncoherent Channels Affected by Fading, Partial Band, and Multiple- . Access Interference, in A. J. Viterbi...Modulation for Noncoherent Channels Affected by Fading, Partial Band, and Multiple-Access interference, in A. J. Viterbi, ed., Advances in Coumunication

Analysis of frequency mixing error on heterodyne interferometric ellipsometry

NASA Astrophysics Data System (ADS)

Deng, Yuan-long; Li, Xue-jin; Wu, Yu-bin; Hu, Ju-guang; Yao, Jian-quan

2007-11-01

A heterodyne interferometric ellipsometer, with no moving parts and a transverse Zeeman laser, is demonstrated. The modified Mach-Zehnder interferometer characterized as a separate frequency and common-path configuration is designed and theoretically analyzed. The experimental data show a fluctuation mainly resulting from the frequency mixing error which is caused by the imperfection of polarizing beam splitters (PBS), the elliptical polarization and non-orthogonality of light beams. The producing mechanism of the frequency mixing error and its influence on measurement are analyzed with the Jones matrix method; the calculation indicates that it results in an error up to several nanometres in the thickness measurement of thin films. The non-orthogonality has no contribution to the phase difference error when it is relatively small; the elliptical polarization and the imperfection of PBS have a major effect on the error.

Direct conversion of solar energy to thermal energy

NASA Astrophysics Data System (ADS)

Sizmann, Rudolf

1986-12-01

Selective coatings (cermets) were produced by simultaneous evaporation of copper and silicon dioxide, and analyzed by computer assisted spectral photometers and ellipsometers; hemispherical emittance was measured. Steady state test procedures for covered and uncovered collectors were investigated. A method for evaluating the transient behavior of collectors was developed. The derived transfer functions describe their transient behavior. A stochastic approach was used for reducing the meteorological data volume. Data sets which are statistically equivalent to the original data can be synthesized. A simulation program for solar systems using analytical solutions of differential equations was developed. A large solar DHW system was optimized by a detailed modular simulation program. A microprocessor assisted data aquisition records the four characteristics of solar cells and solar cell systems in less than 10 msec. Measurements of a large photovoltaic installation (50 sqm) are reported.

Yetter-Drinfeld modules for Hom-bialgebras

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

Makhlouf, Abdenacer, E-mail: Abdenacer.Makhlouf@uha.fr; Panaite, Florin, E-mail: Florin.Panaite@imar.ro

The aim of this paper is to define and study Yetter-Drinfeld modules over Hom-bialgebras, a generalized version of bialgebras obtained by modifying the algebra and coalgebra structures by a homomorphism. Yetter-Drinfeld modules over a Hom-bialgebra with bijective structure map provide solutions of the Hom-Yang-Baxter equation. The category H/HYD of Yetter-Drinfeld modules with bijective structure maps over a Hom-bialgebra H with bijective structure map can be organized, in two different ways, as a quasi-braided pre-tensor category. If H is quasitriangular (respectively, coquasitriangular) the first (respectively, second) quasi-braided pre-tensor category H/HYD contains, as a quasi-braided pre-tensor subcategory, the category of modules (respectively,more » comodules) with bijective structure maps over H.« less

Statistical process control using optimized neural networks: a case study.

PubMed

Addeh, Jalil; Ebrahimzadeh, Ata; Azarbad, Milad; Ranaee, Vahid

2014-09-01

The most common statistical process control (SPC) tools employed for monitoring process changes are control charts. A control chart demonstrates that the process has altered by generating an out-of-control signal. This study investigates the design of an accurate system for the control chart patterns (CCPs) recognition in two aspects. First, an efficient system is introduced that includes two main modules: feature extraction module and classifier module. In the feature extraction module, a proper set of shape features and statistical feature are proposed as the efficient characteristics of the patterns. In the classifier module, several neural networks, such as multilayer perceptron, probabilistic neural network and radial basis function are investigated. Based on an experimental study, the best classifier is chosen in order to recognize the CCPs. Second, a hybrid heuristic recognition system is introduced based on cuckoo optimization algorithm (COA) algorithm to improve the generalization performance of the classifier. The simulation results show that the proposed algorithm has high recognition accuracy. Copyright © 2013 ISA. Published by Elsevier Ltd. All rights reserved.

Material growth and characterization for solid state devices

NASA Technical Reports Server (NTRS)

Stefanakos, E. K.; Collis, W. J.; Abul-Fadl, A.; Iyer, S.

1984-01-01

Manganese was used as the dopant for p-type InGaAs layers grown on semi-insulating (Fe-doped) and n-type (Sn-doped) InP substrates. Optical, electrical (Hall) and SIMS measurements were used to characterize the layers. Mn-diffusion into the substrate (during the growth of In GaAs) was observed only when Fe-doped substrates were used. Quaternary layers of two compositions corresponding to wavelengths (energy gaps) of approximated 1.52 micrometers were successfully grown at a constant temperature of 640 C and InP was grown in the temperature range of 640 C to 655 C. A study of the effect of pulses on the growth velocity of InP indicated no significant change as long as the average applied current was kept constant. A system for depositing films of Al2O3 by the pyrolysis of aluminum isopropoxide was designed and built. Deposited layers on Si were characterized with an ellipsometer and exhibited indices of refraction between 1.582 and 1.622 for films on the order of 3000 A thick. Undoped and p-type (Mn-doped) InGaAs epitaxial layers were also grown on Fe-doped InP substrates through windows in sputtered SiO2 (3200 A thick) layers.

Optical constants of electroplated gold from spectroscopic ellipsometry

NASA Astrophysics Data System (ADS)

Synowicki, R. A.; Herzinger, Craig M.; Hall, James T.; Malingowski, Andrew

2017-11-01

The optical constants of an opaque electroplated gold film (Laser Gold from Epner Technology Inc.), were determined by spectroscopic ellipsometry at room temperature over the spectral range from 0.142 μm in the vacuum ultraviolet to 36 μm in the infrared (photon energy range 0.034-8.75 eV). Data from two separate ellipsometer instruments covering different spectral ranges were analyzed simultaneously. The optical constants n&k or ε1&ε2 were determined by fitting an oscillator dispersion model combining Drude, Gaussian, and Sellmeier dispersion functions to the experimental Ψ and Δ data. The data were analyzed using both an ideal bulk substrate model and a simple overlayer model to account for surface roughness. Including the optical surface roughness layer improved ellipsometric data fits in the UV, and using a separate Drude function for the surface layer improved fits in the infrared. The surface roughness was also characterized using an Atomic Force Microscope. Using an oscillator dispersion model for the optical constants determined in this work allows for more realistic extrapolation to longer infrared wavelengths. Extending optical constants out to 50 μm and beyond is important for calibrating far-infrared reflectance measurements. Applications include understanding the thermal performance of cryogenic space-based instruments, such as the James Webb Space Telescope (JWST).

Combined ellipsometry and refractometry technique for characterisation of liquid crystal based nanocomposites.

PubMed

Warenghem, Marc; Henninot, Jean François; Blach, Jean François; Buchnev, Oleksandr; Kaczmarek, Malgosia; Stchakovsky, Michel

2012-03-01

Spectroscopic ellipsometry is a technique especially well suited to measure the effective optical properties of a composite material. However, as the sample is optically thick and anisotropic, this technique loses its accuracy for two reasons: anisotropy means that two parameters have to be determined (ordinary and extraordinary indices) and optically thick means a large order of interference. In that case, several dielectric functions can emerge out of the fitting procedure with a similar mean square error and no criterion to discriminate the right solution. In this paper, we develop a methodology to overcome that drawback. It combines ellipsometry with refractometry. The same sample is used in a total internal reflection (TIR) setup and in a spectroscopic ellipsometer. The number of parameters to be determined by the fitting procedure is reduced in analysing two spectra, the correct final solution is found by using the TIR results both as initial values for the parameters and as check for the final dielectric function. A prefitting routine is developed to enter the right initial values in the fitting procedure and so to approach the right solution. As an example, this methodology is used to analyse the optical properties of BaTiO(3) nanoparticles embedded in a nematic liquid crystal. Such a methodology can also be used to analyse experimentally the validity of the mixing laws, since ellipsometry gives the effective dielectric function and thus, can be compared to the dielectric function of the components of the mixture, as it is shown on the example of BaTiO(3)/nematic composite.

Hypertension module: an interactive learning tool in physiology.

PubMed

Işman, C A; Gülpinar, M A; Kurtel, H; Alican, I; Yeğen, B C

2003-12-01

The aim of the present study was to evaluate the strong or weak aspects of an interactive study module introduced during the "Cardiovascular and Respiratory Systems Subject Committee" in the second year of the medical program. Five study groups consisting of 25 students attended two-hour module sessions for six weeks with the same tutor. According to the module assessment questionnaire, the majority of the students assessed the module as excellent or good. The students reported that they had gained not only in knowledge but also in skills development. The general opinion of the students was that both the organization and the implementation of the module met their expectations. Nearly one-half of the students reported that their expectations with regard to the educational environment and the participation of students were fully met. The major weakness in this new educational trial appears to be assessment of the module.

Demystifying the Chemistry Literature: Building Information Literacy in First-Year Chemistry Students through Student-Centered Learning and Experiment Design

ERIC Educational Resources Information Center

Bruehl, Margaret; Pan, Denise; Ferrer-Vinent, Ignacio J.

2015-01-01

This paper describes curriculum modules developed for first-year general chemistry laboratory courses that use scientific literature and creative experiment design to build information literacy in a student-centered learning environment. Two curriculum units are discussed: Exploring Scientific Literature and Design Your Own General Chemistry…

Simulating transient dynamics of the time-dependent time fractional Fokker-Planck systems

NASA Astrophysics Data System (ADS)

Kang, Yan-Mei

2016-09-01

For a physically realistic type of time-dependent time fractional Fokker-Planck (FP) equation, derived as the continuous limit of the continuous time random walk with time-modulated Boltzmann jumping weight, a semi-analytic iteration scheme based on the truncated (generalized) Fourier series is presented to simulate the resultant transient dynamics when the external time modulation is a piece-wise constant signal. At first, the iteration scheme is demonstrated with a simple time-dependent time fractional FP equation on finite interval with two absorbing boundaries, and then it is generalized to the more general time-dependent Smoluchowski-type time fractional Fokker-Planck equation. The numerical examples verify the efficiency and accuracy of the iteration method, and some novel dynamical phenomena including polarized motion orientations and periodic response death are discussed.

Convective and morphological instabilities during crystal growth: Effect of gravity modulation

NASA Technical Reports Server (NTRS)

Coreill, S. R.; Murray, B. T.; Mcfadden, G. B.; Wheeler, A. A.; Saunders, B. V.

1992-01-01

During directional solidification of a binary alloy at constant velocity in the vertical direction, morphological and convective instabilities may occur due to the temperature and solute gradients associated with the solidification process. The effect of time-periodic modulation (vibration) is studied by considering a vertical gravitational acceleration which is sinusoidal in time. The conditions for the onset of solutal convection are calculated numerically, employing two distinct computational procedures based on Floquet theory. In general, a stable state can be destabilized by modulation and an unstable state can be stabilized. In the limit of high frequency modulation, the method of averaging and multiple-scale asymptotic analysis can be used to simplify the calculations.

Three-dimensional spatiotemporal focusing of holographic patterns

PubMed Central

Hernandez, Oscar; Papagiakoumou, Eirini; Tanese, Dimitrii; Fidelin, Kevin; Wyart, Claire; Emiliani, Valentina

2016-01-01

Two-photon excitation with temporally focused pulses can be combined with phase-modulation approaches, such as computer-generated holography and generalized phase contrast, to efficiently distribute light into two-dimensional, axially confined, user-defined shapes. Adding lens-phase modulations to 2D-phase holograms enables remote axial pattern displacement as well as simultaneous pattern generation in multiple distinct planes. However, the axial confinement linearly degrades with lateral shape area in previous reports where axially shifted holographic shapes were not temporally focused. Here we report an optical system using two spatial light modulators to independently control transverse- and axial-target light distribution. This approach enables simultaneous axial translation of single or multiple spatiotemporally focused patterns across the sample volume while achieving the axial confinement of temporal focusing. We use the system's capability to photoconvert tens of Kaede-expressing neurons with single-cell resolution in live zebrafish larvae. PMID:27306044

Spatial Light Modulators and Applications: Summaries of Papers Presented at the Spatial Light Modulators and Applications Topical Meeting Held on March 15-17, 1993 in Palm Springs, California

DTIC Science & Technology

1993-03-17

modulator: Number of Elements 16 x 16 Pixel Size 1 mmxl mm Area Fill Factor > 90% Reflectance > 90% Phase Shift 900 Frame Rate > 1 kHz Operational Spectral...electro-optic constants. By using reflected light from the second interface a factor of two increase in phase shift is obtained for an applied voltage vs...wavelengths in general require thinner PLZT wafers. One of the objectives of the SLM design was to maximize pixel area fill factor and thereby the

AQUATOOL, a generalized decision-support system for water-resources planning and operational management

NASA Astrophysics Data System (ADS)

Andreu, J.; Capilla, J.; Sanchís, E.

1996-04-01

This paper describes a generic decision-support system (DSS) which was originally designed for the planning stage of dicision-making associated with complex river basins. Subsequently, it was expanded to incorporate modules relating to the operational stage of decision-making. Computer-assisted design modules allow any complex water-resource system to be represented in graphical form, giving access to geographically referenced databases and knowledge bases. The modelling capability includes basin simulation and optimization modules, an aquifer flow modelling module and two modules for risk assessment. The Segura and Tagus river basins have been used as case studies in the development and validation phases. The value of this DSS is demonstrated by the fact that both River Basin Agencies currently use a version for the efficient management of their water resources.

The influence of nonstationarity of the solar activity and general solar field on modulation of cosmic rays

NASA Technical Reports Server (NTRS)

Zusmanovich, A. G.; Kryakunova, O. N.; Churunova, L. F.; Shvartsman, Y. E.

1985-01-01

A numerical model of the propagation of galactic cosmic rays in interplanetary space was constructed for the case when the modulation depth determined by the level of solar activity changed in time. Also the contribution of particle drift in the regular field was calculated, and the agreement with experimental data concerning the ratio of protons and electrons in two solar activity minima is shown.

The Decision Module Working Paper

DTIC Science & Technology

1973-12-01

and goal change has received very little attention In the litera- ture on the analysis of choice situations. It has generally been the case that the...Decision Making: Approach and Prototype" (197:0, done In context of the Mesarovlc - Pestel World Model Projet’ The Issues dealing with «-he cho ce...Nelson, Winder, and Schuette (1973) on evolutionary economic growth models. The discussion of the two components of the decision module that follows

Classification and Evaluation of Coherent Synchronous Sampled-Data Telemetry Systems

NASA Technical Reports Server (NTRS)

Viterbi, Andrew

1961-01-01

This paper analyzes the various types of continuous wave and pulse modulation for the transmission of sampled data over channels perturbed by white gaussian noise. Optimal coherent synchronous detection schemes for all the different modulation methods are shown to belong to one of two general classes: linear synchronous detection and correlation detection. The figures of merit, mean-square signal-to-error ratio and bandwidth occupancy, are determined for each system and compared.

Evaluation and study of advanced optical contamination, deposition, measurement, and removal techniques. [including computer programs and ultraviolet reflection analysis

NASA Technical Reports Server (NTRS)

Linford, R. M. F.; Allen, T. H.; Dillow, C. F.

1975-01-01

A program is described to design, fabricate and install an experimental work chamber assembly (WCA) to provide a wide range of experimental capability. The WCA incorporates several techniques for studying the kinetics of contaminant films and their effect on optical surfaces. It incorporates the capability for depositing both optical and contaminant films on temperature-controlled samples, and for in-situ measurements of the vacuum ultraviolet reflectance. Ellipsometer optics are mounted on the chamber for film thickness determinations, and other features include access ports for radiation sources and instrumentation. Several supporting studies were conducted to define specific chamber requirements, to determine the sensitivity of the measurement techniques to be incorporated in the chamber, and to establish procedures for handling samples prior to their installation in the chamber. A bibliography and literature survey of contamination-related articles is included.

Perspective: Optical measurement of feature dimensions and shapes by scatterometry

NASA Astrophysics Data System (ADS)

Diebold, Alain C.; Antonelli, Andy; Keller, Nick

2018-05-01

The use of optical scattering to measure feature shape and dimensions, scatterometry, is now routine during semiconductor manufacturing. Scatterometry iteratively improves an optical model structure using simulations that are compared to experimental data from an ellipsometer. These simulations are done using the rigorous coupled wave analysis for solving Maxwell's equations. In this article, we describe the Mueller matrix spectroscopic ellipsometry based scatterometry. Next, the rigorous coupled wave analysis for Maxwell's equations is presented. Following this, several example measurements are described as they apply to specific process steps in the fabrication of gate-all-around (GAA) transistor structures. First, simulations of measurement sensitivity for the inner spacer etch back step of horizontal GAA transistor processing are described. Next, the simulated metrology sensitivity for sacrificial (dummy) amorphous silicon etch back step of vertical GAA transistor processing is discussed. Finally, we present the application of plasmonically active test structures for improving the sensitivity of the measurement of metal linewidths.

Hierarchical surface code for network quantum computing with modules of arbitrary size

NASA Astrophysics Data System (ADS)

Li, Ying; Benjamin, Simon C.

2016-10-01

The network paradigm for quantum computing involves interconnecting many modules to form a scalable machine. Typically it is assumed that the links between modules are prone to noise while operations within modules have a significantly higher fidelity. To optimize fault tolerance in such architectures we introduce a hierarchical generalization of the surface code: a small "patch" of the code exists within each module and constitutes a single effective qubit of the logic-level surface code. Errors primarily occur in a two-dimensional subspace, i.e., patch perimeters extruded over time, and the resulting noise threshold for intermodule links can exceed ˜10 % even in the absence of purification. Increasing the number of qubits within each module decreases the number of qubits necessary for encoding a logical qubit. But this advantage is relatively modest, and broadly speaking, a "fine-grained" network of small modules containing only about eight qubits is competitive in total qubit count versus a "course" network with modules containing many hundreds of qubits.

Very-low-power and footprint integrated photonic modulators and switches for ICT

NASA Astrophysics Data System (ADS)

Thylén, Lars; Holmström, Petter; Wosinski, Lech

2013-03-01

The current development in photonics for communications and interconnects pose increasing requirements on reduction of footprint, power dissipation and cost, as well as increased bandwidth. Integrated nanophotonics has been viewed as one solution to this, capitalizing on development in nanotechnology as such as well as on increased insights into light matter interaction on the nanoscale. The latter can be exemplified by plasmonics and low-dimensional semiconductors such as quantum dots (QDs). In this scenario the development of better electrooptic materials is also of great importance, the electrooptic polymers being an example, since they potentially offer improved properties for optical phase modulators in terms of power and probably cost and general flexibility. Phase modulators are essential for e.g. the rapidly developing advanced modulation formats for telecom, since phase modulation basically can generate any type of modulation. The electrooptic polymers, e.g. in combination with plasmonics nanoparticle array waveguides or nanostructured hybrid plasmonic media can theoretically give extremely compact and low power dissipation modulators, still to be demonstrated. The low-dimensional semiconductors, e.g. in the shape of QDs, can be employed for modulation or switching functions, offering possibilities in the future for scaling to 2 or 3 dimensions for advanced switching functions. In both the plasmonics and QD cases, nanosizing and low power dissipation are generally due to near-field interactions, albeit being of different physical origin in the two cases. A comparison of all-optical and electronically controlled switching is given.

Design of multifunction anti-terrorism robotic system based on police dog

NASA Astrophysics Data System (ADS)

You, Bo; Liu, Suju; Xu, Jun; Li, Dongjie

2007-11-01

Aimed at some typical constraints of police dogs and robots used in the areas of reconnaissance and counterterrorism currently, the multifunction anti-terrorism robotic system based on police dog has been introduced. The system is made up of two parts: portable commanding device and police dog robotic system. The portable commanding device consists of power supply module, microprocessor module, LCD display module, wireless data receiving and dispatching module and commanding module, which implements the remote control to the police dogs and takes real time monitor to the video and images. The police dog robotic system consists of microprocessor module, micro video module, wireless data transmission module, power supply module and offence weapon module, which real time collects and transmits video and image data of the counter-terrorism sites, and gives military attack based on commands. The system combines police dogs' biological intelligence with micro robot. Not only does it avoid the complexity of general anti-terrorism robots' mechanical structure and the control algorithm, but it also widens the working scope of police dog, which meets the requirements of anti-terrorism in the new era.

Affine cellularity of finite type KLR algebras, and homomorphisms between Specht modules for KLR algebras in affine type A

NASA Astrophysics Data System (ADS)

Loubert, Joseph William

This thesis consists of two parts. In the first we prove that the Khovanov-Lauda-Rouquier algebras Ralpha of finite type are (graded) affine cellular in the sense of Koenig and Xi. In fact, we establish a stronger property, namely that the affine cell ideals in Ralpha are generated by idempotents. This in particular implies the (known) result that the global dimension of Ralpha is finite. In the second part we use the presentation of the Specht modules given by Kleshchev-Mathas-Ram to derive results about Specht modules. In particular, we determine all homomorphisms from an arbitrary Specht module to a fixed Specht module corresponding to any hook partition. Along the way, we give a complete description of the action of the standard KLR generators on the hook Specht module. This work generalizes a result of James. This dissertation includes previously published coauthored material.

Gain Modulation in the Central Nervous System: Where Behavior, Neurophysiology, and Computation Meet

PubMed Central

SALINAS, EMILIO; SEJNOWSKI, TERRENCE J.

2010-01-01

Gain modulation is a nonlinear way in which neurons combine information from two (or more) sources, which may be of sensory, motor, or cognitive origin. Gain modulation is revealed when one input, the modulatory one, affects the gain or the sensitivity of the neuron to the other input, without modifying its selectivity or receptive field properties. This type of modulatory interaction is important for two reasons. First, it is an extremely widespread integration mechanism; it is found in a plethora of cortical areas and in some subcortical structures as well, and as a consequence it seems to play an important role in a striking variety of functions, including eye and limb movements, navigation, spatial perception, attentional processing, and object recognition. Second, there is a theoretical foundation indicating that gain-modulated neurons may serve as a basis for a general class of computations, namely, coordinate transformations and the generation of invariant responses, which indeed may underlie all the brain functions just mentioned. This article describes the relationships between computational models, the physiological properties of a variety of gain-modulated neurons, and some of the behavioral consequences of damage to gain-modulated neural representations. PMID:11597102

Sea level history in Beringia during the past 250,000 years

USGS Publications Warehouse

Hopkins, D.M.

1973-01-01

This paper attempts to relate current knowledge of sea-level history in Beringia to the Broecker-van Donk "Termination" concept of climatic and sea-level history. The Einahnuhtan transgression is thought to represent Termination III, which according to Broecker and van Donk, took place about 225,000 y.a. The Kotzebuan transgression is thought to represent a positive fluctuation that modulated the generally falling sea level during the ensuing 100,000 yr. Sea level probably fell to about -135 m in the Bering Sea area during the maximum phase of the penultimate glaciation. The two Pelukian shorelines probably represent Termination II (about 125,000 yr BP in the Broecker-van Donk chronology) and one of the two positive fluctuations that modulated the generally falling sea level of early Wisconsinan time, about 105,000 and 80,000 y.a. according to Broecker and van Donk. Another positive modulation brought sea level to at least -20 m, about 30,000 y.a. Sea level evidently fell to between -90 and -100 m during the late Wisconsinan regression, but a substantial part of the outer Bering shelf remained submerged. Submerged shoreline features at -38m, -30 m, -24 to -20 m, and -12 to -10 m represent stillstands or slight regressions that modulated Termination I, the late Wisconsinan, and early Holocene recovery of sea level. ?? 1973.

In two minds: dual-process accounts of reasoning.

PubMed

Evans, Jonathan St B T

2003-10-01

Researchers in thinking and reasoning have proposed recently that there are two distinct cognitive systems underlying reasoning. System 1 is old in evolutionary terms and shared with other animals: it comprises a set of autonomous subsystems that include both innate input modules and domain-specific knowledge acquired by a domain-general learning mechanism. System 2 is evolutionarily recent and distinctively human: it permits abstract reasoning and hypothetical thinking, but is constrained by working memory capacity and correlated with measures of general intelligence. These theories essentially posit two minds in one brain with a range of experimental psychological evidence showing that the two systems compete for control of our inferences and actions.

Unidirectional invisibility and non-reciprocal transmission in two and three dimensions.

PubMed

Loran, Farhang; Mostafazadeh, Ali

2016-07-01

We explore the phenomenon of unidirectional invisibility in two dimensions, examine its optical realizations and discuss its three-dimensional generalization. In particular, we construct an infinite class of unidirectionally invisible optical potentials that describe the scattering of normally incident transverse electric waves by an infinite planar slab with refractive-index modulations along both the normal directions to the electric field. A by-product of this investigation is a demonstration of non-reciprocal transmission in two dimensions. To elucidate this phenomenon, we state and prove a general reciprocity theorem that applies to quantum scattering theory of real and complex potentials in two and three dimensions.

ANALYSIS OF SEEING-INDUCED POLARIZATION CROSS-TALK AND MODULATION SCHEME PERFORMANCE

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

Casini, R.; De Wijn, A. G.; Judge, P. G.

2012-09-20

We analyze the generation of polarization cross-talk in Stokes polarimeters by atmospheric seeing, and its effects on the noise statistics of spectropolarimetric measurements for both single-beam and dual-beam instruments. We investigate the time evolution of seeing-induced correlations between different states of one modulation cycle and compare the response to these correlations of two popular polarization modulation schemes in a dual-beam system. Extension of the formalism to encompass an arbitrary number of modulation cycles enables us to compare our results with earlier work. Even though we discuss examples pertinent to solar physics, the general treatment of the subject and its fundamentalmore » results might be useful to a wider community.« less

Microgravity

NASA Image and Video Library

1998-01-01

Engineering mockup shows the general arrangement of the plarned Biotechnology Facility inside an EXPRESS rack aboard the International Space Station. This layout includes a gas supply module (bottom left), control computer and laptop interface (bottom right), two rotating wall vessels (top right), and support systems.

Online Module for Carrier Screening in Ashkenazi Jewish Individuals Compared with In-Person Genetics Education: A Randomized Controlled Trial.

PubMed

Fan, Chia Wei; Castonguay, Lysanne; Rummell, Sonja; Lévesque, Sébastien; Mitchell, John J; Sillon, Guillaume

2018-04-01

To increase accessibility to genetics services for low-urgency patients seeking Ashkenazi Jewish (AJ) carrier screening, we designed an interactive computer (IC) module that provides pre-test genetics education and allows genetics professionals to order the test without meeting the patients beforehand. We compared this module with in-person genetic counseling (GC) using a randomized trial. AJ individuals were randomized to undergo genetics education via the IC module (n = 26) or GC (n = 28). We compared post-interventional genetics knowledge, perceived genetic risk, and anxiety between the two groups, after accounting for pre-interventional scores, using ANCOVA. Wilcoxon Rank-Sum test was used to compare post-interventional satisfaction. Post-interventional genetics knowledge, risk perception, or anxiety were not significantly different between the two groups after accounting for baseline scores (p = 0.50-0.54), although the data are inconclusive regarding the module's non-inferiority at a 5% margin. Post-intervention satisfaction scores were generally higher in the GC group than the IC module group. Our IC module has the potential to improve access to clinical genetics services for patients and staff, but it is not suitable for all AJ patients and cannot completely replace the benefits of in-person consultations.

Spectroscopic ellipsometry for analysis of polycrystalline thin-film photovoltaic devices and prediction of external quantum efficiency

NASA Astrophysics Data System (ADS)

Ibdah, Abdel-Rahman; Koirala, Prakash; Aryal, Puruswottam; Pradhan, Puja; Marsillac, Sylvain; Rockett, Angus A.; Podraza, Nikolas J.; Collins, Robert W.

2017-11-01

Complete polycrystalline thin-film photovoltaic (PV) devices employing CuIn1-xGaxSe2/CdS and CdS/CdTe heterojunctions have been studied by ex situ spectroscopic ellipsometry (SE). In this study, layer thicknesses have been extracted along with photon energy independent parameters such as compositions that describe the dielectric function spectra ε(E) of the individual layers. For accurate ex situ SE analysis of these PV devices, a database of ε(E) spectra is required for all thin film component materials used in each of the two absorber technologies. When possible, database measurements are performed by applying SE in situ immediately after deposition of the thin film materials and after cooling to room temperature in order to avoid oxidation and surface contamination. Determination of ε(E) from the resulting in situ SE data requires structural information that can be obtained from analysis of SE data acquired in real time during the deposition process. From the results of ex situ analysis of the complete CuIn1-xGaxSe2 (CIGS) and CdTe PV devices, the deduced layer thicknesses in combination with the parameters describing ε(E) can be employed in further studies that simulate the external quantum efficiency (EQE) spectra of the devices. These simulations have been performed here by assuming that all electron-hole pairs generated within the active layers, i.e. layers incorporating a dominant absorber component (either CIGS or CdTe), are separated and collected. The active layers may include not only the bulk absorber but also window and back contact interface layers, and individual current contributions from these layers have been determined in the simulations. In addition, the ex situ SE analysis results enable calculation of the absorbance spectra for the inactive layers and the overall reflectance spectra, which lead to quantification of all optical losses in terms of a current density deficit. Mapping SE can be performed given the high speed of multichannel ellipsometers employing array detection, and the resulting EQE simulation capability has wide applications in predicting large area PV module output. The ultimate goal is an on-line capability that enables prediction of PV sub-cell current output as early as possible in the production process.

Waveguide-based electro-absorption modulator performance: comparative analysis

NASA Astrophysics Data System (ADS)

Amin, Rubab; Khurgin, Jacob B.; Sorger, Volker J.

2018-06-01

Electro-optic modulation is a key function for data communication. Given the vast amount of data handled, understanding the intricate physics and trade-offs of modulators on-chip allows revealing performance regimes not explored yet. Here we show a holistic performance analysis for waveguide-based electro-absorption modulators. Our approach centers around material properties revealing obtainable optical absorption leading to effective modal cross-section, and material broadening effects. Taken together both describe the modulator physical behavior entirely. We consider a plurality of material modulation classes to include two-level absorbers such as quantum dots, free carrier accumulation or depletion such as ITO or Silicon, two-dimensional electron gas in semiconductors such as quantum wells, Pauli blocking in Graphene, and excitons in two-dimensional atomic layered materials such as found in transition metal dichalcogendies. Our results show that reducing the modal area generally improves modulator performance defined by the amount of induced electrical charge, and hence the energy-per-bit function, required switching the signal. We find that broadening increases the amount of switching charge needed. While some material classes allow for reduced broadening such as quantum dots and 2-dimensional materials due to their reduced Coulomb screening leading to increased oscillator strengths, the sharpness of broadening is overshadowed by thermal effects independent of the material class. Further we find that plasmonics allows the switching charge and energy-per-bit function to be reduced by about one order of magnitude compared to bulk photonics. This analysis is aimed as a guide for the community to predict anticipated modulator performance based on both existing and emerging materials.

Traveling wave solution of driven nonlinear Schrödinger equation

NASA Astrophysics Data System (ADS)

Akbari-Moghanjoughi, M.

2017-09-01

The traveling solitary and cnoidal wave solutions of the one dimensional driven nonlinear Schrödinger equation with a generalized form of nonlinearity are presented in this paper. We examine the modulation of nonlinear solitary excitations in two known weakly nonlinear models of classic oscillators, namely, the Helmholtz and Duffing oscillators and envelope structure formations for different oscillator and driver parameters. It is shown that two distinct regimes of subcritical and supercritical modulations may occur for nonlinear excitations with propagation speeds v <√{4 F0 } and v >√{4 F0 } , respectively, in which F0 is the driver force strength. The envelope soliton and cnoidal waves in these regimes are observed to be fundamentally different. The effect of pseudoenergy on the structure of the modulated envelope excitations is studied in detail for both sub- and supercritical modulation types. The current model for traveling envelope excitations may be easily extended to pseudopotentials with full nonlinearity relevant to more realistic gases, fluids, and plasmas.

Functional Module Analysis for Gene Coexpression Networks with Network Integration.

PubMed

Zhang, Shuqin; Zhao, Hongyu; Ng, Michael K

2015-01-01

Network has been a general tool for studying the complex interactions between different genes, proteins, and other small molecules. Module as a fundamental property of many biological networks has been widely studied and many computational methods have been proposed to identify the modules in an individual network. However, in many cases, a single network is insufficient for module analysis due to the noise in the data or the tuning of parameters when building the biological network. The availability of a large amount of biological networks makes network integration study possible. By integrating such networks, more informative modules for some specific disease can be derived from the networks constructed from different tissues, and consistent factors for different diseases can be inferred. In this paper, we have developed an effective method for module identification from multiple networks under different conditions. The problem is formulated as an optimization model, which combines the module identification in each individual network and alignment of the modules from different networks together. An approximation algorithm based on eigenvector computation is proposed. Our method outperforms the existing methods, especially when the underlying modules in multiple networks are different in simulation studies. We also applied our method to two groups of gene coexpression networks for humans, which include one for three different cancers, and one for three tissues from the morbidly obese patients. We identified 13 modules with three complete subgraphs, and 11 modules with two complete subgraphs, respectively. The modules were validated through Gene Ontology enrichment and KEGG pathway enrichment analysis. We also showed that the main functions of most modules for the corresponding disease have been addressed by other researchers, which may provide the theoretical basis for further studying the modules experimentally.

Tomography: Three Dimensional Image Construction. Applications of Analysis to Medical Radiology. [and] Genetic Counseling. Applications of Probability to Medicine. [and] The Design of Honeycombs. Applications of Differential Equations to Biology. Modules and Monographs in Undergraduate Mathematics and Its Applications Project. UMAP Units 318, 456, 502.

ERIC Educational Resources Information Center

Solomon, Frederick; And Others.

This document consists of three modules. The first looks at applications of analysis to medical radiology. The goals are to provide: 1) acquaintance with a significant applied mathematics problem utilizing Fourier Transforms; 2) generalization of the Fourier Transforms to two dimensions; 3) practice with Fourier Transforms; and 4) introduction to…

The investigation of bandwidth efficient coding and modulation techniques

NASA Technical Reports Server (NTRS)

1992-01-01

The New Mexico State University Center for Space Telemetering and Telecommunications systems has been, and is currently, engaged in the investigation of trellis-coded modulation (TCM) communication systems. In particular, TCM utilizing M-ary phase shift keying is being studied. The study of carrier synchronization in a TCM environment, or in MPSK systems in general, has been one of the two main thrusts of this grant. This study has involved both theoretical modelling and software simulation of the carrier synchronization problem.

Coherent control of double deflected anomalous modes in ultrathin trapezoid-shaped slit metasurface.

PubMed

Zhu, Z; Liu, H; Wang, D; Li, Y X; Guan, C Y; Zhang, H; Shi, J H

2016-11-22

Coherent light-matter interaction in ultrathin metamaterials has been demonstrated to dynamically modulate intensity, polarization and propagation direction of light. The gradient metasurface with a transverse phase variation usually exhibits an anomalous refracted beam of light dictated by so-called generalized Snell's law. However, less attention has been paid to coherent control of the metasurface with multiple anomalous refracted beams. Here we propose an ultrathin gradient metasurface with single trapezoid-shaped slot antenna as its building block that allows one normal and two deflected transmitted beams. It is numerically demonstrated that such metasurface with multiple scattering modes can be coherently controlled to modulate output intensities by changing the relative phase difference between two counterpropagating coherent beams. Each mode can be coherently switched on/off and two deflected anomalous beams can be synchronously dictated by the phase difference. The coherent control effect in the trapezoid-shaped slit metasurface will offer a promising opportunity for multichannel signals modulation, multichannel sensing and wave front shaping.

Coherent control of double deflected anomalous modes in ultrathin trapezoid-shaped slit metasurface

PubMed Central

Zhu, Z.; Liu, H.; Wang, D.; Li, Y. X.; Guan, C. Y.; Zhang, H.; Shi, J. H.

2016-01-01

Coherent light-matter interaction in ultrathin metamaterials has been demonstrated to dynamically modulate intensity, polarization and propagation direction of light. The gradient metasurface with a transverse phase variation usually exhibits an anomalous refracted beam of light dictated by so-called generalized Snell’s law. However, less attention has been paid to coherent control of the metasurface with multiple anomalous refracted beams. Here we propose an ultrathin gradient metasurface with single trapezoid-shaped slot antenna as its building block that allows one normal and two deflected transmitted beams. It is numerically demonstrated that such metasurface with multiple scattering modes can be coherently controlled to modulate output intensities by changing the relative phase difference between two counterpropagating coherent beams. Each mode can be coherently switched on/off and two deflected anomalous beams can be synchronously dictated by the phase difference. The coherent control effect in the trapezoid-shaped slit metasurface will offer a promising opportunity for multichannel signals modulation, multichannel sensing and wave front shaping. PMID:27874053

Optical Diagnostics of Solution Crystal Growth

NASA Technical Reports Server (NTRS)

Kim, Yongkee; Reddy, B. R.; George, T. G.; Lal, R. B.

1996-01-01

Non-contact optical techniques such as, optical heterodyne, ellipsometry and interferometry, for real time in-situ monitoring of solution crystal growth are demonstrated. Optical heterodyne technique has the capability of measuring the growth rate as small as 1A/sec. In a typical Michelson interferometer set up, the crystal is illuminated by a Zeeman laser with frequency omega(sub 1) and the reference beam with frequency omega(sub 2). As the crystal grows, the phase of the rf signal changes with respect to the reference beam and this phase change is related to the crystal growth rate. This technique is demonstrated with two examples: (1) by measuring the copper tip expansion/shrinkage rate and (2) by measuring the crystal growth rate of L-Arginine Phosphate (LAP). The first test shows that the expansion/shrinkage rate of copper tip was fast in the beginning, and gets slower as the expansion begins to stabilize with time. In crystal growth, the phase change due the crystal growth is measured using a phase meter and a strip chart recorder. Our experimental results indicate a varied growth rate from 69.4 to 92.6A per sec. The ellipsometer is used to study the crystal growth interface. From these measurements and a theoretical modeling of the interface, the various optical parameters can be deduced. Interferometry can also be used to measure the growth rate and concentration gradient in the vicinity of the crystal.

Study on deposition of Al2O3 films by plasma-assisted atomic layer with different plasma sources

NASA Astrophysics Data System (ADS)

Haiying, WEI; Hongge, GUO; Lijun, SANG; Xingcun, LI; Qiang, CHEN

2018-04-01

In this paper, Al2O3 thin films are deposited on a hydrogen-terminated Si substrate by using two home-built electron cyclotron resonance (ECR) and magnetic field enhanced radio frequency plasma-assisted atomic layer deposition (PA-ALD) devices with Al(CH3)3 (trimethylaluminum, TMA) and oxygen plasma used as precursor and oxidant, respectively. The thickness, chemical composition, surface morphology and group reactions are characterized by in situ spectroscopic ellipsometer, x-ray photoelectric spectroscopy, atomic force microscopy, scanning electron microscopy, a high-resolution transmission electron microscope and in situ mass spectrometry (MS), respectively. We obtain that both ECR PA-ALD and the magnetic field enhanced PA-ALD can deposit thin films with high density, high purity, and uniformity at a high deposition rate. MS analysis reveals that the Al2O3 deposition reactions are not simple reactions between TMA and oxygen plasma to produce alumina, water and carbon dioxide. In fact, acetylene, carbon monoxide and some other by-products also appear in the exhaustion gas. In addition, the presence of bias voltage has a certain effect on the deposition rate and surface morphology of films, which may be attributed to the presence of bias voltage controlling the plasma energy and density. We conclude that both plasma sources have a different deposition mechanism, which is much more complicated than expected.

Biotechnology Facility (BTF) for ISS

NASA Technical Reports Server (NTRS)

1998-01-01

Engineering mockup shows the general arrangement of the plarned Biotechnology Facility inside an EXPRESS rack aboard the International Space Station. This layout includes a gas supply module (bottom left), control computer and laptop interface (bottom right), two rotating wall vessels (top right), and support systems.

Working memory capacity and visual-verbal cognitive load modulate auditory-sensory gating in the brainstem: toward a unified view of attention.

PubMed

Sörqvist, Patrik; Stenfelt, Stefan; Rönnberg, Jerker

2012-11-01

Two fundamental research questions have driven attention research in the past: One concerns whether selection of relevant information among competing, irrelevant, information takes place at an early or at a late processing stage; the other concerns whether the capacity of attention is limited by a central, domain-general pool of resources or by independent, modality-specific pools. In this article, we contribute to these debates by showing that the auditory-evoked brainstem response (an early stage of auditory processing) to task-irrelevant sound decreases as a function of central working memory load (manipulated with a visual-verbal version of the n-back task). Furthermore, individual differences in central/domain-general working memory capacity modulated the magnitude of the auditory-evoked brainstem response, but only in the high working memory load condition. The results support a unified view of attention whereby the capacity of a late/central mechanism (working memory) modulates early precortical sensory processing.

Examining uptake of online education on obstructive sleep apnoea in general practitioners: a randomised trial.

PubMed

Paul, Christine; Rose, Shiho; Hensley, Michael; Pretto, Jeffrey; Hardy, Margaret; Henskens, Frans; Clinton-McHarg, Tara; Carey, Mariko

2016-07-19

Obstructive sleep apnoea (OSA) affects up to 28 % of the adult population in Western countries. The detection and management of OSA by general practitioners (GPs) can be poor. The study aimed to examine what influence enhanced invitations had on uptake of on-line learning modules for OSA by GPs, and whether recent referrals of patients to sleep specialists influenced uptake. Practicing GPs in regional Australia were identified and randomised to receive either an enhanced or standard invitation letter to a new on-line education module for OSA. The enhanced letter included indication that the module was eligible for professional accreditation and described the prevalence and burden of sleep disorders. Some included extra emphasis if the GP had recently referred a patient for diagnostic investigation of OSA. Two reminder letters were sent. Of 796 eligible GPs who received the letters, sixteen (2 %) accessed the website and four completed the modules over the four-month study period. GPs who received an enhanced invitation letter were not significantly more likely to access the website compared to GPs who received the standard invitation letter. Recent referral of a patient for diagnostic investigation was also not a significant factor in influencing use of the module. GP interest in on-line education about OSA appears low, and emphasis of relevant recent past patient(s) and the opportunity for professional education points was not successful in increasing engagement. There is a need to identify effective approaches to improving the detection and management of OSA in general practice.

Emotional modulation of pain and spinal nociception in fibromyalgia

PubMed Central

Rhudy, Jamie L.; DelVentura, Jennifer L.; Terry, Ellen L.; Bartley, Emily J.; Olech, Ewa; Palit, Shreela; Kerr, Kara L.

2013-01-01

Fibromyalgia (FM) is characterized by widespread pain, as well as affective disturbance (e.g., depression). Given that emotional processes are known to modulate pain, a disruption of emotion and emotional modulation of pain and nociception may contribute to FM. The present study used a well-validated affective picture-viewing paradigm to study emotional processing and emotional modulation of pain and spinal nociception. Participants were 18 individuals with FM, 18 individuals with rheumatoid arthritis (RA), and 19 healthy pain-free controls (HC). Mutilation, neutral, and erotic pictures were presented in four blocks; two blocks assessed only physiological-emotional reactions (i.e., pleasure/arousal ratings, corrugator EMG, startle modulation, skin conductance) in the absence of pain and two blocks assessed emotional reactivity and emotional modulation of pain and the nociceptive flexion reflex (NFR, a physiological measure of spinal nociception) evoked by suprathreshold electric stimulations over the sural nerve. In general, mutilation pictures elicited displeasure, corrugator activity, subjective arousal, and sympathetic activation, whereas erotic pictures elicited pleasure, subjective arousal, and sympathetic activation. However, FM was associated with deficits in appetitive activation (e.g., reduced pleasure/arousal to erotica). Moreover, emotional modulation of pain was observed in HC and RA, but not FM, even though all three groups evidenced modulation of NFR. Additionally, NFR thresholds were not lower in the FM group, indicating a lack of spinal sensitization. Together, these results suggest that FM is associated with a disruption of supraspinal processes associated with positive affect and emotional modulation of pain, but not brain-to-spinal cord circuitry that modulates spinal nociceptive processes. PMID:23622762

A common genetic variant in FOXP2 is associated with language-based learning (dis)abilities: Evidence from two Italian independent samples.

PubMed

Mozzi, Alessandra; Riva, Valentina; Forni, Diego; Sironi, Manuela; Marino, Cecilia; Molteni, Massimo; Riva, Stefania; Guerini, Franca R; Clerici, Mario; Cagliani, Rachele; Mascheretti, Sara

2017-04-24

Language-based Learning Disabilities (LLDs) encompass a group of complex, comorbid, and developmentally associated deficits in communication. Language impairment and developmental dyslexia (DD) represent the most recognized forms of LLDs. Substantial genetic correlations exist between language and reading (dis)abilities. Common variants in the FOXP2 gene were consistently associated with language- and reading-related neuropsychological and neuroanatomical phenotypes. We tested the effect of a FOXP2 common variant, that is, rs6980093 (A/G), on quantitative measures of language and reading in two independent Italian samples: a population-based cohort of 699 subjects (3-11 years old) and a sample of 572 children with DD (6-18 years old). rs6980093 modulates expressive language in the general population sample, with an effect on fluency scores. In the DD sample, the variant showed an association with the accuracy in the single word reading task. rs6980093 shows distinct genetic models of association in the two cohorts, with a dominant effect of the G allele in the general population sample and heterozygote advantage in the DD cohort. We provide preliminary evidence that rs6980093 associates with language and reading (dis)abilities in two independent Italian cohorts. rs6980093 is an intronic SNP, suggesting that it (or a linked variant) modulates phenotypic association via regulation of FOXP2 expression. Because FOXP2 brain expression is finely regulated, both temporally and spatially, it is possible that the two alleles at rs6980093 differentially modulate expression levels in a developmental stage- or brain area-specific manner. This might help explaining the heterozygote advantage effect and the different genetic models in the two cohorts. © 2017 Wiley Periodicals, Inc.

How sensitivity to ongoing interaural temporal disparities is affected by manipulations of temporal features of the envelopes of high-frequency stimuli

PubMed Central

Bernstein, Leslie R.; Trahiotis, Constantine

2009-01-01

This study addressed how manipulating certain aspects of the envelopes of high-frequency stimuli affects sensitivity to envelope-based interaural temporal disparities (ITDs). Listener’s threshold ITDs were measured using an adaptive two-alternative paradigm employing “raised-sine” stimuli [John, M. S., et al. (2002). Ear Hear. 23, 106–117] which permit independent variation in their modulation frequency, modulation depth, and modulation exponent. Threshold ITDs were measured while manipulating modulation exponent for stimuli having modulation frequencies between 32 and 256 Hz. The results indicated that graded increases in the exponent led to graded decreases in envelope-based threshold ITDs. Threshold ITDs were also measured while parametrically varying modulation exponent and modulation depth. Overall, threshold ITDs decreased with increases in the modulation depth. Unexpectedly, increases in the exponent of the raised-sine led to especially large decreases in threshold ITD when the modulation depth was low. An interaural correlation-based model was generally able to capture changes in threshold ITD stemming from changes in the exponent, depth of modulation, and frequency of modulation of the raised-sine stimuli. The model (and several variations of it), however, could not account for the unexpected interaction between the value of raised-sine exponent and its modulation depth. PMID:19425666

Joint Acoustic and Modulation Frequency

NASA Astrophysics Data System (ADS)

Atlas, Les; Shamma, Shihab A.

2003-12-01

There is a considerable evidence that our perception of sound uses important features which is related to underlying signal modulations. This topic has been studied extensively via perceptual experiments, yet there are few, if any, well-developed signal processing methods which capitalize on or model these effects. We begin by summarizing evidence of the importance of modulation representations from psychophysical, physiological, and other sources. The concept of a two-dimensional joint acoustic and modulation frequency representation is proposed. A simple single sinusoidal amplitude modulator of a sinusoidal carrier is then used to illustrate properties of an unconstrained and ideal joint representation. Added constraints are required to remove or reduce undesired interference terms and to provide invertibility. It is then noted that the constraints would also apply to more general and complex cases of broader modulation and carriers. Applications in single-channel speaker separation and in audio coding are used to illustrate the applicability of this joint representation. Other applications in signal analysis and filtering are suggested.

The issue of FM to AM conversion on the National Ignition Facility

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

Browning, D F; Rothenberg, J E; Wilcox, R B

1998-08-13

The National Ignition Facility (NIF) baseline configuration for inertial confinement fusion requires phase modulation for two purposes. First, ~ 1Å of frequency modulation (FM) bandwidth at low modulation frequency is required to suppress buildup of Stimulated Brioullin Scattering (SBS) in the large aperture laser optics. Also ~ 3 Å or more bandwidth at high modulation frequency is required for smoothing of the speckle pattern illuminating the target by the smoothing by spectral dispersion method (SSD). Ideally, imposition of bandwidth by pure phase modulation does not affect the beam intensity. However, as a result of a large number of effects, themore » FM converts to amplitude modulation (AM). In general this adversely affects the laser performance, e.g. by reducing the margin against damage to the optics. In particular, very large conversion of FM to AM has been observed in the NIF all-fiber master oscillator and distribution systems. The various mechanisms leading to AM are analyzed and approaches to minimizing their effects are discussed.« less

Teaching home safety and survival skills to latch-key children: a comparison of two manuals and methods.

PubMed Central

Peterson, L

1984-01-01

I evaluated the influence of two training manuals on latch-key children's acquisition of home safety and survival skills. The widely used, discussion-oriented "Prepared for Today" manual was compared with a behaviorally oriented "Safe at Home" manual. Data were scored by response criteria developed by experts and by parents' and experts' ratings of children's spontaneous answers. With both methods of scoring, three behaviorally trained children demonstrated clear and abrupt increases in skill following training in each of seven trained modules, and these increases largely persisted in real world generalization probes and at 5-month follow-up. Smaller and less stable increases in skill were found in the three discussion-trained children across the seven modules; lower skill levels were also seen in real world generalization probes and at follow-up. Neither group of children demonstrated skill increases in home safety areas that were not explicitly trained. Both training methods produced small decreases in children's self-report of general anxiety and anxiety concerning home safety. Results are discussed in terms of their implications for cost-effective training of latch-key children. PMID:6511698

The Dolinar Receiver in an Information Theoretic Framework

NASA Technical Reports Server (NTRS)

Erkmen, Baris I.; Birnbaum, Kevin M.; Moision, Bruce E.; Dolinar, Samuel J.

2011-01-01

Optical communication at the quantum limit requires that measurements on the optical field be maximally informative, but devising physical measurements that accomplish this objective has proven challenging. The Dolinar receiver exemplifies a rare instance of success in distinguishing between two coherent states: an adaptive local oscillator is mixed with the signal prior to photodetection, which yields an error probability that meets the Helstrom lower bound with equality. Here we apply the same local-oscillator-based architecture with aninformation-theoretic optimization criterion. We begin with analysis of this receiver in a general framework for an arbitrary coherent-state modulation alphabet, and then we concentrate on two relevant examples. First, we study a binary antipodal alphabet and show that the Dolinar receiver's feedback function not only minimizes the probability of error, but also maximizes the mutual information. Next, we study ternary modulation consistingof antipodal coherent states and the vacuum state. We derive an analytic expression for a near-optimal local oscillator feedback function, and, via simulation, we determine its photon information efficiency (PIE). We provide the PIE versus dimensional information efficiency (DIE) trade-off curve and show that this modulation and the our receiver combination performs universally better than (generalized) on-off keying plus photoncounting, although, the advantage asymptotically vanishes as the bits-per-photon diverges towards infinity.

Evolution of functional specialization and division of labor.

PubMed

Rueffler, Claus; Hermisson, Joachim; Wagner, Günter P

2012-02-07

Division of labor among functionally specialized modules occurs at all levels of biological organization in both animals and plants. Well-known examples include the evolution of specialized enzymes after gene duplication, the evolution of specialized cell types, limb diversification in arthropods, and the evolution of specialized colony members in many taxa of marine invertebrates and social insects. Here, we identify conditions favoring the evolution of division of labor by means of a general mathematical model. Our starting point is the assumption that modules contribute to two different biological tasks and that the potential of modules to contribute to these tasks is traded off. Our results are phrased in terms of properties of performance functions that map the phenotype of modules to measures of performance. We show that division of labor is favored by three factors: positional effects that predispose modules for one of the tasks, accelerating performance functions, and synergistic interactions between modules. If modules can be lost or damaged, selection for robustness can counteract selection for functional specialization. To illustrate our theory we apply it to the evolution of specialized enzymes coded by duplicated genes.

Quantitative and qualitative microbiological profiles of the Apollo 10 and 11 spacecraft.

PubMed

Puleo, J R; Oxborrow, G S; Fields, N D; Hall, H E

1970-09-01

Microbiological profiles were determined for surfaces of the command module, lunar module (ascent and descent stages), instrument unit, Saturn S-4B stage, and the spacecraft lunar module adapter of the Apollo 10 and 11 spacecraft. Average levels of contamination of the command module were 2.1 x 10(4) and 2.7 x 10(4) microorganisms per ft(2) for Apollo 10 and 11, respectively. With the exception of the exterior surfaces of the ascent stage of the lunar module and the interior surfaces of the command module, average levels of microbial contamination on all components of the Apollo 11 were found to be lower than those observed on Apollo 10. For each Apollo mission, approximately 2,000 colonies were picked from a variety of media and identified. The results showed that approximately 95% of all isolates were those considered indigenous to humans; the remaining were associated with soil and dust in the environment. However, the ratio of these two general groups varied depending on the degrees of personnel density and environmental control associated with each module.

Planetary period modulations of Saturn's magnetotail current sheet during northern spring: Observations and modeling

NASA Astrophysics Data System (ADS)

Cowley, S. W. H.; Provan, G.

2017-06-01

We study Cassini magnetic field observations at Saturn on a sequence of passes through the near-equatorial magnetotail during 2015, focusing on dual modulation of the plasma/current sheet associated with northern and southern planetary period oscillations (PPOs). Previous study of inner magnetosphere PPOs during this northern spring interval showed that the southern system amplitude was generally half that of the northern during the first part of the year to late August, after which the southern amplitude weakened to less than one-fifth that of the northern. We examine four sequential tail passes in the earlier interval, during which prominent PPO-related tail field modulations were observed, with relative (beat) phases of the two PPO systems being near in phase, antiphase, and two opposite near-quadrature conditions. We find that the radial field displayed opposite "sawtooth" asymmetry modulations under opposite near-quadrature conditions, related to previous findings under equinoctial conditions with near-equal northern and southern PPO amplitudes, while modulations were near symmetric for in-phase and antiphase conditions, but with larger radial field modulations for in-phase and larger colatitudinal field modulations for antiphase. A simple physical mathematical model of dual modulation is developed, which provides reasonable correspondence with these data using one set of current sheet parameters while varying only the relative PPO phases, thus demonstrating that dual modulation can be discerned and modeled even when the northern and southern amplitudes differ by a factor of 2. No such effects were consistently discerned during the later interval when the amplitude ratio was >5.

A unified heteronuclear decoupling strategy for magic-angle-spinning solid-state NMR spectroscopy

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

Equbal, Asif; Bjerring, Morten; Nielsen, Niels Chr., E-mail: madhu@tifr.res.in, E-mail: ncn@inano.au.dk

2015-05-14

A unified strategy of two-pulse based heteronuclear decoupling for solid-state magic-angle spinning nuclear magnetic resonance is presented. The analysis presented here shows that different decoupling sequences like two-pulse phase-modulation (TPPM), X-inverse-X (XiX), and finite pulse refocused continuous wave (rCW{sup A}) are basically specific solutions of a more generalized decoupling scheme which incorporates the concept of time-modulation along with phase-modulation. A plethora of other good decoupling conditions apart from the standard, TPPM, XiX, and rCW{sup A} decoupling conditions are available from the unified decoupling approach. The importance of combined time- and phase-modulation in order to achieve the best decoupling conditions ismore » delineated. The consequences of different indirect dipolar interactions arising from cross terms comprising of heteronuclear and homonuclear dipolar coupling terms and also those between heteronuclear dipolar coupling and chemical-shift anisotropy terms are presented in order to unfold the effects of anisotropic interactions under different decoupling conditions. Extensive numerical simulation results are corroborated with experiments on standard amino acids.« less

Use of control umbilicals as a deployment mode for free flying telerobotic work systems

NASA Technical Reports Server (NTRS)

Kuehn, J. S.; Selle, E. D.

1987-01-01

Work to date on telerobotic work systems for use in space generally consider two deployment modes, free flying, or fixed within a limited work envelope. Control tethers may be employed to obtain a number of operational advantages and added flexibility in the basing and deployment of telerobotic work systems. Use of a tether allows the work system to be separated into two major modules, the remote work package and the control module. The Remote Work Package (RWP) comprises the free flying portion of the work system while the Control Module (CM) remains at the work system base. The chief advantage of this configuration is that only the components required for completion of the work task must be located at the work site. Reaction mass used in free flight is stored at the Control module and supplied to the RWP through the tether, eliminating the need for the RWP to carry it. The RWP can be made less massive than a self contained free flying work system. As a result, reaction mass required for free flight is lower than for a self contained free flyer.

Atom optics in the time domain

NASA Astrophysics Data System (ADS)

Arndt, M.; Szriftgiser, P.; Dalibard, J.; Steane, A. M.

1996-05-01

Atom-optics experiments are presented using a time-modulated evanescent light wave as an atomic mirror in the trampoline configuration, i.e., perpendicular to the direction of the atomic free fall. This modulated mirror is used to accelerate cesium atoms, to focus their trajectories, and to apply a ``multiple lens'' to separately focus different velocity classes of atoms originating from a point source. We form images of a simple two-slit object to show the resolution of the device. The experiments are modelled by a general treatment analogous to classical ray optics.

Gordan—Capelli series in superalgebras

PubMed Central

Brini, Andrea; Palareti, Aldopaolo; Teolis, Antonio G. B.

1988-01-01

We derive two Gordan—Capelli series for the supersymmetric algebra of the tensor product of two [unk]2-graded [unk]-vector spaces U and V, being [unk] a field of characteristic zero. These expansions yield complete decompositions of the supersymmetric algebra regarded as a pl(U)- and a pl(V)- module, where pl(U) and pl(V) are the general linear Lie superalgebras of U and V, respectively. PMID:16593911

Ellipsometric study of Al2O3/Ag/Si and SiO2/Ag/quartz ashed in an oxygen plasma. [protective coatings to prevent degradation of materials in low earth orbits

NASA Technical Reports Server (NTRS)

De, Bhola N.; Woollam, John A.

1989-01-01

The growth of silver oxide (proposed as a potentially useful protective coating for space environment) on a silver mirror coated with an Al2O3 or a SiO2 protective layer was investigated using the monolayer-sensitive variable angle of incidence spectroscopic ellipsometry technique. The samples were exposed to a pure oxygen plasma in a plasma asher, and the silver oxide growth was monitored as a function of the exposure time. It was found that atomic oxygen in the asher penetrated through the SiO2 or Al2O3 coatings to convert the silver underneath to silver oxide, and that the quantity of the silver oxide formed was proportional to the ashing time. The band gap of silver oxide was determined to be 1.3 eV. A schematic diagram of the variable angle of incidence spectroscopic ellipsometer is included.

Deep and tapered silicon photonic crystals for achieving anti-reflection and enhanced absorption.

PubMed

Hung, Yung-Jr; Lee, San-Liang; Coldren, Larry A

2010-03-29

Tapered silicon photonic crystals (PhCs) with smooth sidewalls are realized using a novel single-step deep reactive ion etching. The PhCs can significantly reduce the surface reflection over the wavelength range between the ultra-violet and near-infrared regions. From the measurements using a spectrophotometer and an angle-variable spectroscopic ellipsometer, the sub-wavelength periodic structure can provide a broad and angular-independent antireflective window in the visible region for the TE-polarized light. The PhCs with tapered rods can further reduce the reflection due to a gradually changed effective index. On the other hand, strong optical resonances for TM-mode can be found in this structure, which is mainly due to the existence of full photonic bandgaps inside the material. Such resonance can enhance the optical absorption inside the silicon PhCs due to its increased optical paths. With the help of both antireflective and absorption-enhanced characteristics in this structure, the PhCs can be used for various applications.

Structural and optical study of tellurite-barium glasses

NASA Astrophysics Data System (ADS)

Grelowska, I.; Reben, M.; Burtan, B.; Sitarz, M.; Cisowski, J.; Yousef, El Sayed; Knapik, A.; Dudek, M.

2016-12-01

The goal of this work was to determine the effect of barium oxide on the structural, thermal and optical properties of the TeO2-BaO-Na2O (TBN) and TeO2-BaO-WO3 (TBW) glass systems. Raman spectra allow relating the glass structure and vibration properties (i.e. vibrational frequencies and Raman intensities) with the glass composition. Raman spectra show the presence of TeO4 and TeO3+1/TeO3 units that conform with the glass matrix. Differential thermal analysis DTA, XRD measurements have been considered in term of BaO addition. The spectral dependence of ellipsometric angles of the tellurite-barium glass has been studied. The optical measurements were conducted on Woollam M2000 spectroscopic ellipsometer in spectral range of 190-1700 nm. The reflectance and transmittance measurements have been done on spectrophotometer Perkin Elmer, Lambda 900 in the range of 200-2500 nm (UV-VIS-NIR). From the transmittance spectrum, the energy gap was determined.

The effect of learning via module versus lecture teaching methods on the knowledge and practice of oncology nurses about safety standards with cytotoxic drugs in Shiraz University of Medical Sciences.

PubMed

Abbasi, Khadijeh; Hazrati, Maryam; Mohamadi, Nasrin Pourali; Rajaeefard, Abdolreza

2013-11-01

Several studies have established that all nurses need continuing education, especially those who are working in oncology wards. In the current programs, there are just two general patterns for teaching: Teacher-centered and student-centered patterns. In this study, the effect of teacher-centered (lecture) and student-centered (module) teaching methods in relation to safety standards with cytotoxic drugs on the knowledge and practice of oncology nurses was compared. This research was a quasi-experimental study with two intervention groups (module and lecture) and a control group. In this study, 86 nurses in Shiraz, Fars province in 2011, who participated in the prescription of cytotoxic drugs to patients were selected and randomly divided into three groups. The module group used a self-directed module, the lecture group was taught by an experienced lecturer in the classroom and the control group did not receive any intervention. Data in relation to knowledge and practice of oncology nurses in the three groups were collected before and 8 weeks after the intervention by using a questionnaire and checklist. To analyze the data paired-samples t-test and one way ANOVA analysis were used. Knowledge and practice scores increased significantly from baseline in both intervention groups, but there was no significant difference between the scores of the two groups. No considerable changes were observed in the control group. Both module and lecture methods have similar effects on improving the knowledge and practice of nurses in oncology wards. Therefore, considering the advantages of student-centered educational methods, the work load of nurses and the sensitivity of their jobs, we suggest using module.

Cerebellar output controls generalized spike‐and‐wave discharge occurrence

PubMed Central

Kros, Lieke; Eelkman Rooda, Oscar H. J.; Spanke, Jochen K.; Alva, Parimala; van Dongen, Marijn N.; Karapatis, Athanasios; Tolner, Else A.; Strydis, Christos; Davey, Neil; Winkelman, Beerend H. J.; Negrello, Mario; Serdijn, Wouter A.; Steuber, Volker; van den Maagdenberg, Arn M. J. M.; De Zeeuw, Chris I.

2015-01-01

Objective Disrupting thalamocortical activity patterns has proven to be a promising approach to stop generalized spike‐and‐wave discharges (GSWDs) characteristic of absence seizures. Here, we investigated to what extent modulation of neuronal firing in cerebellar nuclei (CN), which are anatomically in an advantageous position to disrupt cortical oscillations through their innervation of a wide variety of thalamic nuclei, is effective in controlling absence seizures. Methods Two unrelated mouse models of generalized absence seizures were used: the natural mutant tottering, which is characterized by a missense mutation in Cacna1a, and inbred C3H/HeOuJ. While simultaneously recording single CN neuron activity and electrocorticogram in awake animals, we investigated to what extent pharmacologically increased or decreased CN neuron activity could modulate GSWD occurrence as well as short‐lasting, on‐demand CN stimulation could disrupt epileptic seizures. Results We found that a subset of CN neurons show phase‐locked oscillatory firing during GSWDs and that manipulating this activity modulates GSWD occurrence. Inhibiting CN neuron action potential firing by local application of the γ‐aminobutyric acid type A (GABA‐A) agonist muscimol increased GSWD occurrence up to 37‐fold, whereas increasing the frequency and regularity of CN neuron firing with the use of GABA‐A antagonist gabazine decimated its occurrence. A single short‐lasting (30–300 milliseconds) optogenetic stimulation of CN neuron activity abruptly stopped GSWDs, even when applied unilaterally. Using a closed‐loop system, GSWDs were detected and stopped within 500 milliseconds. Interpretation CN neurons are potent modulators of pathological oscillations in thalamocortical network activity during absence seizures, and their potential therapeutic benefit for controlling other types of generalized epilepsies should be evaluated. Ann Neurol 2015;77:1027–1049 PMID:25762286

Heterogeneity of Purkinje cell simple spike-complex spike interactions: zebrin- and non-zebrin-related variations.

PubMed

Tang, Tianyu; Xiao, Jianqiang; Suh, Colleen Y; Burroughs, Amelia; Cerminara, Nadia L; Jia, Linjia; Marshall, Sarah P; Wise, Andrew K; Apps, Richard; Sugihara, Izumi; Lang, Eric J

2017-08-01

Cerebellar Purkinje cells (PCs) generate two types of action potentials, simple and complex spikes. Although they are generated by distinct mechanisms, interactions between the two spike types exist. Zebrin staining produces alternating positive and negative stripes of PCs across most of the cerebellar cortex. Thus, here we compared simple spike-complex spike interactions both within and across zebrin populations. Simple spike activity undergoes a complex modulation preceding and following a complex spike. The amplitudes of the pre- and post-complex spike modulation phases were correlated across PCs. On average, the modulation was larger for PCs in zebrin positive regions. Correlations between aspects of the complex spike waveform and simple spike activity were found, some of which varied between zebrin positive and negative PCs. The implications of the results are discussed with regard to hypotheses that complex spikes are triggered by rises in simple spike activity for either motor learning or homeostatic functions. Purkinje cells (PCs) generate two types of action potentials, called simple and complex spikes (SSs and CSs). We first investigated the CS-associated modulation of SS activity and its relationship to the zebrin status of the PC. The modulation pattern consisted of a pre-CS rise in SS activity, and then, following the CS, a pause, a rebound, and finally a late inhibition of SS activity for both zebrin positive (Z+) and negative (Z-) cells, though the amplitudes of the phases were larger in Z+ cells. Moreover, the amplitudes of the pre-CS rise with the late inhibitory phase of the modulation were correlated across PCs. In contrast, correlations between modulation phases across CSs of individual PCs were generally weak. Next, the relationship between CS spikelets and SS activity was investigated. The number of spikelets/CS correlated with the average SS firing rate only for Z+ cells. In contrast, correlations across CSs between spikelet numbers and the amplitudes of the SS modulation phases were generally weak. Division of spikelets into likely axonally propagated and non-propagated groups (based on their interspikelet interval) showed that the correlation of spikelet number with SS firing rate primarily reflected a relationship with non-propagated spikelets. In sum, the results show both zebrin-related and non-zebrin-related physiological heterogeneity in SS-CS interactions among PCs, which suggests that the cerebellar cortex is more functionally diverse than is assumed by standard theories of cerebellar function. © 2017 The Authors. The Journal of Physiology © 2017 The Physiological Society.

Comparison of Grammar in Neurodevelopmental Disorders: The Case of Binding in Williams Syndrome and Autism With and Without Language Impairment

PubMed Central

Modyanova, Nadya; Wexler, Ken

2013-01-01

This study investigates whether distinct neurodevelopmental disorders show distinct patterns of impairments in particular grammatical abilities and the relation of those grammatical patterns to general language delays and intellectual disabilities. We studied two disorders (autism and Williams syndrome [WS]) and two distinct properties (Principle A that governs reflexives and Principle B that, together with its associated pragmatic rule, governs pronouns) of the binding module of grammar. These properties are known to have markedly different courses of acquisition in typical development. We compare the knowledge of binding in children with autism with language impairment (ALI) and those with normal language (ALN) to that of children with WS, matched on age to the ALN group, and on age and nonverbal mental age (MA) to the ALI group, as well as to two groups of typically developing (TD) controls, matched on nonverbal MA to ALI and ALN groups. Our results reveal a remarkably different pattern of comprehension of personal pronouns and reflexives in ALI as opposed to ALN, WS, and two groups of TD controls. All five groups demonstrated an equal delay in their comprehension of personal pronouns, in line with widely reported delays in TD literature, argued to be due to delayed pragmatic abilities. However, and most strikingly, the ALI group also showed a pronounced difficulty in comprehension of reflexive pronouns, and particularly of the knowledge that the antecedent of a reflexive must c-command it. The revealed pattern confirms the existence of a particular impairment concerning Principle A in this module of grammar, unrelated to general language delays or cognitive deficits generally present in a large portion of individuals with autism as well as WS, or to general pragmatic deficits, known to be particularly prevalent in the population with autism. PMID:25170241

The flare origin of Forbush decreases not associated with solar flares on the visible hemisphere of the Sun

NASA Technical Reports Server (NTRS)

Iucci, N.; Parisi, M.; Signorini, C.; Storini, M.; Villoresi, G.

1985-01-01

Investigations have shown that Forbush decreases (Fds) are produced by the propagation into the interplanetary space of a strong perturbation originating from a solar flare (Sf) accompanied by Type IV radioemission. As the front of the perturbation propagates into the interplanetary space, the region in which the galactic cosmic rays are modulated (Fd-modulated region) rotates westward with the Sun and is generally included between two boundary streams; therefore the Fds not associated with observed type IV Sfs (N.Ass.Fds) are likely to be produced by type IV Sfs occurred on the Sun's backside: these vents can be observed when the Earth crosses the corotating Western boundary of the modulated region.

The flare origin of Forbush decreases not associated with solar flares on the visible hemisphere of the Sun

NASA Astrophysics Data System (ADS)

Iucci, N.; Parisi, M.; Signorini, C.; Storini, M.; Villoresi, G.

1985-08-01

Investigations have shown that Forbush decreases (Fds) are produced by the propagation into the interplanetary space of a strong perturbation originating from a solar flare (Sf) accompanied by Type IV radioemission. As the front of the perturbation propagates into the interplanetary space, the region in which the galactic cosmic rays are modulated (Fd-modulated region) rotates westward with the Sun and is generally included between two boundary streams; therefore the Fds not associated with observed type IV Sfs (N.Ass.Fds) are likely to be produced by type IV Sfs occurred on the Sun's backside: these vents can be observed when the Earth crosses the corotating Western boundary of the modulated region.

Optimization of storage tank locations in an urban stormwater drainage system using a two-stage approach.

PubMed

Wang, Mingming; Sun, Yuanxiang; Sweetapple, Chris

2017-12-15

Storage is important for flood mitigation and non-point source pollution control. However, to seek a cost-effective design scheme for storage tanks is very complex. This paper presents a two-stage optimization framework to find an optimal scheme for storage tanks using storm water management model (SWMM). The objectives are to minimize flooding, total suspended solids (TSS) load and storage cost. The framework includes two modules: (i) the analytical module, which evaluates and ranks the flooding nodes with the analytic hierarchy process (AHP) using two indicators (flood depth and flood duration), and then obtains the preliminary scheme by calculating two efficiency indicators (flood reduction efficiency and TSS reduction efficiency); (ii) the iteration module, which obtains an optimal scheme using a generalized pattern search (GPS) method based on the preliminary scheme generated by the analytical module. The proposed approach was applied to a catchment in CZ city, China, to test its capability in choosing design alternatives. Different rainfall scenarios are considered to test its robustness. The results demonstrate that the optimal framework is feasible, and the optimization is fast based on the preliminary scheme. The optimized scheme is better than the preliminary scheme for reducing runoff and pollutant loads under a given storage cost. The multi-objective optimization framework presented in this paper may be useful in finding the best scheme of storage tanks or low impact development (LID) controls. Copyright © 2017 Elsevier Ltd. All rights reserved.

Fully interferometric controllable anomalous refraction efficiency using cross modulation with plasmonic metasurfaces.

PubMed

Liu, Zhaocheng; Chen, Shuqi; Li, Jianxiong; Cheng, Hua; Li, Zhancheng; Liu, Wenwei; Yu, Ping; Xia, Ji; Tian, Jianguo

2014-12-01

We present a method of fully interferometric, controllable anomalous refraction efficiency by introducing cross-modulated incident light based on plasmonic metasurfaces. Theoretical analyses and numerical simulations indicate that the anomalous and ordinary refracted beams generated from two opposite-helicity incident beams and following the generalized Snell's law will have a superposition for certain incident angles, and the anomalous refraction efficiency can be dynamically controlled by changing the relative phase of the incident sources. As the incident wavelength nears the resonant wavelength of the plasmonic metasurfaces, two equal-amplitude incident beams with opposite helicity can be used to control the anomalous refraction efficiency. Otherwise, two unequal-amplitude incident beams with opposite helicity can be used to fully control the anomalous refraction efficiency. This Letter may offer a further step in the development of controllable anomalous refraction.

Value-modulated oculomotor capture by task-irrelevant stimuli is a consequence of early competition on the saccade map.

PubMed

Pearson, Daniel; Osborn, Raphaella; Whitford, Thomas J; Failing, Michel; Theeuwes, Jan; Le Pelley, Mike E

2016-10-01

Recent research has shown that reward learning can modulate oculomotor and attentional capture by physically salient and task-irrelevant distractor stimuli, even when directing gaze to those stimuli is directly counterproductive to receiving reward. This value-modulated oculomotor capture effect may reflect biased competition in the oculomotor system, such that the relationship between a stimulus feature and reward enhances that feature's representation on an internal priority map. However, it is also possible that this effect is a result of reward reducing the threshold for a saccade to be made to salient items. Here, we demonstrate value-modulated oculomotor capture when two reward-associated distractor stimuli are presented simultaneously in the same search display. The influence of reward on oculomotor capture is found to be most prominent at the shortest saccade latencies. We conclude that the value-modulated oculomotor capture effect is a consequence of biased competition on the saccade priority map and cannot be explained by a general reduction in saccadic threshold.

Participation of Bell Telephone Laboratories in Project Echo and Experimental Results

NASA Technical Reports Server (NTRS)

Jakes, William C., Jr.

1961-01-01

On August 12, 1960, Echo I, a 100-foot-diameter spherical balloon, was placed in orbit around the earth by the National Aeronautics and Space Administration. The objective was to demonstrate the feasibility of long-distance communication by microwave reflection from a satellite. A two-way coast-to-coast voice circuit was to be established between the Jet Propulsion Laboratory (JPL) facility in California and a station provided by Bell Telephone Laboratories (STL) in New Jersey. Similar tests were also planned with the Naval Research Laboratory and other stations. This paper describes the general organization and operation of the Holmdel, New Jersey, station, and discusses the results of the experiments performed between the balloon launching and March 1, 1961. Successful voice communication was achieved through a variety of modulation methods including frequency modulation with feedback, amplitude modulation, single-sideband modulation, and narrow-band phase modulation. Careful measurements were also made of the loss in the transmission path.

Neutron transport analysis for nuclear reactor design

DOEpatents

Vujic, Jasmina L.

1993-01-01

Replacing regular mesh-dependent ray tracing modules in a collision/transfer probability (CTP) code with a ray tracing module based upon combinatorial geometry of a modified geometrical module (GMC) provides a general geometry transfer theory code in two dimensions (2D) for analyzing nuclear reactor design and control. The primary modification of the GMC module involves generation of a fixed inner frame and a rotating outer frame, where the inner frame contains all reactor regions of interest, e.g., part of a reactor assembly, an assembly, or several assemblies, and the outer frame, with a set of parallel equidistant rays (lines) attached to it, rotates around the inner frame. The modified GMC module allows for determining for each parallel ray (line), the intersections with zone boundaries, the path length between the intersections, the total number of zones on a track, the zone and medium numbers, and the intersections with the outer surface, which parameters may be used in the CTP code to calculate collision/transfer probability and cross-section values.

Neutron transport analysis for nuclear reactor design

DOEpatents

Vujic, J.L.

1993-11-30

Replacing regular mesh-dependent ray tracing modules in a collision/transfer probability (CTP) code with a ray tracing module based upon combinatorial geometry of a modified geometrical module (GMC) provides a general geometry transfer theory code in two dimensions (2D) for analyzing nuclear reactor design and control. The primary modification of the GMC module involves generation of a fixed inner frame and a rotating outer frame, where the inner frame contains all reactor regions of interest, e.g., part of a reactor assembly, an assembly, or several assemblies, and the outer frame, with a set of parallel equidistant rays (lines) attached to it, rotates around the inner frame. The modified GMC module allows for determining for each parallel ray (line), the intersections with zone boundaries, the path length between the intersections, the total number of zones on a track, the zone and medium numbers, and the intersections with the outer surface, which parameters may be used in the CTP code to calculate collision/transfer probability and cross-section values. 28 figures.

Periodically modulated single-photon transport in one-dimensional waveguide

NASA Astrophysics Data System (ADS)

Li, Xingmin; Wei, L. F.

2018-03-01

Single-photon transport along a one-dimension waveguide interacting with a quantum system (e.g., two-level atom) is a very useful and meaningful simplified model of the waveguide-based optical quantum devices. Thus, how to modulate the transport of the photons in the waveguide structures by adjusting certain external parameters should be particularly important. In this paper, we discuss how such a modulation could be implemented by periodically driving the energy splitting of the interacting atom and the atom-photon coupling strength. By generalizing the well developed time-independent full quantum mechanical theory in real space to the time-dependent one, we show that various sideband-transmission phenomena could be observed. This means that, with these modulations the photon has certain probabilities to transmit through the scattering atom in the other energy sidebands. Inversely, by controlling the sideband transmission the periodic modulations of the single photon waveguide devices could be designed for the future optical quantum information processing applications.

Computational Re-design of Synthetic Genetic Oscillators for Independent Amplitude and Frequency Modulation.

PubMed

Tomazou, Marios; Barahona, Mauricio; Polizzi, Karen M; Stan, Guy-Bart

2018-04-25

To perform well in biotechnology applications, synthetic genetic oscillators must be engineered to allow independent modulation of amplitude and period. This need is currently unmet. Here, we demonstrate computationally how two classic genetic oscillators, the dual-feedback oscillator and the repressilator, can be re-designed to provide independent control of amplitude and period and improve tunability-that is, a broad dynamic range of periods and amplitudes accessible through the input "dials." Our approach decouples frequency and amplitude modulation by incorporating an orthogonal "sink module" where the key molecular species are channeled for enzymatic degradation. This sink module maintains fast oscillation cycles while alleviating the translational coupling between the oscillator's transcription factors and output. We characterize the behavior of our re-designed oscillators over a broad range of physiologically reasonable parameters, explain why this facilitates broader function and control, and provide general design principles for building synthetic genetic oscillators that are more precisely controllable. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

Nonadiabatic effect on the quantum heat flux control.

PubMed

Uchiyama, Chikako

2014-05-01

We provide a general formula of quantum transfer that includes the nonadiabatic effect under periodic environmental modulation by using full counting statistics in Hilbert-Schmidt space. Applying the formula to an anharmonic junction model that interacts with two bosonic environments within the Markovian approximation, we find that the quantum transfer is divided into the adiabatic (dynamical and geometrical phases) and nonadiabatic contributions. This extension shows the dependence of quantum transfer on the initial condition of the anharmonic junction just before the modulation, as well as the characteristic environmental parameters such as interaction strength and cut-off frequency of spectral density. We show that the nonadiabatic contribution represents the reminiscent effect of past modulation including the transition from the initial condition of the anharmonic junction to a steady state determined by the very beginning of the modulation. This enables us to tune the frequency range of modulation, whereby we can obtain the quantum flux corresponding to the geometrical phase by setting the initial condition of the anharmonic junction.

Biomechanics and Biotensegrity: Study Method and Frequency Response of the Simplex and 3-bar-SVD Tensegrity Configurations

NASA Astrophysics Data System (ADS)

Castro Arenas, C.; Ghersi, I.; Miralles, M. T.

2016-04-01

The purpose of this work is to study the frequency response of 3D tensegrity structures. These are structures that have been used, since the 80’s, to model biological systems of different scales. This fact led to the origin of the field of biotensegrity, which includes biomechanics as a natural field of application. In this work: a) A simple method for the analysis of frequency response of different nodes in 3D tensegrity structures was set up and tuned. This method is based on a video-analysis algorithm, which was applied to the structures, as they were vibrated along their axis of symmetry, at frequencies from 1 Hz to 60 Hz. b) Frequency-response analyses were performed, for the simplest 3D structure, the Simplex module, as well as for two towers, formed by stacking two and three Simplex modules, respectively. Resonant frequencies were detected for the Simplex module at (19.2±0.1) Hz and (50.2±0.1) Hz (the latter being an average of frequencies between homologous nodes). For the towers with two and three modules, each selected node presented a characteristic frequency response, modulated by their spatial placement in each model. Resonances for the two-stage tower were found at: (12±0.1) Hz; (16.2±0.1) Hz; (29.4±0.1) Hz and (37.2±0.1) Hz. For the tower with three Simplex modules, the main resonant frequencies were found at (12.0±0.1) Hz and (21.0±0.1) Hz. Results show that the proposed method is adequate for the study (2D) of any 3D tensegrity structure, with the potential of being generalized to the study of oscillations in three dimensions. A growing complexity and variability in the frequency response of the nodes was observed, as modules were added to the structures. These findings were compared to those found in the available literature.

Generation of flat wideband chaos with suppressed time delay signature by using optical time lens.

PubMed

Jiang, Ning; Wang, Chao; Xue, Chenpeng; Li, Guilan; Lin, Shuqing; Qiu, Kun

2017-06-26

We propose a flat wideband chaos generation scheme that shows excellent time delay signature suppression effect, by injecting the chaotic output of general external cavity semiconductor laser into an optical time lens module composed of a phase modulator and two dispersive units. The numerical results demonstrate that by properly setting the parameters of the driving signal of phase modulator and the accumulated dispersion of dispersive units, the relaxation oscillation in chaos can be eliminated, wideband chaos generation with an efficient bandwidth up to several tens of GHz can be achieved, and the RF spectrum of generated chaotic signal is nearly as flat as uniform distribution. Moreover, the periodicity of chaos induced by the external cavity modes can be simultaneously destructed by the optical time lens module, based on this the time delay signature can be completely suppressed.

Multidimensional signaling via wavelet packets

NASA Astrophysics Data System (ADS)

Lindsey, Alan R.

1995-04-01

This work presents a generalized signaling strategy for orthogonally multiplexed communication. Wavelet packet modulation (WPM) employs the basis functions from an arbitrary pruning of a full dyadic tree structured filter bank as orthogonal pulse shapes for conventional QAM symbols. The multi-scale modulation (MSM) and M-band wavelet modulation (MWM) schemes which have been recently introduced are handled as special cases, with the added benefit of an entire library of potentially superior sets of basis functions. The figures of merit are derived and it is shown that the power spectral density is equivalent to that for QAM (in fact, QAM is another special case) and hence directly applicable in existing systems employing this standard modulation. Two key advantages of this method are increased flexibility in time-frequency partitioning and an efficient all-digital filter bank implementation, making the WPM scheme more robust to a larger set of interferences (both temporal and sinusoidal) and computationally attractive as well.

Full complex spatial filtering with a phase mostly DMD. [Deformable Mirror Device

NASA Technical Reports Server (NTRS)

Florence, James M.; Juday, Richard D.

1991-01-01

A new technique for implementing fully complex spatial filters with a phase mostly deformable mirror device (DMD) light modulator is described. The technique combines two or more phase-modulating flexure-beam mirror elements into a single macro-pixel. By manipulating the relative phases of the individual sub-pixels within the macro-pixel, the amplitude and the phase can be independently set for this filtering element. The combination of DMD sub-pixels into a macro-pixel is accomplished by adjusting the optical system resolution, thereby trading off system space bandwidth product for increased filtering flexibility. Volume in the larger dimensioned space, space bandwidth-complex axes count, is conserved. Experimental results are presented mapping out the coupled amplitude and phase characteristics of the individual flexure-beam DMD elements and demonstrating the independent control of amplitude and phase in a combined macro-pixel. This technique is generally applicable for implementation with any type of phase modulating light modulator.

Supplementing research ethics training in psychiatry residents: A five-tier approach.

PubMed

Viswanath, Biju; Jayarajan, Rajan Nishanth; Chandra, Prabha S; Chaturvedi, Santosh K

2018-04-01

Ethics training is a key step in the research supervision of psychiatry trainees and there is need for a structured educational module. We developed a new research ethics training module for psychiatry residents - The Five-Tier Approach. Twenty-five first year psychiatry residents of an academic psychiatric training centre in India participated in this multi-session workshop. Module 1 included the completion of NIH online certification course for research ethics training. Module 2 was a one-hour interactive group discussion on ethical principles in research. Module 3 was a two-hour session consisting of case-based group discussion of nine selected research vignettes. Module 4 involved preparation of an informed consent form. Module 5 was a mock ethics committee role-played by seven students while the larger group observed using a Fish Bowl technique and provided feedback. Assessments were done during the third and final modules. During the third module, understanding regarding certain areas - autonomy, benefits and justice was found to be inadequate. In the final step, all ethical aspects were covered by the students. This five-tier approach seems like a superior tool for research ethics training in academic institutions, especially in Southeast Asia, where the student-teacher ratios are generally very high. Copyright © 2018 Elsevier B.V. All rights reserved.

Chaotic Dynamics of a Josephson Junction with a Ratchet Potential and Current-Modulating Damping

NASA Astrophysics Data System (ADS)

Li, Fei; Li, Wenwu; Xu, Lan

2018-06-01

The chaotic dynamics of a Josephson junction with a ratchet potential and current-modulating damping are studied. Under the first-order approximation, we construct the general solution of the first-order equation whose boundedness condition contains the famous Melnikov chaotic criterion. Based on the general solution, the incomputability and unpredictability of the system's chaotic behavior are discussed. For the case beyond perturbation conditions, the evolution of stroboscopic Poincaré sections shows that the system undergoes a quasi-periodic transition to chaos with an increasing intensity of the rf-current. Through a suitable feedback controlling strategy, the chaos can be effectively suppressed and the intensity of the controller can vary in a large range. It is also found that the current between the two separated superconductors increases monotonously in some specific parameter spaces.

Chaotic Dynamics of a Josephson Junction with a Ratchet Potential and Current-Modulating Damping

NASA Astrophysics Data System (ADS)

Li, Fei; Li, Wenwu; Xu, Lan

2018-04-01

The chaotic dynamics of a Josephson junction with a ratchet potential and current-modulating damping are studied. Under the first-order approximation, we construct the general solution of the first-order equation whose boundedness condition contains the famous Melnikov chaotic criterion. Based on the general solution, the incomputability and unpredictability of the system's chaotic behavior are discussed. For the case beyond perturbation conditions, the evolution of stroboscopic Poincaré sections shows that the system undergoes a quasi-periodic transition to chaos with an increasing intensity of the rf-current. Through a suitable feedback controlling strategy, the chaos can be effectively suppressed and the intensity of the controller can vary in a large range. It is also found that the current between the two separated superconductors increases monotonously in some specific parameter spaces.

Al2O3 and TiO2 atomic layer deposition on copper for water corrosion resistance.

PubMed

Abdulagatov, A I; Yan, Y; Cooper, J R; Zhang, Y; Gibbs, Z M; Cavanagh, A S; Yang, R G; Lee, Y C; George, S M

2011-12-01

Al(2)O(3) and TiO(2) atomic layer deposition (ALD) were employed to develop an ultrathin barrier film on copper to prevent water corrosion. The strategy was to utilize Al(2)O(3) ALD as a pinhole-free barrier and to protect the Al(2)O(3) ALD using TiO(2) ALD. An initial set of experiments was performed at 177 °C to establish that Al(2)O(3) ALD could nucleate on copper and produce a high-quality Al(2)O(3) film. In situ quartz crystal microbalance (QCM) measurements verified that Al(2)O(3) ALD nucleated and grew efficiently on copper-plated quartz crystals at 177 °C using trimethylaluminum (TMA) and water as the reactants. An electroplating technique also established that the Al(2)O(3) ALD films had a low defect density. A second set of experiments was performed for ALD at 120 °C to study the ability of ALD films to prevent copper corrosion. These experiments revealed that an Al(2)O(3) ALD film alone was insufficient to prevent copper corrosion because of the dissolution of the Al(2)O(3) film in water. Subsequently, TiO(2) ALD was explored on copper at 120 °C using TiCl(4) and water as the reactants. The resulting TiO(2) films also did not prevent the water corrosion of copper. Fortunately, Al(2)O(3) films with a TiO(2) capping layer were much more resilient to dissolution in water and prevented the water corrosion of copper. Optical microscopy images revealed that TiO(2) capping layers as thin as 200 Å on Al(2)O(3) adhesion layers could prevent copper corrosion in water at 90 °C for ~80 days. In contrast, the copper corroded almost immediately in water at 90 °C for Al(2)O(3) and ZnO films by themselves on copper. Ellipsometer measurements revealed that Al(2)O(3) films with a thickness of ~200 Å and ZnO films with a thickness of ~250 Å dissolved in water at 90 °C in ~10 days. In contrast, the ellipsometer measurements confirmed that the TiO(2) capping layers with thicknesses of ~200 Å on the Al(2)O(3) adhesion layers protected the copper for ~80 days in water at 90 °C. The TiO(2) ALD coatings were also hydrophilic and facilitated H(2)O wetting to copper wire mesh substrates. © 2011 American Chemical Society

GABAA receptor positive allosteric modulators modify the abuse-related behavioral and neurochemical effects of methamphetamine in rhesus monkeys.

PubMed

Berro, Laís F; Andersen, Monica L; Tufik, Sergio; Howell, Leonard L

2017-09-01

GABA A receptor positive allosteric modulators (GABA A receptor modulators) are commonly used for the treatment of insomnia. Nevertheless, the effects of these compounds on psychostimulant-induced sleep impairment are poorly understood. Because GABA A receptor modulators have been shown to decrease the abuse-related effects of psychostimulants, the aim of the present study was to evaluate the effects of temazepam (0.3, 1.0 or 3.0 mg/kg) and eszopiclone (0.3, 1.0 or 3.0 mg/kg), two GABA A receptor modulators, on the behavioral neuropharmacology of methamphetamine in adult rhesus macaques (n = 5). Sleep-like measures and general daytime activity were evaluated with Actiwatch monitors. Methamphetamine self-administration (0.03 mg/kg/inf) was evaluated during morning sessions. Methamphetamine-induced dopamine overflow was assessed through in vivo microdialysis targeting the nucleus accumbens. Nighttime treatment with either temazepam or eszopiclone was ineffective in improving sleep-like measures disrupted by methamphetamine self-administration. Acute pretreatment with a low dose of temazepam before self-administration sessions increased methamphetamine self-administration without affecting normal daytime home-cage activity. At a high dose, acute temazepam pretreatment decreased methamphetamine self-administration and attenuated methamphetamine-induced increases in dopamine in the nucleus accumbens, without decreasing general daytime activity. Acute eszopiclone treatment exerted no effects on methamphetamine intake or drug-induced increases in dopamine. Our study suggests that treatments based on GABA A receptor modulators are not effective for the treatment of sleep disruption in the context of psychostimulant use. In addition, distinct GABA A receptor modulators differentially modulated the abuse-related effects of methamphetamine, with acute treatment with the high efficacy GABA A receptor modulator temazepam decreasing the behavioral and neurochemical effects of methamphetamine. Copyright © 2017 Elsevier Ltd. All rights reserved.

Evaluation of an Interactive Undergraduate Cosmology Curriculum

NASA Astrophysics Data System (ADS)

White, Aaron; Coble, Kimberly A.; Martin, Dominique; Hayes, Patrycia; Targett, Tom; Cominsky, Lynn R.

2018-06-01

The Big Ideas in Cosmology is an immersive set of web-based learning modules that integrates text, figures, and visualizations with short and long interactive tasks as well as labs that allow students to manipulate and analyze real cosmological data. This enables the transformation of general education astronomy and cosmology classes from primarily lecture and book-based courses to a format that builds important STEM skills, while engaging those outside the field with modern discoveries and a more realistic sense of practices and tools used by professional astronomers. Over two semesters, we field-tested the curriculum in general education cosmology classes at a state university in California [N ~ 80]. We administered pre- and post-instruction multiple-choice and open-ended content surveys as well as the CLASS, to gauge the effectiveness of the course and modules. Questions addressed included the structure, composition, and evolution of the universe, including students’ reasoning and “how we know.”Module development and evaluation was supported by NASA ROSES E/PO Grant #NNXl0AC89G, the Illinois Space Grant Consortium, the Fermi E/PO program, Sonoma State University’s Space Science Education and Public Outreach Group, and San Francisco State University. The modules are published by Great River Learning/Kendall-Hunt.

Validation of the King's Sarcoidosis Questionnaire (KSQ) in a Dutch sarcoidosis population.

PubMed

Van Manen, Mirjam J G; Wapenaar, Monique; Strookappe, Bert; Drent, Marjolein; Elfferich, Marjon; de Vries, Jolanda; Gosker, Harry R; Birring, Surinder S; Patel, Amit S; van den Toorn, Leon; van den Blink, Bernt; Boomars, Karin; Hoitsma, Elske; Wijsenbeek, Marlies S

2016-03-29

The King's Sarcoidosis Questionnaire (KSQ) is a brief questionnaire assessing health status using five modules (General Health Status, Lung, Eyes, Skin, Medication) in patients with sarcoidosis. The KSQ was only validated in one English sarcoidosis cohort. The aim of this study was to validate the KSQ in a Dutch sarcoidosis population. The KSQ was translated according to international guidelines and tested in interviews with patients. Consecutive outpatients completed multiple questionnaires twice, two weeks apart. Construct validity, internal consistency and repeatability were determined. Of the 98 patients included 85 had lung, 22 skin and 24 eye disease. There was good construct validity of the KSQ General Health Status module against the World Health Organization Quality of Life-BREF questionnaire. The Medication module correlated weak to moderate with most questionnaires. The correlations with organ-specific questionnaires varied from strong for Eyes (r=0.75), Skin (r=-0.62) to moderate for Lung (r=-0.45 with MRC breathlessness scale). Internal consistency was good for all KSQ modules (Cronbach's α 0.72-0.93). Intraclass correlation coefficients (0.70-0.90) and Bland-Altman plots showed good repeatability of the KSQ. The Dutch KSQ is the first translation of the English KSQ, validated in a Dutch sarcoidosis population.

NASA's Global Climate Change Education (GCCE) Program: New modules

NASA Astrophysics Data System (ADS)

Witiw, M. R.; Myers, R. J.; Schwerin, T. G.

2010-12-01

In existence for over 10 years, the Earth System Science Educational Alliance (ESSEA) through the Institute of Global Environmental Strategies (IGES) has developed a series of modules on Earth system science topics. To date, over 80 educational modules have been developed. The primary purpose of these modules is to provide graduate courses for teacher education. A typical course designed for teachers typically consists of from three to five content modules and a primer on problem-based learning. Each module is designed to take three weeks in a normal university semester. Course delivery methods vary. Some courses are completed totally online. Others are presented in the classroom. Still others are delivered using a hybrid method which combines classroom meetings with online delivery of content. Although originally designed for teachers and education students, recent changes, provide a format for general education students to use these module. In 2009, under NASA’s Global Climate Change Education (GCCE) initiative, IGES was tasked to develop 16 new modules addressing the topic of climate change. Two of the modules recently developed under this program address the topics of sunspots and thermal islands. Sunspots is a problem-based learning module where students are provided resources and sample investigations related to sunspots. The history of sunspot observations, the structure of sunspots and the possible role sunspots may have in Earth’s climate are explored. Students are then asked to determine what effects a continued minimum in sunspot activity may have on the climate system. In Thermal Islands, the topic of urban heat islands is addressed. How heat islands are produced and the role of urban heat islands in exacerbating heat waves are two of the topics covered in the resources. In this problem-based learning module, students are asked to think of mitigating strategies for these thermal islands as Earth’s urban population grows over the next 50 years. These modules were successfully piloted with undergraduate students at Seattle Pacific University.

Combinatorics of Generalized Bethe Equations

NASA Astrophysics Data System (ADS)

Kozlowski, Karol K.; Sklyanin, Evgeny K.

2013-10-01

A generalization of the Bethe ansatz equations is studied, where a scalar two-particle S-matrix has several zeroes and poles in the complex plane, as opposed to the ordinary single pole/zero case. For the repulsive case (no complex roots), the main result is the enumeration of all distinct solutions to the Bethe equations in terms of the Fuss-Catalan numbers. Two new combinatorial interpretations of the Fuss-Catalan and related numbers are obtained. On the one hand, they count regular orbits of the permutation group in certain factor modules over {{Z}^M}, and on the other hand, they count integer points in certain M-dimensional polytopes.

Interpersonal relationship modulates brain responses to outcome evaluation when gambling for/against others: an electrophysiological analysis.

PubMed

Leng, Yue; Zhou, Xiaolin

2014-10-01

When individuals play a gambling task and their actions have consequences for observers, how are the brain responses of the performers modulated by their interpersonal relationship with the observers? To address this issue, we examined the event-related potentials responses in performers while they played two gambling games: one during which they tried to earn money for the observers instead of themselves (i.e., Experiment 1) and another gambling game during which they attempted to earn money from the observers (i.e., Experiment 2). In Experiment 1, ERP results showed that when gambling for either the friends or the strangers, the feedback-related negativity (FRN) responses were more negative-going to the losses than to the gains. The FRN effect (loss minus gain) was significantly larger when gambling for the friends than for the strangers. The general P300 response was more positive-going when gambling for the friends than for the strangers. These results suggested that gambling for others enables individuals to assess the outcome from the interests of the other people, consequently, the FRN response may be driven by the evaluative process related to interests of the others. Because one׳s own economic interests were not involved, the performers׳ brain responses during both the early, semi-automatic stage (i.e., the FRN) and the later, controlled stage (i.e., the P300) of outcome evaluation were modulated by the interpersonal relationship between the performers and the observers. In Experiment 2, ERP results revealed that when gambling against others, the FRN response was more negative-going to the losses than to the gains, as well. However, neither the FRN effect nor the general FRN response was modulated by interpersonal relationship. The general P300 response was more positive-going when gambling against the stranger than against the friend. These results suggested that when gambling against others, the performers׳ FRN response may be driven by two evaluative processes: one is related to the interests of their own, and another is related to the interests of the other people; and the former one plays a dominant role. Because of highly self-involvement, only the performers׳ brain responses during the later controlled stage of outcome evaluation were modulated by interpersonal relationship. The present study extended previous research on brain responses to outcome evaluation when decision making actions have consequences for the other people by suggesting that the FRN response in the performer could also be driven by two evaluative processes. In addition, whether the FRN in the performer was modulated by interpersonal relationship depends on which evaluative process plays a dominant role. However, the P300 in the performer could always be modulated by interpersonal relationship. These findings provide evidence on outcome evaluation being composed of an early semi-automatic primitive process and a later controlled cognitive/affective appraisal process. Copyright © 2014 Elsevier Ltd. All rights reserved.

Label-free super-resolution with coherent nonlinear structured-illumination microscopy

NASA Astrophysics Data System (ADS)

Huttunen, Mikko J.; Abbas, Aazad; Upham, Jeremy; Boyd, Robert W.

2017-08-01

Structured-illumination microscopy enables up to a two-fold lateral resolution improvement by spatially modulating the intensity profile of the illumination beam. We propose a novel way to generalize the concept of structured illumination to nonlinear widefield modalities by spatially modulating, instead of field intensities, the phase of the incident field while interferometrically measuring the complex-valued scattered field. We numerically demonstrate that for second-order and third-order processes an almost four- and six-fold increase in lateral resolution is achievable, respectively. This procedure overcomes the conventional Abbe diffraction limit and provides new possibilities for label-free super-resolution microscopy.

Study of structure and antireflective properties of LaF3/HfO2/SiO2 and LaF3/HfO2/MgF2 trilayers for UV applications

NASA Astrophysics Data System (ADS)

Marszalek, K.; Jaglarz, J.; Sahraoui, B.; Winkowski, P.; Kanak, J.

2015-01-01

The aim of this paper is to study antireflective properties of the tree-layer systems LaF3/HfO2/SiO2 and LaF3/HfO2/MgF2 deposited on heated optical glass substrates. The films were evaporated by the use two deposition techniques. In first method oxide films were prepared by means of e-gun evaporation in vacuum of 5 × 10-5 mbar in the presence of oxygen. The second was used for the deposition of fluoride films. They were obtained by means of thermal source evaporation. Simulation of reflectance was performed for 1M2H1L (Quarter Wavelength Optical Thickness) film stack on an optical quartz glass with the refractive index n = 1.46. The layer thickness was optimized to achieve the lowest light scattering from glass surface covered with dioxide and fluoride films. The values of the interface roughness were determined through atomic force microscopy measurements. The essence of performed calculation was to find minimum reflectance of light in wide ultraviolet region. The spectral dispersion of the refractive index needed for calculations was determined from ellipsometric measurements using the spectroscopic ellipsometer M2000. Additionally, the total reflectance measurements in integrating sphere coupled with Perkin Elmer 900 spectrophotometer were performed. These investigations allowed to determine the influence of such film features like surface and interface roughness on light scattering.

Interactive web-based learning modules prior to general medicine advanced pharmacy practice experiences.

PubMed

Isaacs, Alex N; Walton, Alison M; Nisly, Sarah A

2015-04-25

To implement and evaluate interactive web-based learning modules prior to advanced pharmacy practice experiences (APPEs) on inpatient general medicine. Three clinical web-based learning modules were developed for use prior to APPEs in 4 health care systems. The aim of the interactive modules was to strengthen baseline clinical knowledge before the APPE to enable the application of learned material through the delivery of patient care. For the primary endpoint, postassessment scores increased overall and for each individual module compared to preassessment scores. Postassessment scores were similar among the health care systems. The survey demonstrated positive student perceptions of this learning experience. Prior to inpatient general medicine APPEs, web-based learning enabled the standardization and assessment of baseline student knowledge across 4 health care systems.

Homogenized modeling methodology for 18650 lithium-ion battery module under large deformation

PubMed Central

Tang, Liang; Cheng, Pengle

2017-01-01

Effective lithium-ion battery module modeling has become a bottleneck for full-size electric vehicle crash safety numerical simulation. Modeling every single cell in detail would be costly. However, computational accuracy could be lost if the module is modeled by using a simple bulk material or rigid body. To solve this critical engineering problem, a general method to establish a computational homogenized model for the cylindrical battery module is proposed. A single battery cell model is developed and validated through radial compression and bending experiments. To analyze the homogenized mechanical properties of the module, a representative unit cell (RUC) is extracted with the periodic boundary condition applied on it. An elastic–plastic constitutive model is established to describe the computational homogenized model for the module. Two typical packing modes, i.e., cubic dense packing and hexagonal packing for the homogenized equivalent battery module (EBM) model, are targeted for validation compression tests, as well as the models with detailed single cell description. Further, the homogenized EBM model is confirmed to agree reasonably well with the detailed battery module (DBM) model for different packing modes with a length scale of up to 15 × 15 cells and 12% deformation where the short circuit takes place. The suggested homogenized model for battery module makes way for battery module and pack safety evaluation for full-size electric vehicle crashworthiness analysis. PMID:28746390

Homogenized modeling methodology for 18650 lithium-ion battery module under large deformation.

PubMed

Tang, Liang; Zhang, Jinjie; Cheng, Pengle

2017-01-01

Effective lithium-ion battery module modeling has become a bottleneck for full-size electric vehicle crash safety numerical simulation. Modeling every single cell in detail would be costly. However, computational accuracy could be lost if the module is modeled by using a simple bulk material or rigid body. To solve this critical engineering problem, a general method to establish a computational homogenized model for the cylindrical battery module is proposed. A single battery cell model is developed and validated through radial compression and bending experiments. To analyze the homogenized mechanical properties of the module, a representative unit cell (RUC) is extracted with the periodic boundary condition applied on it. An elastic-plastic constitutive model is established to describe the computational homogenized model for the module. Two typical packing modes, i.e., cubic dense packing and hexagonal packing for the homogenized equivalent battery module (EBM) model, are targeted for validation compression tests, as well as the models with detailed single cell description. Further, the homogenized EBM model is confirmed to agree reasonably well with the detailed battery module (DBM) model for different packing modes with a length scale of up to 15 × 15 cells and 12% deformation where the short circuit takes place. The suggested homogenized model for battery module makes way for battery module and pack safety evaluation for full-size electric vehicle crashworthiness analysis.

Knowledge transfer for the management of dementia: a cluster-randomised trial of blended learning in general practice

PubMed Central

2010-01-01

Background The implementation of new medical knowledge into general practice is a complex process. Blended learning may offer an effective and efficient educational intervention to reduce the knowledge-to-practice gap. The aim of this study was to compare knowledge acquisition about dementia management between a blended learning approach using online modules in addition to quality circles (QCs) and QCs alone. Methods In this cluster-randomised trial with QCs as clusters and general practitioners (GPs) as participants, 389 GPs from 26 QCs in the western part of Germany were invited to participate. Data on the GPs' knowledge were obtained at three points in time by means of a questionnaire survey. Primary outcome was the knowledge gain before and after the interventions. A subgroup analysis of the users of the online modules was performed. Results 166 GPs were available for analysis and filled out a knowledge test at least two times. A significant increase of knowledge was found in both groups that indicated positive learning effects of both approaches. However, there was no significant difference between the groups. A subgroup analysis of the GPs who self-reported that they had actually used the online modules showed that they had a significant increase in their knowledge scores. Conclusion A blended learning approach was not superior to a QCs approach for improving knowledge about dementia management. However, a subgroup of GPs who were motivated to actually use the online modules had a gain in knowledge. Trial registration Current Controlled Trials ISRCTN36550981. PMID:20047652

A Self-Instructional Course in Student Financial Aid Administration. Module 6: General Student Eligibility. Second Edition.

ERIC Educational Resources Information Center

Washington Consulting Group, Inc., Washington, DC.

Module 6 of a 17-module self-instructional course on student financial aid administration (for novice aid administrators and other personnel) presents a systematic introduction to the management of federal financial aid programs authorized by Title IV of the Higher Education Act with an emphasis on general student eligibility. Identifying the…

Length-Two Representations of Quantum Affine Superalgebras and Baxter Operators

NASA Astrophysics Data System (ADS)

Zhang, Huafeng

2018-03-01

Associated to quantum affine general linear Lie superalgebras are two families of short exact sequences of representations whose first and third terms are irreducible: the Baxter TQ relations involving infinite-dimensional representations; the extended T-systems of Kirillov-Reshetikhin modules. We make use of these representations over the full quantum affine superalgebra to define Baxter operators as transfer matrices for the quantum integrable model and to deduce Bethe Ansatz Equations, under genericity conditions.

Swimming of a sphere in a viscous incompressible fluid with inertia

NASA Astrophysics Data System (ADS)

Felderhof, B. U.; Jones, R. B.

2017-08-01

The swimming of a sphere immersed in a viscous incompressible fluid with inertia is studied for surface modulations of small amplitude on the basis of the Navier-Stokes equations. The mean swimming velocity and the mean rate of dissipation are expressed as quadratic forms in term of the surface displacements. With a choice of a basis set of modes the quadratic forms correspond to two Hermitian matrices. Optimization of the mean swimming velocity for given rate of dissipation requires the solution of a generalized eigenvalue problem involving the two matrices. It is found for surface modulations of low multipole order that the optimal swimming efficiency depends in intricate fashion on a dimensionless scale number involving the radius of the sphere, the period of the cycle, and the kinematic viscosity of the fluid.

[Teaching family medicine in Lausanne].

PubMed

Bischoff, Thomas; Junod, Michel; Cornuz, Jacques; Herzig, Lilli; Bonvin, Raphael

2010-12-01

The Faculty of Biology and Medicine of Lausanne has integrated education of family medicine all along its new undergraduate medical curriculum. The Institute of general medicine is in charge to implement those offers among which two are presented hereafter. In the new module "Generalism" several courses cover the specificities of the discipline as for example medical decision in the practice. A mandatory one-month internship in the medical practice offers an experiential immersion into family medicine for all students. In a meeting at the end of their internship, students discuss in group with their peers their individual experiences and are asked to identify, based on their personal experience, the general concepts of the specialty of family medicine and general practice.

Earth Observatory Satellite system definition study. Report 5: System design and specifications. Volume 3: General purpose spacecraft segment and module specifications

NASA Technical Reports Server (NTRS)

1974-01-01

The specifications for the Earth Observatory Satellite (EOS) general purpose aircraft segment are presented. The satellite is designed to provide attitude stabilization, electrical power, and a communications data handling subsystem which can support various mission peculiar subsystems. The various specifications considered include the following: (1) structures subsystem, (2) thermal control subsystem, (3) communications and data handling subsystem module, (4) attitude control subsystem module, (5) power subsystem module, and (6) electrical integration subsystem.

Generalized channeled polarimetry.

PubMed

Alenin, Andrey S; Tyo, J Scott

2014-05-01

Channeled polarimeters measure polarization by modulating the measured intensity in order to create polarization-dependent channels that can be demodulated to reveal the desired polarization information. A number of channeled systems have been described in the past, but their proposed designs often unintentionally sacrifice optimality for ease of algebraic reconstruction. To obtain more optimal systems, a generalized treatment of channeled polarimeters is required. This paper describes methods that enable handling of multi-domain modulations and reconstruction of polarization information using linear algebra. We make practical choices regarding use of either Fourier or direct channels to make these methods more immediately useful. Employing the introduced concepts to optimize existing systems often results in superficial system changes, like changing the order, orientation, thickness, or spacing of polarization elements. For the two examples we consider, we were able to reduce noise in the reconstruction to 34.1% and 57.9% of the original design values.

Compression of Flow Can Reveal Overlapping-Module Organization in Networks

NASA Astrophysics Data System (ADS)

Viamontes Esquivel, Alcides; Rosvall, Martin

2011-10-01

To better understand the organization of overlapping modules in large networks with respect to flow, we introduce the map equation for overlapping modules. In this information-theoretic framework, we use the correspondence between compression and regularity detection. The generalized map equation measures how well we can compress a description of flow in the network when we partition it into modules with possible overlaps. When we minimize the generalized map equation over overlapping network partitions, we detect modules that capture flow and determine which nodes at the boundaries between modules should be classified in multiple modules and to what degree. With a novel greedy-search algorithm, we find that some networks, for example, the neural network of the nematode Caenorhabditis elegans, are best described by modules dominated by hard boundaries, but that others, for example, the sparse European-roads network, have an organization of highly overlapping modules.

School-to-Work and Inclusion in General Education Teacher Preparation Programs: Instructional Modules for Middle Childhood Subject Area Methods Courses.

ERIC Educational Resources Information Center

Hamill, Lee B.; Geer, Cindy H.

Six instructional modules for middle childhood subject area methods courses are designed to target students in preservice middle childhood general education programs. The modules have been developed for each of the content area methods courses to ensure all preservice teachers have ample exposure to the school-to-work (STW) philosophy and…

Moisture-temperature degradation in module encapsulants: The general problem of moisture in photovoltaic encapsulants

NASA Technical Reports Server (NTRS)

Mon, G. R.

1985-01-01

A general research approach was outlined toward understanding water-module interactions and the influence of temperature involving the need to: quantify module performance loss versus level of accumulated degradation, establish the dependence of the degradation reaction rate on module moisture and temperature levels, and determine module moisture and temperature levels in field environments. These elements were illustrated with examples drawn from studies of the now relatively well understood module electrochemical degradation process. Research data presented include temperature and humidity-dependent equilibrium leakage current values for multiparameter module material and design configurations. The contributions of surface, volume, and interfacial conductivities was demonstrated. Research directions were suggested to more fully understand the contributions to overall module conductivity of surface, volume, and interfacial conductivities over ranges of temperature and relative humidity characteristic of field environments.

Optics of two-stage photovoltaic concentrators with dielectric second stages.

PubMed

Ning, X; O'Gallagher, J; Winston, R

1987-04-01

Two-stage photovoltaic concentrators with Fresnel lenses as primaries and dielectric totally internally reflecting nonimaging concentrators as secondaries are discussed. The general design principles of such two-stage systems are given. Their optical properties are studied and analyzed in detail using computer ray trace procedures. It is found that the two-stage concentrator offers not only a higher concentration or increased acceptance angle, but also a more uniform flux distribution on the photovoltaic cell than the point focusing Fresnel lens alone. Experimental measurements with a two-stage prototype module are presented and compared to the analytical predictions.

Optics of two-stage photovoltaic concentrators with dielectric second stages

NASA Astrophysics Data System (ADS)

Ning, Xiaohui; O'Gallagher, Joseph; Winston, Roland

1987-04-01

Two-stage photovoltaic concentrators with Fresnel lenses as primaries and dielectric totally internally reflecting nonimaging concentrators as secondaries are discussed. The general design principles of such two-stage systems are given. Their optical properties are studied and analyzed in detail using computer ray trace procedures. It is found that the two-stage concentrator offers not only a higher concentration or increased acceptance angle, but also a more uniform flux distribution on the photovoltaic cell than the point focusing Fresnel lens alone. Experimental measurements with a two-stage prototype module are presented and compared to the analytical predictions.

Generalized hamming networks and applications.

PubMed

Koutroumbas, Konstantinos; Kalouptsidis, Nicholas

2005-09-01

In this paper the classical Hamming network is generalized in various ways. First, for the Hamming maxnet, a generalized model is proposed, which covers under its umbrella most of the existing versions of the Hamming Maxnet. The network dynamics are time varying while the commonly used ramp function may be replaced by a much more general non-linear function. Also, the weight parameters of the network are time varying. A detailed convergence analysis is provided. A bound on the number of iterations required for convergence is derived and its distribution functions are given for the cases where the initial values of the nodes of the Hamming maxnet stem from the uniform and the peak distributions. Stabilization mechanisms aiming to prevent the node(s) with the maximum initial value diverging to infinity or decaying to zero are described. Simulations demonstrate the advantages of the proposed extension. Also, a rough comparison between the proposed generalized scheme as well as the original Hamming maxnet and its variants is carried out in terms of the time required for convergence, in hardware implementations. Finally, the other two parts of the Hamming network, namely the competitors generating module and the decoding module, are briefly considered in the framework of various applications such as classification/clustering, vector quantization and function optimization.

Floating-Point Modules Targeted for Use with RC Compilation Tools

NASA Technical Reports Server (NTRS)

Sahin, Ibrahin; Gloster, Clay S.

2000-01-01

Reconfigurable Computing (RC) has emerged as a viable computing solution for computationally intensive applications. Several applications have been mapped to RC system and in most cases, they provided the smallest published execution time. Although RC systems offer significant performance advantages over general-purpose processors, they require more application development time than general-purpose processors. This increased development time of RC systems provides the motivation to develop an optimized module library with an assembly language instruction format interface for use with future RC system that will reduce development time significantly. In this paper, we present area/performance metrics for several different types of floating point (FP) modules that can be utilized to develop complex FP applications. These modules are highly pipelined and optimized for both speed and area. Using these modules, and example application, FP matrix multiplication, is also presented. Our results and experiences show, that with these modules, 8-10X speedup over general-purpose processors can be achieved.

DNA Replication and Transcription: An Innovative Teaching Strategy

ERIC Educational Resources Information Center

Fossey, Annabel; Hancock, Carolyn

2005-01-01

First-year students in genetics at the University of KwaZulu-Natal, South Africa, attend two general biology modules, one in each semester. Teaching involves four formal lectures per week of 45 min each, one 3-h practical, and one lecture period tutorial. These students, graduating from secondary education, are well schooled in rote learning but…

Measures of Autonomic Nervous System

DTIC Science & Technology

2011-04-01

activation encompass non-invasive tools, which measure cardiac, skin conductance, respiratory , and vascular activity. Choice of tools is dependent upon...digestion, excretion, and cardiac and respiratory activity. The ANS consists of the sympathetic and parasympathetic divisions and acts through a... respiratory cycles. Generally, these two systems should be seen as permanently modulating vital functions to achieve homeostasis. Since both systems are

Continuous-variable quantum key distribution with a leakage from state preparation

NASA Astrophysics Data System (ADS)

Derkach, Ivan; Usenko, Vladyslav C.; Filip, Radim

2017-12-01

We address side-channel leakage in a trusted preparation station of continuous-variable quantum key distribution with coherent and squeezed states. We consider two different scenarios: multimode Gaussian modulation, directly accessible to an eavesdropper, or side-channel loss of the signal states prior to the modulation stage. We show the negative impact of excessive modulation on both the coherent- and squeezed-state protocols. The impact is more pronounced for squeezed-state protocols and may require optimization of squeezing in the case of noisy quantum channels. Further, we demonstrate that the coherent-state protocol is immune to side-channel signal state leakage prior to modulation, while the squeezed-state protocol is vulnerable to such attacks, becoming more sensitive to the noise in the channel. In the general case of noisy quantum channels the signal squeezing can be optimized to provide best performance of the protocol in the presence of side-channel leakage prior to modulation. Our results demonstrate that leakage from the trusted source in continuous-variable quantum key distribution should not be underestimated and squeezing optimization is needed to overcome coherent state protocols.

Directional spectra of ocean waves from microwave backscatter: A physical optics solution with application to the short-pulse and two-frequency measurement techniques

NASA Technical Reports Server (NTRS)

Jackson, F. C.

1979-01-01

Two simple microwave radar techniques that are potentially capable of providing routine satellite measurements of the directional spectrum of ocean waves were developed. One technique, the short pulse technique, makes use of very short pulses to resolve ocean surface wave contrast features in the range direction; the other technique, the two frequency correlation technique makes use of coherency in the transmitted waveform to detect the large ocean wave contrast modulation as a beat or mixing frequency in the power backscattered at two closely separated microwave frequencies. A frequency domain analysis of the short pulse and two frequency systems shows that the two measurement systems are essentially duals; they each operate on the generalized (three frequency) fourth-order statistical moment of the surface transfer function in different, but symmetrical ways, and they both measure the same directional contrast modulation spectrum. A three dimensional physical optics solution for the fourth-order moment was obtained for backscatter in the near vertical, specular regime, assuming Gaussian surface statistics.

Neural basis of individualistic and collectivistic views of self.

PubMed

Chiao, Joan Y; Harada, Tokiko; Komeda, Hidetsugu; Li, Zhang; Mano, Yoko; Saito, Daisuke; Parrish, Todd B; Sadato, Norihiro; Iidaka, Tetsuya

2009-09-01

Individualism and collectivism refer to cultural values that influence how people construe themselves and their relation to the world. Individualists perceive themselves as stable entities, autonomous from other people and their environment, while collectivists view themselves as dynamic entities, continually defined by their social context and relationships. Despite rich understanding of how individualism and collectivism influence social cognition at a behavioral level, little is known about how these cultural values modulate neural representations underlying social cognition. Using cross-cultural functional magnetic resonance imaging (fMRI), we examined whether the cultural values of individualism and collectivism modulate neural activity within medial prefrontal cortex (MPFC) during processing of general and contextual self judgments. Here, we show that neural activity within the anterior rostral portion of the MPFC during processing of general and contextual self judgments positively predicts how individualistic or collectivistic a person is across cultures. These results reveal two kinds of neural representations of self (eg, a general self and a contextual self) within MPFC and demonstrate how cultural values of individualism and collectivism shape these neural representations. 2008 Wiley-Liss, Inc.

Effects of Implementing a Hybrid Wet Lab and Online Module Lab Curriculum into a General Chemistry Course: Impacts on Student Performance and Engagement with the Chemistry Triplet

ERIC Educational Resources Information Center

Irby, Stefan M.; Borda, Emily J.; Haupt, Justin

2018-01-01

Here, we describe the implementation a hybrid general chemistry teaching laboratory curriculum that replaces a portion of a course's traditional "wet lab" experiences with online virtual lab modules. These modules intentionally utilize representations on all three levels of the chemistry triplet-macroscopic, submicroscopic, and symbolic.…

Land Application of Wastes: An Educational Program. Design Procedures for Land Application of Wastes - Module 6, Objectives, Script and Figures.

ERIC Educational Resources Information Center

Clarkson, W. W.; And Others

The purpose of this module is to develop a general procedure to decide the feasibility of land application as a waste management alternative, given a specific problem situation. This information provides a framework within which to apply the information presented in all other modules in the program. An outline of the general procedure followed in…

47 CFR 2.1047 - Measurements required: Modulation characteristics.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 1 2010-10-01 2010-10-01 false Measurements required: Modulation characteristics. 2.1047 Section 2.1047 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL FREQUENCY... Certification § 2.1047 Measurements required: Modulation characteristics. (a) Voice modulated communication...

47 CFR 2.1047 - Measurements required: Modulation characteristics.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 47 Telecommunication 1 2011-10-01 2011-10-01 false Measurements required: Modulation characteristics. 2.1047 Section 2.1047 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL FREQUENCY... Certification § 2.1047 Measurements required: Modulation characteristics. (a) Voice modulated communication...

CT dose minimization using personalized protocol optimization and aggressive bowtie

NASA Astrophysics Data System (ADS)

Wang, Hui; Yin, Zhye; Jin, Yannan; Wu, Mingye; Yao, Yangyang; Tao, Kun; Kalra, Mannudeep K.; De Man, Bruno

2016-03-01

In this study, we propose to use patient-specific x-ray fluence control to reduce the radiation dose to sensitive organs while still achieving the desired image quality (IQ) in the region of interest (ROI). The mA modulation profile is optimized view by view, based on the sensitive organs and the ROI, which are obtained from an ultra-low-dose volumetric CT scout scan [1]. We use a clinical chest CT scan to demonstrate the feasibility of the proposed concept: the breast region is selected as the sensitive organ region while the cardiac region is selected as IQ ROI. Two groups of simulations are performed based on the clinical CT dataset: (1) a constant mA scan adjusted based on the patient attenuation (120 kVp, 300 mA), which serves as baseline; (2) an optimized scan with aggressive bowtie and ROI centering combined with patient-specific mA modulation. The results shows that the combination of the aggressive bowtie and the optimized mA modulation can result in 40% dose reduction in the breast region, while the IQ in the cardiac region is maintained. More generally, this paper demonstrates the general concept of using a 3D scout scan for optimal scan planning.

Task-dependent modulation of the visual sensory thalamus assists visual-speech recognition.

PubMed

Díaz, Begoña; Blank, Helen; von Kriegstein, Katharina

2018-05-14

The cerebral cortex modulates early sensory processing via feed-back connections to sensory pathway nuclei. The functions of this top-down modulation for human behavior are poorly understood. Here, we show that top-down modulation of the visual sensory thalamus (the lateral geniculate body, LGN) is involved in visual-speech recognition. In two independent functional magnetic resonance imaging (fMRI) studies, LGN response increased when participants processed fast-varying features of articulatory movements required for visual-speech recognition, as compared to temporally more stable features required for face identification with the same stimulus material. The LGN response during the visual-speech task correlated positively with the visual-speech recognition scores across participants. In addition, the task-dependent modulation was present for speech movements and did not occur for control conditions involving non-speech biological movements. In face-to-face communication, visual speech recognition is used to enhance or even enable understanding what is said. Speech recognition is commonly explained in frameworks focusing on cerebral cortex areas. Our findings suggest that task-dependent modulation at subcortical sensory stages has an important role for communication: Together with similar findings in the auditory modality the findings imply that task-dependent modulation of the sensory thalami is a general mechanism to optimize speech recognition. Copyright © 2018. Published by Elsevier Inc.

Electrical Spin Driving by g -Matrix Modulation in Spin-Orbit Qubits

NASA Astrophysics Data System (ADS)

Crippa, Alessandro; Maurand, Romain; Bourdet, Léo; Kotekar-Patil, Dharmraj; Amisse, Anthony; Jehl, Xavier; Sanquer, Marc; Laviéville, Romain; Bohuslavskyi, Heorhii; Hutin, Louis; Barraud, Sylvain; Vinet, Maud; Niquet, Yann-Michel; De Franceschi, Silvano

2018-03-01

In a semiconductor spin qubit with sizable spin-orbit coupling, coherent spin rotations can be driven by a resonant gate-voltage modulation. Recently, we have exploited this opportunity in the experimental demonstration of a hole spin qubit in a silicon device. Here we investigate the underlying physical mechanisms by measuring the full angular dependence of the Rabi frequency, as well as the gate-voltage dependence and anisotropy of the hole g factor. We show that a g -matrix formalism can simultaneously capture and discriminate the contributions of two mechanisms so far independently discussed in the literature: one associated with the modulation of the g factor, and measurable by Zeeman energy spectroscopy, the other not. Our approach has a general validity and can be applied to the analysis of other types of spin-orbit qubits.

Space Station

NASA Image and Video Library

1971-01-01

This is an artist's concept of the Research and Applications Modules (RAM). Evolutionary growth was an important consideration in space station plarning, and another project was undertaken in 1971 to facilitate such growth. The RAM study, conducted through a Marshall Space Flight Center contract with General Dynamics Convair Aerospace, resulted in the conceptualization of a series of RAM payload carrier-sortie laboratories, pallets, free-flyers, and payload and support modules. The study considered two basic manned systems. The first would use RAM hardware for sortie mission, where laboratories were carried into space and remained attached to the Shuttle for operational periods up to 7 days. The second envisioned a modular space station capability that could be evolved by mating RAM modules to the space station core configuration. The RAM hardware was to be built by Europeans, thus fostering international participation in the space program.

Mathematical models utilized in the retrieval of displacement information encoded in fringe patterns

NASA Astrophysics Data System (ADS)

Sciammarella, Cesar A.; Lamberti, Luciano

2016-02-01

All the techniques that measure displacements, whether in the range of visible optics or any other form of field methods, require the presence of a carrier signal. A carrier signal is a wave form modulated (modified) by an input, deformation of the medium. A carrier is tagged to the medium under analysis and deforms with the medium. The wave form must be known both in the unmodulated and the modulated conditions. There are two basic mathematical models that can be utilized to decode the information contained in the carrier, phase modulation or frequency modulation, both are closely connected. Basic problems connected to the detection and recovery of displacement information that are common to all optical techniques will be analyzed in this paper, focusing on the general theory common to all the methods independently of the type of signal utilized. The aspects discussed are those that have practical impact in the process of data gathering and data processing.

Investigation of thermal degradation with extrusion-based dispensing modules for 3D bioprinting technology.

PubMed

Lee, Hyungseok; Yoo, James J; Kang, Hyun-Wook; Cho, Dong-Woo

2016-02-04

Recently, numerous three-dimensional (3D) bioprinting systems have been introduced for the artificial regeneration of tissues. Among them, the extrusion-based dispensing module is the most widely used because of the processability it gives various biomaterials. The module uses high forces and temperature to dispense materials through a micro-nozzle. Generally, the harsh conditions induce thermal degradation of the material in the dispensing procedure. The thermal degradation affects the properties of the materials, and the change of the properties should be carefully controlled, because it severely affects the regeneration of tissues. Therefore, in this research, the relationship between the dispensing module and the thermal degradation of material was investigated. Extrusion-based dispensing modules can be divided into the syringe type (ST) and filament type (FT) based on working principles. We prepared a poly lactic-co-glycolic acid (PLGA) scaffold with the two methods at various time points. Then, the characteristics of the printed scaffolds were assessed by measuring molecular weight (M w), glass transition temperature (T g), in vitro degradation, compressive modulus, and cytocompatibility. The results showed that the PLGA scaffold with the FT dispensing module maintained its properties regardless of printing time points. In contrast, severe thermal degradation was observed in the scaffold group prepared by the ST dispensing module. Consequentially, it was obvious that the FT dispensing module was more suitable for producing scaffolds without severe thermal degradation.

[Effect of spatial location on the generality of block-wise conflict adaptation between different types of scripts].

PubMed

Watanabe, Yurina; Yoshizaki, Kazuhito

2014-10-01

This study aimed to investigate the generality of conflict adaptation associated with block-wise conflict frequency between two types of stimulus scripts (Kanji and Hiragana). To this end, we examined whether the modulation of the compatibility effect with one type of script depending on block-wise conflict frequency (75% versus 25% generalized to the other type of script whose block-wise conflict frequency was kept constant (50%), using the Spatial Stroop task. In Experiment 1, 16 participants were required to identify the target orientation (up or down) presented in the upper or lower visual-field. The results showed that block-wise conflict adaptation with one type of stimulus script generalized to the other. The procedure in Experiment 2 was the same as that in Experiment 1, except that the presentation location differed between the two types of stimulus scripts. We did not find a generalization from one script to the other. These results suggest that presentation location is a critical factor contributing to the generality of block-wise conflict adaptation.

In-situ ellipsometric studies of optical and surface properties of GaAs(100) at elevated temperatures

NASA Technical Reports Server (NTRS)

Yao, Huade; Snyder, Paul G.

1991-01-01

A rotating-polarizer ellipsometer was attached to an ultrahigh vacuum (UHV) chamber. A GaAs(100) sample was introduced into the UHV chamber and heated at anumber of fixed elevated temperatures, without arsenic overpressure. In-situ spectroscopic ellipsometric (SE) measurements were taken, through a pair of low-strain quartz windows, to monitor the surface changes and measure the pseudodielectric functions at elevated temperatures. Real-time data from GaAs surface covered with native oxide showed clearly the evolution of oxide desorption at approximately 580 C. In addition, surface degradation was found before and after the oxide desorption. An oxide free and smooth GaAs surface was obtained by depositing an arsenic protective coating onto a molecular beam epitaxy grown GaAs surface. The arsenic coating was evaporated immediately prior to SE measurements. A comparison showed that our room temperature data from this GaAs surface, measured in the UHV, are in good agreement with those in the literature obtained by wet-chemical etching. The surface also remained clean and smooth at higher temperatures, so that reliable temperature-dependent dielectric functions were obtained.

Initial Results of the SSPX Transient Internal Probe System for Measuring Toroidal Field Profiles

NASA Astrophysics Data System (ADS)

Holcomb, C. T.; Jarboe, T. R.; Mattick, A. T.; Hill, D. N.; McLean, H. S.; Wood, R. D.; Cellamare, V.

2000-10-01

Lawrence Livermore National Laboratory, Livermore, CA 94550, USA. The Sustained Spheromak Physics Experiment (SSPX) is using a field profile diagnostic called the Transient Internal Probe (TIP). TIP consists of a verdet-glass bullet that is used to measure the magnetic field by Faraday rotation. This probe is shot through the spheromak by a light gas gun at speeds near 2 km/s. An argon laser is aligned along the path of the probe. The light passes through the probe and is retro-reflected to an ellipsometer that measures the change in polarization angle. The measurement is spatially resolved down to the probes’ 1 cm length to within 15 Gauss. Initial testing results are given. This and future data will be used to determine the field profile for equilibrium reconstruction. TIP can also be used in conjunction with wall probes to map out toroidal mode amplitudes and phases internally. This work was performed under the auspices of US DOE by the University of California Lawrence Livermore National Laboratory under Contract No. W-7405-ENG-48.

Optical parameters of Ge15Sb5Se80 and Ge15Sb5Te80 from ellipsometric measurements

NASA Astrophysics Data System (ADS)

Abdel-Wahab, F.; Ashraf, I. M.; Alomairy, S. E.

2018-02-01

The optical properties of Ge15Sb5Se80 (GSS) and Ge15Sb5Te80 (GST) films prepared by thermal evaporation method were investigated in the photon energy range from 0.9 eV to 5 eV by using a variable-angle spectroscopic ellipsometer. Combinations of multiple Gaussian, and Tauc-Lorentz or Cody-Lorentz dispersion functions are used to fit the experimental data. The models' parameters (Lorentz oscillator amplitude, resonance energy, oscillator width, optical band gap, and Urbach energy) of both GSS and GST films were calculated. Refractive indices and extinction coefficients of the films were determined. Analysis of the absorption coefficient shows that the optical absorption edge of GSS and GST films to be 1.6 eV and 0.89 eV, respectively. Manca's relation based on mean bond energy and the bond statistics of chemically ordered model (COM) and random covalent network model (CRNM) is applied for the estimation of the optical band gap (Eg) of the investigated films. A good agreement between experimental and calculated Eg is obtained.

The study of multilayer anti-reflection coating in InSb focal plane detector

NASA Astrophysics Data System (ADS)

Zheng, Kelin; Wei, Peng; Wang, Liwen; Su, Xianjun; Wang, Haizhen

2016-10-01

In manufacturing of InSb focal plane detector, InSb chip have to be polished from backside to reduce its thickness and then be plated a layer of coating to decrease its reflection (enhance its transmittance) for infrared ray. Moreover, the anti-reflection coating has to be multilayer for more anti-reflection bandwidth. In this article, it is introduced that the optimal design of triple layer λ/4 anti-reflection coating——the anodic oxide, SiNx and MgF2. The best thickness range of each layer and its theoretical reflective index are calculated from simulation software, until the refractive index of each layer has been measured by ellipsometer. And then the transmissivity and reflectivity of the triple layer coating are measured for testing and verifying its performance on the transmittance and reflection. In the end, the anti-reflective effect of the triple layer coating and monolayer SiNx coating are respectively measured and compared by infrared focal plane array measurement system. And it is showed that this triple layer coating achieved more anti-reflection bandwidth and better anti reflective effect.

45 CFR 170.302 - General certification criteria for Complete EHRs or EHR Modules.

Code of Federal Regulations, 2013 CFR

2013-10-01

... INFORMATION TECHNOLOGY HEALTH INFORMATION TECHNOLOGY STANDARDS, IMPLEMENTATION SPECIFICATIONS, AND CERTIFICATION CRITERIA AND CERTIFICATION PROGRAMS FOR HEALTH INFORMATION TECHNOLOGY Certification Criteria for Health Information Technology § 170.302 General certification criteria for Complete EHRs or EHR Modules...

45 CFR 170.302 - General certification criteria for Complete EHRs or EHR Modules.

Code of Federal Regulations, 2014 CFR

2014-10-01

... INFORMATION TECHNOLOGY HEALTH INFORMATION TECHNOLOGY STANDARDS, IMPLEMENTATION SPECIFICATIONS, AND CERTIFICATION CRITERIA AND CERTIFICATION PROGRAMS FOR HEALTH INFORMATION TECHNOLOGY Certification Criteria for Health Information Technology § 170.302 General certification criteria for Complete EHRs or EHR Modules...

45 CFR 170.302 - General certification criteria for Complete EHRs or EHR Modules.

Code of Federal Regulations, 2011 CFR

2011-10-01

... INFORMATION TECHNOLOGY HEALTH INFORMATION TECHNOLOGY STANDARDS, IMPLEMENTATION SPECIFICATIONS, AND CERTIFICATION CRITERIA AND CERTIFICATION PROGRAMS FOR HEALTH INFORMATION TECHNOLOGY Certification Criteria for Health Information Technology § 170.302 General certification criteria for Complete EHRs or EHR Modules...

45 CFR 170.302 - General certification criteria for Complete EHRs or EHR Modules.

Code of Federal Regulations, 2012 CFR

2012-10-01

... INFORMATION TECHNOLOGY HEALTH INFORMATION TECHNOLOGY STANDARDS, IMPLEMENTATION SPECIFICATIONS, AND CERTIFICATION CRITERIA AND CERTIFICATION PROGRAMS FOR HEALTH INFORMATION TECHNOLOGY Certification Criteria for Health Information Technology § 170.302 General certification criteria for Complete EHRs or EHR Modules...

General Conformity Training Module 2.5: Proactive Role for Federal Agencies

EPA Pesticide Factsheets

Module 2.5 explains how taking a proactive role will allow a federal agency to more effectively participate in newly promulgated programs under the General Conformity Regulations, such as the emission reduction credits and the emission budgets programs.

45 CFR 170.302 - General certification criteria for Complete EHRs or EHR Modules.

Code of Federal Regulations, 2010 CFR

2010-10-01

... INFORMATION TECHNOLOGY HEALTH INFORMATION TECHNOLOGY STANDARDS, IMPLEMENTATION SPECIFICATIONS, AND CERTIFICATION CRITERIA AND CERTIFICATION PROGRAMS FOR HEALTH INFORMATION TECHNOLOGY Certification Criteria for Health Information Technology § 170.302 General certification criteria for Complete EHRs or EHR Modules...

The design of optical module of LED street lamp with non-axial symmetrical reflector

NASA Astrophysics Data System (ADS)

Lu, Ming-Jun; Chen, Chi-An; Chen, Yi-Yung; Whang, Allen Jong-Woei

2010-05-01

In recently, many research focus on the LED applications for environmental protection so a number of LED street lamps are presented. Although LED has many advantages for environmental protection, its special optical characteristics, such as intensity distribution, always limit the advantages in many applications. Therefore, we always need to do the secondary optical design for LED street lamp to replace the traditional optical designs that are designed for high-pressure sodium lamps and mercury lamps. According to the situation, we design an optical module of LED street lamp with LEDs and secondary optical design. First, the LEDs are placed on freeform reflector for the specific illuminated conditions. We design the optical module of street lamp with the two conditions that include the uniformity and the ratio of length to width in the illuminated area and without any light pollution. According to the simulation with the designed optical module, the uniformity in the illuminated area is about 0.6 that is better than the general condition, 0.3, and the ratio of length to width in the illuminated area is 3:1 in which the length is 30 meters and the width is 10 meters. Therefore, the design could let LED street lamp fits the two conditions, uniformity and ratio in the illuminated area.

A three channel telemetry system

NASA Technical Reports Server (NTRS)

Lesho, Jeffery C.; Eaton, Harry A. C.

1993-01-01

A three channel telemetry system intended for biomedical applications is described. The transmitter is implemented in a single chip using a 2 micron BiCMOS processes. The operation of the system and the test results from the latest chip are discussed. One channel is always dedicated to temperature measurement while the other two channels are generic. The generic channels carry information from transducers that are interfaced to the system through on-chip general purpose operational amplifiers. The generic channels have different bandwidths: one from dc to 250 Hz and the other from dc to 1300 Hz. Each generic channel modulates a current controlled oscillator to produce a frequency modulated signal. The two frequency modulated signals are summed and used to amplitude modulate the temperature signal which acts as a carrier. A near-field inductive link telemeters the combined signals over a short distance. The chip operates on a supply voltage anywhere from 2.5 to 3.6 Volts and draws less than 1 mA when transmitting a signal. The chip can be incorporated into ingestible, implantable and other configurations. The device can free the patient from tethered data collection systems and reduces the possibility of infection from subcutaneous leads. Data telemetry can increase patient comfort leading to a greater acceptance of monitoring.

Logarithmic M(2,p) minimal models, their logarithmic couplings, and duality

NASA Astrophysics Data System (ADS)

Mathieu, Pierre; Ridout, David

2008-10-01

A natural construction of the logarithmic extension of the M(2,p) (chiral) minimal models is presented, which generalises our previous model of percolation ( p=3). Its key aspect is the replacement of the minimal model irreducible modules by reducible ones obtained by requiring that only one of the two principal singular vectors of each module vanish. The resulting theory is then constructed systematically by repeatedly fusing these building block representations. This generates indecomposable representations of the type which signify the presence of logarithmic partner fields in the theory. The basic data characterising these indecomposable modules, the logarithmic couplings, are computed for many special cases and given a new structural interpretation. Quite remarkably, a number of them are presented in closed analytic form (for general p). These are the prime examples of "gauge-invariant" data—quantities independent of the ambiguities present in defining the logarithmic partner fields. Finally, mere global conformal invariance is shown to enforce strong constraints on the allowed spectrum: It is not possible to include modules other than those generated by the fusion of the model's building blocks. This generalises the statement that there cannot exist two effective central charges in a c=0 model. It also suggests the existence of a second "dual" logarithmic theory for each p. Such dual models are briefly discussed.

Application of stored waveform ion modulation 2D-FTICR MS/MS to the analysis of complex mixtures.

PubMed

Ross, Charles W; Simonsick, William J; Aaserud, David J

2002-09-15

Component identification of complex mixtures, whether they are from polymeric formulations or combinatorial synthesis, by conventional MS/MS techniques generally requires component separation by chromatography or mass spectrometry. An automated means of acquiring simultaneous MS/MS data from a complex mixture without prior separation is obtained from stored waveform ion modulation (SWIM) two-dimensional FTICR MS/MS. The technique applies a series of SWIFT excitation waveforms whose frequency domain magnitude spectrum is a sinusoid increasing in frequency from one waveform to the next. The controlled dissociation of the precursor ions produces an associated modulation of the product ion abundances. Fourier transformation of these abundances reveals the encoded modulation frequency from which connectivities of precursor and product ions are observed. The final result is total assignment of product ions for each precursor ion in a mixture from one automated experiment. We demonstrated the applicability of SWIM 2D-FTICR MS/MS to two diverse samples of industrial importance. We characterized structured polyester oligomers and products derived from combinatorial synthesis. Fragmentation pathways identified in standard serial ion isolation MS/MS experiments were observed for trimethylolpropane/methyl hexahydrophthalic anhydride. A 20-component sample derived from combinatorial synthesis was fragmented, and the template ion along with another key fragment ion was identified for each of the 20 components.

Feedback control of mammalian Hedgehog signaling by the Hedgehog-binding protein, Hip1, modulates Fgf signaling during branching morphogenesis of the lung

PubMed Central

Chuang, Pao-Tien; Kawcak, T'Nay; McMahon, Andrew P.

2003-01-01

Hedgehog (Hh) signaling plays a major role in multiple aspects of embryonic development. A key issue is how negative regulation of Hh signaling might contribute to generating differential responses over tens of cell diameters. In cells that respond to Hh, two proteins that are up-regulated are Patched1 (Ptch1), the Hh receptor, a general target in both invertebrate and vertebrate organisms, and Hip1, a Hh-binding protein that is vertebrate specific. To address the developmental role of Hip1 in the context of Hh signaling, we generated Hip1 mutants in the mouse. Loss of Hip1 function results in specific defects in two Hh target issues, the lung, a target of Sonic hedgehog (Shh) signaling, and the endochondral skeleton, a target of Indian hedgehog (Ihh) signaling. Hh signaling was up-regulated in Hip1 mutants, substantiating Hip1's general role in negatively regulating Hh signaling. Our studies focused on Hip1 in the lung. Here, a dynamic interaction between Hh and fibroblast growth factor (Fgf) signaling, modulated at least in part by Hip1, controls early lung branching. PMID:12569124

Feedback control of mammalian Hedgehog signaling by the Hedgehog-binding protein, Hip1, modulates Fgf signaling during branching morphogenesis of the lung.

PubMed

Chuang, Pao-Tien; Kawcak, T'Nay; McMahon, Andrew P

2003-02-01

Hedgehog (Hh) signaling plays a major role in multiple aspects of embryonic development. A key issue is how negative regulation of Hh signaling might contribute to generating differential responses over tens of cell diameters. In cells that respond to Hh, two proteins that are up-regulated are Patched1 (Ptch1), the Hh receptor, a general target in both invertebrate and vertebrate organisms, and Hip1, a Hh-binding protein that is vertebrate specific. To address the developmental role of Hip1 in the context of Hh signaling, we generated Hip1 mutants in the mouse. Loss of Hip1 function results in specific defects in two Hh target issues, the lung, a target of Sonic hedgehog (Shh) signaling, and the endochondral skeleton, a target of Indian hedgehog (Ihh) signaling. Hh signaling was up-regulated in Hip1 mutants, substantiating Hip1's general role in negatively regulating Hh signaling. Our studies focused on Hip1 in the lung. Here, a dynamic interaction between Hh and fibroblast growth factor (Fgf) signaling, modulated at least in part by Hip1, controls early lung branching.

47 CFR 2.1513 - Measurements of modulation characteristics.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 47 Telecommunication 1 2011-10-01 2011-10-01 false Measurements of modulation characteristics. 2.1513 Section 2.1513 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL FREQUENCY ALLOCATIONS... Measurements of modulation characteristics. (a) Set-up. Test of modulation characteristics are to be performed...

47 CFR 2.1513 - Measurements of modulation characteristics.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 1 2010-10-01 2010-10-01 false Measurements of modulation characteristics. 2.1513 Section 2.1513 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL FREQUENCY ALLOCATIONS... Measurements of modulation characteristics. (a) Set-up. Test of modulation characteristics are to be performed...

Modulation of localized solutions in a system of two coupled nonlinear Schrödinger equations.

PubMed

Cardoso, W B; Avelar, A T; Bazeia, D

2012-08-01

In this work we study localized solutions of a system of two coupled nonlinear Schrödinger equations, with the linear (potential) and nonlinear coefficients engendering spatial and temporal dependencies. Similarity transformations are used to convert the nonautonomous coupled equations into autonomous ones and we use the trial orbit method to help us solving them, presenting solutions in a general way. Numerical experiments are then used to verify the stability of the localized solutions.

Quasi-two-day wave coupling of the mesosphere and lower thermosphere-ionosphere in the TIME-GCM: Two-day oscillations in the ionosphere

NASA Astrophysics Data System (ADS)

Yue, Jia; Wang, Wenbin; Richmond, Arthur D.; Liu, Han-Li

2012-07-01

The Thermosphere Ionosphere Mesosphere Electrodynamics General Circulation Model (TIME-GCM) is used to simulate the quasi-two-day wave (QTDW) modulation of the ionospheric dynamo and electron density. The QTDW can directly penetrate into the lower thermosphere and modulate the neutral winds at a period of two days. The QTDW modulation of the tidal amplitudes is not evident. The QTDW in zonal and meridional winds results in a quasi-two-day oscillation (QTDO) of the dynamo electric fields at southern midlatitudes, which is mapped into the conjugate northern magnetic midlatitudes. The QTDO of the electric fields in the E region is transmitted along the magnetic field lines to the F region and leads to the QTDOs of the vertical ion drift and total electron content (TEC) at low and mid latitudes. The QTDO of the vertical ion drift near the magnetic equator leads to the 2-day oscillation of the fountain effect. The QTDO of the TEC has two peaks at ±25 magnetic latitude (Mlat) and one near the dip equator. The equatorial peak is nearly out of phase with the ones at ±25 Mlat. The vertical ion drift at midlatitudes extends the QTDW response of the TEC to midlatitudes from the Equatorial Ionospheric Anomaly (EIA). Most differently from previous reports, we discover that the QTDW winds couple into the F region ionosphere through both the fountain effect and the middle latitude dynamos.

Computational expressions for signals in frequency-modulation spectroscopy.

PubMed

Di Rosa, Michael D; Reiten, M T

2015-06-01

General expressions for the signals in frequency-modulation spectroscopy (FMS) appear in the literature but are often reduced to simple analytical equations following the assumption of a weak modulation index. This is little help to the experimentalist who wants to predict signals for modulation depths of the order of unity or greater, where strong FMS signals reside. Here, we develop general formulas for FMS signals in the case of an absorber with a Voigt line shape and then link these expressions to an example and existing numerical code for the line shape. The resulting computational recipe is easy to implement and exercised here to show where the larger FMS signals are found over the coordinates of modulation index and modulation frequency. One can also estimate from provided curves the in-phase FMS signal over a wide range of modulation parameters at either the Lorentzian-broadening or Doppler-broadening limit, or anywhere in between by interpolation.

Asymptotic Representations of Quantum Affine Superalgebras

NASA Astrophysics Data System (ADS)

Zhang, Huafeng

2017-08-01

We study representations of the quantum affine superalgebra associated with a general linear Lie superalgebra. In the spirit of Hernandez-Jimbo, we construct inductive systems of Kirillov-Reshetikhin modules based on a cyclicity result that we established previously on tensor products of these modules, and realize their inductive limits as modules over its Borel subalgebra, the so-called q-Yangian. A new generic asymptotic limit of the same inductive systems is proposed, resulting in modules over the full quantum affine superalgebra. We derive generalized Baxter's relations in the sense of Frenkel-Hernandez for representations of the full quantum group.

Would you be a geriatrician? Student career preferences and attitudes to a career in geriatric medicine.

PubMed

Ní Chróinín, Danielle; Cronin, Edel; Cullen, Walter; O'Shea, Diarmuid; Steele, Michael; Bury, Gerard; Kyne, Lorraine

2013-09-01

career intentions of medical students may impact on education and workforce planning. We sought to determine (i) career choices of senior medical students; (ii) interest in geriatric medicine; (iii) factors influencing such choices; and (iv) the impact of a 6-week Medicine in the Community module. cross-sectional survey of all senior UCD medical students, before and after completion of a 'Medicine in the Community' module, 2009-11. eighty-two per cent (274/336) completed the survey at module's end. Two-thirds (174) had chosen a future speciality, most frequently general practice (32.1%) and internal medicine (17%). Half (49.8%) believed career selection is made during medical school. Thirty-one per cent would consider a career in geriatric medicine; reasons cited were interesting field (34.5%), clinical variety (25%) and perception as emotionally rewarding (20.2%). Commonest deterrents were perceived slowness-of-pace and not wanting to work with older patients. Female students (adjusted OR: 1.89, P = 0.05) and those prioritising travel opportunities (adjusted OR: 2.77, P = 0.01) were more likely to consider geriatric medicine. Half (51.5%) reported that the community medicine module increased their interest in geriatric medicine; 91.3% that it would positively influence how they treated older patients. Students reporting a positive influence of the module were more likely to consider a career in geriatric medicine (OR: 1.62, P = 0.02). two-thirds of students had already chosen a future speciality. One-third would consider geriatric medicine. This may have important implications for workforce planning and development of geriatric medicine. Undergraduate exposure to the discipline may increase interest in geriatric medicine as a career, and positively influence management of older patients.

Thermal analysis of conceptual designs for GPHS/FPSE power systems of 250 We and 500 We

NASA Technical Reports Server (NTRS)

Mccomas, Thomas J.; Dugan, Edward T.

1991-01-01

Thermal analyses were performed for two distinct configurations of a proposed space nuclear power system which combines General Purpose Heat Source (GPHS) modules with the state of the art Free-Piston Stirling Engines (FPSEs). The two configurations correspond to systems with power levels of 250 and 500 W(sub e). The 250 W(sub e) GPHS/FPSE power system utilizes four GPHS modules and one FPSE, and the 500 W(sub e) contains eight GPHS modules and two FPSEs. The configurations of the systems and the bases for selecting the configurations are described. Brief introductory sections are included to describe the GPHS modules and free piston Stirling engines. The primary focus of the thermal analyses is on the temperature of the iridium fuel clad within the GPHS modules. A design goal temperature of 1573 K was selected as the upper limit for the fuel clad during normal operating conditions. The basis for selecting this temperature limit is discussed in detail. Results obtained from thermal analysis of the 250 W(sub e) GPHS/FPSE power system indicate fuel clad temperatures which slightly exceed the design goal temperature of 1573 K. The results are considered favorable due to the numerous conservative assumptions used in developing the thermal model and performing the thermal analysis. To demonstrate the effects of the conservatism, a brief sensitivity analysis is performed in which a few of the key system parameters are varied to determine their effect on the fuel clad temperatures. It is concluded that thermal analysis of a more detailed thermal model would be expected to yield fuel clad temperatures below the design foal temperature limiy 1573 K.

Field Effect Modulation of Heterogeneous Charge Transfer Kinetics at Back-Gated Two-Dimensional MoS2 Electrodes.

PubMed

Wang, Yan; Kim, Chang-Hyun; Yoo, Youngdong; Johns, James E; Frisbie, C Daniel

2017-12-13

The ability to improve and to modulate the heterogeneous charge transfer kinetics of two-dimensional (2D) semiconductors, such as MoS 2 , is a major challenge for electrochemical and photoelectrochemical applications of these materials. Here we report a continuous and reversible physical method for modulating the heterogeneous charge transfer kinetics at a monolayer MoS 2 working electrode supported on a SiO 2 /p-Si substrate. The heavily doped p-Si substrate serves as a back gate electrode; application of a gate voltage (V BG ) to p-Si tunes the electron occupation in the MoS 2 conduction band and shifts the conduction band edge position relative to redox species dissolved in electrolyte in contact with the front side of the MoS 2 . The gate modulation of both charge density and energy band alignment impacts charge transfer kinetics as measured by cyclic voltammetry (CV). Specifically, cyclic voltammograms combined with numerical simulations suggest that the standard heterogeneous charge transfer rate constant (k 0 ) for MoS 2 in contact with the ferrocene/ferrocenium (Fc 0/+ ) redox couple can be modulated by over 2 orders of magnitude from 4 × 10 -6 to 1 × 10 -3 cm/s, by varying V BG . In general, the field effect offers the potential to tune the electrochemical properties of 2D semiconductors, opening up new possibilities for fundamental studies of the relationship between charge transfer kinetics and independently controlled electronic band alignment and band occupation.

Scientific perspectives on music therapy.

PubMed

Hillecke, Thomas; Nickel, Anne; Bolay, Hans Volker

2005-12-01

What needs to be done on the long road to evidence-based music therapy? First of all, an adequate research strategy is required. For this purpose the general methodology for therapy research should be adopted. Additionally, music therapy needs a variety of methods of allied fields to contribute scientific findings, including mathematics, natural sciences, behavioral and social sciences, as well as the arts. Pluralism seems necessary as well as inevitable. At least two major research problems can be identified, however, that make the path stony: the problem of specificity and the problem of eclecticism. Neuroscientific research in music is giving rise to new ideas, perspectives, and methods; they seem to be promising prospects for a possible contribution to a theoretical and empirical scientific foundation for music therapy. Despite the huge heterogeneity of theoretical approaches in music therapy, an integrative model of working ingredients in music therapy is useful as a starting point for empirical studies in order to question what specifically works in music therapy. For this purpose, a heuristic model, consisting of five music therapy working factors (attention modulation, emotion modulation, cognition modulation, behavior modulation, and communication modulation) has been developed by the Center for Music Therapy Research (Viktor Dulger Institute) in Heidelberg. Evidence shows the effectiveness of music therapy for treating certain diseases, but the question of what it is in music therapy that works remains largely unanswered. The authors conclude with some questions to neuroscientists, which we hope may help elucidate relevant aspects of a possible link between the two disciplines.

Behavioral mechanisms of context fear generalization in mice

PubMed Central

Huckleberry, Kylie A.; Ferguson, Laura B.

2016-01-01

There is growing interest in generalization of learned contextual fear, driven in part by the hypothesis that mood and anxiety disorders stem from impaired hippocampal mechanisms of fear generalization and discrimination. However, there has been relatively little investigation of the behavioral and procedural mechanisms that might control generalization of contextual fear. We assessed the relative contribution of different contextual features to context fear generalization and characterized how two common conditioning protocols—foreground (uncued) and background (cued) contextual fear conditioning—affected context fear generalization. In one experiment, mice were fear conditioned in context A, and then tested for contextual fear both in A and in an alternate context created by changing a subset of A's elements. The results suggest that floor configuration and odor are more salient features than chamber shape. A second experiment compared context fear generalization in background and foreground context conditioning. Although foreground conditioning produced more context fear than background conditioning, the two procedures produced equal amounts of generalized fear. Finally, results indicated that the order of context tests (original first versus alternate first) significantly modulates context fear generalization, perhaps because the original and alternate contexts are differentially sensitive to extinction. Overall, results demonstrate that context fear generalization is sensitive to procedural variations and likely reflects the operation of multiple interacting psychological and neural mechanisms. PMID:27918275

Medical student retention of embryonic development: impact of the dimensions added by multimedia tutorials.

PubMed

Marsh, Karen R; Giffin, Bruce F; Lowrie, Donald J

2008-01-01

The purpose of this project was to develop Web-based learning modules that combine (1) animated 3D graphics; (2) 3D models that a student can manipulate independently; (3) passage of time in embryonic development; and (4) animated 2D graphics, including 2D cross-sections that represent different "slices" of the embryo, and animate in parallel. These elements were presented in two tutorials, one depicting embryonic folding and the other showing development of the nervous system after neural tube formation. The goal was to enhance the traditional teaching format-lecture combined with printed diagrams, text, and existing computer animations-with customized, guided, Web-based learning modules that surpassed existing resources. To assess module effectiveness, we compared quiz performance of control groups who attended lecture and did not use a supporting module, with study groups who used a module in addition to attending lecture. We also assessed our students' long-term retention of the material, comparing classes who had used the module with students from a previous year that had not seen the module. Our data analysis suggests that students who used a module performed better than those given only traditional resources if they used the module after they were already somewhat familiar with the material. The findings suggest that our modules-and possibly computer-assisted-instruction modules in general-are more useful if used toward the later stages of learning, rather than as an initial resource. Furthermore, our data suggest that the animation aids in long-term retention. Both medical students at the University of Cincinnati and medical faculty from across the country commented favorably on their experiences with the embryonic development modules. Copyright 2008 American Association of Anatomists

Aviation Maintenance Technology. General. G101 Aviation Mathematics and Physics. Instructor Material.

ERIC Educational Resources Information Center

Oklahoma State Board of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

These instructor materials for an aviation maintenance technology course contain three instructional modules covering safety, aviation mathematics, and aviation physics. Each module may contain an introduction and module objective, specific objectives, an instructor's module implementation guide, technical information supplements, transparency…

svdPPCS: an effective singular value decomposition-based method for conserved and divergent co-expression gene module identification.

PubMed

Zhang, Wensheng; Edwards, Andrea; Fan, Wei; Zhu, Dongxiao; Zhang, Kun

2010-06-22

Comparative analysis of gene expression profiling of multiple biological categories, such as different species of organisms or different kinds of tissue, promises to enhance the fundamental understanding of the universality as well as the specialization of mechanisms and related biological themes. Grouping genes with a similar expression pattern or exhibiting co-expression together is a starting point in understanding and analyzing gene expression data. In recent literature, gene module level analysis is advocated in order to understand biological network design and system behaviors in disease and life processes; however, practical difficulties often lie in the implementation of existing methods. Using the singular value decomposition (SVD) technique, we developed a new computational tool, named svdPPCS (SVD-based Pattern Pairing and Chart Splitting), to identify conserved and divergent co-expression modules of two sets of microarray experiments. In the proposed methods, gene modules are identified by splitting the two-way chart coordinated with a pair of left singular vectors factorized from the gene expression matrices of the two biological categories. Importantly, the cutoffs are determined by a data-driven algorithm using the well-defined statistic, SVD-p. The implementation was illustrated on two time series microarray data sets generated from the samples of accessory gland (ACG) and malpighian tubule (MT) tissues of the line W118 of M. drosophila. Two conserved modules and six divergent modules, each of which has a unique characteristic profile across tissue kinds and aging processes, were identified. The number of genes contained in these models ranged from five to a few hundred. Three to over a hundred GO terms were over-represented in individual modules with FDR < 0.1. One divergent module suggested the tissue-specific relationship between the expressions of mitochondrion-related genes and the aging process. This finding, together with others, may be of biological significance. The validity of the proposed SVD-based method was further verified by a simulation study, as well as the comparisons with regression analysis and cubic spline regression analysis plus PAM based clustering. svdPPCS is a novel computational tool for the comparative analysis of transcriptional profiling. It especially fits the comparison of time series data of related organisms or different tissues of the same organism under equivalent or similar experimental conditions. The general scheme can be directly extended to the comparisons of multiple data sets. It also can be applied to the integration of data sets from different platforms and of different sources.

New evidence and impact of electron transport non-linearities based on new perturbative inter-modulation analysis

NASA Astrophysics Data System (ADS)

van Berkel, M.; Kobayashi, T.; Igami, H.; Vandersteen, G.; Hogeweij, G. M. D.; Tanaka, K.; Tamura, N.; Zwart, H. J.; Kubo, S.; Ito, S.; Tsuchiya, H.; de Baar, M. R.; LHD Experiment Group

2017-12-01

A new methodology to analyze non-linear components in perturbative transport experiments is introduced. The methodology has been experimentally validated in the Large Helical Device for the electron heat transport channel. Electron cyclotron resonance heating with different modulation frequencies by two gyrotrons has been used to directly quantify the amplitude of the non-linear component at the inter-modulation frequencies. The measurements show significant quadratic non-linear contributions and also the absence of cubic and higher order components. The non-linear component is analyzed using the Volterra series, which is the non-linear generalization of transfer functions. This allows us to study the radial distribution of the non-linearity of the plasma and to reconstruct linear profiles where the measurements were not distorted by non-linearities. The reconstructed linear profiles are significantly different from the measured profiles, demonstrating the significant impact that non-linearity can have.

On the role of the optimization algorithm of RapidArc(®) volumetric modulated arc therapy on plan quality and efficiency.

PubMed

Vanetti, Eugenio; Nicolini, Giorgia; Nord, Janne; Peltola, Jarkko; Clivio, Alessandro; Fogliata, Antonella; Cozzi, Luca

2011-11-01

The RapidArc volumetric modulated arc therapy (VMAT) planning process is based on a core engine, the so-called progressive resolution optimizer (PRO). This is the optimization algorithm used to determine the combination of field shapes, segment weights (with dose rate and gantry speed variations), which best approximate the desired dose distribution in the inverse planning problem. A study was performed to assess the behavior of two versions of PRO. These two versions mostly differ in the way continuous variables describing the modulated arc are sampled into discrete control points, in the planning efficiency and in the presence of some new features. The analysis aimed to assess (i) plan quality, (ii) technical delivery aspects, (iii) agreement between delivery and calculations, and (iv) planning efficiency of the two versions. RapidArc plans were generated for four groups of patients (five patients each): anal canal, advanced lung, head and neck, and multiple brain metastases and were designed to test different levels of planning complexity and anatomical features. Plans from optimization with PRO2 (first generation of RapidArc optimizer) were compared against PRO3 (second generation of the algorithm). Additional plans were optimized with PRO3 using new features: the jaw tracking, the intermediate dose and the air cavity correction options. Results showed that (i) plan quality was generally improved with PRO3 and, although not for all parameters, some of the scored indices showed a macroscopic improvement with PRO3. (ii) PRO3 optimization leads to simpler patterns of the dynamic parameters particularly for dose rate. (iii) No differences were observed between the two algorithms in terms of pretreatment quality assurance measurements and (iv) PRO3 optimization was generally faster, with a time reduction of a factor approximately 3.5 with respect to PRO2. These results indicate that PRO3 is either clinically beneficial or neutral in terms of dosimetric quality while it showed significant advantages in speed and technical aspects.

33-Foot-Diameter Space Station Leading to Space Base

NASA Technical Reports Server (NTRS)

1969-01-01

This picture illustrates a concept of a 33-Foot-Diameter Space Station Leading to a Space Base. In-house work of the Marshall Space Flight Center, as well as a Phase B contract with the McDornel Douglas Astronautics Company, resulted in a preliminary design for a space station in 1969 and l970. The Marshall-McDonnel Douglas approach envisioned the use of two common modules as the core configuration of a 12-man space station. Each common module was 33 feet in diameter and 40 feet in length and provided the building blocks, not only for the space station, but also for a 50-man space base. Coupled together, the two modules would form a four-deck facility: two decks for laboratories and two decks for operations and living quarters. Zero-gravity would be the normal mode of operation, although the station would have an artificial gravity capability. This general-purpose orbital facility was to provide wide-ranging research capabilities. The design of the facility was driven by the need to accommodate a broad spectrum of activities in support of astronomy, astrophysics, aerospace medicine, biology, materials processing, space physics, and space manufacturing. To serve the needs of Earth observations, the station was to be placed in a 242-nautical-mile orbit at a 55-degree inclination. An Intermediate-21 vehicle (comprised of Saturn S-IC and S-II stages) would have launched the station in 1977.

Space Base Concept

NASA Technical Reports Server (NTRS)

1970-01-01

This is an illustration of the Space Base concept. In-house work of the Marshall Space Flight Center, as well as a Phase B contract with the McDornel Douglas Astronautics Company, resulted in a preliminary design for a space station in 1969 and l970. The Marshall-McDonnel Douglas approach envisioned the use of two common modules as the core configuration of a 12-man space station. Each common module was 33 feet in diameter and 40 feet in length and provided the building blocks, not only for the space station, but also for a 50-man space base. Coupled together, the two modules would form a four-deck facility: two decks for laboratories and two decks for operations and living quarters. Zero-gravity would be the normal mode of operation, although the station would have an artificial-gravity capability. This general-purpose orbital facility was to provide wide-ranging research capabilities. The design of the facility was driven by the need to accommodate a broad spectrum of activities in support of astronomy, astrophysics, aerospace medicine, biology, materials processing, space physics, and space manufacturing. To serve the needs of Earth observations, the station was to be placed in a 242-nautical-mile orbit at a 55-degree inclination. An Intermediate-21 vehicle (comprised of Saturn S-IC and S-II stages) would have launched the station in 1977.

Space Station

NASA Image and Video Library

1969-01-01

This picture illustrates a concept of a 33-Foot-Diameter Space Station Leading to a Space Base. In-house work of the Marshall Space Flight Center, as well as a Phase B contract with the McDornel Douglas Astronautics Company, resulted in a preliminary design for a space station in 1969 and l970. The Marshall-McDonnel Douglas approach envisioned the use of two common modules as the core configuration of a 12-man space station. Each common module was 33 feet in diameter and 40 feet in length and provided the building blocks, not only for the space station, but also for a 50-man space base. Coupled together, the two modules would form a four-deck facility: two decks for laboratories and two decks for operations and living quarters. Zero-gravity would be the normal mode of operation, although the station would have an artificial gravity capability. This general-purpose orbital facility was to provide wide-ranging research capabilities. The design of the facility was driven by the need to accommodate a broad spectrum of activities in support of astronomy, astrophysics, aerospace medicine, biology, materials processing, space physics, and space manufacturing. To serve the needs of Earth observations, the station was to be placed in a 242-nautical-mile orbit at a 55-degree inclination. An Intermediate-21 vehicle (comprised of Saturn S-IC and S-II stages) would have launched the station in 1977.

Space Station

NASA Image and Video Library

1970-01-01

This is an illustration of the Space Base concept. In-house work of the Marshall Space Flight Center, as well as a Phase B contract with the McDornel Douglas Astronautics Company, resulted in a preliminary design for a space station in 1969 and l970. The Marshall-McDonnel Douglas approach envisioned the use of two common modules as the core configuration of a 12-man space station. Each common module was 33 feet in diameter and 40 feet in length and provided the building blocks, not only for the space station, but also for a 50-man space base. Coupled together, the two modules would form a four-deck facility: two decks for laboratories and two decks for operations and living quarters. Zero-gravity would be the normal mode of operation, although the station would have an artificial-gravity capability. This general-purpose orbital facility was to provide wide-ranging research capabilities. The design of the facility was driven by the need to accommodate a broad spectrum of activities in support of astronomy, astrophysics, aerospace medicine, biology, materials processing, space physics, and space manufacturing. To serve the needs of Earth observations, the station was to be placed in a 242-nautical-mile orbit at a 55-degree inclination. An Intermediate-21 vehicle (comprised of Saturn S-IC and S-II stages) would have launched the station in 1977.

Proceedings of the Ship Control Systems Symposium (7th) Held in Bath, England on 24-27 September 1981. Volume 2

DTIC Science & Technology

1984-09-27

more effectively structured and transportable simulation program modules and powerful support software, are already in place for current use. The early...incorporates the various limits and conditions described for the major acceleration categories. (14) Speed Loop This module Is executed when the shaft speed...available, high confidence models and modules . A great leverage is gained by using generally available general purpose computers and associated support

Captured by the pain: pain steady-state evoked potentials are not modulated by selective spatial attention.

PubMed

Blöchl, Maria; Franz, Marcel; Miltner, Wolfgang H R; Weiss, Thomas

2015-04-07

Attention has been shown to affect the neural processing of pain. However, the exact mechanisms underlying this modulation remain unknown. Here, we used a new method called pain steady-state evoked potentials (PSSEPs) to investigate whether selective spatial attention affects EEG responses to tonic painful stimuli. In general, steady-state evoked potentials reflect changes in the EEG spectrum at a certain frequency that correspond to the frequency of a train of applied stimuli. In this study, high intensity transcutaneous electrical stimulation was delivered to both hands simultaneously with 31 Hz and 37 Hz, respectively. Subject׳s attention was directed to one of the two trains of stimulation in order to detect a small gap that was occasionally interspersed into the stimulus trains. Thereby, they had to ignore the stimulation applied to the other hand. Results show that PSSEPs were induced at 31 Hz and 37 Hz at frontal and central electrodes. PSSEPs occurred contralaterally to the respective hand stimulated with that frequency. Surprisingly, the magnitude of PSSEPs was not modulated by spatial attention towards one of the two stimuli. Our results indicate that attention can hardly be shifted between two simultaneously applied tonic painful stimulations. Copyright © 2015 Elsevier B.V. All rights reserved.

IAC level "O" program development

NASA Technical Reports Server (NTRS)

Vos, R. G.

1982-01-01

The current status of the IAC development activity is summarized. The listed prototype software and documentation was delivered, and details were planned for development of the level 1 operational system. The planned end product IAC is required to support LSST design analysis and performance evaluation, with emphasis on the coupling of required technical disciplines. The long term IAC effectively provides two distinct features: a specific set of analysis modules (thermal, structural, controls, antenna radiation performance and instrument optical performance) that will function together with the IAC supporting software in an integrated and user friendly manner; and a general framework whereby new analysis modules can readily be incorporated into IAC or be allowed to communicate with it.

Systemic medications: clinical significance in periodontics.

PubMed

Ciancio, Sebastian G

2002-05-01

Systemic medications are of value as adjuncts to periodontal therapy. These medications can be divided into two major categories: antibiotics and agents for host modulation. Antibiotics have been shown to be valuable adjuncts in specialized types of periodontal disease, such as localized and generalized aggressive periodontitis, and of possible value in severe chronic periodontitis. Antibiotics have been studied individually, in combination and in sequential therapy. Host modulators include Periostat, non-steroidal anti-inflammatory agents, alendronate (Fosamax), hormone replacement therapy and anti-arthritic medications. These agents produce their beneficial effects by a variety of mechanisms of action, including inhibition of matrix metalloproteinases, inhibition of prostaglandin production, stimulation of osteoblasts, inhibition of osteoclasts, and other anti-inflammatory mechanisms of action.

The multisensor payload 'Structura' for the observation of atmospheric night glows from the ISS board

NASA Astrophysics Data System (ADS)

Krot, Yury; Beliaev, Boris; Katkovsky, Leonid

2016-10-01

Aerospace Research Department of the Institute of Applied Physical Problems at Belarusian State University has developed a prototype of the optical payload intended for a space experiment on the ISS board. The prototype includes four optical modules for the night glows observation, in particular spatial-brightness and spectral characteristics in the altitude range of 80-320 km. Objects of the interest are emitting top layers of the atmosphere including exited OH radicals, atomic and molecular oxygen and sodium layers. The goal of the space experiment is a research of night glows over different regions of the Earth and a connection with natural disasters like earthquakes, cyclones, etc. Two optical modules for spatial distribution of atomic oxygen layers along the altitude consist of input lenses, spectral interferential filters and line CCD detectors. The optical module for registration of exited OH radical emissions is formed from CCD array spectrometer. The payload includes also a panchromatic (400-900 nm) high sensitive imaging camera for observing of the glows general picture. The optical modules of the prototype have been tested and general optical characteristics were determined in laboratory conditions. A solution of an astigmatism reducing of a concave diffraction grating and a method of the second diffraction order correction were applied and improved spectrometer's optical characteristics. Laboratory equipment and software were developed to imitate a dynamic scene of the night glows in laboratory conditions including an imitation of linear spectra and the spatial distribution of emissions.

Space Qualification Test of a-Silicon Solar Cell Modules

NASA Technical Reports Server (NTRS)

Kim, Q.; Lawton, R. A.; Manion, S. J.; Okuno, J. O.; Ruiz, R. P.; Vu, D. T.; Vu, D. T.; Kayali, S. A.; Jeffrey, F. R.

2004-01-01

The basic requirements of solar cell modules for space applications are generally described in MIL-S-83576 for the specific needs of the USAF. However, the specifications of solar cells intended for use on space terrestrial applications are not well defined. Therefore, this qualifications test effort was concentrated on critical areas specific to the microseismometer probe which is intended to be included in the Mars microprobe programs. Parameters that were evaluated included performance dependence on: illuminating angles, terrestrial temperatures, lifetime, as well as impact landing conditions. Our qualification efforts were limited to these most critical areas of concern. Most of the tested solar cell modules have met the requirements of the program except the impact tests. Surprisingly, one of the two single PIN 2 x 1 amorphous solar cell modules continued to function even after the 80000G impact tests. The output power parameters, Pout, FF, Isc and Voc, of the single PIN amorphous solar cell module were found to be 3.14 mW, 0.40, 9.98 mA and 0.78 V, respectively. These parameters are good enough to consider the solar module as a possible power source for the microprobe seismometer. Some recommendations were made to improve the usefulness of the amorphous silicon solar cell modules in space terrestrial applications, based on the results obtained from the intensive short term lab test effort.

Chaos M-ary modulation and demodulation method based on Hamilton oscillator and its application in communication.

PubMed

Fu, Yongqing; Li, Xingyuan; Li, Yanan; Yang, Wei; Song, Hailiang

2013-03-01

Chaotic communication has aroused general interests in recent years, but its communication effect is not ideal with the restriction of chaos synchronization. In this paper a new chaos M-ary digital modulation and demodulation method is proposed. By using region controllable characteristics of spatiotemporal chaos Hamilton map in phase plane and chaos unique characteristic, which is sensitive to initial value, zone mapping method is proposed. It establishes the map relationship between M-ary digital information and the region of Hamilton map phase plane, thus the M-ary information chaos modulation is realized. In addition, zone partition demodulation method is proposed based on the structure characteristic of Hamilton modulated information, which separates M-ary information from phase trajectory of chaotic Hamilton map, and the theory analysis of zone partition demodulator's boundary range is given. Finally, the communication system based on the two methods is constructed on the personal computer. The simulation shows that in high speed transmission communications and with no chaos synchronization circumstance, the proposed chaotic M-ary modulation and demodulation method has outperformed some conventional M-ary modulation methods, such as quadrature phase shift keying and M-ary pulse amplitude modulation in bit error rate. Besides, it has performance improvement in bandwidth efficiency, transmission efficiency and anti-noise performance, and the system complexity is low and chaos signal is easy to generate.

Quality of Life and Patient Satisfaction Following Male-to-Female Sex Reassignment Surgery.

PubMed

Papadopulos, Nikolaos A; Lellé, Jean-Daniel; Zavlin, Dmitry; Herschbach, Peter; Henrich, Gerhard; Kovacs, Laszlo; Ehrenberger, Benjamin; Kluger, Anna-Katharina; Machens, Hans-Guenther; Schaff, Juergen

2017-05-01

Surveys on quality of life (QOL) of male-to-female (MTF) transsexuals have found low QOL scores before and increased satisfaction scores after sex-reassignment surgery (SRS). To our knowledge, many of them lack standardized questionnaires and comparisons with normative data to evaluate different vaginoplasty techniques. To analyze patient satisfaction and QOL after SRS. Forty-seven patients participated in this study. All patients had surgery with our self-developed combined technique on average 19 months before the survey. They completed a self-developed indication-specific questionnaire concerning demographic and socioeconomic issues and postoperative satisfaction. Furthermore, a standardized self-assessment questionnaire on satisfaction and QOL (Fragen zur Lebenszufriedenheit Module [FLZ M ]; Questions on Life Satisfaction Modules ) was used. The FLZ M consists of three modules (general life satisfaction, satisfaction with health, and satisfaction with body image) with scores of weighted satisfaction for each item. Results of the general and health modules were compared with normative data. Demographics, QOL, general life satisfaction, satisfaction with health, and satisfaction with body image. The self-developed indication-specific questionnaire showed that 91% experienced an improvement of QOL. All patients stated they would undergo SRS again and did not regret it at all. Patients stated their femininity significantly increased. For the FLZ M , the sum score for general life satisfaction (P < .001) was significantly lower than the normative data, whereas the sum score of the satisfaction with health module (P = .038) did not reach statistical significance. The two modules also showed positive trends for different items. Values of the body image module showed a significant increase in satisfaction with breasts (P < .001) and genitals (P = .002). The findings of this survey emphasize the importance of SRS in the interdisciplinary gender-reassignment process. The detailed description of our combined technique could help to improve the surgical outcome and patient satisfaction of this complex and non-standardized surgery. This is the first description of a new surgical technique (combined technique) for MTF SRS. QOL was assessed by a large number of patients by standardized questionnaires and could be compared with normative data. Because this is a retrospective study, we can draw only careful conclusions for pre- and postoperative changes. Our self-developed combined surgical technique seemed to have a positive influence on QOL after SRS. Satisfaction with breasts, genitals, and femininity increased significantly and show the importance of surgical treatment as a key therapeutic option for MTF transsexuals. Papadopulos NA, Lellé J-D, Zavlin D, et al. Quality of Life and Patient Satisfaction Following Male-to-Female Sex Reassignment Surgery. J Sex Med 2017;14:721-730. Copyright © 2017 International Society for Sexual Medicine. Published by Elsevier Inc. All rights reserved.

An integrated general purpose SiPM based optical module with a high dynamic range

NASA Astrophysics Data System (ADS)

Bretz, T.; Engel, R.; Hebbeker, T.; Kemp, J.; Middendorf, L.; Peters, C.; Schumacher, J.; Šmída, R.; Veberič, D.

2018-06-01

Silicon photomultipliers (SiPMs) are semiconductor-based light-sensors offering a high gain, a mechanically and optically robust design and high photon detection efficiency. Due to these characteristics, they started to replace conventional photomultiplier tubes in many applications in recent years. This paper presents an optical module based on SiPMs designed for the application in scintillators as well as lab measurements. The module hosts the SiPM bias voltage supply and three pre-amplifiers with different gain levels to exploit the full dynamic range of the SiPMs. Two SiPMs, read-out in parallel, are equipped with light guides to increase the sensitive area. The light guides are optimized for the read-out of wavelength shifting fibers as used in many plastic scintillator detectors. The optical and electrical performance of the module is characterized in detail in laboratory measurements. Prototypes have been installed and tested in a modified version of the Scintillator Surface Detector developed for AugerPrime, the upgrade of the Pierre Auger Observatory. The SiPM module is operated in the Argentinian Pampas and first data proves its usability in such harsh environments.

The role of wine polysaccharides on salivary protein-tannin interaction: A molecular approach.

PubMed

Brandão, Elsa; Silva, Mafalda Santos; García-Estévez, Ignacio; Williams, Pascale; Mateus, Nuno; Doco, Thierry; de Freitas, Victor; Soares, Susana

2017-12-01

Polysaccharides are described to inhibit aggregation between food polyphenols and salivary proteins (SP) and may hence lead to astringency modulation. In this work, the effect of two wine polysaccharides (arabinogalactan proteins-AGPs and rhamnogalacturonan II- RGII) on SP-polyphenol interaction was evaluated. In general, both polysaccharides were effective to inhibit or reduce SP-polyphenol interaction and aggregation. They can act by two different mechanisms (ternary or competitive) depending on the SP-tannin pair. In the case of salivary P-B peptide, AGPs and RGII seem to act by a ternary mechanism, in which they surround this complex, enhancing its solubility. Concerning acidic proline-rich proteins (aPRPs), it was possible to observe both mechanisms, depending on the tannin and the polysaccharide involved. Overall, this work point out for a specific property of wine polysaccharides important to modulate this and other beverages and food astringency perception. Copyright © 2017 Elsevier Ltd. All rights reserved.

Superelement model based parallel algorithm for vehicle dynamics

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

Agrawal, O.P.; Danhof, K.J.; Kumar, R.

1994-05-01

This paper presents a superelement model based parallel algorithm for a planar vehicle dynamics. The vehicle model is made up of a chassis and two suspension systems each of which consists of an axle-wheel assembly and two trailing arms. In this model, the chassis is treated as a Cartesian element and each suspension system is treated as a superelement. The parameters associated with the superelements are computed using an inverse dynamics technique. Suspension shock absorbers and the tires are modeled by nonlinear springs and dampers. The Euler-Lagrange approach is used to develop the system equations of motion. This leads tomore » a system of differential and algebraic equations in which the constraints internal to superelements appear only explicitly. The above formulation is implemented on a multiprocessor machine. The numerical flow chart is divided into modules and the computation of several modules is performed in parallel to gain computational efficiency. In this implementation, the master (parent processor) creates a pool of slaves (child processors) at the beginning of the program. The slaves remain in the pool until they are needed to perform certain tasks. Upon completion of a particular task, a slave returns to the pool. This improves the overall response time of the algorithm. The formulation presented is general which makes it attractive for a general purpose code development. Speedups obtained in the different modules of the dynamic analysis computation are also presented. Results show that the superelement model based parallel algorithm can significantly reduce the vehicle dynamics simulation time. 52 refs.« less

A frequency and pulse-width co-modulation strategy for transcutaneous neuromuscular electrical stimulation based on sEMG time-domain features

NASA Astrophysics Data System (ADS)

Zhou, Yu-Xuan; Wang, Hai-Peng; Bao, Xue-Liang; Lü, Xiao-Ying; Wang, Zhi-Gong

2016-02-01

Objective. Surface electromyography (sEMG) is often used as a control signal in neuromuscular electrical stimulation (NMES) systems to enhance the voluntary control and proprioceptive sensory feedback of paralyzed patients. Most sEMG-controlled NMES systems use the envelope of the sEMG signal to modulate the stimulation intensity (current amplitude or pulse width) with a constant frequency. The aims of this study were to develop a strategy that co-modulates frequency and pulse width based on features of the sEMG signal and to investigate the torque-reproduction performance and the level of fatigue resistance achieved with our strategy. Approach. We examined the relationships between wrist torque and two stimulation parameters (frequency and pulse width) and between wrist torque and two sEMG time-domain features (mean absolute value (MAV) and number of slope sign changes (NSS)) in eight healthy volunteers. By using wrist torque as an intermediate variable, customized and generalized transfer functions were constructed to convert the two features of the sEMG signal into the two stimulation parameters, thereby establishing a MAV/NSS dual-coding (MNDC) algorithm. Wrist torque reproduction performance was assessed by comparing the torque generated by the algorithms with that originally recorded during voluntary contractions. Muscle fatigue was assessed by measuring the decline percentage of the peak torque and by comparing the torque time integral of the response to test stimulation trains before and after fatigue sessions. Main Results. The MNDC approach could produce a wrist torque that closely matched the voluntary wrist torque. In addition, a smaller decay in the wrist torque was observed after the MNDC-coded fatigue stimulation was applied than after stimulation using pulse-width modulation alone. Significance. Compared with pulse-width modulation stimulation strategies that are based on sEMG detection, the MNDC strategy is more effective for both voluntary muscle force reproduction and muscle fatigue reduction.

Personal Living Skills 10-20-30. Home Economics Curriculum.

ERIC Educational Resources Information Center

Alberta Dept. of Education, Edmonton.

This home economics curriculum contains 16 modules for teaching personal, family, and applied skills in high schools in Alberta. The modules may be used in courses on various levels. Each module consists of generalizations, objectives, suggested learning experiences related to resources, and a content checklist. Modules in the personal living…

Apparent Negative Reflection with the Gradient Acoustic Metasurface by Integrating Supercell Periodicity into the Generalized Law of Reflection.

PubMed

Liu, Bingyi; Zhao, Wenyu; Jiang, Yongyuan

2016-12-05

As the two dimensional version of the functional wavefront manipulation metamaterial, metasurface has become a research hot spot for engineering the wavefront at will with a subwavelength thickness. The wave scattered by the gradient metasurface, which is composed by the periodic supercells, is governed by the generalized Snell's law. However, the critical angle that derived from the generalized Snell's law circles the domain of the incident angles that allow the occurrence of the anomalous reflection and refraction, and no free space scattering waves could exist when the incident angle is beyond the critical angle. Here we theoretically demonstrate that apparent negative reflection can be realized by a gradient acoustic metasurface when the incident angle is beyond the critical angle. The underlying mechanism of the apparent negative reflection is understood as the higher order diffraction arising from the interaction between the local phase modulation and the non-local effects introduced by the supercell periodicity. The apparent negative reflection phenomena has been perfectly verified by the calculated scattered acoustic waves of the reflected gradient acoustic metasurface. This work may provide new freedom in designing functional acoustic signal modulation devices, such as acoustic isolator and acoustic illusion device.

Large-Scale functional network overlap is a general property of brain functional organization: Reconciling inconsistent fMRI findings from general-linear-model-based analyses

PubMed Central

Xu, Jiansong; Potenza, Marc N.; Calhoun, Vince D.; Zhang, Rubin; Yip, Sarah W.; Wall, John T.; Pearlson, Godfrey D.; Worhunsky, Patrick D.; Garrison, Kathleen A.; Moran, Joseph M.

2016-01-01

Functional magnetic resonance imaging (fMRI) studies regularly use univariate general-linear-model-based analyses (GLM). Their findings are often inconsistent across different studies, perhaps because of several fundamental brain properties including functional heterogeneity, balanced excitation and inhibition (E/I), and sparseness of neuronal activities. These properties stipulate heterogeneous neuronal activities in the same voxels and likely limit the sensitivity and specificity of GLM. This paper selectively reviews findings of histological and electrophysiological studies and fMRI spatial independent component analysis (sICA) and reports new findings by applying sICA to two existing datasets. The extant and new findings consistently demonstrate several novel features of brain functional organization not revealed by GLM. They include overlap of large-scale functional networks (FNs) and their concurrent opposite modulations, and no significant modulations in activity of most FNs across the whole brain during any task conditions. These novel features of brain functional organization are highly consistent with the brain’s properties of functional heterogeneity, balanced E/I, and sparseness of neuronal activity, and may help reconcile inconsistent GLM findings. PMID:27592153

Living Together in Space: The Design and Operation of the Life Support Systems on the International Space Station. Volume 1

NASA Technical Reports Server (NTRS)

Wieland, P. O.

1998-01-01

The International Space Station (ISS) incorporates elements designed and developed by an international consortium led by the United States (U.S.), and by Russia. For this cooperative effort to succeed, it is crucial that the designs and methods of design of the other partners are understood sufficiently to ensure compatibility. Environmental Control and Life Support (ECLS) is one system in which functions are performed independently on the Russian Segment (RS) and on the U.S./international segments. This document describes, in two volumes, the design and operation of the ECLS Systems (ECLSS) on board the ISS. This current volume, Volume 1, is divided into three chapters. Chapter 1 is a general overview of the ISS, describing the configuration, general requirements, and distribution of systems as related to the ECLSS, and includes discussion of the design philosophies of the partners and methods of verification of equipment. Chapter 2 describes the U.S. ECLSS and technologies in greater detail. Chapter 3 describes the ECLSS in the European Attached Pressurized Module (APM), Japanese Experiment Module (JEM), and Italian Mini-Pressurized Logistics Module (MPLM). Volume II describes the Russian ECLSS and technologies in greater detail. These documents present thorough, yet concise, descriptions of the ISS ECLSS.

Getting Down to Business: Pest Control Service, Module 28. Teacher Guide. Entrepreneurship Training Components.

ERIC Educational Resources Information Center

Colby, Pamela G.

This is the twenty-eighth in a set of 36 teacher guides to the Entrepreneurship Training modules and accompanies CE 031 084. Following an overview are general notes on use of the module. Suggested steps for module use contain suggestions on introducing the module, a brief discussion of the nine units, responses to learning activities, suggestions…

Discriminative-stimulus effects of NS9283, a nicotinic α4β2* positive allosteric modulator, in nicotine-discriminating rats.

PubMed

Mohler, Eric G; Franklin, Stanley R; Rueter, Lynne E

2014-01-01

Neuronal α4β2* nicotinic acetylcholine receptors mediate cognition, pain, and the discriminative and reinforcing effects of nicotine. In addition to traditional orthosteric agonists, α4β2* positive allosteric modulators (PAMs) have recently been identified. With increased subtype selectivity relative to agonists, PAMs administered alone or in combination with low-dose α4β2* agonists may be used as powerful tools for increasing our understanding of α4β2* pharmacology. The present experiments tested the nicotine discriminative-stimulus effects of the α4β2* PAM NS9283 (A-969933) in the presence and absence of low-dose nicotine or nicotinic subtype-selective agonist. Rats were trained to discriminate 0.4 mg/kg nicotine from saline in a two-lever drug discrimination paradigm. In subsequent generalization tests, rats were administered nicotine, the α4β2*-preferring agonist ABT-594, and NS9283, alone or in two-drug combinations. Nicotine and ABT-594 showed dose-dependent nicotine generalization. NS9283 alone resulted in a non-significant increase in nicotine-appropriate lever selection. Combination of non-effective doses of nicotine or ABT-594 with escalating doses of NS9283 resulted in a complete conversion to 100 % nicotine-appropriate choice in the case of nicotine combination and incomplete, though significant, generalization for ABT-594. The α4β2* PAM NS9283 alone did not produce nicotine-like discriminative effects, but did demonstrate dose-related increases in nicotine lever choice when combined with a non-effective dose of nicotine or the α4β2* agonist ABT-594. This finding provides confirmation of the positive allosteric modulating effect of NS9283 in a functional in vivo paradigm. NS9283 is a potentially valuable tool for studying the role of α4β2* receptors in various nicotinic acetylcholine receptor-related functions.

Passepartout Sherpa - A low-cost, reusable transportation system into the stratosphere for small experiments

NASA Astrophysics Data System (ADS)

Taraba, M.; Fauland, H.; Turetschek, T.; Stumptner, W.; Kudielka, V.; Scheer, D.; Sattler, B.; Fritz, A.; Stingl, B.; Fuchs, H.; Gubo, B.; Hettrich, S.; Hirtl, A.; Unger, E.; Soucek, A.; Frischauf, N.; Grömer, G.

2014-12-01

The Passepartout sounding balloon transportation system for low-mass (< 1200 g) experiments or hardware for validation to an altitude of 35 km is described. We present the general flight configuration, set-up of the flight control system, environmental and position sensors, power system, buoyancy considerations as well as the ground control infrastructure including recovery operations. In the telemetry and command module the integrated airborne computer is able to control the experiment, transmit telemetry and environmental data and allows for a duplex communication to a control centre for tele-commanding. The experiment module is mounted below the telemetry and command module and can either work as a standalone system or be controlled by the airborne computer. This spacing between experiment- and control unit allows for a high flexibility in the experiment design. After a parachute landing, the on-board satellite based recovery subsystems allow for a rapid tracking and recovery of the telemetry and command module and the experiment. We discuss flight data and lessons learned from two representative flights with research payloads.

Computational expressions for signals in frequency-modulation spectroscopy

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

Di Rosa, Michael D.; Reiten, M. T.

2015-05-25

In this study, general expressions for the signals in frequency-modulation spectroscopy (FMS) appear in the literature but are often reduced to simple analytical equations following the assumption of a weak modulation index. This is little help to the experimentalist who wants to predict signals for modulation depths of the order of unity or greater, where strong FMS signals reside. Here, we develop general formulas for FMS signals in the case of an absorber with a Voigt line shape and then link these expressions to an example and existing numerical code for the line shape. The resulting computational recipe is easymore » to implement and exercised here to show where the larger FMS signals are found over the coordinates of modulation index and modulation frequency. One can also estimate from provided curves the in-phase FMS signal over a wide range of modulation parameters at either the Lorentzian-broadening or Doppler-broadening limit, or anywhere in between by interpolation.« less

Pain in context: Cues predicting a reward decrease fear of movement related pain and avoidance behavior.

PubMed

Claes, Nathalie; Vlaeyen, Johan W S; Crombez, Geert

2016-09-01

Previous research shows that goal-directed behavior might be modulated by cues that predict (dis)similar outcomes. However, the literature investigating this modulation with pain outcomes is scarce. Therefore, this experiment investigated whether environmental cues predicting pain or reward modulate defensive pain responding. Forty-eight healthy participants completed a joystick movement task with two different movement orientations. Performing one movement was associated with a painful stimulus, whereas performance of another movement was associated with reward, i.e. lottery tickets. In a subsequent task, participants learned to associate three different cues withpain, reward, or neither of the two. Next, these cues were integrated in the movement task. This study demonstrates that in general, aversive cues enhance and appetitive cues reduce pain-related fear. Furthermore, we found that incongruence between the outcomes predicted by the movement and the cue results in more oscillatory behavior, i.e., participants were more willing to perform a painful movement when a cue predicting reward was simultaneously presented, and vice versa. Similarly, when given a choice, participants preferred to perform the reward movement, unless there was an incongruence between the outcomes predicted by the movements and cues. Taken together, these results provide experimental evidence that environmental cues are capable of modulating pain-related fear and avoidance behavior. Copyright © 2016 Elsevier Ltd. All rights reserved.

Stability of the sum of two solitary waves for (gDNLS) in the energy space

NASA Astrophysics Data System (ADS)

Tang, Xingdong; Xu, Guixiang

2018-03-01

In this paper, we continue the study in [18]. We use the perturbation argument, modulational analysis and the energy argument in [15,16] to show the stability of the sum of two solitary waves with weak interactions for the generalized derivative Schrödinger equation (gDNLS) in the energy space. Here (gDNLS) hasn't the Galilean transformation invariance, the pseudo-conformal invariance and the gauge transformation invariance, and the case σ > 1 we considered corresponds to the L2-supercritical case.

Recognizing Job Health Hazards. Module SH-08. Safety and Health.

ERIC Educational Resources Information Center

Center for Occupational Research and Development, Inc., Waco, TX.

This student module on recognizing job health hazards is one of 50 modules concerned with job safety and health. This module presents the four general categories of environmental conditions or stresses: chemical, physical, biological, and ergonomic. Following the introduction, 14 objectives (each keyed to a page in the text) the student is…

Focusing light through scattering media by polarization modulation based generalized digital optical phase conjugation

NASA Astrophysics Data System (ADS)

Yang, Jiamiao; Shen, Yuecheng; Liu, Yan; Hemphill, Ashton S.; Wang, Lihong V.

2017-11-01

Optical scattering prevents light from being focused through thick biological tissue at depths greater than ˜1 mm. To break this optical diffusion limit, digital optical phase conjugation (DOPC) based wavefront shaping techniques are being actively developed. Previous DOPC systems employed spatial light modulators that modulated either the phase or the amplitude of the conjugate light field. Here, we achieve optical focusing through scattering media by using polarization modulation based generalized DOPC. First, we describe an algorithm to extract the polarization map from the measured scattered field. Then, we validate the algorithm through numerical simulations and find that the focusing contrast achieved by polarization modulation is similar to that achieved by phase modulation. Finally, we build a system using an inexpensive twisted nematic liquid crystal based spatial light modulator (SLM) and experimentally demonstrate light focusing through 3-mm thick chicken breast tissue. Since the polarization modulation based SLMs are widely used in displays and are having more and more pixel counts with the prevalence of 4 K displays, these SLMs are inexpensive and valuable devices for wavefront shaping.

Influence of gravitational sympathetic stimulation on the Surgical Plethysmographic Index.

PubMed

Colombo, R; Marchi, A; Borghi, B; Fossali, T; Tobaldini, E; Guzzetti, S; Raimondi, F

2015-01-01

Surgical Plethysmographic Index (SPI), calculated from pulse photo-plethysmographic amplitude oscillations, has been proposed as a tool to measure nociception anti-nociception balance during general anesthesia, but it is affected by several confounding factor that alter the autonomic nervous system (ANS) modulation. We hypothesized that SPI may be mainly affected by sympathetic stimulation independently from nociception. We studied the effects of two sympathetic stimuli on SPI, delivered through passive head-up tilt at 45 and 90 degrees angles, in nine awake healthy adults. The sympathetic modulation was assessed by means of heart rate variability (HRV) analysis. Mean (SD) SPI significantly increased from baseline to 45 degrees [from 38.6 (13.7) to 60.8 (7.6), p<0.001)] and to 90 degrees angle tilt [82.3 (5.4), p<0.001]. The electrocardiographic mean R-to-R interval significantly shortened during both passive tilts, whereas systolic arterial pressure did not change during the study protocol. HRV changed significantly during the study protocol towards a predominance of sympathetic modulation during passive tilt. Gravitational sympathetic stimulation at two increasing angles, in absence of any painful stimuli, affects SPI in awake healthy volunteers. SPI seems to reflect the sympathetic outflow directed to peripheral vessels.

Towards a Comprehensive Computational Simulation System for Turbomachinery

NASA Technical Reports Server (NTRS)

Shih, Ming-Hsin

1994-01-01

The objective of this work is to develop algorithms associated with a comprehensive computational simulation system for turbomachinery flow fields. This development is accomplished in a modular fashion. These modules includes grid generation, visualization, network, simulation, toolbox, and flow modules. An interactive grid generation module is customized to facilitate the grid generation process associated with complicated turbomachinery configurations. With its user-friendly graphical user interface, the user may interactively manipulate the default settings to obtain a quality grid within a fraction of time that is usually required for building a grid about the same geometry with a general-purpose grid generation code. Non-Uniform Rational B-Spline formulations are utilized in the algorithm to maintain geometry fidelity while redistributing grid points on the solid surfaces. Bezier curve formulation is used to allow interactive construction of inner boundaries. It is also utilized to allow interactive point distribution. Cascade surfaces are transformed from three-dimensional surfaces of revolution into two-dimensional parametric planes for easy manipulation. Such a transformation allows these manipulated plane grids to be mapped to surfaces of revolution by any generatrix definition. A sophisticated visualization module is developed to al-low visualization for both grid and flow solution, steady or unsteady. A network module is built to allow data transferring in the heterogeneous environment. A flow module is integrated into this system, using an existing turbomachinery flow code. A simulation module is developed to combine the network, flow, and visualization module to achieve near real-time flow simulation about turbomachinery geometries. A toolbox module is developed to support the overall task. A batch version of the grid generation module is developed to allow portability and has been extended to allow dynamic grid generation for pitch changing turbomachinery configurations. Various applications with different characteristics are presented to demonstrate the success of this system.

The modules of trans-acyltransferase assembly lines redefined with a central acyl carrier protein.

PubMed

Vander Wood, Drew A; Keatinge-Clay, Adrian T

2018-06-01

Here, the term "module" is redefined for trans-acyltransferase (trans-AT) assembly lines to agree with how its domains cooperate and evolutionarily co-migrate. The key domain in both the polyketide synthase (PKS) and nonribosomal peptide synthetase (NRPS) modules of assembly lines is the acyl carrier protein (ACP). ACPs not only relay growing acyl chains through the assembly line but also collaborate with enzymes in modules, both in cis and in trans, to add a specific chemical moiety. A ketosynthase (KS) downstream of ACP often plays the role of gatekeeper, ensuring that only a single intermediate generated by the enzymes of a module is passed downstream. Bioinformatic analysis of 526 ACPs from 33 characterized trans-AT assembly lines reveals ACPs from the same module type generally clade together, reflective of the co-evolution of these domains with their cognate enzymes. While KSs downstream of ACPs from the same module type generally also clade together, KSs upstream of ACPs do not-in disagreement with the traditional definition of a module. Beyond nomenclature, the presented analysis impacts our understanding of module function, the evolution of assembly lines, pathway prediction, and assembly line engineering. © 2018 Wiley Periodicals, Inc.

MICROLESIONS OF THE INFERIOR OLIVE REDUCE VESTIBULAR MODULATION OF PURKINJE CELL COMPLEX AND SIMPLE SPIKES IN MOUSE CEREBELLUM

PubMed Central

Barmack, N.H.; Yakhnitsa, V.

2011-01-01

Cerebellar Purkinje cells have two distinct action potentials: Complex spikes (CSs) are evoked by single climbing fibers that originate from the contralateral inferior olive. Simple spikes (SSs) are often ascribed to mossy fiber---granule cell---parallel fiber inputs to Purkinje cells. Although generally accepted, this view lacks experimental support. Vestibular stimulation independently activates primary afferent mossy fibers and tertiary afferent climbing fibers that project to theuvula-nodulus (folia 8-10). CSs and SSs normally discharge antiphasically during sinusoidal roll-tilt. When CSs increase, SSs decrease. We tested the relative independence of these pathways in mice by making electrolytic microlesions of the two inferior olivary nuclei from which vestibular climbing fibers originate; the β-nucleus and dorsomedial cell column (DMCC). This reduced vestibular climbing fiber signaling to the contralateral folia 8-10, while leaving intact vestibular primary and secondary afferent mossy fibers. We recorded from Purkinje cells and interneurons in folia 8-10, identified by juxtacellular labeling with neurobiotin. Microlesions of the inferior olive increased the spontaneous discharge of SSs in contralateral folia 8-10, but blocked their modulation during vestibular stimulation. The vestibularly-evoked discharge of excitatory cerebellar interneurons (granule cells and unipolar brush cells) was not modified by olivary microlesions. The modulated discharge of stellate cells, but not Golgi cells was reduced by olivary microlesions. We conclude that vestibular modulation of CSs and SSs depends on intact climbing fibers. The absence of vestibularly-modulated SSs following olivary microlesions reflects the loss of climbing fiber-evoked stellate cell discharge. PMID:21734274

Optical solitons and modulation instability analysis of an integrable model of (2+1)-Dimensional Heisenberg ferromagnetic spin chain equation

NASA Astrophysics Data System (ADS)

Inc, Mustafa; Aliyu, Aliyu Isa; Yusuf, Abdullahi; Baleanu, Dumitru

2017-12-01

This paper addresses the nonlinear Schrödinger type equation (NLSE) in (2+1)-dimensions which describes the nonlinear spin dynamics of Heisenberg ferromagnetic spin chains (HFSC) with anisotropic and bilinear interactions in the semiclassical limit. Two integration schemes are employed to study the equation. These are the complex envelope function ansatz and the generalized tanh methods. Dark, dark-bright or combined optical and singular soliton solutions of the equation are derived. Furthermore, the modulational instability (MI) is studied based on the standard linear-stability analysis and the MI gain is got. Numerical simulation of the obtained results are analyzed with interesting figures showing the physical meaning of the solutions.

Steel Erection Safety. Module SH-39. Safety and Health.

ERIC Educational Resources Information Center

Center for Occupational Research and Development, Inc., Waco, TX.

This student module on steel erection safety is one of 50 modules concerned with job safety and health. This module identifies typical jobsite hazards encountered by steel erectors, as well as providing safe job procedures for general and specific construction activities. Following the introduction, 11 objectives (each keyed to a page in the text)…

Learning Outcomes of Factual Knowledge: A Comparison of Module and No Module Conditions

ERIC Educational Resources Information Center

IRIS Center, 2017

2017-01-01

During the 2004-2005 academic year, a study of the learning outcomes associated with the use of an IRIS Module was conducted at a large urban campus with a diverse student body. The module's content pertained to instructional accommodations for students with visual disabilities. In an introductory class aimed primarily at general and special…

Nuclear Technology. Course 32: Nondestructive Examination (NDE) Techniques II. Module 32-5, Fundamentals of Eddy Current Testing.

ERIC Educational Resources Information Center

Espy, John

This fifth in a series of six modules for a course titled Nondestructive Examination (NDE) Techniques II describes the fundamental concepts applicable to eddy current testing in general. The module follows a typical format that includes the following sections: (1) introduction, (2) module prerequisites, (3) objectives, (4) notes to…

Stereotypes of Aging. Module A-2. Block A. Basic Knowledge of the Aging Process.

ERIC Educational Resources Information Center

Harvey, Dexter; Cap, Orest

This instructional module on stereotypes of aging is one in a block of 10 modules designed to provide the human services worker who works with older adults with basic information regarding the aging process. An introduction provides an overview of the module content. A listing of general objectives follows. Three sections present informative…

Development of a Position Decoding ASIC for SPECT using Silicon Photomultiplier

NASA Astrophysics Data System (ADS)

Cho, M.; Kim, H.; Lim, K. T.; Cho, G.

2016-01-01

Single Photon Emission Computed Tomography(SPECT) is a widely used diagnosis modality for detecting metabolic diseases. In general, SPECT system is consisted of a sensor, a pre-amplifier, position decoding circuits(PDC) and a data acquisition(DAQ) system. Due to such complexity, it is quite costly to assemble SPECT system by putting discrete components together. Moreover, using discrete components would make the system rather bulky. In this work, we designed a channel module ASIC for SPECT system. This system was composed of a transimpedance amplifier(TIA), comparators and digital logics. In this particular module, a TIA was selected as a preamplifier because the decay time and the rise time are shorter than that of other preamplifier topologies. In the proposed module, the amplified pulse from the TIA was split into two separate signals and each signal was then fed into two comparators with different reference levels, e.g., a low and high level. Then an XOR gate combined the comparator outputs and the output of XOR gate was sent to the suceeding digital logic. Furthermore, the output of each component in the module is composed of a signal packet. The packet includes the information on the energy, the time and the position of the incident photon. The energy and position information of a detected radiation can be derived from the output of the D-flipflop(DFF) in the module via time-over-threshold(TOT). The timing information was measured using a delayed rising edge from the low-level referenced comparator. There are several advantages in developing the channel module ASIC. First of all, the ASIC has only digital outputs and thus a correction circuit for analog signal distortion can be neglected. In addition, it is possible to cut down the system production cost because the volume of the system can be reduced due to the compactness of ASIC. The benefits of channel module is not only limited to SPECT but also beneficial to many other radiation detecting systems.

Coherent state coding approaches the capacity of non-Gaussian bosonic channels

NASA Astrophysics Data System (ADS)

Huber, Stefan; König, Robert

2018-05-01

The additivity problem asks if the use of entanglement can boost the information-carrying capacity of a given channel beyond what is achievable by coding with simple product states only. This has recently been shown not to be the case for phase-insensitive one-mode Gaussian channels, but remains unresolved in general. Here we consider two general classes of bosonic noise channels, which include phase-insensitive Gaussian channels as special cases: these are attenuators with general, potentially non-Gaussian environment states and classical noise channels with general probabilistic noise. We show that additivity violations, if existent, are rather minor for all these channels: the maximal gain in classical capacity is bounded by a constant independent of the input energy. Our proof shows that coding by simple classical modulation of coherent states is close to optimal.

Enhancement of light absorption in polyazomethines due to plasmon excitation on randomly distributed metal nanoparticles

NASA Astrophysics Data System (ADS)

Wróbel, P.; Antosiewicz, T. J.; Stefaniuk, T.; Ciesielski, A.; Iwan, A.; Wronkowska, A. A.; Wronkowski, A.; Szoplik, T.

2015-05-01

In photovoltaic devices, metal nanoparticles embedded in a semiconductor layer allow the enhancement of solar-toelectric energy conversion efficiency due to enhanced light absorption via a prolonged optical path, enhanced electric fields near the metallic inclusions, direct injection of hot electrons, or local heating. Here we pursue the first two avenues. In the first, light scattered at an angle beyond the critical angle for reflection is coupled into the semiconductor layer and confined within such planar waveguide up to possible exciton generation. In the second, light is trapped by the excitation of localized surface plasmons on metal nanoparticles leading to enhanced near-field plasmon-exciton coupling at the peak of the plasmon resonance. We report on results of a numerical experiment on light absorption in polymer- (fullerene derivative) blends, using the 3D FDTD method, where exact optical parameters of the materials involved are taken from our recent measurements. In simulations we investigate light absorption in randomly distributed metal nanoparticles dispersed in polyazomethine-(fullerene derivative) blends, which serve as active layers in bulkheterojunction polymer solar cells. In the study Ag and Al nanoparticles of different diameters and fill factors are diffused in two air-stable aromatic polyazomethines with different chemical structures (abbreviated S9POF and S15POF) mixed with phenyl-C61-butyric acid methyl ester (PCBM) or [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM). The mixtures are spin coated on a 100 nm thick Al layer deposited on a fused silica substrate. Optical constants of the active layers are taken from spectroscopic ellipsometry and reflectance measurements using a rotating analyzer type ellipsometer with auto-retarder performed in the wavelength range from 225 nm to 2200 nm. The permittivities of Ag and Al particles of diameters from 20 to 60 nm are assumed to be equal to those measured on 100 to 200 nm thick metal films.

Comprehensive, powerful, efficient, intuitive: a new software framework for clinical imaging applications

NASA Astrophysics Data System (ADS)

Augustine, Kurt E.; Holmes, David R., III; Hanson, Dennis P.; Robb, Richard A.

2006-03-01

One of the greatest challenges for a software engineer is to create a complex application that is comprehensive enough to be useful to a diverse set of users, yet focused enough for individual tasks to be carried out efficiently with minimal training. This "powerful yet simple" paradox is particularly prevalent in advanced medical imaging applications. Recent research in the Biomedical Imaging Resource (BIR) at Mayo Clinic has been directed toward development of an imaging application framework that provides powerful image visualization/analysis tools in an intuitive, easy-to-use interface. It is based on two concepts very familiar to physicians - Cases and Workflows. Each case is associated with a unique patient and a specific set of routine clinical tasks, or a workflow. Each workflow is comprised of an ordered set of general-purpose modules which can be re-used for each unique workflow. Clinicians help describe and design the workflows, and then are provided with an intuitive interface to both patient data and analysis tools. Since most of the individual steps are common to many different workflows, the use of general-purpose modules reduces development time and results in applications that are consistent, stable, and robust. While the development of individual modules may reflect years of research by imaging scientists, new customized workflows based on the new modules can be developed extremely fast. If a powerful, comprehensive application is difficult to learn and complicated to use, it will be unacceptable to most clinicians. Clinical image analysis tools must be intuitive and effective or they simply will not be used.

Universality of modulation length and time exponents.

PubMed

Chakrabarty, Saurish; Dobrosavljević, Vladimir; Seidel, Alexander; Nussinov, Zohar

2012-10-01

We study systems with a crossover parameter λ, such as the temperature T, which has a threshold value λ(*) across which the correlation function changes from exhibiting fixed wavelength (or time period) modulations to continuously varying modulation lengths (or times). We introduce a hitherto unknown exponent ν(L) characterizing the universal nature of this crossover and compute its value in general instances. This exponent, similar to standard correlation length exponents, is obtained from motion of the poles of the momentum (or frequency) space correlation functions in the complex k-plane (or ω-plane) as the parameter λ is varied. Near the crossover (i.e., for λ→λ(*)), the characteristic modulation wave vector K(R) in the variable modulation length "phase" is related to that in the fixed modulation length "phase" q via |K(R)-q|[proportionality]|T-T(*)|(νL). We find, in general, that ν(L)=1/2. In some special instances, ν(L) may attain other rational values. We extend this result to general problems in which the eigenvalue of an operator or a pole characterizing general response functions may attain a constant real (or imaginary) part beyond a particular threshold value λ(*). We discuss extensions of this result to multiple other arenas. These include the axial next-nearest-neighbor Ising (ANNNI) model. By extending our considerations, we comment on relations pertaining not only to the modulation lengths (or times), but also to the standard correlation lengths (or times). We introduce the notion of a Josephson time scale. We comment on the presence of aperiodic "chaotic" modulations in "soft-spin" and other systems. These relate to glass-type features. We discuss applications to Fermi systems, with particular application to metal to band insulator transitions, change of Fermi surface topology, divergent effective masses, Dirac systems, and topological insulators. Both regular periodic and glassy (and spatially chaotic behavior) may be found in strongly correlated electronic systems.

Hemisphere division and its effect on selective attention: a generality examination of Lavie's load theory.

PubMed

Nishimura, Ritsuko; Yoshizaki, Kazuhito; Kato, Kimiko; Hatta, Takeshi

2009-01-01

The present study examined the role of visual presentation mode (unilateral vs. bilateral visual fields) on attentional modulation. We examined whether or not the presentation mode affects the compatibility effect, using a paradigm involving two task-relevant letter arrays. Sixteen participants identified a target letter among task-relevant letters while ignoring either a compatible or incompatible distracter letter that was presented to both hemispheres. Two letters arrays were presented to visual fields, either unilaterally or bilaterally. Results indicated that the compatibility effect was greater in bilateral than in unilateral visual field conditions. Findings support the assumption that the two hemispheres have separate attentional resources.

Two-dimensional supersonic nonlinear Schrödinger flow past an extended obstacle

NASA Astrophysics Data System (ADS)

El, G. A.; Kamchatnov, A. M.; Khodorovskii, V. V.; Annibale, E. S.; Gammal, A.

2009-10-01

Supersonic flow of a superfluid past a slender impenetrable macroscopic obstacle is studied in the framework of the two-dimensional (2D) defocusing nonlinear Schrödinger (NLS) equation. This problem is of fundamental importance as a dispersive analog of the corresponding classical gas-dynamics problem. Assuming the oncoming flow speed is sufficiently high, we asymptotically reduce the original boundary-value problem for a steady flow past a slender body to the one-dimensional dispersive piston problem described by the nonstationary NLS equation, in which the role of time is played by the stretched x coordinate and the piston motion curve is defined by the spatial body profile. Two steady oblique spatial dispersive shock waves (DSWs) spreading from the pointed ends of the body are generated in both half planes. These are described analytically by constructing appropriate exact solutions of the Whitham modulation equations for the front DSW and by using a generalized Bohr-Sommerfeld quantization rule for the oblique dark soliton fan in the rear DSW. We propose an extension of the traditional modulation description of DSWs to include the linear “ship-wave” pattern forming outside the nonlinear modulation region of the front DSW. Our analytic results are supported by direct 2D unsteady numerical simulations and are relevant to recent experiments on Bose-Einstein condensates freely expanding past obstacles.

Comparing Online and In-Person Delivery Formats of the OSHA 10-Hour General Industry Health and Safety Training for Young Workers.

PubMed

Shendell, Derek G; Milich, Lindsey J; Apostolico, Alexsandra A; Patti, Alexa A; Kelly, Siobhan

2017-05-01

Seven school districts or comprehensive high schools were enrolled in online OSHA 10-hour General Industry or Construction health and safety training via CareerSafe to determine the feasibility of online training for students, given limited resources for in-person trainings. A two-campus school district was analyzed comparing OSHA 10 for General Industry across in-person, supervisor-level teachers as authorized trainers, and online course formats. The online training courses were completed by 86 of 91 students, while another 53 of 57 students completed in-person training. Both groups completed identical OSHA-approved quizzes for "Introduction to OSHA," the initial 2-h module consistently provided in OSHA 10 courses across topics and formats. Results indicated teacher supervision was critical, and girls had higher online course completion rates, overall quiz scores, and never failed. Though both cohorts passed, in-person had significantly higher scores than online; both struggled with two questions. Online OSHA 10 for General Industry can be an efficient learning tool for students when limited resources prevent widespread availability of in-person courses.

Purification of complex samples: Implementation of a modular and reconfigurable droplet-based microfluidic platform with cascaded deterministic lateral displacement separation modules

PubMed Central

Pudda, Catherine; Boizot, François; Verplanck, Nicolas; Revol-Cavalier, Frédéric; Berthier, Jean; Thuaire, Aurélie

2018-01-01

Particle separation in microfluidic devices is a common problematic for sample preparation in biology. Deterministic lateral displacement (DLD) is efficiently implemented as a size-based fractionation technique to separate two populations of particles around a specific size. However, real biological samples contain components of many different sizes and a single DLD separation step is not sufficient to purify these complex samples. When connecting several DLD modules in series, pressure balancing at the DLD outlets of each step becomes critical to ensure an optimal separation efficiency. A generic microfluidic platform is presented in this paper to optimize pressure balancing, when DLD separation is connected either to another DLD module or to a different microfluidic function. This is made possible by generating droplets at T-junctions connected to the DLD outlets. Droplets act as pressure controllers, which perform at the same time the encapsulation of DLD sorted particles and the balance of output pressures. The optimized pressures to apply on DLD modules and on T-junctions are determined by a general model that ensures the equilibrium of the entire platform. The proposed separation platform is completely modular and reconfigurable since the same predictive model applies to any cascaded DLD modules of the droplet-based cartridge. PMID:29768490

Optimum modulation and demodulation matrices for solar polarimetry.

PubMed

del Toro Iniesta, J C; Collados, M

2000-04-01

Both temporal and/or spatial modulation are mandatory in current solar polarimetry [Appl. Opt. 24, 3893 (1985); 26, 3838 (1987)]. The modulating and demodulating processes are mathematically described by matrices O and D, respectively, on whose structure the accuracy of Stokes parameter measurements depend. We demonstrate, based on the definition of polarimetric efficiency [Instituto de Astrofísica de Canarias Internal Report (1994); ASP Conf. Ser. 184, 3 (1999)], that the maximum efficiencies of an ideal polarimeter are unity for Stokes I and for (Q(2) + U(2) + V(2))(1/2) and that this occurs if and only if O(T)O is diagonal; given a general (possibly nonideal) modulation matrix O, the optimum demodulation matrix turns out to be D = (O(T)O)(-1)O(T); and the maximum efficiencies in the nonideal case are given by the rms value of the column elements of matrix O and are reached by modulation matrices such that O(T)O is diagonal. From these analytical results we distill two recipes useful in the practical design of polarimeters. Their usefulness is illustrated by discussing cases of currently available solar polarimeters. Although specifically devoted to solar polarimetry, the results here may be applied in practically all other branches of science for which polarimetric measurements are needed.

The EAL domain protein YciR acts as a trigger enzyme in a c-di-GMP signalling cascade in E. coli biofilm control

PubMed Central

Lindenberg, Sandra; Klauck, Gisela; Pesavento, Christina; Klauck, Eberhard; Hengge, Regine

2013-01-01

C-di-GMP—which is produced by diguanylate cyclases (DGC) and degraded by specific phosphodiesterases (PDEs)—is a ubiquitous second messenger in bacterial biofilm formation. In Escherichia coli, several DGCs (YegE, YdaM) and PDEs (YhjH, YciR) and the MerR-like transcription factor MlrA regulate the transcription of csgD, which encodes a biofilm regulator essential for producing amyloid curli fibres of the biofilm matrix. Here, we demonstrate that this system operates as a signalling cascade, in which c-di-GMP controlled by the DGC/PDE pair YegE/YhjH (module I) regulates the activity of the YdaM/YciR pair (module II). Via multiple direct interactions, the two module II proteins form a signalling complex with MlrA. YciR acts as a connector between modules I and II and functions as a trigger enzyme: its direct inhibition of the DGC YdaM is relieved when it binds and degrades c-di-GMP generated by module I. As a consequence, YdaM then generates c-di-GMP and—by direct and specific interaction—activates MlrA to stimulate csgD transcription. Trigger enzymes may represent a general principle in local c-di-GMP signalling. PMID:23708798

Preliminary Evaluation of a New Cosmology Curriculum

NASA Astrophysics Data System (ADS)

Coble, Kimberly A.; Martin, Dominique; Hayes, Patrycia; Targett, Tom; Bailey, Janelle M.; Cominsky, Lynn R.

2015-01-01

Informed by our research on student understanding of cosmology, The Big Ideas in Cosmology is an immersive set of web-based learning modules that integrates text, figures, and visualizations with short and long interactive tasks and real cosmological data. This enables the transformation of general education astronomy and cosmology classes from primarily lecture and book-based courses to a more engaging format that builds important STEM skills.During the spring 2014 semester, we field-tested a subset of chapters with the general education astronomy and cosmology classes at Sonoma State University in a flipped-classroom format. We administered pre and post content and attitude assessments in the two flipped classes as well as two lecture classes. The majority of cosmology students had taken astronomy before whereas the astronomy students had not.When switching to an active mode of learning (e.g., flipped classroom instead of lecture), many instructors report pushback from students. We saw this effect from students in course evaluations, who reported dissatisfaction with "having to do more work." However, the students in the flipped section in astronomy made greater gains on the multiple choice content assessment than the students in either of the two lecture sections. On the attitude assessment (the CLASS), the cosmology students made a small shift toward more expert-like opinions. Preliminary results from open-ended content surveys indicate that, prior to instruction, students had difficulty answering 'why' or 'how do we know' questions; that post-instruction, students are less likely to respond "I don't know" or to leave an answer blank; and that students using the modules made gains in their content knowledge.Module development was supported by NASA ROSES E/PO Grant #NNXl0AC89G, the Illinois Space Grant Consortium, the Fermi E/PO program, Sonoma State University's Space Science Education and Public Outreach Group, and Great River Technology/Kendall-Hunt Publishing.

Relative Humidity in Limited Streamer Tubes for Stanford Linear Accelerator Center's BaBar Detector

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

Lang, M.I.; /MIT; Convery, M.

2005-12-15

The BABAR Detector at the Stanford Linear Accelerator Center studies the decay of B mesons created in e{sup +}e{sup -} collisions. The outermost layer of the detector, used to detect muons and neutral hadrons created during this process, is being upgraded from Resistive Plate Chambers (RPCs) to Limited Streamer Tubes (LSTs). The standard-size LST tube consists of eight cells, where a silver-plated wire runs down the center of each. A large potential difference is placed between the wires and ground. Gas flows through a series of modules connected with tubing, typically four. LSTs must be carefully tested before installation, asmore » it will be extremely difficult to repair any damage once installed in the detector. In the testing process, the count rate in most modules showed was stable and consistent with cosmic ray rate over an approximately 500 V operating range between 5400 to 5900 V. The count in some modules, however, was shown to unexpectedly spike near the operation point. In general, the modules through which the gas first flows did not show this problem, but those further along the gas chain were much more likely to do so. The suggestion was that this spike was due to higher humidity in the modules furthest from the fresh, dry inflowing gas, and that the water molecules in more humid modules were adversely affecting the modules' performance. This project studied the effect of humidity in the modules, using a small capacitive humidity sensor (Honeywell). The sensor provided a humidity-dependent output voltage, as well as a temperature measurement from a thermistor. A full-size hygrometer (Panametrics) was used for testing and calibrating the Honeywell sensors. First the relative humidity of the air was measured. For the full calibration, a special gas-mixing setup was used, where relative humidity of the LST gas mixture could be varied from almost dry to almost fully saturated. With the sensor calibrated, a set of sensors was used to measure humidity vs. time in the LSTs. The sensors were placed in two sets of LST modules, one gas line flowing through each set. These modules were tested for count rate v. voltage while simultaneously measuring relative humidity in each module. One set produced expected readings, while the other showed the spike in count rate. The relative humidity in the two sets of modules looked very similar, but it rose significantly for modules further along the gas chain.« less

Chocolate matrix factors modulate the pharmacokinetic behavior of cocoa flavan-3-ol phase II metabolites following oral consumption by Sprague-Dawley rats.

PubMed

Neilson, Andrew P; Sapper, Teryn N; Janle, Elsa M; Rudolph, Ralf; Matusheski, Nathan V; Ferruzzi, Mario G

2010-06-09

The impact of carbohydrates and milk on the bioavailability of catechin (C) and epicatechin (EC) from chocolate has been previously studied. However, little data exist regarding potential modulation of the phase II metabolism by these chocolate matrix factors. The objectives of this study were to assess the impact of matrix composition on qualitative and quantitative profiles of circulating catechins and their metabolites following administration of commercially relevant chocolate confections. Sprague-Dawley rats were administered 1.5 g of a confection (reference dark, high sucrose, or milk chocolate) by intragastric gavage, and plasma samples were collected over 8 h. High-performance liquid chromatography-mass spectrometry analysis was performed to quantify C, EC, and their metabolites. The predominant metabolites were O-glucuronides (two metabolites) and O-Me-O-glucuronides (three metabolites). Plasma concentrations of metabolites were generally the highest for high sucrose treatment and lowest for milk treatment, while the reference dark treatment generally resulted in intermediate concentrations. The O-Me-(+/-)-C/EC-O-beta-glucuronide (peak 4) was significantly higher for the high sucrose treatment (2325 nM h) versus the milk treatment (1300 nM h). Additionally, C(MAX) values for (+/-)-C/EC-O-beta-glucuronide (peak 3) and two O-Me-(+/-)-C/EC-O-beta-glucuronides (peaks 4 and 6) were significantly higher for the high sucrose treatment (4012, 518, and 2518 nM, respectively) versus the milk treatment (2590, 240, and 1670 nM, respectively). Milk and sucrose appear to modulate both metabolism and plasma pharmacokinetics and, to a lesser extent, the overall bioavailability of catechins from chocolate confections.

Experimental results on atomic oxygen corrosion of silver

NASA Technical Reports Server (NTRS)

Fromhold, Albert T.

1988-01-01

The results of an experimental study of the reaction kinetics of silver with atomic oxygen in 10 degree increments over the temperature range of 0 to 70 C is reported. The silver specimens, of the order of 10,000 A in thickness, were prepared by thermal evaporation onto 3 inch diameter polished silicon wafers. There were later sliced into pieces having surface areas of the order of 1/4 to 1/2 square inch. Atomic oxygen was generated by a gas discharge in a commercial plasmod asher operating in the megahertz frequency range. The sample temperature within the chamber was controlled by means of a thermoelectric unit. Exposure of the silver specimens to atomic oxygen was incremental, with oxide film thickness measurements being carried out between exposures by means of an automated ellipsometer. For the early growth phase, the data can be described satisfactorily by a logarithmic growth law: the oxide film thickness increases as the logarithm of the exposure time. Furthermore, the oxidation process is thermally activated, the rate increasing with increasing temperature. However, the empirical activation energy parameter deduced from Arrhenius plots is quite low, being of the order of 0.1 eV.

Deposition of porous low-k thin films using Tween 80 porogen for ILD application in ULSI circuits

NASA Astrophysics Data System (ADS)

Mhaisagar, Yogesh S.; Kawishwar, Renuka; Joshi, Bhavana N.; Mahajan, A. M.

2012-10-01

The porous silica low-k thin films were deposited by using Sol-gel spin coating technique. The tetraethylorthosilicate (TEOS) was used as a source of Si and the porogen Tween 80 was used for the introduction of porosity of the films. The chemical bondings of porous low-k SiO2 films have been realized by using Fourier transform infrared spectroscopy (FT-IR). The appearance of stretching, bending and rocking peaks at 1075.8, 967, 426 cm-1 respectively confirms the formation of Si-O-Si network. The Refractive index (RI) and thickness of the films were determined by using ellipsometer. Further, from RI the density and porosity of the films was estimated using standard formula. As from results it's seems that the density of the films reduces after the addition of Tween 80. The lowest value of films density after the addition of Tween 80 was found to be 1.27 g/cm3. The reduction in the film density results in increase of the porosity of films due to the removal of porogen during the curing. The increase in film porosity from 6% to 45% resulted in lower in the dielectric constant to 2.58.

In situ spectroscopic ellipsometry study of low-temperature epitaxial silicon growth

NASA Astrophysics Data System (ADS)

Halagačka, L.; Foldyna, M.; Leal, R.; Roca i Cabarrocas, P.

2018-07-01

Low-temperature growth of doped epitaxial silicon layers is a promising way to reduce the cost of p-n junction formation in c-Si solar cells. In this work, we study process of highly doped epitaxial silicon layer growth using in situ spectroscopic ellipsometry. The film was deposited by plasma-enhanced chemical vapor deposition (PECVD) on a crystalline silicon substrate at a low substrate temperature of 200 °C. In the deposition process, SiF4 was used as a precursor, B2H6 as doping gas, and a hydrogen/argon mixture as carrier gas. A spectroscopic ellipsometer with a wide spectral range was used for in situ spectroscopic measurements. Since the temperature during process is 200 °C, the optical functions of silicon differ from these at room temperature and have to be adjusted. Thickness of the epitaxial silicon layer was fitted on in situ ellipsometric data. As a result we were able to determine the dynamics of epitaxial layer growth, namely initial layer formation time and epitaxial growth rate. This study opens new perspectives in understanding and monitoring the epitaxial silicon deposition processes as the model fitting can be applied directly during the growth.

Molecularly imprinted polymer based quartz crystal microbalance sensor system for sensitive and label-free detection of synthetic cannabinoids in urine.

PubMed

Battal, Dilek; Akgönüllü, Semra; Yalcin, M Serkan; Yavuz, Handan; Denizli, Adil

2018-07-15

Herein, we prepared a novel quartz crystal microbalance (QCM) sensor for synthetic cannabinoids (JWH-073, JWH-073 butanoic acid, JWH-018 and JWH-018 pentanoic acid,) detection. Firstly, the synthetic cannabinoid (SCs) imprinted (MIP) and non-imprinted (NIP) nanoparticles were synthesized by mini-emulsion polymerization system. The SCs-imprinted nanoparticles were first characterized by SEM, TEM, zeta-size and FTIR-ATR analysis and then were dropped onto the gold QCM surface. The SCs-imprinted QCM sensor was characterized by an ellipsometer, contact angle, and AFM. The limit of detection was found as 0.3, 0.45, 0.4, 0.2 pg/mL JWH-018, JWH-073, JWH-018 pentanoic acid and JWH-073 butanoic acid, respectively. The selectivity of the SCs-imprinted QCM sensor was shown by using JWH-018, JWH-018 pentanoic acid, JWH-073 and JWH-073 butanoic acid. According to the results, the SCs-imprinted QCM sensors show highly selective and sensitive in a broad range of synthetic cannabinoid concentrations (0.0005-1.0 ng/mL) in both aqueous and synthetic urine solutions. Copyright © 2018 Elsevier B.V. All rights reserved.

Optical and other property changes of M-50 bearing steel surfaces for different lubricants and additive prior to scuffing

NASA Technical Reports Server (NTRS)

Lauer, J. L.; Marxer, N.

1984-01-01

An ester lubricant base oil containing one or more standard additives to protect against wear, corrosion, and oxidation was used in an experimental ball/plate elastohydrodynamic contact under load and speed conditions such as to induce scuffing failure in short times. Both the ball and the plate were of identically treated M-50 steel. After various periods of operating time the wear track on the plate was examined with an interference microscope of plus or minus 30 A depth resolution and sometimes also with a scanning ellipsometer and an Auger spectrometer. The optically deduced surface profiles varied with wavelength, indicating the presence of surface coatings, which were confirmed by the other instruments. As scuffing was approached, a thin (approximately A) oxide layer and a carbide layer formed in the wear track in particular when tricresylphosphate antiwear additive was present in the lubricant. The rates of the formation of these layers and their reactivity toward dilute alcholic HCl depended strongly on the lubricant and additives. Based on these results suggestions for improved formulations and a test method for bearing reliability could be proposed.

On the power spectral density of quadrature modulated signals. [satellite communication

NASA Technical Reports Server (NTRS)

Yan, T. Y.

1981-01-01

The conventional (no-offset) quadriphase modulation technique suffers from the fact that hardlimiting will restore the frequency sidelobes removed by proper filtering. Thus, offset keyed quadriphase modulation techniques are often proposed for satellite communication with bandpass hardlimiting. A unified theory is developed which is capable of describing the power spectral density before and after the hardlimiting process. Using the in-phase and the quadrature phase channel with arbitrary pulse shaping, analytical results are established for generalized quadriphase modulation. In particular MSK, OPSK or the recently introduced overlapped raised cosine keying all fall into this general category. It is shown that for a linear communication channel, the power spectral density of the modulated signal remains unchanged regardless of the offset delay. Furthermore, if the in phase and the quadrature phase channel have identical pulse shapes without offset, the spectrum after bandpass hardlimiting will be identical to that of the conventional QPSK modulation. Numerical examples are given for various modulation techniques. A case of different pulse shapes in the in phase and the quadrature phase channel is also considered.

Saturn Apollo Program

NASA Image and Video Library

1970-04-01

Apollo 13 onboard photo: This view of the severely damaged Apollo 13 Service Module was photographed from the Lunar Module/Command Module following the jettison of the Service Module. As seen here, an entire panel of the Service Module was blown away by the apparent explosion of oxygen tank number two located in Sector 4 of the Service Module. Two of the three fuel cells are visible just forward (above) the heavily damaged area. Three fuel cells, two oxygen tanks, and two hydrogen tanks, are located in Sector 4. The damaged area is located above the S-band high gain anterna. Nearest the camera is the Service Propulsion System (SPS) engine and nozzle. The damage to the Service Module caused the Apollo 13 crewmen to use the Lunar Module as a lifeboat. The Lunar Module was jettisoned by the Command Module just prior to Earth re-entry.

Physiological Aspects of Aging. Module A-5. Block A. Basic Knowledge of the Aging Process.

ERIC Educational Resources Information Center

Harvey, Dexter; Cap, Orest

This instructional module on physiological aspects of aging is one in a block of 10 modules designed to provide the human services worker who works with older adults with basic information regarding the aging process. An introduction provides an overview of the module content. A listing of general objectives follows. Nine sections present…

Confusion and the Older Adult. Module A-8. Block A. Basic Knowledge of the Aging Process.

ERIC Educational Resources Information Center

Harvey, Dexter; Cap, Orest

This instructional module on confusion and the older adult is one in a block of 10 modules designed to provide the human services worker who works with older adults with basic information regarding the aging process. An introduction provides an overview of the module content. A listing of general objectives follows. Three sections present…

Occupational Home Economics Education Series. Care and Independent Living Services for Aging. Competency Based Teaching Module.

ERIC Educational Resources Information Center

Wheeler-Liston, Carol; And Others

This large training module is intended to help prepare home helpers or others who can provide direct care and can utilize resources to assist older persons. The document presents first a general discussion of the background and rationale behind a series of occupational home economics modules. In addition, the particular module on serving the aging…

General Purpose Heat Source Simulator

NASA Technical Reports Server (NTRS)

Emrich, William J., Jr.

2008-01-01

The General Purpose Heat Source (GPHS) project seeks to combine the development of an electrically heated, single GPHS module simulator with the evaluation of potential nuclear surface power systems. The simulator is designed to match the form, fit, and function of actual GPHS modules which normally generate heat through the radioactive decay of Pu238. The use of electrically heated modules rather than modules containing Pu238 facilitates the testing of the subsystems and systems without sacrificing the quantity and quality of the test data gathered. Current GPHS activities are centered on developing robust heater designs with sizes and weights which closely match those of actual Pu238 fueled GPHS blocks. Designs are being pursued which will allow operation up to 1100 C.

Nonconscious semantic processing of emotional words modulates conscious access

PubMed Central

Gaillard, Raphaël; Del Cul, Antoine; Naccache, Lionel; Vinckier, Fabien; Cohen, Laurent; Dehaene, Stanislas

2006-01-01

Whether masked words can be processed at a semantic level remains a controversial issue in cognitive psychology. Although recent behavioral studies have demonstrated masked semantic priming for number words, attempts to generalize this finding to other categories of words have failed. Here, as an alternative to subliminal priming, we introduce a sensitive behavioral method to detect nonconscious semantic processing of words. The logic of this method consists of presenting words close to the threshold for conscious perception and examining whether their semantic content modulates performance in objective and subjective tasks. Our results disclose two independent sources of modulation of the threshold for access to consciousness. First, prior conscious perception of words increases the detection rate of the same words when they are subsequently presented with stronger masking. Second, the threshold for conscious access is lower for emotional words than for neutral ones, even for words that have not been previously consciously perceived, thus implying that written words can receive nonconscious semantic processing. PMID:16648261

Error control techniques for satellite and space communications

NASA Technical Reports Server (NTRS)

Costello, Daniel J., Jr.

1991-01-01

Shannon's capacity bound shows that coding can achieve large reductions in the required signal to noise ratio per information bit (E sub b/N sub 0 where E sub b is the energy per bit and (N sub 0)/2 is the double sided noise density) in comparison to uncoded schemes. For bandwidth efficiencies of 2 bit/sym or greater, these improvements were obtained through the use of Trellis Coded Modulation and Block Coded Modulation. A method of obtaining these high efficiencies using multidimensional Multiple Phase Shift Keying (MPSK) and Quadrature Amplitude Modulation (QAM) signal sets with trellis coding is described. These schemes have advantages in decoding speed, phase transparency, and coding gain in comparison to other trellis coding schemes. Finally, a general parity check equation for rotationally invariant trellis codes is introduced from which non-linear codes for two dimensional MPSK and QAM signal sets are found. These codes are fully transparent to all rotations of the signal set.

Dual-function photonic integrated circuit for frequency octo-tupling or single-side-band modulation.

PubMed

Hasan, Mehedi; Maldonado-Basilio, Ramón; Hall, Trevor J

2015-06-01

A dual-function photonic integrated circuit for microwave photonic applications is proposed. The circuit consists of four linear electro-optic phase modulators connected optically in parallel within a generalized Mach-Zehnder interferometer architecture. The photonic circuit is arranged to have two separate output ports. A first port provides frequency up-conversion of a microwave signal from the electrical to the optical domain; equivalently single-side-band modulation. A second port provides tunable millimeter wave carriers by frequency octo-tupling of an appropriate amplitude RF carrier. The circuit exploits the intrinsic relative phases between the ports of multi-mode interference couplers to provide substantially all the static optical phases needed. The operation of the proposed dual-function photonic integrated circuit is verified by computer simulations. The performance of the frequency octo-tupling and up-conversion functions is analyzed in terms of the electrical signal to harmonic distortion ratio and the optical single side band to unwanted harmonics ratio, respectively.

Improving Students' Inquiry Skills and Self-Efficacy through Research-Inspired Modules in the General Chemistry Laboratory

ERIC Educational Resources Information Center

Winkelmann, Kurt; Baloga, Monica; Marcinkowski, Tom; Giannoulis, Christos; Anquandah, George; Cohen, Peter

2015-01-01

Research projects conducted by faculty in STEM departments served as the inspiration for a new curriculum of inquiry-based, multiweek laboratory modules in the general chemistry 1 course. The purpose of this curriculum redesign was to improve students' attitudes about chemistry as well as their self-efficacy and skills in performing inquiry…

National Training Course. Emergency Medical Technician. Paramedic. Instructor's Lesson Plans. Module IV. General Pharmacology.

ERIC Educational Resources Information Center

National Highway Traffic Safety Administration (DOT), Washington, DC.

This instructor's lesson plan guide on general pharmacology is one of fifteen modules designed for use in the training of emergency medical technicians (paramedics). Five units of study are presented: (1) the sources of drugs, drug names, solids and liquids, and the different forms in which drugs may be dispersed; (2) the action (effects) of…

Modulational instability and higher-order rogue waves with parameters modulation in a coupled integrable AB system via the generalized Darboux transformation.

PubMed

Wen, Xiao-Yong; Yan, Zhenya

2015-12-01

We study higher-order rogue wave (RW) solutions of the coupled integrable dispersive AB system (also called Pedlosky system), which describes the evolution of wave-packets in a marginally stable or unstable baroclinic shear flow in geophysical fluids. We propose its continuous-wave (CW) solutions and existent conditions for their modulation instability to form the rogue waves. A new generalized N-fold Darboux transformation (DT) is proposed in terms of the Taylor series expansion for the spectral parameter in the Darboux matrix and its limit procedure and applied to the CW solutions to generate multi-rogue wave solutions of the coupled AB system, which satisfy the general compatibility condition. The dynamical behaviors of these higher-order rogue wave solutions demonstrate both strong and weak interactions by modulating parameters, in which some weak interactions can generate the abundant triangle, pentagon structures, etc. Particularly, the trajectories of motion of peaks and depressions of profiles of the first-order RWs are explicitly analyzed. The generalized DT method used in this paper can be extended to other nonlinear integrable systems. These results may be useful for understanding the corresponding rogue-wave phenomena in fluid mechanics and related fields.

Effect of external magnetic field on the crystal growth of nano-structured Zn xMn 1- x+ yZr yFe 2-2 yO 4 thin films

NASA Astrophysics Data System (ADS)

Anjum, Safia; Rafique, M. S.; Khaleeq-ur-Rahaman, M.; Siraj, K.; Usman, Arslan; Ahsan, A.; Naseem, S.; Khan, K.

2011-06-01

Zn 0.2Mn 0.81Zr 0.01Fe 1.98O 4 and Zn 0.2Mn 0.83Zr 0.03Fe 1.94O 4 thin films with different concentrations of Mn and Zr have been deposited on single crystal n-Si (400) at room temperature (RT) by pulse laser deposition technique (PLD). The films have been deposited under two conditions: (i) with the applied external magnetic field across the propagation of the plume (ii) without applied external magnetic field ( B=0). XRD results show the films have spinel cubic structure when deposited in the presence of magnetic field. SEM and AFM observations clearly show the effect of external applied magnetic field on the growth of films in terms of small particle size, improved uniformity and lower r.m.s. roughness. Thin films deposited under the influence of external magnetic field exhibit higher magnetization as measured by the VSM. The optical band gap energy Eg, refractive index n, reflection, absorption and the thickness of the thin films were measured by spectroscopy ellipsometer. The reflection of Zn 0.2Mn 0.83Zr 0.03Fe 1.94O 4 thin films is higher than Zn 0.2Mn 0.81Zr 0.01Fe 1.98O 4 thin films due to the greater concentration of Zr. The thicknesses of the thin films under the influence of external magnetic field are larger than the films grown without field for both samples. The optical band gap energy Eg decreases with increasing film thickness. The films with external magnetic field are found highly absorbing in nature due to the larger film thickness.

Commercial/industrial photovoltaic module and array requirement study. Low-cost solar array project engineering area

NASA Technical Reports Server (NTRS)

1981-01-01

Design requirements for photovoltaic modules and arrays used in commercial and industrial applications were identified. Building codes and referenced standards were reviewed for their applicability to commercial and industrial photovoltaic array installation. Four general installation types were identified - integral (replaces roofing), direct (mounted on top of roofing), stand-off (mounted away from roofing), and rack (for flat or low slope roofs, or ground mounted). Each of the generic mounting types can be used in vertical wall mounting systems. This implies eight mounting types exist in the commercial/industrial sector. Installation costs were developed for these mounting types as a function of panel/module size. Cost drivers were identified. Studies were performed to identify optimum module shapes and sizes and operating voltage cost drivers. The general conclusion is that there are no perceived major obstacles to the use of photovoltaic modules in commercial/industrial arrays.

An Embedded Reconfigurable Logic Module

NASA Technical Reports Server (NTRS)

Tucker, Jerry H.; Klenke, Robert H.; Shams, Qamar A. (Technical Monitor)

2002-01-01

A Miniature Embedded Reconfigurable Computer and Logic (MERCAL) module has been developed and verified. MERCAL was designed to be a general-purpose, universal module that that can provide significant hardware and software resources to meet the requirements of many of today's complex embedded applications. This is accomplished in the MERCAL module by combining a sub credit card size PC in a DIMM form factor with a XILINX Spartan I1 FPGA. The PC has the ability to download program files to the FPGA to configure it for different hardware functions and to transfer data to and from the FPGA via the PC's ISA bus during run time. The MERCAL module combines, in a compact package, the computational power of a 133 MHz PC with up to 150,000 gate equivalents of digital logic that can be reconfigured by software. The general architecture and functionality of the MERCAL hardware and system software are described.

From Domain-Generality to Domain-Sensitivity: 4-Month-Olds Learn an Abstract Repetition Rule in Music That 7-Month-Olds Do Not

PubMed Central

Dawson, Colin; Gerken, LouAnn

2009-01-01

Learning must be constrained for it to lead to productive generalizations. Although biology is undoubtedly an important source of constraints, prior experience may be another, leading learners to represent input in ways that are more conducive to some generalizations than others, and/or to up- and downweight features when entertaining generalizations. In two experiments, 4-month-old and 7-month-old infants were familiarized with sequences of musical chords or tones adhering either to an AAB pattern or an ABA pattern. In both cases, the 4-month-olds learned the generalization, but the 7-month-olds did not. The success of the 4-month-olds appears to contradict an account that this type of pattern learning is the provenance of a language-specific rule-learning module. It is not yet clear what drives the age-related change, but plausible candidates include differential experience with language and music, as well as interactions between general cognitive development and stimulus complexity. PMID:19338982

Cost and logistics of implementing a tissue-based American College of Surgeons/Association of Program Directors in Surgery surgical skills curriculum for general surgery residents of all clinical years.

PubMed

Henry, Brandon; Clark, Philip; Sudan, Ranjan

2014-02-01

The cost and logistics of deploying the American College of Surgeons (ACS)/Association of Program Directors in Surgery (APDS) National Technical Skills Curriculum across all training years are not known. This information is essential for residency programs choosing to adopt similar curricula. A task force evaluated the authors' institution's existing simulation curriculum and enhanced it by implementing the ACS/APDS modules. A 35-module curriculum was administered to 35 general surgery residents across all 5 clinical years. The costs and logistics were noted, and resident satisfaction was assessed. The annual operational cost was $110,300 ($3,150 per resident). Cost per module, per resident was $940 for the cadaveric module compared with $220 and $240 for dry simulation and animal tissue-based modules, respectively. Resident satisfaction improved from 2.45 to 4.78 on a 5-point, Likert-type scale after implementing the ACS/APDS modules. The ACS/APDS skills curriculum was implemented successfully across all clinical years. Cadaveric modules were the most expensive. Animal and dry simulation modules were equivalent in cost. The addition of tissue-based modules was associated with high satisfaction. Copyright © 2014 Elsevier Inc. All rights reserved.

Workplace Math II: Math Works!

ERIC Educational Resources Information Center

Wilson, Nancy; Goschen, Claire

This learning module, a continuation of the math I module, provides review and practice of the concepts explored in the earlier module at an intermediate level involving workplace problems. The following concepts are covered: instruction in performing basic computations, using general numerical concepts such as whole numbers, fractions, decimals,…

Apparent Negative Reflection with the Gradient Acoustic Metasurface by Integrating Supercell Periodicity into the Generalized Law of Reflection

PubMed Central

Liu, Bingyi; Zhao, Wenyu; Jiang, Yongyuan

2016-01-01

As the two dimensional version of the functional wavefront manipulation metamaterial, metasurface has become a research hot spot for engineering the wavefront at will with a subwavelength thickness. The wave scattered by the gradient metasurface, which is composed by the periodic supercells, is governed by the generalized Snell’s law. However, the critical angle that derived from the generalized Snell’s law circles the domain of the incident angles that allow the occurrence of the anomalous reflection and refraction, and no free space scattering waves could exist when the incident angle is beyond the critical angle. Here we theoretically demonstrate that apparent negative reflection can be realized by a gradient acoustic metasurface when the incident angle is beyond the critical angle. The underlying mechanism of the apparent negative reflection is understood as the higher order diffraction arising from the interaction between the local phase modulation and the non-local effects introduced by the supercell periodicity. The apparent negative reflection phenomena has been perfectly verified by the calculated scattered acoustic waves of the reflected gradient acoustic metasurface. This work may provide new freedom in designing functional acoustic signal modulation devices, such as acoustic isolator and acoustic illusion device. PMID:27917909

Two-pulse control of Raman scattering in liquid methanol: The dominance of classical nonlinear optical effects

NASA Astrophysics Data System (ADS)

Spanner, Michael; Brumer, Paul

2006-02-01

Experimental results on adaptive feedback control of transient (i.e., nonimpulsive) Stokes emission in liquid methanol [Pearson and Bucksbaum, Phys. Rev. Lett. 92, 243003 (2004)] are analyzed. In the experiment, a pump pulse comprising two frequency-shifted Gaussian pulses was used to control the ratio of two Stokes emission lines by varying the relative phase ϕL between the pulses. Extending the theory of stimulated Raman scattering to accommodate two coupled levels, we show that control of this type is possible, in the strongly driven regime, using Raman coupling alone. Control via variation of ϕL is shown to also result from self- and cross-phase-modulation of the pump and Stokes pulses as well as via the focused-beam geometry of the pump pulse. In all cases, the general control mechanism is nonlinear optical modulation between the pump and the Stokes pulse; no coherent quantum interference effects are involved. Finally, although the vibrational populations are affected by the same control mechanisms that affect the Stokes spectra, the ratio of the Stokes spectra peak heights does not directly reflect the ratio of the level populations, as was assumed in the experiment.

The Internet as an informal learning environment: Assessing knowledge acquisition of science and engineering students using constructivist and objectivist formats

NASA Astrophysics Data System (ADS)

Hargis, Jace

This study examined the effects of two different instructional formats on Internet WebPages in an informal learning environment. The purpose of this study is to (a) identify optimal instructional formats for on-line learning; (b) identify the relationship between post-assessment scores and the student's gender, age or racial identity; (c) examine the effects of verbal aptitudes on learning in different formats; (d) identify relationships between computer attitudes and achievement; and (e) identify the potential power for self-regulated learning and self-efficacy on Internet WebPages. Two learning strategy modules were developed; a constructivist and an objectivist instruction module. The study program consisted of an on-line consent form; a computer attitude survey; a Motivated Strategies for Learning Questionnaire; a verbal aptitude test; a pre-assessment; instructional directions followed by the instructional module and a post-assessment. The study tested 145 post-secondary science and engineering participants from the University of Florida. Participants were randomly assigned to one of two treatment groups or a control in a pretest/posttest design. An analysis of covariance with general linear models was used to account for effects of individual difference variables and aptitude treatment interaction (ATI). This statistical procedure was used to determine the relationships among the dependent variable, the achievement on each of the formats and the independent variables, attitudes, gender, racial identity, verbal aptitudes, and self-regulated learning/self-efficacy. Significant results at alpha = .05 were found for none of these variables. However, a linear prediction of age shows that older participants scored higher on the post-assessment after completing the objectivist module. Although there were no significant differences between the learning format and the variables, there was a difference between the modules and the control. Therefore, it is possible that regardless of characteristics, science and engineering students can learn on-line technical material.

Matched-filtering generalized phase contrast using LCoS pico-projectors for beam-forming.

PubMed

Bañas, Andrew; Palima, Darwin; Glückstad, Jesper

2012-04-23

We report on a new beam-forming system for generating high intensity programmable optical spikes using so-called matched-filtering Generalized Phase Contrast (mGPC) applying two consumer handheld pico-projectors. Such a system presents a low-cost alternative for optical trapping and manipulation, optical lattices and other beam-shaping applications usually implemented with high-end spatial light modulators. Portable pico-projectors based on liquid crystal on silicon (LCoS) devices are used as binary phase-only spatial light modulators by carefully setting the appropriate polarization of the laser illumination. The devices are subsequently placed into the object and Fourier plane of a standard 4f-setup according to the mGPC spatial filtering configuration. Having a reconfigurable spatial phase filter, instead of a fixed and fabricated one, allows the beam shaper to adapt to different input phase patterns suited for different requirements. Despite imperfections in these consumer pico-projectors, the mGPC approach tolerates phase aberrations that would have otherwise been hard to overcome by standard phase projection. © 2012 Optical Society of America

Basic avionics module design for general aviation aircraft

NASA Technical Reports Server (NTRS)

Smyth, R. K.; Smyth, D. E.

1978-01-01

The design of an advanced digital avionics system (basic avionics module) for general aviation aircraft operated with a single pilot under IFR conditions is described. The microprocessor based system provided all avionic functions, including flight management, navigation, and lateral flight control. The mode selection was interactive with the pilot. The system used a navigation map data base to provide operation in the current and planned air traffic control environment. The system design included software design listings for some of the required modules. The distributed microcomputer uses the IEEE 488 bus for interconnecting the microcomputer and sensors.

Emotional modulation of visual remapping of touch.

PubMed

Cardini, Flavia; Bertini, Caterina; Serino, Andrea; Ladavas, Elisabetta

2012-10-01

The perception of tactile stimuli on the face is modulated if subjects concurrently observe a face being touched; this effect is termed "visual remapping of touch" or the VRT effect. Given the high social value of this mechanism, we investigated whether it might be modulated by specific key information processed in face-to-face interactions: facial emotional expression. In two separate experiments, participants received tactile stimuli, near the perceptual threshold, either on their right, left, or both cheeks. Concurrently, they watched several blocks of movies depicting a face with a neutral, happy, or fearful expression that was touched or just approached by human fingers (Experiment 1). Participants were asked to distinguish between unilateral and bilateral felt tactile stimulation. Tactile perception was enhanced when viewing touch toward a fearful face compared with viewing touch toward the other two expressions. In order to test whether this result can be generalized to other negative emotions or whether it is a fear-specific effect, we ran a second experiment, where participants watched movies of faces-touched or approached by fingers-with either a fearful or an angry expression (Experiment 2). In line with the first experiment, tactile perception was enhanced when subjects viewed touch toward a fearful face and not toward an angry face. Results of the present experiments are interpreted in light of different mechanisms underlying different emotions recognition, with a specific involvement of the somatosensory system when viewing a fearful expression and a resulting fear-specific modulation of the VRT effect.

Dynamic range of frontoparietal functional modulation is associated with working memory capacity limitations in older adults.

PubMed

Hakun, Jonathan G; Johnson, Nathan F

2017-11-01

Older adults tend to over-activate regions throughout frontoparietal cortices and exhibit a reduced range of functional modulation during WM task performance compared to younger adults. While recent evidence suggests that reduced functional modulation is associated with poorer task performance, it remains unclear whether reduced range of modulation is indicative of general WM capacity-limitations. In the current study, we examined whether the range of functional modulation observed over multiple levels of WM task difficulty (N-Back) predicts in-scanner task performance and out-of-scanner psychometric estimates of WM capacity. Within our sample (60-77years of age), age was negatively associated with frontoparietal modulation range. Individuals with greater modulation range exhibited more accurate N-Back performance. In addition, despite a lack of significant relationships between N-Back and complex span task performance, range of frontoparietal modulation during the N-Back significantly predicted domain-general estimates of WM capacity. Consistent with previous cross-sectional findings, older individuals with less modulation range exhibited greater activation at the lowest level of task difficulty but less activation at the highest levels of task difficulty. Our results are largely consistent with existing theories of neurocognitive aging (e.g. CRUNCH) but focus attention on dynamic range of functional modulation asa novel marker of WM capacity-limitations in older adults. Copyright © 2017 Elsevier Inc. All rights reserved.

Higher-order vector discrete rogue-wave states in the coupled Ablowitz-Ladik equations: Exact solutions and stability.

PubMed

Wen, Xiao-Yong; Yan, Zhenya; Malomed, Boris A

2016-12-01

An integrable system of two-component nonlinear Ablowitz-Ladik equations is used to construct complex rogue-wave (RW) solutions in an explicit form. First, the modulational instability of continuous waves is studied in the system. Then, new higher-order discrete two-component RW solutions of the system are found by means of a newly derived discrete version of a generalized Darboux transformation. Finally, the perturbed evolution of these RW states is explored in terms of systematic simulations, which demonstrates that tightly and loosely bound RWs are, respectively, nearly stable and strongly unstable solutions.

The neural basis of non-verbal communication-enhanced processing of perceived give-me gestures in 9-month-old girls.

PubMed

Bakker, Marta; Kaduk, Katharina; Elsner, Claudia; Juvrud, Joshua; Gustaf Gredebäck

2015-01-01

This study investigated the neural basis of non-verbal communication. Event-related potentials were recorded while 29 nine-month-old infants were presented with a give-me gesture (experimental condition) and the same hand shape but rotated 90°, resulting in a non-communicative hand configuration (control condition). We found different responses in amplitude between the two conditions, captured in the P400 ERP component. Moreover, the size of this effect was modulated by participants' sex, with girls generally demonstrating a larger relative difference between the two conditions than boys.

DESIGN OF A PATTERN RECOGNITION DIGITAL COMPUTER WITH APPLICATION TO THE AUTOMATIC SCANNING OF BUBBLE CHAMBER NEGATIVES

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

McCormick, B.H.; Narasimhan, R.

1963-01-01

The overall computer system contains three main parts: an input device, a pattern recognition unit (PRU), and a control computer. The bubble chamber picture is divided into a grid of st run. Concent 1-mm squares on the film. It is then processed in parallel in a two-dimensional array of 1024 identical processing modules (stalactites) of the PRU. The array can function as a two- dimensional shift register in which results of successive shifting operations can be accumulated. The pattern recognition process is generally controlled by a conventional arithmetic computer. (A.G.W.)

Attosecond transient absorption of argon atoms in the vacuum ultraviolet region: line energy shifts versus coherent population transfer

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

Cao, Wei; Warrick, Erika R.; Neumark, Daniel M.

Using attosecond transient absorption, the dipole response of an argon atom in the vacuum ultraviolet (VUV) region is studied when an external electromagnetic field is present. An isolated attosecond VUV pulse populates Rydberg states lying 15 eV above the argon ground state. A synchronized few-cycle near infrared (NIR) pulse modifies the oscillating dipoles of argon impulsively, leading to alterations in the VUV absorption spectra. As the NIR pulse is delayed with respect to the VUV pulse, multiple features in the absorption profile emerge simultaneously including line broadening, sideband structure, sub-cycle fast modulations, and 5-10 fs slow modulations. These features indicatemore » the coexistence of two general processes of the light-matter interaction: the energy shift of individual atomic levels and coherent population transfer between atomic eigenstates, revealing coherent superpositions. Finally, an intuitive formula is derived to treat both effects in a unifying framework, allowing one to identify and quantify the two processes in a single absorption spectrogram.« less

Attosecond transient absorption of argon atoms in the vacuum ultraviolet region: line energy shifts versus coherent population transfer

NASA Astrophysics Data System (ADS)

Cao, Wei; Warrick, Erika R.; Neumark, Daniel M.; Leone, Stephen R.

2016-01-01

Using attosecond transient absorption, the dipole response of an argon atom in the vacuum ultraviolet (VUV) region is studied when an external electromagnetic field is present. An isolated attosecond VUV pulse populates Rydberg states lying 15 eV above the argon ground state. A synchronized few-cycle near infrared (NIR) pulse modifies the oscillating dipoles of argon impulsively, leading to alterations in the VUV absorption spectra. As the NIR pulse is delayed with respect to the VUV pulse, multiple features in the absorption profile emerge simultaneously including line broadening, sideband structure, sub-cycle fast modulations, and 5-10 fs slow modulations. These features indicate the coexistence of two general processes of the light-matter interaction: the energy shift of individual atomic levels and coherent population transfer between atomic eigenstates, revealing coherent superpositions. An intuitive formula is derived to treat both effects in a unifying framework, allowing one to identify and quantify the two processes in a single absorption spectrogram.

Attosecond transient absorption of argon atoms in the vacuum ultraviolet region: line energy shifts versus coherent population transfer

DOE PAGES

Cao, Wei; Warrick, Erika R.; Neumark, Daniel M.; ...

2016-01-18

Using attosecond transient absorption, the dipole response of an argon atom in the vacuum ultraviolet (VUV) region is studied when an external electromagnetic field is present. An isolated attosecond VUV pulse populates Rydberg states lying 15 eV above the argon ground state. A synchronized few-cycle near infrared (NIR) pulse modifies the oscillating dipoles of argon impulsively, leading to alterations in the VUV absorption spectra. As the NIR pulse is delayed with respect to the VUV pulse, multiple features in the absorption profile emerge simultaneously including line broadening, sideband structure, sub-cycle fast modulations, and 5-10 fs slow modulations. These features indicatemore » the coexistence of two general processes of the light-matter interaction: the energy shift of individual atomic levels and coherent population transfer between atomic eigenstates, revealing coherent superpositions. Finally, an intuitive formula is derived to treat both effects in a unifying framework, allowing one to identify and quantify the two processes in a single absorption spectrogram.« less

Superregular breathers, characteristics of nonlinear stage of modulation instability induced by higher-order effects

PubMed Central

Zhang, Jian-Hui; Liu, Chong

2017-01-01

We study the higher-order generalized nonlinear Schrödinger (NLS) equation describing the propagation of ultrashort optical pulse in optical fibres. By using Darboux transformation, we derive the superregular breather solution that develops from a small localized perturbation. This type of solution can be used to characterize the nonlinear stage of the modulation instability (MI) of the condensate. In particular, we show some novel characteristics of the nonlinear stage of MI arising from higher-order effects: (i) coexistence of a quasi-Akhmediev breather and a multipeak soliton; (ii) two multipeak solitons propagation in opposite directions; (iii) a beating pattern followed by two multipeak solitons in the same direction. It is found that these patterns generated from a small localized perturbation do not have the analogues in the standard NLS equation. Our results enrich Zakharov’s theory of superregular breathers and could provide helpful insight on the nonlinear stage of MI in presence of the higher-order effects. PMID:28413335

Voltage-dependent gating of KCNH potassium channels lacking a covalent link between voltage-sensing and pore domains

PubMed Central

Lörinczi, Éva; Gómez-Posada, Juan Camilo; de la Peña, Pilar; Tomczak, Adam P.; Fernández-Trillo, Jorge; Leipscher, Ulrike; Stühmer, Walter; Barros, Francisco; Pardo, Luis A.

2015-01-01

Voltage-gated channels open paths for ion permeation upon changes in membrane potential, but how voltage changes are coupled to gating is not entirely understood. Two modules can be recognized in voltage-gated potassium channels, one responsible for voltage sensing (transmembrane segments S1 to S4), the other for permeation (S5 and S6). It is generally assumed that the conversion of a conformational change in the voltage sensor into channel gating occurs through the intracellular S4–S5 linker that provides physical continuity between the two regions. Using the pathophysiologically relevant KCNH family, we show that truncated proteins interrupted at, or lacking the S4–S5 linker produce voltage-gated channels in a heterologous model that recapitulate both the voltage-sensing and permeation properties of the complete protein. These observations indicate that voltage sensing by the S4 segment is transduced to the channel gate in the absence of physical continuity between the modules. PMID:25818916

Super-resolution structured illumination in optically thick specimens without fluorescent tagging

NASA Astrophysics Data System (ADS)

Hoffman, Zachary R.; DiMarzio, Charles A.

2017-11-01

This research extends the work of Hoffman et al. to provide both sectioning and super-resolution using random patterns within thick specimens. Two methods of processing structured illumination in reflectance have been developed without the need for a priori knowledge of either the optical system or the modulation patterns. We explore the use of two deconvolution algorithms that assume either Gaussian or sparse priors. This paper will show that while both methods accomplish their intended objective, the sparse priors method provides superior resolution and contrast against all tested targets, providing anywhere from ˜1.6× to ˜2× resolution enhancement. The methods developed here can reasonably be implemented to work without a priori knowledge about the patterns or point spread function. Further, all experiments are run using an incoherent light source, unknown random modulation patterns, and without the use of fluorescent tagging. These additional modifications are challenging, but the generalization of these methods makes them prime candidates for clinical application, providing super-resolved noninvasive sectioning in vivo.

Cholinergic transmission in the dorsal hippocampus modulates trace but not delay fear conditioning.

PubMed

Pang, Min-Hee; Kim, Nam-Soo; Kim, Il-Hwan; Kim, Hyun; Kim, Hyun-Taek; Choi, June-Seek

2010-09-01

Although cholinergic mechanisms have been widely implicated in learning and memory processes, few studies have investigated the specific contribution of hippocampal cholinergic transmission during trace fear conditioning, a form of associative learning involving a temporal gap between two stimuli. Microinfusions of scopolamine, a muscarinic receptor antagonist, into the dorsal hippocampus (DH) produced dose-dependent impairment in the acquisition and expression of a conditioned response (CR) following trace fear conditioning with a tone conditioned stimulus (CS) and a footshock unconditioned stimulus (US) in rats. The same infusions, however, had no effect on delay conditioning, general activity, pain sensitivity or attentional modulation. Moreover, scopolamine infusions attenuated phosphorylation of extracellular signal-regulated kinase (ERK) in the amygdala, indicating that cholinergic signals in the DH are important for trace fear conditioning. Taken together, the current study provides evidence that cholinergic neurotransmission in the DH is essential for the cellular processing of CS-US association in the amygdala when the two stimuli are temporally disconnected. Copyright 2010 Elsevier Inc. All rights reserved.

Voltage-dependent gating of KCNH potassium channels lacking a covalent link between voltage-sensing and pore domains.

PubMed

Lörinczi, Éva; Gómez-Posada, Juan Camilo; de la Peña, Pilar; Tomczak, Adam P; Fernández-Trillo, Jorge; Leipscher, Ulrike; Stühmer, Walter; Barros, Francisco; Pardo, Luis A

2015-03-30

Voltage-gated channels open paths for ion permeation upon changes in membrane potential, but how voltage changes are coupled to gating is not entirely understood. Two modules can be recognized in voltage-gated potassium channels, one responsible for voltage sensing (transmembrane segments S1 to S4), the other for permeation (S5 and S6). It is generally assumed that the conversion of a conformational change in the voltage sensor into channel gating occurs through the intracellular S4-S5 linker that provides physical continuity between the two regions. Using the pathophysiologically relevant KCNH family, we show that truncated proteins interrupted at, or lacking the S4-S5 linker produce voltage-gated channels in a heterologous model that recapitulate both the voltage-sensing and permeation properties of the complete protein. These observations indicate that voltage sensing by the S4 segment is transduced to the channel gate in the absence of physical continuity between the modules.

Voltage-dependent gating of KCNH potassium channels lacking a covalent link between voltage-sensing and pore domains

NASA Astrophysics Data System (ADS)

Lörinczi, Éva; Gómez-Posada, Juan Camilo; de La Peña, Pilar; Tomczak, Adam P.; Fernández-Trillo, Jorge; Leipscher, Ulrike; Stühmer, Walter; Barros, Francisco; Pardo, Luis A.

2015-03-01

Voltage-gated channels open paths for ion permeation upon changes in membrane potential, but how voltage changes are coupled to gating is not entirely understood. Two modules can be recognized in voltage-gated potassium channels, one responsible for voltage sensing (transmembrane segments S1 to S4), the other for permeation (S5 and S6). It is generally assumed that the conversion of a conformational change in the voltage sensor into channel gating occurs through the intracellular S4-S5 linker that provides physical continuity between the two regions. Using the pathophysiologically relevant KCNH family, we show that truncated proteins interrupted at, or lacking the S4-S5 linker produce voltage-gated channels in a heterologous model that recapitulate both the voltage-sensing and permeation properties of the complete protein. These observations indicate that voltage sensing by the S4 segment is transduced to the channel gate in the absence of physical continuity between the modules.

Frequency modulation indicator, Arnold’s web and diffusion in the Stark Quadratic-Zeeman problem

NASA Astrophysics Data System (ADS)

Cordani, Bruno

2008-11-01

We notice that the fundamental frequencies of a slightly perturbed integrable Hamiltonian system are not time-constant inside a resonance but frequency modulated, as is evident from pendulum models and wavelet analysis. Exploiting an intrinsic imprecision inherent to the numerical frequency analysis algorithm itself, hence transforming a drawback into an opportunity, we define the Frequency Modulation Indicator, a very sensitive tool in detecting where fundamental frequencies are modulated, localizing so the resonances without having to resort, as in other methods, to the integration of variational equations. For the Kepler problem, the space of the orbits with a fixed energy has the topology of the product of two 2-spheres. The perturbation Hamiltonian, averaged over the mean anomaly, has surely a maximum and a minimum, to which correspond two periodic orbits in physical space. Studying the neighbourhood of these two elliptic stable points, we are able to define adapted action-angle variables, for example, the usual but “SO(4)-rotated” Delaunay variables. The procedure, implemented in the program KEPLER, is performed transparently for the user, providing a general scheme suited for generic perturbation. The method is then applied to the Stark-Quadratic-Zeeman problem, displaying very clearly the Arnold web of the resonances. Sectioning transversely one of the resonance strips so highlighted and performing a numerical frequency analysis, one is able to locate with great precision the thin stochastic layer surrounding a separatrix. Another very long (10 8 revolutions) frequency analysis on an orbit starting here reveals, as expected, a well defined pattern, which ensures that the integration errors do not eject the point out of the layer, and moreover a very slow drift in the frequency values, clearly due to Arnold diffusion.

Insights into structure–activity relationship of GABAA receptor modulating coumarins and furanocoumarins

PubMed Central

Singhuber, Judith; Baburin, Igor; Ecker, Gerhard F.; Kopp, Brigitte; Hering, Steffen

2011-01-01

The coumarins imperatorin and osthole are known to exert anticonvulsant activity. We have therefore analyzed the modulation of GABA-induced chloride currents (IGABA) by a selection of 18 coumarin derivatives on recombinant α1β2γ2S GABAA receptors expressed in Xenopus laevis oocytes by means of the two-microelectrode voltage clamp technique. Osthole (EC50=14±1 μM) and oxypeucedanin (EC50=25±8 μM) displayed the highest efficiency with IGABA potentiation of 116±4% and 547±56%, respectively. IGABA enhancement by osthole and oxypeucedanin was not inhibited by flumazenil (1 μM) indicating an interaction with a binding site distinct from the benzodiazepine binding site. In general, prenyl residues are essential for the positive modulatory activity, while longer side chains or bulkier residues (e.g. geranyl residues) diminish IGABA modulation. Generation of a binary classification tree revealed the importance of polarisability, which is sufficient to distinguish actives from inactives. A 4-point pharmacophore model based on oxypeucedanin – comprising three hydrophobic and one aromatic feature – identified 6 out of 7 actives as hits. In summary, (oxy-)prenylated coumarin derivatives from natural origin represent new GABAA receptor modulators. PMID:21749864

Getting Down to Business: Dairy Farming, Module 6. Teacher Guide. Entrepreneurship Training Components.

ERIC Educational Resources Information Center

McBain, Susan L.

This is the sixth in a set of 36 teacher guides to the Entrepreneurship Training Modules and accompanies CE 031 040. Its purpose is to give students some idea of what it is like to own and operate a dairy farm. Following an overview are general notes on use of the module. Suggested steps for module use contain suggestions on introducing the…

Study Modules for Calculus-Based General Physics. [Includes Modules 24-26: Electric Potential; Ohm's Law; and Capacitors].

ERIC Educational Resources Information Center

Fuller, Robert G., Ed.; And Others

This is part of a series of 42 Calculus Based Physics (CBP) modules totaling about 1,000 pages. The modules include study guides, practice tests, and mastery tests for a full-year individualized course in calculus-based physics based on the Personalized System of Instruction (PSI). The units are not intended to be used without outside materials;…

Getting Down to Business: Travel Agency, Module 9. Teacher Guide. Entrepreneurship Training Components.

ERIC Educational Resources Information Center

Rassen, Rachel L.

This is the ninth in a set of 36 teacher guides to the Entrepreneurship Training modules and accompanies CE 031 046. Its purpose is to give students some idea of what it is like to own and operate a travel agency. Following an overview are general notes on use of the module. Suggested steps for module use contain suggestions on introducing the…

Health Instruction Packages: Consumer--Exercise and Rehabilitation.

ERIC Educational Resources Information Center

Hughes, Caroline; And Others

Text, illustrations and exercises are utilized in these six learning modules to instruct patients and the general public in exercise and rehabilitative techniques. The first module, "Exercise and Your Life" by Caroline Hughes, distinguishes between static and dynamic exercise and discusses the benefits of exercise. The second module,…

General Electronics Technician.

ERIC Educational Resources Information Center

Vorderstrasse, Ron; Huston, Jane, Ed.

This module follows the "Basic Electronics" module as a guide for a course preparing students for job entry or further education. It includes those additional tasks required above Basic Electronics for job entry in the electronics field. The module contains eight instructional units that cover the following topics: (1) test equipment; (2)…

Millwright Apprenticeship. Related Training Modules. 1.1-1.8 Safety.

ERIC Educational Resources Information Center

Lane Community Coll., Eugene, OR.

This packet, part of the instructional materials for the Oregon apprenticeship program for millwright training, contains eight modules covering safety. The modules provide information on the following topics: general safety, hand tool safety, power tool safety, fire safety, hygiene, safety and electricity, types of fire and fire prevention, and…

Aviation Maintenance Technology. General. G103 Fundamentals of Regulations, Publications, and Records. Instructor Material.

ERIC Educational Resources Information Center

Oklahoma State Board of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

These instructor materials for an aviation maintenance technology course contain three instructional modules. The modules cover the following topics: selecting and using regulations, publications, and records; documenting aircraft records; and exercising mechanic's privileges and limitations. Each module contains some or all of these nine basic…

Oil Spill!: An Event-Based Science Module. Teacher's Guide. Oceanography Module.

ERIC Educational Resources Information Center

Wright, Russell G.

This book is designed for middle school earth science or general science teachers to help their students learn scientific literacy through event-based science. Unlike traditional curricula, the event- based earth science module is a student-centered, interdisciplinary, inquiry-oriented program that emphasizes cooperative learning, teamwork,…

Task-discriminative space-by-time factorization of muscle activity

PubMed Central

Delis, Ioannis; Panzeri, Stefano; Pozzo, Thierry; Berret, Bastien

2015-01-01

Movement generation has been hypothesized to rely on a modular organization of muscle activity. Crucial to this hypothesis is the ability to perform reliably a variety of motor tasks by recruiting a limited set of modules and combining them in a task-dependent manner. Thus far, existing algorithms that extract putative modules of muscle activations, such as Non-negative Matrix Factorization (NMF), identify modular decompositions that maximize the reconstruction of the recorded EMG data. Typically, the functional role of the decompositions, i.e., task accomplishment, is only assessed a posteriori. However, as motor actions are defined in task space, we suggest that motor modules should be computed in task space too. In this study, we propose a new module extraction algorithm, named DsNM3F, that uses task information during the module identification process. DsNM3F extends our previous space-by-time decomposition method (the so-called sNM3F algorithm, which could assess task performance only after having computed modules) to identify modules gauging between two complementary objectives: reconstruction of the original data and reliable discrimination of the performed tasks. We show that DsNM3F recovers the task dependence of module activations more accurately than sNM3F. We also apply it to electromyographic signals recorded during performance of a variety of arm pointing tasks and identify spatial and temporal modules of muscle activity that are highly consistent with previous studies. DsNM3F achieves perfect task categorization without significant loss in data approximation when task information is available and generalizes as well as sNM3F when applied to new data. These findings suggest that the space-by-time decomposition of muscle activity finds robust task-discriminating modular representations of muscle activity and that the insertion of task discrimination objectives is useful for describing the task modulation of module recruitment. PMID:26217213

Task-discriminative space-by-time factorization of muscle activity.

PubMed

Delis, Ioannis; Panzeri, Stefano; Pozzo, Thierry; Berret, Bastien

2015-01-01

Movement generation has been hypothesized to rely on a modular organization of muscle activity. Crucial to this hypothesis is the ability to perform reliably a variety of motor tasks by recruiting a limited set of modules and combining them in a task-dependent manner. Thus far, existing algorithms that extract putative modules of muscle activations, such as Non-negative Matrix Factorization (NMF), identify modular decompositions that maximize the reconstruction of the recorded EMG data. Typically, the functional role of the decompositions, i.e., task accomplishment, is only assessed a posteriori. However, as motor actions are defined in task space, we suggest that motor modules should be computed in task space too. In this study, we propose a new module extraction algorithm, named DsNM3F, that uses task information during the module identification process. DsNM3F extends our previous space-by-time decomposition method (the so-called sNM3F algorithm, which could assess task performance only after having computed modules) to identify modules gauging between two complementary objectives: reconstruction of the original data and reliable discrimination of the performed tasks. We show that DsNM3F recovers the task dependence of module activations more accurately than sNM3F. We also apply it to electromyographic signals recorded during performance of a variety of arm pointing tasks and identify spatial and temporal modules of muscle activity that are highly consistent with previous studies. DsNM3F achieves perfect task categorization without significant loss in data approximation when task information is available and generalizes as well as sNM3F when applied to new data. These findings suggest that the space-by-time decomposition of muscle activity finds robust task-discriminating modular representations of muscle activity and that the insertion of task discrimination objectives is useful for describing the task modulation of module recruitment.

The Effect of Protein Mass Modulation on Human Dihydrofolate Reductase

PubMed Central

Francis, Kevin; Sapienza, Paul J.; Lee, Andrew L.; Kohen, Amnon

2016-01-01

Dihydrofolate reductase (DHFR) from Escherichia coli has long served as a model enzyme with which to elucidate possible links between protein dynamics and the catalyzed reaction. Such physical properties of its human counterpart have not been rigorously studied so far, but recent computer-based simulations suggest that these two DHFRs differ significantly in how closely coupled the protein dynamics and the catalyzed C-H→C hydride transfer step are. To test this prediction, two contemporary probes for studying the effect of protein dynamics on catalysis were combined here: temperature dependence of intrinsic kinetic isotope effects (KIEs) that are sensitive to the physical nature of the chemical step, and protein mass-modulation that slows down fast dynamics (femto- to picosecond timescale) throughout the protein. The intrinsic H/T KIEs of human DHFR, like those of E. coli DHFR, are shown to be temperature-independent in the range from 5–45 °C, indicating fast sampling of donor and acceptor distances (DADs) at the reaction’s transition state (or tunneling ready state – TRS). Mass modulation of these enzymes through isotopic labeling with 13C, 15N, and 2H at nonexchangeable hydrogens yield an 11% heavier enzyme. The additional mass has no effect on the intrinsic KIEs of the human enzyme. This finding indicates that the mass-modulation of the human DHFR affects neither DAD distribution nor the DAD’s conformational sampling dynamics. Furthermore, reduction in the enzymatic turnover number and the dissociation rate constant for the product indicate that the isotopic substitution affects kinetic steps that are not the catalyzed C-H→C hydride transfer. The findings are discussed in terms of fast dynamics and their role in catalysis, the comparison of calculations and experiments, and the interpretation of isotopically-modulated heavy enzymes in general. PMID:26813442

Error Rates and Channel Capacities in Multipulse PPM

NASA Technical Reports Server (NTRS)

Hamkins, Jon; Moision, Bruce

2007-01-01

A method of computing channel capacities and error rates in multipulse pulse-position modulation (multipulse PPM) has been developed. The method makes it possible, when designing an optical PPM communication system, to determine whether and under what conditions a given multipulse PPM scheme would be more or less advantageous, relative to other candidate modulation schemes. In conventional M-ary PPM, each symbol is transmitted in a time frame that is divided into M time slots (where M is an integer >1), defining an M-symbol alphabet. A symbol is represented by transmitting a pulse (representing 1) during one of the time slots and no pulse (representing 0 ) during the other M 1 time slots. Multipulse PPM is a generalization of PPM in which pulses are transmitted during two or more of the M time slots.

New classes of solutions in the coupled PT symmetric nonlocal nonlinear Schrödinger equations with four wave mixing

NASA Astrophysics Data System (ADS)

Vinayagam, P. S.; Radha, R.; Al Khawaja, U.; Ling, Liming

2018-06-01

We investigate generalized nonlocal coupled nonlinear Schorödinger equation containing Self-Phase Modulation, Cross-Phase Modulation and four wave mixing involving nonlocal interaction. By means of Darboux transformation we obtained a family of exact breathers and solitons including the Peregrine soliton, Kuznetsov-Ma breather, Akhmediev breather along with all kinds of soliton-soliton and breather-soltion interactions. We analyze and emphasize the impact of the four-wave mixing on the nature and interaction of the solutions. We found that the presence of four wave mixing converts a two-soliton solution into an Akhmediev breather. In particular, the inclusion of four wave mixing results in the generation of a new solutions which is spatially and temporally periodic called "Soliton (Breather) lattice".

Repetitive exposure: Brain and reflex measures of emotion and attention

PubMed Central

Ferrari, Vera; Bradley, Margaret M.; Codispoti, Maurizio; Lang, Peter J.

2010-01-01

Effects of massed repetition on the modulation of the late positive potential elicited during affective picture viewing were investigated in two experiments. Despite a difference in the number of repetitions across studies (from 5 to 30), results were quite similar: the late positive potential continued to be enhanced when viewing emotional, compared to neutral, pictures. On the other hand, massed repetition did prompt a reduction in the late positive potential that was most pronounced for emotional pictures. Startle probe P3 amplitude generally increased with repetition, suggesting diminished attention allocation to repeated pictures. The blink reflex, however, continued to be modulated by hedonic valence, despite massive massed repetition. Taken together, the data suggest that the amplitude of the late positive potential during picture viewing reflects both motivational significance and attention allocation. PMID:20701711

Astronaut Risk Levels During Crew Module (CM) Land Landing

NASA Technical Reports Server (NTRS)

Lawrence, Charles; Carney, Kelly S.; Littell, Justin

2007-01-01

The NASA Engineering Safety Center (NESC) is investigating the merits of water and land landings for the crew exploration vehicle (CEV). The merits of these two options are being studied in terms of cost and risk to the astronauts, vehicle, support personnel, and general public. The objective of the present work is to determine the astronaut dynamic response index (DRI), which measures injury risks. Risks are determined for a range of vertical and horizontal landing velocities. A structural model of the crew module (CM) is developed and computational simulations are performed using a transient dynamic simulation analysis code (LS-DYNA) to determine acceleration profiles. Landing acceleration profiles are input in a human factors model that determines astronaut risk levels. Details of the modeling approach, the resulting accelerations, and astronaut risk levels are provided.

JTRS/SCA and Custom/SDR Waveform Comparison

NASA Technical Reports Server (NTRS)

Oldham, Daniel R.; Scardelletti, Maximilian C.

2007-01-01

This paper compares two waveform implementations generating the same RF signal using the same SDR development system. Both waveforms implement a satellite modem using QPSK modulation at 1M BPS data rates with one half rate convolutional encoding. Both waveforms are partitioned the same across the general purpose processor (GPP) and the field programmable gate array (FPGA). Both waveforms implement the same equivalent set of radio functions on the GPP and FPGA. The GPP implements the majority of the radio functions and the FPGA implements the final digital RF modulator stage. One waveform is implemented directly on the SDR development system and the second waveform is implemented using the JTRS/SCA model. This paper contrasts the amount of resources to implement both waveforms and demonstrates the importance of waveform partitioning across the SDR development system.

Comparison of level discrimination, increment detection, and comodulation masking release in the audio- and envelope-frequency domains

PubMed Central

Nelson, Paul C.; Ewert, Stephan D.; Carney, Laurel H.; Dau, Torsten

2008-01-01

In general, the temporal structure of stimuli must be considered to account for certain observations made in detection and masking experiments in the audio-frequency domain. Two such phenomena are (1) a heightened sensitivity to amplitude increments with a temporal fringe compared to gated level discrimination performance and (2) lower tone-in-noise detection thresholds using a modulated masker compared to those using an unmodulated masker. In the current study, translations of these two experiments were carried out to test the hypothesis that analogous cues might be used in the envelope-frequency domain. Pure-tone carrier amplitude-modulation (AM) depth-discrimination thresholds were found to be similar using both traditional gated stimuli and using a temporally modulated fringe for a fixed standard depth (ms=0.25) and a range of AM frequencies (4-64 Hz). In a second experiment, masked sinusoidal AM detection thresholds were compared in conditions with and without slow and regular fluctuations imposed on the instantaneous masker AM depth. Release from masking was obtained only for very slow masker fluctuations (less than 2 Hz). A physiologically motivated model that effectively acts as a first-order envelope change detector accounted for several, but not all, of the key aspects of the data. PMID:17471731

Conformational Changes of an Interdomain Linker Mediate Mechanical Signal Transmission in Sensor Kinase BvgS

PubMed Central

Lesne, Elodie; Dupré, Elian; Locht, Camille

2017-01-01

ABSTRACT The whooping cough agent, Bordetella pertussis, controls the expression of its large virulence regulon in a coordinated manner through the two-component system BvgAS. BvgS is a dimeric, multidomain sensor kinase. Each monomer comprises, in succession, tandem periplasmic Venus flytrap (VFT) domains, a transmembrane segment, a cytoplasmic Per-Arnt-Sim (PAS) domain, a kinase module, and additional phosphorelay domains. BvgS shifts between kinase and phosphatase modes of activity in response to chemical modulators that modify the clamshell motions of the VFT domains. We have shown previously that this regulation involves a shift between distinct states of conformation and dynamics of the two-helix coiled-coil linker preceding the enzymatic module. In this work, we determined the mechanism of signal transduction across the membrane via a first linker, which connects the VFT and PAS domains of BvgS, using extensive cysteine cross-linking analyses and other approaches. Modulator perception by the periplasmic domains appears to trigger a small, symmetrical motion of the transmembrane segments toward the periplasm, causing rearrangements of the noncanonical cytoplasmic coiled coil that follows. As a consequence, the interface of the PAS domains is modified, which affects the second linker and eventually causes the shift of enzymatic activity. The major features of this first linker are well conserved among BvgS homologs, indicating that the mechanism of signal transduction unveiled here is likely to be generally relevant for this family of sensor kinases. IMPORTANCE Bordetella pertussis produces virulence factors coordinately regulated by the two-component system BvgAS. BvgS is a sensor kinase, and BvgA is a response regulator that activates gene transcription when phosphorylated by BvgS. Sensor kinases homologous to BvgS are also found in other pathogens. Our goal is to decipher the mechanisms of BvgS signaling, since these sensor kinases may represent new targets for antibacterial agents. Signal perception by the sensor domains of BvgS triggers small motions of the helical linker region underneath. The protein domain that follows this linker undergoes a large conformational change that amplifies the initial signal, causing a shift of activity from kinase to phosphatase. Because BvgS homologs harbor similar regions, these signaling mechanisms are likely to apply generally to that family of sensor kinases. PMID:28507245

Dive and Discover: New Arctic Educational Modules and Near Real-Time Coverage of Exploration on the Gakkel Ridge, Arctic Ocean

NASA Astrophysics Data System (ADS)

Humphris, S. E.; Conrad, D. S.; Joyce, K.; Whitcomb, L.; Carignan, C.

2006-12-01

The award-winning Dive and Discover web site will provide education and outreach activities during the International Polar Year for an expedition to investigate hydrothermal activity on the Gakkel Ridge using autonomous underwater vehicles. Created in 2000, this web site is targeted mainly at middle-school students (Grades 6-8) and the general public, but is structured to provide multiple layers and levels of information to cover a wide range of educational experience. The backbone of the site is a series of educational modules that address basic science concepts central to marine science and research being conducted in the deep ocean and on the seafloor. The site already contains considerable material on a range of topics pertinent to seafloor exploration, including mid-ocean ridges, hydrothermal vents, and vent biology, as well as Antarctica. For the cruise to the Gakkel Ridge, two new modules relevant to the upcoming Gakkel Ridge cruise are being developed: one on the geography, oceanography and ecosystems of the Arctic Ocean, and another on underwater robotics. During the 2007 cruise, Dive and Discover will provide daily updates on the progress of the cruise through still and video images from the ship and from the seafloor, graphical representations of a wide variety of oceanographic data, explanations about the technology being used, general information about life at sea on an ice breaker conducting marine research, and interviews with the scientists, engineers, and mariners that make oceanographic research possible. In addition, a "Mail Buoy" will allow the general public to communicate directly by email with scientists at sea. Once the cruise is completed, it will remain live on the site so that it can continue to be accessed and used by teachers during any part of the school year.

General Anesthetics Have Additive Actions on Three Ligand-Gated Ion Channels

PubMed Central

Jenkins, Andrew; Lobo, Ingrid A.; Gong, Diane; Trudell, James R.; Solt, Ken; Harris, R. Adron; Eger, Edmond I

2008-01-01

Background The purpose of this study was to determine whether pairs of compounds, including general anesthetics, could simultaneously modulate receptor function in a synergistic manner, thus demonstrating the existence of multiple intra-protein anesthetic binding sites. Methods Using standard electrophysiologic methods, we measured the effects of at least one combination of benzene, isoflurane, halothane, chloroform, flunitrazepam, zinc and pentobarbital on at least one of the following ligand gated ion channels: N-methyl-D-aspartate receptors (NMDARs), glycine receptors (GlyRs) and γ-aminobutyric acid type A receptors (GABAARs). Results All drug-drug-receptor combinations were found to exhibit additive, not synergistic modulation. Isoflurane with benzene additively depressed NMDAR function. Isoflurane with halothane additively enhanced GlyR function, as did isoflurane with zinc. Isoflurane with halothane additively enhanced GABAAR function as did all of the following: halothane with chloroform, pentobarbital with isoflurane, and flunitrazepam with isoflurane. Conclusions The simultaneous allosteric modulation of ligand gated ion channels by general anesthetics is entirely additive. Where pairs of general anesthetic drugs interact synergistically to produce general anesthesia, they must do so on systems more complex than a single receptor. PMID:18633027

Development of a simple, self-contained flight test data acquisition system

NASA Technical Reports Server (NTRS)

Renz, R. R. L.

1981-01-01

A low cost flight test data acquisition system, applicable to general aviation airplanes, was developed which meets criteria for doing longitudinal and lateral stability analysis. Th package consists of (1) a microprocessor controller and data acquisition module; (2) a transducer module; and (3) a power supply module. The system is easy to install and occupies space in the cabin or baggage compartment of the airplane. All transducers are contained in these modules except the total pressure tube, static pressure air temperature transducer, and control position transducers. The NASA-developed MMLE program was placed on a microcomputer on which all data reduction is done. The flight testing program undertaken proved both the flight testing hardware and the data reduction method to be applicable to the current field of general aviation airplanes.

Poisson traces, D-modules, and symplectic resolutions

NASA Astrophysics Data System (ADS)

Etingof, Pavel; Schedler, Travis

2018-03-01

We survey the theory of Poisson traces (or zeroth Poisson homology) developed by the authors in a series of recent papers. The goal is to understand this subtle invariant of (singular) Poisson varieties, conditions for it to be finite-dimensional, its relationship to the geometry and topology of symplectic resolutions, and its applications to quantizations. The main technique is the study of a canonical D-module on the variety. In the case the variety has finitely many symplectic leaves (such as for symplectic singularities and Hamiltonian reductions of symplectic vector spaces by reductive groups), the D-module is holonomic, and hence, the space of Poisson traces is finite-dimensional. As an application, there are finitely many irreducible finite-dimensional representations of every quantization of the variety. Conjecturally, the D-module is the pushforward of the canonical D-module under every symplectic resolution of singularities, which implies that the space of Poisson traces is dual to the top cohomology of the resolution. We explain many examples where the conjecture is proved, such as symmetric powers of du Val singularities and symplectic surfaces and Slodowy slices in the nilpotent cone of a semisimple Lie algebra. We compute the D-module in the case of surfaces with isolated singularities and show it is not always semisimple. We also explain generalizations to arbitrary Lie algebras of vector fields, connections to the Bernstein-Sato polynomial, relations to two-variable special polynomials such as Kostka polynomials and Tutte polynomials, and a conjectural relationship with deformations of symplectic resolutions. In the appendix we give a brief recollection of the theory of D-modules on singular varieties that we require.

Strain Modulations as a Mechanism to Reduce Stress Relaxation in Laryngeal Tissues

PubMed Central

Hunter, Eric J.; Siegmund, Thomas; Chan, Roger W.

2014-01-01

Vocal fold tissues in animal and human species undergo deformation processes at several types of loading rates: a slow strain involved in vocal fold posturing (on the order of 1 Hz or so), cyclic and faster posturing often found in speech tasks or vocal embellishment (1–10 Hz), and shear strain associated with vocal fold vibration during phonation (100 Hz and higher). Relevant to these deformation patterns are the viscous properties of laryngeal tissues, which exhibit non-linear stress relaxation and recovery. In the current study, a large strain time-dependent constitutive model of human vocal fold tissue is used to investigate effects of phonatory posturing cyclic strain in the range of 1 Hz to 10 Hz. Tissue data for two subjects are considered and used to contrast the potential effects of age. Results suggest that modulation frequency and extent (amplitude), as well as the amount of vocal fold overall strain, all affect the change in stress relaxation with modulation added. Generally, the vocal fold cover reduces the rate of relaxation while the opposite is true for the vocal ligament. Further, higher modulation frequencies appear to reduce the rate of relaxation, primarily affecting the ligament. The potential benefits of cyclic strain, often found in vibrato (around 5 Hz modulation) and intonational inflection, are discussed in terms of vocal effort and vocal pitch maintenance. Additionally, elderly tissue appears to not exhibit these benefits to modulation. The exacerbating effect such modulations may have on certain voice disorders, such as muscle tension dysphonia, are explored. PMID:24614616

Poisson traces, D-modules, and symplectic resolutions.

PubMed

Etingof, Pavel; Schedler, Travis

2018-01-01

We survey the theory of Poisson traces (or zeroth Poisson homology) developed by the authors in a series of recent papers. The goal is to understand this subtle invariant of (singular) Poisson varieties, conditions for it to be finite-dimensional, its relationship to the geometry and topology of symplectic resolutions, and its applications to quantizations. The main technique is the study of a canonical D-module on the variety. In the case the variety has finitely many symplectic leaves (such as for symplectic singularities and Hamiltonian reductions of symplectic vector spaces by reductive groups), the D-module is holonomic, and hence, the space of Poisson traces is finite-dimensional. As an application, there are finitely many irreducible finite-dimensional representations of every quantization of the variety. Conjecturally, the D-module is the pushforward of the canonical D-module under every symplectic resolution of singularities, which implies that the space of Poisson traces is dual to the top cohomology of the resolution. We explain many examples where the conjecture is proved, such as symmetric powers of du Val singularities and symplectic surfaces and Slodowy slices in the nilpotent cone of a semisimple Lie algebra. We compute the D-module in the case of surfaces with isolated singularities and show it is not always semisimple. We also explain generalizations to arbitrary Lie algebras of vector fields, connections to the Bernstein-Sato polynomial, relations to two-variable special polynomials such as Kostka polynomials and Tutte polynomials, and a conjectural relationship with deformations of symplectic resolutions. In the appendix we give a brief recollection of the theory of D-modules on singular varieties that we require.

Strain modulations as a mechanism to reduce stress relaxation in laryngeal tissues.

PubMed

Hunter, Eric J; Siegmund, Thomas; Chan, Roger W

2014-01-01

Vocal fold tissues in animal and human species undergo deformation processes at several types of loading rates: a slow strain involved in vocal fold posturing (on the order of 1 Hz or so), cyclic and faster posturing often found in speech tasks or vocal embellishment (1-10 Hz), and shear strain associated with vocal fold vibration during phonation (100 Hz and higher). Relevant to these deformation patterns are the viscous properties of laryngeal tissues, which exhibit non-linear stress relaxation and recovery. In the current study, a large strain time-dependent constitutive model of human vocal fold tissue is used to investigate effects of phonatory posturing cyclic strain in the range of 1 Hz to 10 Hz. Tissue data for two subjects are considered and used to contrast the potential effects of age. Results suggest that modulation frequency and extent (amplitude), as well as the amount of vocal fold overall strain, all affect the change in stress relaxation with modulation added. Generally, the vocal fold cover reduces the rate of relaxation while the opposite is true for the vocal ligament. Further, higher modulation frequencies appear to reduce the rate of relaxation, primarily affecting the ligament. The potential benefits of cyclic strain, often found in vibrato (around 5 Hz modulation) and intonational inflection, are discussed in terms of vocal effort and vocal pitch maintenance. Additionally, elderly tissue appears to not exhibit these benefits to modulation. The exacerbating effect such modulations may have on certain voice disorders, such as muscle tension dysphonia, are explored.

Integrated modular teaching in dermatology for undergraduate students: A novel approach

PubMed Central

Karthikeyan, Kaliaperumal; Kumar, Annapurna

2014-01-01

Context: Undergraduate teaching in dermatology comprises didactic lectures and clinical classes. Integrated modular teaching is a novel approach, which integrates basic sciences with dermatology in the form of a module. Further the module also incorporates various teaching modalities, which facilitate active participation from students and promotes learning. The pre- and post-test values showed the effectiveness of the integrated module. The students feedback was encouraging. Aims: The aim of this study was to determine the acceptance and opinion of undergraduate students regarding integrated modular teaching as a new teaching aid in dermatology. Settings and Design: This was a descriptive study. Varied teaching methodologies involving multiple disciplines were undertaken in six major undergraduate topics in dermatology for seventh and eighth semester students. Materials and Methods: A total of six modules were conducted over a period of 12 months for students of seventh and eighth semesters. The topics for the various modules were sexually transmitted diseases, acquired immunodeficiency syndrome, oral ulcers, leprosy, connective tissue disorders and psoriasis. Faculty members from different disciplines participated. Pre- and post-test were conducted before and after the modules respectively to gauge the effectiveness of the modules. Results: It was found that almost every student had a better score on the posttest as compared to the pretest. General feedback obtained from the students showed that all of them felt that modular teaching was a more interesting and useful teaching learning experience than conventional teaching. Conclusions: Integrated modular teaching can be an effective adjunct in imparting theoretical and practical knowledge to the students. Further, various teaching methodologies can be used in integrated modules effectively with active student participation. Thus integrated modular teaching addresses two important issues in medical education, namely integration and active student participation. PMID:25165641

Integrated modular teaching in dermatology for undergraduate students: A novel approach.

PubMed

Karthikeyan, Kaliaperumal; Kumar, Annapurna

2014-07-01

Undergraduate teaching in dermatology comprises didactic lectures and clinical classes. Integrated modular teaching is a novel approach, which integrates basic sciences with dermatology in the form of a module. Further the module also incorporates various teaching modalities, which facilitate active participation from students and promotes learning. The pre- and post-test values showed the effectiveness of the integrated module. The students feedback was encouraging. The aim of this study was to determine the acceptance and opinion of undergraduate students regarding integrated modular teaching as a new teaching aid in dermatology. This was a descriptive study. Varied teaching methodologies involving multiple disciplines were undertaken in six major undergraduate topics in dermatology for seventh and eighth semester students. A total of six modules were conducted over a period of 12 months for students of seventh and eighth semesters. The topics for the various modules were sexually transmitted diseases, acquired immunodeficiency syndrome, oral ulcers, leprosy, connective tissue disorders and psoriasis. Faculty members from different disciplines participated. Pre- and post-test were conducted before and after the modules respectively to gauge the effectiveness of the modules. It was found that almost every student had a better score on the posttest as compared to the pretest. General feedback obtained from the students showed that all of them felt that modular teaching was a more interesting and useful teaching learning experience than conventional teaching. Integrated modular teaching can be an effective adjunct in imparting theoretical and practical knowledge to the students. Further, various teaching methodologies can be used in integrated modules effectively with active student participation. Thus integrated modular teaching addresses two important issues in medical education, namely integration and active student participation.

Towards automatic musical instrument timbre recognition

NASA Astrophysics Data System (ADS)

Park, Tae Hong

This dissertation is comprised of two parts---focus on issues concerning research and development of an artificial system for automatic musical instrument timbre recognition and musical compositions. The technical part of the essay includes a detailed record of developed and implemented algorithms for feature extraction and pattern recognition. A review of existing literature introducing historical aspects surrounding timbre research, problems associated with a number of timbre definitions, and highlights of selected research activities that have had significant impact in this field are also included. The developed timbre recognition system follows a bottom-up, data-driven model that includes a pre-processing module, feature extraction module, and a RBF/EBF (Radial/Elliptical Basis Function) neural network-based pattern recognition module. 829 monophonic samples from 12 instruments have been chosen from the Peter Siedlaczek library (Best Service) and other samples from the Internet and personal collections. Significant emphasis has been put on feature extraction development and testing to achieve robust and consistent feature vectors that are eventually passed to the neural network module. In order to avoid a garbage-in-garbage-out (GIGO) trap and improve generality, extra care was taken in designing and testing the developed algorithms using various dynamics, different playing techniques, and a variety of pitches for each instrument with inclusion of attack and steady-state portions of a signal. Most of the research and development was conducted in Matlab. The compositional part of the essay includes brief introductions to "A d'Ess Are ," "Aboji," "48 13 N, 16 20 O," and "pH-SQ." A general outline pertaining to the ideas and concepts behind the architectural designs of the pieces including formal structures, time structures, orchestration methods, and pitch structures are also presented.

Study Modules for Calculus-Based General Physics. [Includes Modules 11-14: Collisions; Equilibrium of Rigid Bodies; Rotational Dynamics; and Fluid Mechanics].

ERIC Educational Resources Information Center

Fuller, Robert G., Ed.; And Others

This is part of a series of 42 Calculus Based Physics (CBP) modules totaling about 1,000 pages. The modules include study guides, practice tests, and mastery tests for a full-year individualized course in calculus-based physics based on the Personalized System of Instruction (PSI). The units are not intended to be used without outside materials;…

Study Modules for Calculus-Based General Physics. [Includes Modules 8-10: Conservation of Energy; Impulse and Momentum; and Rotational Motion].

ERIC Educational Resources Information Center

Fuller, Robert G., Ed.; And Others

This is part of a series of 42 Calculus Based Physics (CBP) modules totaling about 1,000 pages. The modules include study guides, practice tests, and mastery tests for a full-year individualized course in calculus-based physics based on the Personalized System of Instruction (PSI). The units are not intended to be used without outside materials;…

Power-law modulation of the scalar power spectrum from a heavy field with a monomial potential

NASA Astrophysics Data System (ADS)

Huang, Qing-Guo; Pi, Shi

2018-04-01

The effects of heavy fields modulate the scalar power spectrum during inflation. We analytically calculate the modulations of the scalar power spectrum from a heavy field with a separable monomial potential, i.e. V(phi)~ phin. In general the modulation is characterized by a power-law oscillation which is reduced to the logarithmic oscillation in the case of n=2.

Getting Down to Business: Fertilizer and Pesticide Service, Module 5. Teacher Guide. Entrepreneurship Training Components.

ERIC Educational Resources Information Center

McBain, Susan L.

This is the fifth in a set of 36 teacher guides for the Entrepreneurship Training modules and accompanies CE 031 038. Its purpose is to give students some idea of what it is like to own and operate a fertilizer and pesticide service. Following an overview are general notes on use of the module. Suggested steps for module use contain suggestions on…

Study Modules for Calculus-Based General Physics. [Includes Modules 3-5: Planar Motion; Newton's Laws; and Vector Multiplication].

ERIC Educational Resources Information Center

Fuller, Robert G., Ed.; And Others

This is part of a series of 42 Calculus Based Physics (CBP) modules totaling about 1,000 pages. The modules include study guides, practice tests, and mastery tests for a full-year individualized course in calculus-based physics based on the Personalized System of Instruction (PSI). The units are not intended to be used without outside materials;…

Study Modules for Calculus-Based General Physics. [Includes Modules 27-30: Direct-Current Circuits; Magnetic Forces; Ampere's Law; and Faraday's Law].

ERIC Educational Resources Information Center

Fuller, Robert G., Ed.; And Others

This is part of a series of 42 Calculus Based Physics (CBP) modules totaling about 1,000 pages. The modules indlude study guides, practice tests, and mastery tests for a full-year individualized course in calculus-based physics based on the Personalized System of Instruction (PSI). The units are not intended to be used without outside materials;…

Laguerre-Gaussian, Hermite-Gaussian, Bessel-Gaussian, and Finite-Energy Airy Beams Carrying Orbital Angular Momentum in Strongly Nonlocal Nonlinear Media

NASA Astrophysics Data System (ADS)

Wu, Zhenkun; Gu, Yuzong

2016-12-01

The propagation of two-dimensional beams is analytically and numerically investigated in strongly nonlocal nonlinear media (SNNM) based on the ABCD matrix. The two-dimensional beams reported in this paper are described by the product of the superposition of generalized Laguerre-Gaussian (LG), Hermite-Gaussian (HG), Bessel-Gaussian (BG), and circular Airy (CA) beams, carrying an orbital angular momentum (OAM). Owing to OAM and the modulation of SNNM, we find that the propagation of these two-dimensional beams exhibits complete rotation and periodic inversion: the spatial intensity profile first extends and then diminishes, and during the propagation the process repeats to form a breath-like phenomenon.

Antimicrobial and Virulence-Modulating Effects of Clove Essential Oil on the Foodborne Pathogen Campylobacter jejuni

PubMed Central

Kovács, Judit K.; Felső, Péter; Makszin, Lilla; Pápai, Zoltán; Horváth, Györgyi; Ábrahám, Hajnalka; Palkovics, Tamás; Böszörményi, Andrea; Emődy, Levente

2016-01-01

ABSTRACT Our study investigated the antimicrobial action of clove (Syzygium aromaticum) essential oil (EO) on the zoonotic pathogen Campylobacter jejuni. After confirming the clove essential oil's general antibacterial effect, we analyzed the reference strain Campylobacter jejuni NCTC 11168. Phenotypic, proteomic, and transcriptomic methods were used to reveal changes in cell morphology and functions when exposed to sublethal concentrations of clove EO. The normally curved cells showed markedly straightened and shrunken morphology on the scanning electron micrographs as a result of stress. Although, oxidative stress, as a generally accepted response to essential oils, was also present, the dominance of a general stress response was demonstrated by reverse transcription-PCR (RT-PCR). The results of RT-PCR and two-dimensional (2D) PAGE revealed that clove oil perturbs the expression of virulence-associated genes taking part in the synthesis of flagella, PEB1, PEB4, lipopolysaccharide (LPS), and serine protease. Loss of motility was also detected by a phenotypic test. Bioautographic analysis revealed that besides its major component, eugenol, at least four other spots of clove EO possessed bactericidal activity against C. jejuni. Our findings show that clove EO has a marked antibacterial and potential virulence-modulating effect on C. jejuni. IMPORTANCE This study demonstrates that the components of clove essential oil influence not only the expression of general stress genes but also the expression of virulence-associated genes. Based on this finding, alternative strategies can be worked on to control this important foodborne pathogen. PMID:27520816

Health Instruction Packages: Health Education for Consumers.

ERIC Educational Resources Information Center

Edgerly, Gisele; And Others

Text, illustrations and exercises are utilized in this set of six learning modules dealing with health topics of interest to the general public. The first module, "Do You Know Your Rights as a Patient?" by Gisele Edgerly, details the personal and financial rights of hospital patients. The second module, "The Consumer's Guide to…

AUTOMOTIVE DIESEL MAINTENANCE 2. UNIT IX, AUTOMATIC TRANSMISSIONS--HYDRAULIC SYSTEM (PART I).

ERIC Educational Resources Information Center

Human Engineering Inst., Cleveland, OH.

THIS MODULE OF A 25-MODULE COURSE IS DESIGNED TO DEVELOP AN UNDERSTANDING OF THE OIL FLOW WITHIN HYDRAULIC TRANSMISSIONS USED ON DIESEL POWERED VEHICLES. TOPICS ARE GENERAL DESCRIPTION, HYDRAULIC CIRCUITS, AND BRAKE HYDRAULIC CIRCUIT AND OPERATION. THE MODULE CONSISTS OF A SELF-INSTRUCTIONAL PROGRAMED TRAINING FILM "LEARNING ABOUT THE ALLISON…

Vocational-Technical Physics Project. Instructor's Manual. Field Test Edition.

ERIC Educational Resources Information Center

Forsyth Technical Inst., Winston-Salem, NC.

This instructor's manual in vocational physics consists of five modules: Jacks, Thermometers, The Alternator, The Pool Table, and The Radiator. It is an individualized approach, designed for use with accompanying student manuals on each of the individual modules. Each module in the instructor's manual consists of a general description plus an…

Advanced Chemistry for Operators. Training Module 1.321.3.77.

ERIC Educational Resources Information Center

Kirkwood Community Coll., Cedar Rapids, IA.

This document is an instructional module package prepared in objective form for use by an instructor familiar with inorganic and general organic chemistry as applied to water and wastewater treatment. Included are objectives, instructor guides, and student handouts. The module contains material related to chemical reactions in water solutions,…

Identity-Specific Reward Representations in Orbitofrontal Cortex Are Modulated by Selective Devaluation

PubMed Central

Howard, James D.

2017-01-01

Goal-directed behavior is sensitive to the current value of expected outcomes. This requires independent representations of specific rewards, which have been linked to orbitofrontal cortex (OFC) function. However, the mechanisms by which the human brain updates specific goals on the fly, and translates those updates into choices, have remained unknown. Here we implemented selective devaluation of appetizing food odors in combination with pattern-based neuroimaging and a decision-making task. We found that in a hungry state, participants chose to smell high-intensity versions of two value-matched food odor rewards. After eating a meal corresponding to one of the two odors, participants switched choices toward the low intensity of the sated odor but continued to choose the high intensity of the nonsated odor. This sensory-specific behavioral effect was mirrored by pattern-based changes in fMRI signal in lateral posterior OFC, where specific reward identity representations were altered after the meal for the sated food odor but retained for the nonsated counterpart. In addition, changes in functional connectivity between the OFC and general value coding in ventromedial prefrontal cortex (vmPFC) predicted individual differences in satiety-related choice behavior. These findings demonstrate how flexible representations of specific rewards in the OFC are updated by devaluation, and how functional connections to vmPFC reflect the current value of outcomes and guide goal-directed behavior. SIGNIFICANCE STATEMENT The orbitofrontal cortex (OFC) is critical for goal-directed behavior. A recent proposal is that OFC fulfills this function by representing a variety of state and task variables (“cognitive maps”), including a conjunction of expected reward identity and value. Here we tested how identity-specific representations of food odor reward are updated by satiety. We found that fMRI pattern-based signatures of reward identity in lateral posterior OFC were modulated after selective devaluation, and that connectivity between this region and general value coding ventromedial prefrontal cortex (vmPFC) predicted choice behavior. These results provide evidence for a mechanism by which devaluation modulates a cognitive map of expected reward in OFC and thereby alters general value signals in vmPFC to guide goal-directed behavior. PMID:28159906

ODIN system technology module library, 1972 - 1973

NASA Technical Reports Server (NTRS)

Hague, D. S.; Watson, D. A.; Glatt, C. R.; Jones, R. T.; Galipeau, J.; Phoa, Y. T.; White, R. J.

1978-01-01

ODIN/RLV is a digital computing system for the synthesis and optimization of reusable launch vehicle preliminary designs. The system consists of a library of technology modules in the form of independent computer programs and an executive program, ODINEX, which operates on the technology modules. The technology module library contains programs for estimating all major military flight vehicle system characteristics, for example, geometry, aerodynamics, economics, propulsion, inertia and volumetric properties, trajectories and missions, steady state aeroelasticity and flutter, and stability and control. A general system optimization module, a computer graphics module, and a program precompiler are available as user aids in the ODIN/RLV program technology module library.

Involvement of S-nitrosothiols modulation by S-nitrosoglutathione reductase in defence responses of lettuce and wild Lactuca spp. to biotrophic mildews.

PubMed

Tichá, Tereza; Sedlářová, Michaela; Činčalová, Lucie; Trojanová, Zuzana Drábková; Mieslerová, Barbora; Lebeda, Aleš; Luhová, Lenka; Petřivalský, Marek

2018-05-01

Resistant Lactuca spp. genotypes can efficiently modulate levels of S-nitrosothiols as reactive nitrogen species derived from nitric oxide in their defence mechanism against invading biotrophic pathogens including lettuce downy mildew. S-Nitrosylation belongs to principal signalling pathways of nitric oxide in plant development and stress responses. Protein S-nitrosylation is regulated by S-nitrosoglutathione reductase (GSNOR) as a key catabolic enzyme of S-nitrosoglutathione (GSNO), the major intracellular S-nitrosothiol. GSNOR expression, level and activity were studied in leaves of selected genotypes of lettuce (Lactuca sativa) and wild Lactuca spp. during interactions with biotrophic mildews, Bremia lactucae (lettuce downy mildew), Golovinomyces cichoracearum (lettuce powdery mildew) and non-pathogen Pseudoidium neolycopersici (tomato powdery mildew) during 168 h post inoculation (hpi). GSNOR expression was increased in all genotypes both in the early phase at 6 hpi and later phase at 72 hpi, with a high increase observed in L. sativa UCDM2 responses to all three pathogens. GSNOR protein also showed two-phase increase, with highest changes in L. virosa-B. lactucae and L. sativa cv. UCDM2-G. cichoracearum pathosystems, whereas P. neolycopersici induced GSNOR protein at 72 hpi in all genotypes. Similarly, a general pattern of modulated GSNOR activities in response to biotrophic mildews involves a two-phase increase at 6 and 72 hpi. Lettuce downy mildew infection caused GSNOR activity slightly increased only in resistant L. saligna and L. virosa genotypes; however, all genotypes showed increased GSNOR activity both at 6 and 72 hpi by lettuce powdery mildew. We observed GSNOR-mediated decrease of S-nitrosothiols as a general feature of Lactuca spp. response to mildew infection, which was also confirmed by immunohistochemical detection of GSNOR and GSNO in infected plant tissues. Our results demonstrate that GSNOR is differentially modulated in interactions of susceptible and resistant Lactuca spp. genotypes with fungal mildews and uncover the role of S-nitrosylation in molecular mechanisms of plant responses to biotrophic pathogens.

A comparative study of standard intensity-modulated radiotherapy and RapidArc planning techniques for ipsilateral and bilateral head and neck irradiation

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

Pursley, Jennifer, E-mail: jpursley@mgh.harvard.edu; Department of Radiation Oncology, Massachusetts General Hospital, Boston, MA; Damato, Antonio L.

The purpose of this study was to investigate class solutions using RapidArc volumetric-modulated arc therapy (VMAT) planning for ipsilateral and bilateral head and neck (H&N) irradiation, and to compare dosimetric results with intensity-modulated radiotherapy (IMRT) plans. A total of 14 patients who received ipsilateral and 10 patients who received bilateral head and neck irradiation were retrospectively replanned with several volumetric-modulated arc therapy techniques. For ipsilateral neck irradiation, the volumetric-modulated arc therapy techniques included two 360° arcs, two 360° arcs with avoidance sectors around the contralateral parotid, two 260° or 270° arcs, and two 210° arcs. For bilateral neck irradiation, themore » volumetric-modulated arc therapy techniques included two 360° arcs, two 360° arcs with avoidance sectors around the shoulders, and 3 arcs. All patients had a sliding-window-delivery intensity-modulated radiotherapy plan that was used as the benchmark for dosimetric comparison. For ipsilateral neck irradiation, a volumetric-modulated arc therapy technique using two 360° arcs with avoidance sectors around the contralateral parotid was dosimetrically comparable to intensity-modulated radiotherapy, with improved conformity (conformity index = 1.22 vs 1.36, p < 0.04) and lower contralateral parotid mean dose (5.6 vs 6.8 Gy, p < 0.03). For bilateral neck irradiation, 3-arc volumetric-modulated arc therapy techniques were dosimetrically comparable to intensity-modulated radiotherapy while also avoiding irradiation through the shoulders. All volumetric-modulated arc therapy techniques required fewer monitor units than sliding-window intensity-modulated radiotherapy to deliver treatment, with an average reduction of 35% for ipsilateral plans and 67% for bilateral plans. Thus, for ipsilateral head and neck irradiation a volumetric-modulated arc therapy technique using two 360° arcs with avoidance sectors around the contralateral parotid is recommended. For bilateral neck irradiation, 2- or 3-arc techniques are dosimetrically comparable to intensity-modulated radiotherapy, but more work is needed to determine the optimal approaches by disease site.« less

A comparative study of standard intensity-modulated radiotherapy and RapidArc planning techniques for ipsilateral and bilateral head and neck irradiation.

PubMed

Pursley, Jennifer; Damato, Antonio L; Czerminska, Maria A; Margalit, Danielle N; Sher, David J; Tishler, Roy B

2017-01-01

The purpose of this study was to investigate class solutions using RapidArc volumetric-modulated arc therapy (VMAT) planning for ipsilateral and bilateral head and neck (H&N) irradiation, and to compare dosimetric results with intensity-modulated radiotherapy (IMRT) plans. A total of 14 patients who received ipsilateral and 10 patients who received bilateral head and neck irradiation were retrospectively replanned with several volumetric-modulated arc therapy techniques. For ipsilateral neck irradiation, the volumetric-modulated arc therapy techniques included two 360° arcs, two 360° arcs with avoidance sectors around the contralateral parotid, two 260° or 270° arcs, and two 210° arcs. For bilateral neck irradiation, the volumetric-modulated arc therapy techniques included two 360° arcs, two 360° arcs with avoidance sectors around the shoulders, and 3 arcs. All patients had a sliding-window-delivery intensity-modulated radiotherapy plan that was used as the benchmark for dosimetric comparison. For ipsilateral neck irradiation, a volumetric-modulated arc therapy technique using two 360° arcs with avoidance sectors around the contralateral parotid was dosimetrically comparable to intensity-modulated radiotherapy, with improved conformity (conformity index = 1.22 vs 1.36, p < 0.04) and lower contralateral parotid mean dose (5.6 vs 6.8Gy, p < 0.03). For bilateral neck irradiation, 3-arc volumetric-modulated arc therapy techniques were dosimetrically comparable to intensity-modulated radiotherapy while also avoiding irradiation through the shoulders. All volumetric-modulated arc therapy techniques required fewer monitor units than sliding-window intensity-modulated radiotherapy to deliver treatment, with an average reduction of 35% for ipsilateral plans and 67% for bilateral plans. Thus, for ipsilateral head and neck irradiation a volumetric-modulated arc therapy technique using two 360° arcs with avoidance sectors around the contralateral parotid is recommended. For bilateral neck irradiation, 2- or 3-arc techniques are dosimetrically comparable to intensity-modulated radiotherapy, but more work is needed to determine the optimal approaches by disease site. Copyright © 2017 American Association of Medical Dosimetrists. Published by Elsevier Inc. All rights reserved.

General Conformity Training Modules: Appendix A Sample Emissions Calculations

EPA Pesticide Factsheets

Appendix A of the training modules gives example calculations for external and internal combustion sources, construction, fuel storage and transfer, on-road vehicles, aircraft operations, storage piles, and paved roads.

Frequency modulation entrains slow neural oscillations and optimizes human listening behavior

PubMed Central

Henry, Molly J.; Obleser, Jonas

2012-01-01

The human ability to continuously track dynamic environmental stimuli, in particular speech, is proposed to profit from “entrainment” of endogenous neural oscillations, which involves phase reorganization such that “optimal” phase comes into line with temporally expected critical events, resulting in improved processing. The current experiment goes beyond previous work in this domain by addressing two thus far unanswered questions. First, how general is neural entrainment to environmental rhythms: Can neural oscillations be entrained by temporal dynamics of ongoing rhythmic stimuli without abrupt onsets? Second, does neural entrainment optimize performance of the perceptual system: Does human auditory perception benefit from neural phase reorganization? In a human electroencephalography study, listeners detected short gaps distributed uniformly with respect to the phase angle of a 3-Hz frequency-modulated stimulus. Listeners’ ability to detect gaps in the frequency-modulated sound was not uniformly distributed in time, but clustered in certain preferred phases of the modulation. Moreover, the optimal stimulus phase was individually determined by the neural delta oscillation entrained by the stimulus. Finally, delta phase predicted behavior better than stimulus phase or the event-related potential after the gap. This study demonstrates behavioral benefits of phase realignment in response to frequency-modulated auditory stimuli, overall suggesting that frequency fluctuations in natural environmental input provide a pacing signal for endogenous neural oscillations, thereby influencing perceptual processing. PMID:23151506

Different Evolutionary Modifications as a Guide to Rewire Two-Component Systems

PubMed Central

Krueger, Beate; Friedrich, Torben; Förster, Frank; Bernhardt, Jörg; Gross, Roy; Dandekar, Thomas

2012-01-01

Two-component systems (TCS) are short signalling pathways generally occurring in prokaryotes. They frequently regulate prokaryotic stimulus responses and thus are also of interest for engineering in biotechnology and synthetic biology. The aim of this study is to better understand and describe rewiring of TCS while investigating different evolutionary scenarios. Based on large-scale screens of TCS in different organisms, this study gives detailed data, concrete alignments, and structure analysis on three general modification scenarios, where TCS were rewired for new responses and functions: (i) exchanges in the sequence within single TCS domains, (ii) exchange of whole TCS domains; (iii) addition of new components modulating TCS function. As a result, the replacement of stimulus and promotor cassettes to rewire TCS is well defined exploiting the alignments given here. The diverged TCS examples are non-trivial and the design is challenging. Designed connector proteins may also be useful to modify TCS in selected cases. PMID:22586357

Study Modules for Calculus-Based General Physics. [Includes Modules 18-20: Sound; Temperature, Heat, and Thermodynamics: First Law; and Kinetic Theory of Gases].

ERIC Educational Resources Information Center

Fuller, Robert G., Ed.; And Others

This is part of a series of 42 Calculus Based Physics (CBP) modules totaling about 1,000 pages. The modules include study guides, practice tests, and mastery tests for a full-year individualized course in calculus-based physics based on the Personalized System of Instruction (PSI). The units are not intended to be used without outside materials;…

Study Modules for Calculus-Based General Physics. [Includes Modules 31-34: Inductance; Wave Properties of Light; Interference; and Introduction to Quantum Physics].

ERIC Educational Resources Information Center

Fuller, Robert G., Ed.; And Others

This is Part of a series of 41 Calculus Based Physics (CBP) modules totaling about 1,000 Pages. The modules include study guides, practice tests, and mastery tests for a full-year individualized courses in calculus-based physics based on the Personalized System of Instruction (PSI). The units are not intended to be used without outside materials;…

Study Modules for Calculus-Based General Physics. [Includes Modules 1 and 2: Dimensions and Vector Addition; Rectilinear Motion; plus a Trigonometry and Calculus Review].

ERIC Educational Resources Information Center

Fuller, Robert G., Ed.; And Others

This is part of a series of 42 Calculus Based Physics (CBP) modules totaling about 1,000 pages. The modules include study guides, practice tests, and mastery tests for a full-year individualized course in calculus-based physics based on the Personalized System of Instruction (PSI). The units are not intended to be used without outside materials;…

The ESPAT tool: a general-purpose DSS shell for solving stochastic optimization problems in complex river-aquifer systems

NASA Astrophysics Data System (ADS)

Macian-Sorribes, Hector; Pulido-Velazquez, Manuel; Tilmant, Amaury

2015-04-01

Stochastic programming methods are better suited to deal with the inherent uncertainty of inflow time series in water resource management. However, one of the most important hurdles in their use in practical implementations is the lack of generalized Decision Support System (DSS) shells, usually based on a deterministic approach. The purpose of this contribution is to present a general-purpose DSS shell, named Explicit Stochastic Programming Advanced Tool (ESPAT), able to build and solve stochastic programming problems for most water resource systems. It implements a hydro-economic approach, optimizing the total system benefits as the sum of the benefits obtained by each user. It has been coded using GAMS, and implements a Microsoft Excel interface with a GAMS-Excel link that allows the user to introduce the required data and recover the results. Therefore, no GAMS skills are required to run the program. The tool is divided into four modules according to its capabilities: 1) the ESPATR module, which performs stochastic optimization procedures in surface water systems using a Stochastic Dual Dynamic Programming (SDDP) approach; 2) the ESPAT_RA module, which optimizes coupled surface-groundwater systems using a modified SDDP approach; 3) the ESPAT_SDP module, capable of performing stochastic optimization procedures in small-size surface systems using a standard SDP approach; and 4) the ESPAT_DET module, which implements a deterministic programming procedure using non-linear programming, able to solve deterministic optimization problems in complex surface-groundwater river basins. The case study of the Mijares river basin (Spain) is used to illustrate the method. It consists in two reservoirs in series, one aquifer and four agricultural demand sites currently managed using historical (XIV century) rights, which give priority to the most traditional irrigation district over the XX century agricultural developments. Its size makes it possible to use either the SDP or the SDDP methods. The independent use of surface and groundwater can be examined with and without the aquifer. The ESPAT_DET, ESPATR and ESPAT_SDP modules were executed for the surface system, while the ESPAT_RA and the ESPAT_DET modules were run for the surface-groundwater system. The surface system's results show a similar performance between the ESPAT_SDP and ESPATR modules, with outperform the one showed by the current policies besides being outperformed by the ESPAT_DET results, which have the advantage of the perfect foresight. The surface-groundwater system's results show a robust situation in which the differences between the module's results and the current policies are lower due the use of pumped groundwater in the XX century crops when surface water is scarce. The results are realistic, with the deterministic optimization outperforming the stochastic one, which at the same time outperforms the current policies; showing that the tool is able to stochastically optimize river-aquifer water resources systems. We are currently working in the application of these tools in the analysis of changes in systems' operation under global change conditions. ACKNOWLEDGEMENT: This study has been partially supported by the IMPADAPT project (CGL2013-48424-C2-1-R) with Spanish MINECO (Ministerio de Economía y Competitividad) funds.

Modeling of a multileaf collimator

NASA Astrophysics Data System (ADS)

Kim, Siyong

A comprehensive physics model of a multileaf collimator (MLC) field for treatment planning was developed. Specifically, an MLC user interface module that includes a geometric optimization tool and a general method of in- air output factor calculation were developed. An automatic tool for optimization of MLC conformation is needed to realize the potential benefits of MLC. It is also necessary that a radiation therapy treatment planning (RTTP) system is capable of modeling MLC completely. An MLC geometric optimization and user interface module was developed. The planning time has been reduced significantly by incorporating the MLC module into the main RTTP system, Radiation Oncology Computer System (ROCS). The dosimetric parameter that has the most profound effect on the accuracy of the dose delivered with an MLC is the change in the in-air output factor that occurs with field shaping. It has been reported that the conventional method of calculating an in-air output factor cannot be used for MLC shaped fields accurately. Therefore, it is necessary to develop algorithms that allow accurate calculation of the in-air output factor. A generalized solution for an in-air output factor calculation was developed. Three major contributors of scatter to the in-air output-flattening filter, wedge, and tertiary collimator-were considered separately. By virtue of a field mapping method, in which a source plane field determined by detector's eye view is mapped into a detector plane field, no additional dosimetric data acquisition other than the standard data set for a range of square fields is required for the calculation of head scatter. Comparisons of in-air output factors between calculated and measured values show a good agreement for both open and wedge fields. For rectangular fields, a simple equivalent square formula was derived based on the configuration of a linear accelerator treatment head. This method predicts in-air output to within 1% accuracy. A two-effective-source algorithm was developed to account for the effect of source to detector distance on in-air output for wedge fields. Two effective sources, one for head scatter and the other for wedge scatter, were dealt with independently. Calculations provided less than 1% difference of in-air output factors from measurements. This approach offers the best comprehensive accuracy in radiation delivery with field shapes defined using MLC. This generalized model works equally well with fields shaped by any type of tertiary collimator and have the necessary framework to extend its application to intensity modulated radiation therapy.

Health Occupations Module. The Skeletal System--II.

ERIC Educational Resources Information Center

Temple Univ., Philadelphia, PA. Div. of Vocational Education.

This module on the skeletal system is one of eight modules designed for individualized instruction in health occupations education programs at both the secondary and postsecondary levels. This module contains an introduction to the module topic, two objectives (e.g., list the types of joints and movements, and give examples), and two learning…

Interlocking Toy Building Blocks as Hands-On Learning Modules for Blind and Visually Impaired Chemistry Students

ERIC Educational Resources Information Center

Melaku, Samuel; Schreck, James O.; Griffin, Kameron; Dabke, Rajeev B.

2016-01-01

Interlocking toy building blocks (e.g., Lego) as chemistry learning modules for blind and visually impaired (BVI) students in high school and undergraduate introductory or general chemistry courses are presented. Building blocks were assembled on a baseplate to depict the relative changes in the periodic properties of elements. Modules depicting…

Insulin: All You Need To Know but Were Afraid To Ask. A Patient Education Module.

ERIC Educational Resources Information Center

McGrath, Zoe F.; Moseley, James L.

This learning module is intended to assist outpatient professional nurses in teaching patients to measure and administer their own insulin and to deal with diabetic emergencies when out of the hospital. The instructor's information (presented in an appendix) includes an overview of the topics covered in the patient module, general directions for…

Planning Educational Activities and Teaching Strategies on Constructing a Conservation Educational Module

ERIC Educational Resources Information Center

Dimopoulos, Dimitrios I.; Paraskevopoulos, Stefanos; Pantis, John D.

2009-01-01

This paper describes the design of an educational module which aims to raise awareness and change the attitudes of elementary school students about focal endangered species in protected areas. The proposed design builds on, and extends the General Teaching Model. The educational module which was developed through this approach was pilot-tested in…

Exploratory Development on an Electronic Safing and Arming Device for Ordnance Fuzing

DTIC Science & Technology

1983-02-01

to the bridges. Two units were subjected to MIL-STD-331, Test 101, Jolt. The EBMs were placed in the S & A cavity of an M739 fuze body for this test...of the program was to explore a concept for a safe, reliable, general purpose, low cost, electronic, A ’ zsafing and arming ( S & A ) system for use in...breadboard model hardware of the electronic S & A device. The electronic S & A devicu consists of an explosive barrier moduls (EBM) explosive train

The CCTC Quick-Reacting General War Gaming System (QUICK) Program Maintenance Manual. Volume I. Data Management Subsystem. Change 3.

DTIC Science & Technology

1980-05-22

cross -referenced with the number of the data transaction listed in the data module quality con- trol list NVB Integer variable used to...Organization of the Joint Chiefs of Staff. Technical support was provided by System Sciences, Incorporated under Contract Number DCA100-75-C-0019. Change set... Contract Number DCA 100-75-C-0019. Change set two was prepared u nder Contract Number DCA 100-78-C-0035. Computer Sciences Corporation prepared change

The Cauchy problem for the generalized Zakharov-Kuznetsov equation on modulation spaces

NASA Astrophysics Data System (ADS)

Kato, Tomoya

2018-03-01

We consider the Cauchy problem for the generalized Zakharov-Kuznetsov equation ∂t u +∂x1 Δu =∂x1 (u m + 1) on three and higher dimensions. We mainly study the local well-posedness and the small data global well-posedness in the modulation space M2,10 (Rn) for m ≥ 4 and n ≥ 3. We also investigate the quartic case, i.e., m = 3.

Investigating the Consistency of Models for Water Splitting Systems by Light and Voltage Modulated Techniques.

PubMed

Bertoluzzi, Luca; Bisquert, Juan

2017-01-05

The optimization of solar energy conversion devices relies on their accurate and nondestructive characterization. The small voltage perturbation techniques of impedance spectroscopy (IS) have proven to be very powerful to identify the main charge storage modes and charge transfer processes that control device operation. Here we establish the general connection between IS and light modulated techniques such as intensity modulated photocurrent (IMPS) and photovoltage spectroscopies (IMVS) for a general system that converts light to energy. We subsequently show how these techniques are related to the steady-state photocurrent and photovoltage and the external quantum efficiency. Finally, we express the IMPS and IMVS transfer functions in terms of the capacitive and resistive features of a general equivalent circuit of IS for the case of a photoanode used for solar fuel production. We critically discuss how much knowledge can be extracted from the combined use of those three techniques.

Effect of post-encoding emotion on recollection and familiarity for pictures.

PubMed

Wang, Bo; Ren, Yanju

2017-07-01

Although prior studies have examined the effect of post-encoding emotional arousal on recognition memory for words, it is unknown whether the enhancement effect observed on words generalizes to pictures. Furthermore, prior studies using words have showed that the effect of emotional arousal can be modulated by stimuli valence and delay in emotion induction, but it is unclear whether such modulation can extend to pictures and whether other factors such as encoding method (incidental vs. intentional encoding) can be modulatory. Five experiments were conducted to answer these questions. In Experiment 1, participants encoded a list of neutral and negative pictures and then watched a 3-min neutral or negative video. The delayed test showed that negative arousal impaired recollection regardless of picture valence but had no effect on familiarity. Experiment 2 replicated the above findings. Experiment 3 was similar to Experiment 1 except that participants watched a 3-min neutral, negative, or positive video and conducted free recall before the recognition test. Unlike the prior two experiments, the impairment effect of negative arousal disappeared. Experiment 4, where the free recall task was eliminated, replicated the results from Experiment 3. Experiment 5 replicated Experiments 1 and 2 and further showed that the impairment effects of negative arousal could be modulated by delay in emotion induction but not by encoding method or stimuli valence. Taken together, the current study suggests that the enhancement effect observed on words may not generalize to pictures.

Disaster easily averted? Data confidentiality and the hospital desktop computer.

PubMed

Sethi, Neeraj; Lane, Gethin; Newton, Sophie; Egan, Philip; Ghosh, Samit

2014-05-01

We specifically identified the hospital desktop computer as a potential source of breaches in confidentiality. We aimed to evaluate if there was accessible, unprotected, confidential information stored on the desktop screen on computers in a district general hospital and if so, how a teaching intervention could improve this situation. An unannounced spot check of 59 ward computers was performed. Data were collected regarding how many had confidential information stored on the desktop screen without any password protection. An online learning module was mandated for healthcare staff and a second cycle of inspection performed. A district general hospital. Two doctors conducted the audit. Computers in clinical areas were assessed. All clinical staff with computer access underwent the online learning module. An online learning module regarding data protection and confidentiality. In the first cycle, 55% of ward computers had easily accessible patient or staff confidential information stored on their desktop screen. This included handovers, referral letters, staff sick leave lists, audits and nursing reports. The majority (85%) of computers accessed were logged in under a generic username and password. The intervention produced an improvement in the second cycle findings with only 26% of computers being found to have unprotected confidential information stored on them. The failure to comply with appropriate confidential data protection regulations is a persistent problem. Education produces some improvement but we also propose a systemic approach to solving this problem. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Modular space station

NASA Technical Reports Server (NTRS)

1972-01-01

The modular space station comprising small, shuttle-launched modules, and characterized by low initial cost and incremental manning, is described. The initial space station is designed to be delivered into orbit by three space shuttles and assembled in space. The three sections are the power/subsystems module, the crew/operations module, and the general purpose laboratory module. It provides for a crew of six. Subsequently duplicate/crew/operations and power/subsystems modules will be mated to the original modules, and provide for an additional six crewmen. A total of 17 research and applications modules is planned, three of which will be free-flying modules. Details are given on the program plan, modular characteristics, logistics, experiment support capability and requirements, operations analysis, design support analyses, and shuttle interfaces.

Resource Conservation and Recovery Act Training Module about Treatment, Storage and Disposal Facilities

EPA Pesticide Factsheets

This training module describes:general requirements applicable to treatment, storage, and disposal facilitiesrequirements for waste analysis and personnel training purpose of a contingency plan and list the emergency notification procedures.

A Western blot-based investigation of the yeast secretory pathway designed for an intermediate-level undergraduate cell biology laboratory.

PubMed

Hood-Degrenier, Jennifer K

2008-01-01

The movement of newly synthesized proteins through the endomembrane system of eukaryotic cells, often referred to generally as the secretory pathway, is a topic covered in most intermediate-level undergraduate cell biology courses. An article previously published in this journal described a laboratory exercise in which yeast mutants defective in two distinct steps of protein secretion were differentiated using a genetic reporter designed specifically to identify defects in the first step of the pathway, the insertion of proteins into the endoplasmic reticulum (Vallen, 2002). We have developed two versions of a Western blotting assay that serves as a second way of distinguishing the two secretory mutants, which we pair with the genetic assay in a 3-wk laboratory module. A quiz administered before and after students participated in the lab activities revealed significant postlab gains in their understanding of the secretory pathway and experimental techniques used to study it. A second survey administered at the end of the lab module assessed student perceptions of the efficacy of the lab activities; the results of this survey indicated that the experiments were successful in meeting a set of educational goals defined by the instructor.

Enhanced TCAS 2/CDTI traffic Sensor digital simulation model and program description

NASA Technical Reports Server (NTRS)

Goka, T.

1984-01-01

Digital simulation models of enhanced TCAS 2/CDTI traffic sensors are developed, based on actual or projected operational and performance characteristics. Two enhanced Traffic (or Threat) Alert and Collision Avoidance Systems are considered. A digital simulation program is developed in FORTRAN. The program contains an executive with a semireal time batch processing capability. The simulation program can be interfaced with other modules with a minimum requirement. Both the traffic sensor and CAS logic modules are validated by means of extensive simulation runs. Selected validation cases are discussed in detail, and capabilities and limitations of the actual and simulated systems are noted. The TCAS systems are not specifically intended for Cockpit Display of Traffic Information (CDTI) applications. These systems are sufficiently general to allow implementation of CDTI functions within the real systems' constraints.

A General Water Resources Regulation Software System in China

NASA Astrophysics Data System (ADS)

LEI, X.

2017-12-01

To avoid iterative development of core modules in water resource normal regulation and emergency regulation and improve the capability of maintenance and optimization upgrading of regulation models and business logics, a general water resources regulation software framework was developed based on the collection and analysis of common demands for water resources regulation and emergency management. It can provide a customizable, secondary developed and extensible software framework for the three-level platform "MWR-Basin-Province". Meanwhile, this general software system can realize business collaboration and information sharing of water resources regulation schemes among the three-level platforms, so as to improve the decision-making ability of national water resources regulation. There are four main modules involved in the general software system: 1) A complete set of general water resources regulation modules allows secondary developer to custom-develop water resources regulation decision-making systems; 2) A complete set of model base and model computing software released in the form of Cloud services; 3) A complete set of tools to build the concept map and model system of basin water resources regulation, as well as a model management system to calibrate and configure model parameters; 4) A database which satisfies business functions and functional requirements of general water resources regulation software can finally provide technical support for building basin or regional water resources regulation models.

View of damaged Apollo 13 Service Module from the Lunar/Command Modules

NASA Image and Video Library

1970-04-17

This view of the damaged Apollo 13 Service Module (SM) was photographed from the Lunar Module/Command Module following SM jettisoning. As seen here, an entire panel on the SM was blown away by the apparent explosion of oxygen tank number two located in Sector 4 of the SM. Two of the three fuel cells are visible just forward (above) the heavily damaged area. Three fuel cells, two oxygen tanks, and two hydrogen tanks are locate in Sector 4. The damaged area is located above the S-band high gain antenna. Nearest the camera is the Service Propulsion System (SPS) engine and nozzle. The damage to the SM caused the Apollo 13 crewmen to use the Lunar Module (LM) as a "lifeboat". The LM was jettisoned just prior to Earth reentry by the Command Module.

Non-Markovian quantum feedback networks II: Controlled flows

NASA Astrophysics Data System (ADS)

Gough, John E.

2017-06-01

The concept of a controlled flow of a dynamical system, especially when the controlling process feeds information back about the system, is of central importance in control engineering. In this paper, we build on the ideas presented by Bouten and van Handel [Quantum Stochastics and Information: Statistics, Filtering and Control (World Scientific, 2008)] and develop a general theory of quantum feedback. We elucidate the relationship between the controlling processes, Z, and the measured processes, Y, and to this end we make a distinction between what we call the input picture and the output picture. We should note that the input-output relations for the noise fields have additional terms not present in the standard theory but that the relationship between the control processes and measured processes themselves is internally consistent—we do this for the two main cases of quadrature measurement and photon-counting measurement. The theory is general enough to include a modulating filter which post-processes the measurement readout Y before returning to the system. This opens up the prospect of applying very general engineering feedback control techniques to open quantum systems in a systematic manner, and we consider a number of specific modulating filter problems. Finally, we give a brief argument as to why most of the rules for making instantaneous feedback connections [J. Gough and M. R. James, Commun. Math. Phys. 287, 1109 (2009)] ought to apply for controlled dynamical networks as well.

Study Modules for Calculus-Based General Physics. [Includes Modules 21-23: Second Law and Entropy; Coulomb's Law and the Electric Field; and Flux and Gauss' Law].

ERIC Educational Resources Information Center

Fuller, Robert G., Ed.; And Others

This is part of a series of 42 Calculus Based Physics (CBP) modules totaling about 1,000 pages. The modules include study guides, practice tests, and mastery tests for a full-year individualized course in calculus-based physics based on the Personalized System of Instruction (PSI). The units are not intended to be used without outside materials;…

Module theoretic zero structures for system matrices

NASA Technical Reports Server (NTRS)

Wyman, Bostwick F.; Sain, Michael K.

1987-01-01

The coordinate-free module-theoretic treatment of transmission zeros for MIMO transfer functions developed by Wyman and Sain (1981) is generalized to include noncontrollable and nonobservable linear dynamical systems. Rational, finitely-generated-modular, and torsion-divisible interpretations of the Rosenbrock system matrix are presented; Gamma-zero and Omega-zero modules are defined and shown to contain the output-decoupling and input-decoupling zero modules, respectively, as submodules; and the cases of left and right invertible transfer functions are considered.

System and method for tuning adjusting the central frequency of a laser while maintaining frequency stabilization to an external reference

NASA Technical Reports Server (NTRS)

Livas, Jeffrey (Inventor); Thorpe, James I. (Inventor); Numata, Kenji (Inventor)

2011-01-01

A method and system for stabilizing a laser to a frequency reference with an adjustable offset. The method locks a sideband signal generated by passing an incoming laser beam through the phase modulator to a frequency reference, and adjusts a carrier frequency relative to the locked sideband signal by changing a phase modulation frequency input to the phase modulator. The sideband signal can be a single sideband (SSB), dual sideband (DSB), or an electronic sideband (ESB) signal. Two separate electro-optic modulators can produce the DSB signal. The two electro-optic modulators can be a broadband modulator and a resonant modulator. With a DSB signal, the method can introduce two sinusoidal phase modulations at the phase modulator. With ESB signals, the method can further drive the optical phase modulator with an electrical signal with nominal frequency OMEGA(sub 1) that is phase modulated at a frequency OMEGA(sub 2)

Generalization of Fear to Respiratory Sensations.

PubMed

Schroijen, Mathias; Pappens, Meike; Schruers, Koen; Van den Bergh, Omer; Vervliet, Bram; Van Diest, Ilse

2015-09-01

Interoceptive fear conditioning (IFC), fear generalization and a lack of safety learning have all been hypothesized to play a role in the pathogenesis of panic disorder, but have never been examined in a single paradigm. The present study aims to investigate whether healthy participants (N=43) can learn both fear and safety to an interoceptive sensation, and whether such learning generalizes to other, similar sensations. Two intensities of inspiratory breathing impairment (induced by two pressure threshold loads of 6 and 25 cm H2O) served as interoceptive conditional stimuli (CSs) in a differential conditioning paradigm. An inspiratory occlusion was used as the unconditioned stimulus (US). Generalization was tested 24h after conditioning, using four generalization stimuli with intensities in-between CS+ and CS- (GSs: 8-10.5-14-18.5 cm H2O). Measures included US-expectancy, startle blink EMG responses, electrodermal activity and respiration. Perceptual discrimination of interoceptive CSs and GSs was explored with a discrimination task prior to acquisition and after generalization. Results indicate that differential fear learning was established for US-expectancy ratings. The group with a low intensity CS+ and a high intensity CS- showed the typical pattern of differential fear responding and a similarity-based generalization gradient. In contrast, the high intensity CS+ and low intensity CS- group showed impaired differential learning and complete generalization of fear. Our findings suggest that interoceptive fear learning and generalization are modulated by stimulus intensity and that the occurrence of discriminatory learning is closely related to fear generalization. Copyright © 2015. Published by Elsevier Ltd.

GVIPS Models and Software

NASA Technical Reports Server (NTRS)

Arnold, Steven M.; Gendy, Atef; Saleeb, Atef F.; Mark, John; Wilt, Thomas E.

2007-01-01

Two reports discuss, respectively, (1) the generalized viscoplasticity with potential structure (GVIPS) class of mathematical models and (2) the Constitutive Material Parameter Estimator (COMPARE) computer program. GVIPS models are constructed within a thermodynamics- and potential-based theoretical framework, wherein one uses internal state variables and derives constitutive equations for both the reversible (elastic) and the irreversible (viscoplastic) behaviors of materials. Because of the underlying potential structure, GVIPS models not only capture a variety of material behaviors but also are very computationally efficient. COMPARE comprises (1) an analysis core and (2) a C++-language subprogram that implements a Windows-based graphical user interface (GUI) for controlling the core. The GUI relieves the user of the sometimes tedious task of preparing data for the analysis core, freeing the user to concentrate on the task of fitting experimental data and ultimately obtaining a set of material parameters. The analysis core consists of three modules: one for GVIPS material models, an analysis module containing a specialized finite-element solution algorithm, and an optimization module. COMPARE solves the problem of finding GVIPS material parameters in the manner of a design-optimization problem in which the parameters are the design variables.

Evaluation of the microclimate in poultry transport module drawers during the marketing process of end-of-lay hens from farm to slaughter.

PubMed

Richards, G J; Wilkins, L J; Weeks, C A; Knowles, T G; Brown, S N

2012-11-10

Changes in module drawer temperature and relative humidity were monitored for 24 commercial loads of hens. Mathematical models revealed significant differences in predicted drawer temperature depending on their location and the outside environmental temperature. Higher predicted temperatures were found in uppermost drawers of the top modules at the front of the lorry, and lower temperatures in drawers on the outer sides of modules and in those drawers in modules next to the back of the lorry in both the upper and lower modules during transport. In the lairage, drawer temperature generally decreased, except in drawers at the top of modules where temperatures increased. Temperature increases were most often recorded in modules which had been located at the rear of the lorry, which were generally cooler during transport. End-of-lay hens would appear to be exposed to a greater risk of cold stress rather than heat stress in the UK. Inspection of birds during transport, or upon arrival, should be directed to the bottom and side drawers of a load when looking for cold stress, and the top row of drawers (centre) of the top modules when looking for heat stress. The frequency of inspections should increase at times of high ambient temperature while the birds are being held in lairages. Adjusting the numbers of birds loaded per drawer according to bird condition and weather appears to be an effective mitigation strategy which is already in use commercially.

An iterative network partition algorithm for accurate identification of dense network modules

PubMed Central

Sun, Siqi; Dong, Xinran; Fu, Yao; Tian, Weidong

2012-01-01

A key step in network analysis is to partition a complex network into dense modules. Currently, modularity is one of the most popular benefit functions used to partition network modules. However, recent studies suggested that it has an inherent limitation in detecting dense network modules. In this study, we observed that despite the limitation, modularity has the advantage of preserving the primary network structure of the undetected modules. Thus, we have developed a simple iterative Network Partition (iNP) algorithm to partition a network. The iNP algorithm provides a general framework in which any modularity-based algorithm can be implemented in the network partition step. Here, we tested iNP with three modularity-based algorithms: multi-step greedy (MSG), spectral clustering and Qcut. Compared with the original three methods, iNP achieved a significant improvement in the quality of network partition in a benchmark study with simulated networks, identified more modules with significantly better enrichment of functionally related genes in both yeast protein complex network and breast cancer gene co-expression network, and discovered more cancer-specific modules in the cancer gene co-expression network. As such, iNP should have a broad application as a general method to assist in the analysis of biological networks. PMID:22121225

Analysis of twelve-month degradation in three polycrystalline photovoltaic modules

NASA Astrophysics Data System (ADS)

Lai, T.; Potter, B. G.; Simmons-Potter, K.

2016-09-01

Polycrystalline silicon photovoltaic (PV) modules have the advantage of lower manufacturing cost as compared to their monocrystalline counterparts, but generally exhibit both lower initial module efficiencies and more significant early-stage efficiency degradation than do similar monocrystalline PV modules. For both technologies, noticeable deterioration in power conversion efficiency typically occurs over the first two years of usage. Estimating PV lifetime by examining the performance degradation behavior under given environmental conditions is, therefore, one of continual goals for experimental research and economic analysis. In the present work, accelerated lifecycle testing (ALT) on three polycrystalline PV technologies was performed in a full-scale, industrial-standard environmental chamber equipped with single-sun irradiance capability, providing an illumination uniformity of 98% over a 2 x 1.6m area. In order to investigate environmental aging effects, timedependent PV performance (I-V characteristic) was evaluated over a recurring, compressed day-night cycle, which simulated local daily solar insolation for the southwestern United States, followed by dark (night) periods. During a total test time of just under 4 months that corresponded to a year equivalent exposure on a fielded module, the temperature and humidity varied in ranges from 3°C to 40°C and 5% to 85% based on annual weather profiles for Tucson, AZ. Removing the temperature de-rating effect that was clearly seen in the data enabled the computation of normalized efficiency degradation with time and environmental exposure. Results confirm the impact of environmental conditions on the module long-term performance. Overall, more than 2% efficiency degradation in the first year of usage was observed for all thee polycrystalline Si solar modules. The average 5-year degradation of each PV technology was estimated based on their determined degradation rates.

GLUT4 Retention in Adipocytes Requires Two Intracellular Insulin-regulated Transport Steps

PubMed Central

Zeigerer, Anja; Lampson, Michael A.; Karylowski, Ola; Sabatini, David D.; Adesnik, Milton; Ren, Mindong; McGraw, Timothy E.

2002-01-01

Insulin regulates glucose uptake into fat and muscle by modulating the distribution of the GLUT4 glucose transporter between the surface and interior of cells. The GLUT4 trafficking pathway overlaps with the general endocytic recycling pathway, but the degree and functional significance of the overlap are not known. In this study of intact adipocytes, we demonstrate, by using a compartment-specific fluorescence-quenching assay, that GLUT4 is equally distributed between two intracellular pools: the transferrin receptor-containing endosomes and a specialized compartment that excludes the transferrin receptor. These pools of GLUT4 are in dynamic communication with one another and with the cell surface. Insulin-induced redistribution of GLUT4 to the surface requires mobilization of both pools. These data establish a role for the general endosomal system in the specialized, insulin-regulated trafficking of GLUT4. Trafficking through the general endosomal system is regulated by rab11. Herein, we show that rab11 is required for the transport of GLUT4 from endosomes to the specialized compartment and for the insulin-induced translocation to the cell surface, emphasizing the importance of the general endosomal pathway in the specialized trafficking of GLUT4. Based on these findings we propose a two-step model for GLUT4 trafficking in which the general endosomal recycling compartment plays a specialized role in the insulin-regulated traffic of GLUT4. This compartment-based model provides the framework for understanding insulin-regulated trafficking at a molecular level. PMID:12134080

GLUT4 retention in adipocytes requires two intracellular insulin-regulated transport steps.

PubMed

Zeigerer, Anja; Lampson, Michael A; Karylowski, Ola; Sabatini, David D; Adesnik, Milton; Ren, Mindong; McGraw, Timothy E

2002-07-01

Insulin regulates glucose uptake into fat and muscle by modulating the distribution of the GLUT4 glucose transporter between the surface and interior of cells. The GLUT4 trafficking pathway overlaps with the general endocytic recycling pathway, but the degree and functional significance of the overlap are not known. In this study of intact adipocytes, we demonstrate, by using a compartment-specific fluorescence-quenching assay, that GLUT4 is equally distributed between two intracellular pools: the transferrin receptor-containing endosomes and a specialized compartment that excludes the transferrin receptor. These pools of GLUT4 are in dynamic communication with one another and with the cell surface. Insulin-induced redistribution of GLUT4 to the surface requires mobilization of both pools. These data establish a role for the general endosomal system in the specialized, insulin-regulated trafficking of GLUT4. Trafficking through the general endosomal system is regulated by rab11. Herein, we show that rab11 is required for the transport of GLUT4 from endosomes to the specialized compartment and for the insulin-induced translocation to the cell surface, emphasizing the importance of the general endosomal pathway in the specialized trafficking of GLUT4. Based on these findings we propose a two-step model for GLUT4 trafficking in which the general endosomal recycling compartment plays a specialized role in the insulin-regulated traffic of GLUT4. This compartment-based model provides the framework for understanding insulin-regulated trafficking at a molecular level.

A molecular-sized optical logic circuit for digital modulation of a fluorescence signal

NASA Astrophysics Data System (ADS)

Nishimura, Takahiro; Tsuchida, Karin; Ogura, Yusuke; Tanida, Jun

2018-03-01

Fluorescence measurement allows simultaneous detection of multiple molecular species by using spectrally distinct fluorescence probes. However, due to the broad spectra of fluorescence emission, the multiplicity of fluorescence measurement is generally limited. To overcome this limitation, we propose a method to digitally modulate fluorescence output signals with a molecular-sized optical logic circuit by using optical control of fluorescence resonance energy transfer (FRET). The circuit receives a set of optical inputs represented with different light wavelengths, and then it switches high and low fluorescence intensity from a reporting molecule according to the result of the logic operation. By using combinational optical inputs in readout of fluorescence signals, the number of biomolecular species that can be identified is increased. To implement the FRET-based circuits, we designed two types of basic elements, YES and NOT switches. An YES switch produces a high-level output intensity when receiving a designated light wavelength input and a low-level intensity without the light irradiation. A NOT switch operates inversely to the YES switch. In experiments, we investigated the operation of the YES and NOT switches that receive a 532-nm light input and modulate the fluorescence intensity of Alexa Fluor 488. The experimental result demonstrates that the switches can modulate fluorescence signals according to the optical input.

Human Detection from a Mobile Robot Using Fusion of Laser and Vision Information

PubMed Central

Fotiadis, Efstathios P.; Garzón, Mario; Barrientos, Antonio

2013-01-01

This paper presents a human detection system that can be employed on board a mobile platform for use in autonomous surveillance of large outdoor infrastructures. The prediction is based on the fusion of two detection modules, one for the laser and another for the vision data. In the laser module, a novel feature set that better encapsulates variations due to noise, distance and human pose is proposed. This enhances the generalization of the system, while at the same time, increasing the outdoor performance in comparison with current methods. The vision module uses the combination of the histogram of oriented gradients descriptor and the linear support vector machine classifier. Current approaches use a fixed-size projection to define regions of interest on the image data using the range information from the laser range finder. When applied to small size unmanned ground vehicles, these techniques suffer from misalignment, due to platform vibrations and terrain irregularities. This is effectively addressed in this work by using a novel adaptive projection technique, which is based on a probabilistic formulation of the classifier performance. Finally, a probability calibration step is introduced in order to optimally fuse the information from both modules. Experiments in real world environments demonstrate the robustness of the proposed method. PMID:24008280

Human detection from a mobile robot using fusion of laser and vision information.

PubMed

Fotiadis, Efstathios P; Garzón, Mario; Barrientos, Antonio

2013-09-04

This paper presents a human detection system that can be employed on board a mobile platform for use in autonomous surveillance of large outdoor infrastructures. The prediction is based on the fusion of two detection modules, one for the laser and another for the vision data. In the laser module, a novel feature set that better encapsulates variations due to noise, distance and human pose is proposed. This enhances the generalization of the system, while at the same time, increasing the outdoor performance in comparison with current methods. The vision module uses the combination of the histogram of oriented gradients descriptor and the linear support vector machine classifier. Current approaches use a fixed-size projection to define regions of interest on the image data using the range information from the laser range finder. When applied to small size unmanned ground vehicles, these techniques suffer from misalignment, due to platform vibrations and terrain irregularities. This is effectively addressed in this work by using a novel adaptive projection technique, which is based on a probabilistic formulation of the classifier performance. Finally, a probability calibration step is introduced in order to optimally fuse the information from both modules. Experiments in real world environments demonstrate the robustness of the proposed method.

Emerging photovoltaic module technologies at PVUSA: A five-year assessment

NASA Astrophysics Data System (ADS)

Townsend, Tim

1995-04-01

The Photovoltaics for Utility Scale Applications (PVUSA) project tests two types of photovoltaic systems: new modules fielded as 20-kW emerging module technology (EMT) arrays, and more mature technologies fielded as 20- to 500-kW turnkey utility scale (US) systems. This report summarizes experiences of the PVUSA project in operating the first six 20-kW EMT photovoltaic systems. Five systems are installed at Davis, California, and one at Kihei, Hawaii. Products selected for testing and demonstration were judged to have potential for significant technical advancement or reduction in manufacturing cost. Features leading to selection of each system and findings over the average 5 years of operation are compared in the report. Factory product qualification test experiences along with field acceptance test results are documented. Evaluation includes a broad range of performance parameters, including long-term efficiency, seasonal generation patterns, and maintenance. While some of the arrays have operated as well as any commercial system, others have fared poorly. Throughout the procurement and operation of these precommercial PV modules, PVUSA has provided feedback to vendors, critical for product improvement. The data and evaluations in this report will be of further benefit to manufacturers and provide general comparative information on a variety of technologies to researchers in utilities, government, and industry alike.

CEF1/CDC5 alleles modulate transitions between catalytic conformations of the spliceosome

PubMed Central

Query, Charles C.; Konarska, Maria M.

2012-01-01

Conformational change within the spliceosome is required between the first and second catalytic steps of pre-mRNA splicing. A prior genetic screen for suppressors of an intron mutant that stalls between the two steps yielded both prp8 and non-prp8 alleles that suppressed second-step splicing defects. We have now identified the strongest non-prp8 suppressors as alleles of the NTC (Prp19 complex) component, CEF1. These cef1 alleles generally suppress second-step defects caused by a variety of intron mutations, mutations in U6 snRNA, or deletion of the second-step protein factor Prp17, and they can activate alternative 3′ splice sites. Genetic and functional interactions between cef1 and prp8 alleles suggest that they modulate the same event(s) in the first-to-second-step transition, most likely by stabilization of the second-step spliceosome; in contrast, alleles of U6 snRNA that also alter this transition modulate a distinct event, most likely by stabilization of the first-step spliceosome. These results implicate a myb-like domain of Cef1/CDC5 in interactions that modulate conformational states of the spliceosome and suggest that alteration of these events affects splice site use, resulting in alternative splicing-like patterns in yeast. PMID:22408182

Online dimensionality reduction using competitive learning and Radial Basis Function network.

PubMed

Tomenko, Vladimir

2011-06-01

The general purpose dimensionality reduction method should preserve data interrelations at all scales. Additional desired features include online projection of new data, processing nonlinearly embedded manifolds and large amounts of data. The proposed method, called RBF-NDR, combines these features. RBF-NDR is comprised of two modules. The first module learns manifolds by utilizing modified topology representing networks and geodesic distance in data space and approximates sampled or streaming data with a finite set of reference patterns, thus achieving scalability. Using input from the first module, the dimensionality reduction module constructs mappings between observation and target spaces. Introduction of specific loss function and synthesis of the training algorithm for Radial Basis Function network results in global preservation of data structures and online processing of new patterns. The RBF-NDR was applied for feature extraction and visualization and compared with Principal Component Analysis (PCA), neural network for Sammon's projection (SAMANN) and Isomap. With respect to feature extraction, the method outperformed PCA and yielded increased performance of the model describing wastewater treatment process. As for visualization, RBF-NDR produced superior results compared to PCA and SAMANN and matched Isomap. For the Topic Detection and Tracking corpus, the method successfully separated semantically different topics. Copyright © 2011 Elsevier Ltd. All rights reserved.

The role of selective estrogen receptor modulators in the treatment of schizophrenia.

PubMed

Bratek, Agnieszka; Krysta, Krzysztof; Drzyzga, Karolina; Barańska, Justyna; Kucia, Krzysztof

2016-09-01

Gender differences in schizophrenia have been recognized for a long time and it has been widely accepted that sex steroid hormones, especially estradiol, are strongly attributed to this fact. Two hypotheses regarding estradiol action in psychoses gained special research attention - the estrogen protection hypothesis and hypoestrogenism hypothesis. A growing number of studies have shown benefits in augmenting antipsychotic treatment with estrogens or selective estrogen receptor modulators (SERM). This review is focused on the role of selective estrogen receptor modulators in the treatment of schizophrenic patients. In order to achieve this result PubMed was searched using the following terms: schizophrenia, raloxifene, humans. We reviewed only randomized, placebo-controlled studies. Raloxifene, a selective estrogen receptor modulator was identified as useful to improve negative, positive, and general psychopathological symptoms, and also cognitive functions. All reviewed studies indicated improvement in at least one studied domain. Augmentation with raloxifene was found to be a beneficial treatment strategy for chronic schizophrenia both in female and male patients, however potential side effects (a small increase in the risk of venous thromboembolism and endometrial cancer) should be carefully considered. SERMs could be an effective augmentation strategy in the treatment of both men women with schizophrenia, although further research efforts are needed to study potential long-term side effects.

Fungi on the Skin: Dermatophytes and Malassezia

PubMed Central

White, Theodore C.; Findley, Keisha; Dawson, Thomas L.; Scheynius, Annika; Boekhout, Teun; Cuomo, Christina A.; Xu, Jun; Saunders, Charles W.

2014-01-01

Several human skin diseases and disorders are associated with two groups of fungi, the dermatophytes and Malassezia. Although these skin-related problems are not generally life threatening, they are among the most common diseases and disorders of mankind. These fungi are phylogenetically divergent, with the dermatophytes within the Ascomycota and Malassezia within Basidiomycota. Genome analysis indicates that the adaptations to the skin environment are different in these two groups of fungi. Malassezia are dependent on host lipids and secrete lipases and phospholipases that likely release host fatty acids. The dermatophytes encode multiple enzymes with potential roles in modulating host interactions: polyketide synthases, nonribosomal peptide synthetases, LysM, proteases, kinases, and pseudokinases. These two fungal groups have maximized their interactions with the host using two very different mechanisms. PMID:25085959

47 CFR 2.201 - Emission, modulation, and transmission characteristics.

Code of Federal Regulations, 2011 CFR

2011-10-01

..., and transmission characteristics. The following system of designating emission, modulation, and transmission characteristics shall be employed. (a) Emissions are designated according to their classification... characteristics. 2.201 Section 2.201 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL FREQUENCY...

47 CFR 2.201 - Emission, modulation, and transmission characteristics.

Code of Federal Regulations, 2010 CFR

2010-10-01

..., and transmission characteristics. The following system of designating emission, modulation, and transmission characteristics shall be employed. (a) Emissions are designated according to their classification... characteristics. 2.201 Section 2.201 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL FREQUENCY...

Seeking structural specificity: direct modulation of pentameric ligand-gated ion channels by alcohols and general anesthetics.

PubMed

Howard, Rebecca J; Trudell, James R; Harris, R Adron

2014-01-01

Alcohols and other anesthetic agents dramatically alter neurologic function in a wide range of organisms, yet their molecular sites of action remain poorly characterized. Pentameric ligand-gated ion channels, long implicated in important direct effects of alcohol and anesthetic binding, have recently been illuminated in renewed detail thanks to the determination of atomic-resolution structures of several family members from lower organisms. These structures provide valuable models for understanding and developing anesthetic agents and for allosteric modulation in general. This review surveys progress in this field from function to structure and back again, outlining early evidence for relevant modulation of pentameric ligand-gated ion channels and the development of early structural models for ion channel function and modulation. We highlight insights and challenges provided by recent crystal structures and resulting simulations, as well as opportunities for translation of these newly detailed models back to behavior and therapy.

Dairy propionibacteria as probiotics: recent evidences.

PubMed

Altieri, Clelia

2016-10-01

Nowdays there is evidence that dairy propionibacteria display probiotic properties, which as yet have been underestimated. The aim of this paper is to review the recent highlights of data representing the probiotic potential of dairy propionibacteria, studied both by general selection criteria (useful for all probiotic potentials), and by more specific and innovative approach. Dairy propionibacteria show a robust nature, that makes them able to overcome technological hurdles, allowing their future use in various fermented probiotic foods. In addition to the general selection criteria for probiotics in areas such as food safety, technological and digestive stress tolerance, many potential health benefits have been recently described for dairy propionibacteria, including, production of several active molecules and adhesion capability, that can mean a steady action in modulation of microbiota and of metabolic activity in the gut; their impact on intestinal inflammation, modulation of the immune system, potential modulation of risk factors for cancer development modulation of intestinal absorption.

Seeking Structural Specificity: Direct Modulation of Pentameric Ligand-Gated Ion Channels by Alcohols and General Anesthetics

PubMed Central

Trudell, James R.; Harris, R. Adron

2014-01-01

Alcohols and other anesthetic agents dramatically alter neurologic function in a wide range of organisms, yet their molecular sites of action remain poorly characterized. Pentameric ligand-gated ion channels, long implicated in important direct effects of alcohol and anesthetic binding, have recently been illuminated in renewed detail thanks to the determination of atomic-resolution structures of several family members from lower organisms. These structures provide valuable models for understanding and developing anesthetic agents and for allosteric modulation in general. This review surveys progress in this field from function to structure and back again, outlining early evidence for relevant modulation of pentameric ligand-gated ion channels and the development of early structural models for ion channel function and modulation. We highlight insights and challenges provided by recent crystal structures and resulting simulations, as well as opportunities for translation of these newly detailed models back to behavior and therapy. PMID:24515646

Emergency Victim Care. A Training Manual for Emergency Medical Technicians. Module 3--Anatomy and Physiology. Revised.

ERIC Educational Resources Information Center

Ohio State Dept. of Education, Columbus. Div. of Vocational Education.

This student manual, the third in a set of 14 modules, is designed to train emergency medical technicians (EMTs) in Ohio. The module contains one section covering the following topics: general anatomical terms, the body cavities and contents, the integumentary system, the skeletal system, the muscular system, the nervous system, the respiratory…

General-Purpose Heat Source Safety Verification Test Program: Edge-on flyer plate tests

NASA Astrophysics Data System (ADS)

George, T. G.

1987-03-01

The radioisotope thermoelectric generator (RTG) that will supply power for the Galileo and Ulysses space missions contains 18 General-Purpose Heat Source (GPHS) modules. The GPHS modules provide power by transmitting the heat of Pu-238 alpha-decay to an array of thermoelectric elements. Each module contains four Pu-238O2-fueled clads and generates 250 W(t). Because the possibility of a launch vehicle explosion always exists, and because such an explosion could generate a field of high-energy fragments, the fueled clads within each GPHS module must survive fragment impact. The edge-on flyer plate tests were included in the Safety Verification Test series to provide information on the module/clad response to the impact of high-energy plate fragments. The test results indicate that the edge-on impact of a 3.2-mm-thick, aluminum-alloy (2219-T87) plate traveling at 915 m/s causes the complete release of fuel from capsules contained within a bare GPHS module, and that the threshold velocity sufficient to cause the breach of a bare, simulant-fueled clad impacted by a 3.5-mm-thick, aluminum-alloy (5052-TO) plate is approximately 140 m/s.

Modulation of the Intracortical LFP during Action Execution and Observation

PubMed Central

Vigneswaran, Ganesh; Philipp, Roland; Lemon, Roger N.; Kraskov, Alexander

2015-01-01

The activity of mirror neurons in macaque ventral premotor cortex (PMv) and primary motor cortex (M1) is modulated by the observation of another's movements. This modulation could underpin well documented changes in EEG/MEG activity indicating the existence of a mirror neuron system in humans. Because the local field potential (LFP) represents an important link between macaque single neuron and human noninvasive studies, we focused on mirror properties of intracortical LFPs recorded in the PMv and M1 hand regions in two macaques while they reached, grasped and held different objects, or observed the same actions performed by an experimenter. Upper limb EMGs were recorded to control for covert muscle activity during observation. The movement-related potential (MRP), investigated as intracortical low-frequency LFP activity (<9 Hz), was modulated in both M1 and PMv, not only during action execution but also during action observation. Moreover, the temporal LFP modulations during execution and observation were highly correlated in both cortical areas. Beta power in both PMv and M1 was clearly modulated in both conditions. Although the MRP was detected only during dynamic periods of the task (reach/grasp/release), beta decreased during dynamic and increased during static periods (hold). Comparison of LFPs for different grasps provided evidence for partially nonoverlapping networks being active during execution and observation, which might be related to different inputs to motor areas during these conditions. We found substantial information about grasp in the MRP corroborating its suitability for brain–machine interfaces, although information about grasp was generally low during action observation. PMID:26041914

Intramolecular co-action of two independent photosensory modules in the fern phytochrome 3.

PubMed

Kanegae, Takeshi

2015-01-01

Fern phytochrome3/neochrome1 (phy3/neo1) is a chimeric photoreceptor composed of a phytochrome-chromophore binding domain and an almost full-length phototropin. phy3 thus contains two different light-sensing modules; a red/far-red light receptor phytochrome and a blue light receptor phototropin. phy3 induces both red light- and blue light-dependent phototropism in phototropin-deficient Arabidopsis thaliana (phot1 phot2) seedlings. The red-light response is dependent on the phytochrome module of phy3, and the blue-light response is dependent on the phototropin module. We recently showed that both the phototropin-sensing module and the phytochrome-sensing module mediate the blue light-dependent phototropic response. Particularly under low-light conditions, these two light-sensing modules cooperate to induce the blue light-dependent phototropic response. This intramolecular co-action of two independent light-sensing modules in phy3 enhances light sensitivity, and perhaps allowed ferns to adapt to the low-light canopy conditions present in angiosperm forests.

TRANSVERSE MODE ELECTRO-OPTIC MATERIALS.

DTIC Science & Technology

electro - optic modulators presently used are crystals such as KDP which exhibit a longitudinal electro - optic effect. It has been demonstrated that a more efficient modulator can be produced when a crystal having a transverse electro - optic effect is employed. Generally these crystals are produced either from the melt or from fluxes. Since melt grown crystals must be cooled through several hundred degrees and often must undergo phase transitions, these crystals are generally highly strained. Flux grown crystals are also

Teaching geriatric medicine at the Queen's University of Belfast.

PubMed

Stout, R W

1983-01-01

Undergraduate teaching at the Queen's University, Belfast, takes place in the fourth year of a five year curriculum. It lasts three weeks and this is divided into two parts. First, held within the university department, is topic-based teaching including seminars, discussions, case histories and visits. The second phase of two weeks consists of attachment of two to four students to geriatric medical units both in and outside Belfast. The whole of this module is situated within a combined course involving community medicine, general practice, geriatric medicine and mental health lasting 12 weeks and involving one-third of the year of 150 students each time. In addition to the three weeks teaching in geriatrics, joint discussion groups are held.

A scintillator geometry suitable for very small PET gantries

NASA Astrophysics Data System (ADS)

Gonzalez, A. J.; Gonzalez-Montoro, A.; Aguilar, A.; Cañizares, G.; Martí, R.; Iranzo, S.; Lamprou, E.; Sanchez, S.; Sanchez, F.; Benlloch, J. M.

2017-12-01

In this work we are describing a novel approach to the scintillator crystal configuration as used in nuclear medicine imaging. Our design is related to the coupling in one PET module of the two separate crystal configurations used so far there: monolithic and crystal arrays. The particular design we have studied is based on a two-layer scintillator approach (hybrid) composed of a monolithic LYSO crystal (5-6 mm thickness) and a LYSO crystal array with 4-5 mm height (0.8 and 1 mm pixels). We show here the detector block performance, in terms of spatial, energy and DOI information, to be used as a module in the design of PET scanners. The design we propose allows one to achieve accurate three-dimensional spatial resolution (including DOI information) while assuring high detection efficiency at reasonable cost. Moreover, the proposed design improves the spatial response uniformity across the whole detector module, and especially at the edge region. The crystal arrays are mounted in the front and were well resolved. The monolithic crystal inserted between crystal array and the photosensor, provided measured FWHM resolution as good as 1.5-1.7 mm including the 1 mm source size. The monolithic block achieved a DOI resolution (FWHM) nearing 3 mm. We compared these results with an approach in which we use a single monolithic block with total volume equals to the hybrid approach. In general, comparable performances were obtained.

Development and testing of an implementation strategy for a complex housing intervention: protocol for a mixed methods study.

PubMed

Watson, Dennis P; Young, Jeani; Ahonen, Emily; Xu, Huiping; Henderson, Macey; Shuman, Valery; Tolliver, Randi

2014-10-17

There is currently a lack of scientifically designed and tested implementation strategies. Such strategies are particularly important for highly complex interventions that require coordination between multiple parts to be successful. This paper presents a protocol for the development and testing of an implementation strategy for a complex intervention known as the Housing First model (HFM). Housing First is an evidence-based practice for chronically homeless individuals demonstrated to significantly improve a number of outcomes. Drawing on practices demonstrated to be useful in implementation and e-learning theory, our team is currently adapting a face-to-face implementation strategy so that it can be delivered over a distance. Research activities will be divided between Chicago and Central Indiana, two areas with significantly different barriers to HFM implementation. Ten housing providers (five from Chicago and five from Indiana) will be recruited to conduct an alpha test of each of four e-learning modules as they are developed. Providers will be requested to keep a detailed log of their experience completing the modules and participate in one of two focus groups. After refining the modules based on alpha test results, we will test the strategy among a sample of four housing organizations (two from Chicago and two from Indiana). We will collect and analyze both qualitative and quantitative data from administration and staff. Measures of interest include causal factors affecting implementation, training outcomes, and implementation outcomes. This project is an important first step in the development of an evidence-based implementation strategy to increase scalability and impact of the HFM. The project also has strong potential to increase limited scientific knowledge regarding implementation strategies in general.

Z2×Z2 generalizations of 𝒩 =2 super Schrödinger algebras and their representations

NASA Astrophysics Data System (ADS)

Aizawa, N.; Segar, J.

2017-11-01

We generalize the real and chiral N =2 super Schrödinger algebras to Z2×Z2-graded Lie superalgebras. This is done by D-module presentation, and as a consequence, the D-module presentations of Z2×Z2-graded superalgebras are identical to the ones of super Schrödinger algebras. We then generalize the calculus over the Grassmann number to Z2×Z2 setting. Using it and the standard technique of Lie theory, we obtain a vector field realization of Z2×Z2-graded superalgebras. A vector field realization of the Z2×Z2 generalization of N =1 super Schrödinger algebra is also presented.

Comparison of tungsten films grown by CVD and hot-wire assisted atomic layer deposition in a cold-wall reactor

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

Yang, Mengdi, E-mail: M.Yang@utwente.nl; Aarnink, Antonius A. I.; Kovalgin, Alexey Y.

2016-01-15

In this work, the authors developed hot-wire assisted atomic layer deposition (HWALD) to deposit tungsten (W) with a tungsten filament heated up to 1700–2000 °C. Atomic hydrogen (at-H) was generated by dissociation of molecular hydrogen (H{sub 2}), which reacted with WF{sub 6} at the substrate to deposit W. The growth behavior was monitored in real time by an in situ spectroscopic ellipsometer. In this work, the authors compare samples with tungsten grown by either HWALD or chemical vapor deposition (CVD) in terms of growth kinetics and properties. For CVD, the samples were made in a mixture of WF{sub 6} and molecularmore » or atomic hydrogen. Resistivity of the WF{sub 6}-H{sub 2} CVD layers was 20 μΩ·cm, whereas for the WF{sub 6}-at-H-CVD layers, it was 28 μΩ·cm. Interestingly, the resistivity was as high as 100 μΩ·cm for the HWALD films, although the tungsten films were 99% pure according to x-ray photoelectron spectroscopy. X-ray diffraction reveals that the HWALD W was crystallized as β-W, whereas both CVD films were in the α-W phase.« less

Investigations on structural and electrical parameters of p-Si/ MgxZn1-xO thin film heterojunction diodes grown by RF magnetron sputtering technique

NASA Astrophysics Data System (ADS)

Singh, Satyendra Kumar; Hazra, Purnima

2018-05-01

This work reports fabrication and characterization of p-Si/ MgxZn1-xO thin film heterojunction diodes grown by RF magnetron sputtering technique. In this work, ZnO powder was mixed with MgO powder at per their weight percentage from 0 to 10% to prepare MgxZn1-xO target. The microstructural, surface morphological and optical properties of as-deposited p-Si/MgxZn1-xO heterostructure thin films have been studied using X-ray Diffraction, atomic force microscopy and variable angle ellipsometer. XRD spectra exhibit that undoped ZnO thin films has preferred crystal orientation in (002) plane. However, with increase in Mg-doping, ZnO (101) crystal plane is enhanced progressively due to phase segregation, even though preferred growth orientation of ZnO crystals is still towards (002) plane. The electrical characteristics of Si/ MgxZn1-xO heterojunction diodes with large area Al/Ti ohmic contacts are evaluated using semiconductor parameter analyzer. With rectification ratio of 27894, reverse saturation current of 20.5 nA and barrier height of 0.724 eV, Si/Mg0.5Zn0.95O thin film heterojunction diode is believed to have potential to be used in wider bandgap nanoelectronic device applications.

Effect of surface oxidation on emissivity properties of pure aluminum in the near infrared region

NASA Astrophysics Data System (ADS)

Zhang, Kaihua; Yu, Kun; Liu, Yufang; Zhao, Yuejin

2017-08-01

Emissivity is a basic thermo physical property of materials and determines the precision of radiation thermometry. The aim of this paper is to study the effect of surface oxidation on the infrared emissivity properties of pure aluminum. The emissivity data presented in this study covers the spectral range between 0.8 and 2.2 µm and temperatures from 473 to 873 K. The samples with different oxidation time were prepared under a controlled environment. The morphology and composition of the samples were characterized by metallographic microscope and XRD techniques before and after oxidation. The thickness of oxide film with different oxidation time was accurately measured by spectroscopic ellipsometer and a parabolic growth was found. In addition, the interference model of an oxidized metal substrate is established to explain the influence of the oxide film thickness on the emissivity. The thickness of oxide film when the interference effect occurs was calculated according to the interference model. The data shows that the maximum value measured was less than the thickness value at the first order constructive interference. Neither peaks nor valleys were observed in emissivity measurements with different oxidation time at 873 K, which could be related to the thin oxide film on sample surface.

Materials, structures, and devices for high-speed electronics

NASA Technical Reports Server (NTRS)

Woollam, John A.; Snyder, Paul G.

1992-01-01

Advances in materials, devices, and instrumentation made under this grant began with ex-situ null ellipsometric measurements of simple dielectric films on bulk substrates. Today highly automated and rapid spectroscopic ellipsometers are used for ex-situ characterization of very complex multilayer epitaxial structures. Even more impressive is the in-situ capability, not only for characterization but also for the actual control of the growth and etching of epitaxial layers. Spectroscopic ellipsometry has expanded from the research lab to become an integral part of the production of materials and structures for state of the art high speed devices. Along the way, it has contributed much to our understanding of the growth characteristics and material properties. The following areas of research are summarized: Si3N4 on GaAs, null ellipsometry; diamondlike carbon films; variable angle spectroscopic ellipsometry (VASE) development; GaAs-AlGaAs heterostructures; Ta-Cu diffusion barrier films on GaAs; GaAs-AlGaAs superlattices and multiple quantum wells; superconductivity; in situ elevated temperature measurements of III-V's; optical constants of thermodynamically stable InGaAs; doping dependence of optical constants of GaAs; in situ ellipsometric studies of III-V epitaxial growth; photothermal spectroscopy; microellipsometry; and Si passivation and Si/SiGe strained-layer superlattices.

Mode-splitting of a non-polarizing guided mode resonance filter by substrate overetching effect

NASA Astrophysics Data System (ADS)

Saleem, Muhammad Rizwan; Honkanen, Seppo; Turunen, Jari

2014-03-01

We investigate substrate overetch effect on resonance properties of sub-wavelength titanium oxide (TiO2) Guided Mode Resonance Filters (TiO2-GMRFs). The TiO2-GMRF is designed and fabricated to possess a non-polarizing behavior, which is strongly dependent on substrate (fused silica) overetch depth. For non-polarizing gratings at resonance, TE- and TM-modes have the same propagation constants. However, an overetch substrate effect results in splitting of the degenerate modes, which is studied theoretically and experimentally. The TiO2-SiO2 GMRFs are designed by Fourier Modal method (FMM) based on the rigorous calculation of electromagnetic diffraction theory at a designed wavelength of 850 nm. The TiO2-SiO2 gratings are fabricated by Atomic Layer Deposition (ALD), Electron Beam Lithography (EBL), and Reactive Ion Etching (RIE), and they are subsequently characterized structurally by Scanning Electron Microscopy (SEM) and optically by a spectroscopic ellipsometer. Several grating samples are fabricated by gradually increasing the overetch depth into fused silica and measuring the extent of TE- and TM-mode-splitting. A close agreement between the calculated and experimentally measured resonance wavelength spectral shift is found to describe the mode splitting of non-polarizing gratings.

Long Duration Space Materials Exposure (LDSE)

NASA Technical Reports Server (NTRS)

Allen, David; Schmidt, Robert

1992-01-01

The Center on Materials for Space Structures (CMSS) at Case Western Reserve University is one of seventeen Commercial Centers for the Development of Space. It was founded to: (1) produce and evaluate materials for space structures; (2) develop passive and active facilities for materials exposure and analysis in space; and (3) develop improved material systems for space structures. A major active facility for materials exposure is proposed to be mounted on the exterior truss of the Space Station Freedom (SSF). This Long Duration Space Materials Exposure (LDSE) experiment will be an approximately 6 1/2 ft. x 4 ft. panel facing into the velocity vector (RAM) to provide long term exposure (up to 30 years) to atomic oxygen, UV, micro meteorites, and other low earth orbit effects. It can expose large or small active (instrumented) or passive samples. These samples may be mounted in a removable Materials Flight Experiment (MFLEX) carrier which may be periodically brought into the SSF for examination by CMSS's other SSF facility, the Space Materials Evaluation Facility (SMEF), which will contain a Scanning Electron Microscope, a Variable Angle & Scanning Ellipsometer, a Fourier Transform Infrared Spectrometer, and other analysis equipment. These facilities will allow commercial firms to test their materials in space and promptly obtain information on their materials survivability in the LEO environment.

ELLIPSOMETRIC MEASUREMENTS OF THE THERMAL STABILITY OF ALTERNATIVE FUELS

PubMed Central

Nash, Leigh; Klettlinger, Jennifer; Vasu, Subith

2017-01-01

Thermal stability is an important characteristic of alternative fuels that must be evaluated before they can be used in aviation engines. Thermal stability refers to the degree to which a fuel breaks down when it is heated prior to combustion. This characteristic is of great importance to the effectiveness of the fuel as a coolant and to the engine’s combustion performance. The thermal stability of Sasol IPK, a synthetic alternative to Jet-A, with varying levels of naphthalene has been studied on aluminum and stainless steel substrates at 300 to 400 °C. This was conducted using a spectroscopic ellipsometer to measure the thickness of deposits left on the heated substrates. Ellipsometry is an optical technique that measures the changes in a light beam’s polarization and intensity after it reflects from a thin film to determine the film’s physical and optical properties. It was observed that, as would be expected, increasing the temperature minimally increased the deposit thickness for a constant concentration of naphthalene on both substrates. The repeatability of these measurements was verified using multiple trials at identical test conditions. Lastly, the effect of increasing the naphthalene concentration at a constant temperature was found to also minimally increase the deposit thickness. PMID:28966427

Surface plasmon resonance and nonlinear optical behavior of pulsed laser-deposited semitransparent nanostructured copper thin films

NASA Astrophysics Data System (ADS)

Kesarwani, Rahul; Khare, Alika

2018-06-01

In this paper, surface plasmon resonance (SPR) and nonlinear optical properties of semitransparent nanostructured copper thin films fabricated on the glass substrate at 400 °C by pulsed laser deposition technique are reported. The thickness, linear absorption coefficient and linear refractive index of the films were measured by spectroscopic ellipsometer. The average particle size as measured via atomic force microscope was in the range of 12.84-26.02 nm for the deposition time ranging from 5 to 10 min, respectively. X-ray diffraction spectra revealed the formation of Cu (111) and Cu (200) planes. All these thin films exhibited broad SPR peak. The third-order optical nonlinearity of all the samples was investigated via modified z-scan technique using cw laser at a wavelength of 632.8 nm. The open aperture z-scan spectra of Cu thin film deposited for 5 min duration exhibited reverse saturation absorption whereas all the other samples displayed saturation absorption behavior. The nonlinear refractive index coefficient of these films showed a positive sign having the magnitude of the order of 10- 4 cm/W. The real and imaginary parts of susceptibilities were also calculated from the z-scan data and found to be of the order of 10- 6 esu.

Carbon nanotube fiber terahertz polarizer

NASA Astrophysics Data System (ADS)

Zubair, Ahmed; Tsentalovich, Dmitri E.; Young, Colin C.; Heimbeck, Martin S.; Everitt, Henry O.; Pasquali, Matteo; Kono, Junichiro

2016-04-01

Conventional, commercially available terahertz (THz) polarizers are made of uniformly and precisely spaced metallic wires. They are fragile and expensive, with performance characteristics highly reliant on wire diameters and spacings. Here, we report a simple and highly error-tolerant method for fabricating a freestanding THz polarizer with nearly ideal performance, reliant on the intrinsically one-dimensional character of conduction electrons in well-aligned carbon nanotubes (CNTs). The polarizer was constructed on a mechanical frame over which we manually wound acid-doped CNT fibers with ultrahigh electrical conductivity. We demonstrated that the polarizer has an extinction ratio of ˜-30 dB with a low insertion loss (<0.5 dB) throughout a frequency range of 0.2-1.1 THz. In addition, we used a THz ellipsometer to measure the Müller matrix of the CNT-fiber polarizer and found comparable attenuation to a commercial metallic wire-grid polarizer. Furthermore, based on the classical theory of light transmission through an array of metallic wires, we demonstrated the most striking difference between the CNT-fiber and metallic wire-grid polarizers: the latter fails to work in the zero-spacing limit, where it acts as a simple mirror, while the former continues to work as an excellent polarizer even in that limit due to the one-dimensional conductivity of individual CNTs.

Integrating Software Modules For Robot Control

NASA Technical Reports Server (NTRS)

Volpe, Richard A.; Khosla, Pradeep; Stewart, David B.

1993-01-01

Reconfigurable, sensor-based control system uses state variables in systematic integration of reusable control modules. Designed for open-architecture hardware including many general-purpose microprocessors, each having own local memory plus access to global shared memory. Implemented in software as extension of Chimera II real-time operating system. Provides transparent computing mechanism for intertask communication between control modules and generic process-module architecture for multiprocessor realtime computation. Used to control robot arm. Proves useful in variety of other control and robotic applications.

Method & apparatus for monitoring plasma processing operations

DOEpatents

Smith, Jr., Michael Lane; Ward, Pamela Denise; Stevenson, Joel O'Don

2004-10-19

The invention generally relates to various aspects of a plasma process and, more specifically, to the monitoring of such plasma processes. One aspect relates to a plasma monitoring module that may be adjusted in at least some manner so as to re-evaluate a previously monitored plasma process. For instance, optical emissions data on a plasma process that was previously monitored by the plasma monitoring module may be replayed through the plasma monitoring module after making at least one adjustment in relation to the plasma monitoring module.

VINE-A NUMERICAL CODE FOR SIMULATING ASTROPHYSICAL SYSTEMS USING PARTICLES. I. DESCRIPTION OF THE PHYSICS AND THE NUMERICAL METHODS

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

Wetzstein, M.; Nelson, Andrew F.; Naab, T.

2009-10-01

We present a numerical code for simulating the evolution of astrophysical systems using particles to represent the underlying fluid flow. The code is written in Fortran 95 and is designed to be versatile, flexible, and extensible, with modular options that can be selected either at the time the code is compiled or at run time through a text input file. We include a number of general purpose modules describing a variety of physical processes commonly required in the astrophysical community and we expect that the effort required to integrate additional or alternate modules into the code will be small. Inmore » its simplest form the code can evolve the dynamical trajectories of a set of particles in two or three dimensions using a module which implements either a Leapfrog or Runge-Kutta-Fehlberg integrator, selected by the user at compile time. The user may choose to allow the integrator to evolve the system using individual time steps for each particle or with a single, global time step for all. Particles may interact gravitationally as N-body particles, and all or any subset may also interact hydrodynamically, using the smoothed particle hydrodynamic (SPH) method by selecting the SPH module. A third particle species can be included with a module to model massive point particles which may accrete nearby SPH or N-body particles. Such particles may be used to model, e.g., stars in a molecular cloud. Free boundary conditions are implemented by default, and a module may be selected to include periodic boundary conditions. We use a binary 'Press' tree to organize particles for rapid access in gravity and SPH calculations. Modules implementing an interface with special purpose 'GRAPE' hardware may also be selected to accelerate the gravity calculations. If available, forces obtained from the GRAPE coprocessors may be transparently substituted for those obtained from the tree, or both tree and GRAPE may be used as a combination GRAPE/tree code. The code may be run without modification on single processors or in parallel using OpenMP compiler directives on large-scale, shared memory parallel machines. We present simulations of several test problems, including a merger simulation of two elliptical galaxies with 800,000 particles. In comparison to the Gadget-2 code of Springel, the gravitational force calculation, which is the most costly part of any simulation including self-gravity, is {approx}4.6-4.9 times faster with VINE when tested on different snapshots of the elliptical galaxy merger simulation when run on an Itanium 2 processor in an SGI Altix. A full simulation of the same setup with eight processors is a factor of 2.91 faster with VINE. The code is available to the public under the terms of the Gnu General Public License.« less

Vine—A Numerical Code for Simulating Astrophysical Systems Using Particles. I. Description of the Physics and the Numerical Methods

NASA Astrophysics Data System (ADS)

Wetzstein, M.; Nelson, Andrew F.; Naab, T.; Burkert, A.

2009-10-01

We present a numerical code for simulating the evolution of astrophysical systems using particles to represent the underlying fluid flow. The code is written in Fortran 95 and is designed to be versatile, flexible, and extensible, with modular options that can be selected either at the time the code is compiled or at run time through a text input file. We include a number of general purpose modules describing a variety of physical processes commonly required in the astrophysical community and we expect that the effort required to integrate additional or alternate modules into the code will be small. In its simplest form the code can evolve the dynamical trajectories of a set of particles in two or three dimensions using a module which implements either a Leapfrog or Runge-Kutta-Fehlberg integrator, selected by the user at compile time. The user may choose to allow the integrator to evolve the system using individual time steps for each particle or with a single, global time step for all. Particles may interact gravitationally as N-body particles, and all or any subset may also interact hydrodynamically, using the smoothed particle hydrodynamic (SPH) method by selecting the SPH module. A third particle species can be included with a module to model massive point particles which may accrete nearby SPH or N-body particles. Such particles may be used to model, e.g., stars in a molecular cloud. Free boundary conditions are implemented by default, and a module may be selected to include periodic boundary conditions. We use a binary "Press" tree to organize particles for rapid access in gravity and SPH calculations. Modules implementing an interface with special purpose "GRAPE" hardware may also be selected to accelerate the gravity calculations. If available, forces obtained from the GRAPE coprocessors may be transparently substituted for those obtained from the tree, or both tree and GRAPE may be used as a combination GRAPE/tree code. The code may be run without modification on single processors or in parallel using OpenMP compiler directives on large-scale, shared memory parallel machines. We present simulations of several test problems, including a merger simulation of two elliptical galaxies with 800,000 particles. In comparison to the Gadget-2 code of Springel, the gravitational force calculation, which is the most costly part of any simulation including self-gravity, is ~4.6-4.9 times faster with VINE when tested on different snapshots of the elliptical galaxy merger simulation when run on an Itanium 2 processor in an SGI Altix. A full simulation of the same setup with eight processors is a factor of 2.91 faster with VINE. The code is available to the public under the terms of the Gnu General Public License.

Proposal of DCS-OFDM-PON upstream transmission with intensity modulator and collective self-coherent detection

NASA Astrophysics Data System (ADS)

Zhang, Jing; Yang, Heming; Zhao, Difu; Qiu, Kun

2016-07-01

We introduce digital coherent superposition (DCS) into optical access network and propose a DCS-OFDM-PON upstream transmission scheme using intensity modulator and collective self-coherent detection. The generated OFDM signal is real based on Hermitian symmetry, which can be used to estimate the common phase error (CPE) by complex conjugate subcarrier pairs without any pilots. In simulation, we transmit an aggregated 40 Gb/s optical OFDM signal from two ONUs. The transmission performance with DCS is slightly better after 25 km transmission without relative transmission time delay. The fiber distance for different ONUs to RN are not same in general and there is relative transmission time delay between ONUs, which causes inter-carrier-interference (ICI) power increasing and degrades the transmission performance. The DCS can mitigate the ICI power and the DCS-OFDM-PON upstream transmission outperforms the conventional OFDM-PON. The CPE estimation is by using two pairs of complex conjugate subcarriers without redundancy. The power variation can be 9 dB in DCS-OFDM-PON, which is enough to tolerate several kilometers fiber length difference between the ONUs.

Design considerations and validation of the MSTAR absolute metrology system

NASA Astrophysics Data System (ADS)

Peters, Robert D.; Lay, Oliver P.; Dubovitsky, Serge; Burger, Johan; Jeganathan, Muthu

2004-08-01

Absolute metrology measures the actual distance between two optical fiducials. A number of methods have been employed, including pulsed time-of-flight, intensity-modulated optical beam, and two-color interferometry. The rms accuracy is currently limited to ~5 microns. Resolving the integer number of wavelengths requires a 1-sigma range accuracy of ~0.1 microns. Closing this gap has a large pay-off: the range (length measurement) accuracy can be increased substantially using the unambiguous optical phase. The MSTAR sensor (Modulation Sideband Technology for Absolute Ranging) is a new system for measuring absolute distance, capable of resolving the integer cycle ambiguity of standard interferometers, and making it possible to measure distance with sub-nanometer accuracy. In this paper, we present recent experiments that use dispersed white light interferometry to independently validate the zero-point of the system. We also describe progress towards reducing the size of optics, and stabilizing the laser wavelength for operation over larger target ranges. MSTAR is a general-purpose tool for conveniently measuring length with much greater accuracy than was previously possible, and has a wide range of possible applications.

An installed nacelle design code using a multiblock Euler solver. Volume 2: User guide

NASA Technical Reports Server (NTRS)

Chen, H. C.

1992-01-01

This is a user manual for the general multiblock Euler design (GMBEDS) code. The code is for the design of a nacelle installed on a geometrically complex configuration such as a complete airplane with wing/body/nacelle/pylon. It consists of two major building blocks: a design module developed by LaRC using directive iterative surface curvature (DISC); and a general multiblock Euler (GMBE) flow solver. The flow field surrounding a complex configuration is divided into a number of topologically simple blocks to facilitate surface-fitted grid generation and improve flow solution efficiency. This user guide provides input data formats along with examples of input files and a Unix script for program execution in the UNICOS environment.

Systems Characterization of Combustor Instabilities With Controls Design Emphasis

NASA Technical Reports Server (NTRS)

Kopasakis, George

2004-01-01

This effort performed test data analysis in order to characterize the general behavior of combustor instabilities with emphasis on controls design. The analysis is performed on data obtained from two configurations of a laboratory combustor rig and from a developmental aero-engine combustor. The study has characterized several dynamic behaviors associated with combustor instabilities. These are: frequency and phase randomness, amplitude modulations, net random phase walks, random noise, exponential growth and intra-harmonic couplings. Finally, the very cause of combustor instabilities was explored and it could be attributed to a more general source-load type impedance interaction that includes the thermo-acoustic coupling. Performing these characterizations on different combustors allows for more accurate identification of the cause of these phenomena and their effect on instability.

A proposed computer diagnostic system for malignant melanoma (CDSMM).

PubMed

Shao, S; Grams, R R

1994-04-01

This paper describes a computer diagnostic system for malignant melanoma. The diagnostic system is a rule base system based on image analyses and works under the PC windows environment. It consists of seven modules: I/O module, Patient/Clinic database, image processing module, classification module, rule base module and system control module. In the system, the image analyses are automatically carried out, and database management is efficient and fast. Both final clinic results and immediate results from various modules such as measured features, feature pictures and history records of the disease lesion can be presented on screen or printed out from each corresponding module or from the I/O module. The system can also work as a doctor's office-based tool to aid dermatologists with details not perceivable by the human eye. Since the system operates on a general purpose PC, it can be made portable if the I/O module is disconnected.

Design Considerations of a Novel Two-Beam Accelerator

NASA Astrophysics Data System (ADS)

Luginsland, John William

This thesis reports the design study of a new type of charged particle accelerator called the Twobetron. The accelerator consists of two beams of electrons traveling through a series of pillbox cavities. The power of a high current annular beam excites an electromagnetic mode in the cavities, which, in turn, drives a low current on-axis pencil beam to high energy. We focus on the design considerations that would make use of existing pulsed power systems, for a proof-of-principle experiment. Potential applications of this new device include radiotherapy, materials processing, and high energy accelerators. The first phase of the research involves analytic description of the accelerating process. This reveals the problem of phase slippage. Derbenev's proposed cure of beam radius modulation is analyzed. Further studies include the effect of initial phase and secondary beam loading. Scaling laws to characterize the Twobetron's performance are derived. Computer simulation is performed to produce a self-consistent analysis of the dynamics of the space charge and its interaction with the accelerator structure. Particle -in-cell simulations answer several questions concerning beam stability, cavity modes, and the nature of the structure. Specifically, current modulation on the primary beam is preserved in the simulations. However, these simulations also revealed that mode competition and significant cavity coupling are serious issues that need to be addressed. Also considered is non-axisymmetric instability on the driver beam of the Twobetron, in particular, the beam breakup instability (BBU), which is known to pose a serious threat to linear accelerators in general. We extend the classical analysis of BBU to annular beams. The effect of higher order non-axisymmetric modes is also examined. It is shown that annular beams are more stable than pencil beams to BBU in general. Our analysis also reveals that the rf magnetic field is more important than the rf electric field in contributing to BBU growth. We next address the issue of primary beam modulation. Both particle-in-cell and analytic investigation showed that the usual relativistic klystron amplifiers (RKA) mechanism cannot provide full beam modulation at convenient levels of external rf drive. However, the recent discovery at the Air Force Phillips Laboratory of the injection locked relativistic klystron oscillator suggests that electromagnetic feedback between the driver cavity and the booster cavity might significantly enhance the current modulation. A simple model is constructed to analyze this cavity coupling and its mutual interaction with the primary beam. Quantitative agreement is found between our model and the Phillips Laboratory experiments. This analysis suggests that significant current modulation on the primary beam may be achieved with low level external rf drive.

Frequency response control of semiconductor laser by using hybrid modulation scheme.

PubMed

Mieda, Shigeru; Yokota, Nobuhide; Isshiki, Ryuto; Kobayashi, Wataru; Yasaka, Hiroshi

2016-10-31

A hybrid modulation scheme that simultaneously applies the direct current modulation and intra-cavity loss modulation to a semiconductor laser is proposed. Both numerical calculations using rate equations and experiments using a fabricated laser show that the hybrid modulation scheme can control the frequency response of the laser by changing a modulation ratio and time delay between the two modulations. The modulation ratio and time delay provide the degree of signal mixing of the two modulations and an optimum condition is found when a non-flat frequency response for the intra-cavity loss modulation is compensated by that for the direct current modulation. We experimentally confirm a 8.64-dB improvement of the modulation sensitivity at 20 GHz compared with the pure direct current modulation with a 0.7-dB relaxation oscillation peak.

A characterization of low luminance static and dynamic modulation transfer function curves for P-1, P-43, and P-53 phosphorus

NASA Astrophysics Data System (ADS)

Beasley, Howard H.; Martin, John S.; Klymenko, Victor; Harding, Thomas H.; Verona, Robert W.; Rash, Clarence E.

1995-07-01

A counterphase modulation technique is used to measure the static and dynamic modulation transfer functions for three phosphorus of current interest to U.S. Army aviation helmet-mounted displays (P-1, P-43, and P-53). A family of modulation transfer curves, one for each temporal frequency, is presented for each phosphorus. The measured MFT curves generally support the supposition that phosphorus persistence is a critical parameter in the ability of a CRT display to accurately reproduce contrast modulation transfer in dynamic environments.

Antimicrobial and Virulence-Modulating Effects of Clove Essential Oil on the Foodborne Pathogen Campylobacter jejuni.

PubMed

Kovács, Judit K; Felső, Péter; Makszin, Lilla; Pápai, Zoltán; Horváth, Györgyi; Ábrahám, Hajnalka; Palkovics, Tamás; Böszörményi, Andrea; Emődy, Levente; Schneider, György

2016-10-15

Our study investigated the antimicrobial action of clove (Syzygium aromaticum) essential oil (EO) on the zoonotic pathogen Campylobacter jejuni After confirming the clove essential oil's general antibacterial effect, we analyzed the reference strain Campylobacter jejuni NCTC 11168. Phenotypic, proteomic, and transcriptomic methods were used to reveal changes in cell morphology and functions when exposed to sublethal concentrations of clove EO. The normally curved cells showed markedly straightened and shrunken morphology on the scanning electron micrographs as a result of stress. Although, oxidative stress, as a generally accepted response to essential oils, was also present, the dominance of a general stress response was demonstrated by reverse transcription-PCR (RT-PCR). The results of RT-PCR and two-dimensional (2D) PAGE revealed that clove oil perturbs the expression of virulence-associated genes taking part in the synthesis of flagella, PEB1, PEB4, lipopolysaccharide (LPS), and serine protease. Loss of motility was also detected by a phenotypic test. Bioautographic analysis revealed that besides its major component, eugenol, at least four other spots of clove EO possessed bactericidal activity against C. jejuni Our findings show that clove EO has a marked antibacterial and potential virulence-modulating effect on C. jejuni IMPORTANCE: This study demonstrates that the components of clove essential oil influence not only the expression of general stress genes but also the expression of virulence-associated genes. Based on this finding, alternative strategies can be worked on to control this important foodborne pathogen. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Autonomic markers associated with generalized social phobia symptoms: heart rate variability and salivary alpha-amylase.

PubMed

García-Rubio, María J; Espín, Laura; Hidalgo, Vanesa; Salvador, Alicia; Gómez-Amor, Jesús

2017-01-01

The study of autonomic nervous system changes associated with generalized social phobia (GSP) disorder has increased in recent years, showing contradictory results. The present study aimed to evaluate how young people with GSP reacted before, during, and after exposure to the Trier Stress Social Test (TSST), focusing on their autonomic changes (heart rate variability (HRV) and salivary alpha-amylase (sAA)) compared to a control group (non-GSP). Some psychological variables were also considered. Sex was specifically studied as a possible modulator of autonomic fluctuations and psychological state. Eighty young people were randomly distributed into two counterbalanced situations: stress condition (N = 18 and 21 for GSP and non-GSP, respectively) and control condition (N = 21 and 20 for GSP and non-GSP, respectively), where cardiovascular variables were continuously recorded. Psychological questionnaires about mood and perceived stress were filled out, and five saliva samples were collected to analyze sAA. GSP participants showed higher values on low- and high-frequency ratios (HR domains), compared to non-GSP people, during exposure to the TSST, but no differences were observed after the stressor. Furthermore, the two groups did not differ in sAA. Importantly, positive affect in GSP participants was modulated by sex. The present study suggests that the balance between high- and low-frequency domains of HRV is a key cardiovascular marker reflecting the stress response of GSP people, as well the importance of sex in positive affect when facing a stressful situation.

Time-frequency analysis of time-varying modulated signals based on improved energy separation by iterative generalized demodulation

NASA Astrophysics Data System (ADS)

Feng, Zhipeng; Chu, Fulei; Zuo, Ming J.

2011-03-01

Energy separation algorithm is good at tracking instantaneous changes in frequency and amplitude of modulated signals, but it is subject to the constraints of mono-component and narrow band. In most cases, time-varying modulated vibration signals of machinery consist of multiple components, and have so complicated instantaneous frequency trajectories on time-frequency plane that they overlap in frequency domain. For such signals, conventional filters fail to obtain mono-components of narrow band, and their rectangular decomposition of time-frequency plane may split instantaneous frequency trajectories thus resulting in information loss. Regarding the advantage of generalized demodulation method in decomposing multi-component signals into mono-components, an iterative generalized demodulation method is used as a preprocessing tool to separate signals into mono-components, so as to satisfy the requirements by energy separation algorithm. By this improvement, energy separation algorithm can be generalized to a broad range of signals, as long as the instantaneous frequency trajectories of signal components do not intersect on time-frequency plane. Due to the good adaptability of energy separation algorithm to instantaneous changes in signals and the mono-component decomposition nature of generalized demodulation, the derived time-frequency energy distribution has fine resolution and is free from cross term interferences. The good performance of the proposed time-frequency analysis is illustrated by analyses of a simulated signal and the on-site recorded nonstationary vibration signal of a hydroturbine rotor during a shut-down transient process, showing that it has potential to analyze time-varying modulated signals of multi-components.

The development of form two mathematics i-Think module (Mi-T2)

NASA Astrophysics Data System (ADS)

Yao, Foo Jing; Abdullah, Mohd Faizal Nizam Lee; Tien, Lee Tien

2017-05-01

This study aims to develop a training module i-THINK Mathematics Form Two (Mi-T2) to increase the higher-order thinking skills of students. The Mi-T2 training module was built based on the Sidek Module Development Model (2001). Constructivist learning theory, cognitive learning theory, i-THINK map and higher order thinking skills were the building blocks of the module development. In this study, researcher determined the validity and reliability of Mi-T2 module. The design being used in this study was descriptive study. To determine the needs of Mi-T2 module, questionnaires and literature review were used to collect data. When the need of the module was determined, the module was built and a pilot study was conducted to test the reliability of the Mi-T2 module. The pilot study was conducted at a secondary school in North Kinta, Perak. A Form Two class was selected to be the sample study through clustered random sampling. The pilot study was conducted for two months and one topic had been studied. The Mi-T2 module was evaluated by five expert panels to determine the content validity of the module. The instruments being used in the study were questionnaires about the necessity of the Mi-T2 module for guidance, questionnaires about the validity of the module and questionnaires concerning the reliability of the module. Statistical analysis was conducted to determine the validity and reliability coefficients of the Mi-T2 module. The content validity of Mi-T2 module was determined by Cohen's Kappa's (1968) agreement coefficient and the reliability of Mi-T2 module was determined by Cronbach Alpha's value scale. The content validity of Mi-T2 module was 0.89 and the Cronbach Alpha's value of Mi-T2 module was 0.911.

Familiarity-Based Stimulus Generalization of Conditioned Suppression

PubMed Central

2017-01-01

We report that stimulus novelty/familiarity is able to modulate stimulus generalization and discuss the theoretical implications of novelty/familiarity coding. Rats in Skinner boxes received clicker → shock pairings before generalization testing to a tone. Before clicker training, different groups of rats received preexposure treatments designed to systematically modulate the clicker and the tone’s novelty and familiarity. Rats whose preexposure matched novelty/familiarity (i.e., either both or neither clicker and tone were preexposed) showed enhanced suppression to the tone relative to rats whose preexposure mixed novelty/familiarity (i.e., only clicker or tone was preexposed). This was not the result of sensory preconditioning to clicker and tone. PMID:28383938

Physiological modules for generating discrete and rhythmic movements: action identification by a dynamic recurrent neural network.

PubMed

Bengoetxea, Ana; Leurs, Françoise; Hoellinger, Thomas; Cebolla, Ana M; Dan, Bernard; McIntyre, Joseph; Cheron, Guy

2014-01-01

In this study we employed a dynamic recurrent neural network (DRNN) in a novel fashion to reveal characteristics of control modules underlying the generation of muscle activations when drawing figures with the outstretched arm. We asked healthy human subjects to perform four different figure-eight movements in each of two workspaces (frontal plane and sagittal plane). We then trained a DRNN to predict the movement of the wrist from information in the EMG signals from seven different muscles. We trained different instances of the same network on a single movement direction, on all four movement directions in a single movement plane, or on all eight possible movement patterns and looked at the ability of the DRNN to generalize and predict movements for trials that were not included in the training set. Within a single movement plane, a DRNN trained on one movement direction was not able to predict movements of the hand for trials in the other three directions, but a DRNN trained simultaneously on all four movement directions could generalize across movement directions within the same plane. Similarly, the DRNN was able to reproduce the kinematics of the hand for both movement planes, but only if it was trained on examples performed in each one. As we will discuss, these results indicate that there are important dynamical constraints on the mapping of EMG to hand movement that depend on both the time sequence of the movement and on the anatomical constraints of the musculoskeletal system. In a second step, we injected EMG signals constructed from different synergies derived by the PCA in order to identify the mechanical significance of each of these components. From these results, one can surmise that discrete-rhythmic movements may be constructed from three different fundamental modules, one regulating the co-activation of all muscles over the time span of the movement and two others elliciting patterns of reciprocal activation operating in orthogonal directions.

Experimental Observation of a Generalized Thouless Pump with a Single Spin

NASA Astrophysics Data System (ADS)

Ma, Wenchao; Zhou, Longwen; Zhang, Qi; Li, Min; Cheng, Chunyang; Geng, Jianpei; Rong, Xing; Shi, Fazhan; Gong, Jiangbin; Du, Jiangfeng

2018-03-01

Adiabatic cyclic modulation of a one-dimensional periodic potential will result in quantized charge transport, which is termed the Thouless pump. In contrast to the original Thouless pump restricted by the topology of the energy band, here we experimentally observe a generalized Thouless pump that can be extensively and continuously controlled. The extraordinary features of the new pump originate from interband coherence in nonequilibrium initial states, and this fact indicates that a quantum superposition of different eigenstates individually undergoing quantum adiabatic following can also be an important ingredient unavailable in classical physics. The quantum simulation of this generalized Thouless pump in a two-band insulator is achieved by applying delicate control fields to a single spin in diamond. The experimental results demonstrate all principal characteristics of the generalized Thouless pump. Because the pumping in our system is most pronounced around a band-touching point, this work also suggests an alternative means to detect quantum or topological phase transitions.

Feature-specific attention allocation modulates the generalization of recently acquired likes and dislikes.

PubMed

Spruyt, Adriaan; Klauer, Karl Christoph; Gast, Anne; De Schryver, Maarten; De Houwer, Jan

2014-01-01

We examined whether the generalization of recently acquired likes and dislikes depends on feature-specific attention allocation. Likes and dislikes were established by means of an evaluative-conditioning procedure in which participants were presented with several exemplars of two subordinate categories (e.g., young men vs. old women). Whereas exemplars of one category were consistently paired with negative stimuli, exemplars of the second category were consistently paired with positive stimuli. In addition, we manipulated feature-specific attention allocation for specific stimulus dimensions (e.g., gender vs. age), either during (Experiments 1 and 2) or before the acquisition phase of the experiment (Experiment 3). Both direct and indirect attitude measures revealed a clear impact of this manipulation on attitude generalization. More specifically, only generalization stimuli that were similar to the CSs in terms of the stimulus dimension that was selectively attended to were evaluated in a manner that was congruent with the acquired liking of those CSs.

Reclamation of the wastewater from an industrial park using hollow-fibre and spiral-wound membranes: 50 m3 d(-1) pilot testing and cost evaluation.

PubMed

Chu, C P; Jiaoa, S R; Hung, J M; Lu, C J; Chung, Y J

2009-08-01

The feasibility of reclaiming effluent from industrial park wastewater treatment plants through a membrane process was evaluated in three phases. In phase 1 we selected nine wastewater treatment plants (WWTPs), each with a design capacity exceeding 10,000 m3 d(-1), and analyzed the corresponding effluent composition. 'Potential recycling percentage', R, ranged from 50% to 80% for the industrial park WWTPs, indicating a high feasibility for the reuse of effluent. In phase 2, a 50 m3 d(-1) pilot plant was installed in one of the selected WWTPs and underwent testing for one year. The quality of the reclaimed water was suitable for general-purpose industrial use. In the two ultrafiltration (UF) modules tested, the hydrophilic polyethersulfone hollow-fibre module was more tolerant to variable properties, and had higher recycling percentages than those of backwashable hydrophobic polyvinylidene difluoride spiral-wound module. Using the spiral-wound UF module helped reduce the cost for producing 1 m3 of reclaimed water (US$0.80) compared with a hollow-fibre module (US$0.88). In phase 3, we evaluated the negative effects of refluxing the reverse osmosis retentate, containing high total dissolved solids and non-biodegradable organics, with the biological treatment unit of the upstream WWTP. Biological compactibility tests showed that the refluxed retentate ratio should be reduced to maintain the conductivity of mixed liquor in the aeration tank at less than 110% of the original value.

Cardiac e-learning: Development of a web-based implantable cardioverter defibrillator educational system.

PubMed

Hickey, Kathleen T; Johnson, Mary P; Biviano, Angelo; Aboelela, Sally; Thomas, Tami; Bakken, Suzanne; Garan, Hasan; Zimmerman, John L; Whang, William

2011-04-01

The objective of this study was to design a Web-based implantable cardioverter defibrillator (ICD) module that would allow greater access to learning which could occur at an individual's convenience outside the fast-paced clinical environment. A Web-based ICD software educational program was developed to provide general knowledge of the function of the ICD and the interpretation of the stored electrocardiograms. This learning tool could be accessed at any time via the Columbia University Internet server, using a unique, password protected login. A series of basic and advanced ICD terms were presented using actual ICD screenshots and videos that simulated scenarios the practitioner would most commonly encounter in the fast-paced clinical setting. To determine the usefulness of the site and improve the module, practitioners were asked to complete a brief (less than 5 min) online survey at the end of the module. Twenty-six practitioners have logged into our Web site: 20 nurses/nurse practitioners, four cardiac fellows, and two other practitioners. The majority of respondents rated the program as easy to use and useful. The success of this module has led to it becoming part of the training for student nurse practitioners before a clinical electrophysiology rotation, and the module is accessed by our cardiac entry level fellows before a rotation in the intensive care unit or electrophysiology service. Remote electronic arrhythmia learning is a successful example of the melding of technology and education to enhance clinical learning.

Modulation of stimulus-induced 20-Hz activity for the tongue and hard palate during tongue movement in humans.

PubMed

Maezawa, Hitoshi; Onishi, Kaori; Yagyu, Kazuyori; Shiraishi, Hideaki; Hirai, Yoshiyuki; Funahashi, Makoto

2016-01-01

Modulation of 20-Hz activity in the primary sensorimotor cortex (SM1) may be important for oral functions. Here, we show that 20-Hz event-related desynchronization/synchronization (20-Hz ERD/ERS) is modulated by sensory input and motor output in the oral region. Magnetic 20-Hz activity was recorded following right-sided tongue stimulation during rest (Rest) and self-paced repetitive tongue movement (Move). To exclude proprioception effects, 20-Hz activity induced by right-sided hard palate stimulation was also recorded. The 20-Hz activity in the two conditions was compared via temporal spectral evolution analyses. 20-Hz ERD/ERS was detected over bilateral temporoparietal areas in the Rest condition for both regions. Moreover, 20-Hz ERS was significantly suppressed in the Move condition for both regions. Detection of 20-Hz ERD/ERS during the Rest condition for both regions suggests that the SM1 functional state may be modulated by oral stimulation, with or without proprioceptive effects. Moreover, the suppression of 20-Hz ERS for the hard palate during the Move condition suggests that the stimulation-induced functional state of SM1 may have been modulated by the movement, even though the movement and stimulation areas were different. Sensorimotor function of the general oral region may be finely coordinated through 20-Hz cortical oscillation. Copyright © 2015 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

Advanced Digital Signal Processing for Hybrid Lidar

DTIC Science & Technology

2014-10-30

obtain range measurements . A MATLAB- based system developed at Clarkson University in FY14 has been used to perform real-time FDR ranging... measurement accuracy. There have been various methods that attempt to reduce the backscatter. One method is to increase the modulation frequency beyond...an unambiguous range measurement . In general, it is desired to determine which combination of Radio Frequency (RF) modulation frequencies, modulation

Advanced Transport Operating System (ATOPS) utility library software description

NASA Technical Reports Server (NTRS)

Clinedinst, Winston C.; Slominski, Christopher J.; Dickson, Richard W.; Wolverton, David A.

1993-01-01

The individual software processes used in the flight computers on-board the Advanced Transport Operating System (ATOPS) aircraft have many common functional elements. A library of commonly used software modules was created for general uses among the processes. The library includes modules for mathematical computations, data formatting, system database interfacing, and condition handling. The modules available in the library and their associated calling requirements are described.

Capacity of the Generalized Pulse-Position Modulation Channel

NASA Technical Reports Server (NTRS)

Hamkins, J.; Klimesh, M.; McElience, R.; Moision, B.

2005-01-01

We show the capacity of a generalized pulse-position modulation (PPM) channel, where the input vectors may be any set that allows a transitive group of coordinate permutations, is achieved by a uniform input distribution. We derive a simple expression in terms of the Kullback Leibler distance for the binary case, and the asymptote in the PPM order. We prove a sub-additivity result for the PPM channel and use it to show PPM capacity is monotonic in the order.

Soft-Input Soft-Output Modules for the Construction and Distributed Iterative Decoding of Code Networks

NASA Technical Reports Server (NTRS)

Benedetto, S.; Divsalar, D.; Montorsi, G.; Pollara, F.

1998-01-01

Soft-input soft-output building blocks (modules) are presented to construct and iteratively decode in a distributed fashion code networks, a new concept that includes, and generalizes, various forms of concatenated coding schemes.

Effects of Context Preexposure and Delay Until Anxiety Retrieval on Generalization of Contextual Anxiety

ERIC Educational Resources Information Center

Andreatta, Marta; Neueder, Dorothea; Glotzbach-Schoon, Evelyn; Mühlberger, Andreas; Pauli, Paul

2017-01-01

Animal studies suggest that time delay between acquisition and retrieval of contextual anxiety increases generalization. Moreover, such generalization is prevented by preexposure to the context (CTX), presumably due to an improved representation of such context. We investigated whether preexposure and time-passing modulate generalization of…

Generalized Autobalanced Ramsey Spectroscopy of Clock Transitions

NASA Astrophysics Data System (ADS)

Yudin, V. I.; Taichenachev, A. V.; Basalaev, M. Yu.; Zanon-Willette, T.; Pollock, J. W.; Shuker, M.; Donley, E. A.; Kitching, J.

2018-05-01

When performing precision measurements, the quantity being measured is often perturbed by the measurement process itself. Such measurements include precision frequency measurements for atomic clock applications carried out with Ramsey spectroscopy. With the aim of eliminating probe-induced perturbations, a method of generalized autobalanced Ramsey spectroscopy (GABRS) is presented and rigorously substantiated. The usual local-oscillator frequency control loop is augmented with a second control loop derived from secondary Ramsey sequences interspersed with the primary sequences and with a different Ramsey period. This second loop feeds back to a secondary clock variable and ultimately compensates for the perturbation of the clock frequency caused by the measurements in the first loop. We show that such a two-loop scheme can lead to perfect compensation for measurement-induced light shifts and does not suffer from the effects of relaxation, time-dependent pulse fluctuations and phase-jump modulation errors that are typical of other hyper-Ramsey schemes. Several variants of GABRS are explored based on different secondary variables including added relative phase shifts between Ramsey pulses, external frequency-step compensation, and variable second-pulse duration. We demonstrate that a universal antisymmetric error signal, and hence perfect compensation at a finite modulation amplitude, is generated only if an additional frequency step applied during both Ramsey pulses is used as the concomitant variable parameter. This universal technique can be applied to the fields of atomic clocks, high-resolution molecular spectroscopy, magnetically induced and two-photon probing schemes, Ramsey-type mass spectrometry, and the field of precision measurements. Some variants of GABRS can also be applied for rf atomic clocks using coherent-population-trapping-based Ramsey spectroscopy of the two-photon dark resonance.

Is My Network Module Preserved and Reproducible?

PubMed Central

Langfelder, Peter; Luo, Rui; Oldham, Michael C.; Horvath, Steve

2011-01-01

In many applications, one is interested in determining which of the properties of a network module change across conditions. For example, to validate the existence of a module, it is desirable to show that it is reproducible (or preserved) in an independent test network. Here we study several types of network preservation statistics that do not require a module assignment in the test network. We distinguish network preservation statistics by the type of the underlying network. Some preservation statistics are defined for a general network (defined by an adjacency matrix) while others are only defined for a correlation network (constructed on the basis of pairwise correlations between numeric variables). Our applications show that the correlation structure facilitates the definition of particularly powerful module preservation statistics. We illustrate that evaluating module preservation is in general different from evaluating cluster preservation. We find that it is advantageous to aggregate multiple preservation statistics into summary preservation statistics. We illustrate the use of these methods in six gene co-expression network applications including 1) preservation of cholesterol biosynthesis pathway in mouse tissues, 2) comparison of human and chimpanzee brain networks, 3) preservation of selected KEGG pathways between human and chimpanzee brain networks, 4) sex differences in human cortical networks, 5) sex differences in mouse liver networks. While we find no evidence for sex specific modules in human cortical networks, we find that several human cortical modules are less preserved in chimpanzees. In particular, apoptosis genes are differentially co-expressed between humans and chimpanzees. Our simulation studies and applications show that module preservation statistics are useful for studying differences between the modular structure of networks. Data, R software and accompanying tutorials can be downloaded from the following webpage: http://www.genetics.ucla.edu/labs/horvath/CoexpressionNetwork/ModulePreservation. PMID:21283776

Physiological modules for generating discrete and rhythmic movements: component analysis of EMG signals.

PubMed

Bengoetxea, Ana; Leurs, Françoise; Hoellinger, Thomas; Cebolla, Ana Maria; Dan, Bernard; Cheron, Guy; McIntyre, Joseph

2014-01-01

A central question in Neuroscience is that of how the nervous system generates the spatiotemporal commands needed to realize complex gestures, such as handwriting. A key postulate is that the central nervous system (CNS) builds up complex movements from a set of simpler motor primitives or control modules. In this study we examined the control modules underlying the generation of muscle activations when performing different types of movement: discrete, point-to-point movements in eight different directions and continuous figure-eight movements in both the normal, upright orientation and rotated 90°. To test for the effects of biomechanical constraints, movements were performed in the frontal-parallel or sagittal planes, corresponding to two different nominal flexion/abduction postures of the shoulder. In all cases we measured limb kinematics and surface electromyographic activity (EMG) signals for seven different muscles acting around the shoulder. We first performed principal component analysis (PCA) of the EMG signals on a movement-by-movement basis. We found a surprisingly consistent pattern of muscle groupings across movement types and movement planes, although we could detect systematic differences between the PCs derived from movements performed in each shoulder posture and between the principal components associated with the different orientations of the figure. Unexpectedly we found no systematic differences between the figure eights and the point-to-point movements. The first three principal components could be associated with a general co-contraction of all seven muscles plus two patterns of reciprocal activation. From these results, we surmise that both "discrete-rhythmic movements" such as the figure eight, and discrete point-to-point movement may be constructed from three different fundamental modules, one regulating the impedance of the limb over the time span of the movement and two others operating to generate movement, one aligned with the vertical and the other aligned with the horizontal.

Physiological modules for generating discrete and rhythmic movements: component analysis of EMG signals

PubMed Central

Bengoetxea, Ana; Leurs, Françoise; Hoellinger, Thomas; Cebolla, Ana Maria; Dan, Bernard; Cheron, Guy; McIntyre, Joseph

2015-01-01

A central question in Neuroscience is that of how the nervous system generates the spatiotemporal commands needed to realize complex gestures, such as handwriting. A key postulate is that the central nervous system (CNS) builds up complex movements from a set of simpler motor primitives or control modules. In this study we examined the control modules underlying the generation of muscle activations when performing different types of movement: discrete, point-to-point movements in eight different directions and continuous figure-eight movements in both the normal, upright orientation and rotated 90°. To test for the effects of biomechanical constraints, movements were performed in the frontal-parallel or sagittal planes, corresponding to two different nominal flexion/abduction postures of the shoulder. In all cases we measured limb kinematics and surface electromyographic activity (EMG) signals for seven different muscles acting around the shoulder. We first performed principal component analysis (PCA) of the EMG signals on a movement-by-movement basis. We found a surprisingly consistent pattern of muscle groupings across movement types and movement planes, although we could detect systematic differences between the PCs derived from movements performed in each shoulder posture and between the principal components associated with the different orientations of the figure. Unexpectedly we found no systematic differences between the figure eights and the point-to-point movements. The first three principal components could be associated with a general co-contraction of all seven muscles plus two patterns of reciprocal activation. From these results, we surmise that both “discrete-rhythmic movements” such as the figure eight, and discrete point-to-point movement may be constructed from three different fundamental modules, one regulating the impedance of the limb over the time span of the movement and two others operating to generate movement, one aligned with the vertical and the other aligned with the horizontal. PMID:25620928

Effects on interaction kinetics of mutations at the VH-VL interface of Fabs depend on the structural context.

PubMed

Khalifa, M B; Weidenhaupt, M; Choulier, L; Chatellier, J; Rauffer-Bruyère, N; Altschuh, D; Vernet, T

2000-01-01

The influence of framework residues belonging to VH and VL modules of antibody molecules on antigen binding remains poorly understood. To investigate the functional role of such residues, we have performed semi-conservative amino acid replacements at the VH-VL interface. This work was carried out with (i) variants of the same antibody and (ii) with antibodies of different specificities (Fab fragments 145P and 1F1h), in order to check if functional effects are additive and/or similar for the two antibodies. Interaction kinetics of Fab mutants with peptide and protein antigens were measured using a BIACORE instrument. The substitutions introduced at the VH-VL interface had no significant effects on k(a) but showed small, significant effects on k(d). Mutations in the VH module affected k(d) not only for the two different antibodies but also for variants of the same antibody. These effects varied both in direction and in magnitude. In the VL module, the double mutation F(L37)L-Q(L38)L, alone or in combination with other mutations, consistently decreased k(d) about two-fold in Fab 145P. Other mutations in the VL module had no effect on k(d) in 145P, but always decreased k(d) in 1F1h. Moreover, in both systems, small-magnitude non-additive effects on k(d) were observed, but affinity variations seemed to be limited by a threshold. When comparing functional effects in antibodies of different specificity, no general rules could be established. In addition, no clear relationship could be pointed out between the nature of the amino acid change and the observed functional effect. Our results show that binding kinetics are affected by alteration of framework residues remote from the binding site, although these effects are unpredictable for most of the studied changes. Copyright 2000 John Wiley & Sons, Ltd.

Spectro-temporal modulation masking patterns reveal frequency selectivity.

PubMed

Oetjen, Arne; Verhey, Jesko L

2015-02-01

The present study investigated the possibility that the human auditory system demonstrates frequency selectivity to spectro-temporal amplitude modulations. Threshold modulation depth for detecting sinusoidal spectro-temporal modulations was measured using a generalized masked threshold pattern paradigm with narrowband masker modulations. Four target spectro-temporal modulations were examined, differing in their temporal and spectral modulation frequencies: a temporal modulation of -8, 8, or 16 Hz combined with a spectral modulation of 1 cycle/octave and a temporal modulation of 4 Hz combined with a spectral modulation of 0.5 cycles/octave. The temporal center frequencies of the masker modulation ranged from 0.25 to 4 times the target temporal modulation. The spectral masker-modulation center-frequencies were 0, 0.5, 1, 1.5, and 2 times the target spectral modulation. For all target modulations, the pattern of average thresholds for the eight normal-hearing listeners was consistent with the hypothesis of a spectro-temporal modulation filter. Such a pattern of modulation-frequency sensitivity was predicted on the basis of psychoacoustical data for purely temporal amplitude modulations and purely spectral amplitude modulations. An analysis of separability indicates that, for the present data set, selectivity in the spectro-temporal modulation domain can be described by a combination of a purely spectral and a purely temporal modulation filter function.

Computational wavelength resolution for in-line lensless holography: phase-coded diffraction patterns and wavefront group-sparsity

NASA Astrophysics Data System (ADS)

Katkovnik, Vladimir; Shevkunov, Igor; Petrov, Nikolay V.; Egiazarian, Karen

2017-06-01

In-line lensless holography is considered with a random phase modulation at the object plane. The forward wavefront propagation is modelled using the Fourier transform with the angular spectrum transfer function. The multiple intensities (holograms) recorded by the sensor are random due to the random phase modulation and noisy with Poissonian noise distribution. It is shown by computational experiments that high-accuracy reconstructions can be achieved with resolution going up to the two thirds of the wavelength. With respect to the sensor pixel size it is a super-resolution with a factor of 32. The algorithm designed for optimal superresolution phase/amplitude reconstruction from Poissonian data is based on the general methodology developed for phase retrieval with a pixel-wise resolution in V. Katkovnik, "Phase retrieval from noisy data based on sparse approximation of object phase and amplitude", http://www.cs.tut.fi/ lasip/DDT/index3.html.

Phase Two of the Array Automated Assembly Task for the Low Cost Solar Array Project

NASA Technical Reports Server (NTRS)

Campbell, R. B.; Page, D. J.; Rai-Choudhury, P.; Seman, E. J.; Hanes, M. H.; Rohatgi, A.; Davis, J. R.

1979-01-01

Various top contact metal systems were studied. Only Ti Pd Cu approaches baseline (Ti Pd Ag) quality, but this system shows a lack of long term stability. Aluminum back surface field structures were fabricated and thicknesses of p superscript + material of up to 7.0 microns were achieved with open circuit voltages of 0.59V. A general purpose ultrasonic welder was purchased and tests using various metal foils are under way. During fabrication of the demonstration module, several cells became cracked. Due to redundancy of interconnections, the module was not open circuited but the efficiency was reduced to 8.8%. The broken cell was interconnected with a strap across the back and the efficiency was increased to 11.5%. A cost analysis was made and the results indicate a selling price of $0.56/watt peak (in 1986 with 1975 dollars).

A new (2+1) dimensional integrable evolution equation for an ion acoustic wave in a magnetized plasma

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

Mukherjee, Abhik, E-mail: abhik.mukherjee@saha.ac.in; Janaki, M. S., E-mail: ms.janaki@saha.ac.in; Kundu, Anjan, E-mail: anjan.kundu@saha.ac.in

2015-07-15

A new, completely integrable, two dimensional evolution equation is derived for an ion acoustic wave propagating in a magnetized, collisionless plasma. The equation is a multidimensional generalization of a modulated wavepacket with weak transverse propagation, which has resemblance to nonlinear Schrödinger (NLS) equation and has a connection to Kadomtsev-Petviashvili equation through a constraint relation. Higher soliton solutions of the equation are derived through Hirota bilinearization procedure, and an exact lump solution is calculated exhibiting 2D structure. Some mathematical properties demonstrating the completely integrable nature of this equation are described. Modulational instability using nonlinear frequency correction is derived, and the correspondingmore » growth rate is calculated, which shows the directional asymmetry of the system. The discovery of this novel (2+1) dimensional integrable NLS type equation for a magnetized plasma should pave a new direction of research in the field.« less

Eliminating degradation and uncovering ion-trapping dynamics in electrochromic WO3 thin films

PubMed Central

Wen, Rui-Tao; Granqvist, Claes G.; Niklasson, Gunnar A.

2015-01-01

Amorphous WO3 thin films are of keen interest as cathodic electrodes in transmittance-modulating electrochromic devices. However, these films suffer from ion-trapping-induced degradation of optical modulation and reversibility upon extended Li+-ion exchange. Here, we demonstrate that ion-trapping-induced degradation, which is commonly believed to be irreversible, can be successfully eliminated by constant-current-driven de-trapping, i.e., WO3 films can be rejuvenated and regain their initial highly reversible electrochromic performance. Pronounced ion-trapping occurs when x exceeds ~0.65 in LixWO3 during ion insertion. We find two main kinds of Li+-ion trapping sites (intermediate and deep) in WO3, where the intermediate ones are most prevalent. Li+-ions can be completely removed from intermediate traps but are irreversibly bound in deep traps. Our results provide a general framework for developing and designing superior electrochromic materials and devices. PMID:26259104

Electron cryo-microscopy structure of the canonical TRPC4 ion channel

PubMed Central

Vinayagam, Deivanayagabarathy; Mager, Thomas; Apelbaum, Amir; Bothe, Arne; Merino, Felipe; Hofnagel, Oliver; Gatsogiannis, Christos

2018-01-01

Canonical transient receptor channels (TRPC) are non-selective cation channels. They are involved in receptor-operated Ca2+ signaling and have been proposed to act as store-operated channels (SOC). Their malfunction is related to cardiomyopathies and their modulation by small molecules has been shown to be effective against renal cancer cells. The molecular mechanism underlying the complex activation and regulation is poorly understood. Here, we report the electron cryo-microscopy structure of zebrafish TRPC4 in its unliganded (apo), closed state at an overall resolution of 3.6 Å. The structure reveals the molecular architecture of the cation conducting pore, including the selectivity filter and lower gate. The cytoplasmic domain contains two key hubs that have been shown to interact with modulating proteins. Structural comparisons with other TRP channels give novel insights into the general architecture and domain organization of this superfamily of channels and help to understand their function and pharmacology. PMID:29717981

Catecholaminergic challenge uncovers distinct Pavlovian and instrumental mechanisms of motivated (in)action.

PubMed

Swart, Jennifer C; Froböse, Monja I; Cook, Jennifer L; Geurts, Dirk Em; Frank, Michael J; Cools, Roshan; den Ouden, Hanneke Em

2017-05-15

Catecholamines modulate the impact of motivational cues on action. Such motivational biases have been proposed to reflect cue-based, 'Pavlovian' effects. Here, we assess whether motivational biases may also arise from asymmetrical instrumental learning of active and passive responses following reward and punishment outcomes. We present a novel paradigm, allowing us to disentangle the impact of reward and punishment on instrumental learning from Pavlovian response biasing. Computational analyses showed that motivational biases reflect both Pavlovian and instrumental effects: reward and punishment cues promoted generalized (in)action in a Pavlovian manner, whereas outcomes enhanced instrumental (un)learning of chosen actions. These cue- and outcome-based biases were altered independently by the catecholamine enhancer melthylphenidate. Methylphenidate's effect varied across individuals with a putative proxy of baseline dopamine synthesis capacity, working memory span. Our study uncovers two distinct mechanisms by which motivation impacts behaviour, and helps refine current models of catecholaminergic modulation of motivated action.

The prelimbic cortex uses higher-order cues to modulate both the acquisition and expression of conditioned fear

PubMed Central

Sharpe, Melissa J.; Killcross, Simon

2015-01-01

The prelimbic (PL) cortex allows rodents to adapt their responding under changing experimental circumstances. In line with this, the PL cortex has been implicated in strategy set shifting, attentional set shifting, the resolution of response conflict, and the modulation of attention towards predictive stimuli. One interpretation of this research is that the PL cortex is involved in using information garnered from higher-order cues in the environment to modulate how an animal responds to environmental stimuli. However, data supporting this view of PL function in the aversive domain are lacking. In the following experiments, we attempted to answer two questions. Firstly, we wanted to investigate whether the role of the PL cortex in using higher-order cues to influence responding generalizes across appetitive and aversive domains. Secondly, as much of the research has focused on a role for the PL cortex in performance, we wanted to assess whether this region is also involved in the acquisition of hierarchal associations which facilitate an ability to use higher-order cues to modulate responding. In order to answer these questions, we assessed the impact of PL inactivation during both the acquisition and expression of a contextual bi-conditional discrimination. A contextual bi-conditional discrimination involves presenting two stimuli. In one context, one stimulus is paired with shock while the other is presented without shock. In another context, these contingencies are reversed. Thus, animals have to use the present contextual cues to disambiguate the significance of the stimulus and respond appropriately. We found that PL inactivation disrupted both the encoding and expression of these context-dependent associations. This supports a role for the PL cortex in allowing higher-order cues to modulate both learning about, and responding towards, different cues. We discuss these findings in the broader context of functioning in the medial prefrontal cortex (PFC). PMID:25628542