Techniques for estimating Space Station aerodynamic characteristics
NASA Technical Reports Server (NTRS)
Thomas, Richard E.
1993-01-01
A method was devised and calculations were performed to determine the effects of reflected molecules on the aerodynamic force and moment coefficients for a body in free molecule flow. A procedure was developed for determining the velocity and temperature distributions of molecules reflected from a surface of arbitrary momentum and energy accommodation. A system of equations, based on momentum and energy balances for the surface, incident, and reflected molecules, was solved by a numerical optimization technique. The minimization of a 'cost' function, developed from the set of equations, resulted in the determination of the defining properties of the flow reflected from the arbitrary surface. The properties used to define both the incident and reflected flows were: average temperature of the molecules in the flow, angle of the flow with respect to a vector normal to the surface, and the molecular speed ratio. The properties of the reflected flow were used to calculate the contribution of multiply reflected molecules to the force and moments on a test body in the flow. The test configuration consisted of two flat plates joined along one edge at a right angle to each other. When force and moment coefficients of this 90 deg concave wedge were compared to results that did not include multiple reflections, it was found that multiple reflections could nearly double lift and drag coefficients, with nearly a 50 percent increase in pitching moment for cases with specular or nearly specular accommodation. The cases of diffuse or nearly diffuse accommodation often had minor reductions in axial and normal forces when multiple reflections were included. There were several cases of intermediate accommodation where the addition of multiple reflection effects more than tripled the lift coefficient over the convex technique.
Multiple-channel, total-reflection optic with controllable divergence
Gibson, David M.; Downing, Robert G.
1997-01-01
An apparatus and method for providing focused x-ray, gamma-ray, charged particle and neutral particle, including neutron, radiation beams with a controllable amount of divergence are disclosed. The apparatus features a novel use of a radiation blocking structure, which, when combined with multiple-channel total reflection optics, increases the versatility of the optics by providing user-controlled output-beam divergence.
Multiple-channel, total-reflection optic with controllable divergence
Gibson, D.M.; Downing, R.G.
1997-02-18
An apparatus and method for providing focused x-ray, gamma-ray, charged particle and neutral particle, including neutron, radiation beams with a controllable amount of divergence are disclosed. The apparatus features a novel use of a radiation blocking structure, which, when combined with multiple-channel total reflection optics, increases the versatility of the optics by providing user-controlled output-beam divergence. 11 figs.
On the Angular Variation of Solar Reflectance of Snow
NASA Technical Reports Server (NTRS)
Chang, A. T. C.; Choudhury, B. J.
1979-01-01
Spectral and integrated solar reflectance of nonhomogeneous snowpacks were derived assuming surface reflection of direct radiation and subsurface multiple scattering. For surface reflection, a bidirectional reflectance distribution function derived for an isotropic Gaussian faceted surface was considered and for subsurface multiple scattering, an approximate solution of the radiative transfer equation was studied. Solar radiation incident on the snowpack was decomposed into direct and atmospherically scattered radiation. Spectral attenuation coefficients of ozone, carbon dioxide, water vapor, aerosol and molecular scattering were included in the calculation of incident solar radiation. Illustrative numerical results were given for a case of North American winter atmospheric conditions. The calculated dependence of spectrally integrated directional reflectance (or albedo) on solar elevation was in qualitative agreement with available observations.
Seismic reflection imaging, accounting for primary and multiple reflections
NASA Astrophysics Data System (ADS)
Wapenaar, Kees; van der Neut, Joost; Thorbecke, Jan; Broggini, Filippo; Slob, Evert; Snieder, Roel
2015-04-01
Imaging of seismic reflection data is usually based on the assumption that the seismic response consists of primary reflections only. Multiple reflections, i.e. waves that have reflected more than once, are treated as primaries and are imaged at wrong positions. There are two classes of multiple reflections, which we will call surface-related multiples and internal multiples. Surface-related multiples are those multiples that contain at least one reflection at the earth's surface, whereas internal multiples consist of waves that have reflected only at subsurface interfaces. Surface-related multiples are the strongest, but also relatively easy to deal with because the reflecting boundary (the earth's surface) is known. Internal multiples constitute a much more difficult problem for seismic imaging, because the positions and properties of the reflecting interfaces are not known. We are developing reflection imaging methodology which deals with internal multiples. Starting with the Marchenko equation for 1D inverse scattering problems, we derived 3D Marchenko-type equations, which relate reflection data at the surface to Green's functions between virtual sources anywhere in the subsurface and receivers at the surface. Based on these equations, we derived an iterative scheme by which these Green's functions can be retrieved from the reflection data at the surface. This iterative scheme requires an estimate of the direct wave of the Green's functions in a background medium. Note that this is precisely the same information that is also required by standard reflection imaging schemes. However, unlike in standard imaging, our iterative Marchenko scheme retrieves the multiple reflections of the Green's functions from the reflection data at the surface. For this, no knowledge of the positions and properties of the reflecting interfaces is required. Once the full Green's functions are retrieved, reflection imaging can be carried out by which the primaries and multiples are mapped to their correct positions, with correct reflection amplitudes. In the presentation we will illustrate this new methodology with numerical examples and discuss its potential and limitations.
NASA Astrophysics Data System (ADS)
Kobayashi, Satoru; Tanelli, Simone; Im, Eastwood
2005-12-01
Effects of multiple scattering on reflectivity are studied for millimeter wavelength weather radars. A time-independent vector theory, including up to second-order scattering, is derived for a single layer of hydrometeors of a uniform density and a uniform diameter. In this theory, spherical waves with a Gaussian antenna pattern are used to calculate ladder and cross terms in the analytical scattering theory. The former terms represent the conventional multiple scattering, while the latter terms cause backscattering enhancement in both the copolarized and cross-polarized components. As the optical thickness of the hydrometeor layer increases, the differences from the conventional plane wave theory become more significant, and essentially, the reflectivity of multiple scattering depends on the ratio of mean free path to radar footprint radius. These results must be taken into account when analyzing radar reflectivity for use in remote sensing.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Erlangga, Mokhammad Puput
Separation between signal and noise, incoherent or coherent, is important in seismic data processing. Although we have processed the seismic data, the coherent noise is still mixing with the primary signal. Multiple reflections are a kind of coherent noise. In this research, we processed seismic data to attenuate multiple reflections in the both synthetic and real seismic data of Mentawai. There are several methods to attenuate multiple reflection, one of them is Radon filter method that discriminates between primary reflection and multiple reflection in the τ-p domain based on move out difference between primary reflection and multiple reflection. However, inmore » case where the move out difference is too small, the Radon filter method is not enough to attenuate the multiple reflections. The Radon filter also produces the artifacts on the gathers data. Except the Radon filter method, we also use the Wave Equation Multiple Elimination (WEMR) method to attenuate the long period multiple reflection. The WEMR method can attenuate the long period multiple reflection based on wave equation inversion. Refer to the inversion of wave equation and the magnitude of the seismic wave amplitude that observed on the free surface, we get the water bottom reflectivity which is used to eliminate the multiple reflections. The WEMR method does not depend on the move out difference to attenuate the long period multiple reflection. Therefore, the WEMR method can be applied to the seismic data which has small move out difference as the Mentawai seismic data. The small move out difference on the Mentawai seismic data is caused by the restrictiveness of far offset, which is only 705 meter. We compared the real free multiple stacking data after processing with Radon filter and WEMR process. The conclusion is the WEMR method can more attenuate the long period multiple reflection than the Radon filter method on the real (Mentawai) seismic data.« less
Performance analysis of cross-seeding WDM-PON system using transfer matrix method
NASA Astrophysics Data System (ADS)
Simatupang, Joni Welman; Pukhrambam, Puspa Devi; Huang, Yen-Ru
2016-12-01
In this paper, a model based on the transfer matrix method is adopted to analyze the effects of Rayleigh backscattering and Fresnel multiple reflections on a cross-seeding WDM-PON system. As part of analytical approximation methods, this time-independent model is quite simple but very efficient when it is applied to various WDM-PON transmission systems, including the cross-seeding scheme. The cross seeding scheme is most beneficial for systems with low loop-back ONU gain or low reflection loss at the drop fiber for upstream data in bidirectional transmission. However for downstream data transmission, multiple reflections power could destroy the usefulness of the cross-seeding scheme when the reflectivity is high enough and the RN is positioned near OLT or close to ONU.
Thilak, Vimal; Voelz, David G; Creusere, Charles D
2007-10-20
A passive-polarization-based imaging system records the polarization state of light reflected by objects that are illuminated with an unpolarized and generally uncontrolled source. Such systems can be useful in many remote sensing applications including target detection, object segmentation, and material classification. We present a method to jointly estimate the complex index of refraction and the reflection angle (reflected zenith angle) of a target from multiple measurements collected by a passive polarimeter. An expression for the degree of polarization is derived from the microfacet polarimetric bidirectional reflectance model for the case of scattering in the plane of incidence. Using this expression, we develop a nonlinear least-squares estimation algorithm for extracting an apparent index of refraction and the reflection angle from a set of polarization measurements collected from multiple source positions. Computer simulation results show that the estimation accuracy generally improves with an increasing number of source position measurements. Laboratory results indicate that the proposed method is effective for recovering the reflection angle and that the estimated index of refraction provides a feature vector that is robust to the reflection angle.
NASA Astrophysics Data System (ADS)
Thilak, Vimal; Voelz, David G.; Creusere, Charles D.
2007-10-01
A passive-polarization-based imaging system records the polarization state of light reflected by objects that are illuminated with an unpolarized and generally uncontrolled source. Such systems can be useful in many remote sensing applications including target detection, object segmentation, and material classification. We present a method to jointly estimate the complex index of refraction and the reflection angle (reflected zenith angle) of a target from multiple measurements collected by a passive polarimeter. An expression for the degree of polarization is derived from the microfacet polarimetric bidirectional reflectance model for the case of scattering in the plane of incidence. Using this expression, we develop a nonlinear least-squares estimation algorithm for extracting an apparent index of refraction and the reflection angle from a set of polarization measurements collected from multiple source positions. Computer simulation results show that the estimation accuracy generally improves with an increasing number of source position measurements. Laboratory results indicate that the proposed method is effective for recovering the reflection angle and that the estimated index of refraction provides a feature vector that is robust to the reflection angle.
Specimen illumination apparatus with optical cavity for dark field illumination
Pinkel, Daniel; Sudar, Damir; Albertson, Donna
1999-01-01
An illumination apparatus with a specimen slide holder, an illumination source, an optical cavity producing multiple reflection of illumination light to a specimen comprising a first and a second reflective surface arranged to achieve multiple reflections of light to a specimen is provided. The apparatus can further include additional reflective surfaces to achieve the optical cavity, a slide for mounting the specimen, a coverslip which is a reflective component of the optical cavity, one or more prisms for directing light within the optical cavity, antifading solutions for improving the viewing properties of the specimen, an array of materials for analysis, fluorescent components, curved reflective surfaces as components of the optical cavity, specimen detection apparatus, optical detection equipment, computers for analysis of optical images, a plane polarizer, fiberoptics, light transmission apertures, microscopic components, lenses for viewing the specimen, and upper and lower mirrors above and below the specimen slide as components of the optical cavity. Methods of using the apparatus are also provided.
An Examination of the Addition of Video Informed Reflective Practice to the Active Support Toolkit
ERIC Educational Resources Information Center
Baker, Peter; Appleton, Philippa; Williams, Rosie
2017-01-01
Background: This study evaluated a package of Active Support (AS), which included standard training with additional video informed reflective practice. Materials & Methods: The training package was implemented as part of a service improvement initiative in four residential intellectual disability homes, using a concurrent multiple baseline…
High power water load for microwave and millimeter-wave radio frequency sources
Ives, R. Lawrence; Mizuhara, Yosuke M.; Schumacher, Richard V.; Pendleton, Rand P.
1999-01-01
A high power water load for microwave and millimeter wave radio frequency sources has a front wall including an input port for the application of RF power, a cylindrical dissipation cavity lined with a dissipating material having a thickness which varies with depth, and a rear wall including a rotating reflector for the reflection of wave energy inside the cylindrical cavity. The dissipation cavity includes a water jacket for removal of heat generated by the absorptive material coating the dissipation cavity, and this absorptive material has a thickness which is greater near the front wall than near the rear wall. Waves entering the cavity reflect from the rotating reflector, impinging and reflecting multiple times on the absorptive coating of the dissipation cavity, dissipating equal amounts of power on each internal reflection.
NASA Astrophysics Data System (ADS)
Miyachi, Yukiya; Arakawa, Mototaka; Kanai, Hiroshi
2018-07-01
In our studies on ultrasonic elasticity assessment, minute change in the thickness of the arterial wall was measured by the phased-tracking method. However, most images in carotid artery examinations contain multiple-reflection noise, making it difficult to evaluate arterial wall elasticity precisely. In the present study, a modified phased-tracking method using the pulse inversion method was examined to reduce the influence of the multiple-reflection noise. Moreover, aliasing in the harmonic components was corrected by the fundamental components. The conventional and proposed methods were applied to a pulsated tube phantom mimicking the arterial wall. For the conventional method, the elasticity was 298 kPa without multiple-reflection noise and 353 kPa with multiple-reflection noise on the posterior wall. That of the proposed method was 302 kPa without multiple-reflection noise and 297 kPa with multiple-reflection noise on the posterior wall. Therefore, the proposed method was very robust against multiple-reflection noise.
Melanin and blood concentration in human skin studied by multiple regression analysis: experiments
NASA Astrophysics Data System (ADS)
Shimada, M.; Yamada, Y.; Itoh, M.; Yatagai, T.
2001-09-01
Knowledge of the mechanism of human skin colour and measurement of melanin and blood concentration in human skin are needed in the medical and cosmetic fields. The absorbance spectrum from reflectance at the visible wavelength of human skin increases under several conditions such as a sunburn or scalding. The change of the absorbance spectrum from reflectance including the scattering effect does not correspond to the molar absorption spectrum of melanin and blood. The modified Beer-Lambert law is applied to the change in the absorbance spectrum from reflectance of human skin as the change in melanin and blood is assumed to be small. The concentration of melanin and blood was estimated from the absorbance spectrum reflectance of human skin using multiple regression analysis. Estimated concentrations were compared with the measured one in a phantom experiment and this method was applied to in vivo skin.
A Study of Two English Language Coursebooks in Turkey: Focus on Multiple Intelligences
ERIC Educational Resources Information Center
Arikan, Arda; Soydan, Elif; Isler, Özlem
2014-01-01
This study aims to analyze two coursebooks, namely, "Texture of English 4" and "My English 5" on the basis of to what extent the activities and tasks included reflect the intelligent types proposed by multiple intelligences theory. Taking the general characteristics of the intelligences into account, a checklist has been…
Control of Visually Guided Saccades in Multiple Sclerosis: Disruption to Higher-Order Processes
ERIC Educational Resources Information Center
Fielding, Joanne; Kilpatrick, Trevor; Millist, Lynette; White, Owen
2009-01-01
Ocular motor abnormalities are a common feature of multiple sclerosis (MS), with more salient deficits reflecting tissue damage within brainstem and cerebellar circuits. However, MS may also result in disruption to higher level or cognitive control processes governing eye movement, including attentional processes that enhance the neural processing…
In-flight radiometric calibration of the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS)
NASA Technical Reports Server (NTRS)
Conel, James E.; Green, Robert O.; Alley, Ronald E.; Bruegge, Carol J.; Carrere, Veronique; Margolis, Jack S.; Vane, Gregg; Chrien, Thomas G.; Slater, Philip N.; Biggard, Stuart F.
1988-01-01
A reflectance-based method was used to provide an analysis of the in-flight radiometric performance of AVIRIS. Field spectral reflectance measurements of the surface and extinction measurements of the atmosphere using solar radiation were used as input to atmospheric radiative transfer calculations. Five separate codes were used in the analysis. Four include multiple scattering, and the computed radiances from these for flight conditions were in good agreement. Code-generated radiances were compared with AVIRIS-predicted radiances based on two laboratory calibrations (pre- and post-season of flight) for a uniform highly reflecting natural dry lake target. For one spectrometer (C), the pre- and post-season calibration factors were found to give identical results, and to be in agreement with the atmospheric models that include multiple scattering. This positive result validates the field and laboratory calibration technique. Results for the other spectrometers (A, B and D) were widely at variance with the models no matter which calibration factors were used. Potential causes of these discrepancies are discussed.
Universal Algorithms for Plant Phenotyping: Are we there yet?
NASA Astrophysics Data System (ADS)
Kakani, V. G.; Kambham, R. R.; Zhao, D.; Foster, A. J.; Gowda, P. H.
2017-12-01
Hyperspectral remote sensing offers ability to capture spectral signatures of plant morpho-physio-biochemical traits at multiple scales (leaf to canopy to aerial). Experimental results on plant phenotype from pot, growth chamber and field studies at multiple location were used in this study. Pigment, leaf/plant water status, plant nutrient status, plant height, leaf area, fresh and dry weights of biomass and its components are correlated with hyperspectral reflectance signatures. Leaf reflectance was collected with spectroradiometer having a light source. Canopy hyperspectral reflectance was collected from 1.5 m above the canopy using a spectroradiometer, while multispectral images were acquired from aerial platforms ( 400m). Several statistical methods including simple ratios, principal component analysis, and partial least squares regression were used to identify hyperspectral reflectance bands that were tightly associated with plant phenotypic traits. Leaf level spectra best described the morpho-physio-biochemical traits (R2 = 0.6-0.9), while canopy reflectance best described plant height (R2 = 0.65), leaf area index (R2 = 0.67-0.74) and biomass (R2 = 0.69-0.78), while aerial spectra improved canopy level regression coefficients for plant height (R2 = 0.93) and leaf area index (R2 = 0.89). The comparison of multi-level spectra and resolution, clearly showed the advantage of hyperspectral reflectance data over the multispectral reflectance data, particularly for understanding the basis for spectral reflectance differences among species and traits. In conclusion, high resolution (1-2 cm) spectral imagery can help to bridge the gap across multiple levels of phenotype measurement.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zakgeim, A. L.; Il’inskaya, N. D.; Karandashev, S. A.
2017-02-15
The spatial distribution of equilibrium and nonequilibrium (including luminescent) IR (infrared) radiation in flip-chip photodiodes based on InAsSbP/InAs double heterostructures (λ{sub max} = 3.4 μm) is measured and analyzed; the structural features of the photodiodes, including the reflective properties of the ohmic contacts, are taken into account. Optical area enhancement due to multiple internal reflection in photodiodes with different geometric characteristics is estimated.
NASA Technical Reports Server (NTRS)
Khazanov, George V.; Himwich, Elizabeth W.; Glocer, Alex; Sibeck, David G.
2015-01-01
The precipitation of high-energy magnetospheric electrons (E greater than 500-600 electronvolts) in the diffuse aurora contributes significant energy flux into Earth's ionosphere. In the diffuse aurora, precipitating electrons initially injected from the plasmasheet via wave-particle interaction processes degrade in the atmosphere toward lower energies and produce secondary electrons via impact ionization of the neutral atmosphere. These initially precipitating electrons of magnetospheric origin can be additionally reflected back into the magnetosphere by the two magnetically conjugated atmospheres, leading to a series of multiple reflections that can greatly influence the initially precipitating flux at the upper ionospheric boundary (700-800 kilometers) and the resultant population of secondary electrons and electrons cascading toward lower energies. We present the solution of the Boltzmann.Landau kinetic equation that uniformly describes the entire electron distribution function in the diffuse aurora, including the affiliated production of secondary electrons (E is less than or equal to 600 electronvolts) and their energy interplay in the magnetosphere and two conjugated ionospheres. This solution takes into account the role of multiple atmospheric reflections of the precipitated electrons that were initially moved into the loss cone via wave.particle interaction processes in Earth's plasmasheet.
Ferris, Rosie; Blaum, Caroline; Kiwak, Eliza; Austin, Janet; Esterson, Jessica; Harkless, Gene; Oftedahl, Gary; Parchman, Michael; Van Ness, Peter H; Tinetti, Mary E
2018-06-01
To ascertain perspectives of multiple stakeholders on contributors to inappropriate care for older adults with multiple chronic conditions. Perspectives of 36 purposively sampled patients, clinicians, health systems, and payers were elicited. Data analysis followed a constant comparative method. Structural factors triggering burden and fragmentation include disease-based quality metrics and need to interact with multiple clinicians. The key cultural barrier identified is the assumption that "physicians know best." Inappropriate decision making may result from inattention to trade-offs and adherence to multiple disease guidelines. Stakeholders recommended changes in culture, structure, and decision making. Care options and quality metrics should reflect a focus on patients' priorities. Clinician-patient partnerships should reflect patients knowing their health goals and clinicians knowing how to achieve them. Access to specialty expertise should not require visits. Stakeholders' recommendations suggest health care redesigns that incorporate patients' health priorities into care decisions and realign relationships across patients and clinicians.
Fast solar radiation pressure modelling with ray tracing and multiple reflections
NASA Astrophysics Data System (ADS)
Li, Zhen; Ziebart, Marek; Bhattarai, Santosh; Harrison, David; Grey, Stuart
2018-05-01
Physics based SRP (Solar Radiation Pressure) models using ray tracing methods are powerful tools when modelling the forces on complex real world space vehicles. Currently high resolution (1 mm) ray tracing with secondary intersections is done on high performance computers at UCL (University College London). This study introduces the BVH (Bounding Volume Hierarchy) into the ray tracing approach for physics based SRP modelling and makes it possible to run high resolution analysis on personal computers. The ray tracer is both general and efficient enough to cope with the complex shape of satellites and multiple reflections (three or more, with no upper limit). In this study, the traditional ray tracing technique is introduced in the first place and then the BVH is integrated into the ray tracing. Four aspects of the ray tracer were tested for investigating the performance including runtime, accuracy, the effects of multiple reflections and the effects of pixel array resolution.Test results in runtime on GPS IIR and Galileo IOV (In Orbit Validation) satellites show that the BVH can make the force model computation 30-50 times faster. The ray tracer has an absolute accuracy of several nanonewtons by comparing the test results for spheres and planes with the analytical computations. The multiple reflection effects are investigated both in the intersection number and acceleration on GPS IIR, Galileo IOV and Sentinel-1 spacecraft. Considering the number of intersections, the 3rd reflection can capture 99.12 %, 99.14 % , and 91.34 % of the total reflections for GPS IIR, Galileo IOV satellite bus and the Sentinel-1 spacecraft respectively. In terms of the multiple reflection effects on the acceleration, the secondary reflection effect for Galileo IOV satellite and Sentinel-1 can reach 0.2 nm /s2 and 0.4 nm /s2 respectively. The error percentage in the accelerations magnitude results show that the 3rd reflection should be considered in order to make it less than 0.035 % . The pixel array resolution tests show that the dimensions of the components have to be considered when choosing the spacing of the pixel in order not to miss some components of the satellite in ray tracing. This paper presents the first systematic and quantitative study of the secondary and higher order intersection effects. It shows conclusively the effect is non-negligible for certain classes of misson.
Ion Acceleration by Multiple Reflections at Martian Bow Shock
NASA Astrophysics Data System (ADS)
Yamauchi, M.; Futaana, Y.; Fedorov, A.; Frahm, R. A.; Dubinin, E.; Lundin, R.; Sauvaud, J.-A.; Winningham, J. D.; Barabash, S.; Holmström, H.
2012-04-01
The ion mass analyzer (IMA) on board Mars Express revealed bundled structures of ions in the energy domain within a distance of a proton gyroradius from the Martian bow shock. Seven prominent traversals during 2005 were examined when the energy-bunched structure was observed together with pick-up ions of exospheric origin, the latter of which is used to determine the local magnetic field orientation from its circular trajectory in velocity space. These seven traversals include different bow shock configurations: (a) quasi-perpendicular shock with its specular direction of the solar wind more perpendicular to the magnetic field (QT), (b) quasi-perpendicular shock with its specular reflection direction of the solar wind more along the magnetic field (FS), and (c) quasi-parallel (QL) shock. In all seven cases, the velocity components of the energy-bunched structure are consistent with multiple specular reflections of the solar wind at the bow shock up to at least two reflections. The accelerated solar wind ions after two specular reflections have large parallel components with respect to the magnetic field for the QL shock whereas the field-aligned speed is much smaller than the perpendicular speed for the QT shock. The reflected ions escape into the solar wind when and only when the reflection is in the field-aligned direction.
Surface albedo from bidirectional reflectance
NASA Technical Reports Server (NTRS)
Ranson, K. J.; Irons, J. R.; Daughtry, C. S. T.
1991-01-01
The validity of integrating over discrete wavelength bands is examined to estimate total shortwave bidirectional reflectance of vegetated and bare soil surfaces. Methods for estimating albedo from multiple angle, discrete wavelength band radiometer measurements are studied. These methods include a numerical integration technique and the integration of an empirically derived equation for bidirectional reflectance. It is concluded that shortwave albedos estimated through both techniques agree favorably with the independent pyranometer measurements. Absolute rms errors are found to be 0.5 percent or less for both grass sod and bare soil surfaces.
Weighted least-square approach for simultaneous measurement of multiple reflective surfaces
NASA Astrophysics Data System (ADS)
Tang, Shouhong; Bills, Richard E.; Freischlad, Klaus
2007-09-01
Phase shifting interferometry (PSI) is a highly accurate method for measuring the nanometer-scale relative surface height of a semi-reflective test surface. PSI is effectively used in conjunction with Fizeau interferometers for optical testing, hard disk inspection, and semiconductor wafer flatness. However, commonly-used PSI algorithms are unable to produce an accurate phase measurement if more than one reflective surface is present in the Fizeau interferometer test cavity. Examples of test parts that fall into this category include lithography mask blanks and their protective pellicles, and plane parallel optical beam splitters. The plane parallel surfaces of these parts generate multiple interferograms that are superimposed in the recording plane of the Fizeau interferometer. When using wavelength shifting in PSI the phase shifting speed of each interferogram is proportional to the optical path difference (OPD) between the two reflective surfaces. The proposed method is able to differentiate each underlying interferogram from each other in an optimal manner. In this paper, we present a method for simultaneously measuring the multiple test surfaces of all underlying interferograms from these superimposed interferograms through the use of a weighted least-square fitting technique. The theoretical analysis of weighted least-square technique and the measurement results will be described in this paper.
Ion acceleration by multiple reflections at Martian bow shock
NASA Astrophysics Data System (ADS)
Yamauchi, M.; Futaana, Y.; Fedorov, A.; Frahm, R. A.; Dubinin, E.; Lundin, R.; Sauvaud, J.-A.; Winningham, J. D.; Barabash, S.; Holmström, M.
2012-02-01
The ion mass analyzer (IMA) on board Mars Express revealed bundled structures of ions in the energy domain within a distance of a proton gyroradius from the Martian bow shock. Seven prominent traversals during 2005 were examined when the energy-bunched structure was observed together with pick-up ions of exospheric origin, the latter of which is used to determine the local magnetic field orientation from its circular trajectory in velocity space. These seven traversals include different bow shock configurations: (a) quasi-perpendicular shock with its specular direction of the solar wind more perpendicular to the magnetic field (QT), (b) quasi-perpendicular shock with its specular reflection direction of the solar wind more along the magnetic field (FS), and (c) quasi-parallel (QL) shock. In all seven cases, the velocity components of the energy-bunched structure are consistent with multiple specular reflections of the solar wind at the bow shock up to at least two reflections. The accelerated solar wind ions after two specular reflections have large parallel components with respect to the magnetic field for both QL cases whereas the field-aligned speed is much smaller than the perpendicular speed for all QT cases.
Cone and trumpet concentrators in light of the general edge-ray theorem
NASA Astrophysics Data System (ADS)
Ries, Harald; Spirkl, Wolfgang; Winston, Roland
1995-08-01
Cone and trumpet are nonimaging concentrators which do not obey the traditional edge-ray principle. The latter states that edge rays from the source should be transferred to the edge of the target. These concentrators have traditionally been described in terms of the heuristic flow line principle. The edge-ray theorem has been generalized to include nonimaging reflectors with multiple reflections. One includes all multiply reflected rays as an auxiliary domain. The general edge-ray theorem then states that the edge rays to the union of source and auxiliary domain must be reflected to edge of the union of target and auxiliary domain by the first reflection. We show the setup for which cone and trumpet constitute perfect nonimaging concentrators in the light of the generalized edge-ray theorem. We discuss the cases where cones are very good approximations for the solutions of nonimaging problems.
Multiple-path model of spectral reflectance of a dyed fabric.
Rogers, Geoffrey; Dalloz, Nicolas; Fournel, Thierry; Hebert, Mathieu
2017-05-01
Experimental results are presented of the spectral reflectance of a dyed fabric as analyzed by a multiple-path model of reflection. The multiple-path model provides simple analytic expressions for reflection and transmission of turbid media by applying the Beer-Lambert law to each path through the medium and summing over all paths, each path weighted by its probability. The path-length probability is determined by a random-walk analysis. The experimental results presented here show excellent agreement with predictions made by the model.
NASA Technical Reports Server (NTRS)
Smith, James A.
1992-01-01
The inversion of the leaf area index (LAI) canopy parameter from optical spectral reflectance measurements is obtained using a backpropagation artificial neural network trained using input-output pairs generated by a multiple scattering reflectance model. The problem of LAI estimation over sparse canopies (LAI < 1.0) with varying soil reflectance backgrounds is particularly difficult. Standard multiple regression methods applied to canopies within a single homogeneous soil type yield good results but perform unacceptably when applied across soil boundaries, resulting in absolute percentage errors of >1000 percent for low LAI. Minimization methods applied to merit functions constructed from differences between measured reflectances and predicted reflectances using multiple-scattering models are unacceptably sensitive to a good initial guess for the desired parameter. In contrast, the neural network reported generally yields absolute percentage errors of <30 percent when weighting coefficients trained on one soil type were applied to predicted canopy reflectance at a different soil background.
NASA Astrophysics Data System (ADS)
Chang, Seung Jin; Lee, Chun Ku; Shin, Yong-June; Park, Jin Bae
2016-12-01
A multiple chirp reflectometry system with a fault estimation process is proposed to obtain multiple resolution and to measure the degree of fault in a target cable. A multiple resolution algorithm has the ability to localize faults, regardless of fault location. The time delay information, which is derived from the normalized cross-correlation between the incident signal and bandpass filtered reflected signals, is converted to a fault location and cable length. The in-phase and quadrature components are obtained by lowpass filtering of the mixed signal of the incident signal and the reflected signal. Based on in-phase and quadrature components, the reflection coefficient is estimated by the proposed fault estimation process including the mixing and filtering procedure. Also, the measurement uncertainty for this experiment is analyzed according to the Guide to the Expression of Uncertainty in Measurement. To verify the performance of the proposed method, we conduct comparative experiments to detect and measure faults under different conditions. Considering the installation environment of the high voltage cable used in an actual vehicle, target cable length and fault position are designed. To simulate the degree of fault, the variety of termination impedance (10 Ω , 30 Ω , 50 Ω , and 1 \\text{k} Ω ) are used and estimated by the proposed method in this experiment. The proposed method demonstrates advantages in that it has multiple resolution to overcome the blind spot problem, and can assess the state of the fault.
NASA Astrophysics Data System (ADS)
Smith, Brandon M.; Stork, David G.; Zhang, Li
2009-01-01
The problem of reconstructing a three-dimensional scene from single or multiple views has been thoroughly studied in the computer vision literature, and recently has been applied to problems in the history of art. Criminisi pioneered the application of single-view metrology to reconstructing the fictive spaces in Renaissance paintings, such as the vault in Masaccio's Trinità and the plaza in Piero della Francesca's Flagellazione. While the vast majority of realist paintings provide but a single view, some provide multiple views, through mirrors depicted within their tableaus. The contemporary American realist Scott Fraser's Three way vanitas is a highly realistic still-life containing three mirrors; each mirror provides a new view of the objects in the tableau. We applied multiple-view reconstruction methods to the direct image and the images reflected by these mirrors to reconstruct the three-dimensional tableau. Our methods estimate virtual viewpoints for each view using the geometric constraints provided by the direct view of the mirror frames, along with the reflected images themselves. Moreover, our methods automatically discover inconsistencies between the different views, including ones that might elude careful scrutiny by eye, for example the fact that the height of the water in the glass differs between the direct view and that in the mirror at the right. We believe our work provides the first application of multiple-view reconstruction to a single painting and will have application to other paintings and questions in the history of art.
Dopamine prediction error responses integrate subjective value from different reward dimensions
Lak, Armin; Stauffer, William R.; Schultz, Wolfram
2014-01-01
Prediction error signals enable us to learn through experience. These experiences include economic choices between different rewards that vary along multiple dimensions. Therefore, an ideal way to reinforce economic choice is to encode a prediction error that reflects the subjective value integrated across these reward dimensions. Previous studies demonstrated that dopamine prediction error responses reflect the value of singular reward attributes that include magnitude, probability, and delay. Obviously, preferences between rewards that vary along one dimension are completely determined by the manipulated variable. However, it is unknown whether dopamine prediction error responses reflect the subjective value integrated from different reward dimensions. Here, we measured the preferences between rewards that varied along multiple dimensions, and as such could not be ranked according to objective metrics. Monkeys chose between rewards that differed in amount, risk, and type. Because their choices were complete and transitive, the monkeys chose “as if” they integrated different rewards and attributes into a common scale of value. The prediction error responses of single dopamine neurons reflected the integrated subjective value inferred from the choices, rather than the singular reward attributes. Specifically, amount, risk, and reward type modulated dopamine responses exactly to the extent that they influenced economic choices, even when rewards were vastly different, such as liquid and food. This prediction error response could provide a direct updating signal for economic values. PMID:24453218
Ahn, Jae-Hyun; Park, Young-Je; Kim, Wonkook; Lee, Boram
2016-12-26
An estimation of the aerosol multiple-scattering reflectance is an important part of the atmospheric correction procedure in satellite ocean color data processing. Most commonly, the utilization of two near-infrared (NIR) bands to estimate the aerosol optical properties has been adopted for the estimation of the effects of aerosols. Previously, the operational Geostationary Color Ocean Imager (GOCI) atmospheric correction scheme relies on a single-scattering reflectance ratio (SSE), which was developed for the processing of the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) data to determine the appropriate aerosol models and their aerosol optical thicknesses. The scheme computes reflectance contributions (weighting factor) of candidate aerosol models in a single scattering domain then spectrally extrapolates the single-scattering aerosol reflectance from NIR to visible (VIS) bands using the SSE. However, it directly applies the weight value to all wavelengths in a multiple-scattering domain although the multiple-scattering aerosol reflectance has a non-linear relationship with the single-scattering reflectance and inter-band relationship of multiple scattering aerosol reflectances is non-linear. To avoid these issues, we propose an alternative scheme for estimating the aerosol reflectance that uses the spectral relationships in the aerosol multiple-scattering reflectance between different wavelengths (called SRAMS). The process directly calculates the multiple-scattering reflectance contributions in NIR with no residual errors for selected aerosol models. Then it spectrally extrapolates the reflectance contribution from NIR to visible bands for each selected model using the SRAMS. To assess the performance of the algorithm regarding the errors in the water reflectance at the surface or remote-sensing reflectance retrieval, we compared the SRAMS atmospheric correction results with the SSE atmospheric correction using both simulations and in situ match-ups with the GOCI data. From simulations, the mean errors for bands from 412 to 555 nm were 5.2% for the SRAMS scheme and 11.5% for SSE scheme in case-I waters. From in situ match-ups, 16.5% for the SRAMS scheme and 17.6% scheme for the SSE scheme in both case-I and case-II waters. Although we applied the SRAMS algorithm to the GOCI, it can be applied to other ocean color sensors which have two NIR wavelengths.
NASA Astrophysics Data System (ADS)
Wang, Xiu-lin; Wei, Zheng; Wang, Rui; Huang, Wen-cai
2018-05-01
A self-mixing interferometer (SMI) with resolution twenty times higher than that of a conventional interferometer is developed by multiple reflections. Only by employing a simple external reflecting mirror, the multiple-pass optical configuration can be constructed. The advantage of the configuration is simple and easy to make the light re-injected back into the laser cavity. Theoretical analysis shows that the resolution of measurement is scalable by adjusting the number of reflections. The experiment shows that the proposed method has the optical resolution of approximate λ/40. The influence of displacement sensitivity gain ( G) is further analyzed and discussed in practical experiments.
Taxation of oil and gas revenues: Norway
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stauffer, T.R.
1982-04-01
Fiscalization of petroleum in Norway is a multidimensional process, which includes the conventional components of explicit taxation but also involves implicit nontax economic burdens. The latter are often even more important than the taxes themselves. The multidimensional fiscal structure reflects the multiple purposes of petroleum taxation in Norway, of which revenue collection appears to be but one. Given the multiple objectives, it is therefore not surprising that the components are partly inconsistent and contradictory.
Trends in Community Development: Looking Back, Looking Forward.
ERIC Educational Resources Information Center
Miller, Chris; And Others
1990-01-01
Includes "Community Work in the U.K.: Reflections on the 1980s" (Miller, Bryant); "Multiplication and Divisions: Trends in Community Development in Ireland since the 1960s" (Cinneide, Walsh); "Reconstruction to Deconstruction: The Transformation of Community Work in Australia" (Meekosha; Mowbray): "Community…
Method and apparatus for removing unwanted reflections from an interferometer
NASA Technical Reports Server (NTRS)
Steimle, Lawrence J. (Inventor); Thiessen, David L. (Inventor)
1994-01-01
A device for eliminating unwanted reflections from refractive optical elements in an optical system is provided. The device operates to prevent desired multiple fringe patterns from being obscured by reflections from refractive elements positioned in proximity to a focal plane of the system. The problem occurs when an optical beam is projected into, and reflected back out of, the optical system. Surfaces of the refractive elements reflect portions of the beam which interfere with portions of the beam which are transmitted through the refractive elements. Interference between the reflected and transmitted portions of the beam produce multiple fringe sets which tend to obscure desired interference fringes. With the refractive optical element in close proximity to the focal plane of the system, the undesired reflected light reflects at an angle 180 degrees opposite from the desired transmitted beam. The device exploits the 180-degree offset, or rotational shear, of the undesired reflected light by providing an optical stop for blocking one-half of the cross-section of the test beam. By blocking one-half of the test beam, the undesired offset beam is blocked, while the returning transmitted beam passes into the optical system unaffected. An image is thereby produced from only the desired transmitted beam. In one configuration, the blocking device includes a semicircular aperture which is caused to rotate about the axis of the test beam. By rotating, all portions of the test beam are cyclically projected into the optical system to thereby produce a complete test image. The rotating optical stop is preferably caused to rotate rapidly to eliminate flicker in the resulting image.
Solar photovoltaic reflective trough collection structure
Anderson, Benjamin J.; Sweatt, William C.; Okandan, Murat; Nielson, Gregory N.
2015-11-19
A photovoltaic (PV) solar concentration structure having at least two troughs encapsulated in a rectangular parallelepiped optical plastic structure, with the troughs filled with an optical plastic material, the troughs each having a reflective internal surface and approximately parabolic geometry, and the troughs each including photovoltaic cells situated so that light impinging on the optical plastic material will be concentrated onto the photovoltaic cells. Multiple structures can be connected to provide a solar photovoltaic collection system that provides portable, efficient, low-cost electrical power.
Preliminary design and development of a reflectance spectrometer instrument
NASA Technical Reports Server (NTRS)
Mccord, T. B.
1979-01-01
An improved design for the reflectance spectrometer is described to be used on various terrestrial body missions. These improvements were made on the original Lunar Polar Orbiter design. These include a larger entrance mirror, rectangular aperture, multiple optical beams, spatial resolution, and a bandwidth extension to 5 microns. In addition, detailed electronic designs were produced for a charge amplifier and an amplifier/demodulator/integrator. Design of a microprocessor driven test system was begun. Laboratory tests were performed on a tuning fork chopper.
Transfer matrix method for four-flux radiative transfer.
Slovick, Brian; Flom, Zachary; Zipp, Lucas; Krishnamurthy, Srini
2017-07-20
We develop a transfer matrix method for four-flux radiative transfer, which is ideally suited for studying transport through multiple scattering layers. The model predicts the specular and diffuse reflection and transmission of multilayer composite films, including interface reflections, for diffuse or collimated incidence. For spherical particles in the diffusion approximation, we derive closed-form expressions for the matrix coefficients and show remarkable agreement with numerical Monte Carlo simulations for a range of absorption values and film thicknesses, and for an example multilayer slab.
EXPLAINING FOREST COMPOSITION AND BIOMASS ACROSS MULTIPLE BIOGEOGRAPHIC REGIONS
Current scientific concerns regarding the impacts of global change include the responses of forest composition and biomass to rapid changes in climate, and forest gap models, have often been used to address this issue. These models reflect the concept that forest composition and...
Harnessing Multiple Internal Reflections to Design Highly Absorptive Acoustic Metasurfaces
NASA Astrophysics Data System (ADS)
Shen, Chen; Cummer, Steven A.
2018-05-01
The rapid development of metasurfaces has enabled numerous intriguing applications with acoustically thin sheets. Here we report the theory and experimental realization of a nonresonant sound-absorbing strategy using metasurfaces by harnessing multiple internal reflections. We theoretically and numerically show that the higher-order diffraction of thin gradient-index metasurfaces is tied to multiple internal reflections inside the unit cells. Highly absorbing acoustic metasurfaces can be realized by enforcing multiple internal reflections together with a small amount of loss. A reflective gradient-index acoustic metasurface is designed based on the theory, and we further experimentally verify the performance using a three-dimensional printed prototype. Measurements show over 99% energy absorption at the peak frequency and a 95% energy absorption bandwidth of around 600 Hz. The proposed mechanism provides an alternative route for sound absorption without the necessity of high absorption of the individual unit cells.
NASA Technical Reports Server (NTRS)
Lang, Timothy J.; Rutledge, Steven A.; Dolan, Brenda; Krehbiel, Paul; Rison, William; Lindsey, Daniel T.
2013-01-01
Pyrocumulus clouds above three Colorado wildfires (Hewlett Gulch, High Park, and Waldo Canyon; all occurred during summer 2012) electrified and produced small intracloud discharges whenever the smoke plumes grew to high altitudes (over 10 km above mean sea level, or MSL). This occurred during periods of rapid wildfire growth, as indicated by the shortwave infrared channel on a geostationary satellite, as well as by incident reports. In the Hewlett Gulch case, the fire growth led to increased updrafts within the plume, as inferred by multiple- Doppler radar syntheses, which led to the vertical development and subsequent electrification - a life cycle as short as 30 minutes. The lightning, detected by a threedimensional lightning mapping network, was favored in high-altitude regions (10 km MSL) containing modest reflectivities (25 dBZ and lower), 0 dB differential reflectivity, and reduced correlation coefficient (0.6-0.7). This indicated the likely presence of ice particles (crystals and aggregates, possibly rimed) mixed with ash. Though neither multiple-Doppler nor polarimetric observations were available during the electrification of the High Park and Waldo Canyon plumes, their NEXRAD observations showed reflectivity structures consistent with Hewlett Gulch. In addition, polarimetric and multiple-Doppler scanning of unelectrified High Park plumes indicated only irregularly shaped ash, and not ice, was present (i.e., reflectivities < 25 dBZ, differential reflectivity > 5 dB, correlation < 0.4), and there was no broaching of the 10 km altitude. Based on these results, the electrification likely was caused by ice-based processes that did not involve significant amounts of graupel. The results demonstrate the scientific value of multiple-Doppler and polarimetric radar observations of wildfire smoke plumes - including the ability to distinguish between regions of pure hydrometeors, regions of pure ash, and mixtures of both - and also suggest a possible new application for lightning data in monitoring wildfires.
Implementing Technological Solutions within K-12 Contexts: A Comprehensive Route Guide
ERIC Educational Resources Information Center
Subramony, Deepak Prem
2012-01-01
This article seeks to reflect, summarize, and present preexisting understandings from multiple interrelated realms of theory and practice--including diffusion of innovations, needs assessment, change management, systemic change, performance improvement, and what might be described as "socio-culturally cognizant" educational technology--in order to…
2010 CEOS Field Reflectance Intercomparisons Lessons Learned
NASA Technical Reports Server (NTRS)
Thome, Kurtis; Fox, Nigel
2011-01-01
This paper summarizes lessons learned from the 2009 and 2010 joint field campaigns to Tuz Golu, Turkey. Emphasis is placed on the 2010 campaign related to understanding the equipment and measurement protocols, processing schemes, and traceability to SI quantities. Participants in both 2009 and 2010 used an array of measurement approaches to determine surface reflectance. One lesson learned is that even with all of the differences in collection between groups, the differences in reflectance are currently dominated by instrumental artifacts including knowledge of the white reference. Processing methodology plays a limited role once the bi-directional reflectance of the white reference is used rather than a hemispheric-directional value. The lack of a basic set of measurement protocols, or best practices, limits a group s ability to ensure SI traceability and the development of proper error budgets. Finally, rigorous attention to sampling methodology and its impact on instrument behavior is needed. The results of the 2009 and 2010 joint campaigns clearly demonstrate both the need and utility of such campaigns and such comparisons must continue in the future to ensure a coherent set of data that can span multiple sensor types and multiple decades.
Discrete ordinates solutions of nongray radiative transfer with diffusely reflecting walls
NASA Technical Reports Server (NTRS)
Menart, J. A.; Lee, Haeok S.; Kim, Tae-Kuk
1993-01-01
Nongray gas radiation in a plane parallel slab bounded by gray, diffusely reflecting walls is studied using the discrete ordinates method. The spectral equation of transfer is averaged over a narrow wavenumber interval preserving the spectral correlation effect. The governing equations are derived by considering the history of multiple reflections between two reflecting wails. A closure approximation is applied so that only a finite number of reflections have to be explicitly included. The closure solutions express the physics of the problem to a very high degree and show relatively little error. Numerical solutions are obtained by applying a statistical narrow-band model for gas properties and a discrete ordinates code. The net radiative wail heat fluxes and the radiative source distributions are obtained for different temperature profiles. A zeroth-degree formulation, where no wall reflection is handled explicitly, is sufficient to predict the radiative transfer accurately for most cases considered, when compared with increasingly accurate solutions based on explicitly tracing a larger number of wail reflections without any closure approximation applied.
Dong, Yingying; Luo, Ruisen; Feng, Haikuan; Wang, Jihua; Zhao, Jinling; Zhu, Yining; Yang, Guijun
2014-01-01
Differences exist among analysis results of agriculture monitoring and crop production based on remote sensing observations, which are obtained at different spatial scales from multiple remote sensors in same time period, and processed by same algorithms, models or methods. These differences can be mainly quantitatively described from three aspects, i.e. multiple remote sensing observations, crop parameters estimation models, and spatial scale effects of surface parameters. Our research proposed a new method to analyse and correct the differences between multi-source and multi-scale spatial remote sensing surface reflectance datasets, aiming to provide references for further studies in agricultural application with multiple remotely sensed observations from different sources. The new method was constructed on the basis of physical and mathematical properties of multi-source and multi-scale reflectance datasets. Theories of statistics were involved to extract statistical characteristics of multiple surface reflectance datasets, and further quantitatively analyse spatial variations of these characteristics at multiple spatial scales. Then, taking the surface reflectance at small spatial scale as the baseline data, theories of Gaussian distribution were selected for multiple surface reflectance datasets correction based on the above obtained physical characteristics and mathematical distribution properties, and their spatial variations. This proposed method was verified by two sets of multiple satellite images, which were obtained in two experimental fields located in Inner Mongolia and Beijing, China with different degrees of homogeneity of underlying surfaces. Experimental results indicate that differences of surface reflectance datasets at multiple spatial scales could be effectively corrected over non-homogeneous underlying surfaces, which provide database for further multi-source and multi-scale crop growth monitoring and yield prediction, and their corresponding consistency analysis evaluation.
Dong, Yingying; Luo, Ruisen; Feng, Haikuan; Wang, Jihua; Zhao, Jinling; Zhu, Yining; Yang, Guijun
2014-01-01
Differences exist among analysis results of agriculture monitoring and crop production based on remote sensing observations, which are obtained at different spatial scales from multiple remote sensors in same time period, and processed by same algorithms, models or methods. These differences can be mainly quantitatively described from three aspects, i.e. multiple remote sensing observations, crop parameters estimation models, and spatial scale effects of surface parameters. Our research proposed a new method to analyse and correct the differences between multi-source and multi-scale spatial remote sensing surface reflectance datasets, aiming to provide references for further studies in agricultural application with multiple remotely sensed observations from different sources. The new method was constructed on the basis of physical and mathematical properties of multi-source and multi-scale reflectance datasets. Theories of statistics were involved to extract statistical characteristics of multiple surface reflectance datasets, and further quantitatively analyse spatial variations of these characteristics at multiple spatial scales. Then, taking the surface reflectance at small spatial scale as the baseline data, theories of Gaussian distribution were selected for multiple surface reflectance datasets correction based on the above obtained physical characteristics and mathematical distribution properties, and their spatial variations. This proposed method was verified by two sets of multiple satellite images, which were obtained in two experimental fields located in Inner Mongolia and Beijing, China with different degrees of homogeneity of underlying surfaces. Experimental results indicate that differences of surface reflectance datasets at multiple spatial scales could be effectively corrected over non-homogeneous underlying surfaces, which provide database for further multi-source and multi-scale crop growth monitoring and yield prediction, and their corresponding consistency analysis evaluation. PMID:25405760
System and method for image registration of multiple video streams
Dillavou, Marcus W.; Shum, Phillip Corey; Guthrie, Baron L.; Shenai, Mahesh B.; Deaton, Drew Steven; May, Matthew Benton
2018-02-06
Provided herein are methods and systems for image registration from multiple sources. A method for image registration includes rendering a common field of interest that reflects a presence of a plurality of elements, wherein at least one of the elements is a remote element located remotely from another of the elements and updating the common field of interest such that the presence of the at least one of the elements is registered relative to another of the elements.
Project Physics Tests 4, Light and Electromagnetism.
ERIC Educational Resources Information Center
Harvard Univ., Cambridge, MA. Harvard Project Physics.
Test items relating to Project Physics Unit 4 are presented in this booklet. Included are 70 multiple-choice and 22 problem-and-essay questions. Concepts of light and electromagnetism are examined on charges, reflection, electrostatic forces, electric potential, speed of light, electromagnetic waves and radiations, Oersted's and Faraday's work,…
Providing Students with Severe Disabilities Access to the General Education Curriculum
ERIC Educational Resources Information Center
Olson, Amy; Leko, Melinda M.; Roberts, Carly A.
2016-01-01
This case study explored how multiple educational personnel in a middle school identified as an exemplar of inclusive education defined and provided students with severe disabilities access to the general education curriculum. Data sources including a questionnaire, interviews, observations, observation reflections, and artifacts were collected…
Reflections on "Petit Battement sur le Cou de Pied": Is It Still Relevant?
ERIC Educational Resources Information Center
Paskevska, Anna
2007-01-01
This article presents multiple perspectives of "petit battement sur le cou de pied". These perspectives include historical, biomechanical, and pedagogic points of view. The article offers useful information for ballet specialists and applied research studies aimed at ballet pedagogy. (Contains 2 tables and 5 figures.)
Purpose and Pedagogy: A Conceptual Model for an ePortfolio
ERIC Educational Resources Information Center
Buyarski, Catherine A.; Aaron, Robert W.; Hansen, Michele J.; Hollingsworth, Cynthia D.; Johnson, Charles A.; Kahn, Susan; Landis, Cynthia M.; Pedersen, Joan S.; Powell, Amy A.
2015-01-01
This conceptual model emerged from the need to balance multiple purposes and perspectives associated with developing an ePortfolio designed to promote student development and success. A comprehensive review of literature from various disciplines, theoretical frameworks, and scholarship, including self-authorship, reflection, ePortfolio pedagogy,…
Revising the New York State Social Studies Curriculum.
ERIC Educational Resources Information Center
Sobol, Thomas
1993-01-01
Discusses the need to revise New York State's social studies curriculum to reflect the nation's diversity in a fair way, presenting a less biased, more realistic view of history. The curriculum should cultivate multiple perspectives, teach about common traditions, include examples of many peoples, and tell the whole story. (SM)
Cloud Effects in Hyperspectral Imagery from First-Principles Scene Simulations
2009-01-01
SPIE. One print or electronic copy may be made for personal use only. Systematic or multiple reproduction, or distribution to multiple locations...scattering and absorption, scattering events, surface scattering with material-dependent bidirectional reflectances, multiple surface adjacency...aerosols or clouds, they may be absorbed, or they may reflect off the ground or an object. A given photon may undergo multiple scattering events
Karkabi, Khaled; Wald, Hedy S; Cohen Castel, Orit
2014-01-01
Reflective capacity is integral to core healthcare professional practice competencies. Reflection plays a central role in teacher education as reflecting on teaching behaviours with critical analysis can potentially improve teaching practice. The humanities including narrative and the visual arts can serve as a valuable tool for fostering reflection. We conducted a multinational faculty development workshop aiming to enhance reflective capacity in medical educators by using a combination of abstract paintings and narratives. Twenty-three family physicians or physicians-in-training from 10 countries participated in the workshop. Qualitative assessment of the workshop showed that the combined use of art and narrative was well received and perceived as contributing to the reflective exercise. Participants generally felt that viewing abstract paintings had facilitated a valuable mood transformation and prepared them emotionally for the reflective writing. Our analysis found that the following themes emerged from participants’ responses: (1) narratives from different countries are similar; (2) the use of art helped access feelings; (3) viewing abstract paintings facilitated next steps; (4) writing reflective narratives promoted examination of educational challenges, compassion for self and other, and building an action plan; and (5) sharing of narrative was helpful for fostering active listening and appreciating multiple perspectives. Future research might include comparing outcomes for a group participating in arts–narrative-based workshops with those of a control group using only reflective narrative or in combination with figurative art, and implementing a combination of qualitative and quantitative methods of assessment. PMID:24273319
Multi- and hyperspectral scene modeling
NASA Astrophysics Data System (ADS)
Borel, Christoph C.; Tuttle, Ronald F.
2011-06-01
This paper shows how to use a public domain raytracer POV-Ray (Persistence Of Vision Raytracer) to render multiand hyper-spectral scenes. The scripting environment allows automatic changing of the reflectance and transmittance parameters. The radiosity rendering mode allows accurate simulation of multiple-reflections between surfaces and also allows semi-transparent surfaces such as plant leaves. We show that POV-Ray computes occlusion accurately using a test scene with two blocks under a uniform sky. A complex scene representing a plant canopy is generated using a few lines of script. With appropriate rendering settings, shadows cast by leaves are rendered in many bands. Comparing single and multiple reflection renderings, the effect of multiple reflections is clearly visible and accounts for 25% of the overall apparent canopy reflectance in the near infrared.
ERIC Educational Resources Information Center
Daniel, Shannon M.
2015-01-01
In this self-study, the author reflects on her implementation of empathetic, critical integrations of multiple perspectives (ECI), which she designed to afford preservice teachers the opportunity to discuss and collectively reflect upon the oft-diverging multiple perspectives, values, and practices they experience during their practicum (Daniel,…
NASA Astrophysics Data System (ADS)
Ahmed Mohamed, E. T.; Schubert, S.; Gilberger, T. W.; Kamanyi, A., Jr.; Wannemacher, R.; Grill, W.
2006-03-01
Acoustic and optical multiple contrast microscopy has been employed in order to explore characterizable parameters of red blood cells, including cells infected by the parasite Plasmodium falciparum, in order to investigate cellular modifications caused by the infection and to identify possible detection schemes for disease monitoring. Imaging schemes were based on fluorescence, optical transmission, optical reflection, and amplitude and phase of ultrasound reflected from the cells. Contrast variations observed in acoustic microscopy, but not in optical microscopy, were tentatively ascribed to changes caused by the infection.
Formation Flight of Multiple UAVs via Onboard Sensor Information Sharing.
Park, Chulwoo; Cho, Namhoon; Lee, Kyunghyun; Kim, Youdan
2015-07-17
To monitor large areas or simultaneously measure multiple points, multiple unmanned aerial vehicles (UAVs) must be flown in formation. To perform such flights, sensor information generated by each UAV should be shared via communications. Although a variety of studies have focused on the algorithms for formation flight, these studies have mainly demonstrated the performance of formation flight using numerical simulations or ground robots, which do not reflect the dynamic characteristics of UAVs. In this study, an onboard sensor information sharing system and formation flight algorithms for multiple UAVs are proposed. The communication delays of radiofrequency (RF) telemetry are analyzed to enable the implementation of the onboard sensor information sharing system. Using the sensor information sharing, the formation guidance law for multiple UAVs, which includes both a circular and close formation, is designed. The hardware system, which includes avionics and an airframe, is constructed for the proposed multi-UAV platform. A numerical simulation is performed to demonstrate the performance of the formation flight guidance and control system for multiple UAVs. Finally, a flight test is conducted to verify the proposed algorithm for the multi-UAV system.
Formation Flight of Multiple UAVs via Onboard Sensor Information Sharing
Park, Chulwoo; Cho, Namhoon; Lee, Kyunghyun; Kim, Youdan
2015-01-01
To monitor large areas or simultaneously measure multiple points, multiple unmanned aerial vehicles (UAVs) must be flown in formation. To perform such flights, sensor information generated by each UAV should be shared via communications. Although a variety of studies have focused on the algorithms for formation flight, these studies have mainly demonstrated the performance of formation flight using numerical simulations or ground robots, which do not reflect the dynamic characteristics of UAVs. In this study, an onboard sensor information sharing system and formation flight algorithms for multiple UAVs are proposed. The communication delays of radiofrequency (RF) telemetry are analyzed to enable the implementation of the onboard sensor information sharing system. Using the sensor information sharing, the formation guidance law for multiple UAVs, which includes both a circular and close formation, is designed. The hardware system, which includes avionics and an airframe, is constructed for the proposed multi-UAV platform. A numerical simulation is performed to demonstrate the performance of the formation flight guidance and control system for multiple UAVs. Finally, a flight test is conducted to verify the proposed algorithm for the multi-UAV system. PMID:26193281
Channel Model Optimization with Reflection Residual Component for Indoor MIMO-VLC System
NASA Astrophysics Data System (ADS)
Chen, Yong; Li, Tengfei; Liu, Huanlin; Li, Yichao
2017-12-01
A fast channel modeling method is studied to solve the problem of reflection channel gain for multiple input multiple output-visible light communications (MIMO-VLC) in the paper. For reducing the computational complexity when associating with the reflection times, no more than 3 reflections are taken into consideration in VLC. We think that higher order reflection link consists of corresponding many times line of sight link and firstly present reflection residual component to characterize higher reflection (more than 2 reflections). We perform computer simulation results for point-to-point channel impulse response, receiving optical power and receiving signal to noise ratio. Based on theoretical analysis and simulation results, the proposed method can effectively reduce the computational complexity of higher order reflection in channel modeling.
Myers, Tanya L; Tonkyn, Russell G; Danby, Tyler O; Taubman, Matthew S; Bernacki, Bruce E; Birnbaum, Jerome C; Sharpe, Steven W; Johnson, Timothy J
2018-04-01
For optical modeling and other purposes, we have created a library of 57 liquids for which we have measured the complex optical constants n and k. These liquids vary in their nature, ranging in properties that include chemical structure, optical band strength, volatility, and viscosity. By obtaining the optical constants, one can model most optical phenomena in media and at interfaces including reflection, refraction, and dispersion. Based on the works of others, we have developed improved protocols using multiple path lengths to determine the optical constants n/k for dozens of liquids, including inorganic, organic, and organophosphorus compounds. Detailed descriptions of the measurement and data reduction protocols are discussed; agreement of the derived optical constant n and k values with literature values are presented. We also present results using the n/k values as applied to an optical modeling scenario whereby the derived data are presented and tested for models of 1 µm and 100 µm layers for dimethyl methylphosphonate (DMMP) on both metal (aluminum) and dielectric (soda lime glass) substrates to show substantial differences between the reflected signal from highly reflective substrates and less-reflective substrates.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Myers, Tanya L.; Tonkyn, Russell G.; Danby, Tyler O.
For optical modeling and other purposes, we have created a library of 57 liquids for which we have measured the complex optical constants n and k. These liquids vary in their nature, ranging in properties including chemical structure, optical band strength, volatility and viscosity. By obtaining the optical constants one can in principle model most optical phenomena in media and at interfaces including reflection, refraction and dispersion. Based on the original methods of J.E. Bertie et al.1 [1Bert1], we have developed improved protocols using multiple path lengths to determine the optical constants n/k for dozens of liquids, including inorganic, organicmore » and organophosphorus compounds. Detailed descriptions of the measurement and data reduction protocols are discussed; agreement of the derived optical constant n and k values with literature values are presented. We also present results using the n/k values as applied to an optical modeling scenario whereby the derived data are presented and tested for models of 1 µm and 100 µm layers for DMMP (dimethyl methyl phosphonate) on both metal (aluminum) and dielectric (soda lime glass) substrates to show substantial differences between the reflected signal from highly reflective substrates and less-reflective substrates.« less
North, Sarah; Giddens, Jean
2013-10-01
Multiple challenges must be addressed when educational research is being conducted that involves a teaching innovation at multiple sites over time, including the consistent adoption and use of the intervention, attrition, response rates, and other aspects related to managing a complex study. After an 18-month nursing education study was conducted at multiple institutions across the United States, the authors' study team reflected on strategies that worked well, the challenges faced, and what could have been done differently. This article details the challenges and offers recommendations for other researchers conducting similar studies. Recommendations related to communication and engagement, innovation fidelity, survey fatigue, multiple institutional review board applications, and flexibility are provided. Copyright 2013, SLACK Incorporated.
Scaling in cognitive performance reflects multiplicative multifractal cascade dynamics
Stephen, Damian G.; Anastas, Jason R.; Dixon, James A.
2012-01-01
Self-organized criticality purports to build multi-scaled structures out of local interactions. Evidence of scaling in various domains of biology may be more generally understood to reflect multiplicative interactions weaving together many disparate scales. The self-similarity of power-law scaling entails homogeneity: fluctuations distribute themselves similarly across many spatial and temporal scales. However, this apparent homogeneity can be misleading, especially as it spans more scales. Reducing biological processes to one power-law relationship neglects rich cascade dynamics. We review recent research into multifractality in executive-function cognitive tasks and propose that scaling reflects not criticality but instead interactions across multiple scales and among fluctuations of multiple sizes. PMID:22529819
Multiple-reflection optical gas cell
Matthews, Thomas G.
1983-01-01
A multiple-reflection optical cell for Raman or fluorescence gas analysis consists of two spherical mirrors positioned transverse to a multiple-pass laser cell in a confronting plane-parallel alignment. The two mirrors are of equal diameter but possess different radii of curvature. The spacing between the mirrors is uniform and less than half of the radius of curvature of either mirror. The mirror of greater curvature possesses a small circular portal in its center which is the effective point source for conventional F1 double lens collection optics of a monochromator-detection system. Gas to be analyzed is flowed into the cell and irradiated by a multiply-reflected composite laser beam centered between the mirrors of the cell. Raman or fluorescence radiation originating from a large volume within the cell is (1) collected via multiple reflections with the cell mirrors, (2) partially collimated and (3) directed through the cell portal in a geometric array compatible with F1 collection optics.
Hierarchical analysis of species distributions and abundance across environmental gradients
Jeffery Diez; Ronald H. Pulliam
2007-01-01
Abiotic and biotic processes operate at multiple spatial and temporal scales to shape many ecological processes, including species distributions and demography. Current debate about the relative roles of niche-based and stochastic processes in shaping species distributions and community composition reflects, in part, the challenge of understanding how these processes...
Developing a Computerised Multiple Elements Test for Organisational Difficulties
ERIC Educational Resources Information Center
Hynes, Sinead M.; Fish, Jessica; Evans, Jonathan J.; Manly, Tom
2015-01-01
Executive function is best measured in loosely structured, multi-component tasks that reflect real-life demands. These tasks require participants to develop a strategy, keep a plan in mind and monitor time. Errors include ignoring stated goals ("goal neglect"), over-allocation of time to one task and violating rules. Teasing apart such…
Distinct encoding of risk and value in economic choice between multiple risky options☆
Wright, Nicholas D.; Symmonds, Mkael; Dolan, Raymond J.
2013-01-01
Neural encoding of value-based stimuli is suggested to involve representations of summary statistics, including risk and expected value (EV). A more complex, but ecologically more common, context is when multiple risky options are evaluated together. However, it is unknown whether encoding related to option evaluation in these situations involves similar principles. Here we employed fMRI during a task that parametrically manipulated EV and risk in two simultaneously presented lotteries, both of which contained either gains or losses. We found representations of EV in medial prefrontal cortex and anterior insula, an encoding that was dependent on which option was chosen (i.e. chosen and unchosen EV) and whether the choice was over gains or losses. Parietal activity reflected whether the riskier or surer option was selected, whilst activity in a network of regions that also included parietal cortex reflected both combined risk and difference in risk for the two options. Our findings provide support for the idea that summary statistics underpin a representation of value-based stimuli, and further that these summary statistics undergo distinct forms of encoding. PMID:23684860
Re-evaluation of model-based light-scattering spectroscopy for tissue spectroscopy
Lau, Condon; Šćepanović, Obrad; Mirkovic, Jelena; McGee, Sasha; Yu, Chung-Chieh; Fulghum, Stephen; Wallace, Michael; Tunnell, James; Bechtel, Kate; Feld, Michael
2009-01-01
Model-based light scattering spectroscopy (LSS) seemed a promising technique for in-vivo diagnosis of dysplasia in multiple organs. In the studies, the residual spectrum, the difference between the observed and modeled diffuse reflectance spectra, was attributed to single elastic light scattering from epithelial nuclei, and diagnostic information due to nuclear changes was extracted from it. We show that this picture is incorrect. The actual single scattering signal arising from epithelial nuclei is much smaller than the previously computed residual spectrum, and does not have the wavelength dependence characteristic of Mie scattering. Rather, the residual spectrum largely arises from assuming a uniform hemoglobin distribution. In fact, hemoglobin is packaged in blood vessels, which alters the reflectance. When we include vessel packaging, which accounts for an inhomogeneous hemoglobin distribution, in the diffuse reflectance model, the reflectance is modeled more accurately, greatly reducing the amplitude of the residual spectrum. These findings are verified via numerical estimates based on light propagation and Mie theory, tissue phantom experiments, and analysis of published data measured from Barrett’s esophagus. In future studies, vessel packaging should be included in the model of diffuse reflectance and use of model-based LSS should be discontinued. PMID:19405760
Code division multiple access signaling for modulated reflector technology
Briles, Scott D [Los Alamos, NM
2012-05-01
A method and apparatus for utilizing code division multiple access in modulated reflectance transmissions comprises the steps of generating a phase-modulated reflectance data bit stream; modifying the modulated reflectance data bit stream; providing the modified modulated reflectance data bit stream to a switch that connects an antenna to an infinite impedance in the event a "+1" is to be sent, or connects the antenna to ground in the event a "0" or a "-1" is to be sent.
Laser Spiderweb Sensor Used with Portable Handheld Devices
NASA Technical Reports Server (NTRS)
Scott, David C. (Inventor); Ksendzov, Alexander (Inventor); George, Warren P. (Inventor); Smith, James A. (Inventor); Steinkraus, Joel M. (Inventor); Hofmann, Douglas C. (Inventor); Aljabri, Abdullah S. (Inventor); Bendig, Rudi M. (Inventor)
2017-01-01
A portable spectrometer, including a smart phone case storing a portable spectrometer, wherein the portable spectrometer includes a cavity; a source for emitting electromagnetic radiation that is directed on a sample in the cavity, wherein the electromagnetic radiation is reflected within the cavity to form multiple passes of the electromagnetic radiation through the sample; a detector for detecting the electromagnetic radiation after the electromagnetic radiation has made the multiple passes through the sample in the cavity, the detector outputting a signal in response to the detecting; and a device for communicating the signal to a smart phone, wherein the smart phone executes an application that performs a spectral analysis of the signal.
Surface plasmon resonance spectroscopy sensor and methods for using same
Anderson, Brian Benjamin; Nave, Stanley Eugene
2002-01-01
A surface plasmon resonance ("SPR") probe with a detachable sensor head and system and methods for using the same in various applications is described. The SPR probe couples fiber optic cables directly to an SPR substrate that has a generally planar input surface and a generally curved reflecting surface, such as a substrate formed as a hemisphere. Forming the SPR probe in this manner allows the probe to be miniaturized and operate without the need for high precision, expensive and bulky collimating or focusing optics. Additionally, the curved reflecting surface of the substrate can be coated with one or multiple patches of sensing medium to allow the probe to detect for multiple analytes of interest or to provide multiple readings for comparison and higher precision. Specific applications for the probe are disclosed, including extremely high sensitive relative humidity and dewpoint detection for, e.g., moisture-sensitive environment such as volatile chemical reactions. The SPR probe disclosed operates with a large dynamic range and provides extremely high quality spectra despite being robust enough for field deployment and readily manufacturable.
Lamp method and apparatus using multiple reflections
MacLennan, Donald A.; Turner, Brian; Kipling, Kent
1999-01-01
A method wherein the light in a sulfur or selenium lamp is reflected through the fill a multiplicity of times to convert ultraviolet radiation to visible. A light emitting device comprised of an electrodeless envelope which bears a light reflecting covering around a first portion which does not crack due to differential thermal expansion and which has a second portion which comprises a light transmissive aperture.
Ha, Na Young; Ohtsuka, Youko; Jeong, Soon Moon; Nishimura, Suzushi; Suzaki, Goroh; Takanishi, Yoichi; Ishikawa, Ken; Takezoe, Hideo
2008-01-01
A cholesteric liquid crystal (CLC) is a self-assembled photonic crystal formed by rodlike molecules, including chiral molecules, that arrange themselves in a helical fashion. The CLC has a single photonic bandgap and an associated one-colour reflection band for circularly polarized light with the same handedness as the CLC helix (selective reflection). These optical characteristics, particularly the circular polarization of the reflected light, are attractive for applications in reflective colour displays without using a backlight, for use as polarizers or colour filters and for mirrorless lasing. Recently, we showed by numerical simulation that simultaneous multicolour reflection is possible by introducing fibonaccian phase defects. Here, we design and fabricate a CLC system consisting of thin isotropic films and of polymeric CLC films, and demonstrate experimentally simultaneous red, green and blue reflections (multiple photonic bandgaps) using the single-pitched polymeric CLC films. The experimental reflection spectra are well simulated by calculations. The presented system can extend applications of CLCs to a wide-band region and could give rise to new photonic devices, in which white or multicolour light is manipulated.
Odendaal, Willem; Atkins, Salla; Lewin, Simon
2016-12-15
Formative programme evaluations assess intervention implementation processes, and are seen widely as a way of unlocking the 'black box' of any programme in order to explore and understand why a programme functions as it does. However, few critical assessments of the methods used in such evaluations are available, and there are especially few that reflect on how well the evaluation achieved its objectives. This paper describes a formative evaluation of a community-based lay health worker programme for TB and HIV/AIDS clients across three low-income communities in South Africa. It assesses each of the methods used in relation to the evaluation objectives, and offers suggestions on ways of optimising the use of multiple, mixed-methods within formative evaluations of complex health system interventions. The evaluation's qualitative methods comprised interviews, focus groups, observations and diary keeping. Quantitative methods included a time-and-motion study of the lay health workers' scope of practice and a client survey. The authors conceptualised and conducted the evaluation, and through iterative discussions, assessed the methods used and their results. Overall, the evaluation highlighted programme issues and insights beyond the reach of traditional single methods evaluations. The strengths of the multiple, mixed-methods in this evaluation included a detailed description and nuanced understanding of the programme and its implementation, and triangulation of the perspectives and experiences of clients, lay health workers, and programme managers. However, the use of multiple methods needs to be carefully planned and implemented as this approach can overstretch the logistic and analytic resources of an evaluation. For complex interventions, formative evaluation designs including multiple qualitative and quantitative methods hold distinct advantages over single method evaluations. However, their value is not in the number of methods used, but in how each method matches the evaluation questions and the scientific integrity with which the methods are selected and implemented.
Polarized BRDF for coatings based on three-component assumption
NASA Astrophysics Data System (ADS)
Liu, Hong; Zhu, Jingping; Wang, Kai; Xu, Rong
2017-02-01
A pBRDF(polarized bidirectional reflection distribution function) model for coatings is given based on three-component reflection assumption in order to improve the polarized scattering simulation capability for space objects. In this model, the specular reflection is given based on microfacet theory, the multiple reflection and volume scattering are given separately according to experimental results. The polarization of specular reflection is considered from Fresnel's law, and both multiple reflection and volume scattering are assumed depolarized. Simulation and measurement results of two satellite coating samples SR107 and S781 are given to validate that the pBRDF modeling accuracy can be significantly improved by the three-component model given in this paper.
Replacing backscattering with reduced scattering. A better formulation of reflectance function?
NASA Astrophysics Data System (ADS)
Piskozub, Jacek; McKee, David; Freda, Wlodzimierz
2014-05-01
Modern reflectance formulas all involve backscattering coefficient divided by absorption coefficient (bb/a). The backscattering (or backward scattering) coefficient describes how much of the incident radiation is scattered at angles between 90 and 180 deg. However, water leaving photons are not necessarily backscattered because it is possible for a variable fraction to exit after multiple forward scattering events. Therefore the whole angular function of scattering probability (phase function) influences the reflectance signal. This is the reason why phase functions of identical backscattering ratio may result in different reflectance values, contrary to the universally used formula. This creates the question whether there may exist a better formula using a parameter better describing phase function shape than backscattering ratio. The asymmetry parameter g (the average scattering cosine) is commonly used to parametrize phase functions. A replacement for backscattering should decrease with increasing g. Therefore, the simplest candidate to replace backscattering has the form of b(1-g), where b is the scattering coefficient. Such a parameter is well known in biomedical optics under the name of reduced scattering (sometimes transport scattering). It has even been used in parametrizing reflectance in (highly turbid) human tissues. However no attempt has been made to check its usefulness in marine optics. We perform Monte Carlo radiative transfer calculations of reflectance for multiple combinations of inherent optical properties, including different phase functions. The results are used to create a new reflectance formula as a function of reduced scattering and absorption and test its robustness to changes in phase function shape compared to the traditional bb/a formula. We discuss its usefulness as well as advantages and disadvantages compared to the traditional formulation.
BOREAS RSS-3 Reflectance Measured from a Helicopter-Mounted SE-590
NASA Technical Reports Server (NTRS)
Hall, Forrest G. (Editor); Nickeson, Jaime (Editor); Walthall, Charles L.; Loechel, Sara
2000-01-01
The BOREAS RSS-3 team collected multiple remotely sensed data sets from the NASA UH-1 helicopter. This data set includes helicopter-based radiometric measurements of forested sites acquired during BOREAS made with an SE-590 processed to reflectance factors. The data used in this analysis were collected in 1994 during the three BOREAS IFCs at numerous tower and auxiliary sites in both the NSA and the SSA. The 15-degree FOV of the SE-590 yielded a ground resolution of approximately 79 m at the 300-m nominal altitude. The data are provided in tabular ASCII files.
Multiple-wavelength tunable laser
NASA Technical Reports Server (NTRS)
Barnes, Norman P. (Inventor); Walsh, Brian M. (Inventor); Reichle, Donald J. (Inventor)
2010-01-01
A tunable laser includes dispersion optics for separating generated laser pulses into first and second wavelength pulses directed along first and second optical paths. First and second reflective mirrors are disposed in the first and second optical paths, respectively. The laser's output mirror is partially reflective and partially transmissive with respect to the first wavelength and the second wavelength in accordance with provided criteria. A first resonator length is defined between the output mirror and the first mirror, while a second resonator length is defined between the output mirror and the second mirror. The second resonator length is a function of the first resonator length.
Quasi-distributed fiber sensor using active mode locking laser cavity with multiple FBG reflections
NASA Astrophysics Data System (ADS)
Park, Chang Hyun; Kim, Gyeong Hun; Kim, Chang-Seok; Lee, Hwi Don; Chung, Youngjoo
2017-04-01
We have demonstrated a quasi-distributed sensor using an active mode-locking (AML) laser with multiple fiber Bragg grating (FBG) reflections of the same center wavelength. We found that variations in the multiple cavity segment lengths between FBGs can be measured by simply sweeping the modulation frequency, because the modulation frequency of the AML laser is proportionally affected by cavity length.
Lamp method and apparatus using multiple reflections
MacLennan, D.A.; Turner, B.; Kipling, K.
1999-05-11
A method wherein the light in a sulfur or selenium lamp is reflected through the fill a multiplicity of times to convert ultraviolet radiation to visible is disclosed. A light emitting device comprised of an electrodeless envelope which bears a light reflecting covering around a first portion which does not crack due to differential thermal expansion and which has a second portion which comprises a light transmissive aperture. 20 figs.
Federal Register 2010, 2011, 2012, 2013, 2014
2012-02-27
... particular area if they believe that the present limit does not accurately reflect the higher sales prices in that area. Any request for an increase must be accompanied by sufficient housing sales price data to justify higher limits. Typically, this data includes housing sales data extracted from multiple listing...
Write Now! Using Reflective Writing beyond the Humanities and Social Sciences
ERIC Educational Resources Information Center
Cannady, Rachel E.; Gallo, Kasia Z.
2016-01-01
Writing is an important teaching and learning tool that fosters active and critical thinking. There are multiple pressures for disciplines outside the humanities and social sciences to integrate writing in their courses. The shift from teaching solely discipline-specific skills to including writing in a meaningful way can be a daunting process. An…
NASA Technical Reports Server (NTRS)
1978-01-01
Development of systems for obtaining radiation budget and cloud data is discussed. Instruments for measuring total solar irradiance, total infrared flux, reflected solar flux, and cloud heights and properties are considered. Other topics discussed include sampling by multiple satellites, user identification, and determination of the parameters that need to be measured.
ERIC Educational Resources Information Center
Hu, Ran; Smith, Judith J.
2011-01-01
In this collaborative self-study, two first-year assistant professors examine their views of teaching and learning from two cultural perspectives. Drawing from multiple data sources, including reflective analyses of teaching, monthly peer-support meetings, and the Students Opinion Information Survey, the study explores the differences in views of…
ERIC Educational Resources Information Center
Mihai, Alina; Butera, Gretchen; Friesen, Amber
2017-01-01
Research Findings: This qualitative study examined how Head Start teachers thought about children's early literacy and how they enacted their thinking in a year-long curriculum reform effort. Data collected included interviews, observations, questionnaires, concept maps, and teachers' reflections on implementation. The results indicated that as…
Teaching Human Rights in Turkey: Commentaries on a Single Lesson from Multiple Perspectives
ERIC Educational Resources Information Center
Kesten, Alper; Schur, Joan Brodsky; Gürsoy, Kudret
2014-01-01
This group of commentaries on teaching human rights in Turkey includes: (1) Reflection on Turkish Human Rights Lesson from Turkey (Alper Kesten)--A lesson on human rights in Turkey is analyzed for its representativity and methodology within the Turkish teaching culture from the viewpoint of a Turkish researcher; (2) Commentary on a Turkish Lesson…
Valdés, Pablo A.; Kim, Anthony; Leblond, Frederic; Conde, Olga M.; Harris, Brent T.; Paulsen, Keith D.; Wilson, Brian C.; Roberts, David W.
2011-01-01
Biomarkers are indicators of biological processes and hold promise for the diagnosis and treatment of disease. Gliomas represent a heterogeneous group of brain tumors with marked intra- and inter-tumor variability. The extent of surgical resection is a significant factor influencing post-surgical recurrence and prognosis. Here, we used fluorescence and reflectance spectral signatures for in vivo quantification of multiple biomarkers during glioma surgery, with fluorescence contrast provided by exogenously-induced protoporphyrin IX (PpIX) following administration of 5-aminolevulinic acid. We performed light-transport modeling to quantify multiple biomarkers indicative of tumor biological processes, including the local concentration of PpIX and associated photoproducts, total hemoglobin concentration, oxygen saturation, and optical scattering parameters. We developed a diagnostic algorithm for intra-operative tissue delineation that accounts for the combined tumor-specific predictive capabilities of these quantitative biomarkers. Tumor tissue delineation achieved accuracies of up to 94% (specificity = 94%, sensitivity = 94%) across a range of glioma histologies beyond current state-of-the-art optical approaches, including state-of-the-art fluorescence image guidance. This multiple biomarker strategy opens the door to optical methods for surgical guidance that use quantification of well-established neoplastic processes. Future work would seek to validate the predictive power of this proof-of-concept study in a separate larger cohort of patients. PMID:22112112
NASA Astrophysics Data System (ADS)
Valdés, Pablo A.; Kim, Anthony; Leblond, Frederic; Conde, Olga M.; Harris, Brent T.; Paulsen, Keith D.; Wilson, Brian C.; Roberts, David W.
2011-11-01
Biomarkers are indicators of biological processes and hold promise for the diagnosis and treatment of disease. Gliomas represent a heterogeneous group of brain tumors with marked intra- and inter-tumor variability. The extent of surgical resection is a significant factor influencing post-surgical recurrence and prognosis. Here, we used fluorescence and reflectance spectral signatures for in vivo quantification of multiple biomarkers during glioma surgery, with fluorescence contrast provided by exogenously-induced protoporphyrin IX (PpIX) following administration of 5-aminolevulinic acid. We performed light-transport modeling to quantify multiple biomarkers indicative of tumor biological processes, including the local concentration of PpIX and associated photoproducts, total hemoglobin concentration, oxygen saturation, and optical scattering parameters. We developed a diagnostic algorithm for intra-operative tissue delineation that accounts for the combined tumor-specific predictive capabilities of these quantitative biomarkers. Tumor tissue delineation achieved accuracies of up to 94% (specificity = 94%, sensitivity = 94%) across a range of glioma histologies beyond current state-of-the-art optical approaches, including state-of-the-art fluorescence image guidance. This multiple biomarker strategy opens the door to optical methods for surgical guidance that use quantification of well-established neoplastic processes. Future work would seek to validate the predictive power of this proof-of-concept study in a separate larger cohort of patients.
System and technique for characterizing fluids using ultrasonic diffraction grating spectroscopy
Greenwood, Margaret S.
2005-04-12
A system for determining a property of a fluid based on ultrasonic diffraction grating spectroscopy includes a diffraction grating on a solid in contact with the fluid. An interrogation device delivers ultrasound through the solid and a captures a reflection spectrum from the diffraction grating. The reflection spectrum including a diffraction order equal to zero exhibits a peak whose location is used to determine speed of sound in the fluid. A separate measurement of the acoustic impedance is combined with the determined speed of sound to yield a measure of fluid density. A system for determining acoustic impedance includes an ultrasonic transducer on a first surface of a solid member, and an opposed second surface of the member is in contact with a fluid to be monitored. A longitudinal ultrasonic pulse is delivered through the solid member, and a multiplicity of pulse echoes caused by reflections of the ultrasonic pulse between the solid-fluid interface and the transducer-solid interface are detected. The decay rate of the detected echo amplitude as a function of echo number is used to determine acoustic impedance.
Slotnick, Scott D
2017-07-01
Analysis of functional magnetic resonance imaging (fMRI) data typically involves over one hundred thousand independent statistical tests; therefore, it is necessary to correct for multiple comparisons to control familywise error. In a recent paper, Eklund, Nichols, and Knutsson used resting-state fMRI data to evaluate commonly employed methods to correct for multiple comparisons and reported unacceptable rates of familywise error. Eklund et al.'s analysis was based on the assumption that resting-state fMRI data reflect null data; however, their 'null data' actually reflected default network activity that inflated familywise error. As such, Eklund et al.'s results provide no basis to question the validity of the thousands of published fMRI studies that have corrected for multiple comparisons or the commonly employed methods to correct for multiple comparisons.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Myers, Tanya L.; Tonkyn, Russell G.; Danby, Tyler O.
For optical modeling and other purposes, we have created a library of 57 liquids for which we have measured the complex optical constants n and k. These liquids vary in their nature, ranging in properties including chemical structure, optical band strength, volatility and viscosity. By obtaining the optical constants one can in principle model most optical phenomena in media and at interfaces including reflection, refraction and dispersion. Based on the original methods of J.E. Bertie et al.1 [1Bert1], we have developed improved protocols using multiple path lengths to determine the optical constants n/k for dozens of liquids, including inorganic, organicmore » and organophosphorus compounds. Detailed descriptions of the measurement and data reduction protocols are discussed; agreement of the derived optical constant n and k values with literature values are presented. We also present results using the n/k values as applied to an optical modeling scenario whereby the derived data are presented and tested for models of 1 µm and 100 µm layers for DMMP (dimethyl methyl phosphonate) on both metal (aluminum) and dielectric (soda lime glass) substrates to show substantial differences between the reflected signal from highly reflective substrates and less-reflective substrates.« less
Influence of multiple scattering on CloudSat measurements in snow: A model study
NASA Astrophysics Data System (ADS)
Matrosov, Sergey Y.; Battaglia, Alessandro
2009-06-01
The effects of multiple scattering on larger precipitating hydrometers have an influence on measurements of the spaceborne W-band (94 GHz) CloudSat radar. This study presents initial quantitative estimates of these effects in “dry” snow using radiative transfer calculations for appropriate snowfall models. It is shown that these effects become significant (i.e., greater than approximately 1 dB) when snowfall radar reflectivity factors are greater than about 10-15 dBZ. Reflectivity enhancement due to multiple scattering can reach 4-5 dB in heavier stratiform snowfalls. Multiple scattering effects counteract signal attenuation, so the observed CloudSat reflectivity factors in snowfall could be relatively close to the values that would be observed in the case of single scattering and the absence of attenuation.
General theory of remote gaze estimation using the pupil center and corneal reflections.
Guestrin, Elias Daniel; Eizenman, Moshe
2006-06-01
This paper presents a general theory for the remote estimation of the point-of-gaze (POG) from the coordinates of the centers of the pupil and corneal reflections. Corneal reflections are produced by light sources that illuminate the eye and the centers of the pupil and corneal reflections are estimated in video images from one or more cameras. The general theory covers the full range of possible system configurations. Using one camera and one light source, the POG can be estimated only if the head is completely stationary. Using one camera and multiple light sources, the POG can be estimated with free head movements, following the completion of a multiple-point calibration procedure. When multiple cameras and multiple light sources are used, the POG can be estimated following a simple one-point calibration procedure. Experimental and simulation results suggest that the main sources of gaze estimation errors are the discrepancy between the shape of real corneas and the spherical corneal shape assumed in the general theory, and the noise in the estimation of the centers of the pupil and corneal reflections. A detailed example of a system that uses the general theory to estimate the POG on a computer screen is presented.
Specialized Color Targets for Spectral Reflectance Reconstruction of Magnified Images
NASA Astrophysics Data System (ADS)
Kruschwitz, Jennifer D. T.
Digital images are used almost exclusively instead of film to capture visual information across many scientific fields. The colorimetric color representation within these digital images can be relayed from the digital counts produced by the camera with the use of a known color target. In image capture of magnified images, there is currently no reliable color target that can be used at multiple magnifications and give the user a solid understanding of the color ground truth within those images. The first part of this dissertation included the design, fabrication, and testing of a color target produced with optical interference coated microlenses for use in an off-axis illumination, compound microscope. An ideal target was designed to increase the color gamut for colorimetric imaging and provide the necessary "Block Dye" spectral reflectance profiles across the visible spectrum to reduce the number of color patches necessary for multiple filter imaging systems that rely on statistical models for spectral reflectance reconstruction. There are other scientific disciplines that can benefit from a specialized color target to determine the color ground truth in their magnified images and perform spectral estimation. Not every discipline has the luxury of having a multi-filter imaging system. The second part of this dissertation developed two unique ways of using an interference coated color mirror target: one that relies on multiple light-source angles, and one that leverages a dynamic color change with time. The source multi-angle technique would be used for the microelectronic discipline where the reconstructed spectral reflectance would be used to determine a dielectric film thickness on a silicon substrate, and the time varying technique would be used for a biomedical example to determine the thickness of human tear film.
Angular distribution of diffuse reflectance from incoherent multiple scattering in turbid media.
Gao, M; Huang, X; Yang, P; Kattawar, G W
2013-08-20
The angular distribution of diffuse reflection is elucidated with greater understanding by studying a homogeneous turbid medium. We modeled the medium as an infinite slab and studied the reflection dependence on the following three parameters: the incident direction, optical depth, and asymmetry factor. The diffuse reflection is produced by incoherent multiple scattering and is solved through radiative transfer theory. At large optical depths, the angular distribution of the diffuse reflection with small incident angles is similar to that of a Lambertian surface, but, with incident angles larger than 60°, the angular distributions have a prominent reflection peak around the specular reflection angle. These reflection peaks are found originating from the scattering within one transport mean free path in the top layer of the medium. The maximum reflection angles for different incident angles are analyzed and can characterize the structure of angular distributions for different asymmetry factors and optical depths. The properties of the angular distribution can be applied to more complex systems for a better understanding of diffuse reflection.
Hackley, Paul C.; Ryder, Robert T.; Trippi, Michael H.; Alimi, Hossein
2013-01-01
To better estimate thermal maturity of Devonian shales in the northern Appalachian Basin, eleven samples of Marcellus and Huron Shale were characterized via multiple analytical techniques. Vitrinite reflectance, Rock–Eval pyrolysis, gas chromatography (GC) of whole rock extracts, and GC–mass spectrometry (GCMS) of extract saturate fractions were evaluated on three transects that lie across previously documented regional thermal maturity isolines. Results from vitrinite reflectance suggest that most samples are immature with respect to hydrocarbon generation. However, bulk geochemical data and sterane and terpane biomarker ratios from GCMS suggest that almost all samples are in the oil window. This observation is consistent with the presence of thermogenic gas in the study area and higher vitrinite reflectance values recorded from overlying Pennsylvanian coals. These results suggest that vitrinite reflectance is a poor predictor of thermal maturity in early mature areas of Devonian shale, perhaps because reported measurements often include determinations of solid bitumen reflectance. Vitrinite reflectance interpretations in areas of early mature Devonian shale should be supplanted by evaluation of thermal maturity information from biomarker ratios and bulk geochemical data.
NASA Technical Reports Server (NTRS)
Davis, Don D , Jr; Stokes, George M; Moore, Dewey; Stevens, George L , Jr
1954-01-01
Equations are presented for the attenuation characteristics of single-chamber and multiple-chamber mufflers of both the expansion-chamber and resonator types, for tuned side-branch tubes, and for the combination of an expansion chamber with a resonator. Experimental curves of attenuation plotted against frequency are presented for 77 different mufflers with a reflection-free tailpipe termination. The experiments were made at room temperature without flow; the sound source was a loud-speaker. A method is given for including the tailpipe reflections in the calculations. Experimental attenuation curves are presented for four different muffler-tailpipe combinations, and the results are compared with the theory. The application of the theory to the design of engine-exhaust mufflers is discussed, and charts are included for the assistance of the designer.
Limitations of quantitative analysis of deep crustal seismic reflection data: Examples from GLIMPCE
Lee, Myung W.; Hutchinson, Deborah R.
1992-01-01
Amplitude preservation in seismic reflection data can be obtained by a relative true amplitude (RTA) processing technique in which the relative strength of reflection amplitudes is preserved vertically as well as horizontally, after compensating for amplitude distortion by near-surface effects and propagation effects. Quantitative analysis of relative true amplitudes of the Great Lakes International Multidisciplinary Program on Crustal Evolution seismic data is hampered by large uncertainties in estimates of the water bottom reflection coefficient and the vertical amplitude correction and by inadequate noise suppression. Processing techniques such as deconvolution, F-K filtering, and migration significantly change the overall shape of amplitude curves and hence calculation of reflection coefficients and average reflectance. Thus lithological interpretation of deep crustal seismic data based on the absolute value of estimated reflection strength alone is meaningless. The relative strength of individual events, however, is preserved on curves generated at different stages in the processing. We suggest that qualitative comparisons of relative strength, if used carefully, provide a meaningful measure of variations in reflectivity. Simple theoretical models indicate that peg-leg multiples rather than water bottom multiples are the most severe source of noise contamination. These multiples are extremely difficult to remove when the water bottom reflection coefficient is large (>0.6), a condition that exists beneath parts of Lake Superior and most of Lake Huron.
Analysis of multiple internal reflections in a parallel aligned liquid crystal on silicon SLM.
Martínez, José Luis; Moreno, Ignacio; del Mar Sánchez-López, María; Vargas, Asticio; García-Martínez, Pascuala
2014-10-20
Multiple internal reflection effects on the optical modulation of a commercial reflective parallel-aligned liquid-crystal on silicon (PAL-LCoS) spatial light modulator (SLM) are analyzed. The display is illuminated with different wavelengths and different angles of incidence. Non-negligible Fabry-Perot (FP) effect is observed due to the sandwiched LC layer structure. A simplified physical model that quantitatively accounts for the observed phenomena is proposed. It is shown how the expected pure phase modulation response is substantially modified in the following aspects: 1) a coupled amplitude modulation, 2) a non-linear behavior of the phase modulation, 3) some amount of unmodulated light, and 4) a reduction of the effective phase modulation as the angle of incidence increases. Finally, it is shown that multiple reflections can be useful since the effect of a displayed diffraction grating is doubled on a beam that is reflected twice through the LC layer, thus rendering gratings with doubled phase modulation depth.
Wang, Shinn-Fwu; Chiu, Ming-Hung; Chen, Wei-Wu; Kao, Fu-Hsi; Chang, Rong-Seng
2009-05-01
A small-displacement sensing system based on multiple total internal reflections in heterodyne interferometry is proposed. In this paper, a small displacement can be obtained only by measuring the variation in phase difference between s- and p-polarization states for the total internal reflection effect. In order to improve the sensitivity, we increase the number of total internal reflections by using a parallelogram prism. The theoretical resolution of the method is better than 0.417 nm. The method has some merits, e.g., high resolution, high sensitivity, and real-time measurement. Also, its feasibility is demonstrated.
Initiation of Detonation in Multiple Shock-Compressed Liquid Explosives
NASA Astrophysics Data System (ADS)
Yoshinaka, A. C.; Zhang, F.; Petel, O. E.; Higgins, A. J.
2006-07-01
Initiation and resulting propagation of detonation via multiple shock reverberations between two high impedance plates has been investigated in amine-sensitized nitromethane. Experiments were designed so that the first reflected shock strength was below the critical value for initiation found previously. Luminosity combined with a distinct pressure hump indicated onset of reaction and successful initiation after double or triple shock reflection off the bottom plate. Final temperature estimates for double or triple shock reflection immediately before initiation lie between 700-720 K, consistent with those found previously for both incident and singly reflected shock initiation.
Using Relationships to Heal Trauma: Reflective Practices Creates a Therapeutic Preschool
ERIC Educational Resources Information Center
Brinamen, Charles; Page, Farris
2012-01-01
More than 20 percent of children (ages 2-17) in the United States have witnessed and/or been victims of multiple forms of violence. Children from birth through age 5 are more likely to experience maltreatment and neglect than other age groups. Violence and trauma (including neglect), whether in the home or the community, have lasting effects on…
ERIC Educational Resources Information Center
Novosel, Leslie C.
2012-01-01
Employing multiple methods, including a comparison group pre/posttest design and student interviews and self-reflections, this study represents an initial attempt to investigate the efficacy of a social and emotional learning self-regulation strategy relative to the general reading ability, reading self-concept, and social and emotional well-being…
Cardiac function in muscular dystrophy associates with abdominal muscle pathology.
Gardner, Brandon B; Swaggart, Kayleigh A; Kim, Gene; Watson, Sydeaka; McNally, Elizabeth M
The muscular dystrophies target muscle groups differentially. In mouse models of muscular dystrophy, notably the mdx model of Duchenne Muscular Dystrophy, the diaphragm muscle shows marked fibrosis and at an earlier age than other muscle groups, more reflective of the histopathology seen in human muscular dystrophy. Using a mouse model of limb girdle muscular dystrophy, the Sgcg mouse, we compared muscle pathology across different muscle groups and heart. A cohort of nearly 200 Sgcg mice were studied using multiple measures of pathology including echocardiography, Evans blue dye uptake and hydroxyproline content in multiple muscle groups. Spearman rank correlations were determined among echocardiographic and pathological parameters. The abdominal muscles were found to have more fibrosis than other muscle groups, including the diaphragm muscle. The abdominal muscles also had more Evans blue dye uptake than other muscle groups. The amount of diaphragm fibrosis was found to correlate positively with fibrosis in the left ventricle, and abdominal muscle fibrosis correlated with impaired left ventricular function. Fibrosis in the abdominal muscles negatively correlated with fibrosis in the diaphragm and right ventricles. Together these data reflect the recruitment of abdominal muscles as respiratory muscles in muscular dystrophy, a finding consistent with data from human patients.
Important ingredients for health adaptive information systems.
Senathirajah, Yalini; Bakken, Suzanne
2011-01-01
Healthcare information systems frequently do not truly meet clinician needs, due to the complexity, variability, and rapid change in medical contexts. Recently the internet world has been transformed by approaches commonly termed 'Web 2.0'. This paper proposes a Web 2.0 model for a healthcare adaptive architecture. The vision includes creating modular, user-composable systems which aim to make all necessary information from multiple internal and external sources available via a platform, for the user to use, arrange, recombine, author, and share at will, using rich interfaces where advisable. Clinicians can create a set of 'widgets' and 'views' which can transform data, reflect their domain knowledge and cater to their needs, using simple drag and drop interfaces without the intervention of programmers. We have built an example system, MedWISE, embodying the user-facing parts of the model. This approach to HIS is expected to have several advantages, including greater suitability to user needs (reflecting clinician rather than programmer concepts and priorities), incorporation of multiple information sources, agile reconfiguration to meet emerging situations and new treatment deployment, capture of user domain expertise and tacit knowledge, efficiencies due to workflow and human-computer interaction improvements, and greater user acceptance.
Dickel, Timo; Plaß, Wolfgang R; Lippert, Wayne; Lang, Johannes; Yavor, Mikhail I; Geissel, Hans; Scheidenberger, Christoph
2017-06-01
A novel method for (ultra-)high-resolution spatial mass separation in time-of-flight mass spectrometers is presented. Ions are injected into a time-of-flight analyzer from a radio frequency (rf) trap, dispersed in time-of-flight according to their mass-to-charge ratios and then re-trapped dynamically in the same rf trap. This re-trapping technique is highly mass-selective and after sufficiently long flight times can provide even isobaric separation. A theoretical treatment of the method is presented and the conditions for optimum performance of the method are derived. The method has been implemented in a multiple-reflection time-of-flight mass spectrometer and mass separation powers (FWHM) in excess of 70,000, and re-trapping efficiencies of up to 35% have been obtained for the protonated molecular ion of caffeine. The isobars glutamine and lysine (relative mass difference of 1/4000) have been separated after a flight time of 0.2 ms only. Higher mass separation powers can be achieved using longer flight times. The method will have important applications, including isobar separation in nuclear physics and (ultra-)high-resolution precursor ion selection in multiple-stage tandem mass spectrometry. Graphical Abstract ᅟ.
NASA Astrophysics Data System (ADS)
Dickel, Timo; Plaß, Wolfgang R.; Lippert, Wayne; Lang, Johannes; Yavor, Mikhail I.; Geissel, Hans; Scheidenberger, Christoph
2017-06-01
A novel method for (ultra-)high-resolution spatial mass separation in time-of-flight mass spectrometers is presented. Ions are injected into a time-of-flight analyzer from a radio frequency (rf) trap, dispersed in time-of-flight according to their mass-to-charge ratios and then re-trapped dynamically in the same rf trap. This re-trapping technique is highly mass-selective and after sufficiently long flight times can provide even isobaric separation. A theoretical treatment of the method is presented and the conditions for optimum performance of the method are derived. The method has been implemented in a multiple-reflection time-of-flight mass spectrometer and mass separation powers (FWHM) in excess of 70,000, and re-trapping efficiencies of up to 35% have been obtained for the protonated molecular ion of caffeine. The isobars glutamine and lysine (relative mass difference of 1/4000) have been separated after a flight time of 0.2 ms only. Higher mass separation powers can be achieved using longer flight times. The method will have important applications, including isobar separation in nuclear physics and (ultra-)high-resolution precursor ion selection in multiple-stage tandem mass spectrometry. [Figure not available: see fulltext.
Reflective Coating for Lightweight X-Ray Optics
NASA Technical Reports Server (NTRS)
Chan, Kai-Wing; Zhang, William W.; Windt, David; Hong, Mao-Ling; Saha, Timo; McClelland, Ryan; Sharpe, Marton; Dwivedi, Vivek H.
2012-01-01
X-ray reflective coating for next generation's lightweight, high resolution, optics for astronomy requires thin-film deposition that is precisely fine-tuned so that it will not distort the thin sub-mm substrates. Film of very low stress is required. Alternatively, mirror distortion can be cancelled by precisely balancing the deformation from multiple films. We will present results on metallic film deposition for the lightweight optics under development. These efforts include: low-stress deposition by magnetron sputtering and atomic layer deposition of the metals, balancing of gross deformation with two-layer depositions of opposite stresses and with depositions on both sides of the thin mirrors.
Peculiarities of section topograms for the multiple diffraction of X rays
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kohn, V. G., E-mail: kohnvict@yandex.ru; Smirnova, I. A.
The distortion of interference fringes on the section topograms of single crystal due to the multiple diffraction of X rays has been investigated. The cases of the 220 and 400 reflections in a silicon crystal in the form of a plate with a surface oriented normally to the [001] direction are considered both theoretically and experimentally. The same section topogram exhibits five cases of multiple diffraction at small azimuthal angles for the 400 reflection and MoK{sub α} radiation, while the topogram for the 220 reflection demonstrates two cases of multiple diffraction. All these cases correspond to different combinations of reciprocalmore » lattice vectors. Exact theoretical calculations of section topograms for the aforementioned cases of multiple diffraction have been performed for the first time. The section topograms exhibit two different distortion regions. The distortions in the central region of the structure are fairly complex and depend strongly on the azimuthal angle. In the tails of the multiple diffraction region, there is a shift of two-beam interference fringes, which can be observed even with a laboratory X-ray source.« less
Translating Theory Into Practice: Implementing a Program of Assessment.
Hauer, Karen E; O'Sullivan, Patricia S; Fitzhenry, Kristen; Boscardin, Christy
2018-03-01
A program of assessment addresses challenges in learner assessment using a centrally planned, coordinated approach that emphasizes assessment for learning. This report describes the steps taken to implement a program of assessment framework within a medical school. A literature review on best practices in assessment highlighted six principles that guided implementation of the program of assessment in 2016-2017: (1) a centrally coordinated plan for assessment aligns with and supports a curricular vision; (2) multiple assessment tools used longitudinally generate multiple data points; (3) learners require ready access to information-rich feedback to promote reflection and informed self-assessment; (4) mentoring is essential to facilitate effective data use for reflection and learning planning; (5) the program of assessment fosters self-regulated learning behaviors; and (6) expert groups make summative decisions about grades and readiness for advancement. Implementation incorporated stakeholder engagement, use of multiple assessment tools, design of a coaching program, and creation of a learner performance dashboard. The assessment team monitors adherence to principles defining the program of assessment and gathers and responds to regular feedback from key stakeholders, including faculty, staff, and students. Next steps include systematically collecting evidence for validity of individual assessments and the program overall. Iterative review of student performance data informs curricular improvements. The program of assessment also highlights technology needs that will be addressed with information technology experts. The outcome ultimately will entail showing evidence of validity that the program produces physicians who engage in lifelong learning and provide high-quality patient care.
Observation of multiple superconducting gaps in Fe1+y Se x Te 1-x through Andreev reflection
NASA Astrophysics Data System (ADS)
de, Debtanu; Diaz-Pinto, Carlos; Wu, Zheng; Hor, Pei-Herng; Peng, Haibing
2011-03-01
Iron-based superconductors have been under intensive study because of the high transition temperature and the intriguing physical mechanisms involving the superconductivity and magnetic orders. Theoretical studies on the role of spin fluctuation suggest unconventional S wave pairing and multiple superconducting (SC) gaps due to the five disjoint Fermi surfaces. However, this multiple SC-gap scenario has yet to be confirmed in experiments. Here we report the experimental observation of five SC gaps in Fe 1+y Se x Te 1-x from Andreev reflection spectra, along with negative differential conductance dips due to the pair breaking related to the largest SC gap. The evolution of the multiple SC gaps is further investigated as a function of both temperature and magnetic field. For the largest SC gap, the Andreev reflection signal persists above bulk Tc, suggesting the existence of phase incoherent Cooper pairs.
Earpiece with sensors to measure/monitor multiple physiological variables
NASA Technical Reports Server (NTRS)
Cooper, Tommy G. (Inventor); Schulze, Arthur E. (Inventor)
2003-01-01
An apparatus and method for positioning sensors relative to one another and anatomic features in a non-invasive device for measuring and monitoring multiple physiological variables from a single site uses an earpiece incorporating a shielded pulse oximetry sensor (POS) having a miniaturized set of LEDs and photosensors configured for pulse oximetry measurements in the reflectance mode and located in the earpiece so as to position the POS against a rear wall of an ear canal. The earpiece also includes a thermopile of no larger than 7 mm. in diameter located on the earpiece to so as to position the thermopile past a second turn of an external auditory meatus so as to view the tympanic membrane. The thermopile includes a reference temperature sensor attached to its base for ambient temperature compensation.
Optical Anisotropy of Photonic Crystals of Cubic Symmetry Induced by Multiple Diffraction of Light
NASA Astrophysics Data System (ADS)
Ukleev, T. A.; Shevchenko, N. N.; Iurasova, D. I.; Sel'kin, A. V.
2018-05-01
The optical spectra of Bragg reflection from opal-like photonic crystals under conditions of the resonant enhancement of the multiple diffraction of light have been studied experimentally and theoretically using the photonic crystal structures prepared of monodisperse polystyrene globules. It is shown that the reflection signal registered in mutually orthogonal configurations of the polarizer and analyzer is related to the intrinsic optical anisotropy of the crystals and is a specific manifestation of the multiple Bragg diffraction in three-dimensional photonic crystals.
ERIC Educational Resources Information Center
Gonzalez, Monica M.
2017-01-01
English Language Learners (ELLs) are students who speak a language other than English; they are the fastest growing student population in United States' (US) public schools and will include over 17 million students by the year 2020 (NCES,2015). The dramatic increase in the ELL student population means that all mainstream classroom teachers will…
ERIC Educational Resources Information Center
Zutell, Jerry, Ed.; McCormick, Sandra, Ed.
Reflecting diversified views, this National Reading Conference yearbook contains 45 articles in the field of literacy theory and research. Articles and their authors include: "The Myth of Teaching" (J. V. Hoffman); "Reading-Writing Connections: The Relations among Three Perspectives" (T. Shanahan and R. J. Tierney);…
Plasmonic Metallurgy Enabled by DNA
Ross, Michael B.; Ku, Jessie C.; Lee, Byeongdu; ...
2016-02-05
In this study, mixed silver and gold plasmonic nanoparticle architectures are synthesized using DNA-programmable assembly, unveiling exquisitely tunable optical properties that are predicted and explained both by effective thin-film models and explicit electrodynamic simulations. These data demonstrate that the manner and ratio with which multiple metallic components are arranged can greatly alter optical properties, including tunable color and asymmetric reflectivity behavior of relevance for thin-film applications.
Introduction to Communication Systems
2014-01-17
channel modeling in complex baseband using ray tracing, reinforced by a software lab which applies these ideas to simulate link time variations for a...analog acoustic signal is generated (often translated to an analog electrical signal using a microphone). Even when this music is recorded onto a...include line of sight (LOS) and reflected paths. Equation (2.35) immediately tells us how to model multipath channels, in which multiple scat- tered
Character of the opposition effect and negative polarization
NASA Technical Reports Server (NTRS)
Pieters, Carle M.; Shkuratov, Yu. G.; Stankevich, D. G.
1991-01-01
Photometric and polarimetric properties at small phase angles were measured for silicates with controlled surface properties in order to distinguish properties that are associated with surface reflection from those that are associated with multiple scattering from internal grain boundaries. These data provide insight into the causes and conditions of photometric properties observed at small phase angles for dark bodies of the solar system. Obsidian was chosen to represent a silicate dielectric with no internal scattering boundaries. Because obsidian is free of internal scatterers, light reflected from both the rough and smooth obsidian samples is almost entirely single and multiple Fresnel reflections form surface facets with no body component. Surface structure alone cannot produce an opposition effect. Comparison of the obsidian and basalt results indicates that for an opposition effect to occur, surface texture must be both rough and contain internal scattering interfaces. Although the negative polarization observed for the obsidian samples indicates single and multiple reflections are part of negative polarization, the longer inversion angle of the multigrain inversion samples implies that internal reflections must also contribute a significant negative polarization component.
Atmospheric and Science Complexity Effects on Surface Bidirectional Reflectance
NASA Technical Reports Server (NTRS)
Diner, D. J. (Principal Investigator); Martonchik, J. V.; Sythe, W. D.; Hessom, C.
1985-01-01
Among the tools used in passive remote sensing of Earth resources in the visible and near-infrared spectral regions are measurements of spectral signature and bidirectional reflectance functions (BDRFs). Determination of surface properties using these observables is complicated by a number of factors, including: (1) mixing of surface components, such as soil and vegetation, (2) multiple reflections of radiation due to complex geometry, such as in crop canopies, and (3) atmospheric effects. In order to bridge the diversity in these different approaches, there is a need for a fundamental physical understanding of the influence of the various effects and a quantiative measure of their relative importance. In particular, we consider scene complexity effects using the example of reflection by vegetative surfaces. The interaction of sunlight with a crop canopy and interpretation of the spectral and angular dependence of the emergent radiation is basically a multidimensional radiative transfer problem. The complex canopy geometry, underlying soil cover, and presence of diffuse as well as collimated illumination will modify the reflectance characteristics of the canopy relative to those of the individual elements.
Holographic Solar Photon Thrusters
NASA Technical Reports Server (NTRS)
Johnson, Les; Matloff, Greg
2006-01-01
A document discusses a proposal to incorporate holographic optical elements into solar photon thrusters (SPTs). First suggested in 1990, SPTs would be systems of multiple reflective, emissive, and absorptive surfaces (solar sails) that would be attached to spacecraft orbiting the Earth to derive small propulsive forces from radiation pressures. An SPT according to the proposal would include, among other things, a main sail. One side of the sail would be highly emissive and would normally face away from the Earth. The other side would be reflective and would be covered by white-light holographic images that would alternately become reflective, transmissive, and absorptive with small changes in the viewing angle. When the spacecraft was at a favorable orbital position, the main sail would be oriented to reflect sunlight in a direction to maximize the solar thrust; when not in a favorable position, the main sail would be oriented to present a substantially absorptive/emissive aspect to minimize the solar drag. By turning the main sail slightly to alternate between the reflective and absorptive/ emissive extremes, one could achieve nearly a doubling or halving of the radiational momentum transfer and, hence, of the solar thrust.
Pediatric Multiple Sclerosis: Genes, Environment, and a Comprehensive Therapeutic Approach.
Cappa, Ryan; Theroux, Liana; Brenton, J Nicholas
2017-10-01
Pediatric multiple sclerosis is an increasingly recognized and studied disorder that accounts for 3% to 10% of all patients with multiple sclerosis. The risk for pediatric multiple sclerosis is thought to reflect a complex interplay between environmental and genetic risk factors. Environmental exposures, including sunlight (ultraviolet radiation, vitamin D levels), infections (Epstein-Barr virus), passive smoking, and obesity, have been identified as potential risk factors in youth. Genetic predisposition contributes to the risk of multiple sclerosis, and the major histocompatibility complex on chromosome 6 makes the single largest contribution to susceptibility to multiple sclerosis. With the use of large-scale genome-wide association studies, other non-major histocompatibility complex alleles have been identified as independent risk factors for the disease. The bridge between environment and genes likely lies in the study of epigenetic processes, which are environmentally-influenced mechanisms through which gene expression may be modified. This article will review these topics to provide a framework for discussion of a comprehensive approach to counseling and ultimately treating the pediatric patient with multiple sclerosis. Copyright © 2017 Elsevier Inc. All rights reserved.
Complexities of management of a urostomy in Ehlers-Danlos syndrome: a reflective account.
Oxenham, Julie
Mary (pseudonym) is a 30-year-old woman who underwent a urinary diversion and formation of an ileal conduit/urostomy (urinary stoma) due to the formation of multiple bladder diverticula, which caused micturition difficulties and recurrent urinary tract infections with associated pain and discomfort. The bladder diverticula were caused by Ehlers-Danlos syndrome (EDS), a hereditary disorder of the connective tissue or, particulary, defective collagen. Surgical intervention in patients with EDS is prone to complications due to poor wound healing, including issues of dehiscence, postoperative bleeding and poor uptake of anaesthesia and analgesia. After an initial presentation of the syndrome of EDS and Mary's history, this article offers a reflective account (informed by Gibbs' Reflective Cycle) and illustrates the complexities of caring for an individual with EDS who undergoes stoma formation. The author, a stoma care nurse, demonstrates how using purposeful reflection resulted in better understanding and awareness of caring for an individual with a rare syndrome and the nursing challenges this presented.
Aggression at Age 5 as a Function of Prenatal Exposure to Cocaine, Gender, and Environmental Risk
Bendersky, Margaret; Bennett, David; Lewis, Michael
2006-01-01
Objective To examine childhood aggression at age 5 in a multiple risk model that includes cocaine exposure, environmental risk, and gender as predictors. Methods Aggression was assessed in 206 children by using multiple methods including teacher report, parent report, child’s response to hypothetical provocations, and child’s observed behavior. Also examined was a composite score that reflected high aggression across contexts. Results Multiple regression analyses indicated that a significant amount of variance in each of the aggression measures and the composite was explained by the predictors. The variables that were independently related differed depending on the outcome. Cocaine exposure, gender, and environmental risk were all related to the composite aggression score. Conclusions Cocaine exposure, being male, and a high-risk environment were all predictive of aggressive behavior at 5 years. It is this group of exposed boys at high environmental risk that is most likely to show continued aggression over time. PMID:15827351
Non-destructive testing of full-length bonded rock bolts based on HHT signal analysis
NASA Astrophysics Data System (ADS)
Shi, Z. M.; Liu, L.; Peng, M.; Liu, C. C.; Tao, F. J.; Liu, C. S.
2018-04-01
Full-length bonded rock bolts are commonly used in mining, tunneling and slope engineering because of their simple design and resistance to corrosion. However, the length of a rock bolt and grouting quality do not often meet the required design standards in practice because of the concealment and complexity of bolt construction. Non-destructive testing is preferred when testing a rock bolt's quality because of the convenience, low cost and wide detection range. In this paper, a signal analysis method for the non-destructive sound wave testing of full-length bonded rock bolts is presented, which is based on the Hilbert-Huang transform (HHT). First, we introduce the HHT analysis method to calculate the bolt length and identify defect locations based on sound wave reflection test signals, which includes decomposing the test signal via empirical mode decomposition (EMD), selecting the intrinsic mode functions (IMF) using the Pearson Correlation Index (PCI) and calculating the instantaneous phase and frequency via the Hilbert transform (HT). Second, six model tests are conducted using different grouting defects and bolt protruding lengths to verify the effectiveness of the HHT analysis method. Lastly, the influence of the bolt protruding length on the test signal, identification of multiple reflections from defects, bolt end and protruding end, and mode mixing from EMD are discussed. The HHT analysis method can identify the bolt length and grouting defect locations from signals that contain noise at multiple reflected interfaces. The reflection from the long protruding end creates an irregular test signal with many frequency peaks on the spectrum. The reflections from defects barely change the original signal because they are low energy, which cannot be adequately resolved using existing methods. The HHT analysis method can identify reflections from the long protruding end of the bolt and multiple reflections from grouting defects based on mutations in the instantaneous frequency, which makes weak reflections more noticeable. The mode mixing phenomenon is observed in several tests, but this does not markedly affect the identification results due to the simple medium in bolt tests. The mode mixing can be reduced by ensemble EMD (EEMD) or complete ensemble EMD with adaptive noise (CEEMDAN), which are powerful tools to used analyze the test signal in a complex medium and may play an important role in future studies. The HHT bolt signal analysis method is a self-adaptive and automatic process, which can be programed as analysis software and will make bolt tests more convenient in practice.
Backscattering enhancement with a finite beam width for millimeter-wavelength weather radars
NASA Astrophysics Data System (ADS)
Kobayashi, Satoru; Tanelli, Simone; Iguchi, Toshio; Im, Eastwood
2004-12-01
Backscattering enhancement from random hydrometeors should increase as wavelengths of radars reach millimeter regions. For 95 GHz radars, the reflectivity of backscattering is expected to increase by 2 dB, due to multiple scattering including backscattering enhancement, for water droplets of diameter of 1 mm with a density of 5 x 103 m-3. Previous theoretical studies of backscattering enhancement considered infinitely extending plane waves. In this paper, we expand the theory to spherical waves with a Gaussian antenna pattern, including depolarizing effects. While the differences from the plane wave results are not great when the optical thickness is small, as the latter increases the differences become significant, and essentially depend on the ratio of radar footprint radius to the mean free path of hydrometeors. In this regime, for a radar footprint that is smaller than the mean free path, the backscattering-enhancement reflectivity corresponding to spherical waves is significantly less pronounced than in the case of the plane wave theory. Hence this reduction factor must be taken into account when analyzing radar reflectivity factors for use in remote sensing applications.
Teaching and evaluating point of care learning with an Internet-based clinical-question portfolio.
Green, Michael L; Reddy, Siddharta G; Holmboe, Eric
2009-01-01
Diplomates in the American Board of Internal Medicine (ABIM) Maintenance of Certification (MOC) program satisfy the self-evaluation of medical knowledge requirement by completing open-book multiple-choice exams. However, this method remains unlikely to affect practice change and often covers content areas not relevant to diplomates' practices. We developed and evaluated an Internet-based point of care (POC) learning portfolio to serve as an alternative. Participants enter information about their clinical questions, including characteristics, information pursuit, application, and practice change. After documenting 20 questions, they reflect upon a summary report and write commitment-to-change statements about their learning strategies. They can link to help screens and medical information resources. We report on the beta test evaluation of the module, completed by 23 internists and 4 internal medicine residents. Participants found the instructions clear and navigated the module without difficulty. The majority preferred the POC portfolio to multiple-choice examinations, citing greater relevance to their practice, guidance in expanding their palette of information resources, opportunity to reflect on their learning needs, and "credit" for self-directed learning related to their patients. Participants entered a total of 543 clinical questions, of which 250 (46%) resulted in a planned practice change. After completing the module, 14 of 27 (52%) participants committed to at least 1 change in their POC learning strategies. Internists found the portfolio valuable, preferred it to multiple-choice examinations, often changed their practice after pursuing clinical questions, and productively reflected on their learning strategies. The ABIM will offer this portfolio as an elective option in MOC.
Dimaggio, Giancarlo; Lysaker, Paul H; Carcione, Antonino; Nicolò, Giuseppe; Semerari, Antonio
2008-09-01
Social and neurocognitive research suggests that thinking about one's own thinking and thinking about the thinking of others-termed 'mindreading', 'metacognition', 'social cognition' or 'mentalizing' are not identical activities. The ability though to think about thinking in the first person is nevertheless related to the ability to think about other's thoughts in the third person. Unclear is how these phenomena influence one another. In this review, we explore how self-reflection and autobiographical memory influence the capacity to think about the thoughts and emotions of others. We review studies suggesting that the more individuals are able to reflect on and retrieve episodes from their life narratives, the more they are likely to grasp others' thoughts and emotions. We discuss evidence supporting this possibility including studies of the neurocognitive bases of empathy and self-awareness and how different aspects of self-reflection may impact on mindreading. We also draw from clinical reports how improved self-reflection may result in a more nuanced mindreading, namely persons suffering from schizophrenia and narcissistic personality disorder. We finally discuss the implications for research and practice and consider whether there are conditions in which the reverse is true, where self-reflection might impair mindreading or in which mindreading may facilitate self-reflection.
NASA Astrophysics Data System (ADS)
Kilaru, M. K.; Cumby, B.; Heikenfeld, J.
2009-01-01
Corner cube and spherical retroreflectors are ubiquitous in conspicuity and range-finding applications since they reflect light back to the illumination source with unmatched efficiency. We report here a switchable electrowetting retroreflector platform that provides multiple novel features, including (a) using <0.5 μJ/cm2 electrical energy to switch from a light scattering state, (b) low loss and wide spectrum as limited only by the absorption spectrum of water, (c) use of ultrasimple self-assembly of 103-105 liquid lenslets/in.2 on a polymer/Al corner-cube substrate, and (d) change in retroreflected irradiance of >10:1 over a ±30° field of view.
Method of fabricating reflection-mode EUV diffusers
Anderson, Erik; Naulleau, Patrick P.
2005-03-01
Techniques for fabricating well-controlled, random relief, engineered surfaces that serve as substrates for EUV optical devices are accomplished with grayscale exposure. The method of fabricating a multilevel EUV optical element includes: (a) providing a substrate; (b) depositing a layer of curable material on a surface of the substrate; (c) creating a relief profile in a layer of cured material from the layer of curable material wherein the relief profile comprises multiple levels of cured material that has a defined contour; and (d) depositing a multilayer reflection film over the relief profile wherein the film has an outer contour that substantially matches that of the relief profile. The curable material can comprise photoresist or a low dielectric constant material.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Heilbron, Valerie J; Clem, Paul G; Cook, Adam Wade
An illuminated display device with a base member with a plurality of cavities therein. Illumination devices illuminate the cavities and emit light through an opening of the cavities in a pattern, and a speaker can emit sounds in synchronization with the pattern. A panel with translucent portions can overly the base member and the cavities. An animated talking character can have an animated mouth cavity complex with multiple predetermined mouth lighting configurations simulative of human utterances. The cavities can be open, or optical waveguide material or positive members can be disposed therein. Reflective material can enhance internal reflectance and lightmore » emission.« less
Single-bunch synchrotron shutter
Norris, James R.; Tang, Jau-Huei; Chen, Lin; Thurnauer, Marion
1993-01-01
An apparatus for selecting a single synchrotron pulse from the millions of pulses provided per second from a synchrotron source includes a rotating spindle located in the path of the synchrotron pulses. The spindle has multiple faces of a highly reflective surface, and having a frequency of rotation f. A shutter is spaced from the spindle by a radius r, and has an open position and a closed position. The pulses from the synchrotron are reflected off the spindle to the shutter such that the speed s of the pulses at the shutter is governed by: s=4.times..pi..times.r.times.f. such that a single pulse is selected for transmission through an open position of the shutter.
Extending the Deep Blue aerosol record from SeaWiFS and MODIS to NPP-VIIRS
NASA Technical Reports Server (NTRS)
Sayer, Andrew M.; Hsu, Nai-Yung Christina; Bettenhausen, Corey; Lee, Jaehwa
2015-01-01
Deep Blue expands AOD coverage to deserts and other bright surfaces. Using multiple similar satellite sensors enables us to obtain a long data record. The Deep Blue family consists of three separate aerosol optical depth (AOD) retrieval algorithms: 1. Bright Land: Surface reflectance database, BRDF correction. AOD retrieved separately at each of 412, 470/490, (650) nm. SSA retrieved for heavy dust events. 2. Dark Land: Spectral/directional surface reflectance relationship. AOD retrieved separately at 470/490 and 650 nm. 3. Water: Surface BRDF including glint, foam, underlight. Multispectral inversion (Not present in MODISdataset) All report the AOD at 550 nm, and Ångström exponent (AE).
Measuring Ocean Surface Waves using Signal Reflections from Geostationary Satellites
NASA Astrophysics Data System (ADS)
Ouellette, J. D.; Dowgiallo, D. J.; Hwang, P. A.; Toporkov, J. V.
2017-12-01
The delay-Doppler response of communications signals (such as GNSS) reflected off the ocean surface is well-known to have properties which strongly correlate with surface wind conditions and ocean surface roughness. This study extends reflectometry techniques currently applied to the GNSS constellation to include geostationary communications satellites such as XM Radio. In this study, ocean wind conditions and significant wave height will be characterized using the delay-Doppler response of XM Radio signals reflected off of ocean surface waves. Using geostationary satellites for reflectometry-based remote sensing of oceans presents two primary advantages. First, longer coherent integration times can be achieved, which boosts signal processing gain and allows for finer Doppler resolution. Second, being designed for wide-area broadcast communications, the ground-received power of these geostationary satellite signals tends to be many orders of magnitude stronger than e.g. GNSS signals. Reflections of such signals from the ocean are strong enough to be received well outside of the specular region. This flexibility of viewing geometry allows signal processing to be performed on data received from multiple incidence/reception angles, which can provide a more complete characterization of ocean surface roughness and surface wind vectors. This work will include studies of simulated and measured delay-Doppler behavior of XM Radio signals reflected from dynamic ocean surfaces. Simulation studies will include inter-comparison between a number of hydrodynamic and electromagnetic models. Results from simulations will be presented as delay-Doppler plots and will be compared with delay-Doppler behavior observed in measured data. Measured data will include field campaign results from early- to mid-2017 in which the US Naval Research Laboratory's in-house XM reflectometer-receiver was deployed near the coasts of Virginia and North Carolina to observe reflections from wind-driven ocean waves. Preliminary results from a significant wave height retrieval algorithm will also be presented.
Multiple diffraction in an icosahedral Al-Cu-Fe quasicrystal
NASA Astrophysics Data System (ADS)
Fan, C. Z.; Weber, Th.; Deloudi, S.; Steurer, W.
2011-07-01
In order to reveal its influence on quasicrystal structure analysis, multiple diffraction (MD) effects in an icosahedral Al-Cu-Fe quasicrystal have been investigated in-house on an Oxford Diffraction four-circle diffractometer equipped with an Onyx™ CCD area detector and MoKα radiation. For that purpose, an automated approach for Renninger scans (ψ-scans) has been developed. Two weak reflections were chosen as the main reflections (called P) in the present measurements. As is well known for periodic crystals, it is also observed for this quasicrystal that the intensity of the main reflection may significantly increase if the simultaneous (H) and the coupling (P-H) reflections are both strong, while there is no obvious MD effect if one of them is weak. The occurrence of MD events during ψ-scans has been studied based on an ideal structure model and the kinematical MD theory. The reliability of the approach is revealed by the good agreement between simulation and experiment. It shows that the multiple diffraction effect is quite significant.
Defense Acquisition Research Journal. Volume 21, Number 2, Issue 69
2014-04-01
that quickly meets their needs, not a slow and lumbering bureau- cracy better suited to the last century. As important, our military men and women...resolution of urgent needs/ONS. Joint organizations and other military services, however, are not included in this table. As reflected in Table 2, multiple...urgent capability shortfall, the process endures. Materiel release is required for all nonexpendable materiel; high-density military expendables
Studies of the Reflection, Refraction and Internal Reflection of Light
ERIC Educational Resources Information Center
Lanchester, P. C.
2014-01-01
An inexpensive apparatus and associated experiments are described for studying the basic laws of reflection and refraction of light at an air-glass interface, and multiple internal reflections within a glass block. In order to motivate students and encourage their active participation, a novel technique is described for determining the refractive…
Ueda-Arakawa, Naoko; Ooto, Sotaro; Tsujikawa, Akitaka; Yamashiro, Kenji; Oishi, Akio; Yoshimura, Nagahisa
2013-03-01
To identify reticular pseudodrusen (RPD) in age-related macular degeneration using multiple imaging modalities, including the blue channel image of fundus photography, infrared reflectance (IR), fundus autofluorescence, near-infrared fundus autofluorescence, confocal blue reflectance, indocyanine green angiography, and spectral-domain optical coherence tomography (SD-OCT), and to compare the sensitivities and specificities of these modalities for detecting RPD. This study included 220 eyes from 114 patients with newly diagnosed age-related macular degeneration. Patients underwent fundus photography, IR, fundus autofluorescence, near-infrared fundus autofluorescence, confocal blue reflectance, indocyanine green angiography, and SD-OCT in both eyes. Eyes were diagnosed with RPD if they showed reticular patterns on at least two of the seven imaging modalities. Thirty-seven eyes were diagnosed with RPD. However, SD-OCT and IR had the highest sensitivity (94.6%), and at the same time, SD-OCT had a high specificity (98.4%). The blue channel of color fundus photography, confocal blue reflectance, and indocyanine green angiography had a specificity of 100% but had lower sensitivity than that of SD-OCT and IR. For detecting RPD, IR and SD-OCT had the highest sensitivity. Although SD-OCT had the highest sensitivity and specificity, RPD detection should be confirmed using more than one modality for increased accuracy.
Range-gated field disturbance sensor with range-sensitivity compensation
McEwan, T.E.
1996-05-28
A field disturbance sensor operates with relatively low power, provides an adjustable operating range, is not hypersensitive at close range, allows co-location of multiple sensors, and is inexpensive to manufacture. The sensor includes a transmitter that transmits a sequence of transmitted bursts of electromagnetic energy. The transmitter frequency is modulated at an intermediate frequency. The sequence of bursts has a burst repetition rate, and each burst has a burst width and comprises a number of cycles at a transmitter frequency. The sensor includes a receiver which receives electromagnetic energy at the transmitter frequency, and includes a mixer which mixes a transmitted burst with reflections of the same transmitted burst to produce an intermediate frequency signal. Circuitry, responsive to the intermediate frequency signal indicates disturbances in the sensor field. Because the mixer mixes the transmitted burst with reflections of the transmitted burst, the burst width defines the sensor range. The burst repetition rate is randomly or pseudorandomly modulated so that bursts in the sequence of bursts have a phase which varies. 8 figs.
Range-gated field disturbance sensor with range-sensitivity compensation
McEwan, Thomas E.
1996-01-01
A field disturbance sensor operates with relatively low power, provides an adjustable operating range, is not hypersensitive at close range, allows co-location of multiple sensors, and is inexpensive to manufacture. The sensor includes a transmitter that transmits a sequence of transmitted bursts of electromagnetic energy. The transmitter frequency is modulated at an intermediate frequency. The sequence of bursts has a burst repetition rate, and each burst has a burst width and comprises a number of cycles at a transmitter frequency. The sensor includes a receiver which receives electromagnetic energy at the transmitter frequency, and includes a mixer which mixes a transmitted burst with reflections of the same transmitted burst to produce an intermediate frequency signal. Circuitry, responsive to the intermediate frequency signal indicates disturbances in the sensor field. Because the mixer mixes the transmitted burst with reflections of the transmitted burst, the burst width defines the sensor range. The burst repetition rate is randomly or pseudorandomly modulated so that bursts in the sequence of bursts have a phase which varies.
Evaluating Multispectral Snowpack Reflectivity With Changing Snow Correlation Lengths
NASA Technical Reports Server (NTRS)
Kang, Do Hyuk; Barros, Ana P.; Kim, Edward J.
2016-01-01
This study investigates the sensitivity of multispectral reflectivity to changing snow correlation lengths. Matzler's ice-lamellae radiative transfer model was implemented and tested to evaluate the reflectivity of snow correlation lengths at multiple frequencies from the ultraviolet (UV) to the microwave bands. The model reveals that, in the UV to infrared (IR) frequency range, the reflectivity and correlation length are inversely related, whereas reflectivity increases with snow correlation length in the microwave frequency range. The model further shows that the reflectivity behavior can be mainly attributed to scattering rather than absorption for shallow snowpacks. The largest scattering coefficients and reflectivity occur at very small correlation lengths (approximately 10(exp -5 m) for frequencies higher than the IR band. In the microwave range, the largest scattering coefficients are found at millimeter wavelengths. For validation purposes, the ice-lamella model is coupled with a multilayer snow physics model to characterize the reflectivity response of realistic snow hydrological processes. The evolution of the coupled model simulated reflectivities in both the visible and the microwave bands is consistent with satellite-based reflectivity observations in the same frequencies. The model results are also compared with colocated in situ snow correlation length measurements (Cold Land Processes Field Experiment 2002-2003). The analysis and evaluation of model results indicate that the coupled multifrequency radiative transfer and snow hydrology modeling system can be used as a forward operator in a data-assimilation framework to predict the status of snow physical properties, including snow correlation length.
Intrinsic Fabry-Perot optical fiber sensors and their multiplexing
Wang, Anbo
2007-12-11
An intrinsic Fabry-Perot optical sensor includes a thin film sandwiched between two fiber ends. When light is launched into the fiber, two reflections are generated at the two fiber/thin film interfaces due to a difference in refractive indices between the fibers and the film, giving rise to the sensor output. In another embodiment, a portion of the cladding of a fiber is removed, creating two parallel surfaces. Part of the evanescent fields of light propagating in the fiber is reflected at each of the surfaces, giving rise to the sensor output. In a third embodiment, the refractive index of a small portion of a fiber is changed through exposure to a laser beam or other radiation. Interference between reflections at the ends of the small portion give rise to the sensor output. Multiple sensors along a single fiber are multiplexed using an optical time domain reflectometry method.
Measurement and models of bent KAP(001) crystal integrated reflectivity and resolution (invited)
NASA Astrophysics Data System (ADS)
Loisel, G. P.; Wu, M.; Stolte, W.; Kruschwitz, C.; Lake, P.; Dunham, G. S.; Bailey, J. E.; Rochau, G. A.
2016-11-01
The Advanced Light Source beamline-9.3.1 x-rays are used to calibrate the rocking curve of bent potassium acid phthalate (KAP) crystals in the 2.3-4.5 keV photon-energy range. Crystals are bent on a cylindrically convex substrate with a radius of curvature ranging from 2 to 9 in. and also including the flat case to observe the effect of bending on the KAP spectrometric properties. As the bending radius increases, the crystal reflectivity converges to the mosaic crystal response. The X-ray Oriented Programs (xop) multi-lamellar model of bent crystals is used to model the rocking curve of these crystals and the calibration data confirm that a single model is adequate to reproduce simultaneously all measured integrated reflectivities and rocking-curve FWHM for multiple radii of curvature in both 1st and 2nd order of diffraction.
Measurement and models of bent KAP(001) crystal integrated reflectivity and resolution (invited)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Loisel, G. P., E-mail: gploise@sandia.gov; Wu, M.; Lake, P.
2016-11-15
The Advanced Light Source beamline-9.3.1 x-rays are used to calibrate the rocking curve of bent potassium acid phthalate (KAP) crystals in the 2.3-4.5 keV photon-energy range. Crystals are bent on a cylindrically convex substrate with a radius of curvature ranging from 2 to 9 in. and also including the flat case to observe the effect of bending on the KAP spectrometric properties. As the bending radius increases, the crystal reflectivity converges to the mosaic crystal response. The X-ray Oriented Programs (XOP) multi-lamellar model of bent crystals is used to model the rocking curve of these crystals and the calibration datamore » confirm that a single model is adequate to reproduce simultaneously all measured integrated reflectivities and rocking-curve FWHM for multiple radii of curvature in both 1st and 2nd order of diffraction.« less
The Landsat Image Mosaic of Antarctica
Bindschadler, Robert; Vornberger, P.; Fleming, A.; Fox, A.; Mullins, J.; Binnie, D.; Paulsen, S.J.; Granneman, Brian J.; Gorodetzky, D.
2008-01-01
The Landsat Image Mosaic of Antarctica (LIMA) is the first true-color, high-spatial-resolution image of the seventh continent. It is constructed from nearly 1100 individually selected Landsat-7 ETM+ scenes. Each image was orthorectified and adjusted for geometric, sensor and illumination variations to a standardized, almost seamless surface reflectance product. Mosaicing to avoid clouds produced a high quality, nearly cloud-free benchmark data set of Antarctica for the International Polar Year from images collected primarily during 1999-2003. Multiple color composites and enhancements were generated to illustrate additional characteristics of the multispectral data including: the true appearance of the surface; discrimination between snow and bare ice; reflectance variations within bright snow; recovered reflectance values in regions of sensor saturation; and subtle topographic variations associated with ice flow. LIMA is viewable and individual scenes or user defined portions of the mosaic are downloadable at http://lima.usgs.gov. Educational materials associated with LIMA are available at http://lima.nasa.gov.
Lee, Jimin; Hustad, Katherine C.; Weismer, Gary
2014-01-01
Purpose Speech acoustic characteristics of children with cerebral palsy (CP) were examined with a multiple speech subsystem approach; speech intelligibility was evaluated using a prediction model in which acoustic measures were selected to represent three speech subsystems. Method Nine acoustic variables reflecting different subsystems, and speech intelligibility, were measured in 22 children with CP. These children included 13 with a clinical diagnosis of dysarthria (SMI), and nine judged to be free of dysarthria (NSMI). Data from children with CP were compared to data from age-matched typically developing children (TD). Results Multiple acoustic variables reflecting the articulatory subsystem were different in the SMI group, compared to the NSMI and TD groups. A significant speech intelligibility prediction model was obtained with all variables entered into the model (Adjusted R-squared = .801). The articulatory subsystem showed the most substantial independent contribution (58%) to speech intelligibility. Incremental R-squared analyses revealed that any single variable explained less than 9% of speech intelligibility variability. Conclusions Children in the SMI group have articulatory subsystem problems as indexed by acoustic measures. As in the adult literature, the articulatory subsystem makes the primary contribution to speech intelligibility variance in dysarthria, with minimal or no contribution from other systems. PMID:24824584
Lee, Jimin; Hustad, Katherine C; Weismer, Gary
2014-10-01
Speech acoustic characteristics of children with cerebral palsy (CP) were examined with a multiple speech subsystems approach; speech intelligibility was evaluated using a prediction model in which acoustic measures were selected to represent three speech subsystems. Nine acoustic variables reflecting different subsystems, and speech intelligibility, were measured in 22 children with CP. These children included 13 with a clinical diagnosis of dysarthria (speech motor impairment [SMI] group) and 9 judged to be free of dysarthria (no SMI [NSMI] group). Data from children with CP were compared to data from age-matched typically developing children. Multiple acoustic variables reflecting the articulatory subsystem were different in the SMI group, compared to the NSMI and typically developing groups. A significant speech intelligibility prediction model was obtained with all variables entered into the model (adjusted R2 = .801). The articulatory subsystem showed the most substantial independent contribution (58%) to speech intelligibility. Incremental R2 analyses revealed that any single variable explained less than 9% of speech intelligibility variability. Children in the SMI group had articulatory subsystem problems as indexed by acoustic measures. As in the adult literature, the articulatory subsystem makes the primary contribution to speech intelligibility variance in dysarthria, with minimal or no contribution from other systems.
How PV system ownership can impact the market value of residential homes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Klise, Geoffrey Taylor; Johnson, Jamie L.
2014-01-01
There are multiple ways for a homeowner to obtain the electricity generating and savings benefits offered by a photovoltaic (PV) system. These include purchasing a PV system through various financing mechanisms, or by leasing the PV system from a third party with multiple options that may include purchase, lease renewal or PV system removal. The different ownership options available to homeowners presents a challenge to appraisal and real estate professionals during a home sale or refinance in terms of how to develop a value that is reflective of the PV systems operational characteristics, local market conditions, and lender and underwritermore » requirements. This paper presents these many PV system ownership options with a discussion of what considerations an appraiser must make when developing the contributory value of a PV system to a residential property.« less
ERIC Educational Resources Information Center
Meyer, Merna; Wood, Lesley
2017-01-01
In this article, I critically reflect on my own learning during a community-based, service-learning pilot project, highlighting the multiple roles that were required of me as facilitator. I provided opportunity for student teachers in a Creative Arts module to engage with youth from a local township community. The purpose of the participatory…
ERIC Educational Resources Information Center
Taylor, Kim; Preece, David
2010-01-01
This article reflects on how the first author has adapted aspects of the TEACCH structured teaching approach--developed for use with students with autism--in her work with students with multiple disabilities and visual impairment (MDVI) in a special secondary school for students with severe learning difficulties in England. A brief overview of the…
Bourlier, Christophe
2006-08-20
The emissivity from a stationary random rough surface is derived by taking into account the multiple reflections and the shadowing effect. The model is applied to the ocean surface. The geometric optics approximation is assumed to be valid, which means that the rough surface is modeled as a collection of facets reflecting locally the light in the specular direction. In particular, the emissivity with zero, single, and double reflections are analytically calculated, and each contribution is studied numerically by considering a 1D sea surface observed in the near infrared band. The model is also compared with results computed from a Monte Carlo ray-tracing method.
Pruyne, David
2016-01-01
Formins are a widespread family of eukaryotic cytoskeleton-organizing proteins. Many species encode multiple formin isoforms, and for animals, much of this reflects the presence of multiple conserved subtypes. Earlier phylogenetic analyses identified seven major formin subtypes in animals (DAAM, DIAPH, FHOD, FMN, FMNL, INF, and GRID2IP/delphilin), but left a handful of formins, particularly from nematodes, unassigned. In this new analysis drawing from genomic data from a wider range of taxa, nine formin subtypes are identified that encompass all the animal formins analyzed here. Included in this analysis are Multiple Wing Hairs proteins (MWH), which bear homology to formin N-terminal domains. Originally identified in Drosophila melanogaster and other arthropods, MWH-related proteins are also identified here in some nematodes (including Caenorhabditis elegans), and are shown to be related to a novel MWH-related formin (MWHF) subtype. One surprising result of this work is the discovery that a family of pleckstrin homology domain-containing formins (PHCFs) is represented in many vertebrates, but is strikingly absent from placental mammals. Consistent with a relatively recent loss of this formin, the human genome retains fragments of a defunct homologous formin gene.
Briggs, Adam D M; Scarborough, Peter; Wolstenholme, Jane
2018-01-01
Healthcare interventions, and particularly those in public health may affect multiple diseases and significantly prolong life. No consensus currently exists for how to estimate comparable healthcare costs across multiple diseases for use in health and public health cost-effectiveness models. We aim to describe a method for estimating comparable disease specific English healthcare costs as well as future healthcare costs from diseases unrelated to those modelled. We use routine national datasets including programme budgeting data and cost curves from NHS England to estimate annual per person costs for diseases included in the PRIMEtime model as well as age and sex specific costs due to unrelated diseases. The 2013/14 annual cost to NHS England per prevalent case varied between £3,074 for pancreatic cancer and £314 for liver disease. Costs due to unrelated diseases increase with age except for a secondary peak at 30-34 years for women reflecting maternity resource use. The methodology described allows health and public health economic modellers to estimate comparable English healthcare costs for multiple diseases. This facilitates the direct comparison of different health and public health interventions enabling better decision making.
ERIC Educational Resources Information Center
Isik-Ercan, Zeynep; Perkins, Kelley
2017-01-01
Drawing from sociocultural theories of learning and literature on reflection in educational contexts, this article describes reflective practices as a meaning-making and action engine to support early childhood education practitioners' professional knowledge, skills, and dispositions. We argue that the process of reflection requires a differential…
ERIC Educational Resources Information Center
Myers, Casey Y.; Smith, Kylie A.; Tesar, Marek
2017-01-01
Despite the ubiquity of reflective practice in education, mandating reflective processes within sanctioned frameworks is inherently problematic, as it may lead to reproduction, standardization, and forced universalities, rather than the critical and innovative pedagogy they intend. This article engages with reflection through both the metaphor and…
The Health Policy Process in Vietnam: Going Beyond Kingdon’s Multiple Streams Theory
Kane, Sumit
2016-01-01
This commentary reflects upon the article along three broad lines. It reflects on the theoretical choices and omissions, particularly highlighting why it is important to adapt the multiple streams framework (MSF) when applying it in a socio-political context like Vietnam’s. The commentary also reflects upon the analytical threads tackled by Ha et al; for instance, it highlights the opportunities offered by, and raises questions about the centrality of the Policy Entrepreneur in getting the policy onto the political agenda and in pushing it through. The commentary also dwells on the implications of the article for development aid policies and practices. Throughout, the commentary signposts possible themes for Ha et al to consider for further analysis, and more generally, for future research using Kingdon’s multiple streams theory. PMID:27694671
NASA Astrophysics Data System (ADS)
Zhang, Jie; Ding, Lan; Liang, Changneng; Xiao, Yiming; Xu, Wen
2017-11-01
We develop a multiple reflection model (MRM) for the examination of infrared transmission properties of a graphene/substrate system. The incident angle and the multiple reflection beams in the substrate with finite thickness are taken into consideration. The model can be applied to predict the optical responses of graphene/substrate systems or to extract the real part of the optical conductance of graphene from the experimental measurement. As an example, we calculate the relative transmittance of graphene/quartz and graphene/sapphire systems by using MRM and provide an experimental verification in the near-infrared range. The measured results show good agreement with the calculated ones. Our method can be easily extended to accurately and non-invasively identify the layer numbers of other 2D materials, and assess the quality of them.
Seismic reflection imaging with conventional and unconventional sources
NASA Astrophysics Data System (ADS)
Quiros Ugalde, Diego Alonso
This manuscript reports the results of research using both conventional and unconventional energy sources as well as conventional and unconventional analysis to image crustal structure using reflected seismic waves. The work presented here includes the use of explosions to investigate the Taiwanese lithosphere, the use of 'noise' from railroads to investigate the shallow subsurface of the Rio Grande rift, and the use of microearthquakes to image subsurface structure near an active fault zone within the Appalachian mountains. Chapter 1 uses recordings from the land refraction and wide-angle reflection component of the Taiwan Integrated Geodynamic Research (TAIGER) project. The most prominent reflection feature imaged by these surveys is an anomalously strong reflector found in northeastern Taiwan. The goal of this chapter is to analyze the TAIGER recordings and to place the reflector into a geologic framework that fits with the modern tectonic kinematics of the region. Chapter 2 uses railroad traffic as a source for reflection profiling within the Rio Grande rift. Here the railroad recordings are treated in an analogous way to Vibroseis recordings. These results suggest that railroad noise in general can be a valuable new tool in imaging and characterizing the shallow subsurface in environmental and geotechnical studies. In chapters 3 and 4, earthquakes serve as the seismic imaging source. In these studies the methodology of Vertical Seismic Profiling (VSP) is borrowed from the oil and gas industry to develop reflection images. In chapter 3, a single earthquake is used to probe a small area beneath Waterboro, Maine. In chapter 4, the same method is applied to multiple earthquakes to take advantage of the increased redundancy that results from multiple events illuminating the same structure. The latter study demonstrates how dense arrays can be a powerful new tool for delineating, and monitoring temporal changes of deep structure in areas characterized by significant seismic activity.
NASA Astrophysics Data System (ADS)
Bian, A.; Gantela, C.
2014-12-01
Strong multiples were observed in marine seismic data of Los Angeles Regional Seismic Experiment (LARSE).It is crucial to eliminate these multiples in conventional ray-based or one-way wave-equation based depth image methods. As long as multiples contain information of target zone along travelling path, it's possible to use them as signal, to improve the illumination coverage thus enhance the image quality of structural boundaries. Reverse time migration including multiples is a two-way wave-equation based prestack depth image method that uses both primaries and multiples to map structural boundaries. Several factors, including source wavelet, velocity model, back ground noise, data acquisition geometry and preprocessing workflow may influence the quality of image. The source wavelet is estimated from direct arrival of marine seismic data. Migration velocity model is derived from integrated model building workflow, and the sharp velocity interfaces near sea bottom needs to be preserved in order to generate multiples in the forward and backward propagation steps. The strong amplitude, low frequency marine back ground noise needs to be removed before the final imaging process. High resolution reverse time image sections of LARSE Lines 1 and Line 2 show five interfaces: depth of sea-bottom, base of sedimentary basins, top of Catalina Schist, a deep layer and a possible pluton boundary. Catalina Schist shows highs in the San Clemente ridge, Emery Knoll, Catalina Ridge, under Catalina Basin on both the lines, and a minor high under Avalon Knoll. The high of anticlinal fold in Line 1 is under the north edge of Emery Knoll and under the San Clemente fault zone. An area devoid of any reflection features are interpreted as sides of an igneous plume.
TOGA - A GNSS Reflections Instrument for Remote Sensing Using Beamforming
NASA Technical Reports Server (NTRS)
Esterhuizen, S.; Meehan, T. K.; Robison, D.
2009-01-01
Remotely sensing the Earth's surface using GNSS signals as bi-static radar sources is one of the most challenging applications for radiometric instrument design. As part of NASA's Instrument Incubator Program, our group at JPL has built a prototype instrument, TOGA (Time-shifted, Orthometric, GNSS Array), to address a variety of GNSS science needs. Observing GNSS reflections is major focus of the design/development effort. The TOGA design features a steerable beam antenna array which can form a high-gain antenna pattern in multiple directions simultaneously. Multiple FPGAs provide flexible digital signal processing logic to process both GPS and Galileo reflections. A Linux OS based science processor serves as experiment scheduler and data post-processor. This paper outlines the TOGA design approach as well as preliminary results of reflection data collected from test flights over the Pacific ocean. This reflections data demonstrates observation of the GPS L1/L2C/L5 signals.
Multiple-reflection model of human skin and estimation of pigment concentrations
NASA Astrophysics Data System (ADS)
Ohtsuki, Rie; Tominaga, Shoji; Tanno, Osamu
2012-07-01
We describe a new method for estimating the concentrations of pigments in the human skin using surface spectral reflectance. We derive an equation that expresses the surface spectral reflectance of the human skin. First, we propose an optical model of the human skin that accounts for the stratum corneum. We also consider the difference between the scattering coefficient of the epidermis and that of the dermis. We then derive an equation by applying the Kubelka-Munk theory to an optical model of the human skin. Unlike a model developed in a recent study, the present equation considers pigments as well as multiple reflections and the thicknesses of the skin layers as factors that affect the color of the human skin. In two experiments, we estimate the pigment concentrations using the measured surface spectral reflectances. Finally, we confirm the feasibility of the concentrations estimated by the proposed method by evaluating the estimated pigment concentrations in the skin.
Plass, G N; Kattawar, G W
1972-12-01
The degree of polarization as well as the direction of the polarization are calculated by a Monte Carlo method for the reflected and transmitted photons from the earth's atmosphere. The solar photons are followed through multiple collisions with the aerosols and the Rayleigh scattering centers in the atmosphere. The aerosol number density as well as the ratio of aerosol to Rayleigh scattering vary with height. The aerosol index of refraction is assumed to be 1.55. The proportion of aerosol to Rayleigh scattering is appropriately chosen at each wavelength (lambda = 0.4 micro and 0.7 micro); ozone absorption is included where appropriate. Three different aerosol number densities are used to study the effects of aerosol variations. Results are given for a solar zenith angle of 81.37 degrees and various surface albedos. The radiance and polarization of the reflected and transmitted photons is particularly sensitive to the amount of aerosols in the atmosphere at certain angles of observation. The direction of pola ization shows little dependence on the surface albedo.
Plasmonic Metallurgy Enabled by DNA.
Ross, Michael B; Ku, Jessie C; Lee, Byeongdu; Mirkin, Chad A; Schatz, George C
2016-04-13
Mixed silver and gold plasmonic nanoparticle architectures are synthesized using DNA-programmable assembly, unveiling exquisitely tunable optical properties that are predicted and explained both by effective thin-film models and explicit electrodynamic simulations. These data demonstrate that the manner and ratio with which multiple metallic components are arranged can greatly alter optical properties, including tunable color and asymmetric reflectivity behavior of relevance for thin-film applications. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Wide-band/angle Blazed Surfaces using Multiple Coupled Blazing Resonances
Memarian, Mohammad; Li, Xiaoqiang; Morimoto, Yasuo; Itoh, Tatsuo
2017-01-01
Blazed gratings can reflect an oblique incident wave back in the path of incidence, unlike mirrors and metal plates that only reflect specular waves. Perfect blazing (and zero specular scattering) is a type of Wood’s anomaly that has been observed when a resonance condition occurs in the unit-cell of the blazed grating. Such elusive anomalies have been studied thus far as individual perfect blazing points. In this work, we present reflective blazed surfaces that, by design, have multiple coupled blazing resonances per cell. This enables an unprecedented way of tailoring the blazing operation, for widening and/or controlling of blazing bandwidth and incident angle range of operation. The surface can thus achieve blazing at multiple wavelengths, each corresponding to different incident wavenumbers. The multiple blazing resonances are combined similar to the case of coupled resonator filters, forming a blazing passband between the incident wave and the first grating order. Blazed gratings with single and multi-pole blazing passbands are fabricated and measured showing increase in the bandwidth of blazing/specular-reflection-rejection, demonstrated here at X-band for convenience. If translated to appropriate frequencies, such technique can impact various applications such as Littrow cavities and lasers, spectroscopy, radar, and frequency scanned antenna reflectors. PMID:28211506
Confocal and dermoscopic features of basal cell carcinoma in Gorlin-Goltz syndrome: A case report.
Casari, Alice; Argenziano, Giuseppe; Moscarella, Elvira; Lallas, Aimilios; Longo, Caterina
2017-05-01
Gorlin-Goltz (GS) syndrome is an autosomal dominant disease linked to a mutation in the PTCH gene. Major criteria include the onset of multiple basal cell carcinoma (BCC), keratocystic odontogenic tumours in the jaws and bifid ribs. Dermoscopy and reflectance confocal microscopy represent imaging tools that are able to increase the diagnostic accuracy of skin cancer in a totally noninvasive manner, without performing punch biopsies. Here we present a case of a young woman in whom the combined approach of dermoscopy and RCM led to the identification of multiple small inconspicuous lesions as BCC and thus to the diagnosis of GS syndrome. © 2016 The Australasian College of Dermatologists.
NASA Technical Reports Server (NTRS)
Whitlock, C. H.; Kuo, C. Y.
1979-01-01
The objective of this paper is to define optical physics and/or environmental conditions under which the linear multiple-regression should be applicable. An investigation of the signal-response equations is conducted and the concept is tested by application to actual remote sensing data from a laboratory experiment performed under controlled conditions. Investigation of the signal-response equations shows that the exact solution for a number of optical physics conditions is of the same form as a linearized multiple-regression equation, even if nonlinear contributions from surface reflections, atmospheric constituents, or other water pollutants are included. Limitations on achieving this type of solution are defined.
Radiative transfer in multilayered random medium with laminar structure - Green's function approach
NASA Technical Reports Server (NTRS)
Karam, M. A.; Fung, A. K.
1986-01-01
For a multilayered random medium with a laminar structure a Green's function approach is introduced to obtain the emitted intensity due to an arbitrary point source. It is then shown that the approach is applicable to both active and passive remote sensing. In active remote sensing, the computed radar backscattering cross section for the multilayered medium includes the effects of both volume multiple scattering and surface multiple scattering at the layer boundaries. In passive remote sensing, the brightness temperature is obtained for arbitrary temperature profiles in the layers. As an illustration the brightness temperature and reflectivity are calculated for a bounded layer and compared with results in the literature.
History of Cognitive-Behavioral Therapy (CBT) in Youth
Benjamin, Courtney L.; Puleo, Connor M.; Settipani, Cara A.; Brodman, Douglas M.; Edmunds, Julie M.; Cummings, Colleen M.
2011-01-01
Synopsis CBT represents a combination of behavioral and cognitive theories of human behavior and psychopathology, and a melding of emotional, familial, and peer influences. The numerous intervention strategies that comprise CBT reflect its complex and integrative nature and include such topics as extinction, habituation, modeling, cognitive restructuring, problem-solving, and the development of coping strategies, mastery, and a sense of self-control. CBT targets multiple areas of potential vulnerability (e.g., cognitive, behavioral, affective) with developmentally-guided strategies and traverses multiple intervention pathways. Although CBT is often considered the “first line treatment” for many psychological disorders in youth, additional work is necessary to address treatment non-responders and to facilitate the dissemination of efficacious CBT approaches. PMID:21440849
A neuroimaging investigation of attribute framing and individual differences
Murch, Kevin B.
2014-01-01
Functional magnetic resonance imaging was used to evaluate the neural basis of framing effects. We tested the reflexive and reflective systems model of social cognition as it relates to framing. We also examined the relationships among frame susceptibility, intelligence and personality measures. Participants evaluated whether personal attributes applied to themselves from multiple perspectives and in positive and negative frames. Participants rated whether each statement was descriptive or not and endorsed positive frames more than negative frames. Individual differences on frame decisions enabled us to form high and low frame susceptibility groups. Endorsement of frame-consistent attributes was associated with personality factors, cognitive reflection and intelligence. Reflexive brain regions were associated with positive frames while reflective areas were associated with negative frames. Region of Interest analyses showed that frame-inconsistent responses were associated with increased activation within reflective cognitive control regions including the left dorsolateral prefrontal cortex (PFC), dorsomedial PFC and left ventrolateral PFC. Frame-consistent responses were associated with increased activation in the right orbitofrontal cortex. These results demonstrate that individual differences in frame susceptibility influence personal attribute evaluations. Overall, this study clarifies the neural correlates of the reflective and reflexive systems of social cognition as applied to decisions about social attributions. PMID:23988759
Acoustic radiosity for computation of sound fields in diffuse environments
NASA Astrophysics Data System (ADS)
Muehleisen, Ralph T.; Beamer, C. Walter
2002-05-01
The use of image and ray tracing methods (and variations thereof) for the computation of sound fields in rooms is relatively well developed. In their regime of validity, both methods work well for prediction in rooms with small amounts of diffraction and mostly specular reflection at the walls. While extensions to the method to include diffuse reflections and diffraction have been made, they are limited at best. In the fields of illumination and computer graphics the ray tracing and image methods are joined by another method called luminous radiative transfer or radiosity. In radiosity, an energy balance between surfaces is computed assuming diffuse reflection at the reflective surfaces. Because the interaction between surfaces is constant, much of the computation required for sound field prediction with multiple or moving source and receiver positions can be reduced. In acoustics the radiosity method has had little attention because of the problems of diffraction and specular reflection. The utility of radiosity in acoustics and an approach to a useful development of the method for acoustics will be presented. The method looks especially useful for sound level prediction in industrial and office environments. [Work supported by NSF.
LIDAR pulse coding for high resolution range imaging at improved refresh rate.
Kim, Gunzung; Park, Yongwan
2016-10-17
In this study, a light detection and ranging system (LIDAR) was designed that codes pixel location information in its laser pulses using the direct- sequence optical code division multiple access (DS-OCDMA) method in conjunction with a scanning-based microelectromechanical system (MEMS) mirror. This LIDAR can constantly measure the distance without idle listening time for the return of reflected waves because its laser pulses include pixel location information encoded by applying the DS-OCDMA. Therefore, this emits in each bearing direction without waiting for the reflected wave to return. The MEMS mirror is used to deflect and steer the coded laser pulses in the desired bearing direction. The receiver digitizes the received reflected pulses using a low-temperature-grown (LTG) indium gallium arsenide (InGaAs) based photoconductive antenna (PCA) and the time-to-digital converter (TDC) and demodulates them using the DS-OCDMA. When all of the reflected waves corresponding to the pixels forming a range image are received, the proposed LIDAR generates a point cloud based on the time-of-flight (ToF) of each reflected wave. The results of simulations performed on the proposed LIDAR are compared with simulations of existing LIDARs.
Analysis of Specular Reflections Off Geostationary Satellites
NASA Astrophysics Data System (ADS)
Jolley, A.
2016-09-01
Many photometric studies of artificial satellites have attempted to define procedures that minimise the size of datasets required to infer information about satellites. However, it is unclear whether deliberately limiting the size of datasets significantly reduces the potential for information to be derived from them. In 2013 an experiment was conducted using a 14 inch Celestron CG-14 telescope to gain multiple night-long, high temporal resolution datasets of six geostationary satellites [1]. This experiment produced evidence of complex variations in the spectral energy distribution (SED) of reflections off satellite surface materials, particularly during specular reflections. Importantly, specific features relating to the SED variations could only be detected with high temporal resolution data. An update is provided regarding the nature of SED and colour variations during specular reflections, including how some of the variables involved contribute to these variations. Results show that care must be taken when comparing observed spectra to a spectral library for the purpose of material identification; a spectral library that uses wavelength as the only variable will be unable to capture changes that occur to a material's reflected spectra with changing illumination and observation geometry. Conversely, colour variations with changing illumination and observation geometry might provide an alternative means of determining material types.
van Breen, Jolien A.; Spears, Russell; Kuppens, Toon; de Lemus, Soledad
2017-01-01
Across four studies, we examine multiple identities in the context of gender and propose that women's attitudes toward gender group membership are governed by two largely orthogonal dimensions of gender identity: identification with women and identification with feminists. We argue that identification with women reflects attitudes toward the content society gives to group membership: what does it mean to be a woman in terms of group characteristics, interests and values? Identification with feminists, on the other hand, is a politicized identity dimension reflecting attitudes toward the social position of the group: what does it mean to be a woman in terms of disadvantage, inequality, and relative status? We examine the utility of this multiple identity approach in four studies. Study 1 showed that identification with women reflects attitudes toward group characteristics, such as femininity and self-stereotyping, while identification with feminists reflects attitudes toward the group's social position, such as perceived sexism. The two dimensions are shown to be largely independent, and as such provide support for the multiple identity approach. In Studies 2–4, we examine the utility of this multiple identity approach in predicting qualitative differences in gender attitudes. Results show that specific combinations of identification with women and feminists predicted attitudes toward collective action and gender stereotypes. Higher identification with feminists led to endorsement of radical collective action (Study 2) and critical attitudes toward gender stereotypes (Studies 3–4), especially at lower levels of identification with women. The different combinations of high vs. low identification with women and feminists can be thought of as reflecting four theoretical identity “types.” A woman can be (1) strongly identified with neither women nor feminists (“low identifier”), (2) strongly identified with women but less so with feminists (“traditional identifier”), (3) strongly identified with both women and feminists (“dual identifier”), or (4) strongly identified with feminists but less so with women (“distinctive feminist”). In sum, by considering identification with women and identification with feminists as multiple identities we aim to show how the multiple identity approach predicts distinct attitudes to gender issues and offer a new perspective on gender identity. PMID:28713297
van Breen, Jolien A; Spears, Russell; Kuppens, Toon; de Lemus, Soledad
2017-01-01
Across four studies, we examine multiple identities in the context of gender and propose that women's attitudes toward gender group membership are governed by two largely orthogonal dimensions of gender identity: identification with women and identification with feminists. We argue that identification with women reflects attitudes toward the content society gives to group membership: what does it mean to be a woman in terms of group characteristics, interests and values? Identification with feminists, on the other hand, is a politicized identity dimension reflecting attitudes toward the social position of the group: what does it mean to be a woman in terms of disadvantage, inequality, and relative status? We examine the utility of this multiple identity approach in four studies. Study 1 showed that identification with women reflects attitudes toward group characteristics, such as femininity and self-stereotyping, while identification with feminists reflects attitudes toward the group's social position, such as perceived sexism. The two dimensions are shown to be largely independent, and as such provide support for the multiple identity approach. In Studies 2-4, we examine the utility of this multiple identity approach in predicting qualitative differences in gender attitudes. Results show that specific combinations of identification with women and feminists predicted attitudes toward collective action and gender stereotypes. Higher identification with feminists led to endorsement of radical collective action (Study 2) and critical attitudes toward gender stereotypes (Studies 3-4), especially at lower levels of identification with women. The different combinations of high vs. low identification with women and feminists can be thought of as reflecting four theoretical identity "types." A woman can be (1) strongly identified with neither women nor feminists ("low identifier"), (2) strongly identified with women but less so with feminists ("traditional identifier"), (3) strongly identified with both women and feminists ("dual identifier"), or (4) strongly identified with feminists but less so with women ("distinctive feminist"). In sum, by considering identification with women and identification with feminists as multiple identities we aim to show how the multiple identity approach predicts distinct attitudes to gender issues and offer a new perspective on gender identity.
Closed-loop multiple-scattering imaging with sparse seismic measurements
NASA Astrophysics Data System (ADS)
Berkhout, A. J. Guus
2018-03-01
In the theoretical situation of noise-free, complete data volumes (`perfect data'), seismic data matrices are fully filled and multiple-scattering operators have the minimum-phase property. Perfect data allow direct inversion methods to be successful in removing surface and internal multiple scattering. Moreover, under these perfect data conditions direct source wavefields realize complete illumination (no irrecoverable shadow zones) and, therefore, primary reflections (first-order response) can provide us with the complete seismic image. However, in practice seismic measurements always contain noise and we never have complete data volumes at our disposal. We actually deal with sparse data matrices that cannot be directly inverted. The message of this paper is that in practice multiple scattering (including source ghosting) must not be removed but must be utilized. It is explained that in the real world we badly need multiple scattering to fill the illumination gaps in the subsurface. It is also explained that the proposed multiple-scattering imaging algorithm gives us the opportunity to decompose both the image and the wavefields into order-based constituents, making the multiple scattering extension easy to apply. Last but not least, the algorithm allows us to use the minimum-phase property to validate and improve images in an objective way.
Duke, Pamela; Grosseman, Suely; Novack, Dennis H; Rosenzweig, Steven
2015-01-01
Medical student professionalism education is challenging in scope, purpose, and delivery, particularly in the clinical years when students in large universities are dispersed across multiple clinical sites. We initiated a faculty-facilitated, peer small group course for our third year students, creating virtual classrooms using social networking and online learning management system technologies. The course emphasized narrative self-reflection, group inquiry, and peer support. We conducted this study to analyze the effects of a professionalism course on third year medical students' empathy and self-reflection (two elements of professionalism) and their perceptions about the course. Students completed the Groningen Reflection Ability Scale (GRAS) and the Jefferson Scale of Empathy (JSE) before and after the course and provided anonymous online feedback. The results of the JSE before and after the course demonstrated preservation of empathy rather than its decline. In addition, there was a statistically significant increase in GRAS scores (p < 0.001), suggesting that the sharing of personal narratives may foster reflective ability and reflective practice among third year students. This study supports previous findings showing that students benefit from peer groups and discussion in a safe environment, which may include the use of a virtual group video platform.
Free Surface Downgoing VSP Multiple Imaging
NASA Astrophysics Data System (ADS)
Maula, Fahdi; Dac, Nguyen
2018-03-01
The common usage of a vertical seismic profile is to capture the reflection wavefield (upgoing wavefield) so that it can be used for further well tie or other interpretations. Borehole Seismic (VSP) receivers capture the reflection from below the well trajectory, traditionally no seismic image information above trajectory. The non-traditional way of processing the VSP multiple can be used to expand the imaging above the well trajectory. This paper presents the case study of using VSP downgoing multiples for further non-traditional imaging applications. In general, VSP processing, upgoing and downgoing arrivals are separated during processing. The up-going wavefield is used for subsurface illumination, whereas the downgoing wavefield and multiples are normally excluded from the processing. In a situation where the downgoing wavefield passes the reflectors several times (multiple), the downgoing wavefield carries reflection information. Its benefit is that it can be used for seismic tie up to seabed, and possibility for shallow hazards identifications. One of the concepts of downgoing imaging is widely known as mirror-imaging technique. This paper presents a case study from deep water offshore Vietnam. The case study is presented to demonstrate the robustness of the technique, and the limitations encountered during its processing.
Mining Multi-Aspect Reflection of News Events in Twitter: Discovery, Linking and Presentation
Wang, Jingjing; Tong, Wenzhu; Yu, Hongkun; Li, Min; Ma, Xiuli; Cai, Haoyan; Hanratty, Tim; Han, Jiawei
2015-01-01
A major event often has repercussions on both news media and microblogging sites such as Twitter. Reports from mainstream news agencies and discussions from Twitter complement each other to form a complete picture. An event can have multiple aspects (sub-events) describing it from multiple angles, each of which attracts opinions/comments posted on Twitter. Mining such reflections is interesting to both policy makers and ordinary people seeking information. In this paper, we propose a unified framework to mine multi-aspect reflections of news events in Twitter. We propose a novel and efficient dynamic hierarchical entity-aware event discovery model to learn news events and their multiple aspects. The aspects of an event are linked to their reflections in Twitter by a bootstrapped dataless classification scheme, which elegantly handles the challenges of selecting informative tweets under overwhelming noise and bridging the vocabularies of news and tweets. In addition, we demonstrate that our framework naturally generates an informative presentation of each event with entity graphs, time spans, news summaries and tweet highlights to facilitate user digestion. PMID:27034625
Mining Multi-Aspect Reflection of News Events in Twitter: Discovery, Linking and Presentation.
Wang, Jingjing; Tong, Wenzhu; Yu, Hongkun; Li, Min; Ma, Xiuli; Cai, Haoyan; Hanratty, Tim; Han, Jiawei
2015-11-01
A major event often has repercussions on both news media and microblogging sites such as Twitter. Reports from mainstream news agencies and discussions from Twitter complement each other to form a complete picture. An event can have multiple aspects (sub-events) describing it from multiple angles, each of which attracts opinions/comments posted on Twitter. Mining such reflections is interesting to both policy makers and ordinary people seeking information. In this paper, we propose a unified framework to mine multi-aspect reflections of news events in Twitter. We propose a novel and efficient dynamic hierarchical entity-aware event discovery model to learn news events and their multiple aspects. The aspects of an event are linked to their reflections in Twitter by a bootstrapped dataless classification scheme, which elegantly handles the challenges of selecting informative tweets under overwhelming noise and bridging the vocabularies of news and tweets. In addition, we demonstrate that our framework naturally generates an informative presentation of each event with entity graphs, time spans, news summaries and tweet highlights to facilitate user digestion.
Thermal removal from near-infrared imaging spectroscopy data of the Moon
Clark, R.N.; Pieters, C.M.; Green, R.O.; Boardman, J.W.; Petro, N.E.
2011-01-01
In the near-infrared from about 2 ??m to beyond 3 ??m, the light from the Moon is a combination of reflected sunlight and emitted thermal emission. There are multiple complexities in separating the two signals, including knowledge of the local solar incidence angle due to topography, phase angle dependencies, emissivity, and instrument calibration. Thermal emission adds to apparent reflectance, and because the emission's contribution increases over the reflected sunlight with increasing wavelength, absorption bands in the lunar reflectance spectra can be modified. In particular, the shape of the 2 ??m pyroxene band can be distorted by thermal emission, changing spectrally determined pyroxene composition and abundance. Because of the thermal emission contribution, water and hydroxyl absorptions are reduced in strength, lowering apparent abundances. It is important to quantify and remove the thermal emission for these reasons. We developed a method for deriving the temperature and emissivity from spectra of the lunar surface and removing the thermal emission in the near infrared. The method is fast enough that it can be applied to imaging spectroscopy data on the Moon. Copyright ?? 2011 by the American Geophysical Union.
Thermal removal from near-infrared imaging spectroscopy data of the Moon
Clark, Roger N.; Pieters, Carle M.; Green, Robert O.; Boardman, J.W.; Petro, Noah E.
2011-01-01
In the near-infrared from about 2 μm to beyond 3 μm, the light from the Moon is a combination of reflected sunlight and emitted thermal emission. There are multiple complexities in separating the two signals, including knowledge of the local solar incidence angle due to topography, phase angle dependencies, emissivity, and instrument calibration. Thermal emission adds to apparent reflectance, and because the emission's contribution increases over the reflected sunlight with increasing wavelength, absorption bands in the lunar reflectance spectra can be modified. In particular, the shape of the 2 μm pyroxene band can be distorted by thermal emission, changing spectrally determined pyroxene composition and abundance. Because of the thermal emission contribution, water and hydroxyl absorptions are reduced in strength, lowering apparent abundances. It is important to quantify and remove the thermal emission for these reasons. We developed a method for deriving the temperature and emissivity from spectra of the lunar surface and removing the thermal emission in the near infrared. The method is fast enough that it can be applied to imaging spectroscopy data on the Moon.
Zibordi, Giuseppe
2016-03-21
Determination of the water-leaving radiance LW through above-water radiometry requires knowledge of accurate reflectance factors ρ of the sea surface. Publicly available ρ relevant to above-water radiometry include theoretical data sets generated: i. by assuming a sky radiance distribution accounting for aerosols and multiple scattering, but neglecting polarization, and quantifying sea surface effects through Cox-Munk wave slope statistics; or differently ii. accounting for polarization, but assuming an ideal Rayleigh sky radiance distribution, and quantifying sea surface effects through modeled wave elevation and slope variance spectra. The impact on above-water data products of differences between those factors ρ was quantified through comparison of LW from the Ocean Color component of the Aerosol Robotic Network (AERONET-OC) with collocated LW from in-water radiometry. Results from the analysis of radiance measurements from the sea performed with 40 degrees viewing angle and 90 degrees azimuth offset with respect to the sun plane, indicated a slightly better agreement between above- and in-water LW determined for wind speeds tentatively lower than 4 m s-1 with ρ computed accounting for aerosols, multiple scattering and Cox-Munk surfaces. Nevertheless, analyses performed by partitioning the investigated data set also indicated that actual ρ values would exhibit dependence on sun zenith comprised between those characterizing the two sets of reflectance factors.
Chromosome catastrophes involve replication mechanisms generating complex genomic rearrangements
Liu, Pengfei; Erez, Ayelet; Sreenath Nagamani, Sandesh C.; Dhar, Shweta U.; Kołodziejska, Katarzyna E.; Dharmadhikari, Avinash V.; Cooper, M. Lance; Wiszniewska, Joanna; Zhang, Feng; Withers, Marjorie A.; Bacino, Carlos A.; Campos-Acevedo, Luis Daniel; Delgado, Mauricio R.; Freedenberg, Debra; Garnica, Adolfo; Grebe, Theresa A.; Hernández-Almaguer, Dolores; Immken, LaDonna; Lalani, Seema R.; McLean, Scott D.; Northrup, Hope; Scaglia, Fernando; Strathearn, Lane; Trapane, Pamela; Kang, Sung-Hae L.; Patel, Ankita; Cheung, Sau Wai; Hastings, P. J.; Stankiewicz, Paweł; Lupski, James R.; Bi, Weimin
2011-01-01
SUMMARY Complex genomic rearrangements (CGR) consisting of two or more breakpoint junctions have been observed in genomic disorders. Recently, a chromosome catastrophe phenomenon termed chromothripsis, in which numerous genomic rearrangements are apparently acquired in one single catastrophic event, was described in multiple cancers. Here we show that constitutionally acquired CGRs share similarities with cancer chromothripsis. In the 17 CGR cases investigated we observed localization and multiple copy number changes including deletions, duplications and/or triplications, as well as extensive translocations and inversions. Genomic rearrangements involved varied in size and complexities; in one case, array comparative genomic hybridization revealed 18 copy number changes. Breakpoint sequencing identified characteristic features, including small templated insertions at breakpoints and microhomology at breakpoint junctions, which have been attributed to replicative processes. The resemblance between CGR and chromothripsis suggests similar mechanistic underpinnings. Such chromosome catastrophic events appear to reflect basic DNA metabolism operative throughout an organism’s life cycle. PMID:21925314
NASA Astrophysics Data System (ADS)
Adibelli, Elif
This qualitative study aimed to explore the changes in elementary science teachers' conceptions of nature of science (NOS) and their beliefs about the developmental appropriateness and importance of NOS after participating in an academic, year-long professional development program (PDP) as well as the factors facilitating these changes. The PDP consisted of two phases. In the first phase, the participants received NOS training designed with an explicit-reflective instructional approach. In the second phase, the participants implemented several NOS training activities in their classrooms. Four elementary science teachers who volunteered and completed all components of the PDP (i.e., the NOS training and the NOS teaching) comprised the participants of the present study. A multiple-embedded case study design was employed to explore the changes in the elementary science teachers' conceptions of NOS and their beliefs about the developmental appropriateness and importance of NOS. The study data were collected from multiple sources. The primary data sources included (a) Views of Nature of Science Elementary School Version 2 (VNOS-D2) questionnaire (Lederman & Khishfe, 2002), (b) Ideas about Science for Early Elementary (K-4) Students questionnaire (Sweeney, 2010), and (c) follow-up semi-structured interviews. The secondary data sources included videotaping of meetings with teachers, reflective field notes, and artifacts produced by teachers and their students. Data were analyzed using Yin's (1994, 2003) analytic tactics of pattern matching, explanation building, and cross-case synthesis. The findings of the study revealed that the elementary science teachers showed gradual, but substantial changes in their conceptions, and beliefs about the developmental appropriateness and importance of the NOS aspects over the course of participation in the PDP. Moreover, the participants identified nine components in the PDP that facilitated these changes in their conceptions, and beliefs about the developmental appropriateness and importance of the NOS aspects. These components were (a) specific focus on the NOS content, (b) participation in hands-on activities on NOS, (c) educational readings on NOS, (d) multiple types/ formats of reflection, (e) multiple exposure to the NOS content, (f) structural consistency in the presentation of the NOS content, (g) the evaluation of secondary student data, (h) the analysis of national and state science standards in terms of NOS, and (i) the implementation of the NOS activities in the classroom. Based on the findings of this study, it may be concluded that explicit-reflective NOS instruction coupled with NOS teaching is sufficient to evolve and crystallize teachers' conceptions and beliefs about the developmental appropriateness and importance of the NOS aspects.
Taking a Risk to Develop Reflective Skills in Business Practitioners
ERIC Educational Resources Information Center
Mackay, Margaret; Tymon, Alex
2016-01-01
Critical reflection can support alternative decision-making in business practice. This paper examines the effectiveness of a risk-based pedagogy to engage practitioners in reflective thinking. Educators adopting a radical pedagogy in professionally accredited programmes face multiple challenges: learners often resist the process of self-reflection…
Kane, Sumit
2016-04-25
This commentary reflects upon the article along three broad lines. It reflects on the theoretical choices and omissions, particularly highlighting why it is important to adapt the multiple streams framework (MSF) when applying it in a socio-political context like Vietnam's. The commentary also reflects upon the analytical threads tackled by Ha et al; for instance, it highlights the opportunities offered by, and raises questions about the centrality of the Policy Entrepreneur in getting the policy onto the political agenda and in pushing it through. The commentary also dwells on the implications of the article for development aid policies and practices. Throughout, the commentary signposts possible themes for Ha et al to consider for further analysis, and more generally, for future research using Kingdon's multiple streams theory. © 2016 by Kerman University of Medical Sciences.
Waveform modeling of the seismic response of a mid-ocean ridge axial melt sill
NASA Astrophysics Data System (ADS)
Xu, Min; Stephen, R. A.; Canales, J. Pablo
2017-12-01
Seismic reflections from axial magma lens (AML) are commonly observed along many mid-ocean ridges, and are thought to arise from the negative impedance contrast between a solid, high-speed lid and the underlying low-speed, molten or partially molten (mush) sill. The polarity of the AML reflection ( P AML P) at vertical incidence and the amplitude vs offset (AVO) behavior of the AML reflections (e.g., P AML P and S-converted P AML S waves) are often used as a diagnostic tool for the nature of the low-speed sill. Time-domain finite difference calculations for two-dimensional laterally homogeneous models show some scenarios make the interpretation of melt content from partial-offset stacks of P- and S-waves difficult. Laterally heterogeneous model calculations indicate diffractions from the edges of the finite-width AML reducing the amplitude of the AML reflections. Rough seafloor and/or a rough AML surface can also greatly reduce the amplitude of peg-leg multiples because of scattering and destructive interference. Mid-crustal seismic reflection events are observed in the three-dimensional multi-channel seismic dataset acquired over the RIDGE-2000 Integrated Study Site at East Pacific Rise (EPR, cruise MGL0812). Modeling indicates that the mid-crustal seismic reflection reflections are unlikely to arise from peg-leg multiples of the AML reflections, P-to- S converted phases, or scattering due to rough topography, but could probably arise from deeper multiple magma sills. Our results support the identification of Marjanović et al. (Nat Geosci 7(11):825-829, 2014) that a multi-level complex of melt lenses is present beneath the axis of the EPR.
NASA Astrophysics Data System (ADS)
Sullivan, F.; Ollinger, S. V.; Palace, M. W.; Ouimette, A.; Sanders-DeMott, R.; Lepine, L. C.
2017-12-01
The correlation between near-infrared reflectance and forest canopy nitrogen concentration has been demonstrated at varying scales using a range of optical sensors on airborne and satellite platforms. Although the mechanism underpinning the relationship is unclear, at its basis are biologically-driven functional relationships of multiple plant traits that affect canopy chemistry and structure. The link between near-infrared reflectance and canopy nitrogen has been hypothesized to be partially driven by covariation of canopy nitrogen with canopy structure. In this study, we used a combination of airborne LiDAR data and field measured leaf and canopy chemical and structural traits to explore interrelationships between canopy nitrogen, near-infrared reflectance, and canopy structure on plots at Bartlett Experimental Forest in the White Mountain National Forest, New Hampshire. Over each plot, we developed a 1-meter resolution canopy height profile and a 1-meter resolution canopy height model. From canopy height profiles and canopy height models, we calculated a set of metrics describing the plot-level variability, breadth, depth, and arrangement of LiDAR returns. This combination of metrics was used to describe both vertical and horizontal variation in structure. In addition, we developed and measured several field-based metrics of leaf and canopy structure at the plot scale by directly measuring the canopy or by weighting leaf-level metrics by species leaf area contribution. We assessed relationships between leaf and structural metrics, near-infrared reflectance and canopy nitrogen concentration using multiple linear regression and mixed effects modeling. Consistent with our hypothesis, we found moderately strong links between both near-infrared reflectance and canopy nitrogen concentration with LiDAR-derived structural metrics, and we additionally found that leaf-level metrics scaled to the plot level share an important role in canopy reflectance. We suggest that canopy structure has a governing role in canopy reflectance, reducing maximum potential reflectance as structural complexity increases, and therefore also influences the relationship between canopy nitrogen and NIR reflectance.
McMullen, Carmit K; Luborsky, Mark R
2006-08-01
We explored self-rated health by using a meaning-centered theoretical foundation. Self-appraisals, such as self-rated health, reflect a cultural process of identity formation, whereby identities are multiple, simultaneously individual and collective, and produced by specific historical formations. Anthropological research in Philadelphia determined (a) how African American elders appraise their health, and (b) how health evaluations reflect cultural and historical experiences within a community. We interviewed and observed 35 adults aged 65 to 80, stratified by gender and self-rated health. We validated theme analysis of focused interview questions against the larger data set of field notes and transcripts. Health appraisal reflected a complex process of adaptation and identity. Criteria for health included: independent functioning, physical condition, control and responsibility for health, and overall feeling. Evaluative rationales that shaped health appraisals were comparisons, restricted possibilities for self-evaluation, and ways of handling adversity. Evaluative rationales mitigated undesirable health identities (including low self-reported health) and provided mechanisms for claiming desired health identities despite adversity. Describing the criteria and evaluative rationales underlying self-appraisals of health extends current understandings of self-rated health and illustrates the sociohistorical context of individual assessments of well-being.
Crossed beam roof target for motion tracking
NASA Technical Reports Server (NTRS)
Olczak, Eugene (Inventor)
2009-01-01
A system for detecting motion between a first body and a second body includes first and second detector-emitter pairs, disposed on the first body, and configured to transmit and receive first and second optical beams, respectively. At least a first optical rotator is disposed on the second body and configured to receive and reflect at least one of the first and second optical beams. First and second detectors of the detector-emitter pairs are configured to detect the first and second optical beams, respectively. Each of the first and second detectors is configured to detect motion between the first and second bodies in multiple degrees of freedom (DOFs). The first optical rotator includes a V-notch oriented to form an apex of an isosceles triangle with respect to a base of the isosceles triangle formed by the first and second detector-emitter pairs. The V-notch is configured to receive the first optical beam and reflect the first optical beam to both the first and second detectors. The V-notch is also configured to receive the second optical beam and reflect the second optical beam to both the first and second detectors.
Red edge spectral measurements from sugar maple leaves
NASA Technical Reports Server (NTRS)
Vogelmann, J. E.; Rock, B. N.; Moss, D. M.
1993-01-01
Many sugar maple stands in the northeastern United States experienced extensive insect damage during the 1988 growing season. Chlorophyll data and high spectral resolution spectrometer laboratory reflectance data were acquired for multiple collections of single detached sugar maple leaves variously affected by the insect over the 1988 growing season. Reflectance data indicated consistent and diagnostic differences in the red edge portion (680-750 nm) of the spectrum among the various samples and populations of leaves. These included differences in the red edge inflection point (REIP), a ratio of reflectance at 740-720 nm (RE3/RE2), and a ratio of first derivative values at 715-705 nm (D715/D705). All three red edge parameters were highly correlated with variation in total chlorophyll content. Other spectral measures, including the Normalized Difference Vegetation Index (NDVI) and the Simple Vegetation Index Ratio (VI), also varied among populations and over the growing season, but did not correlate well with total chlorophyll content. Leaf stacking studies on light and dark backgrounds indicated REIP, RE3/RE2 and D715/D705 to be much less influenced by differences in green leaf biomass and background condition than either NDVI or VI.
Seismic multiple attenuation in the northern continent-ocean transition zone of the South China Sea
NASA Astrophysics Data System (ADS)
Chen, N.; Li, C. F.
2017-12-01
In seismic exploration, especially in marine oil and gas exploration, presence of multiple reflections lowers signal-to-noise ratio of seismic data and makes it difficult to analyze seismic velocity. In northern continent-ocean transition zone of the South China Sea (SCS), low-velocity Cenozoic strata cover sets of high-velocity carbonate strata directly, and over 1000 m thick of sediments were deposited on the igneous basement in the northwest SCS. These sedimentary boundaries generate quite strong impedance interfaces and strong internal multiples. Diffractions as a result of variation of seabed topography, coupled with the vibration, free surface multiples and refraction multiples, cause a variety of strong energy disturbances and missing of frequency component. In this study, we process four recently acquired multichannel reflection seismic profiles from the northern continent-ocean transition zone of the SCS with a new combination of demultiple techniques. There is a variety of strong multiples in the raw data, and the seabed multiple occurs between 9 to 11 seconds in two-way travel time (TWTT), and we apply Surface-related Multiple Elimination (SRME) to attenuate the free surface multiples. After SRME, we use high-resolution Radon transform (RAMUR) to attenuate deep multiples concentrating below 10 seconds in TWTT. Normal moveout correction (NMO) is necessary to flatten true reflections and turn multiples into a parabola before RAMUR, and we can attenuate the deep multiples in theτ-p domain. The seabed topography varies greatly in the continent-ocean transition zone, so the diffractions are well developed. However, SRME and RAMUR are not effective in attenuating diffractions and internal multiples. We select diffracted multiple attenuation (DIMAT) after many trials and detailed analysis. The diffractions are extracted in decomposed frequency bands. The internal multiples below 11 seconds in TWTT and high-amplitude noises are successfully suppressed while keeping the primary events. This combination of SRME, RAMUR and DIMAT in sequence demonstrates to be quite effective in attenuating these types of multiples on the continent-ocean transition zone. Keywords: Continent-ocean transition zone, seismic exploration, data processing, multiple attenuation
Vertical Photon Transport in Cloud Remote Sensing Problems
NASA Technical Reports Server (NTRS)
Platnick, S.
1999-01-01
Photon transport in plane-parallel, vertically inhomogeneous clouds is investigated and applied to cloud remote sensing techniques that use solar reflectance or transmittance measurements for retrieving droplet effective radius. Transport is couched in terms of weighting functions which approximate the relative contribution of individual layers to the overall retrieval. Two vertical weightings are investigated, including one based on the average number of scatterings encountered by reflected and transmitted photons in any given layer. A simpler vertical weighting based on the maximum penetration of reflected photons proves useful for solar reflectance measurements. These weighting functions are highly dependent on droplet absorption and solar/viewing geometry. A superposition technique, using adding/doubling radiative transfer procedures, is derived to accurately determine both weightings, avoiding time consuming Monte Carlo methods. Superposition calculations are made for a variety of geometries and cloud models, and selected results are compared with Monte Carlo calculations. Effective radius retrievals from modeled vertically inhomogeneous liquid water clouds are then made using the standard near-infrared bands, and compared with size estimates based on the proposed weighting functions. Agreement between the two methods is generally within several tenths of a micrometer, much better than expected retrieval accuracy. Though the emphasis is on photon transport in clouds, the derived weightings can be applied to any multiple scattering plane-parallel radiative transfer problem, including arbitrary combinations of cloud, aerosol, and gas layers.
McStas event logger: Definition and applications
NASA Astrophysics Data System (ADS)
Bergbäck Knudsen, Erik; Bryndt Klinkby, Esben; Kjær Willendrup, Peter
2014-02-01
Functionality is added to the McStas neutron ray-tracing code, which allows individual neutron states before and after a scattering to be temporarily stored, and analysed. This logging mechanism has multiple uses, including studies of longitudinal intensity loss in neutron guides and guide coating design optimisations. Furthermore, the logging method enables the cold/thermal neutron induced gamma background along the guide to be calculated from the un-reflected neutron, using a recently developed MCNPX-McStas interface.
Optic probe for multiple angle image capture and optional stereo imaging
Malone, Robert M.; Kaufman, Morris I.
2016-11-29
A probe including a multiple lens array is disclosed to measure velocity distribution of a moving surface along many lines of sight. Laser light, directed to the moving surface is reflected back from the surface and is Doppler shifted, collected into the array, and then directed to detection equipment through optic fibers. The received light is mixed with reference laser light and using photonic Doppler velocimetry, a continuous time record of the surface movement is obtained. An array of single-mode optical fibers provides an optic signal to the multiple lens array. Numerous fibers in a fiber array project numerous rays to establish many measurement points at numerous different locations. One or more lens groups may be replaced with imaging lenses so a stereo image of the moving surface can be recorded. Imaging a portion of the surface during initial travel can determine whether the surface is breaking up.
Reflections on Native Ethnography by a Nurse Researcher.
Abdulrehman, Munib Said
2017-03-01
There are benefits and challenges associated with conducting research in a familiar setting, especially when the researcher is more an insider than an outsider. The aim of this article is to explore the author's experience as a native scholar conducting ethnographic research among the Swahili peoples of Lamu, Kenya. This article focuses on methodological issues related to conducting ethnographic research among the author's own people, including examining the issues of anthropological reflexivity as a native ethnographer and highlighting the author's experiences embodying multiple identities. Native ethnographers must consider the challenges associated with negotiating multiple roles in the research setting, especially in the presence of sociocultural factors such as gender stratification, complex kinship networks, socioeconomic hierarchies, illiteracy, and poverty. Embracing rather than being confused by the multiple levels of understanding native researchers bring to studies of their communities opens up new avenues of research and possibilities.
Consistent radiative transfer modeling of active and passive observations of precipitation
NASA Astrophysics Data System (ADS)
Adams, Ian
2016-04-01
Spaceborne platforms such as the Tropical Rainfall Measurement Mission (TRMM) and the Global Precipitation Measurement (GPM) mission exploit a combination of active and passive sensors to provide a greater understanding of the three-dimensional structure of precipitation. While "operationalized" retrieval algorithms require fast forward models, the ability to perform higher fidelity simulations is necessary in order to understand the physics of remote sensing problems by testing assumptions and developing parameterizations for the fast models. To ensure proper synergy between active and passive modeling, forward models must be consistent when modeling the responses of radars and radiometers. This work presents a self-consistent transfer model for simulating radar reflectivities and millimeter wave brightness temperatures for precipitating scenes. To accomplish this, we extended the Atmospheric Radiative Transfer Simulator (ARTS) version 2.3 to solve the radiative transfer equation for active sensors and multiple scattering conditions. Early versions of ARTS (1.1) included a passive Monte Carlo solver, and ARTS is capable of handling atmospheres of up to three dimensions with ellipsoidal planetary geometries. The modular nature of ARTS facilitates extensibility, and the well-developed ray-tracing tools are suited for implementation of Monte Carlo algorithms. Finally, since ARTS handles the full Stokes vector, co- and cross-polarized reflectivity products are possible for scenarios that include nonspherical particles, with or without preferential alignment. The accuracy of the forward model will be demonstrated with precipitation events observed by TRMM and GPM, and the effects of multiple scattering will be detailed. The three-dimensional nature of the radiative transfer model will be useful for understanding the effects of nonuniform beamfill and multiple scattering for spatially heterogeneous precipitation events. The targets of this forward model are GPM (the Dual-wavelength Precipitation Radar (DPR) and GPM Microwave Imager (GMI)).
NASA Astrophysics Data System (ADS)
Messina, Piero; Foing, Bernard H.; Hufenbach, Bernhard; Haignere, Claudie; Schrogl, Kai-Uwe
2016-07-01
The "Moon Village" concept Space exploration is anchored in the International Space Station and in the current and future automatic and planetary automatic and robotic missions that pave the way for future long-term exploration objectives. The Moon represents a prime choice for scientific, operational and programmatic reasons and could be the enterprise that federates all interested Nations. On these considerations ESA is currently elaborating the concept of a Moon Village as an ensemble where multiple users can carry out multiple activities. The Moon Village has the ambition to serve a number of objectives that have proven to be of interest (including astronomy, fundamental research, resources management, moon science, etc. ) to the space community and should be the catalyst of new alliances between public and private entities including non-space industries. Additionally the Moon Village should provide a strong inspirational and education tool for the younger generations . The Moon Village will rely both on automatic, robotic and human-tendered structures to achieve sustainable moon surface operations serving multiple purposes on an open-architecture basis. This Europe-inspired initiative should rally all communities (across scientific disciplines, nations, industries) and make it to the top of the political agendas as a the scientific and technological undertaking but also political and inspirational endeavour of the XXI century. The current reflections are of course based on the current activities and plans on board the ISS and the discussion held in international fora such as the ISECG. The paper will present the status of these reflections, also in view of the ESA Council at Ministerial Level 2016, and will give an overview of the on-going activities being carried out to enable the vision of a Moon Village.
Space Object Classification and Characterization Via Multiple Model Adaptive Estimation
2014-07-14
BRDF ) which models light distribution scattered from the surface due to the incident light. The BRDF at any point on the surface is a function of two...uu B vu B nu obs I u sun I u I hu (b) Reflection Geometry Fig. 2: Reflection Geometry and Space Object Shape Model of the BRDF is ρdiff(i...Space Object Classification and Characterization Via Multiple Model Adaptive Estimation Richard Linares Director’s Postdoctoral Fellow Space Science
Very High Reflectivity Supermirrors And Their Applications
NASA Astrophysics Data System (ADS)
Mezei, F.
1989-01-01
Very high reflectivity (some 95 % or better) supermirrors, with cut-off angles up to 2 times the critical angle of Ni coated simple total reflection neutron mirrors, can be produced using well established conventional deposition techniques. This performance makes applications involving multiple reflections and transmission geometries feasible, which in turn allow us to use more sophisticated neutron optical systems in order to optimize performance and minimize the amount a scarce supermirrors required. A key feature of several of these novel systems is the distribution of tasks between the several optical components achieving the desired performance by multiple action. The design and characteristics of a series of novel applications, such as polarizing cavities, collimators and guides, non-polarizing guides, beam compressors, deflectors and splitters (most of them tested or being implemented) are the main subjects of the present paper.
Beaudoin, Bruce C.; ten Brink, Uri S.; Stern, Tim A.
1992-01-01
Coincident reflection and refraction data, collected in the austral summer of 1988/89 by Stanford University and the Geophysical Division of the Department of Scientific and Industrial Research, New Zealand, imaged the crust beneath the Ross Ice Shelf, Antarctica. The Ross Ice Shelf is a unique acquisition environment for seismic reflection profiling because of its thick, floating ice cover. The ice shelf velocity structure is multilayered with a high velocity‐gradient firn layer constituting the upper 50 to 100 m. This near surface firn layer influences the data character by amplifying and frequency modulating the incoming wavefield. In addition, the ice‐water column introduces pervasive, high energy seafloor, intra‐ice, and intra‐water multiples that have moveout velocities similar to the expected subseafloor primary velocities. Successful removal of these high energy multiples relies on predictive deconvolution, inverse velocity stack filtering, and frequency filtering. Removal of the multiples reveals a faulted, sedimentary wedge which is truncated at or near the seafloor. Beneath this wedge the reflection character is diffractive to a two‐way traveltime of ∼7.2 s. At this time, a prominent reflection is evident on the southeast end of the reflection profile. This reflection is interpreted as Moho indicating that the crust is ∼21-km thick beneath the profile. These results provide seismic evidence that the extensional features observed in the Ross Sea region of the Ross Embayment extend beneath the Ross Ice Shelf.
Memory and other properties of multiple test procedures generated by entangled graphs.
Maurer, Willi; Bretz, Frank
2013-05-10
Methods for addressing multiplicity in clinical trials have attracted much attention during the past 20 years. They include the investigation of new classes of multiple test procedures, such as fixed sequence, fallback and gatekeeping procedures. More recently, sequentially rejective graphical test procedures have been introduced to construct and visualize complex multiple test strategies. These methods propagate the local significance level of a rejected null hypothesis to not-yet rejected hypotheses. In the graph defining the test procedure, hypotheses together with their local significance levels are represented by weighted vertices and the propagation rule by weighted directed edges. An algorithm provides the rules for updating the local significance levels and the transition weights after rejecting an individual hypothesis. These graphical procedures have no memory in the sense that the origin of the propagated significance level is ignored in subsequent iterations. However, in some clinical trial applications, memory is desirable to reflect the underlying dependence structure of the study objectives. In such cases, it would allow the further propagation of significance levels to be dependent on their origin and thus reflect the grouped parent-descendant structures of the hypotheses. We will give examples of such situations and show how to induce memory and other properties by convex combination of several individual graphs. The resulting entangled graphs provide an intuitive way to represent the underlying relative importance relationships between the hypotheses, are as easy to perform as the original individual graphs, remain sequentially rejective and control the familywise error rate in the strong sense. Copyright © 2012 John Wiley & Sons, Ltd.
Fusing chlorophyll fluorescence and plant canopy reflectance to detect TNT contamination in soils
NASA Astrophysics Data System (ADS)
Naumann, Julie C.; Rubis, Kathryn; Young, Donald R.
2010-04-01
TNT is released into the soil from many different sources, especially from military and mining activities, including buried land mines. Vegetation may absorb explosive residuals, causing stress and by understanding how plants respond to energetic compounds, we may be able to develop non-invasive techniques to detect soil contamination. The objectives of our study were to examine the physiological response of plants grown in TNT contaminated soils and to use remote sensing methods to detect uptake in plant leaves and canopies in both laboratory and field studies. Differences in physiology and light-adapted fluorescence were apparent in laboratory plants grown in N enriched soils and when compared with plants grown in TNT contaminated soils. Several reflectance indices were able to detect TNT contamination prior to visible signs of stress, including the fluorescence-derived indices, R740/R850 and R735/R850, which may be attributed to transformation and conjugation of TNT metabolites with other compounds. Field studies at the Duck, NC Field Research Facility revealed differences in physiological stress measures, and leaf and canopy reflectance when plants growing over suspected buried UXOs were compared with reference plants. Multiple reflectance indices indicated stress at the suspected contaminated sites, including R740/R850 and R735/R850. Under natural conditions of constant leaching of TNT into the soil, TNT uptake would be continuous in plants, potentially creating a distinct signature from remotely sensed vegetation. We may be able to use remote sensing of plant canopies to detect TNT soil contamination prior to visible signs.
Optically controlled reflection modulator using GaAs-AlGaAs n-i-p-i/multiple-quantum-well structures
NASA Technical Reports Server (NTRS)
Law, K.-K.; Simes, R. J.; Coldren, L. A.; Gossard, A. C.; Maserjian, J.
1989-01-01
An optically controlled reflection modulator has been demonstrated that consists of a combination of a GaAs-AlGaAs n-i-p-i doping structure with a multiple-quantum-well structures on top of a distributed Bragg reflector, all grown by MBE. A modulation of approximately 60 percent is obtained on the test structure, corresponding to a differential change of absorption coefficient in the quantum wells of approximately 7500/cm. Changes in reflectance can be observed with a control beam power as low as 1.5 microW. This device structure has the potential of being developed as an optically addressed spatial light modulator for optical information processing.
NASA Astrophysics Data System (ADS)
Bolshakov, A. S.; Chaldyshev, V. V.; Zavarin, E. E.; Sakharov, A. V.; Lundin, W. V.; Tsatsulnikov, A. F.; Yagovkina, M. A.
2017-04-01
We studied the optical properties of periodic InGaN/GaN multiple quantum well systems with different numbers of periods. A resonant increase in the optical reflection and simultaneous suppression of the optical absorption have been revealed experimentally at room temperature when the Bragg and exciton resonances were tuned to each other. Numerical modeling with a single set of parameters gave a quantitatively accurate fit of the experimental reflection and transmission spectra in a wide wavelength range and various angles of the light incidence. The model included both exciton resonance and non-resonant band-to-band transitions in the InGaN quantum wells, as well as Rayleigh light scattering in the GaN buffer layer. The analysis also involved x-ray diffraction and photoluminescence data. It allowed us to determine the key parameters of the structure. In particular, the radiative broadening of the InGaN QW excitons was evaluated as 0.20 ± 0.02 meV.
Transverse strain measurements using fiber optic grating based sensors
NASA Technical Reports Server (NTRS)
Udd, Eric (Inventor)
1998-01-01
A system and method to sense the application of transverse stress to an optical fiber which includes a light source that producing a relatively wide spectrum light beam. The light beam is reflected or transmitted off of an optical grating in the core of an optical fiber that is transversely stressed either directly or by the exposure to pressure when the fiber is bifringent so that the optical fiber responds to the pressure to transversely stress its core. When transversely stressed, the optical grating produces a reflection or transmission from the light beam that has two peaks or minimums in its frequency spectrum whose spacing and/or spread are indicative of the forces applied to the fiber. One or more detectors sense the reflection or transmissions from the optical grating to produce an output representative of the applied force. Multiple optical gratings and detectors may be employed to simultaneously measure temperature or the forces at different locations along the fiber.
SuperADAM: Upgraded polarized neutron reflectometer at the Institut Laue-Langevin
DOE Office of Scientific and Technical Information (OSTI.GOV)
Devishvili, A.; Zhernenkov, K.; Institut Laue-Langevin, BP 156, 38042 Grenoble
2013-02-15
A new neutron reflectometer SuperADAM has recently been built and commissioned at the Institut Laue-Langevin, Grenoble, France. It replaces the previous neutron reflectometer ADAM. The new instrument uses a solid state polarizer/wavelength filter providing a highly polarized (up to 98.6%) monochromatic neutron flux of 8 Multiplication-Sign 10{sup 4} n cm{sup -2} s{sup -1} with monochromatization {Delta}{lambda}/{lambda}= 0.7% and angular divergence {Delta}{alpha}= 0.2 mrad. The instrument includes both single and position sensitive detectors. The position sensitive detector allows simultaneous measurement of specular reflection and off-specular scattering. Polarization analysis for both specular reflection and off-specular scattering is achieved using either mirror analyzersmore » or a {sup 3}He spin filter cell. High efficiency detectors, low background, and high flux provides a dynamic range of up to seven decades in reflectivity. Detailed specifications and the instrument capabilities are illustrated with examples of recently collected data in the fields of thin film magnetism and thin polymer films.« less
Lamp method and apparatus using multiple reflections
MacLennan, Donald A.; Turner, Brian P.
2001-01-01
An electrodeless microwave discharge lamp includes an envelope with a discharge forming fill disposed therein which emits light, the fill being capable of absorbing light at one wavelength and re-emitting the absorbed light at a different wavelength, the light emitted from the fill having a first spectral power distribution in the absence of reflection of light back into the fill, a source of microwave energy coupled to the fill to excite the fill and cause the fill to emit light, and a reflector disposed within the microwave cavity and configured to reflect at least some of the light emitted by the fill back into the fill while allowing some light to exit, the exiting light having a second spectral power distribution with proportionately more light in the visible region as compared to the first spectral power distribution, wherein the light re-emitted by the fill is shifted in wavelength with respect to the absorbed light and the magnitude of the shift is in relation to an effective optical path length.
NASA Astrophysics Data System (ADS)
Lin, Jia-De; Lin, Hong-Lin; Lin, Hsin-Yu; Wei, Guan-Jhong; Lee, Chia-Rong
2017-02-01
The scientists in the field of liquid crystal (LC) have paid significant attention in the exploration of novel cholesteric LC (CLC) polymer template (simply called template) in recent years. The self-assembling nanostructural template with chirality can effectively overcome the limitation in the optical features of traditional CLCs, such as enhancement of reflectivity over 50%, multiple photonic bandgaps (PBGs), and changeable optical characteristics by flexibly replacing the refilling LC materials, and so on. This work fabricates two gradient-pitched CLC templates with two opposite handednesses, which are then merged as a spatially tunable and highly reflective CLC template sample. This sample can simultaneously reflect right- and left-circularly polarized lights and the tunable spectral range includes the entire visible region. By increasing the temperature of the template sample exceeding the clearing point of the refilling LC, the light scattering significantly decreases and the reflectance effectively increase to exceed 50% in the entire visible region. This device has a maximum reflectance over 85% and a wide-band spatial tunability in PBG between 400 nm and 800 nm which covers the entire visible region. Not only the sample can be employed as a wide-band spatially tunable filter, but also the system doping with two suitable laser dyes which emitted fluorescence can cover entire visible region can develop a low-threshold, mirror-less laser with a spatial tunability at spectral regions including blue to red region (from 484 nm to 634 nm) and simultaneous lasing emission of left- and right-circular polarizations.
Levin, Robert E.; English, George J.
1986-08-05
An infrared floodlight assembly designed particularly for security purposes and including a heat-conducting housing, a lens secured to the housing to provide a closure therefor, and a floodlight located within (and surrounded by) the housing. The floodlight combines the use of a tungsten halogen light source and dichroic hot and cold mirrors for directing substantially only infrared radiation toward the assembly's forward lens. Visible radiation is absorbed by the housing's interior wall(s) and, optionally, by a filter located between the floodlight and lens. An optional means may be used within the floodlight to reflect all forward radiation back toward the paraboloidal hot mirror or, alternatively, to reflect only visible radiation in this direction. The dichroic hot and cold mirrors preferably each comprise a glass substrate having multiple layers of titanium dioxide and silicon dioxide thereon.
Sela, D. A.; Chapman, J.; Adeuya, A.; Kim, J. H.; Chen, F.; Whitehead, T. R.; Lapidus, A.; Rokhsar, D. S.; Lebrilla, C. B.; German, J. B.; Price, N. P.; Richardson, P. M.; Mills, D. A.
2008-01-01
Following birth, the breast-fed infant gastrointestinal tract is rapidly colonized by a microbial consortium often dominated by bifidobacteria. Accordingly, the complete genome sequence of Bifidobacterium longum subsp. infantis ATCC15697 reflects a competitive nutrient-utilization strategy targeting milk-borne molecules which lack a nutritive value to the neonate. Several chromosomal loci reflect potential adaptation to the infant host including a 43 kbp cluster encoding catabolic genes, extracellular solute binding proteins and permeases predicted to be active on milk oligosaccharides. An examination of in vivo metabolism has detected the hallmarks of milk oligosaccharide utilization via the central fermentative pathway using metabolomic and proteomic approaches. Finally, conservation of gene clusters in multiple isolates corroborates the genomic mechanism underlying milk utilization for this infant-associated phylotype. PMID:19033196
The propagation of sound in narrow street canyons
NASA Astrophysics Data System (ADS)
Iu, K. K.; Li, K. M.
2002-08-01
This paper addresses an important problem of predicting sound propagation in narrow street canyons with width less than 10 m, which are commonly found in a built-up urban district. Major noise sources are, for example, air conditioners installed on building facades and powered mechanical equipment for repair and construction work. Interference effects due to multiple reflections from building facades and ground surfaces are important contributions in these complex environments. Although the studies of sound transmission in urban areas can be traced back to as early as the 1960s, the resulting mathematical and numerical models are still unable to predict sound fields accurately in city streets. This is understandable because sound propagation in city streets involves many intriguing phenomena such as reflections and scattering at the building facades, diffusion effects due to recessions and protrusions of building surfaces, geometric spreading, and atmospheric absorption. This paper describes the development of a numerical model for the prediction of sound fields in city streets. To simplify the problem, a typical city street is represented by two parallel reflecting walls and a flat impedance ground. The numerical model is based on a simple ray theory that takes account of multiple reflections from the building facades. The sound fields due to the point source and its images are summed coherently such that mutual interference effects between contributing rays can be included in the analysis. Indoor experiments are conducted in an anechoic chamber. Experimental data are compared with theoretical predictions to establish the validity and usefulness of this simple model. Outdoor experimental measurements have also been conducted to further validate the model. copyright 2002 Acoustical Society of America.
NASA Astrophysics Data System (ADS)
Pongsanon, Khemmawadee
Although teacher educators have successfully helped K-12 teachers' develop adequate views of NOS, their views have not been transferred to their students. It is evident that K-12 students' understanding of NOS still does not align with the recommendation of the reforms document, indicating that holding an adequate view of NOS is insufficient for teaching NOS effectively. Instead, to teach NOS, teachers must develop the knowledge for translating their understanding of NOS into the forms accessible to students. The current study investigated the influence of four contexts of reflective practice on prospective elementary teachers' learning of how and intention to teach NOS. The participants were 18 pre-service teachers enrolled in a science methods course that was tied to a field experience course. To understand the development of the participants' intentions, knowledge of instructional strategies, and knowledge of assessment for teaching NOS, multiple data were collected throughout the science methods course and the field experience. Data sources included different versions of participants' lesson plans, video recordings of their teaching and teaching debriefings, online weekly teaching reflections, final semester reflection and other artifacts from the methods course. Content analysis was conducted with all data. The data revealed that the participants' knowledge of how and intentions to teach NOS were developed throughout the science methods course. Toward the conclusion of the semester, the participants showed intention to include NOS in their science instruction. With regard to strategies, participants planned to apply explicit reflective NOS instruction in the context of inquiry-based activities and stories from children's literature. They also planned to use age-appropriate language to refer to the targeted NOS aspects. In terms of assessment, by the conclusion of the semester the participants tended to use more formal assessment strategies. They reported reflections on experiences from modeled lessons and their own teaching as most influential on such development. Implications of the study include applying the four contexts of reflection to help future elementary teachers develop the components of PCK for teaching NOS.
Ludwig, V; Mihov, Y; Schwarting, R K W
2008-05-16
Using the elevated plus-maze (EPM), Wistar rats can be distinguished into high (HA) or low anxiety (LA) subjects. These differences seem to reflect traits, since HA and LA rats vary also in other anxiety-dependent tasks, neurochemical mechanisms, and psychopharmacological reactivity, including lasting consequences after single treatment with 3,4-methylenedioxymethamphetamine (MDMA). Here, we tested whether multiple MDMA treatments also have subject-dependent effects. Based on routine EPM screening, male Wistar rats were divided into HA and LA sub-groups, which received five (i.e. multiple) daily injections of MDMA (5 mg/kg) or saline, followed by a test battery, including a challenge test with MDMA, a retest in the EPM, a novel-object test, and a final neurochemical analysis. Acutely, MDMA led to comparable hyperactivity in HA and LA rats. After multiple MDMA, behavioral sensitization was observed, especially in LA rats. Open arm time during the EPM retest (min 0-5) correlated with that of the initial one only in those rats, which had received a single injection of MDMA. Rats with multiple MDMA, especially LA-rats, showed more open-arm time and locomotion during the subsequent 5-10 min of the retest. In a novel-object test, rats with multiple MDMA, again especially LA subjects, showed more exploratory bouts towards the novel object. Neurochemically, multiple MDMA led to moderately lower serotonin in the ventral striatum, and higher dopamine levels in the frontal cortex as compared to single MDMA; these effects were also moderated by subject-dependent factors. Our data show that low-dosed multiple MDMA can lead to behavioral sensitization and outlasting consequences, which affect behavior in the EPM and a novel object task. Detecting such sequels partly requires consideration of individual differences.
Georgopoulos, Michael; Zehetmayer, Martin; Ruhswurm, Irene; Toma-Bstaendig, Sabine; Ségur-Eltz, Nikolaus; Sacu, Stefan; Menapace, Rupert
2003-01-01
This study assesses differences in relative tumour regression and internal acoustic reflectivity after 3 methods of radiotherapy for uveal melanoma: (1) brachytherapy with ruthenium-106 radioactive plaques (RU), (2) fractionated high-dose gamma knife stereotactic irradiation in 2-3 fractions (GK) or (3) fractionated linear-accelerator-based stereotactic teletherapy in 5 fractions (Linac). Ultrasound measurements of tumour thickness and internal reflectivity were performed with standardised A scan pre-operatively and 3, 6, 9, 12, 18, 24 and 36 months postoperatively. Of 211 patients included in the study, 111 had a complete 3-year follow-up (RU: 41, GK: 37, Linac: 33). Differences in tumour thickness and internal reflectivity were assessed with analysis of variance, and post hoc multiple comparisons were calculated with Tukey's honestly significant difference test. Local tumour control was excellent with all 3 methods (>93%). At 36 months, relative tumour height reduction was 69, 50 and 30% after RU, GK and Linac, respectively. In all 3 treatment groups, internal reflectivity increased from about 30% initially to 60-70% 3 years after treatment. Brachytherapy with ruthenium-106 plaques results in a faster tumour regression as compared to teletherapy with gamma knife or Linac. Internal reflectivity increases comparably in all 3 groups. Besides tumour growth arrest, increasing internal reflectivity is considered as an important factor indicating successful treatment. Copyright 2003 S. Karger AG, Basel
Baksi, A John; Davies, Justin E; Hadjiloizou, Nearchos; Baruah, Resham; Unsworth, Beth; Foale, Rodney A; Korolkova, Olga; Siggers, Jennifer H; Francis, Darrel P; Mayet, Jamil; Parker, Kim H; Hughes, Alun D
2016-01-01
Wave reflection may be an important influence on blood pressure, but the extent to which reflections undergo attenuation during retrograde propagation has not been studied. We quantified retrograde transmission of a reflected wave created by occlusion of the left femoral artery in man. 20 subjects (age 31-83 years; 14 male) underwent invasive measurement of pressure and flow velocity with a sensor-tipped intra-arterial wire at multiple locations distal to the proximal aorta before, during and following occlusion of the left femoral artery by thigh cuff inflation. A numerical model of the circulation was also used to predict reflected wave transmission. Wave reflection was measured as the ratio of backward to forward wave energy (WRI) and the ratio of peak backward to forward pressure (Pb/Pf). Cuff inflation caused a marked reflection which was largest at 5-10 cm from the cuff (change (Δ) in WRI=0.50 (95% CI 0.38, 0.62); p<0.001, ΔPb/Pf=0.23 (0.18-0.29); p<0.001). The magnitude of the cuff-induced reflection decreased progressively at more proximal locations and was barely discernible at sites>40 cm from the cuff including in the proximal aorta. Numerical modelling gave similar predictions to those observed experimentally. Reflections due to femoral artery occlusion are markedly attenuated by the time they reach the proximal aorta. This is due to impedance mismatches of bifurcations traversed in the backward direction. This degree of attenuation is inconsistent with the idea of a large discrete reflected wave arising from the lower limb and propagating back into the aorta. Copyright © 2015. Published by Elsevier Ireland Ltd.
Zhang, Sharon; Ratliff, Eric P.; Molina, Brandon; El-Mecharrafie, Nadja; Mastroianni, Jessica; Kotzebue, Roxanne W.; Achal, Madhulika; Mauntz, Ruth E.; Gonzalez, Arysa; Barekat, Ayeh; Bray, William A.; Macias, Andrew M.; Daugherty, Daniel; Harris, Greg L.; Edwards, Robert A.; Finley, Kim D.
2018-01-01
The progressive decline of the nervous system, including protein aggregate formation, reflects the subtle dysregulation of multiple functional pathways. Our previous work has shown intermittent fasting (IF) enhances longevity, maintains adult behaviors and reduces aggregates, in part, by promoting autophagic function in the aging Drosophila brain. To clarify the impact that IF-treatment has upon aging, we used high throughput RNA-sequencing technology to examine the changing transcriptome in adult Drosophila tissues. Principle component analysis (PCA) and other analyses showed ~1200 age-related transcriptional differences in head and muscle tissues, with few genes having matching expression patterns. Pathway components showing age-dependent expression differences were involved with stress response, metabolic, neural and chromatin remodeling functions. Middle-aged tissues also showed a significant increase in transcriptional drift-variance (TD), which in the CNS included multiple proteolytic pathway components. Overall, IF-treatment had a demonstrably positive impact on aged transcriptomes, partly ameliorating both fold and variance changes. Consistent with these findings, aged IF-treated flies displayed more youthful metabolic, behavioral and basal proteolytic profiles that closely correlated with transcriptional alterations to key components. These results indicate that even modest dietary changes can have therapeutic consequences, slowing the progressive decline of multiple cellular systems, including proteostasis in the aging nervous system. PMID:29642630
Zhang, Sharon; Ratliff, Eric P; Molina, Brandon; El-Mecharrafie, Nadja; Mastroianni, Jessica; Kotzebue, Roxanne W; Achal, Madhulika; Mauntz, Ruth E; Gonzalez, Arysa; Barekat, Ayeh; Bray, William A; Macias, Andrew M; Daugherty, Daniel; Harris, Greg L; Edwards, Robert A; Finley, Kim D
2018-04-10
The progressive decline of the nervous system, including protein aggregate formation, reflects the subtle dysregulation of multiple functional pathways. Our previous work has shown intermittent fasting (IF) enhances longevity, maintains adult behaviors and reduces aggregates, in part, by promoting autophagic function in the aging Drosophila brain. To clarify the impact that IF-treatment has upon aging, we used high throughput RNA-sequencing technology to examine the changing transcriptome in adult Drosophila tissues. Principle component analysis (PCA) and other analyses showed ~1200 age-related transcriptional differences in head and muscle tissues, with few genes having matching expression patterns. Pathway components showing age-dependent expression differences were involved with stress response, metabolic, neural and chromatin remodeling functions. Middle-aged tissues also showed a significant increase in transcriptional drift-variance (TD), which in the CNS included multiple proteolytic pathway components. Overall, IF-treatment had a demonstrably positive impact on aged transcriptomes, partly ameliorating both fold and variance changes. Consistent with these findings, aged IF-treated flies displayed more youthful metabolic, behavioral and basal proteolytic profiles that closely correlated with transcriptional alterations to key components. These results indicate that even modest dietary changes can have therapeutic consequences, slowing the progressive decline of multiple cellular systems, including proteostasis in the aging nervous system.
Numerical Modeling of Sub-Wavelength Anti-Reflective Structures for Solar Module Applications
Han, Katherine; Chang, Chih-Hung
2014-01-01
This paper reviews the current progress in mathematical modeling of anti-reflective subwavelength structures. Methods covered include effective medium theory (EMT), finite-difference time-domain (FDTD), transfer matrix method (TMM), the Fourier modal method (FMM)/rigorous coupled-wave analysis (RCWA) and the finite element method (FEM). Time-based solutions to Maxwell’s equations, such as FDTD, have the benefits of calculating reflectance for multiple wavelengths of light per simulation, but are computationally intensive. Space-discretized methods such as FDTD and FEM output field strength results over the whole geometry and are capable of modeling arbitrary shapes. Frequency-based solutions such as RCWA/FMM and FEM model one wavelength per simulation and are thus able to handle dispersion for regular geometries. Analytical approaches such as TMM are appropriate for very simple thin films. Initial disadvantages such as neglect of dispersion (FDTD), inaccuracy in TM polarization (RCWA), inability to model aperiodic gratings (RCWA), and inaccuracy with metallic materials (FDTD) have been overcome by most modern software. All rigorous numerical methods have accurately predicted the broadband reflection of ideal, graded-index anti-reflective subwavelength structures; ideal structures are tapered nanostructures with periods smaller than the wavelengths of light of interest and lengths that are at least a large portion of the wavelengths considered. PMID:28348287
A neuroimaging investigation of attribute framing and individual differences.
Murch, Kevin B; Krawczyk, Daniel C
2014-10-01
Functional magnetic resonance imaging was used to evaluate the neural basis of framing effects. We tested the reflexive and reflective systems model of social cognition as it relates to framing. We also examined the relationships among frame susceptibility, intelligence and personality measures. Participants evaluated whether personal attributes applied to themselves from multiple perspectives and in positive and negative frames. Participants rated whether each statement was descriptive or not and endorsed positive frames more than negative frames. Individual differences on frame decisions enabled us to form high and low frame susceptibility groups. Endorsement of frame-consistent attributes was associated with personality factors, cognitive reflection and intelligence. Reflexive brain regions were associated with positive frames while reflective areas were associated with negative frames. Region of Interest analyses showed that frame-inconsistent responses were associated with increased activation within reflective cognitive control regions including the left dorsolateral prefrontal cortex (PFC), dorsomedial PFC and left ventrolateral PFC. Frame-consistent responses were associated with increased activation in the right orbitofrontal cortex. These results demonstrate that individual differences in frame susceptibility influence personal attribute evaluations. Overall, this study clarifies the neural correlates of the reflective and reflexive systems of social cognition as applied to decisions about social attributions. © The Author (2013). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.
Theory of fiber-optic, evanescent-wave spectroscopy and sensors
NASA Astrophysics Data System (ADS)
Messica, A.; Greenstein, A.; Katzir, A.
1996-05-01
A general theory for fiber-optic, evanescent-wave spectroscopy and sensors is presented for straight, uncladded, step-index, multimode fibers. A three-dimensional model is formulated within the framework of geometric optics. The model includes various launching conditions, input and output end-face Fresnel transmission losses, multiple Fresnel reflections, bulk absorption, and evanescent-wave absorption. An evanescent-wave sensor response is analyzed as a function of externally controlled parameters such as coupling angle, f number, fiber length, and diameter. Conclusions are drawn for several experimental apparatuses.
Tarvin, Jeffrey A.
1987-01-01
An optical dielectric humidity sensor which includes a dielectric mirror having multiple alternating layers of two porous water-adsorbent dielectric materials with differing indices of refraction carried by a translucent substrate. A narrow-band polarized light source is positioned to direct light energy onto the mirror, and detectors are positioned to receive light energy transmitted through and reflected by the mirror. A ratiometer indicates humidity in the atmosphere which surrounds the dielectric mirror as a function of a ratio of light energies incident on the detectors.
Tarvin, J.A.
1987-02-10
An optical dielectric humidity sensor is disclosed which includes a dielectric mirror having multiple alternating layers of two porous water-adsorbent dielectric materials with differing indices of refraction carried by a translucent substrate. A narrow-band polarized light source is positioned to direct light energy onto the mirror, and detectors are positioned to receive light energy transmitted through and reflected by the mirror. A ratiometer indicates humidity in the atmosphere which surrounds the dielectric mirror as a function of a ratio of light energies incident on the detectors. 2 figs.
Using Reflectance Measurements to Determine Ecosystem Light Use Efficiency
NASA Astrophysics Data System (ADS)
Huemmrich, K. F.; Middleton, E. M.; Hall, F. G.; Knox, R. G.; Walter-Shea, E.; Verma, S. B.
2006-05-01
Understanding the dynamics of the global carbon cycle requires an accurate determination of the spatial and temporal distribution of photosynthetic CO2 uptake by terrestrial vegetation. Remote sensing observations may provide the spatially extensive observations required for this type of analysis. A light use efficiency model is one approach to modeling carbon fluxes driven by remotely sensed inputs. Photosynthetic down-regulation has been associated with changes in the apparent spectral reflectance of leaves and these responses may permit the estimation of ecosystem photosynthetic light use efficiency (LUE). At a prairie site in Oklahoma, CO2 flux measurements from an eddy covariance system along with biophysical data were collected through 1998 and 1999. During the growing seasons hyperspectral reflectance measurements were collected in nearby plots at multiple times in a day at approximately monthly intervals. LUE is calculated as the ratio of carbon uptake by the ecosystem and the fraction of photosynthetically active radiation (PAR) absorbed by green leaves. The LUE values are compared with reflectance indexes examining how relationships vary over hours, months, and years. For this system a number of different reflectance indexes have been found to correlate with LUE; including the Photochemical Reflectance Index (PRI) and the Structure Independent Pigment Index (SIPI); as well as spectral first derivatives at 460, 550, and 615nm; and second derivatives at 510 and 620nm. This methodology provides a nondestructive, repeatable, direct comparison between ecosystem carbon fluxes and spectral reflectance at scales relevant to remote sensing.
Reconstructing in-vivo reflectance spectrum of pigmented skin lesion by Monte Carlo simulation
NASA Astrophysics Data System (ADS)
Wang, Shuang; He, Qingli; Zhao, Jianhua; Lui, Harvey; Zeng, Haishan
2012-03-01
In dermatology applications, diffuse reflectance spectroscopy has been extensively investigated as a promising tool for the noninvasive method to distinguish melanoma from benign pigmented skin lesion (nevus), which is concentrated with the skin chromophores like melanin and hemoglobin. We carried out a theoretical study to examine melanin distribution in human skin tissue and establish a practical optical model for further pigmented skin investigation. The theoretical simulation was using junctional nevus as an example. A multiple layer skin optical model was developed on established anatomy structures of skin, the published optical parameters of different skin layers, blood and melanin. Monte Carlo simulation was used to model the interaction between excitation light and skin tissue and rebuild the diffuse reflectance process from skin tissue. A testified methodology was adopted to determine melanin contents in human skin based on in vivo diffuse reflectance spectra. The rebuild diffuse reflectance spectra were investigated by adding melanin into different layers of the theoretical model. One of in vivo reflectance spectra from Junctional nevi and their surrounding normal skin was studied by compare the ratio between nevus and normal skin tissue in both the experimental and simulated diffuse reflectance spectra. The simulation result showed a good agreement with our clinical measurements, which indicated that our research method, including the spectral ratio method, skin optical model and modifying the melanin content in the model, could be applied in further theoretical simulation of pigmented skin lesions.
NASA Astrophysics Data System (ADS)
Bai, Chao-Ying; Huang, Guo-Jiao; Li, Xiao-Ling; Zhou, Bing; Greenhalgh, Stewart
2013-11-01
To overcome the deficiency of some current grid-/cell-based ray tracing algorithms, which are only able to handle first arrivals or primary reflections (or conversions) in anisotropic media, we have extended the functionality of the multistage irregular shortest-path method to 2-D/3-D tilted transversely isotropic (TTI) media. The new approach is able to track multiple transmitted/reflected/converted arrivals composed of any kind of combinations of transmissions, reflections and mode conversions. The basic principle is that the seven parameters (five elastic parameters plus two polar angles defining the tilt of the symmetry axis) of the TTI media are sampled at primary nodes, and the group velocity values at secondary nodes are obtained by tri-linear interpolation of the primary nodes across each cell, from which the group velocities of the three wave modes (qP, qSV and qSH) are calculated. Finally, we conduct grid-/cell-based wave front expansion to trace multiple transmitted/reflected/converted arrivals from one region to the next. The results of calculations in uniform anisotropic media indicate that the numerical results agree with the analytical solutions except in directions of SV-wave triplications, at which only the lowest velocity value is selected at the singularity points by the multistage irregular shortest-path anisotropic ray tracing method. This verifies the accuracy of the methodology. Several simulation results show that the new method is able to efficiently and accurately approximate situations involving continuous velocity variations and undulating discontinuities, and that it is suitable for any combination of multiple transmitted/reflected/converted arrival tracking in TTI media of arbitrary strength and tilt. Crosshole synthetic traveltime tomographic tests have been performed, which highlight the importance of using such code when the medium is distinctly anisotropic.
Step Back and Consider: Learning from Reflective Practice in Infant Mental Health
ERIC Educational Resources Information Center
Gatti, Shelley Neilsen; Watson, Christopher L.; Siegel, Carol F.
2011-01-01
Reflective practice is used in different fields such as education and mental health. The educational form of reflective practice has been around since the 1930s (Dewey, as cited in Pedro, 2006); it is a problem-solving process that facilitates examination of behavior and responses to behavior. It takes into consideration multiple factors,…
ERIC Educational Resources Information Center
Carver, Cynthia L; Klein, C. Suzanne
2016-01-01
Drawing on data collected as part of a qualitative action research study, our analysis examines the reflective thinking skill of candidates as they begin a two-year principal preparation program. As leadership educators, we noticed that our highest performing students were also the most skilled at thinking reflectively. Using candidates' writing…
Multiple scattering in the remote sensing of natural surfaces
DOE Office of Scientific and Technical Information (OSTI.GOV)
Li, Wen-Hao; Weeks, R.; Gillespie, A.R.
1996-07-01
Radiosity models predict the amount of light scattered many times (multiple scattering) among scene elements in addition to light interacting with a surface only once (direct reflectance). Such models are little used in remote sensing studies because they require accurate digital terrain models and, typically, large amounts of computer time. We have developed a practical radiosity model that runs relatively quickly within suitable accuracy limits, and have used it to explore problems caused by multiple-scattering in image calibration, terrain correction, and surface roughness estimation for optical images. We applied the radiosity model to real topographic surfaces sampled at two verymore » different spatial scales: 30 m (rugged mountains) and 1 cm (cobbles and gravel on an alluvial fan). The magnitude of the multiple-scattering (MS) effect varies with solar illumination geometry, surface reflectivity, sky illumination and surface roughness. At the coarse scale, for typical illumination geometries, as much as 20% of the image can be significantly affected (>5%) by MS, which can account for as much as {approximately}10% of the radiance from sunlit slopes, and much more for shadowed slopes, otherwise illuminated only by skylight. At the fine scale, radiance from as much as 30-40% of the scene can have a significant MS component, and the MS contribution is locally as high as {approximately}70%, although integrating to the meter scale reduces this limit to {approximately}10%. Because the amount of MS increases with reflectivity as well as roughness, MS effects will distort the shape of reflectance spectra as well as changing their overall amplitude. The change is proportional to surface roughness. Our results have significant implications for determining reflectivity and surface roughness in remote sensing.« less
Method and Apparatus for Measuring Fluid Flow
NASA Technical Reports Server (NTRS)
Arndt, G. Dickey (Inventor); Nguyen, Than X. (Inventor); Carl, James R. (Inventor)
1995-01-01
The invention is a method and apparatus for monitoring the presence, concentration, and the movement of fluids. It is based on utilizing electromagnetic measurements of the complex permittivity of the fluids for detecting and monitoring the fluid. More particularly the apparatus uses one or more microwave probes which are placed at the locations where the measurements are to be made. A radio frequency signal is transmitted to the probe and the reflected signal is phase and amplitude detected at a rapid rate for the purpose of identifying the fluids, based on their dielectric constant at the probe. The apparatus can be used for multiple purposes including measures of flow rates, turbulence, dispersion, fluid identification, and changes in flow conditions of multiple fluids or multiple states of a single fluid in a flowline or a holding container. The apparatus includes a probe consisting of two electrical conductors separated by an insulator. A radio frequency signal is communicated to the probe and is reflected back from the portion of the probe exposed to the fluid. The radio frequency signal also provides a reference signal. An oscillator generates a second signal which combined with each of the reference signal and the reflected signal to produce signals of lower frequencies to facilitate filtering and amplifying those signals. The two signals are then mixed in a detector to produce an output signal that is representative of the phase and amplitude change caused by the reflection of the signal at the probe exposed to the fluid. The detector may be a dual phase detector that provides two such output signals that are in phase quadrature. A phase shifter may be provided for selectively changing the phase of the reference signal to improve the sensitivity of at least one of the output signals for more accurate readings and/or for calibration purposes. The two outputs that are in quadrature with respect to each other may be simultaneously monitored to account for drift errors. The output signals are digitized and provided to a computer at a sample rate which may be very high. The computer is operable to identify the fluid based on its complex permittivity as may be useful for identifying the flow rates, determining the fluid mixture ratio, detecting impurities in the fluid, and so forth. Novelty is believed to reside in the use of the real part of complex permittivity to measure small difference in permittivity of the fluid.
Applying Multiple Intelligences
ERIC Educational Resources Information Center
Christodoulou, Joanna A.
2009-01-01
The ideas of multiple intelligences introduced by Howard Gardner of Harvard University more than 25 years ago have taken form in many ways, both in schools and in other sometimes-surprising settings. The silver anniversary of Gardner's learning theory provides an opportunity to reflect on the ways multiple intelligences theory has taken form and…
Yu, Jingkai; Finley, Russell L
2009-01-01
High-throughput experimental and computational methods are generating a wealth of protein-protein interaction data for a variety of organisms. However, data produced by current state-of-the-art methods include many false positives, which can hinder the analyses needed to derive biological insights. One way to address this problem is to assign confidence scores that reflect the reliability and biological significance of each interaction. Most previously described scoring methods use a set of likely true positives to train a model to score all interactions in a dataset. A single positive training set, however, may be biased and not representative of true interaction space. We demonstrate a method to score protein interactions by utilizing multiple independent sets of training positives to reduce the potential bias inherent in using a single training set. We used a set of benchmark yeast protein interactions to show that our approach outperforms other scoring methods. Our approach can also score interactions across data types, which makes it more widely applicable than many previously proposed methods. We applied the method to protein interaction data from both Drosophila melanogaster and Homo sapiens. Independent evaluations show that the resulting confidence scores accurately reflect the biological significance of the interactions.
Zhu, Mengjian; Ben Shalom, Moshe; Mishchsenko, Artem; Fal'ko, Vladimir; Novoselov, Kostya; Geim, Andre
2018-02-08
Ballistic Josephson junctions are predicted to support a number of exotic physics processess, providing an ideal system to inject the supercurrent in the quantum Hall regime. Herein, we demonstrate electrical transport measurements on ballistic superconductor-graphene-superconductor junctions by contacting graphene to niobium with a junction length up to 1.5 μm. Hexagonal boron nitride encapsulation and one-dimensional edge contacts guarantee high-quality graphene Josephson junctions with a mean free path of several micrometers and record-low contact resistance. Transports in normal states including the observation of Fabry-Pérot oscillations and Sharvin resistance conclusively witness the ballistic propagation in the junctions. The critical current density J C is over one order of magnitude larger than that of the previously reported junctions. Away from the charge neutrality point, the I C R N product (I C is the critical current and R N the normal state resistance of junction) is nearly a constant, independent of carrier density n, which agrees well with the theory for ballistic Josephson junctions. Multiple Andreev reflections up to the third order are observed for the first time by measuring the differential resistance in the micrometer-long ballistic graphene Josephson junctions.
Analysis of multiple soybean phytonutrients by near-infrared reflectance spectroscopy.
Zhang, Gaoyang; Li, Penghui; Zhang, Wenfei; Zhao, Jian
2017-05-01
Improvement of the nutritional quality of soybean is usually facilitated by a vast range of soybean germplasm with enough information about their multiple phytonutrients. In order to acquire this essential information from a huge number of soybean samples, a rapid analytic method is urgently required. Here, a nondestructive near-infrared reflectance spectroscopy (NIRS) method was developed for rapid and accurate measurement of 25 nutritional components in soybean simultaneously, including fatty acids palmitic acid, stearic acid, oleic acid, linoleic acid, and linolenic acid, vitamin E (VE), α-VE, γ-VE, δ-VE, saponins, isoflavonoids, and flavonoids. Modified partial least squares regression and first, second, third, and fourth derivative transformation was applied for the model development. The 1 minus variance ratio (1-VR) value of the optimal model can reach between the highest 0.95 and lowest 0.64. The predicted values of phytonutrients in soybean using NIRS technology are comparable to those obtained from using the traditional spectrum or chemical methods. A robust NIRS can be adopted as a reliable method to evaluate complex plant constituents for screening large-scale samples of soybean germplasm resources or genetic populations for improvement of nutritional qualities. Graphical Abstract ᅟ.
Reconstructing surface wave profiles from reflected acoustic pulses using multiple receivers.
Walstead, Sean P; Deane, Grant B
2014-08-01
Surface wave shapes are determined by analyzing underwater reflected acoustic signals collected at multiple receivers. The transmitted signals are of nominal frequency 300 kHz and are reflected off surface gravity waves that are paddle-generated in a wave tank. An inverse processing algorithm reconstructs 50 surface wave shapes over a length span of 2.10 m. The inverse scheme uses a broadband forward scattering model based on Kirchhoff's diffraction formula to determine wave shapes. The surface reconstruction algorithm is self-starting in that source and receiver geometry and initial estimates of wave shape are determined from the same acoustic signals used in the inverse processing. A high speed camera provides ground-truth measurements of the surface wave field for comparison with the acoustically derived surface waves. Within Fresnel zone regions the statistical confidence of the inversely optimized surface profile exceeds that of the camera profile. Reconstructed surfaces are accurate to a resolution of about a quarter-wavelength of the acoustic pulse only within Fresnel zones associated with each source and receiver pair. Multiple isolated Fresnel zones from multiple receivers extend the spatial extent of accurate surface reconstruction while overlapping Fresnel zones increase confidence in the optimized profiles there.
NASA Astrophysics Data System (ADS)
Wang, Wei; Hu, Zhengliang; Ma, Mingxiang; Lin, Huizu; Hu, Yongming
2014-03-01
A fiber Bragg grating based (FBG-based) Fabry-Perot (FP) sensor system utilizing multiple reflections between two strong FBGs with different reflectiveties to enhance the sensitivity is proposed. The different interference signals are obtained by using different multiple-path-matched Michelson interferometers (MIs). The system is lighted by the ultra-narrow line width erbium-doped fiber ring laser and the signal is demodulated by phase-generated carrier (PGC) scheme. The method to choose the optimal parameters of the FBG-based asymmetric FP sensor and the different matching MIs is analyzed. The experimental results show that each matching MI can steadily enhance the sensitivity of the demodulated signal in the bandwidth of 80-8000 Hz. The sensitivity of the system can be enhanced about 19.1 dB when the light reflects nine times between the two FBGs. Further more, this system can be used to extend the dynamic range and the effective working bandwidth and so on.
Rogers, Geoffrey
2018-06-01
The Yule-Nielsen effect is an influence on halftone color caused by the diffusion of light within the paper upon which the halftone ink is printed. The diffusion can be characterized by a point spread function. In this paper, a point spread function for paper is derived using the multiple-path model of reflection. This model treats the interaction of light with turbid media as a random walk. Using the multiple-path point spread function, a general expression is derived for the average reflectance of light from a frequency-modulated halftone, in which dot size is constant and the number of dots is varied, with the arrangement of dots random. It is also shown that the line spread function derived from the multiple-path model has the form of a Lorentzian function.
Hower, J.C.; O'Keefe, J.M.K.; Watt, M.A.; Pratt, T.J.; Eble, C.F.; Stucker, J.D.; Richardson, A.R.; Kostova, I.J.
2009-01-01
Macrinite is a, generally, rare inertinite maceral, often incorporating remnants and fragments of other macerals, including vitrinite, liptinite, and other inertinite. The associated inertinites include multiple forms of funginite. Funginite is also commonly found in association with vitrinite of slightly elevated reflectance and with degraded varieties of vitrinite. Together with the highly degraded macrinite, the latter two associations are here inferred to be part of a continuum of fungal and microbial degradation of peat. In any case, the origin of some macrinite is potentially distinct from that of inertinite generated by fire. ?? 2009 Elsevier B.V. All rights reserved.
Liu, Chao; Gu, Jinwei
2014-01-01
Classifying raw, unpainted materials--metal, plastic, ceramic, fabric, and so on--is an important yet challenging task for computer vision. Previous works measure subsets of surface spectral reflectance as features for classification. However, acquiring the full spectral reflectance is time consuming and error-prone. In this paper, we propose to use coded illumination to directly measure discriminative features for material classification. Optimal illumination patterns--which we call "discriminative illumination"--are learned from training samples, after projecting to which the spectral reflectance of different materials are maximally separated. This projection is automatically realized by the integration of incident light for surface reflection. While a single discriminative illumination is capable of linear, two-class classification, we show that multiple discriminative illuminations can be used for nonlinear and multiclass classification. We also show theoretically that the proposed method has higher signal-to-noise ratio than previous methods due to light multiplexing. Finally, we construct an LED-based multispectral dome and use the discriminative illumination method for classifying a variety of raw materials, including metal (aluminum, alloy, steel, stainless steel, brass, and copper), plastic, ceramic, fabric, and wood. Experimental results demonstrate its effectiveness.
ERIC Educational Resources Information Center
Forzani, Elena; Leu, Donald J.
2017-01-01
In this joint reflection, the authors discuss the nature of literacy in relation to "New Literacies: A Dual-Level Theory of the Changing Nature of Literacy, Instruction, and Assessment" (Leu, Kinzer, Coiro, Castek, & Henry, 2013), a chapter reprinted in this issue of the "Journal of Education." They reflect on the meaning…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fernández-Perea, Mónica; Soufli, Regina; Robinson, Jeff C.
2012-01-01
We have developed new, corrosion-resistant Mg/SiC multilayer coatings which can be used to efficiently and simultaneously reflect extreme ultraviolet (EUV) radiation in single or multiple narrow bands centered at wavelengths in the spectral region from 25 to 80 nm. Corrosion mitigation is achieved through the use of partially amorphous Al-Mg thin layers. Three different multilayer design concepts were developed and deposited by magnetron sputtering and the reflectance was measured at near-normal incidence in a broad spectral range. Unprotected Mg/SiC multilayers were also deposited and measured for comparison. They were shown to efficiently reflect radiation at a wavelength of 76.9 nmmore » with a peak reflectance of 40.6% at near-normal incidence, the highest experimental reflectance reported at this wavelength for a narrowband coating. The demonstration of multilayer coatings with corrosion resistance and multiplewavelength EUV performance is of great interest in the development of mirrors for space-borne solar physics telescopes and other applications requiring long-lasting coatings with narrowband response in multiple emission lines across the EUV range.« less
Springfield, Emily; Gwozdek, Anne E; Peet, Melissa; Kerschbaum, Wendy E
2012-04-01
Program evaluation is a necessary component of curricular change and innovation. It ascertains whether an innovation has met benchmarks and contributes to the body of knowledge about educational methodologies and supports the use of evidence-based practice in teaching. Education researchers argue that rigorous program evaluation should utilize a mixed-method approach, triangulating both qualitative and quantitative methods to understand program effectiveness. This approach was used to evaluate the University of Michigan Dental Hygiene Degree Completion E-Learning (online) Program. Quantitative data included time spent on coursework, grades, publications, course evaluation results, and survey responses. Qualitative data included student and faculty responses in focus groups and on surveys as well as students' portfolio reflections. The results showed the program was academically rigorous, fostering students' ability to connect theory with practice and apply evidence-based practice principles. These results also demonstrated that the students had learned to critically reflect on their practice and develop expanded professional identities; going beyond the role of clinician, they began to see themselves as educators, advocates, and researchers. This evaluation model is easily adaptable and is applicable to any health science or other professional degree program. This study also raised important questions regarding the effect of meta-reflection on student confidence and professional behavior.
A Multi-organisational Approach to Service Delivery
NASA Astrophysics Data System (ADS)
Purchase, Valerie; Mills, John; Parry, Glenn
Who is involved in delivering a service? There has been growing recognition in a wide variety of contexts that service is increasingly being delivered by multi-rather than single-organisational entities. Such recognition is evident not only in our experience but in a number of areas of literature including strategy development, core competence analysis, operations and supply chain management, and is reflected in and further facilitated by ICT developments. Customers have always been involved in some degree in the process of value delivery and such involvement is increasing to include complex co-creation of value. Such interactions are challenging when they involve individual customers, however, this becomes ever more challenging when the 'customer' is another organisation or when there are multiple 'customers'. Within this chapter we will consider some of the key drivers for a multi-organisational approach to service delivery; examine the ways in which the parties involved in service co-creation have expanded to include multiple service providers and customers; and finally, identify some of the challenges created by a multi-organisational approach to service delivery.
Imaging outcome measures for progressive multiple sclerosis trials
Moccia, Marcello; de Stefano, Nicola; Barkhof, Frederik
2017-01-01
Imaging markers that are reliable, reproducible and sensitive to neurodegenerative changes in progressive multiple sclerosis (MS) can enhance the development of new medications with a neuroprotective mode-of-action. Accordingly, in recent years, a considerable number of imaging biomarkers have been included in phase 2 and 3 clinical trials in primary and secondary progressive MS. Brain lesion count and volume are markers of inflammation and demyelination and are important outcomes even in progressive MS trials. Brain and, more recently, spinal cord atrophy are gaining relevance, considering their strong association with disability accrual; ongoing improvements in analysis methods will enhance their applicability in clinical trials, especially for cord atrophy. Advanced magnetic resonance imaging (MRI) techniques (e.g. magnetization transfer ratio (MTR), diffusion tensor imaging (DTI), spectroscopy) have been included in few trials so far and hold promise for the future, as they can reflect specific pathological changes targeted by neuroprotective treatments. Position emission tomography (PET) and optical coherence tomography have yet to be included. Applications, limitations and future perspectives of these techniques in clinical trials in progressive MS are discussed, with emphasis on measurement sensitivity, reliability and sample size calculation. PMID:29041865
Havlicek, Judy
2014-01-01
Little is known about maltreatment among foster youth transitioning to adulthood. Multiple entries into out-of-home care and unsuccessful attempts at reunification may nevertheless reflect extended exposure to chronic maltreatment and multiple types of victimization. This study used administrative data from the Illinois Department of Children and Family Services to identify all unduplicated allegations of maltreatment in a cohort of 801 foster youth transitioning to adulthood in the state of Illinois. A latent variable modeling approach generated profiles of maltreatment based on substantiated and unsubstantiated reports of maltreatment taken from state administrative data. Four indicators of maltreatment were included in the latent class analysis: multiple types of maltreatment, predominant type of maltreatment, chronicity, and number of different perpetrators. The analysis identified four subpopulations of foster youth in relation to maltreatment. Study findings highlight the heterogeneity of maltreatment in the lives of foster youth transitioning to adulthood and draw attention to a need to raise awareness among service providers to screen for chronic maltreatment and multiple types of victimization. © The Author(s) 2014.
ERIC Educational Resources Information Center
Fagioli, Sabrina; Macaluso, Emiliano
2009-01-01
Behavioral studies indicate that subjects are able to divide attention between multiple streams of information at different locations. However, it is still unclear to what extent the observed costs reflect processes specifically associated with spatial attention, versus more general interference due the concurrent monitoring of multiple streams of…
USDA-ARS?s Scientific Manuscript database
The wide array of applications using quantum dots (QDs) for detection of multiple analytes reflects the versatility of the technology. In this study, a novel immunoassay using 2 types of sensors (QDs and an enzyme) were simultaneously used for detecting multiple structurally different low-molecular...
Drought monitoring using remote sensing of evapotranspiration
USDA-ARS?s Scientific Manuscript database
Drought assessment is a complex endeavor, requiring monitoring of deficiencies in multiple components of the hydrologic budget. Precipitation anomalies reflect variability in water supply to the land surface, while soil moisture (SM), ground and surface water anomalies reflect deficiencies in moist...
Tremor evidence for dynamically triggered creep events on the deep San Andreas Fault
NASA Astrophysics Data System (ADS)
Peng, Z.; Shelly, D. R.; Hill, D. P.; Aiken, C.
2010-12-01
Deep tectonic tremor has been observed along major subduction zones and the San Andreas fault (SAF) in central and southern California. It appears to reflect deep fault slip, and it is often seen to be triggered by small stresses, including passing seismic waves from large regional and teleseismic earthquakes. Here we examine tremor activity along the Parkfield-Cholame section of the SAF from mid-2001 to early 2010, scrutinizing its relationship with regional and teleseismic earthquakes. Based on similarities in the shape and timing of seismic waveforms, we conclude that triggered and ambient tremor share common sources and a common physical mechanism. Utilizing this similarity in waveforms, we detect tremor triggered by numerous large events, including previously unreported triggering from the recent 2009 Mw7.3 Honduras, 2009 Mw8.1 Samoa, and 2010 Mw8.8 Chile earthquakes at teleseismic distances, and the relatively small 2007 Mw5.4 Alum Rock and 2008 Mw5.4 Chino Hills earthquakes at regional distances. We also find multiple examples of systematic migration in triggered tremor, similar to ambient tremor migration episodes observed at other times. Because these episodes propagate much more slowly than the triggering waves, the migration likely reflects a small, triggered creep event. As with ambient tremor bursts, triggered tremor at times persists for multiple days, probably indicating a somewhat larger creep event. This activity provides a clear example of delayed dynamic triggering, with a mechanism perhaps also relevant for triggering of regular earthquakes.
Dendritic Spine Pathology in Schizophrenia
Glausier, Jill R.; Lewis, David A.
2012-01-01
Schizophrenia is a neurodevelopmental disorder whose clinical features include impairments in perception, cognition and motivation. These impairments reflect alterations in neuronal circuitry within and across multiple brain regions that are due, at least in part, to deficits in dendritic spines, the site of most excitatory synaptic connections. Dendritic spine alterations have been identified in multiple brain regions in schizophrenia, but are best characterized in layer 3 of the neocortex, where pyramidal cell spine density is lower. These spine deficits appear to arise during development, and thus are likely the result of disturbances in the molecular mechanisms that underlie spine formation, pruning, and/or maintenance. Each of these mechanisms may provide insight into novel therapeutic targets for preventing or repairing the alterations in neural circuitry that mediate the debilitating symptoms of schizophrenia. PMID:22546337
Hyperspectral Remote Sensing of Terrestrial Ecosystem Productivity from ISS
NASA Astrophysics Data System (ADS)
Huemmrich, K. F.; Campbell, P. K. E.; Gao, B. C.; Flanagan, L. B.; Goulden, M.
2017-12-01
Data from the Hyperspectral Imager for Coastal Ocean (HICO), mounted on the International Space Station (ISS), were used to develop and test algorithms for remotely retrieving ecosystem productivity. The ISS orbit introduces both limitations and opportunities for observing ecosystem dynamics. Twenty six HICO images were used from four study sites representing different vegetation types: grasslands, shrubland, and forest. Gross ecosystem production (GEP) data from eddy covariance were matched with HICO-derived spectra. Multiple algorithms were successful relating spectral reflectance with GEP, including: Spectral Vegetation Indices (SVI), SVI in a light use efficiency model framework, spectral shape characteristics through spectral derivatives and absorption feature analysis, and statistical models leading to Multiband Hyperspectral Indices (MHI) from stepwise regressions and Partial Least Squares Regression (PLSR). Algorithms were able to achieve r2 better than 0.7 for both GEP at the overpass time and daily GEP. These algorithms were successful using a diverse set of observations combining data from multiple years, multiple times during growing season, different times of day, with different view angles, and different vegetation types. The demonstrated robustness of the algorithms presented in this study over these conditions provides some confidence in mapping spatial patterns of GEP, describing variability within fields as well as the regional patterns based only on spectral reflectance information. The ISS orbit provides periods with multiple observations collected at different times of the day within a period of a few days. Diurnal GEP patterns were estimated comparing the half-hourly average GEP from the flux tower against HICO estimates of GEP (r2=0.87) if morning, midday, and afternoon observations were available for average fluxes in the time period.
Tanaka, N; Kunihiro, Y; Kubo, M; Kawano, R; Oishi, K; Ueda, K; Gondo, T
2018-05-29
To identify characteristic high-resolution computed tomography (CT) findings for individual collagen vascular disease (CVD)-related interstitial pneumonias (IPs). The HRCT findings of 187 patients with CVD, including 55 patients with rheumatoid arthritis (RA), 50 with systemic sclerosis (SSc), 46 with polymyositis/dermatomyositis (PM/DM), 15 with mixed connective tissue disease, 11 with primary Sjögren's syndrome, and 10 with systemic lupus erythematosus, were evaluated. Lung parenchymal abnormalities were compared among CVDs using χ 2 test, Kruskal-Wallis test, and multiple logistic regression analysis. A CT-pathology correlation was performed in 23 patients. In RA-IP, honeycombing was identified as the significant indicator based on multiple logistic regression analyses. Traction bronchiectasis (81.8%) was further identified as the most frequent finding based on χ 2 test. In SSc IP, lymph node enlargement and oesophageal dilatation were identified as the indicators based on multiple logistic regression analyses, and ground-glass opacity (GGO) was the most extensive based on Kruskal-Wallis test, which reflects the higher frequency of the pathological nonspecific interstitial pneumonia (NSIP) pattern present in the CT-pathology correlation. In PM/DM IP, airspace consolidation and the absence of honeycombing were identified as the indicators based on multiple logistic regression analyses, and predominance of consolidation over GGO (32.6%) and predominant subpleural distribution of GGO/consolidation (41.3%) were further identified as the most frequent findings based on χ 2 test, which reflects the higher frequency of the pathological NSIP and/or the organising pneumonia patterns present in the CT-pathology correlation. Several characteristic high-resolution CT findings with utility for estimating underlying CVD were identified. Copyright © 2018 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.
Zn1-xCdxSe/ZnSe multiple quantum well photomodulators
NASA Astrophysics Data System (ADS)
Tang, Jiuyao; Kawakami, Yoichi; Fujita, Shizuo; Fujita, Shigeo
1996-10-01
ZnCdSe/ZnSe multiple quantum well (MQW) transmission and reflection photomodulators operating at room temperature were fabricated employing quantum-confined Stark effect on the exciton absorption. Samples were grown on p-type GaAs substrates by MBE with an i-Zn0.87Cd0.13Se/ZnSe MQW heterostructure sandwiched by a ZnSe p-n junction. The transmission modulator was constructed with a Zn0.87Cd0.13Se/ZnSe MQW glued onto a piece of ITO film-covered glass with silver paste and epoxy. To avoid absorption in GaAs substrates, a window with a diameter of about 2 mm was opened using a selective etch. For the reflective use an Al mirror was deposited on the glass back surface, the device then operates in reflection with the light to be modulated making a double pass through the active quantum well region, thereby increasing the modulation amplitude. Measurement results are given in this paper for transmission, reflection, differential transmission, differential absorption, and differential reflection as a function of the incident photon wavelength and the applied field.
NASA Astrophysics Data System (ADS)
Adibelli-Sahin, Elif; Deniz, Hasan
2017-04-01
This qualitative study explored elementary teachers' perceptions about the effective features of explicit-reflective nature of science (NOS) instruction. Our participants were four elementary teachers from a public charter school located in the Southwestern U.S.A. The four elementary teachers participated in an academic year-long professional development about NOS which consisted of NOS training and NOS teaching phases. After each phase of the professional development, we specifically asked our participants which features of the explicit-reflective NOS instruction they found effective in improving their NOS conceptions by presenting pre- and post-profiles of their NOS conceptions. We identified nine features perceived by the participants as effective components of explicit-reflective NOS instruction: (1) specific focus on NOS content, (2) participation in hands-on NOS activities, (3) introductory NOS readings, (4) multiple types/forms of reflection, (5) multiple exposure to NOS content, (6) structural consistency in the presentation of NOS content, (7) the evaluation of secondary NOS data from elementary students, (8) the analysis of national and state science standards in terms of NOS content, and (9) NOS teaching experience.
Thoracic epidural analgesia in a child with multiple traumatic rib fractures.
Keech, Brian M
2015-12-01
The morbidity and mortality associated with blunt thoracic trauma are significant and can be multisystem in nature. Of these, pulmonary complications, including ventilatory impairment secondary to pain, have been recognized to be the most consequential. Although several analgesic strategies have emerged, thoracic epidural analgesia (TEA) has arguably demonstrated superior efficacy and is used frequently in adults. Unfortunately, TEA is rarely used in children after blunt thoracic trauma, but may be of considerable benefit. This low rate of use likely reflects one or more of several factors potentially encountered when considering the use of TEA in pediatric chest wall trauma. Among them are (1) uncertainty regarding safety and efficacy; (2) the technical challenges of pediatric thoracic epidural placement, including technique and equipment concerns; and (3) drug selection, dosing, and toxicity. The following case review describes the successful application of TEA in a 4-year-old boy after multiple traumatic rib fractures and associated pneumothorax and pulmonary contusion. Copyright © 2015 Elsevier Inc. All rights reserved.
User's manual for CNVUFAC, the general dynamics heat-transfer radiation view factor program
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wong, R. L.
CNVUFAC, the General Dynamics heat-transfer radiation veiw factor program, has been adapted for use on the LLL CDC 7600 computer system. The input and output have been modified, and a node incrementing logic was included to make the code compatible with the TRUMP thermal analyzer and related codes. The program performs the multiple integration necessary to evaluate the geometric black-body radiaton node to node view factors. Card image output that contains node number and view factor information is generated for input into the related program GRAY. Program GRAY is then used to include the effects of gray-body emissivities and multiplemore » reflections, generating the effective gray-body view factors usable in TRUMP. CNVUFAC uses an elemental area summation scheme to evaluate the multiple integrals. The program permits shadowing and self-shadowing. The basic configuration shapes that can be considered are cylinders, cones, spheres, ellipsoids, flat plates, disks, toroids, and polynomials of revolution. Portions of these shapes can also be considered.« less
Adaptive graph-based multiple testing procedures
Klinglmueller, Florian; Posch, Martin; Koenig, Franz
2016-01-01
Multiple testing procedures defined by directed, weighted graphs have recently been proposed as an intuitive visual tool for constructing multiple testing strategies that reflect the often complex contextual relations between hypotheses in clinical trials. Many well-known sequentially rejective tests, such as (parallel) gatekeeping tests or hierarchical testing procedures are special cases of the graph based tests. We generalize these graph-based multiple testing procedures to adaptive trial designs with an interim analysis. These designs permit mid-trial design modifications based on unblinded interim data as well as external information, while providing strong family wise error rate control. To maintain the familywise error rate, it is not required to prespecify the adaption rule in detail. Because the adaptive test does not require knowledge of the multivariate distribution of test statistics, it is applicable in a wide range of scenarios including trials with multiple treatment comparisons, endpoints or subgroups, or combinations thereof. Examples of adaptations are dropping of treatment arms, selection of subpopulations, and sample size reassessment. If, in the interim analysis, it is decided to continue the trial as planned, the adaptive test reduces to the originally planned multiple testing procedure. Only if adaptations are actually implemented, an adjusted test needs to be applied. The procedure is illustrated with a case study and its operating characteristics are investigated by simulations. PMID:25319733
Utilizing a Tower Based System for Optical Sensing of Ecosystem Carbon Fluxes
NASA Astrophysics Data System (ADS)
Huemmrich, K. F.; Corp, L. A.; Middleton, E.; Campbell, P. K. E.; Landis, D.; Kustas, W. P.
2015-12-01
Optical sampling of spectral reflectance and solar induced fluorescence provide information on the physiological status of vegetation that can be used to infer stress responses and estimates of production. Multiple repeated observations are required to observe the effects of changing environmental conditions on vegetation. This study examines the use of optical signals to determine inputs to a light use efficiency (LUE) model describing productivity of a cornfield where repeated observations of carbon flux, spectral reflectance and fluorescence were collected. Data were collected at the Optimizing Production Inputs for Economic and Environmental Enhancement (OPE3) fields (39.03°N, 76.85°W) at USDA Beltsville Agricultural Research Center. Agricultural Research Service researchers measured CO2 fluxes using eddy covariance methods throughout the growing season. Optical measurements were made from the nearby tower supporting the NASA FUSION sensors. The sensor system consists of two dual channel, upward and downward looking, spectrometers used to simultaneously collect high spectral resolution measurements of reflected and fluoresced light from vegetation canopies at multiple view angles. Estimates of chlorophyll fluorescence, combined with measures of vegetation pigment content and the Photosynthetic Reflectance Index (PRI) derived from the spectral reflectance are compared with CO2 fluxes over diurnal periods for multiple days. The relationships among the different optical measurements indicate that they are providing different types of information on the vegetation and that combinations of these measurements provide improved retrievals of CO2 fluxes than any index alone
EPA Workshop on Epigenetics and Cumulative Risk ...
Agenda Download the Workshop Agenda (PDF) The workshop included presentations and discussions by scientific experts pertaining to three topics (i.e., epigenetic changes associated with diverse stressors, key science considerations in understanding epigenetic changes, and practical application of epigenetic tools to address cumulative risks from environmental stressors), to address several questions under each topic, and included an opportunity for attendees to participate in break-out groups, provide comments and ask questions. Workshop Goals The workshop seeks to examine the opportunity for use of aggregate epigenetic change as an indicator in cumulative risk assessment for populations exposed to multiple stressors that affect epigenetic status. Epigenetic changes are specific molecular changes around DNA that alter expression of genes. Epigenetic changes include DNA methylation, formation of histone adducts, and changes in micro RNAs. Research today indicates that epigenetic changes are involved in many chronic diseases (cancer, cardiovascular disease, obesity, diabetes, mental health disorders, and asthma). Research has also linked a wide range of stressors including pollution and social factors with occurrence of epigenetic alterations. Epigenetic changes have the potential to reflect impacts of risk factors across multiple stages of life. Only recently receiving attention is the nexus between the factors of cumulative exposure to environmental
Morgenstern, Hai; Rafaely, Boaz
2018-02-01
Spatial analysis of room acoustics is an ongoing research topic. Microphone arrays have been employed for spatial analyses with an important objective being the estimation of the direction-of-arrival (DOA) of direct sound and early room reflections using room impulse responses (RIRs). An optimal method for DOA estimation is the multiple signal classification algorithm. When RIRs are considered, this method typically fails due to the correlation of room reflections, which leads to rank deficiency of the cross-spectrum matrix. Preprocessing methods for rank restoration, which may involve averaging over frequency, for example, have been proposed exclusively for spherical arrays. However, these methods fail in the case of reflections with equal time delays, which may arise in practice and could be of interest. In this paper, a method is proposed for systems that combine a spherical microphone array and a spherical loudspeaker array, referred to as multiple-input multiple-output systems. This method, referred to as modal smoothing, exploits the additional spatial diversity for rank restoration and succeeds where previous methods fail, as demonstrated in a simulation study. Finally, combining modal smoothing with a preprocessing method is proposed in order to increase the number of DOAs that can be estimated using low-order spherical loudspeaker arrays.
Creating a Space for Acknowledgment and Generativity in Reflective Group Supervision.
Paré, David
2016-06-01
Small group supervision is a powerful venue for generative conversations because of the multiplicity of perspectives available and the potential for an appreciative audience to a practitioner's work. At the same time, the well-intentioned reflections by a few practitioners in a room can inadvertently duplicate normative discourses that circulate in the wider culture and the profession. This article explores the use of narrative practices for benefiting from the advantages of group supervision while mindful of the vulnerability that comes with sharing one's work among colleagues. The reflective group supervision processes described were modified from the work of Tom Andersen and Michael White to provide a venue that encourages the creative multiplicity of group conversation while discouraging unhelpful discourses which constrain generative conversation. © 2016 Family Process Institute.
Antoine, D; Morel, A
1998-04-20
Single and multiple scattering by molecules or by atmospheric aerosols only (homogeneous scattering), and heterogeneous scattering by aerosols and molecules, are recorded in Monte Carlo simulations. It is shown that heterogeneous scattering (1) always contributes significantly to the path reflectance (rho(path)), (2) is realized at the expense of homogeneous scattering, (3) decreases when aerosols are absorbing, and (4) introduces deviations in the spectral dependencies of reflectances compared with the Rayleigh exponent and the aerosol angstrom exponent. The ratio of rho(path) to the Rayleigh reflectance for an aerosol-free atmosphere is linearly related to the aerosol optical thickness. This result provides a basis for a new scheme for atmospheric correction of remotely sensed ocean color observations.
NASA Astrophysics Data System (ADS)
Usenik, Peter; Bürmen, Miran; Fidler, Aleš; Pernuš, Franjo; Likar, Boštjan
2012-03-01
Despite major improvements in dental healthcare and technology, dental caries remains one of the most prevalent chronic diseases of modern society. The initial stages of dental caries are characterized by demineralization of enamel crystals, commonly known as white spots, which are difficult to diagnose. Near-infrared (NIR) hyperspectral imaging is a new promising technique for early detection of demineralization which can classify healthy and pathological dental tissues. However, due to non-ideal illumination of the tooth surface the hyperspectral images can exhibit specular reflections, in particular around the edges and the ridges of the teeth. These reflections significantly affect the performance of automated classification and visualization methods. Cross polarized imaging setup can effectively remove the specular reflections, however is due to the complexity and other imaging setup limitations not always possible. In this paper, we propose an alternative approach based on modeling the specular reflections of hard dental tissues, which significantly improves the classification accuracy in the presence of specular reflections. The method was evaluated on five extracted human teeth with corresponding gold standard for 6 different healthy and pathological hard dental tissues including enamel, dentin, calculus, dentin caries, enamel caries and demineralized regions. Principal component analysis (PCA) was used for multivariate local modeling of healthy and pathological dental tissues. The classification was performed by employing multiple discriminant analysis. Based on the obtained results we believe the proposed method can be considered as an effective alternative to the complex cross polarized imaging setups.
A fast high-precision six-degree-of-freedom relative position sensor
NASA Astrophysics Data System (ADS)
Hughes, Gary B.; Macasaet, Van P.; Griswold, Janelle; Sison, Claudia A.; Lubin, Philip; Meinhold, Peter; Suen, Jonathan; Brashears, Travis; Zhang, Qicheng; Madajian, Jonathan
2016-03-01
Lasers are commonly used in high-precision measurement and profiling systems. Some laser measurement systems are based on interferometry principles, and others are based on active triangulation, depending on requirements of the application. This paper describes an active triangulation laser measurement system for a specific application wherein the relative position of two fixed, rigid mechanical components is to be measured dynamically with high precision in six degrees of freedom (DOF). Potential applications include optical systems with feedback to control for mechanical vibration, such as target acquisition devices with multiple focal planes. The method uses an array of several laser emitters mounted on one component. The lasers are directed at a reflective surface on the second component. The reflective surface consists of a piecewise-planar pattern such as a pyramid, or more generally a curved reflective surface such as a hyperbolic paraboloid. The reflected spots are sensed at 2-dimensional photodiode arrays on the emitter component. Changes in the relative position of the emitter component and reflective surface will shift the location of the reflected spots within photodiode arrays. Relative motion in any degree of freedom produces independent shifts in the reflected spot locations, allowing full six-DOF relative position determination between the two component positions. Response time of the sensor is limited by the read-out rate of the photodiode arrays. Algorithms are given for position determination with limits on uncertainty and sensitivity, based on laser and spot-sensor characteristics, and assuming regular surfaces. Additional uncertainty analysis is achievable for surface irregularities based on calibration data.
Interactions of multi-scale heterogeneity in the lithosphere: Australia
NASA Astrophysics Data System (ADS)
Kennett, B. L. N.; Yoshizawa, K.; Furumura, T.
2017-10-01
Understanding the complex heterogeneity of the continental lithosphere involves a wide variety of spatial scales and the synthesis of multiple classes of information. Seismic surface waves and multiply reflected body waves provide the main constraints on broad-scale structure, and bounds on the extent of the lithosphere-asthenosphere transition (LAT) can be found from the vertical gradients of S wavespeed. Information on finer-scale structures comes through body wave studies, including detailed seismic tomography and P-wave reflectivity extracted from stacked autocorrelograms of continuous component records. With the inclusion of deterministic large-scale structure and realistic medium-scale stochastic features fine-scale variations are subdued. The resulting multi-scale heterogeneity model for the Australian region gives a good representation of the character of observed seismograms and their geographic variations and matches the observations of P-wave reflectivity. P reflections in the 0.5-3.0 Hz band in the uppermost mantle suggest variations on vertical scales of a few hundred metres with amplitudes of the order of 1%. Interference of waves reflected or converted at sequences of such modest variations in physical properties produce relatively simple behaviour for lower frequencies, which can suggest simpler structures than are actually present. Vertical changes in the character of fine-scale heterogeneity can produce apparent discontinuities. In Central Australia a 'mid-lithospheric discontinuity' can be tracked via changes in frequency content of station reflectivity, with links to the broad-scale pattern of wavespeed gradients and, in particular, the gradients of radial anisotropy. Comparisons with xenolith results from southeastern Australia indicate a strong tie between geochemical stratification and P-wave reflectivity.
Applying systems theory to the evaluation of a whole school approach to violence prevention.
Kearney, Sarah; Leung, Loksee; Joyce, Andrew; Ollis, Debbie; Green, Celia
2016-02-01
Issue addressed Our Watch led a complex 12-month evaluation of a whole school approach to Respectful Relationships Education (RRE) implemented in 19 schools. RRE is an emerging field aimed at preventing gender-based violence. This paper will illustrate how from an implementation science perspective, the evaluation was a critical element in the change process at both a school and policy level. Methods Using several conceptual approaches from systems science, the evaluation sought to examine how the multiple systems layers - student, teacher, school, community and government - interacted and influenced each other. A distinguishing feature of the evaluation included 'feedback loops'; that is, evaluation data was provided to participants as it became available. Evaluation tools included a combination of standardised surveys (with pre- and post-intervention data provided to schools via individualised reports), reflection tools, regular reflection interviews and summative focus groups. Results Data was shared during implementation with project staff, department staff and schools to support continuous improvement at these multiple systems levels. In complex settings, implementation can vary according to context; and the impact of evaluation processes, tools and findings differed across the schools. Interviews and focus groups conducted at the end of the project illustrated which of these methods were instrumental in motivating change and engaging stakeholders at both a school and departmental level and why. Conclusion The evaluation methods were a critical component of the pilot's approach, helping to shape implementation through data feedback loops and reflective practice for ongoing, responsive and continuous improvement. Future health promotion research on complex interventions needs to examine how the evaluation itself is influencing implementation. So what? The pilot has demonstrated that the evaluation, including feedback loops to inform project activity, were an asset to implementation. This has implications for other health promotion activities, where evaluation tools could be utilised to enhance, rather than simply measure, an intervention. The findings are relevant to a range of health promotion research activities because they demonstrate the importance of meta-evaluation techniques that seek to understand how the evaluation itself was influencing implementation and outcomes.
Hsu, Fong-Fu
2016-01-01
Ceramide is a huge lipid family consisting of diversified structures including various modifications in the fatty acyl chain and the long chain base (LCB). In this contribution, negative-ion ESI linear ion-trap multiple-stage mass spectrometric method (LIT MSn) towards complete structural determination of ceramides in ten major families characterized as the [M – H]− ions is described. Multiple sets of fragment ions reflecting the fatty acyl chain and LCB were observed in the CID MS2 spectrum, while the sequential MS3 and MS4 spectra contain structural information for locating the double bond and the functional groups, permitting realization of the fragmentation processes. Thereby, differentiation of ceramide molecules varied by chain length, the LCB (sphingosine, phytosphigosine, 6-hydroxy-sphingosine), and by the modification (α-hydroxy-, β-hydroxy-, ω-hydroxy-FA) can be achieved; and many isomeric structures in the biological specimen can be revealed in detail. PMID:27523779
Plasmacytomagenesis in Eμ-v-abl transgenic mice is accelerated when apoptosis is restrained
Vandenberg, Cassandra J.; Waring, Paul; Strasser, Andreas
2014-01-01
Mice susceptible to plasma cell tumors provide a useful model for human multiple myeloma. We previously showed that mice expressing an Eµ-v-abl oncogene solely develop plasmacytomas. Here we show that loss of the proapoptotic BH3-only protein Bim or, to a lesser extent, overexpression of antiapoptotic Bcl-2 or Mcl-1, significantly accelerated the development of plasmacytomas and increased their incidence. Disease was preceded by an increased abundance of plasma cells, presumably reflecting their enhanced survival capacity in vivo. Plasmacytomas of each genotype expressed high levels of v-abl and frequently harbored a rearranged c-myc gene, probably as a result of chromosome translocation. As in human multiple myelomas, elevated expression of cyclin D genes was common, and p53 deregulation was rare. Our results for plasmacytomas highlight the significance of antiapoptotic changes in multiple myeloma, which include elevated expression of Mcl-1 and, less frequently, Bcl-2, and suggest that closer attention to defects in Bim expression is warranted. PMID:24986687
Application of ground-penetrating-radar methods in hydrogeologic studies
Beres, Milan; Haeni, F.P.
1991-01-01
A ground-penetrating-radar system was used to study selected stratified-drift deposits in Connecticut. Ground-penetrating radar is a surface-geophysical method that depends on the emission, transmission, reflection, and reception of an electromagnetic pulse and can produce continuous high-resolution profiles of the subsurface rapidly and efficiently. Traverse locations on land included a well field in the town of Mansfield, a sand and gravel pit and a farm overlying a potential aquifer in the town of Coventry, and Haddam Meadows State Park in the town of Haddam. Traverse locations on water included the Willimantic River in Coventry and Mansfield Hollow Lake in Mansfield. The penetration depth of the radar signal ranged from about 20 feet in fine-grained glaciolacustrine sediments to about 70 feet in coarse sand and gravel. Some land records in coarse-grained sediments show a distinct, continuous reflection from the water table about 5 to 11 feet below land surface. Parallel reflectors on the records are interpreted as fine-grained sediments. Hummocky or chaotic reflectors are interpreted as cross-bedded or coarse-grained sediments. Other features observed on some of the radar records include the till and bedrock surface. Records collected on water had distinct water-bottom multiples (more than one reflection) and diffraction patterns from boulders. The interpretation of the radar records, which required little or no processing, was verified by using lithologic logs from test holes located along some of the land traverses and near the water traverses.
Crotta, Matteo; Rizzi, Rita; Varisco, Giorgio; Daminelli, Paolo; Cunico, Elena Cosciani; Luini, Mario; Graber, Hans Ulrich; Paterlini, Franco; Guitian, Javier
2016-03-01
Quantitative microbial risk assessment (QMRA) models are extensively applied to inform management of a broad range of food safety risks. Inevitably, QMRA modeling involves an element of simplification of the biological process of interest. Two features that are frequently simplified or disregarded are the pathogenicity of multiple strains of a single pathogen and consumer behavior at the household level. In this study, we developed a QMRA model with a multiple-strain approach and a consumer phase module (CPM) based on uncertainty distributions fitted from field data. We modeled exposure to staphylococcal enterotoxin A in raw milk in Lombardy; a specific enterotoxin production module was thus included. The model is adaptable and could be used to assess the risk related to other pathogens in raw milk as well as other staphylococcal enterotoxins. The multiplestrain approach, implemented as a multinomial process, allowed the inclusion of variability and uncertainty with regard to pathogenicity at the bacterial level. Data from 301 questionnaires submitted to raw milk consumers were used to obtain uncertainty distributions for the CPM. The distributions were modeled to be easily updatable with further data or evidence. The sources of uncertainty due to the multiple-strain approach and the CPM were identified, and their impact on the output was assessed by comparing specific scenarios to the baseline. When the distributions reflecting the uncertainty in consumer behavior were fixed to the 95th percentile, the risk of exposure increased up to 160 times. This reflects the importance of taking into consideration the diversity of consumers' habits at the household level and the impact that the lack of knowledge about variables in the CPM can have on the final QMRA estimates. The multiple-strain approach lends itself to use in other food matrices besides raw milk and allows the model to better capture the complexity of the real world and to be capable of geographical specificity.
Granberg, Sarah; Dahlström, Jennie; Möller, Claes; Kähäri, Kim; Danermark, Berth
2014-02-01
To review the literature in order to identify outcome measures used in research on adults with hearing loss (HL) as part of the ICF Core Sets development project, and to describe study and population characteristics of the reviewed studies. A systematic review methodology was applied using multiple databases. A comprehensive search was conducted and two search pools were created, pool I and pool II. The study population included adults (≥ 18 years of age) with HL and oral language as the primary mode of communication. 122 studies were included. Outcome measures were distinguished by 'instrument type', and 10 types were identified. In total, 246 (pool I) and 122 (pool II) different measures were identified, and only approximately 20% were extracted twice or more. Most measures were related to speech recognition. Fifty-one different questionnaires were identified. Many studies used small sample sizes, and the sex of participants was not revealed in several studies. The low prevalence of identified measures reflects a lack of consensus regarding the optimal outcome measures to use in audiology. Reflections and discussions are made in relation to small sample sizes and the lack of sex differentiation/descriptions within the included articles.
Pulse homodyne field disturbance sensor
McEwan, Thomas E.
1997-01-01
A field disturbance sensor operates with relatively low power, provides an adjustable operating range, is not hypersensitive at close range, allows co-location of multiple sensors, and is inexpensive to manufacture. The sensor includes a transmitter that transmits a sequence of transmitted bursts of electromagnetic energy. The transmitter frequency is modulated at an intermediate frequency. The sequence of bursts has a burst repetition rate, and each burst has a burst width and comprises a number of cycles at a transmitter frequency. The sensor includes a receiver which receives electromagnetic energy at the transmitter frequency, and includes a mixer which mixes a transmitted burst with reflections of the same transmitted burst to produce an intermediate frequency signal. Circuitry, responsive to the intermediate frequency signal indicates disturbances in the sensor field. Because the mixer mixes the transmitted burst with reflections of the transmitted burst, the burst width defines the sensor range. The burst repetition rate is randomly or pseudo-randomly modulated so that bursts in the sequence of bursts have a phase which varies. A second range-defining mode transmits two radio frequency bursts, where the time spacing between the bursts defines the maximum range divided by two.
Pulse homodyne field disturbance sensor
McEwan, T.E.
1997-10-28
A field disturbance sensor operates with relatively low power, provides an adjustable operating range, is not hypersensitive at close range, allows co-location of multiple sensors, and is inexpensive to manufacture. The sensor includes a transmitter that transmits a sequence of transmitted bursts of electromagnetic energy. The transmitter frequency is modulated at an intermediate frequency. The sequence of bursts has a burst repetition rate, and each burst has a burst width and comprises a number of cycles at a transmitter frequency. The sensor includes a receiver which receives electromagnetic energy at the transmitter frequency, and includes a mixer which mixes a transmitted burst with reflections of the same transmitted burst to produce an intermediate frequency signal. Circuitry, responsive to the intermediate frequency signal indicates disturbances in the sensor field. Because the mixer mixes the transmitted burst with reflections of the transmitted burst, the burst width defines the sensor range. The burst repetition rate is randomly or pseudo-randomly modulated so that bursts in the sequence of bursts have a phase which varies. A second range-defining mode transmits two radio frequency bursts, where the time spacing between the bursts defines the maximum range divided by two. 12 figs.
ERIC Educational Resources Information Center
Ozgen, Kemal; Tataroglu, Berna; Alkan, Huseyin
2011-01-01
The present study aims to identify pre-service mathematics teachers' multiple intelligence domains and learning style profiles, and to establish relationships between them. Employing the survey model, the study was conducted with the participation of 243 pre-service mathematics teachers. The study used the "multiple intelligence domains…
ERIC Educational Resources Information Center
Block, Stephanie D.; Foster, E. Michael; Pierce, Matthew W.; Berkoff, Molly C.; Runyan, Desmond K.
2013-01-01
In suspected child sexual abuse some professionals recommend multiple child interviews to increase the likelihood of disclosure or more details to improve decision-making and increase convictions. We modeled the yield of a policy of routinely conducting multiple child interviews and increased convictions. Our decision tree reflected the path of a…
NASA Astrophysics Data System (ADS)
Yoshida, Kenichiro; Nishidate, Izumi; Ojima, Nobutoshi; Iwata, Kayoko
2014-01-01
To quantitatively evaluate skin chromophores over a wide region of curved skin surface, we propose an approach that suppresses the effect of the shading-derived error in the reflectance on the estimation of chromophore concentrations, without sacrificing the accuracy of that estimation. In our method, we use multiple regression analysis, assuming the absorbance spectrum as the response variable and the extinction coefficients of melanin, oxygenated hemoglobin, and deoxygenated hemoglobin as the predictor variables. The concentrations of melanin and total hemoglobin are determined from the multiple regression coefficients using compensation formulae (CF) based on the diffuse reflectance spectra derived from a Monte Carlo simulation. To suppress the shading-derived error, we investigated three different combinations of multiple regression coefficients for the CF. In vivo measurements with the forearm skin demonstrated that the proposed approach can reduce the estimation errors that are due to shading-derived errors in the reflectance. With the best combination of multiple regression coefficients, we estimated that the ratio of the error to the chromophore concentrations is about 10%. The proposed method does not require any measurements or assumptions about the shape of the subjects; this is an advantage over other studies related to the reduction of shading-derived errors.
de Boer, Annette S.; Kremer, Kristin; Borgdorff, Martien W.; de Haas, Petra E. W.; Heersma, Herre F.; van Soolingen, Dick
2000-01-01
Mycobacterium tuberculosis isolates with identical IS6110 restriction fragment length polymorphism (RFLP) patterns are considered to originate from the same ancestral strain and thus to reflect ongoing transmission. In this study, we investigated 1,277 IS6110 RFLP patterns for the presence of multiple low-intensity bands (LIBs), which may indicate infections with multiple M. tuberculosis strains. We did not find any multiple LIBs, suggesting that multiple infections are rare in the Netherlands. However, we did observe a few LIBs in 94 patterns (7.4%) and examined the nature of this phenomenon. With single-colony cultures it was found that LIBs mostly represent mixed bacterial populations with slightly different RFLP patterns. Mixtures were expressed in RFLP patterns as LIBs when 10 to 30% of the DNA analyzed originated from a bacterial population with another RFLP pattern. Presumably, a part of the LIBs did not represent mixed bacterial populations, as in some clusters all strains exhibited LIBs in their RFLP patterns. The occurrence of LIBs was associated with increased age in patients. This may reflect either a gradual change of the bacterial population in the human body over time or IS6110-mediated genetic adaptation of M. tuberculosis to changes in the environmental conditions during the dormant state or reactivation thereafter. PMID:11101583
DETECTING OCEANS ON EXTRASOLAR PLANETS USING THE GLINT EFFECT
DOE Office of Scientific and Technical Information (OSTI.GOV)
Robinson, Tyler D.; Meadows, Victoria S.; Crisp, David, E-mail: robinson@astro.washington.ed
2010-09-20
Glint, the specular reflection of sunlight off Earth's oceans, may reveal the presence of oceans on an extrasolar planet. As an Earth-like planet nears crescent phases, the size of the ocean glint spot increases relative to the fraction of the illuminated disk, while the reflectivity of this spot increases. Both effects change the planet's visible reflectivity as a function of phase. However, strong forward scattering of radiation by clouds can also produce increases in a planet's reflectivity as it approaches crescent phases, and surface glint can be obscured by Rayleigh scattering and atmospheric absorption. Here, we explore the detectability ofmore » glint in the presence of an atmosphere and realistic phase-dependent scattering from oceans and clouds. We use the NASA Astrobiology Institute's Virtual Planetary Laboratory three-dimensional line-by-line, multiple-scattering spectral Earth model to simulate Earth's broadband visible brightness and reflectivity over an orbit. Our validated simulations successfully reproduce phase-dependent Earthshine observations. We find that the glinting Earth can be as much as 100% brighter at crescent phases than simulations that do not include glint, and that the effect is dependent on both orbital inclination and wavelength, where the latter dependence is caused by Rayleigh scattering limiting sensitivity to the surface. We show that this phenomenon may be observable using the James Webb Space Telescope paired with an external occulter.« less
Detecting Oceans on Extrasolar Planets Using the Glint Effect
NASA Astrophysics Data System (ADS)
Robinson, Tyler D.; Meadows, Victoria S.; Crisp, David
2010-09-01
Glint, the specular reflection of sunlight off Earth's oceans, may reveal the presence of oceans on an extrasolar planet. As an Earth-like planet nears crescent phases, the size of the ocean glint spot increases relative to the fraction of the illuminated disk, while the reflectivity of this spot increases. Both effects change the planet's visible reflectivity as a function of phase. However, strong forward scattering of radiation by clouds can also produce increases in a planet's reflectivity as it approaches crescent phases, and surface glint can be obscured by Rayleigh scattering and atmospheric absorption. Here, we explore the detectability of glint in the presence of an atmosphere and realistic phase-dependent scattering from oceans and clouds. We use the NASA Astrobiology Institute's Virtual Planetary Laboratory three-dimensional line-by-line, multiple-scattering spectral Earth model to simulate Earth's broadband visible brightness and reflectivity over an orbit. Our validated simulations successfully reproduce phase-dependent Earthshine observations. We find that the glinting Earth can be as much as 100% brighter at crescent phases than simulations that do not include glint, and that the effect is dependent on both orbital inclination and wavelength, where the latter dependence is caused by Rayleigh scattering limiting sensitivity to the surface. We show that this phenomenon may be observable using the James Webb Space Telescope paired with an external occulter.
Using Journals to Enhance Learning in Business Classes
ERIC Educational Resources Information Center
Hocking, Deborah E.
2010-01-01
This study investigates the process of using journals that incorporated holistic approaches (cognitive, affective, spiritual, multiple intelligences, and inclusive education) to infuse passion, engage students in deeper reflection, and foster higher level personal skills reflected in the American Institute of Certified Public Accountants' (AICPA)…
NASA Astrophysics Data System (ADS)
Starshynov, I.; Paniagua-Diaz, A. M.; Fayard, N.; Goetschy, A.; Pierrat, R.; Carminati, R.; Bertolotti, J.
2018-04-01
The propagation of monochromatic light through a scattering medium produces speckle patterns in reflection and transmission, and the apparent randomness of these patterns prevents direct imaging through thick turbid media. Yet, since elastic multiple scattering is fundamentally a linear and deterministic process, information is not lost but distributed among many degrees of freedom that can be resolved and manipulated. Here, we demonstrate experimentally that the reflected and transmitted speckle patterns are robustly correlated, and we unravel all the complex and unexpected features of this fundamentally non-Gaussian and long-range correlation. In particular, we show that it is preserved even for opaque media with thickness much larger than the scattering mean free path, proving that information survives the multiple scattering process and can be recovered. The existence of correlations between the two sides of a scattering medium opens up new possibilities for the control of transmitted light without any feedback from the target side, but using only information gathered from the reflected speckle.
Metasurface for multi-channel terahertz beam splitters and polarization rotators
NASA Astrophysics Data System (ADS)
Zang, XiaoFei; Gong, HanHong; Li, Zhen; Xie, JingYa; Cheng, QingQing; Chen, Lin; Shkurinov, Alexander P.; Zhu, YiMing; Zhuang, SongLin
2018-04-01
Terahertz beam splitters and polarization rotators are two typical devices with wide applications ranging from terahertz communication to system integration. However, they are faced with severe challenges in manipulating THz waves in multiple channels, which is desirable for system integration and device miniaturization. Here, we propose a method to design ultra-thin multi-channel THz beam splitters and polarization rotators simultaneously. The reflected beams are divided into four beams with nearly the same density under illumination of linear-polarized THz waves, while the polarization of reflected beams in each channel is modulated with a rotation angle or invariable with respect to the incident THz waves, leading to the multi-channel polarization rotator (multiple polarization rotation in the reflective channels) and beam splitter, respectively. Reflective metasurfaces, created by patterning metal-rods with different orientations on a polyimide film, were fabricated and measured to demonstrate these characteristics. The proposed approach provides an efficient way of controlling polarization of THz waves in various channels, which significantly simplifies THz functional devices and the experimental system.
NASA Technical Reports Server (NTRS)
Moore, Jason P. (Inventor)
2009-01-01
A system and method for determining a reflection wavelength of multiple Bragg gratings in a sensing optical fiber comprise: (1) a source laser; (2) an optical detector configured to detect a reflected signal from the sensing optical fiber; (3) a plurality of frequency generators configured to generate a signal having a frequency corresponding to an interferometer frequency of a different one of the plurality of Bragg gratings; (4) a plurality of demodulation elements, each demodulation element configured to combine the signal produced by a different one of the plurality of frequency generators with the detected signal from the sensing optical fiber; (5) a plurality of peak detectors, each peak detector configured to detect a peak of the combined signal from a different one of the demodulation elements; and (6) a laser wavenumber detection element configured to determine a wavenumber of the laser when any of the peak detectors detects a peak.
The "Face" of Diabetes: Insight Into Youths' Experiences as Expressed Through Drawing.
Elertson, Kathleen M; Liesch, Shari K; Babler, Elizabeth K
2016-06-01
The purpose of this descriptive pilot study was to assess the ability of youth to create a meaningful drawing related to living with type 1 diabetes and explore the benefits of expressing emotion through drawing in future interventional work. Youth aged 4 to 19 years (N = 242) with type I diabetes attending routine follow-up appointments within a pediatric specialty clinic were asked to draw: "If diabetes had a face what would it look like?" Drawings reflected many emotions and ranged from simple to complex in detail. Drawings reflected multiple experiences of living with diabetes including emotions, tools used for management, and effects of self-care. Youth were able to create drawings reflecting their experience of living with diabetes. Youth conveyed a variety of emotions, attitudes, and experiences in drawing the "face" of diabetes. Drawing during clinic visits provides opportunity to explore the unspoken experiences of living with a chronic health condition, which may not be obtained during routine clinical information gathering. Deeper understanding of patient's lived experience may assist providers in therapeutic management.
Liesch, Shari K; Babler, Elizabeth K
2016-01-01
Objective: The purpose of this descriptive pilot study was to assess the ability of youth to create a meaningful drawing related to living with type 1 diabetes and explore the benefits of expressing emotion through drawing in future interventional work. Methods: Youth aged 4 to 19 years (N = 242) with type I diabetes attending routine follow-up appointments within a pediatric specialty clinic were asked to draw: “If diabetes had a face what would it look like?” Results: Drawings reflected many emotions and ranged from simple to complex in detail. Drawings reflected multiple experiences of living with diabetes including emotions, tools used for management, and effects of self-care. Conclusions: Youth were able to create drawings reflecting their experience of living with diabetes. Youth conveyed a variety of emotions, attitudes, and experiences in drawing the “face” of diabetes. Drawing during clinic visits provides opportunity to explore the unspoken experiences of living with a chronic health condition, which may not be obtained during routine clinical information gathering. Deeper understanding of patient’s lived experience may assist providers in therapeutic management. PMID:28725833
Achana, Felix A; Cooper, Nicola J; Bujkiewicz, Sylwia; Hubbard, Stephanie J; Kendrick, Denise; Jones, David R; Sutton, Alex J
2014-07-21
Network meta-analysis (NMA) enables simultaneous comparison of multiple treatments while preserving randomisation. When summarising evidence to inform an economic evaluation, it is important that the analysis accurately reflects the dependency structure within the data, as correlations between outcomes may have implication for estimating the net benefit associated with treatment. A multivariate NMA offers a framework for evaluating multiple treatments across multiple outcome measures while accounting for the correlation structure between outcomes. The standard NMA model is extended to multiple outcome settings in two stages. In the first stage, information is borrowed across outcomes as well across studies through modelling the within-study and between-study correlation structure. In the second stage, we make use of the additional assumption that intervention effects are exchangeable between outcomes to predict effect estimates for all outcomes, including effect estimates on outcomes where evidence is either sparse or the treatment had not been considered by any one of the studies included in the analysis. We apply the methods to binary outcome data from a systematic review evaluating the effectiveness of nine home safety interventions on uptake of three poisoning prevention practices (safe storage of medicines, safe storage of other household products, and possession of poison centre control telephone number) in households with children. Analyses are conducted in WinBUGS using Markov Chain Monte Carlo (MCMC) simulations. Univariate and the first stage multivariate models produced broadly similar point estimates of intervention effects but the uncertainty around the multivariate estimates varied depending on the prior distribution specified for the between-study covariance structure. The second stage multivariate analyses produced more precise effect estimates while enabling intervention effects to be predicted for all outcomes, including intervention effects on outcomes not directly considered by the studies included in the analysis. Accounting for the dependency between outcomes in a multivariate meta-analysis may or may not improve the precision of effect estimates from a network meta-analysis compared to analysing each outcome separately.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tonkyn, Russell G.; Danby, Tyler O.; Birnbaum, Jerome C.
The complex optical refractive index contains the optical constants, n(more » $$\\tilde{u}$$)and k($$\\tilde{u}$$), which correspond to the dispersion and absorption of light within a medium, respectively. By obtaining the optical constants one can in principle model most optical phenomena in media and at interfaces including reflection, refraction and dispersion. We have developed improved protocols based on the use of multiple path lengths to determine the optical constants for dozens of liquids, including organic and organophosphorous compounds. Detailed description of the protocols to determine the infrared indices will be presented, along with preliminary results using the constants with their applications to optical modeling.« less
Effect of surface deposits on electromagnetic waves propagating in uniform ducts
NASA Technical Reports Server (NTRS)
Baumeister, Kenneth J.
1990-01-01
A finite-element Galerkin formulation was used to study the effect of material surface deposits on the reflective characteristics of straight uniform ducts with PEC (perfectly electric conducting) walls. Over a wide frequency range, the effect of both single and multiple surface deposits on the duct reflection coefficient were examined. The power reflection coefficient was found to be significantly increased by the addition of deposits on the wall.
Farah, Nicolas; Francis, Ziad; Abboud, Marie
2014-09-01
We explore in our study the effects of electrons and X-rays irradiations on the newest version of the Gafchromic EBT3 film. Experiments are performed using the Varian "TrueBeam 1.6" medical accelerator delivering 6 MV X-ray photons and 6 MeV electron beams as desired. The main interest is to compare the responses of EBT3 films exposed to two separate beams of electrons and photons, for radiation doses ranging up to 500 cGy. The analysis is done on a flatbed EPSON 10000 XL scanner and cross checked on a HP Scanjet 4850 scanner. Both scanners are used in reflection mode taking into account landscape and portrait scanning positions. After thorough verifications, the reflective scanning method can be used on EBT3 as an economic alternative to the transmission method which was also one of the goals of this study. A comparison is also done between single scan configuration including all samples in a single A4 (HP) or A3 (EPSON) format area and multiple scan procedure where each sample is scanned separately on its own. The images analyses are done using the ImageJ software. Results show significant influence of the scanning configuration but no significant differences between electron and photon irradiations for both single and multiple scan configurations. In conclusion, the film provides a reliable relative dose measurement method for electrons and photons irradiations in the medical field applications. Copyright © 2014 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.
Chen, Yu-Wen; Chen, Chien-Chih; Huang, Po-Jung; Tseng, Sheng-Hao
2016-01-01
Diffuse reflectance spectroscopy (DRS) based on the frequency-domain (FD) technique has been employed to investigate the optical properties of deep tissues such as breast and brain using source to detector separation up to 40 mm. Due to the modeling and system limitations, efficient and precise determination of turbid sample optical properties from the FD diffuse reflectance acquired at a source-detector separation (SDS) of around 1 mm has not been demonstrated. In this study, we revealed that at SDS of 1 mm, acquiring FD diffuse reflectance at multiple frequencies is necessary for alleviating the influence of inevitable measurement uncertainty on the optical property recovery accuracy. Furthermore, we developed artificial neural networks (ANNs) trained by Monte Carlo simulation generated databases that were capable of efficiently determining FD reflectance at multiple frequencies. The ANNs could work in conjunction with a least-square optimization algorithm to rapidly (within 1 second), accurately (within 10%) quantify the sample optical properties from FD reflectance measured at SDS of 1 mm. In addition, we demonstrated that incorporating the steady-state apparatus into the FD DRS system with 1 mm SDS would enable obtaining broadband absorption and reduced scattering spectra of turbid samples in the wavelength range from 650 to 1000 nm. PMID:27446671
Bowleg, Lisa
2012-07-01
Intersectionality is a theoretical framework that posits that multiple social categories (e.g., race, ethnicity, gender, sexual orientation, socioeconomic status) intersect at the micro level of individual experience to reflect multiple interlocking systems of privilege and oppression at the macro, social-structural level (e.g., racism, sexism, heterosexism). Public health's commitment to social justice makes it a natural fit with intersectionality's focus on multiple historically oppressed populations. Yet despite a plethora of research focused on these populations, public health studies that reflect intersectionality in their theoretical frameworks, designs, analyses, or interpretations are rare. Accordingly, I describe the history and central tenets of intersectionality, address some theoretical and methodological challenges, and highlight the benefits of intersectionality for public health theory, research, and policy.
2012-01-01
Intersectionality is a theoretical framework that posits that multiple social categories (e.g., race, ethnicity, gender, sexual orientation, socioeconomic status) intersect at the micro level of individual experience to reflect multiple interlocking systems of privilege and oppression at the macro, social-structural level (e.g., racism, sexism, heterosexism). Public health’s commitment to social justice makes it a natural fit with intersectionality’s focus on multiple historically oppressed populations. Yet despite a plethora of research focused on these populations, public health studies that reflect intersectionality in their theoretical frameworks, designs, analyses, or interpretations are rare. Accordingly, I describe the history and central tenets of intersectionality, address some theoretical and methodological challenges, and highlight the benefits of intersectionality for public health theory, research, and policy. PMID:22594719
An Exploration of Group and Member Development in Experiential Groups
ERIC Educational Resources Information Center
Ohrt, Jonathan H.; Prochenko, Yulia; Stulmaker, Hayley; Huffman, David; Fernando, Delini; Swan, Karrie
2014-01-01
In this phenomenological study, we explored 52 group members' development in experiential groups. Specifically, participants completed 10 weekly journal reflections about their experiences as members and also reflected on the group's overall development. Four overall themes--exploration, transition, working, closure--as well as multiple subthemes…
Sopori, Bhushan; Rupnowski, Przemyslaw; Ulsh, Michael
2016-01-12
A monitoring system 100 comprising a material transport system 104 providing for the transportation of a substantially planar material 102, 107 through the monitoring zone 103 of the monitoring system 100. The system 100 also includes a line camera 106 positioned to obtain multiple line images across a width of the material 102, 107 as it is transported through the monitoring zone 103. The system 100 further includes an illumination source 108 providing for the illumination of the material 102, 107 transported through the monitoring zone 103 such that light reflected in a direction normal to the substantially planar surface of the material 102, 107 is detected by the line camera 106. A data processing system 110 is also provided in digital communication with the line camera 106. The data processing system 110 is configured to receive data output from the line camera 106 and further configured to calculate and provide substantially contemporaneous information relating to a quality parameter of the material 102, 107. Also disclosed are methods of monitoring a quality parameter of a material.
Zhao, Yi; Cao, Xiangyu; Gao, Jun; Liu, Xiao; Li, Sijia
2016-05-16
We demonstrate a simple reconfigurable metasurface with multiple functions. Anisotropic tiles are investigated and manufactured as fundamental elements. Then, the tiles are combined in a certain sequence to construct a metasurface. Each of the tiles can be adjusted independently which is like a jigsaw puzzle and the whole metasurface can achieve diverse functions by different layouts. For demonstration purposes, we realize polarization conversion, anomalous reflection and diffusion by a jigsaw puzzle metasurface with 6 × 6 pieces of anisotropic tile. Simulated and measured results prove that our method offers a simple and effective strategy for metasurface design.
Clinical Pharmacokinetics and Pharmacodynamics of Safinamide.
Müller, Thomas; Foley, Paul
2017-03-01
The symptoms of Parkinson's disease (PD) reflect disruptions of a number of brain neurotransmitter systems of varying type and degree. Pharmacological agents with multiple neurochemical mechanisms of action are therefore promising candidates for countering these problems and providing comprehensive symptomatic relief for patients. The pharmacological profile of safinamide includes reversible monoamine oxidase B inhibition, blockage of voltage-dependent Na + channels, modulation of Ca 2+ channels, and inhibition of glutamate release. Safinamide is administered once daily at oral doses of 50-100 mg; it is well-tolerated and safe. Clinical trials have found that it ameliorates motor symptoms when added to established levodopa or single dopamine receptor agonist therapy. The future role of safinamide in PD may be that it enables a reduction in the dosage of dopamine replacement therapies, thereby reducing the adverse effects associated with these treatments. The clinical convenience (once-daily administration), safety, and tolerability of safinamide are better than those of dopamine receptor agonists. The introduction of safinamide reflects a change of approach to drug development for anti-parkinsonian agents in that its broad spectrum of action corresponds to the multiple heterogeneous alterations of brain neurochemistry in PD, rather than being targeted at a single receptor type or neurochemical process. Safinamide is a promising new instrument for the effective symptomatic therapy of PD.
Mandelblat-Cerf, Yael; Ramesh, Rohan N; Burgess, Christian R; Patella, Paola; Yang, Zongfang; Lowell, Bradford B; Andermann, Mark L
2015-01-01
Agouti-related-peptide (AgRP) neurons—interoceptive neurons in the arcuate nucleus of the hypothalamus (ARC)—are both necessary and sufficient for driving feeding behavior. To better understand the functional roles of AgRP neurons, we performed optetrode electrophysiological recordings from AgRP neurons in awake, behaving AgRP-IRES-Cre mice. In free-feeding mice, we observed a fivefold increase in AgRP neuron firing with mounting caloric deficit in afternoon vs morning recordings. In food-restricted mice, as food became available, AgRP neuron firing dropped, yet remained elevated as compared to firing in sated mice. The rapid drop in spiking activity of AgRP neurons at meal onset may reflect a termination of the drive to find food, while residual, persistent spiking may reflect a sustained drive to consume food. Moreover, nearby neurons inhibited by AgRP neuron photostimulation, likely including satiety-promoting pro-opiomelanocortin (POMC) neurons, demonstrated opposite changes in spiking. Finally, firing of ARC neurons was also rapidly modulated within seconds of individual licks for liquid food. These findings suggest novel roles for antagonistic AgRP and POMC neurons in the regulation of feeding behaviors across multiple timescales. DOI: http://dx.doi.org/10.7554/eLife.07122.001 PMID:26159614
Yousefzadeh, Behrooz; Hodgson, Murray
2012-09-01
A beam-tracing model was used to study the acoustical responses of three empty, rectangular rooms with different boundary conditions. The model is wave-based (accounting for sound phase) and can be applied to rooms with extended-reaction surfaces that are made of multiple layers of solid, fluid, or poroelastic materials-the acoustical properties of these surfaces are calculated using Biot theory. Three room-acoustical parameters were studied in various room configurations: sound strength, reverberation time, and RApid Speech Transmission Index. The main objective was to investigate the effects of modeling surfaces as either local or extended reaction on predicted values of these three parameters. Moreover, the significance of modeling interference effects was investigated, including the study of sound phase-change on surface reflection. Modeling surfaces as of local or extended reaction was found to be significant for surfaces consisting of multiple layers, specifically when one of the layers is air. For multilayers of solid materials with an air-cavity, this was most significant around their mass-air-mass resonance frequencies. Accounting for interference effects made significant changes in the predicted values of all parameters. Modeling phase change on reflection, on the other hand, was found to be relatively much less significant.
Uses of vitrinite reflectance in determining thermal history in sedimentary basins
DOE Office of Scientific and Technical Information (OSTI.GOV)
Castano, J.R.
1985-02-01
Vitrinite reflectance (VR), adapted from coal petrology, came into routine use in the petroleum industry in the late 1960s. Initially, the principal goal was to help establish the VR limits for oil and gas generation. Subsequently, VR has become accepted as the most useful measure of burial history and paleotemperature, largely because VR affords the most practical means of measuring the progression of organic metamorphism. VR is used to correlate other measures of thermal history such as chemical maturity parameters, Rock-Eval t/sub max/, and burial-history reconstruction. VR can aid in identifying unconformities, geopressured sections, and thermally altered zones. Combined withmore » good temperature data, the determination of VR equivalents from temperature and burial time are used to evaluate the relationship of depth to log VR obtained directly. The time and temperature required for maturation in Tertiary basins stresses the interplay of both factors in the maturation process. Reflectance has been employed in deciphering the burial history and tectonic evolution of many areas, including structurally complex regions as the Alps and the Wyoming Overthrust Belt. Interpretational problems that arise include: (1) VR can be altered by the absorption of hydrogen-rich materials, oxidation, and natural coking; (2) the presence of reworked and caved organic matter produces multiple reflectance populations; and (3) vitrinite is sometimes difficult to distinguish from solid hydrocarbons and some inerts if the particle size is small. Most of these problems are resolved at the microscope. Interpretation is improved significantly by analyzing a series of samples rather than an isolated sample.« less
The Multiple Realities of Curriculum Policy Making.
ERIC Educational Resources Information Center
Hopmann, Stefan
Concerning curriculum making, it is impossible to integrate the different meanings of "curriculum" into a single formula. Read as social constructions, different conceptions reflect varying educational, social-political, and historical contexts. This paper explores how these contexts, or multiple realities, evolved historically and how…
Predictive Biomarkers for Asthma Therapy.
Medrek, Sarah K; Parulekar, Amit D; Hanania, Nicola A
2017-09-19
Asthma is a heterogeneous disease characterized by multiple phenotypes. Treatment of patients with severe disease can be challenging. Predictive biomarkers are measurable characteristics that reflect the underlying pathophysiology of asthma and can identify patients that are likely to respond to a given therapy. This review discusses current knowledge regarding predictive biomarkers in asthma. Recent trials evaluating biologic therapies targeting IgE, IL-5, IL-13, and IL-4 have utilized predictive biomarkers to identify patients who might benefit from treatment. Other work has suggested that using composite biomarkers may offer enhanced predictive capabilities in tailoring asthma therapy. Multiple biomarkers including sputum eosinophil count, blood eosinophil count, fractional concentration of nitric oxide in exhaled breath (FeNO), and serum periostin have been used to identify which patients will respond to targeted asthma medications. Further work is needed to integrate predictive biomarkers into clinical practice.
Integration of multiple theories for the simulation of laser interference lithography processes
NASA Astrophysics Data System (ADS)
Lin, Te-Hsun; Yang, Yin-Kuang; Fu, Chien-Chung
2017-11-01
The periodic structure of laser interference lithography (LIL) fabrication is superior to other lithography technologies. In contrast to traditional lithography, LIL has the advantages of being a simple optical system with no mask requirements, low cost, high depth of focus, and large patterning area in a single exposure. Generally, a simulation pattern for the periodic structure is obtained through optical interference prior to its fabrication through LIL. However, the LIL process is complex and combines the fields of optical and polymer materials; thus, a single simulation theory cannot reflect the real situation. Therefore, this research integrates multiple theories, including those of optical interference, standing waves, and photoresist characteristics, to create a mathematical model for the LIL process. The mathematical model can accurately estimate the exposure time and reduce the LIL process duration through trial and error.
Method and Apparatus for Measuring Fluid Flow
NASA Technical Reports Server (NTRS)
Arndt, G. Dickey (Inventor); Nguyen, Thanh X. (Inventor); Carl, James R. (Inventor)
1997-01-01
Method and apparatus for making measurements on fluids related to their complex permeability are disclosed. A microwave probe is provided for exposure to the fluids. The probe can be non-intrusive or can also be positioned at the location where measurements are to be made. The impedance of the probe is determined. in part. by the complex dielectric constant of the fluids at the probe. A radio frequency signal is transmitted to the probe and the reflected signal is phase and amplitude detected at a rapid rate for the purpose of identifying the fluids. Multiple probes may be selectively positioned to monitor the behavior of the fluids including their flow rate. Fluids may be identified as between two or more different fluids as well as multiple phases of the same fluid based on differences between their complex permittivities.
The Olympics and harm reduction?
2012-01-01
The current anti-doping policy (‘war on doping’) resembles the ‘war on drugs’ in several aspects, including a zero-tolerance approach, ideology encroaching on human rights and public health principles, high cost using public money for repression and control, and attempts to shape internationally harmonized legal frameworks to attain its aim. Furthermore, even if for different reasons, both wars seem not to be able to attain their objectives, and possibly lead to more harm to society than they can prevent. The Olympic buzz is mounting and we can expect multiple headlines in the media on doping and anti-doping stories related to this event. In this article we describe current anti-doping policy, reflect on its multiple unplanned consequences, and end with a discussion, if lessons learned from harm reduction experiences in the illicit drugs field could be applied to anti-doping. PMID:22788912
Are Binary Separations related to their System Mass?
NASA Astrophysics Data System (ADS)
Sterzik, M. F.; Durisen, R. H.
2004-08-01
We compile most recent multiplicity fractions and binary separation distributions for different primary masses, including very low-mass and brown dwarf primaries, and compare them with dynamical decay models of small-N clusters. The model predictions are based on detailed numerical calculations of the internal cluster dynamics, as well as on Monte-Carlo methods. Both observations and models reflect the same trends: (1) The multiplicity fraction is an increasing function of the primary mass. (2) The mean binary separations are increasing with the system mass in the sense that very low-mass binaries have average separations around ≈ 4AU, while the binary separation distribution for solar-type primaries peaks at ≈ 40AU. M-type binary systems apparently preferentially populate intermediate separations. Similar specific energy at the time of cluster formation for all cluster masses can possibly explain this trend.
Integration of multiple theories for the simulation of laser interference lithography processes.
Lin, Te-Hsun; Yang, Yin-Kuang; Fu, Chien-Chung
2017-11-24
The periodic structure of laser interference lithography (LIL) fabrication is superior to other lithography technologies. In contrast to traditional lithography, LIL has the advantages of being a simple optical system with no mask requirements, low cost, high depth of focus, and large patterning area in a single exposure. Generally, a simulation pattern for the periodic structure is obtained through optical interference prior to its fabrication through LIL. However, the LIL process is complex and combines the fields of optical and polymer materials; thus, a single simulation theory cannot reflect the real situation. Therefore, this research integrates multiple theories, including those of optical interference, standing waves, and photoresist characteristics, to create a mathematical model for the LIL process. The mathematical model can accurately estimate the exposure time and reduce the LIL process duration through trial and error.
Benzalkonium Chloride and Glaucoma
Kaufman, Paul L.; Kiland, Julie A.
2014-01-01
Abstract Glaucoma patients routinely take multiple medications, with multiple daily doses, for years or even decades. Benzalkonium chloride (BAK) is the most common preservative in glaucoma medications. BAK has been detected in the trabecular meshwork (TM), corneal endothelium, lens, and retina after topical drop installation and may accumulate in those tissues. There is evidence that BAK causes corneal and conjunctival toxicity, including cell loss, disruption of tight junctions, apoptosis and preapoptosis, cytoskeleton changes, and immunoinflammatory reactions. These same effects have been reported in cultured human TM cells exposed to concentrations of BAK found in common glaucoma drugs and in the TM of primary open-angle glaucoma donor eyes. It is possible that a relationship exists between chronic exposure to BAK and glaucoma. The hypothesis that BAK causes/worsens glaucoma is being tested experimentally in an animal model that closely reflects human physiology. PMID:24205938
Obtaining reliable phase-gradient delays from otoacoustic emission data.
Shera, Christopher A; Bergevin, Christopher
2012-08-01
Reflection-source otoacoustic emission phase-gradient delays are widely used to obtain noninvasive estimates of cochlear function and properties, such as the sharpness of mechanical tuning and its variation along the length of the cochlear partition. Although different data-processing strategies are known to yield different delay estimates and trends, their relative reliability has not been established. This paper uses in silico experiments to evaluate six methods for extracting delay trends from reflection-source otoacoustic emissions (OAEs). The six methods include both previously published procedures (e.g., phase smoothing, energy-weighting, data exclusion based on signal-to-noise ratio) and novel strategies (e.g., peak-picking, all-pass factorization). Although some of the methods perform well (e.g., peak-picking), others introduce substantial bias (e.g., phase smoothing) and are not recommended. In addition, since standing waves caused by multiple internal reflection can complicate the interpretation and compromise the application of OAE delays, this paper develops and evaluates two promising signal-processing strategies, the first based on time-frequency filtering using the continuous wavelet transform and the second on cepstral analysis, for separating the direct emission from its subsequent reflections. Altogether, the results help to resolve previous disagreements about the frequency dependence of human OAE delays and the sharpness of cochlear tuning while providing useful analysis methods for future studies.
Qualitative Analysis of Written Reflections during a Teaching Certificate Program
Castleberry, Ashley N.; Payakachat, Nalin; Ashby, Sarah; Nolen, Amanda; Carle, Martha; Neill, Kathryn K.
2016-01-01
Objective. To evaluate the success of a teaching certificate program by qualitatively evaluating the content and extent of participants’ reflections. Methods. Two investigators independently identified themes within midpoint and final reflection essays across six program years. Each essay was evaluated to determine the extent of reflection in prompted teaching-related topic areas (strengths, weaknesses, assessment, feedback). Results. Twenty-eight themes were identified within 132 essays. Common themes encompassed content delivery, student assessment, personal successes, and challenges encountered. Deep reflection was exhibited, with 48% of essays achieving the highest level of critical reflection. Extent of reflection trended higher from midpoint to final essays, with significant increases in the strengths and feedback areas. Conclusion. The teaching certificate program fostered critical reflection and self-reported positive behavior change in teaching, thus providing a high-quality professional development opportunity. Such programs should strongly consider emphasizing critical reflection through required reflective exercises at multiple points within program curricula. PMID:26941436
NASA Astrophysics Data System (ADS)
Mariano, Adrian V.; Grossmann, John M.
2010-11-01
Reflectance-domain methods convert hyperspectral data from radiance to reflectance using an atmospheric compensation model. Material detection and identification are performed by comparing the compensated data to target reflectance spectra. We introduce two radiance-domain approaches, Single atmosphere Adaptive Cosine Estimator (SACE) and Multiple atmosphere ACE (MACE) in which the target reflectance spectra are instead converted into sensor-reaching radiance using physics-based models. For SACE, known illumination and atmospheric conditions are incorporated in a single atmospheric model. For MACE the conditions are unknown so the algorithm uses many atmospheric models to cover the range of environmental variability, and it approximates the result using a subspace model. This approach is sometimes called the invariant method, and requires the choice of a subspace dimension for the model. We compare these two radiance-domain approaches to a Reflectance-domain ACE (RACE) approach on a HYDICE image featuring concealed materials. All three algorithms use the ACE detector, and all three techniques are able to detect most of the hidden materials in the imagery. For MACE we observe a strong dependence on the choice of the material subspace dimension. Increasing this value can lead to a decline in performance.
NASA Technical Reports Server (NTRS)
Benford, Steve; Bowers, John; Fahlen, Lennart E.; Greenhalgh, Chris; Snowdon, Dave
1994-01-01
This paper explores the issue of user embodiment within collaborative virtual environments. By user embodiment we mean the provision of users with appropriate body images so as to represent them to others and also to themselves. By collaborative virtual environments we mean multi-user virtual reality systems which support cooperative work (although we argue that the results of our exploration may also be applied to other kinds of collaborative systems). The main part of the paper identifies a list of embodiment design issues including: presence, location, identity, activity, availability, history of activity, viewpoint, action point, gesture, facial expression, voluntary versus involuntary expression, degree of presence, reflecting capabilities, manipulating the user's view of others, representation across multiple media, autonomous and distributed body parts, truthfulness and efficiency. Following this, we show how these issues are reflected in our own DIVE and MASSIVE prototype collaborative virtual environments.
Nurses’ Experiences of Managing and Management in a Critical Care Unit
Ogle, K. Robyn; Glass, Nel
2014-01-01
In this article, we describe the major findings of an ethnographic study undertaken to investigate nurses’ experiences of managing nurses and being managed by nurses in an Australian critical care unit. Our purpose was to valorize and make space for nurses to speak of their experiences and investigate the cultural practices and knowledges that comprised nursing management discourses. Subjugated practices, knowledges, and discourses were identified, revealing how nurses were inscribed by, or resisted, the discourses, including their multiple mobile subject positions. Informed by critical, feminist, and postmodern perspectives, nine mobile subject positions were identified. Direct participant observation, participant interviews, and reflective field notes were analyzed for dominant and subjugated discourses. The major finding described is the subject position of “junior novice.” Nurses informed by dominant patriarchal and organizational discourses participated in constructing and reinscribing their own submissive identity reflected in interprofessional relations that lacked individual valuing and undermined their self-esteem. PMID:28462287
Control system health test system and method
Hoff, Brian D.; Johnson, Kris W.; Akasam, Sivaprasad; Baker, Thomas M.
2006-08-15
A method is provided for testing multiple elements of a work machine, including a control system, a component, a sub-component that is influenced by operations of the component, and a sensor that monitors a characteristic of the sub-component. In one embodiment, the method is performed by the control system and includes sending a command to the component to adjust a first parameter associated with an operation of the component. Also, the method includes detecting a sensor signal from the sensor reflecting a second parameter associated with a characteristic of the sub-component and determining whether the second parameter is acceptable based on the command. The control system may diagnose at least one of the elements of the work machine when the second parameter of the sub-component is not acceptable.
Reynolds, Jacob D; Case, Laure K; Krementsov, Dimitry N; Raza, Abbas; Bartiss, Rose; Teuscher, Cory
2017-06-01
Month-season of birth (M-SOB) is a risk factor in multiple chronic diseases, including multiple sclerosis (MS), where the lowest and greatest risk of developing MS coincide with the lowest and highest birth rates, respectively. To determine whether M-SOB effects in such chronic diseases as MS can be experimentally modeled, we examined the effect of M-SOB on susceptibility of C57BL/6J mice to experimental autoimmune encephalomyelitis (EAE). As in MS, mice that were born during the M-SOB with the lowest birth rate were less susceptible to EAE than mice born during the M-SOB with the highest birth rate. We also show that the M-SOB effect on EAE susceptibility is associated with differential production of multiple cytokines/chemokines by neuroantigen-specific T cells that are known to play a role in EAE pathogenesis. Taken together, these results support the existence of an M-SOB effect that may reflect seasonally dependent developmental differences in adaptive immune responses to self-antigens independent of external stimuli, including exposure to sunlight and vitamin D. Moreover, our documentation of an M-SOB effect on EAE susceptibility in mice allows for modeling and detailed analysis of mechanisms that underlie the M-SOB effect in not only MS but in numerous other diseases in which M-SOB impacts susceptibility.-Reynolds, J. D., Case, L. K., Krementsov, D. N., Raza, A., Bartiss, R., Teuscher, C. Modeling month-season of birth as a risk factor in mouse models of chronic disease: from multiple sclerosis to autoimmune encephalomyelitis. © FASEB.
NASA Astrophysics Data System (ADS)
Duadi, Hamootal; Fixler, Dror
2015-05-01
Light reflectance and transmission from soft tissue has been utilized in noninvasive clinical measurement devices such as the photoplethysmograph (PPG) and reflectance pulse oximeter. Incident light on the skin travels into the underlying layers and is in part reflected back to the surface, in part transferred and in part absorbed. Most methods of near infrared (NIR) spectroscopy focus on the volume reflectance from a semi-infinite sample, while very few measure transmission. We have previously shown that examining the full scattering profile (angular distribution of exiting photons) provides more comprehensive information when measuring from a cylindrical tissue. Furthermore, an isobaric point was found which is not dependent on changes in the reduced scattering coefficient. The angle corresponding to this isobaric point depends on the tissue diameter. We investigated the role of multiple scattering and absorption on the full scattering profile of a cylindrical tissue. First, we define the range in which multiple scattering occurs for different tissue diameters. Next, we examine the role of the absorption coefficient in the attenuation of the full scattering profile. We demonstrate that the absorption linearly influences the intensity at each angle of the full scattering profile and, more importantly, the absorption does not change the position of the isobaric point. The findings of this work demonstrate a realistic model for optical tissue measurements such as NIR spectroscopy, PPG, and pulse oximetery.
Developing Teachers Who Are Reflective Practitioners: A Complex Process
ERIC Educational Resources Information Center
Ostorga, Alcione N.
2006-01-01
Teachers everywhere are being held accountable for their professional actions through the test-driven curricula sweeping the nation. The National Council for the Accreditation of Teacher Education (NCATE, 2002) makes it clear that promotion of reflective practice is an important component of teacher education programs. This multiple case study…
Ask Systems: Interrogative Access to Multiple Ways of Thinking
ERIC Educational Resources Information Center
Jonassen, David H.
2011-01-01
The purpose of this paper is to familiarize instructional designers and researchers with a useful design and research paradigm known as "Ask Systems." Ask Systems are interrogative interfaces to information and learning environments that model conversations with a skilled, reflective practitioner (Schon, The reflective practitioner, "1983") or…
"Meta-Talk" as a Composition Tool: Promoting Reflective Dialogue during the Drafting Process
ERIC Educational Resources Information Center
Song, Ah-Young
2017-01-01
This article argues for expanded opportunities for metalinguistic dialogue and written response rounds in order to better understand students' needs. Encouraging students to reflect on their compositions can invite multiple stylistic approaches and inform a more participatory composition process. The writing explores theoretical underpinnings,…
Feedback for Thought: Examining the Influence of Feedback Constituents on Learning Experience
ERIC Educational Resources Information Center
Aoun, Chadi; Vatanasakdakul, Savanid; Ang, Karyne
2018-01-01
Reflective teaching practice is often heralded as a pillar of effective tuition. However, the perceptions of multiple forms of feedback among learners and their contributions to reflective learning is yet to attract significant attention, particularly in the Information Systems (IS) context. This research investigates the antecedent constituents…
Andrew D. Bower; Bryce A. Richardson; Valerie Hipkins; Regina Rochefort; Carol Aubry
2011-01-01
Analysis of "neutral" molecular markers and "adaptive" quantitative traits are common methods of assessing genetic diversity and population structure. Molecular markers typically reflect the effects of demographic and stochastic processes but are generally assumed to not reflect natural selection. Conversely, quantitative (or "adaptive")...
Measurement of Far-Infrared Paint Emissivity for Reference Blackbody Modeling and Design
NASA Astrophysics Data System (ADS)
Kaplan, S. G.; Hanssen, L. M.; Mekhontsev, S. N.
2008-12-01
Blackbody sources are typically used for both ground-based and on-orbit calibration of infrared radiometers for atmospheric sounding. Accurate knowledge of the emissivity (or reflectivity) of the painted cavity surfaces is important for the design and modeling of the blackbody performance. Devices designed for the mid- to long-wave infrared (2 μm to 100 μm) generally use specular black paint and multiple (4 to 6) bounces to achieve high emissivity and uniform radiance over the required optical extent. To meet the CLARREO goal of long-term climate monitoring with an absolute uncertainty of < 0.1 K (3 σ), it will be necessary to calibrate radiance measurements to < 0.1 % uncertainty, which could require knowledge of paint emissivity with < 0.005 uncertainty at long wavelength. Critical material parameters include the dependence of emissivity on wavelength, angle of incidence, polarization, and temperature (200 K to 350 K), as well as contributions of scattered light. We present measurement methods and results in support of the CORSAIR SI-traceable far-infrared blackbody design, including temperature-dependent specular reflectance measurements out to 100 μm and angle-dependent data out to 25 μm. In addition, we describe the design for a proposed new facility at NIST (CBS3) that will enable hemispherical-directional emittance and reflectance measurements versus temperature and angle out to 100 μm.
Effect of surface deposits on electromagnetic propagation in uniform ducts
NASA Technical Reports Server (NTRS)
Baumeister, Kenneth J.
1991-01-01
A finite-element Galerkin formulation has been used to study the effect of material surface deposits on the reflective characteristics of straight uniform ducts with PEC (perfectly electric conducting) walls. Over a wide frequency range, the effect of both single and multiple dielectric surface deposits on the duct reflection coefficient were examined. The power reflection coefficient was found to be significantly increased by the addition of deposits on the wall.
NASA Technical Reports Server (NTRS)
Ustin, Susan L.; Sanderson, Eric W.; Grossman, Yaffa; Hart, Quinn J.
1993-01-01
Advances in imaging spectroscopy have indicated that remotely sensed reflectance measurements of the plant canopy may be used to identify and qualify some classes of canopy biochemicals; however, the manner in which differences in biochemical compositions translate into differences is not well understood. Most frequently, multiple linear regression routines have been used to correlate narrow band reflectance values with measured biochemical concentrations. Although some success has been achieved with such methods for given data sets, the bands selected by multiple regression are not consistent between data sets, nor is it always clear what physical or biological basis underlies the correlation. To examine the relationship between biochemical concentration and leaf reflectance signal we chose to focus on the visible spectrum where the primary biochemical absorbances are due to photosynthetic pigments. Pigments provide a range of absorbance features, occur over a range of concentrations in natural samples, and are ecophysiologically important. Concentrations of chlorophyll, for example, have been strongly correlated to foliar nitrogen levels within a species and to photosynthetic capacity across many species. In addition pigments effectively absorb most of the photosynthetically active radiation between 400-700 nm, a spectral region for which silicon detectors have good signal/noise characteristics. Our strategy has been to sample a variety of naturally occurring species to measure leaf reflectance and pigment compositions. We hope to extend our understanding of pigment reflectance effects to interpret small overlapping absorbances of other biochemicals in the infrared region. For this reason, selected samples were also tested to determine total nitrogen, crude protein, cellulose, and lignin levels. Leaf reflectance spectra measured with AVIRIS bandwidths and wavelengths were compared between species and within species and for differences between seasons, for changes in the the shape of the spectra. We attempt to statistically correlate these shape changes with differences in pigment compositions. In parallel with our comparisons of pigment composition and leaf reflectance, we have modified the PROSPECT leaf reflectance model to test the contributions of pigments or pigment group concentrations. PROSPECT considers a leaf as a multi-layer dielectric plane with an uneven surface. Jacquemoud adapted the basic analysis of Allen for surface effects, a leaf thickness factor, and the absorption of water and chlorophyll (actually all pigments) and the plant matrix. Our modifications to PROSPECT in the forward direction include breaking out the pigment concentration parameter into separate components for chlorophyll a and b and a number of xanthophylls and carotenes, and introducing a shift and convolution function to model the spread and shift from their in vitro measurements to their in vivo state. Further, we have considered how the matrix elements (i.e., all biochemicals and structural effects not modeled explicity) vary with species.
Tay, Wee Tek; Walsh, Thomas K.; Downes, Sharon; Anderson, Craig; Jermiin, Lars S.; Wong, Thomas K. F.; Piper, Melissa C.; Chang, Ester Silva; Macedo, Isabella Barony; Czepak, Cecilia; Behere, Gajanan T.; Silvie, Pierre; Soria, Miguel F.; Frayssinet, Marie; Gordon, Karl H. J.
2017-01-01
The Old World bollworm Helicoverpa armigera is now established in Brazil but efforts to identify incursion origin(s) and pathway(s) have met with limited success due to the patchiness of available data. Using international agricultural/horticultural commodity trade data and mitochondrial DNA (mtDNA) cytochrome oxidase I (COI) and cytochrome b (Cyt b) gene markers, we inferred the origins and incursion pathways into Brazil. We detected 20 mtDNA haplotypes from six Brazilian states, eight of which were new to our 97 global COI-Cyt b haplotype database. Direct sequence matches indicated five Brazilian haplotypes had Asian, African, and European origins. We identified 45 parsimoniously informative sites and multiple substitutions per site within the concatenated (945 bp) nucleotide dataset, implying that probabilistic phylogenetic analysis methods are needed. High diversity and signatures of uniquely shared haplotypes with diverse localities combined with the trade data suggested multiple incursions and introduction origins in Brazil. Increasing agricultural/horticultural trade activities between the Old and New Worlds represents a significant biosecurity risk factor. Identifying pest origins will enable resistance profiling that reflects countries of origin to be included when developing a resistance management strategy, while identifying incursion pathways will improve biosecurity protocols and risk analysis at biosecurity hotspots including national ports. PMID:28350004
Tay, Wee Tek; Walsh, Thomas K; Downes, Sharon; Anderson, Craig; Jermiin, Lars S; Wong, Thomas K F; Piper, Melissa C; Chang, Ester Silva; Macedo, Isabella Barony; Czepak, Cecilia; Behere, Gajanan T; Silvie, Pierre; Soria, Miguel F; Frayssinet, Marie; Gordon, Karl H J
2017-03-28
The Old World bollworm Helicoverpa armigera is now established in Brazil but efforts to identify incursion origin(s) and pathway(s) have met with limited success due to the patchiness of available data. Using international agricultural/horticultural commodity trade data and mitochondrial DNA (mtDNA) cytochrome oxidase I (COI) and cytochrome b (Cyt b) gene markers, we inferred the origins and incursion pathways into Brazil. We detected 20 mtDNA haplotypes from six Brazilian states, eight of which were new to our 97 global COI-Cyt b haplotype database. Direct sequence matches indicated five Brazilian haplotypes had Asian, African, and European origins. We identified 45 parsimoniously informative sites and multiple substitutions per site within the concatenated (945 bp) nucleotide dataset, implying that probabilistic phylogenetic analysis methods are needed. High diversity and signatures of uniquely shared haplotypes with diverse localities combined with the trade data suggested multiple incursions and introduction origins in Brazil. Increasing agricultural/horticultural trade activities between the Old and New Worlds represents a significant biosecurity risk factor. Identifying pest origins will enable resistance profiling that reflects countries of origin to be included when developing a resistance management strategy, while identifying incursion pathways will improve biosecurity protocols and risk analysis at biosecurity hotspots including national ports.
NASA Astrophysics Data System (ADS)
Tay, Wee Tek; Walsh, Thomas K.; Downes, Sharon; Anderson, Craig; Jermiin, Lars S.; Wong, Thomas K. F.; Piper, Melissa C.; Chang, Ester Silva; Macedo, Isabella Barony; Czepak, Cecilia; Behere, Gajanan T.; Silvie, Pierre; Soria, Miguel F.; Frayssinet, Marie; Gordon, Karl H. J.
2017-03-01
The Old World bollworm Helicoverpa armigera is now established in Brazil but efforts to identify incursion origin(s) and pathway(s) have met with limited success due to the patchiness of available data. Using international agricultural/horticultural commodity trade data and mitochondrial DNA (mtDNA) cytochrome oxidase I (COI) and cytochrome b (Cyt b) gene markers, we inferred the origins and incursion pathways into Brazil. We detected 20 mtDNA haplotypes from six Brazilian states, eight of which were new to our 97 global COI-Cyt b haplotype database. Direct sequence matches indicated five Brazilian haplotypes had Asian, African, and European origins. We identified 45 parsimoniously informative sites and multiple substitutions per site within the concatenated (945 bp) nucleotide dataset, implying that probabilistic phylogenetic analysis methods are needed. High diversity and signatures of uniquely shared haplotypes with diverse localities combined with the trade data suggested multiple incursions and introduction origins in Brazil. Increasing agricultural/horticultural trade activities between the Old and New Worlds represents a significant biosecurity risk factor. Identifying pest origins will enable resistance profiling that reflects countries of origin to be included when developing a resistance management strategy, while identifying incursion pathways will improve biosecurity protocols and risk analysis at biosecurity hotspots including national ports.
Sleep and Cognitive Function in Multiple Sclerosis.
Braley, Tiffany J; Kratz, Anna L; Kaplish, Neeraj; Chervin, Ronald D
2016-08-01
To examine associations between cognitive performance and polysomnographic measures of obstructive sleep apnea in patients with multiple sclerosis (MS). Participants underwent a comprehensive MS-specific cognitive testing battery (the Minimal Assessment of Cognitive Function in MS, or MACFIMS) and in-laboratory overnight PSG. In adjusted linear regression models, the oxygen desaturation index (ODI) and minimum oxygen saturation (MinO2) were significantly associated with performance on multiple MACFIMS measures, including the Paced Auditory Serial Addition Test (PASAT; 2-sec and 3-sec versions), which assesses working memory, processing speed, and attention, and on the Brief Visuospatial Memory Test-Revised, a test of delayed visual memory. The respiratory disturbance index (RDI) was also significantly associated with PASAT-3 scores as well as the California Verbal Learning Test-II (CVLT-II) Discriminability Index, a test of verbal memory and response inhibition. Among these associations, apnea severity measures accounted for between 12% and 23% of the variance in cognitive test performance. Polysomnographic measures of sleep fragmentation (as reflected by the total arousal index) and total sleep time also showed significant associations with a component of the CVLT-II that assesses response inhibition, explaining 18% and 27% of the variance in performance. Among patients with MS, obstructive sleep apnea and sleep disturbance are significantly associated with diminished visual memory, verbal memory, executive function (as reflected by response inhibition), attention, processing speed, and working memory. If sleep disorders degrade these cognitive functions, effective treatment could offer new opportunities to improve cognitive functioning in patients with MS. A commentary on this article appears in this issue on page 1489. © 2016 Associated Professional Sleep Societies, LLC.
NASA Astrophysics Data System (ADS)
Woo, Sungsoo; Kang, Sungsam; Yoon, Changhyeong; Choi, Wonshik
2016-03-01
With the advancement of 3D display technology, 3D imaging of macroscopic objects has drawn much attention as they provide the contents to display. The most widely used imaging methods include a depth camera, which measures time of flight for the depth discrimination, and various structured illumination techniques. However, these existing methods have poor depth resolution, which makes imaging complicated structures a difficult task. In order to resolve this issue, we propose an imaging system based upon low-coherence interferometry and off-axis digital holographic imaging. By using light source with coherence length of 200 micro, we achieved the depth resolution of 100 micro. In order to map the macroscopic objects with this high axial resolution, we installed a pair of prisms in the reference beam path for the long-range scanning of the optical path length. Specifically, one prism was fixed in position, and the other prism was mounted on a translation stage and translated in parallel to the first prism. Due to the multiple internal reflections between the two prisms, the overall path length was elongated by a factor of 50. In this way, we could cover a depth range more than 1 meter. In addition, we employed multiple speckle illuminations and incoherent averaging of the acquired holographic images for reducing the specular reflections from the target surface. Using this newly developed system, we performed imaging targets with multiple different layers and demonstrated imaging targets hidden behind the scattering layers. The method was also applied to imaging targets located around the corner.
Chung, Yi-Shih
2015-09-01
An increasing amount of evidence suggests that aberrant driving behaviors are not entirely rational. On the basis of the dual-process theory, this study postulates that drivers may learn to perform irrational aberrant driving behaviors, and these behaviors could be derived either from a deliberate or an intuitive decision-making approach. Accordingly, a seemingly irrational driving behavior model is proposed; in this model, the theory of planned behavior (TPB) was adopted to represent the deliberate decision-making mechanism, and habit strength was incorporated to reflect the intuitive decision process. A multiple trivariate mediation structure was designed to reflect the process through which driving behaviors are learned. Anticipated affective reactions (AARs) were further included to examine the effect of affect on aberrant driving behaviors. Considering the example of speeding behaviors, this study developed scales and conducted a two-wave survey of students in two departments at a university in Northern Taiwan. The analysis results show that habit strength consists of multiple aspects, and frequency of past behavior cannot be a complete repository for accumulating habit strength. Habit strength appeared to be a crucial mediator between intention antecedents (e.g., attitude) and the intention itself. Including habit strength in the TPB model enhanced the explained variance of speeding intention by 26.7%. In addition, AARs were different from attitudes; particularly, young drivers tended to perform speeding behaviors to reduce negative feelings such as regret. The proposed model provides an effective alternative approach for investigating aberrant driving behaviors; corresponding countermeasures are discussed. Copyright © 2015 Elsevier Ltd. All rights reserved.
Sirota, Miroslav; Juanchich, Marie
2018-03-27
The Cognitive Reflection Test, measuring intuition inhibition and cognitive reflection, has become extremely popular because it reliably predicts reasoning performance, decision-making, and beliefs. Across studies, the response format of CRT items sometimes differs, based on the assumed construct equivalence of tests with open-ended versus multiple-choice items (the equivalence hypothesis). Evidence and theoretical reasons, however, suggest that the cognitive processes measured by these response formats and their associated performances might differ (the nonequivalence hypothesis). We tested the two hypotheses experimentally by assessing the performance in tests with different response formats and by comparing their predictive and construct validity. In a between-subjects experiment (n = 452), participants answered stem-equivalent CRT items in an open-ended, a two-option, or a four-option response format and then completed tasks on belief bias, denominator neglect, and paranormal beliefs (benchmark indicators of predictive validity), as well as on actively open-minded thinking and numeracy (benchmark indicators of construct validity). We found no significant differences between the three response formats in the numbers of correct responses, the numbers of intuitive responses (with the exception of the two-option version, which had a higher number than the other tests), and the correlational patterns of the indicators of predictive and construct validity. All three test versions were similarly reliable, but the multiple-choice formats were completed more quickly. We speculate that the specific nature of the CRT items helps build construct equivalence among the different response formats. We recommend using the validated multiple-choice version of the CRT presented here, particularly the four-option CRT, for practical and methodological reasons. Supplementary materials and data are available at https://osf.io/mzhyc/ .
We characterized regional patterns of the tidal channel benthic diatom community and examined the relative importance of local wetland and surrounding landscape level factors measured at multiple scales in structuring this assemblage. Surrounding land cover was characterized at ...
NASA Astrophysics Data System (ADS)
Dettmer, J.; Quijano, J. E.; Dosso, S. E.; Holland, C. W.; Mandolesi, E.
2016-12-01
Geophysical seabed properties are important for the detection and classification of unexploded ordnance. However, current surveying methods such as vertical seismic profiling, coring, or inversion are of limited use when surveying large areas with high spatial sampling density. We consider surveys based on a source and receiver array towed by an autonomous vehicle which produce large volumes of seabed reflectivity data that contain unprecedented and detailed seabed information. The data are analyzed with a particle filter, which requires efficient reflection-coefficient computation, efficient inversion algorithms and efficient use of computer resources. The filter quantifies information content of multiple sequential data sets by considering results from previous data along the survey track to inform the importance sampling at the current point. Challenges arise from environmental changes along the track where the number of sediment layers and their properties change. This is addressed by a trans-dimensional model in the filter which allows layering complexity to change along a track. Efficiency is improved by likelihood tempering of various particle subsets and including exchange moves (parallel tempering). The filter is implemented on a hybrid computer that combines central processing units (CPUs) and graphics processing units (GPUs) to exploit three levels of parallelism: (1) fine-grained parallel computation of spherical reflection coefficients with a GPU implementation of Levin integration; (2) updating particles by concurrent CPU processes which exchange information using automatic load balancing (coarse grained parallelism); (3) overlapping CPU-GPU communication (a major bottleneck) with GPU computation by staggering CPU access to the multiple GPUs. The algorithm is applied to spherical reflection coefficients for data sets along a 14-km track on the Malta Plateau, Mediterranean Sea. We demonstrate substantial efficiency gains over previous methods. [This research was supported in part by the U.S. Dept of Defense, thought the Strategic Environmental Research and Development Program (SERDP).
Surface roughness effects on the solar reflectance of cool asphalt shingles
DOE Office of Scientific and Technical Information (OSTI.GOV)
Akbari, Hashem; Berdahl, Paul; Akbari, Hashem
2008-02-17
We analyze the solar reflectance of asphalt roofing shingles that are covered with pigmented mineral roofing granules. The reflecting surface is rough, with a total area approximately twice the nominal area. We introduce a simple analytical model that relates the 'micro-reflectance' of a small surface region to the 'macro-reflectance' of the shingle. This model uses a mean field approximation to account for multiple scattering effects. The model is then used to compute the reflectance of shingles with a mixture of different colored granules, when the reflectances of the corresponding mono-color shingles are known. Simple linear averaging works well, with smallmore » corrections to linear averaging derived for highly reflective materials. Reflective base granules and reflective surface coatings aid achievement of high solar reflectance. Other factors that influence the solar reflectance are the size distribution of the granules, coverage of the asphalt substrate, and orientation of the granules as affected by rollers during fabrication.« less
Pharmacokinetics-on-a-Chip Using Label-Free SERS Technique for Programmable Dual-Drug Analysis.
Fei, Jiayuan; Wu, Lei; Zhang, Yizhi; Zong, Shenfei; Wang, Zhuyuan; Cui, Yiping
2017-06-23
Synergistic effects of dual or multiple drugs have attracted great attention in medical fields, especially in cancer therapies. We provide a programmable microfluidic platform for pharmacokinetic detection of multiple drugs in multiple cells. The well-designed microfluidic platform includes two 2 × 3 microarrays of cell chambers, two gradient generators, and several pneumatic valves. Through the combined use of valves and gradient generators, each chamber can be controlled to infuse different kinds of living cells and drugs with specific concentrations as needed. In our experiments, 6-mercaptopurine (6MP) and methimazole (MMI) were chosen as two drug models and their pharmacokinetic parameters in different living cells were monitored through intracellular SERS spectra, which reflected the molecular structure of these drugs. The dynamic change of SERS fingerprints from 6MP and MMI molecules were recorded during drug metabolism in living cells. The results indicated that both 6MP and MMI molecules were diffused into the cells within 4 min and excreted out after 36 h. Moreover, the intracellular distribution of these drugs was monitored through SERS mapping. Thus, our microfluidic platform simultaneously accomplishes the functions to monitor pharmacokinetic action, distribution, and fingerprint of multiple drugs in multiple cells. Owing to its real-time, rapid-speed, high-precision, and programmable capability of multiple-drug and multicell analysis, such a microfluidic platform has great potential in drug design and development.
NASA Technical Reports Server (NTRS)
Tam, Christopher K. W.; Aganin, Alexei
2000-01-01
The transonic nozzle transmission problem and the open rotor noise radiation problem are solved computationally. Both are multiple length scales problems. For efficient and accurate numerical simulation, the multiple-size-mesh multiple-time-step Dispersion-Relation-Preserving scheme is used to calculate the time periodic solution. To ensure an accurate solution, high quality numerical boundary conditions are also needed. For the nozzle problem, a set of nonhomogeneous, outflow boundary conditions are required. The nonhomogeneous boundary conditions not only generate the incoming sound waves but also, at the same time, allow the reflected acoustic waves and entropy waves, if present, to exit the computation domain without reflection. For the open rotor problem, there is an apparent singularity at the axis of rotation. An analytic extension approach is developed to provide a high quality axis boundary treatment.
Al-Hallaq, Hania A; Chmura, Steven; Salama, Joseph K; Winter, Kathryn A; Robinson, Clifford G; Pisansky, Thomas M; Borges, Virginia; Lowenstein, Jessica R; McNulty, Susan; Galvin, James M; Followill, David S; Timmerman, Robert D; White, Julia R; Xiao, Ying; Matuszak, Martha M
In 2014, the NRG Oncology Group initiated the first National Cancer Institute-sponsored, phase 1 clinical trial of stereotactic body radiation therapy (SBRT) for the treatment of multiple metastases in multiple organ sites (BR001; NCT02206334). The primary endpoint is to test the safety of SBRT for the treatment of 2 to 4 multiple lesions in several anatomic sites in a multi-institutional setting. Because of the technical challenges inherent to treating multiple lesions as their spatial separation decreases, we present the technical requirements for NRG-BR001 and the rationale for their selection. Patients with controlled primary tumors of breast, non-small cell lung, or prostate are eligible if they have 2 to 4 metastases distributed among 7 extracranial anatomic locations throughout the body. Prescription and organ-at-risk doses were determined by expert consensus. Credentialing requirements include (1) irradiation of the Imaging and Radiation Oncology Core phantom with SBRT, (2) submitting image guided radiation therapy case studies, and (3) planning the benchmark. Guidelines for navigating challenging planning cases including assessing composite dose are discussed. Dosimetric planning to multiple lesions receiving differing doses (45-50 Gy) and fractionation (3-5) while irradiating the same organs at risk is discussed, particularly for metastases in close proximity (≤5 cm). The benchmark case was selected to demonstrate the planning tradeoffs required to satisfy protocol requirements for 2 nearby lesions. Examples of passing benchmark plans exhibited a large variability in plan conformity. NRG-BR001 was developed using expert consensus on multiple issues from the dose fractionation regimen to the minimum image guided radiation therapy guidelines. Credentialing was tied to the task rather than the anatomic site to reduce its burden. Every effort was made to include a variety of delivery methods to reflect current SBRT technology. Although some simplifications were adopted, the successful completion of this trial will inform future designs of both national and institutional trials and would allow immediate clinical adoption of SBRT trials for oligometastases. Copyright © 2016 American Society for Radiation Oncology. Published by Elsevier Inc. All rights reserved.
Developing Multiple Choice Tests: Tips & Techniques
ERIC Educational Resources Information Center
McCowan, Richard J.
1999-01-01
Item writing is a major responsibility of trainers. Too often, qualified staff who prepare lessons carefully and teach conscientiously use inadequate tests that do not validly reflect the true level of trainee achievement. This monograph describes techniques for constructing multiple-choice items that measure student performance accurately. It…
Omland, Torbjørn; White, Harvey D
2017-01-01
Multiple circulating biomarkers have been associated with the incidence of cardiovascular events and proposed as potential tools for risk stratification in stable ischemic heart disease (IHD), yet current guidelines do not make any firm recommendations concerning the use of biomarkers for risk stratification in this setting. This state-of-the-art review provides an overview of biomarkers for risk stratification in stable IHD. Circulating biomarkers associated with the risk of cardiovascular events in patients with stable IHD reflect different pathophysiological processes, including myocardial injury, myocardial stress and remodeling, metabolic status, vascular inflammation, and oxidative stress. Compared to the primary prevention setting, biomarkers reflecting end-organ damage and future risk of heart failure development and cardiovascular death may play more important roles in the stable IHD setting. Accordingly, biomarkers that reflect chronic, low-grade myocardial injury, and stress, i.e., high-sensitivity cardiac troponins and natriuretic peptides, provide graded and incremental prognostic information to conventional risk markers. In contrast, in stable IHD patients the prognostic value of traditional metabolic biomarkers, including serum lipids, is limited. Among several novel biomarkers, growth-differentiation factor-15 may provide the most robust prognostic information, whereas most inflammatory markers provide limited incremental prognostic information to risk factor models that include conventional risk factors, natriuretic peptides, and high-sensitivity troponins. Circulating biomarkers hold promise as useful tools for risk stratification in stable IHD, but their future incorporation into clinically useful risk scores will depend on prospective, rigorously performed clinical trials that document enhanced risk prediction. © 2016 American Association for Clinical Chemistry.
Murinson, Beth B.; Nenortas, Elizabeth; Mayer, R. Sam; Mezei, Lina; Kozachik, Sharon; Nesbit, Suzanne; Haythornthwaite, Jennifer A.; Campbell, James N.
2010-01-01
Objective Improvements in clinical pain care have not matched advances in scientific knowledge, and innovations in medical education are needed. Several streams of evidence indicate that pain education needs to address both the affective and cognitive dimensions of pain. Our aim was to design and deliver a new course in pain establishing foundation-level knowledge while comprehensively addressing the emotional development needs in this area. Setting 118 first year medical students at Johns Hopkins School of Medicine. Outcome measures Performance was measured by multiple choice tests of pain knowledge, attendance, reflective pain portfolios and satisfaction measures. Results Domains of competence in pain knowledge included central and peripheral pain signaling, pharmacological management of pain with standard analgesic medications, neuromodulating agents and opioids; cancer pain, musculoskeletal pain, nociceptive, inflammatory, neuropathic, geriatric, and pediatric pain. Socio-emotional development (portfolio) work focused on increasing awareness of pain affect in self and others and enhancing the commitment to excellence in pain care. Reflections included observations on a brief pain experience (cold pressor test), the multi-dimensionality of pain, the role of empathy and compassion in medical care, the positive characteristics of pain-care role models, the complex feelings engendered by pain and addiction including frustration and disappointment, and aspirations and commitments in clinical medicine. The students completing feedback expressed high levels of interest in pain medicine as a result of the course. Discussion We conclude that a four-day pain course incorporating sessions with pain- specialists, pain medicine knowledge, and design-built elements to strengthen emotional skills is an effective educational approach. PMID:21276187
Metacognition and the Development of Strategic Skills in Impulsive and Reflective Children.
ERIC Educational Resources Information Center
Kurtz, Beth E.; Borkowski, John G.
Examined were relationships between metamemory and strategic behavior in 130 impulsive and reflective children in fourth, fifth, and sixth grades. Of these, 77 had been tested 3 years earlier on multiple metamemory and memory tasks. At pretraining, children were assessed on metamemory, cognitive tempo, summarization skills, and teacher ratings of…
ERIC Educational Resources Information Center
Bell, Amani; Mladenovic, Rosina
2015-01-01
Despite tutors' importance, they often encounter inadequate professional development and support. This study describes the impact of peer observation of teaching activities on tutors' professional development using multiple data-sets over a three-year period. The data was analysed according to three themes: situated learning, reflective practice…
Multi-reflective acoustic wave device
Andle, Jeffrey C.
2006-02-21
An acoustic wave device, which utilizes multiple localized reflections of acoustic wave for achieving an infinite impulse response while maintaining high tolerance for dampening effects, is disclosed. The device utilized a plurality of electromechanically significant electrodes disposed on most of the active surface. A plurality of sensors utilizing the disclosed acoustic wave mode device are also described.
ERIC Educational Resources Information Center
Theadore, Geraldine; Laurent, Amy; Kovarsky, Dana; Weiss, Amy L.
2011-01-01
Reflective practice requires that professionals carefully examine and integrate multiple sources of information when designing intervention and evaluating its effectiveness. This article describes the use of focus group discussion as a form of qualitative research for understanding parents' perspectives of a university-based intervention program…
Iterated intracochlear reflection shapes the envelopes of basilar-membrane click responses
Shera, Christopher A.
2015-01-01
Multiple internal reflection of cochlear traveling waves has been argued to provide a plausible explanation for the waxing and waning and other temporal structures often exhibited by the envelopes of basilar-membrane (BM) and auditory-nerve responses to acoustic clicks. However, a recent theoretical analysis of a BM click response measured in chinchilla concludes that the waveform cannot have arisen via any equal, repetitive process, such as iterated intracochlear reflection [Wit and Bell (2015), J. Acoust. Soc. Am. 138, 94–96]. Reanalysis of the waveform contradicts this conclusion. The measured BM click response is used to derive the frequency-domain transfer function characterizing every iteration of the loop. The selfsame transfer function that yields waxing and waning of the BM click response also captures the spectral features of ear-canal stimulus-frequency otoacoustic emissions measured in the same animal, consistent with the predictions of multiple internal reflection. Small shifts in transfer-function phase simulate results at different measurement locations and reproduce the heterogeneity of BM click response envelopes observed experimentally. PMID:26723327
Duan, Ran; Semouchkina, Elena; Pandey, Ravi
2014-11-03
The geometric optics principles are used to develop a unidirectional transmission cloak for hiding objects with dimensions substantially exceeding the incident radiation wavelengths. Invisibility of both the object and the cloak is achieved without metamaterials, so that significant widths of the cloaking bands are provided. For the preservation of wave phases, the λ-multiple delays of waves passing through the cloak are realized. Suppression of reflection losses is achieved by using half-λ multiple thicknesses of optical elements. Due to periodicity of phase delay and reflection suppression conditions, the cloak demonstrates efficient multiband performance confirmed by full-wave simulations.
Emerging geomorphic approaches to guide river management practices
NASA Astrophysics Data System (ADS)
Brierley, Gary; Hooke, Janet
2015-12-01
Humans have been modifying river systems across much of the world for many thousands of years. Initially, piecemeal impacts inadvertently affected particular parts of landscapes. Subsequently, many rivers have been subjected to multiple layers of human disturbance, and changes have become widespread and systematic. Increasingly, human impacts reflect deliberative actions as part of river management programmes. These activities entail significant choices in determining the desirable (or acceptable) state and behavioural regime of a river. Typically, contemporary decision-making reflects negotiations among multiple stakeholders, seeking to provide balanced approaches to the management of socio-economic, cultural, and environmental values (e.g. Jähnig et al., 2011).
Lower Crstal Reflectity bands and Magma Emplacement in Norweigian sea, NE Atlantic
NASA Astrophysics Data System (ADS)
Rai, A.; Breivik, A. J.; Mjelde, R.
2013-12-01
In this study we present the OBS data collected along seismic profiles in the norweigian sea. The traveltime modelling of the OBS data provides first-hand information about seismic structure of the subsurface. However, waveform modelling is used to further constrain the fine scale structure, velocity constrast and velocity gradients. By forward modelling and inversion of the seismic waveforms, we show that the multiple bands of reflectivity could be due to multiple episodes of magma emplacements that might have frozen in the form of sills. These mafic intrusions probably intruded into the ductile lower crust during the main rifting phase of Europe and Greenland.
NASA Astrophysics Data System (ADS)
Abdelsalam, D. G.; Shaalan, M. S.; Eloker, M. M.; Kim, Daesuk
2010-06-01
In this paper a method is presented to accurately measure the radius of curvature of different types of curved surfaces of different radii of curvatures of 38 000,18 000 and 8000 mm using multiple-beam interference fringes in reflection. The images captured by the digital detector were corrected by flat fielding method. The corrected images were analyzed and the form of the surfaces was obtained. A 3D profile for the three types of surfaces was obtained using Zernike polynomial fitting. Some sources of uncertainty in measurement were calculated by means of ray tracing simulations and the uncertainty budget was estimated within λ/40.
Estimated Mid-Infrared (200-2000 cm-1) Optical Constants of Some Silica Polymorphs
NASA Astrophysics Data System (ADS)
Glotch, Timothy; Rossman, G. R.; Michalski, J. R.
2006-09-01
We use Lorentz-Lorenz dispersion analysis to model the mid-infrared (200-2000 cm-1) optical constants, of opal-A, opal-CT, and tridymite. These minerals, which are all polymorphs of silica (SiO2), are potentially important in the analysis of thermal emission spectra acquired by the Mars Global Surveyor Thermal Emission Spectrometer (MGS-TES) and Mars Exploration Rover Mini-TES instruments in orbit and on the surface of Mars as well as emission spectra acquired by telescopes of planetary disks and dust and debris clouds in young solar systems. Mineral samples were crushed, washed, and sieved and emissivity spectra of the >100; μm size fraction were acquired at Arizona State University's emissivity spectroscopy laboratory. Therefore, the spectra and optical constants are representative of all crystal orientations. Ideally, emissivity or reflectance measurements of single polished crystals or fine powders pressed to compact disks are used for the determination of mid-infrared optical constants. Measurements of these types of surfaces eliminate or minimize multiple reflections, providing a specular surface. Our measurements, however, likely produce a reasonable approximation of specular emissivity or reflectance, as the minimum particle size is greater than the maximum wavelength of light measured. Future work will include measurement of pressed disks of powdered samples in emission and reflection, and when possible, small single crystals under an IR reflectance microscope, which will allow us to assess the variability of spectra and optical constants under different sample preparation and measurement conditions.
NASA Astrophysics Data System (ADS)
Haefner, Leigh Boardman
2001-10-01
This study examined prospective elementary teachers' learning about science inquiry in the context of an innovative life science course that engaged them in an original science investigation. Eleven elementary education majors participated in the study. A multiple case study approach that was descriptive, interpretive, and framed by grounded theory was employed. Primary data sources included transcripts of semi-structured interviews, text associated with online threaded discussions, and course project documents, such as lesson plans and written reflections. Secondary data sources included videotaped class sessions and field notes. Data were analyzed using analytical induction techniques, and trustworthiness was developed through the use of multiple data sources, triangulation of data, and the use of counterexamples to the assertions. Three major findings emerged from the cross-case analysis. First, engaging in an original science investigation assisted prospective teachers in becoming more attentive to the processes of science and developing more elaborated and data-driven explanations of how science is practiced. Second, when prospective teachers struggled with particular aspects of their investigations, those aspects became foci of change in their thinking about science and doing science. Third, as prospective teachers came to place a greater emphasis on questions, observations, and experimentation as fundamental aspects of doing science, they became more accepting of approaches to teaching science that encourage children's questions about science phenomena. Implications include the need to re-conceptualize teacher preparation programs to include multiple opportunities to engage prospective teachers in learning science as inquiry, and attend to connections among subject matter knowledge, subject-specific pedagogy and experiences with children.
Reflective practice in speech-language pathology: a scoping review.
Caty, Marie-Ève; Kinsella, Elizabeth Anne; Doyle, Philip C
2015-01-01
Within the profession of speech-language pathology, there is limited information related to both conceptual and empirical perspectives of reflective practice. This review considers the key concepts and approaches to reflection and reflective practice that have been published in the speech-language pathology literature in order to identify potential research gaps. A scoping review was conducted using Arksey and O'Malley's (2005) framework. A total of 42 relevant publications were selected for review. The resulting literature mapping revealed that scholarship on reflection and reflective practice in speech-language pathology is limited. Our conceptual mapping pointed to the use of both multiple and generic terms and a lack of conceptual clarity about reflection and reflective practice in speech-language pathology. Two predominant approaches to reflection and reflective practice were identified: written reflection and reflective discussion. Both educational and clinical practice contexts were associated with reflection and reflective practice. Publications reviewed were primarily concerned with reflection and reflective practice by novices and expert practitioners. Based on this review, we posit that there is considerable need for conceptual and empirical work with a goal to support university- and work-based educational initiatives involving reflection and reflective practice in speech-language pathology.
González-Gascón Y Marín, Isabel; Hernández-Sanchez, María; Rodríguez-Vicente, Ana Eugenia; Puiggros, Anna; Collado, Rosa; Luño, Elisa; González, Teresa; Ruiz-Xivillé, Neus; Ortega, Margarita; Gimeno, Eva; Muñoz, Carolina; Infante, Maria Stefania; Delgado, Julio; Vargas, María Teresa; González, Marcos; Bosch, Francesc; Espinet, Blanca; Hernández-Rivas, Jesús María; Hernández, José Ángel
2018-03-01
We analyzed the features of chronic lymphocytic leukemia (CLL) with multiple abnormalities (MA) detected by FISH. A local database including 2095 CLL cases was used and 323 with MA (15.4%) were selected. MA was defined by the presence of two or more alterations (deletions of 13q14 (13q-), 11q22 (11q-), 17p13 (17p-) or trisomy 12 (+12)). The combination of 13q- with 11q- and 13q- with 17p-, accounted for 58.2% of the series, in contrast to 11q- with 17p- (3.7%). Patients carrying MA since diagnosis presented a short time to first therapy(TTFT) (27 months) and overall survival (OS) (76 months). The combinations including 17p- had a shorter OS (58 months) than the ones without 17p- (not reached, p = .002). Patients with a complex-FISH were the ones with worse OS (34 months). MA imply poor prognosis when they emerge at diagnosis, probably due to the high incidence of bad prognosis markers, which may be a reflection of a more complex karyotype.
NDE Imaging of Time Differential Terahertz Waves
NASA Technical Reports Server (NTRS)
Trinh, Long B.
2008-01-01
Natural voids are present in the vicinity of a conathane interface that bonds two different foam materials. These voids are out of focus with the terahertz imaging system and multiple optical reflections also make it difficult to determine their depths. However, waves passing through the top foam article at normal incidence are partially reflected at the denser conathane layer prior to total reflection at the tank s wall. Reflections embedded in the oscillating noise segment prior to the main signals can be extracted with dual applications of filtering and time derivative. Void's depth is computed from direct path's time of flight.
Hockett, Jericho M; Saucier, Donald A; Badke, Caitlyn
2016-03-01
Rape is prevalent at colleges. Although research suggests commonalities across many college women's rape experiences (e.g., perpetrators using multiple coercive strategies), vignettes used to assess rape perceptions often reflect false beliefs. Two studies varying a perpetrator's coercive tactics examine rape perceptions using vignettes reflecting rape myths, rape scripts, or many college women's common rape experiences. Participants perceive a woman who was raped more positively in vignettes reflecting common rape experiences versus those reflecting rape myths or scripts. Theoretical, educational, and research implications are discussed. © The Author(s) 2015.
Interferometric imaging of crustal structure from wide-angle multicomponent OBS-airgun data
NASA Astrophysics Data System (ADS)
Shiraishi, K.; Fujie, G.; Sato, T.; Abe, S.; Asakawa, E.; Kodaira, S.
2015-12-01
In wide-angle seismic surveys with ocean bottom seismograph (OBS) and airgun, surface-related multiple reflections and upgoing P-to-S conversions are frequently observed. We applied two interferometric imaging methods to the multicomponent OBS data in order to highly utilize seismic signals for subsurface imaging.First, seismic interferometry (SI) is applied to vertical component in order to obtain reflection profile with multiple reflections. By correlating seismic traces on common receiver records, pseudo seismic data are generated with virtual sources and receivers located on all original shot positions. We adopt the deconvolution SI because source and receiver spectra can be canceled by spectral division. Consequently, gapless reflection images from just below the seafloor to the deeper are obtained.Second, receiver function (RF) imaging is applied to multicomponent OBS data in order to image P-to-S conversion boundary. Though RF is commonly applied to teleseismic data, our purpose is to extract upgoing PS converted waves from wide-angle OBS data. The RF traces are synthesized by deconvolution of radial and vertical components at same OBS location for each shot. Final section obtained by stacking RF traces shows the PS conversion boundaries beneath OBSs. Then, Vp/Vs ratio can be estimated by comparing one-way traveltime delay with two-way traveltime of P wave reflections.We applied these methods to field data sets; (a) 175 km survey in Nankai trough subduction zone using 71 OBSs with from 1 km to 10 km intervals and 878 shots with 200 m interval, and (b) 237 km survey in northwest pacific ocean with almost flat layers before subduction using 25 OBSs with 6km interval and 1188 shots with 200 m interval. In our study, SI imaging with multiple reflections is highly applicable to OBS data even in a complex geological setting, and PS conversion boundary is well imaged by RF imaging and Vp/Vs ratio distribution in sediment is estimated in case of simple structure.
ERIC Educational Resources Information Center
Lee, Jimin; Hustad, Katherine C.; Weismer, Gary
2014-01-01
Purpose: Speech acoustic characteristics of children with cerebral palsy (CP) were examined with a multiple speech subsystems approach; speech intelligibility was evaluated using a prediction model in which acoustic measures were selected to represent three speech subsystems. Method: Nine acoustic variables reflecting different subsystems, and…
Valuing Assessment in Teacher Education - Multiple-Choice Competency Testing
ERIC Educational Resources Information Center
Martin, Dona L.; Itter, Diane
2014-01-01
When our focus is on assessment educators should work to value the nature of assessment. This paper presents a new approach to multiple-choice competency testing in mathematics education. The instrument discussed here reflects student competence, encourages self-regulatory learning behaviours and links content with current curriculum documents and…
Student Selection for Selective Educational Programs Using Multiple Criteria.
ERIC Educational Resources Information Center
Jenkins, Jerry A.
This paper shows that multiple sources of data reflecting educational progress may be used with relative ease to systematically, objectively, and accurately place students in selective educational programs, such as those funded under Chapter 1 of the Education Consolidation and Improvement Act, using readily available commercial microcomputer…
Multiple Beam Interferometry in Elementary Teaching
ERIC Educational Resources Information Center
Tolansky, S.
1970-01-01
Discusses a relatively simple technique for demonstrating multiple beam interferometry. The technique can be applied to measuring (1) radii of curvature of lenses, (2) surface finish of glass, and (3) differential phase change on reflection. Microtopographies, modulated fringe systems and opaque objects may also be observed by this technique.…
Ecological Issues Related to Children's Health and Safety
ERIC Educational Resources Information Center
Aldridge, Jerry; Kohler, Maxie
2009-01-01
Issues concerning the health and safety of children and youth occur at multiple levels. Bronfenbrenner (1995) proposed an ecological systems approach in which multiple systems interact to enhance or diminish children's development. The same systems are at work in health promotion. The authors present and review articles that reflect the multiple…
Adolescent Racial Identity: Self-Identification of Multiple and "Other" Race/Ethnicities
ERIC Educational Resources Information Center
Harris, Bryn; Ravert, Russell D.; Sullivan, Amanda L.
2017-01-01
This mixed methods study focused on adolescents who rejected conventional singular racial/ethnic categorization by selecting multiple race/ethnicities or writing descriptions of "Other" racial/ethnic identities in response to a survey item asking them to identify their race/ethnicity. Written responses reflected eight distinct categories…
Spatial organization of hominin activities at Gesher Benot Ya'aqov, Israel.
Alperson-Afil, Nira; Sharon, Gonen; Kislev, Mordechai; Melamed, Yoel; Zohar, Irit; Ashkenazi, Shosh; Rabinovich, Rivka; Biton, Rebecca; Werker, Ella; Hartman, Gideon; Feibel, Craig; Goren-Inbar, Naama
2009-12-18
The spatial designation of discrete areas for different activities reflects formalized conceptualization of a living space. The results of spatial analyses of a Middle Pleistocene Acheulian archaeological horizon (about 750,000 years ago) at Gesher Benot Ya'aqov, Israel, indicate that hominins differentiated their activities (stone knapping, tool use, floral and faunal processing and consumption) across space. These were organized in two main areas, including multiple activities around a hearth. The diversity of human activities and the distinctive patterning with which they are organized implies advanced organizational skills of the Gesher Benot Ya'aqov hominins.
Collective Lamb Shift of a Nanoscale Atomic Vapor Layer within a Sapphire Cavity
NASA Astrophysics Data System (ADS)
Peyrot, T.; Sortais, Y. R. P.; Browaeys, A.; Sargsyan, A.; Sarkisyan, D.; Keaveney, J.; Hughes, I. G.; Adams, C. S.
2018-06-01
We measure the near-resonant transmission of light through a dense medium of potassium vapor confined in a cell with nanometer thickness in order to investigate the origin and validity of the collective Lamb shift. A complete model including the multiple reflections in the nanocell reproduces accurately the observed line shape. It allows the extraction of a density-dependent shift and width of the bulk atomic medium resonance, deconvolved from the cavity effect. We observe an additional, unexpected dependence of the shift with the thickness of the medium. This extra dependence demands further experimental and theoretical investigations.
How Exemplary Inpatient Teaching Physicians Foster Clinical Reasoning.
Houchens, Nathan; Harrod, Molly; Fowler, Karen E; Moody, Stephanie; Saint, Sanjay
2017-09-01
Clinical reasoning is a crucial component of training in health professions. These cognitive skills are necessary to provide quality care and avoid diagnostic error. Much previous literature has focused on teaching clinical reasoning in nonclinical environments and does not include learner reflections. The authors sought to explore, through multiple perspectives including learners, techniques used by exemplary inpatient clinician-educators for explicitly cultivating clinical reasoning. The authors conducted (2014-2015) a multisite, exploratory qualitative study examining how excellent clinician-educators foster clinical reasoning during general medicine rounds. This was accomplished through interviews of educators, focus group discussions with learners, and direct observations of clinical teaching. The authors reviewed field notes and transcripts using techniques of thematic analysis. Twelve clinician-educators, 57 current learners, and 26 former learners participated in observations and interviews. The techniques and behaviors of educators were categorized into 4 themes, including 1) emphasizing organization and prioritization, 2) accessing prior knowledge, 3) thinking aloud, and 4) analyzing the literature. The findings of this comprehensive study both confirm strategies found in previous literature and provide novel approaches. This is the first study to incorporate the perspectives of learners. Educators' techniques and behaviors, identified through direct observation and supported by reflections from the entire team, can inform best practices for the teaching of clinical reasoning. Copyright © 2017 Elsevier Inc. All rights reserved.
The Functional Role of Neural Oscillations in Non-Verbal Emotional Communication
Symons, Ashley E.; El-Deredy, Wael; Schwartze, Michael; Kotz, Sonja A.
2016-01-01
Effective interpersonal communication depends on the ability to perceive and interpret nonverbal emotional expressions from multiple sensory modalities. Current theoretical models propose that visual and auditory emotion perception involves a network of brain regions including the primary sensory cortices, the superior temporal sulcus (STS), and orbitofrontal cortex (OFC). However, relatively little is known about how the dynamic interplay between these regions gives rise to the perception of emotions. In recent years, there has been increasing recognition of the importance of neural oscillations in mediating neural communication within and between functional neural networks. Here we review studies investigating changes in oscillatory activity during the perception of visual, auditory, and audiovisual emotional expressions, and aim to characterize the functional role of neural oscillations in nonverbal emotion perception. Findings from the reviewed literature suggest that theta band oscillations most consistently differentiate between emotional and neutral expressions. While early theta synchronization appears to reflect the initial encoding of emotionally salient sensory information, later fronto-central theta synchronization may reflect the further integration of sensory information with internal representations. Additionally, gamma synchronization reflects facilitated sensory binding of emotional expressions within regions such as the OFC, STS, and, potentially, the amygdala. However, the evidence is more ambiguous when it comes to the role of oscillations within the alpha and beta frequencies, which vary as a function of modality (or modalities), presence or absence of predictive information, and attentional or task demands. Thus, the synchronization of neural oscillations within specific frequency bands mediates the rapid detection, integration, and evaluation of emotional expressions. Moreover, the functional coupling of oscillatory activity across multiples frequency bands supports a predictive coding model of multisensory emotion perception in which emotional facial and body expressions facilitate the processing of emotional vocalizations. PMID:27252638
The Functional Role of Neural Oscillations in Non-Verbal Emotional Communication.
Symons, Ashley E; El-Deredy, Wael; Schwartze, Michael; Kotz, Sonja A
2016-01-01
Effective interpersonal communication depends on the ability to perceive and interpret nonverbal emotional expressions from multiple sensory modalities. Current theoretical models propose that visual and auditory emotion perception involves a network of brain regions including the primary sensory cortices, the superior temporal sulcus (STS), and orbitofrontal cortex (OFC). However, relatively little is known about how the dynamic interplay between these regions gives rise to the perception of emotions. In recent years, there has been increasing recognition of the importance of neural oscillations in mediating neural communication within and between functional neural networks. Here we review studies investigating changes in oscillatory activity during the perception of visual, auditory, and audiovisual emotional expressions, and aim to characterize the functional role of neural oscillations in nonverbal emotion perception. Findings from the reviewed literature suggest that theta band oscillations most consistently differentiate between emotional and neutral expressions. While early theta synchronization appears to reflect the initial encoding of emotionally salient sensory information, later fronto-central theta synchronization may reflect the further integration of sensory information with internal representations. Additionally, gamma synchronization reflects facilitated sensory binding of emotional expressions within regions such as the OFC, STS, and, potentially, the amygdala. However, the evidence is more ambiguous when it comes to the role of oscillations within the alpha and beta frequencies, which vary as a function of modality (or modalities), presence or absence of predictive information, and attentional or task demands. Thus, the synchronization of neural oscillations within specific frequency bands mediates the rapid detection, integration, and evaluation of emotional expressions. Moreover, the functional coupling of oscillatory activity across multiples frequency bands supports a predictive coding model of multisensory emotion perception in which emotional facial and body expressions facilitate the processing of emotional vocalizations.
NASA Technical Reports Server (NTRS)
Yon, S. A.; Pieters, C. M.
1988-01-01
The nature of the interactions of visible and NIR radiation with the surfaces of rock and mineral samples was investigated by measuring the reflectance and the polarization properties of scattered and reflected light for slab samples of obsidian and fine-grained basalt, prepared to controlled surface roughness. It is shown that the degree to which radiation can penetrate a surface and then scatter back out, an essential criterion for mineralogic determinations based on reflectance spectra, depends not only upon the composition of the material, but also on its physical condition such as sample grain size and surface roughness. Comparison of the experimentally measured reflectance and polarization from smooth and rough slab materials with the predicted models indicates that single Fresnel reflections are responsible for the largest part of the reflected intensity resulting from interactions with the surfaces of dielectric materials; multiple Fresnel reflections are much less important for such surfaces.
Action-specific effects in aviation: what determines judged runway size?
Gray, Rob; Navia, José Antonio; Allsop, Jonathan
2014-01-01
Several recent studies have shown that the performance of a skill that involves acting on a goal object can influence one's judgment of the size of that object. The present study investigated this effect in an aviation context. Novice pilots were asked to perform a series of visual approach and landing manoeuvres in a flight simulator. After each landing, participants next performed a task in which runway size was judged for different simulated altitudes. Gaze behaviour and control stick kinematics were also analyzed. There were significant relationships between judged runway size and multiple action-related variables including touchdown velocity, time fixating the runway, and the magnitude and frequency of control inputs. These findings suggest that relationship between the perception of a target object and action is not solely determined by performance success or failure but rather involves a relationship between multiple variables that reflect the actor's ability.
Meteorological adjustment of yearly mean values for air pollutant concentration comparison
NASA Technical Reports Server (NTRS)
Sidik, S. M.; Neustadter, H. E.
1976-01-01
Using multiple linear regression analysis, models which estimate mean concentrations of Total Suspended Particulate (TSP), sulfur dioxide, and nitrogen dioxide as a function of several meteorologic variables, two rough economic indicators, and a simple trend in time are studied. Meteorologic data were obtained and do not include inversion heights. The goodness of fit of the estimated models is partially reflected by the squared coefficient of multiple correlation which indicates that, at the various sampling stations, the models accounted for about 23 to 47 percent of the total variance of the observed TSP concentrations. If the resulting model equations are used in place of simple overall means of the observed concentrations, there is about a 20 percent improvement in either: (1) predicting mean concentrations for specified meteorological conditions; or (2) adjusting successive yearly averages to allow for comparisons devoid of meteorological effects. An application to source identification is presented using regression coefficients of wind velocity predictor variables.
Defining the clinical course of multiple sclerosis
Reingold, Stephen C.; Cohen, Jeffrey A.; Cutter, Gary R.; Sørensen, Per Soelberg; Thompson, Alan J.; Wolinsky, Jerry S.; Balcer, Laura J.; Banwell, Brenda; Barkhof, Frederik; Bebo, Bruce; Calabresi, Peter A.; Clanet, Michel; Comi, Giancarlo; Fox, Robert J.; Freedman, Mark S.; Goodman, Andrew D.; Inglese, Matilde; Kappos, Ludwig; Kieseier, Bernd C.; Lincoln, John A.; Lubetzki, Catherine; Miller, Aaron E.; Montalban, Xavier; O'Connor, Paul W.; Petkau, John; Pozzilli, Carlo; Rudick, Richard A.; Sormani, Maria Pia; Stüve, Olaf; Waubant, Emmanuelle; Polman, Chris H.
2014-01-01
Accurate clinical course descriptions (phenotypes) of multiple sclerosis (MS) are important for communication, prognostication, design and recruitment of clinical trials, and treatment decision-making. Standardized descriptions published in 1996 based on a survey of international MS experts provided purely clinical phenotypes based on data and consensus at that time, but imaging and biological correlates were lacking. Increased understanding of MS and its pathology, coupled with general concern that the original descriptors may not adequately reflect more recently identified clinical aspects of the disease, prompted a re-examination of MS disease phenotypes by the International Advisory Committee on Clinical Trials of MS. While imaging and biological markers that might provide objective criteria for separating clinical phenotypes are lacking, we propose refined descriptors that include consideration of disease activity (based on clinical relapse rate and imaging findings) and disease progression. Strategies for future research to better define phenotypes are also outlined. PMID:24871874
Photonic Doppler velocimetry lens array probe incorporating stereo imaging
Malone, Robert M.; Kaufman, Morris I.
2015-09-01
A probe including a multiple lens array is disclosed to measure velocity distribution of a moving surface along many lines of sight. Laser light, directed to the moving surface is reflected back from the surface and is Doppler shifted, collected into the array, and then directed to detection equipment through optic fibers. The received light is mixed with reference laser light and using photonic Doppler velocimetry, a continuous time record of the surface movement is obtained. An array of single-mode optical fibers provides an optic signal to the multiple lens array. Numerous fibers in a fiber array project numerous rays to establish many measurement points at numerous different locations. One or more lens groups may be replaced with imaging lenses so a stereo image of the moving surface can be recorded. Imaging a portion of the surface during initial travel can determine whether the surface is breaking up.
Reduction of background clutter in structured lighting systems
Carlson, Jeffrey J.; Giles, Michael K.; Padilla, Denise D.; Davidson, Jr., Patrick A.; Novick, David K.; Wilson, Christopher W.
2010-06-22
Methods for segmenting the reflected light of an illumination source having a characteristic wavelength from background illumination (i.e. clutter) in structured lighting systems can comprise pulsing the light source used to illuminate a scene, pulsing the light source synchronously with the opening of a shutter in an imaging device, estimating the contribution of background clutter by interpolation of images of the scene collected at multiple spectral bands not including the characteristic wavelength and subtracting the estimated background contribution from an image of the scene comprising the wavelength of the light source and, placing a polarizing filter between the imaging device and the scene, where the illumination source can be polarized in the same orientation as the polarizing filter. Apparatus for segmenting the light of an illumination source from background illumination can comprise an illuminator, an image receiver for receiving images of multiple spectral bands, a processor for calculations and interpolations, and a polarizing filter.
Small RNAs Reflect Grandparental Environments in Apomictic Dandelion
Morgado, Lionel; Preite, Veronica; Oplaat, Carla; Anava, Sarit; Ferreira de Carvalho, Julie; Rechavi, Oded; Johannes, Frank; Verhoeven, Koen J.F.
2017-01-01
Abstract Plants can show long-term effects of environmental stresses and in some cases a stress “memory” has been reported to persist across generations, potentially mediated by epigenetic mechanisms. However, few documented cases exist of transgenerational effects that persist for multiple generations and it remains unclear if or how epigenetic mechanisms are involved. Here, we show that the composition of small regulatory RNAs in apomictic dandelion lineages reveals a footprint of drought stress and salicylic acid treatment experienced two generations ago. Overall proportions of 21 and 24 nt RNA pools were shifted due to grandparental treatments. While individual genes did not show strong up- or downregulation of associated sRNAs, the subset of genes that showed the strongest shifts in sRNA abundance was significantly enriched for several GO terms including stress-specific functions. This suggests that a stress-induced signal was transmitted across multiple unexposed generations leading to persistent changes in epigenetic gene regulation. PMID:28472380
Helping students learn effective problem solving strategies by reflecting with peers
NASA Astrophysics Data System (ADS)
Mason, Andrew; Singh, Chandralekha
2010-07-01
We study how introductory physics students engage in reflection with peers about problem solving. The recitations for an introductory physics course with 200 students were broken into a "peer reflection" (PR) group and a traditional group. Each week in recitation, small teams of students in the PR group reflected on selected problems from the homework and discussed why the solutions of some students employed better problem solving strategies than others. The graduate and undergraduate teaching assistants in the PR recitations provided guidance and coaching to help students learn effective problem solving heuristics. In the traditional group recitations students could ask the graduate TA questions about the homework before they took a weekly quiz. The traditional group recitation quiz questions were similar to the homework questions selected for peer reflection in the PR group recitations. As one measure of the impact of this intervention, we investigated how likely students were to draw diagrams to help with problem solving on the final exam with only multiple-choice questions. We found that the PR group drew diagrams on more problems than the traditional group even when there was no explicit reward for doing so. Also, students who drew more diagrams for the multiple-choice questions outperformed those who did not, regardless of which group they were a member.
Spectroscopic sensitivity of real-time, rapidly induced phytochemical change in response to damage.
Couture, John J; Serbin, Shawn P; Townsend, Philip A
2013-04-01
An ecological consequence of plant-herbivore interactions is the phytochemical induction of defenses in response to insect damage. Here, we used reflectance spectroscopy to characterize the foliar induction profile of cardenolides in Asclepias syriaca in response to damage, tracked in vivo changes and examined the influence of multiple plant traits on cardenolide concentrations. Foliar cardenolide concentrations were measured at specific time points following damage to capture their induction profile. Partial least-squares regression (PLSR) modeling was employed to calibrate cardenolide concentrations to reflectance spectroscopy. In addition, subsets of plants were either repeatedly sampled to track in vivo changes or modified to reduce latex flow to damaged areas. Cardenolide concentrations and the induction profile of A. syriaca were well predicted using models derived from reflectance spectroscopy, and this held true for repeatedly sampled plants. Correlations between cardenolides and other foliar-related variables were weak or not significant. Plant modification for latex reduction inhibited an induced cardenolide response. Our findings show that reflectance spectroscopy can characterize rapid phytochemical changes in vivo. We used reflectance spectroscopy to identify the mechanisms behind the production of plant secondary metabolites, simultaneously characterizing multiple foliar constituents. In this case, cardenolide induction appears to be largely driven by enhanced latex delivery to leaves following damage. © 2013 The Authors. New Phytologist © 2013 New Phytologist Trust.
Baird, Kathleen; Salmon, Debra
2012-12-01
this exploratory work examined and assessed the experiences of participants (n=90) using an interactive drama workshop to facilitate the planning and understanding of multiagency working around domestic violence during pregnancy. a descriptive research design was utilised to collect data from field observations, participant reflective feedback sheets and semi-structured telephone interviews. participants invited to the workshop originated from a wide range of backgrounds including health and social care, criminal justice and the third sector. All participants were invited to complete the reflective feedback evaluation form. To enhance the comprehensiveness of the enquiry, semi-structured interviews were also conducted with 10 of the participants. shared themes emerging from the data analysis included improved awareness of the consequences of domestic violence; greater understanding of multiple professional roles including the policy context and enhanced skill development. However, participants questioned the extent to which this approach impacted upon longer term practice and policy development. by centring attention on the emic perspective of women themselves, the drama approach developed professional's awareness, relationships, understanding and skills. Nevertheless, drama can be an expensive education tool. It is therefore essential that further research explores the longer term impacts on practice and outcomes for women that include cost-benefit analysis. Copyright © 2011 Elsevier Ltd. All rights reserved.
A Generic Authentication LoA Derivation Model
NASA Astrophysics Data System (ADS)
Yao, Li; Zhang, Ning
One way of achieving a more fine-grained access control is to link an authentication level of assurance (LoA) derived from a requester’s authentication instance to the authorisation decision made to the requester. To realise this vision, there is a need for designing a LoA derivation model that supports the use and quantification of multiple LoA-effecting attributes, and analyse their composite effect on a given authentication instance. This paper reports the design of such a model, namely a generic LoA derivation model (GEA- LoADM). GEA-LoADM takes into account of multiple authentication attributes along with their relationships, abstracts the composite effect by the multiple attributes into a generic value, authentication LoA, and provides algorithms for the run-time derivation of LoA. The algorithms are tailored to reflect the relationships among the attributes involved in an authentication instance. The model has a number of valuable properties, including flexibility and extensibility; it can be applied to different application contexts and support easy addition of new attributes and removal of obsolete ones.
Cooperative Robots to Observe Moving Targets: Review.
Khan, Asif; Rinner, Bernhard; Cavallaro, Andrea
2018-01-01
The deployment of multiple robots for achieving a common goal helps to improve the performance, efficiency, and/or robustness in a variety of tasks. In particular, the observation of moving targets is an important multirobot application that still exhibits numerous open challenges, including the effective coordination of the robots. This paper reviews control techniques for cooperative mobile robots monitoring multiple targets. The simultaneous movement of robots and targets makes this problem particularly interesting, and our review systematically addresses this cooperative multirobot problem for the first time. We classify and critically discuss the control techniques: cooperative multirobot observation of multiple moving targets, cooperative search, acquisition, and track, cooperative tracking, and multirobot pursuit evasion. We also identify the five major elements that characterize this problem, namely, the coordination method, the environment, the target, the robot and its sensor(s). These elements are used to systematically analyze the control techniques. The majority of the studied work is based on simulation and laboratory studies, which may not accurately reflect real-world operational conditions. Importantly, while our systematic analysis is focused on multitarget observation, our proposed classification is useful also for related multirobot applications.
KAMO: towards automated data processing for microcrystals.
Yamashita, Keitaro; Hirata, Kunio; Yamamoto, Masaki
2018-05-01
In protein microcrystallography, radiation damage often hampers complete and high-resolution data collection from a single crystal, even under cryogenic conditions. One promising solution is to collect small wedges of data (5-10°) separately from multiple crystals. The data from these crystals can then be merged into a complete reflection-intensity set. However, data processing of multiple small-wedge data sets is challenging. Here, a new open-source data-processing pipeline, KAMO, which utilizes existing programs, including the XDS and CCP4 packages, has been developed to automate whole data-processing tasks in the case of multiple small-wedge data sets. Firstly, KAMO processes individual data sets and collates those indexed with equivalent unit-cell parameters. The space group is then chosen and any indexing ambiguity is resolved. Finally, clustering is performed, followed by merging with outlier rejections, and a report is subsequently created. Using synthetic and several real-world data sets collected from hundreds of crystals, it was demonstrated that merged structure-factor amplitudes can be obtained in a largely automated manner using KAMO, which greatly facilitated the structure analyses of challenging targets that only produced microcrystals. open access.
Neuropsychological and structural brain lesions in multiple sclerosis: a regional analysis.
Swirsky-Sacchetti, T; Mitchell, D R; Seward, J; Gonzales, C; Lublin, F; Knobler, R; Field, H L
1992-07-01
Quantified lesion scores derived from MRI correlate significantly with neuropsychological testing in patients with multiple sclerosis (MS). Variables used to reflect disease severity include total lesion area (TLA), ventricular-brain ratio, and size of the corpus callosum. We used these general measures of cerebral lesion involvement as well as specific ratings of lesion involvement by frontal, temporal, and parieto-occipital regions to quantify the topographic distribution of lesions and consequent effects upon cognitive function. Lesions were heavily distributed in the parieto-occipital regions bilaterally. Neuropsychological tests were highly related to all generalized measures of cerebral involvement, with TLA being the best predictor of neuropsychological deficit. Mean TLA for the cognitively impaired group was 28.30 cm2 versus 7.41 cm2 for the cognitively intact group (p less than 0.0001). Multiple regression analyses revealed that left frontal lobe involvement best predicted impaired abstract problem solving, memory, and word fluency. Left parieto-occipital lesion involvement best predicted deficits in verbal learning and complex visual-integrative skills. Analysis of regional cerebral lesion load may assist in understanding the particular pattern and course of cognitive deficits in MS.
Pan, Feng; Yang, Lizhi; Xiao, Wen
2017-09-04
In digital holographic microscopy (DHM), it is undesirable to observe coherent noise in the reconstructed images. The sources of the noise are mainly the parasitic interference fringes caused by multiple reflections and the speckle pattern caused by the optical scattering on the object surface. Here we propose a noise reduction approach in DHM by averaging multiple holograms recorded with a multimode laser. Based on the periodicity of the temporal coherence of a multimode semiconductor laser, we acquire a series of holograms by changing the optical path length difference between the reference beam and object beam. Because of the use of low coherence light, we can remove the parasitic interference fringes caused by multiple reflections in the holograms. In addition, the coherent noise patterns change in this process due to the different optical paths. Therefore, the coherent noise can be reduced by averaging the multiple reconstructions with uncorrelated noise patterns. Several experiments have been carried out to validate the effectiveness of the proposed approach for coherent noise reduction in DHM. It is shown a remarkable improvement both in amplitude imaging quality and phase measurement accuracy.
Long-Life Self-Renewing Solar Reflector Stack
Butler, Barry Lynn
1997-07-08
A long-life solar reflector includes a solar collector substrate and a base layer bonded to a solar collector substrate. The first layer includes a first reflective layer and a first acrylic or transparent polymer layer covering the first reflective layer to prevent exposure of the first reflective layer. The reflector also includes at least one upper layer removably bonded to the first acrylic or transparent polymer layer of the base layer. The upper layer includes a second reflective layer and a second acrylic or transparent polymer layer covering the second reflective layer to prevent exposure of the second reflective layer. The upper layer may be removed from the base reflective layer to expose the base layer, thereby lengthening the useful life of the solar reflector. A method of manufacturing a solar reflector includes the steps of bonding a base layer to a solar collector substrate, wherein the base reflective layer includes a first reflective layer and a first transparent polymer or acrylic layer covering the first reflective layer; and removably bonding a first upper layer to the first transparent polymer or acrylic layer of the base layer. The first upper layer includes a second reflective layer and a second transparent polymer or acrylic layer covering the second reflective layer to prevent exposure of the second reflective layer.
Note: Rigid holder to host and bend a crystal for multiple volume reflection of a particle beam
DOE Office of Scientific and Technical Information (OSTI.GOV)
Carassiti, V.; Melchiorri, M.; Dalpiaz, P.
2010-06-15
A holder to lodge and bend a silicon crystal to excite multivolume reflection of a high-energy particle beam has been designed and fabricated. A mechanically robust and stable structure fastens a crystal at best condition for experiments. The holder has allowed the observation of 12-time repeated volume reflection with very high efficiency. We detail the most important features behind the construction of the holder together with the characterization of the crystal being bent by the holder.
Therapist and supervisor competencies in cognitive behavioural therapy.
Prasko, Jan; Vyskocilová, Jana; Mozny, Petr; Novotny, Miroslav; Slepecky, Milos
2011-01-01
For cognitive behavioural therapy, acquisition and maintenance of psychotherapeutic and supervisory competencies is crucial. The PubMed, Web of Science and Scopus databases were searched for articles containing the following keywords: cognitive-behavioural therapy, competencies, therapeutic relationship, intervention, technique, training, supervision, self-reflection, empirically supported, transference, countertransference, scheme of therapy, dialectical behaviour therapy. The search was performed by repeating the words in different combinations with no language or time limitations. The articles were sorted and key articles listed in reference lists were searched. In addition, original texts by A.T. Beck, J. Beck, C. Padesky, M. Linehan, R. Leahy, J. Young, W. Kuyken and others were used. The resources were confronted with our own psychotherapeutic and supervisory experiences and only most relevant information was included in the text. Thus, the article is a review with conclusions concerned with competencies in cognitive behavioural therapy. For cognitive behavioural therapy, four domains of competencies in psychotherapy are crucial - relationship, case assessment and conceptualization, self-reflection and intervention. These may be divided into foundational, specific and supervisory. The foundational competencies include recognition of empirical basis for a clinical approach, good interpersonal skills, ability to establish and maintain the therapeutic relationship, self-reflection, sensitivity to a difference and ethical behaviour. The specific competencies involve the skill of case conceptualization in terms of maladaptive beliefs and patterns of behaviour, ability to think scientifically and teach this to the patient, structure therapy and sessions, assign and check homework, etc. The supervisor's competencies include multiple responsibilities in supporting the supervisee, identification and processing of the therapist's problems with the patient, continuous development, increasing the supervisee's self-reflection, serving as an example and being as effective as possible in the role of a clinical instructor. Both the literature and our own experiences underline the importance of competencies in cognitive behavioural therapy and supervision.
Potential damage to DC superconducting magnets due to the high frequency electromagnetic waves
NASA Technical Reports Server (NTRS)
Gabriel, G. J.
1977-01-01
Experimental data are presented in support of the hypothesis that a dc superconducting magnet coil does not behave strictly as an inductor, but as a complicated electrodynamic device capable of supporting electromagnetic waves. Travel times of nanosecond pulses and evidence of sinusoidal standing waves were observed on a prototype four-layer solenoidal coil at room temperature. Ringing observed during switching transients appears as a sequence of multiple reflected square pulses whose durations are related to the layer lengths. With sinusoidal excitation of the coil, the voltage amplitude between a pair of points on the coil exhibits maxima at those frequencies such that the distance between these points is an odd multiple of half wavelength in free space. Evidence indicates that any disturbance, such as that resulting from switching or sudden fault, initiates multiple reflections between layers, thus raising the possibility for sufficiently high voltages to cause breakdown.
Low, Diana H P; Motakis, Efthymios
2013-10-01
Binding free energy calculations obtained through molecular dynamics simulations reflect intermolecular interaction states through a series of independent snapshots. Typically, the free energies of multiple simulated series (each with slightly different starting conditions) need to be estimated. Previous approaches carry out this task by moving averages at certain decorrelation times, assuming that the system comes from a single conformation description of binding events. Here, we discuss a more general approach that uses statistical modeling, wavelets denoising and hierarchical clustering to estimate the significance of multiple statistically distinct subpopulations, reflecting potential macrostates of the system. We present the deltaGseg R package that performs macrostate estimation from multiple replicated series and allows molecular biologists/chemists to gain physical insight into the molecular details that are not easily accessible by experimental techniques. deltaGseg is a Bioconductor R package available at http://bioconductor.org/packages/release/bioc/html/deltaGseg.html.
Furze, Jennifer; Black, Lisa; Peck, Kirk; Jensen, Gail M
2011-08-01
Physical therapy educators are challenged to emphasize the importance of social responsibility as a vital curricular element of professional development. Through reflection, students are able to identify core values, beliefs, and attitudes as part of the professional development process. The purpose of this study was to explore student perceptions and values of a community engagement experience based upon frequency of participation. This qualitative research report investigated student perceptions of the community experience following participation. Data collection tools included an open-ended questionnaire and focus group interviews. Comparisons were made across data for participants who engaged in the activity one time versus multiple times. Data analysis revealed participation in the community engagement experience had a positive impact on most participants. One time only participants demonstrated increased self-awareness, contemplating change, and capacity to serve while more than one time participants described a deeper understanding of community, impact on others, and professional transformation. Student involvement in community engagement activities combined with structured reflection provided meaningful insight into participants' personal beliefs. The results suggest incorporation of community-based learning experiences into academic curriculum may be beneficial in the students' preliminary understanding of social responsibility.
Uncertainty analysis of depth predictions from seismic reflection data using Bayesian statistics
NASA Astrophysics Data System (ADS)
Michelioudakis, Dimitrios G.; Hobbs, Richard W.; Caiado, Camila C. S.
2018-03-01
Estimating the depths of target horizons from seismic reflection data is an important task in exploration geophysics. To constrain these depths we need a reliable and accurate velocity model. Here, we build an optimum 2D seismic reflection data processing flow focused on pre - stack deghosting filters and velocity model building and apply Bayesian methods, including Gaussian process emulation and Bayesian History Matching (BHM), to estimate the uncertainties of the depths of key horizons near the borehole DSDP-258 located in the Mentelle Basin, south west of Australia, and compare the results with the drilled core from that well. Following this strategy, the tie between the modelled and observed depths from DSDP-258 core was in accordance with the ± 2σ posterior credibility intervals and predictions for depths to key horizons were made for the two new drill sites, adjacent the existing borehole of the area. The probabilistic analysis allowed us to generate multiple realizations of pre-stack depth migrated images, these can be directly used to better constrain interpretation and identify potential risk at drill sites. The method will be applied to constrain the drilling targets for the upcoming International Ocean Discovery Program (IODP), leg 369.
Uncertainty analysis of depth predictions from seismic reflection data using Bayesian statistics
NASA Astrophysics Data System (ADS)
Michelioudakis, Dimitrios G.; Hobbs, Richard W.; Caiado, Camila C. S.
2018-06-01
Estimating the depths of target horizons from seismic reflection data is an important task in exploration geophysics. To constrain these depths we need a reliable and accurate velocity model. Here, we build an optimum 2-D seismic reflection data processing flow focused on pre-stack deghosting filters and velocity model building and apply Bayesian methods, including Gaussian process emulation and Bayesian History Matching, to estimate the uncertainties of the depths of key horizons near the Deep Sea Drilling Project (DSDP) borehole 258 (DSDP-258) located in the Mentelle Basin, southwest of Australia, and compare the results with the drilled core from that well. Following this strategy, the tie between the modelled and observed depths from DSDP-258 core was in accordance with the ±2σ posterior credibility intervals and predictions for depths to key horizons were made for the two new drill sites, adjacent to the existing borehole of the area. The probabilistic analysis allowed us to generate multiple realizations of pre-stack depth migrated images, these can be directly used to better constrain interpretation and identify potential risk at drill sites. The method will be applied to constrain the drilling targets for the upcoming International Ocean Discovery Program, leg 369.
Taylor, Bev; Roberts, Sue; Smyth, Therese; Tulloch, Moira
2015-10-01
To raise nurse managers' critical awareness of practice problems; uncover practice constraints and improve work effectiveness. Nurse management requires skills and knowledge, underscored by emotional intelligence. The research improved participants' practice and personal insights. Purposive sampling targeted nurse managers interested in improving their practice. Three experienced female nurse managers met fortnightly in a group, for 1 hour, for 10 meetings. The methods included: writing and sharing de-identified journal reflections; critically analysing practice stories; identifying a thematic concern; generating action strategies; and instituting and revising the action plan. Phase One resulted in the identification of the issue of 'being drained by the intensity of nurse managers' work'. The participants adopted five strategies: debriefing problematic situations; deflecting multiple requests; diffusing issues; naming dysfunctional behaviours; and regrouping. In Phase Two, participants implemented and revised the action plan strategies, which resulted in them feeling less drained by their work. Strategies can lessen nurse managers' sense of personal depletion. However, strategies cannot guarantee success every time because the emotional intelligence is integral to nurse management. Action research and reflection assist nurse managers to improve their practice and develop their emotional intelligence. © 2014 John Wiley & Sons Ltd.
Greene, Kathryn
2013-01-01
Adolescence is a time of increased risk taking, and recent intervention strategies have included adolescents planning or producing antirisk messages for their peers. Although these projects may generate enthusiasm, we know little about message planning or production as a strategy for changing adolescent decision-making and behavior. This article articulates the Theory of Active Involvement (TAI) to describe and explain the processes through which these active involvement interventions influence adolescents. TAI is based on social cognitive theory's notion of self-regulation and examines multiple perspective taking and activating the self-reflection processes. The theory specifically describes the process of cognitive changes experienced by participants in active involvement interventions. The sequence is conceptualized as starting when engagement with the intervention (arousal and involvement) produces skill and knowledge gains (immediate outcomes) that lead to reflection (perceived discrepancy) and then other cognitions (expectancies, norms, intentions), with the ultimate outcome being behavior change. Engaging the target audience in a process of self-reflection is conceptualized as the crucial ingredient for meaningful and sustainable change in cognitions and behavior. This article provides valuable insight into how active involvement strategies function and how to best design these interventions, particularly those targeting adolescents.
An Evaluation of the Influence of Case Method Instruction on the Reflective Thinking of MSW Students
ERIC Educational Resources Information Center
Milner, Marleen
2009-01-01
Social work practice requires that graduates be prepared to deal with complex, multifaceted problems which cannot be defined completely, do not have absolute, correct answers and can be approached from multiple perspectives. This study evaluated the influence of case-based instruction on MSW students' reflective judgment, an aspect of critical…
In the Middle of Something: Reflections on Multimodal Inquiry as Artful Bricolage
ERIC Educational Resources Information Center
Vasudevan, Lalitha; Reilly, Mary Ann
2013-01-01
This article presents a conversation about the nature of multimodal inquiry and composing between Lalitha Vasudevan and Mary Ann Reilly. The authors draw on their Twitter exchanges, blog posts, art, photography, and reflections as they consider what literacy education is and can be in a world that offers multiple means of expression. The…
Mirrors, Mirrors on the Wall...The Ubiquitous Multiple Reflection Error
ERIC Educational Resources Information Center
Lawson, Rebecca
2012-01-01
Participants decided when somebody, Janine, could see their face in a horizontal row of adjacent mirrors mounted flat on the same wall. They saw real mirrors and a shop-dummy representing Janine. Such coplanar mirrors reflect different, non-overlapping areas of a scene. However, almost everybody made an unexpected error: they claimed that Janine…
Video-Mediated Microteaching--A Stimulus for Reflection and Teacher Growth
ERIC Educational Resources Information Center
Kourieos, Stella
2016-01-01
Numerous studies have been conducted on the effectiveness of video as an effective means of reflective practice in pre-service Teacher Education. However, only few studies have explored preservice teachers' own perceptions in this regard in the field of ELT and none of these was related to primary level. To address this gap, multiple forms of…
NASA Astrophysics Data System (ADS)
Antikainen, Aku; Arteaga-Sierra, Francisco R.; Agrawal, Govind P.
2017-03-01
We show that temporal reflections off a moving refractive index barrier play a major role in the spectral broadening of a dual-wavelength input inside a highly nonlinear, dispersion-decreasing fiber. We also find that a recently developed linear theory of temporal reflections works well in predicting the reflected frequencies. Successive temporal reflections from multiple closely spaced solitons create a blueshifted spectral band, while continuous narrowing of solitons inside the dispersion-decreasing fiber enhances Raman-induced redshifts, leading to supercontinuum generation at relatively low pump powers. We also show how dispersive wave emission can be considered a special case of the more general process of temporal reflections. Hence our findings have implications on all systems able to support solitons.
Influence of aerosols, clouds, and sunglint on polarization spectra of Earthshine
NASA Astrophysics Data System (ADS)
Emde, Claudia; Buras-Schnell, Robert; Sterzik, Michael; Bagnulo, Stefano
2017-08-01
Context. Ground-based observations of the Earthshine, I.e., the light scattered by Earth to the Moon, and then reflected back to Earth, simulate space observations of our planet and represent a powerful benchmark for the studies of Earth-like planets. Earthshine spectra are strongly linearly polarized, owing to scattering by molecules and small particles in the atmosphere of the Earth and surface reflection, and may allow us to measure global atmospheric and surface properties of planet Earth. Aims: We aim to interpret already published spectropolarimetric observations of the Earthshine by comparing them with new radiative transfer model simulations including a fully realistic three-dimensional (3D) surface-atmosphere model for planet Earth. Methods: We used the highly advanced Monte Carlo radiative transfer model MYSTIC to simulate polarized radiative transfer in the atmosphere of the Earth without approximations regarding the geometry, taking into account the polarization from surface reflection and multiple scattering by molecules, aerosol particles, cloud droplets, and ice crystals. Results: We have shown that Earth spectropolarimetry is highly sensitive to all these input parameters, and we have presented simulations of a fully realistic Earth atmosphere-surface model including 3D cloud fields and two-dimensional (2D) surface property maps. Our modeling results show that scattering in high ice water clouds and reflection from the ocean surface are crucial to explain the continuum polarization at longer wavelengths as has been reported in Earthshine observations taken at the Very Large Telescope in 2011 (3.8% and 6.6% at 800 nm, depending on which part of Earth was visible from the Moon at the time of the observations). We found that the relatively high degree of polarization of 6.6% can be attributed to light reflected by the ocean surface in the sunglint region. High ice-water clouds reduce the amount of absorption in the O2A band and thus explain the weak O2A band feature in the observations.
Using MCNP6 to Estimate Fission Neutron Properties of a Reflected Plutonium Sphere
DOE Office of Scientific and Technical Information (OSTI.GOV)
Clark, Alexander Rich; Nelson, Mark Andrew; Hutchinson, Jesson D.
The purpose of this project was to determine the fission multiplicity distribution, p(v), for the Beryllium Reflected Plutonium (BeRP) ball and to determine whether or not it changed appreciably for various High Density Polyethylene (HDPE) reflected configurations. The motivation for this project was to determine whether or not the average number of neutrons emitted per fission, v, changed significantly enough to reduce the discrepancy between MCNP6 and Robba, Dowdy, Atwater (RDA) point kinetic model estimates of multiplication. The energy spectrum of neutrons that induced fissions in the BeRP ball, NIF (E), was also computed in order to determine the averagemore » energy of neutrons inducing fissions, NIF . p(v) was computed using the FMULT card, NIF (E) and NIF were computed using an F4 tally with an FM tally modifier (F4/FM) card, and the multiplication factor, k eff, was computed using the KCODE card. Although NIF (E) changed significantly between bare and HDPE reflected configurations of the BeRP ball, the change in p(v), and thus the change in v, was insignificant. This is likely due to a difference between the way that NIF is computed using the FMULT and F4/FM cards. The F4/FM card indicated that NIF (E) was essentially Watt-fission distributed for a bare configuration and highly thermalized for all HDPE reflected configurations, while the FMULT card returned an average energy between 1 and 2 MeV for all configurations, which would indicate that the spectrum is Watt-fission distributed, regardless of the amount of HDPE reflector. The spectrum computed with the F4/FM cards is more physically meaningful and so the discrepancy between it and the FMULT card result is being investigated. It is hoped that resolving the discrepancy between the FMULT and F4/FM card estimates of NIF(E) will provide better v estimates that will lead to RDA multiplication estimates that are in better agreement with MCNP6 simulations.« less
NASA Astrophysics Data System (ADS)
Huemmrich, K. F.; Middleton, E.; Corp, L. A.; Campbell, P. K.; Kustas, W. P.
2014-12-01
Optical sampling of spectral reflectance and solar induced fluorescence provide information on the physiological status of vegetation that can be used to infer stress responses and estimates of production. Multiple repeated observations are required to observe the effects of changing environmental conditions on vegetation. This study examines the use of optical signals to determine inputs to a light use efficiency (LUE) model describing productivity of a cornfield where repeated observations of carbon flux, spectral reflectance and fluorescence were collected. Data were collected at the Optimizing Production Inputs for Economic and Environmental Enhancement (OPE3) fields (39.03°N, 76.85°W) at USDA Beltsville Agricultural Research Center. Agricultural Research Service researchers measured CO2 fluxes using eddy covariance methods throughout the growing season. Optical measurements were made from the nearby tower supporting the NASA FUSION sensors. The sensor system consists of two dual channel, upward and downward looking, spectrometers used to simultaneously collect high spectral resolution measurements of reflected and fluoresced light from vegetation canopies. Estimates of chlorophyll fluorescence, combined with measures of vegetation pigment content and the Photosynthetic Reflectance Index (PRI) derived from the spectral reflectance are compared with CO2 fluxes over diurnal periods for multiple days. PRI detects changes in Xanthophyll cycle pigments using reflectance at 531 nm compared to a reference band at 570 nm. The relationships among the different optical measurements indicate that they are providing different types of information on the vegetation and that combinations of these measurements provide improved retrievals of CO2 fluxes than any index alone.
NASA Astrophysics Data System (ADS)
Huemmrich, K. F.; Corp, L.; Campbell, P. K.; Cook, B. D.; Middleton, E.; Cheng, Y.; Zhang, Q.; Russ, A.; Kustas, W. P.
2013-12-01
Optical sampling of spectral reflectance and solar induced fluorescence provide information on the physiological status of vegetation that can be used to infer stress responses and estimates of production. Multiple repeated observations can observe the effects of changing environmental conditions on vegetation. This study examines the use of optical signals to determine inputs to a light use efficiency (LUE) model describing productivity of a cornfield where repeated observations of carbon flux, spectral reflectance and fluorescence were collected. Data were collected at the Optimizing Production Inputs for Economic and Environmental Enhancement (OPE3) fields (39.03°N, 76.85°W) at USDA Beltsville Agricultural Research Center. Agricultural Research Service researchers measured CO2 fluxes using eddy covariance methods throughout the growing season. Optical measurements were made from the nearby tower supporting the NASA FUSION sensors. This sensor system consists of two dual channel, upward and downward looking, spectrometers used to simultaneously collect high spectral resolution measurements of reflected and fluoresced light from vegetation canopies. Estimates of chlorophyll fluorescence, combined with measures of vegetation pigment content and the Photosynthetic Reflectance Index (PRI) derived from the spectral reflectance are compared with CO2 fluxes over diurnal periods for multiple days. PRI detects changes in Xanthophyll cycle pigments using reflectance at 531 nm compared to a reference band at 570 nm. The relationships among the different optical measurements indicate that they are providing different types of information on the vegetation and that combinations of these measurements provide improved retrievals of CO2 fluxes than any index alone.
NASA Astrophysics Data System (ADS)
Bell, A.; Hioki, S.; Wang, Y.; Yang, P.; Di Girolamo, L.
2016-12-01
Previous studies found that including ice particle surface roughness in forward light scattering calculations significantly reduces the differences between observed and simulated polarimetric and radiometric observations. While it is suggested that some degree of roughness is desirable, the appropriate degree of surface roughness to be assumed in operational cloud property retrievals and the sensitivity of retrieval products to this assumption remains uncertain. In an effort to extricate this ambiguity, we will present a sensitivity analysis of space-borne multi-angle observations of reflectivity, to varying degrees of surface roughness. This process is two fold. First, sampling information and statistics of Multi-angle Imaging SpectroRadiometer (MISR) sensor data aboard the Terra platform, will be used to define the most coming viewing observation geometries. Using these defined geometries, reflectivity will be simulated for multiple degrees of roughness using results from adding-doubling radiative transfer simulations. Sensitivity of simulated reflectivity to surface roughness can then be quantified, thus yielding a more robust retrieval system. Secondly, sensitivity of the inverse problem will be analyzed. Spherical albedo values will be computed by feeding blocks of MISR data comprising cloudy pixels over ocean into the retrieval system, with assumed values of surface roughness. The sensitivity of spherical albedo to the inclusion of surface roughness can then be quantified, and the accuracy of retrieved parameters can be determined.
Identifying explosives using broadband millimeter-wave imaging
NASA Astrophysics Data System (ADS)
Weatherall, James C.; Yam, Kevin; Barber, Jeffrey; Smith, Barry T.; Smith, Peter R.; Greca, Joseph
2017-05-01
Millimeter wave imaging is employed in Advanced Technology Imaging (AIT) systems to screen personnel for concealed explosives and weapons. AIT systems deployed in airports auto-detect potential threats by highlighting their location on a generic outline of a person using imaging data collected over a range of frequency. We show how the spectral information from the imaging data can be used to identify the composition of an anomalous object, in particular if it is an explosive material. The discriminative value of the technique was illustrated on military sheet explosive using millimeter-wave reflection data at frequencies 18 - 40 GHz, and commercial explosives using 2 - 18 GHz, but the free-space measurement was limited to a single horn with a large-area sample. This work extends the method to imaging data collected at high resolution with a 18 - 40 GHz imaging system. The identification of explosives is accomplished by extracting the dielectric constant from the free-space, multifrequency data. The reflection coefficient is a function of frequency because of propagation effects associated with the material's complex dielectric constant, which include interference from multiple reflections and energy loss in the sample. The dielectric constant is obtained by numerically fitting the reflection coefficient as a function of frequency to an optical model. In principal, the implementation of this technique in standoff imaging systems would allow threat assessment to be accomplished within the scope of millimeter-wave screening.
Polarization Characteristics of Zebra Patterns in Type IV Solar Radio Bursts
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kaneda, K.; Misawa, H.; Tsuchiya, F.
The polarization characteristics of zebra patterns (ZPs) in type IV solar bursts were studied. We analyzed 21 ZP events observed by the Assembly of Metric-band Aperture Telescope and Real-time Analysis System between 2010 and 2015 and identified the following characteristics: a degree of circular polarization (DCP) in the range of 0%–70%, a temporal delay of 0–70 ms between the two circularly polarized components (i.e., the right- and left-handed components), and dominant ordinary-mode emission in about 81% of the events. For most events, the relation between the dominant and delayed components could be interpreted in the framework of fundamental plasma emissionmore » and depolarization during propagation, though the values of DCP and delay were distributed across wide ranges. Furthermore, it was found that the DCP and delay were positively correlated (rank correlation coefficient R = 0.62). As a possible interpretation of this relationship, we considered a model based on depolarization due to reflections at sharp density boundaries assuming fundamental plasma emission. The model calculations of depolarization including multiple reflections and group delay during propagation in the inhomogeneous corona showed that the DCP and delay decreased as the number of reflections increased, which is consistent with the observational results. The dispersive polarization characteristics could be explained by the different numbers of reflections causing depolarization.« less
Tracking iron in multiple sclerosis: a combined imaging and histopathological study at 7 Tesla
Hametner, Simon; Yao, Bing; van Gelderen, Peter; Merkle, Hellmut; Cantor, Fredric K.; Lassmann, Hans; Duyn, Jeff H.
2011-01-01
Previous authors have shown that the transverse relaxivity R2* and frequency shifts that characterize gradient echo signal decay in magnetic resonance imaging are closely associated with the distribution of iron and myelin in the brain's white matter. In multiple sclerosis, iron accumulation in brain tissue may reflect a multiplicity of pathological processes. Hence, iron may have the unique potential to serve as an in vivo magnetic resonance imaging tracer of disease pathology. To investigate the ability of iron in tracking multiple sclerosis-induced pathology by magnetic resonance imaging, we performed qualitative histopathological analysis of white matter lesions and normal-appearing white matter regions with variable appearance on gradient echo magnetic resonance imaging at 7 Tesla. The samples used for this study derive from two patients with multiple sclerosis and one non-multiple sclerosis donor. Magnetic resonance images were acquired using a whole body 7 Tesla magnetic resonance imaging scanner equipped with a 24-channel receive-only array designed for tissue imaging. A 3D multi-gradient echo sequence was obtained and quantitative R2* and phase maps were reconstructed. Immunohistochemical stainings for myelin and oligodendrocytes, microglia and macrophages, ferritin and ferritin light polypeptide were performed on 3- to 5-µm thick paraffin sections. Iron was detected with Perl's staining and 3,3′-diaminobenzidine-tetrahydrochloride enhanced Turnbull blue staining. In multiple sclerosis tissue, iron presence invariably matched with an increase in R2*. Conversely, R2* increase was not always associated with the presence of iron on histochemical staining. We interpret this finding as the effect of embedding, sectioning and staining procedures. These processes likely affected the histopathological analysis results but not the magnetic resonance imaging that was obtained before tissue manipulations. Several cellular sources of iron were identified. These sources included oligodendrocytes in normal-appearing white matter and activated macrophages/microglia at the edges of white matter lesions. Additionally, in white matter lesions, iron precipitation in aggregates typical of microbleeds was shown by the Perl's staining. Our combined imaging and pathological study shows that multi-gradient echo magnetic resonance imaging is a sensitive technique for the identification of iron in the brain tissue of patients with multiple sclerosis. However, magnetic resonance imaging-identified iron does not necessarily reflect pathology and may also be seen in apparently normal tissue. Iron identification by multi-gradient echo magnetic resonance imaging in diseased tissues can shed light on the pathological processes when coupled with topographical information and patient disease history. PMID:22171355
Multiple energy synchrotron biomedical imaging system
NASA Astrophysics Data System (ADS)
Bassey, B.; Martinson, M.; Samadi, N.; Belev, G.; Karanfil, C.; Qi, P.; Chapman, D.
2016-12-01
A multiple energy imaging system that can extract multiple endogenous or induced contrast materials as well as water and bone images would be ideal for imaging of biological subjects. The continuous spectrum available from synchrotron light facilities provides a nearly perfect source for multiple energy x-ray imaging. A novel multiple energy x-ray imaging system, which prepares a horizontally focused polychromatic x-ray beam, has been developed at the BioMedical Imaging and Therapy bend magnet beamline at the Canadian Light Source. The imaging system is made up of a cylindrically bent Laue single silicon (5,1,1) crystal monochromator, scanning and positioning stages for the subjects, flat panel (area) detector, and a data acquisition and control system. Depending on the crystal’s bent radius, reflection type, and the horizontal beam width of the filtered synchrotron radiation (20-50 keV) used, the size and spectral energy range of the focused beam prepared varied. For example, with a bent radius of 95 cm, a (1,1,1) type reflection and a 50 mm wide beam, a 0.5 mm wide focused beam of spectral energy range 27 keV-43 keV was obtained. This spectral energy range covers the K-edges of iodine (33.17 keV), xenon (34.56 keV), cesium (35.99 keV), and barium (37.44 keV) some of these elements are used as biomedical and clinical contrast agents. Using the developed imaging system, a test subject composed of iodine, xenon, cesium, and barium along with water and bone were imaged and their projected concentrations successfully extracted. The estimated dose rate to test subjects imaged at a ring current of 200 mA is 8.7 mGy s-1, corresponding to a cumulative dose of 1.3 Gy and a dose of 26.1 mGy per image. Potential biomedical applications of the imaging system will include projection imaging that requires any of the extracted elements as a contrast agent and multi-contrast K-edge imaging.
Cramer, Stig P; Modvig, Signe; Simonsen, Helle J; Frederiksen, Jette L; Larsson, Henrik B W
2015-09-01
Optic neuritis is an acute inflammatory condition that is highly associated with multiple sclerosis. Currently, the best predictor of future development of multiple sclerosis is the number of T2 lesions visualized by magnetic resonance imaging. Previous research has found abnormalities in the permeability of the blood-brain barrier in normal-appearing white matter of patients with multiple sclerosis and here, for the first time, we present a study on the capability of blood-brain barrier permeability in predicting conversion from optic neuritis to multiple sclerosis and a direct comparison with cerebrospinal fluid markers of inflammation, cellular trafficking and blood-brain barrier breakdown. To this end, we applied dynamic contrast-enhanced magnetic resonance imaging at 3 T to measure blood-brain barrier permeability in 39 patients with monosymptomatic optic neuritis, all referred for imaging as part of the diagnostic work-up at time of diagnosis. Eighteen healthy controls were included for comparison. Patients had magnetic resonance imaging and lumbar puncture performed within 4 weeks of onset of optic neuritis. Information on multiple sclerosis conversion was acquired from hospital records 2 years after optic neuritis onset. Logistic regression analysis showed that baseline permeability in normal-appearing white matter significantly improved prediction of multiple sclerosis conversion (according to the 2010 revised McDonald diagnostic criteria) within 2 years compared to T2 lesion count alone. There was no correlation between permeability and T2 lesion count. An increase in permeability in normal-appearing white matter of 0.1 ml/100 g/min increased the risk of multiple sclerosis 8.5 times whereas having more than nine T2 lesions increased the risk 52.6 times. Receiver operating characteristic curve analysis of permeability in normal-appearing white matter gave a cut-off of 0.13 ml/100 g/min, which predicted conversion to multiple sclerosis with a sensitivity of 88% and specificity of 72%. We found a significant correlation between permeability and the leucocyte count in cerebrospinal fluid as well as levels of CXCL10 and MMP9 in the cerebrospinal fluid. These findings suggest that blood-brain barrier permeability, as measured by magnetic resonance imaging, may provide novel pathological information as a marker of neuroinflammation related to multiple sclerosis, to some extent reflecting cellular permeability of the blood-brain barrier, whereas T2 lesion count may more reflect the length of the subclinical pre-relapse phase.See Naismith and Cross (doi:10.1093/brain/awv196) for a scientific commentary on this article. © The Author (2015). Published by Oxford University Press on behalf of the Guarantors of Brain.
NASA Astrophysics Data System (ADS)
Lappa, Marcello; Drikakis, Dimitris; Kokkinakis, Ioannis
2017-03-01
This paper concerns the propagation of shock waves in an enclosure filled with dusty gas. The main motivation for this problem is to probe the effect on such dynamics of solid particles dispersed in the fluid medium. This subject, which has attracted so much attention over recent years given its important implications in the study of the structural stability of systems exposed to high-energy internal detonations, is approached here in the framework of a hybrid numerical two-way coupled Eulerian-Lagrangian methodology. In particular, insights are sought by considering a relatively simple archetypal setting corresponding to a shock wave originating from a small spherical region initialized on the basis of available analytic solutions. The response of the system is explored numerically with respect to several parameters, including the blast intensity (via the related value of the initial shock Mach number), the solid mass fraction (mass load), and the particle size (Stokes number). Results are presented in terms of pressure-load diagrams. Beyond practical applications, it is shown that a kaleidoscope of fascinating patterns is produced by the "triadic" relationships among multiple shock reflection events and particle-fluid and particle-wall interaction dynamics. These would be of great interest to researchers and scientists interested in fundamental problems relating to the general theory of pattern formation in complex nonlinear multiphase systems.
Multiple Chemical Sensitivity (MCS) - Scientific and Public-Health Aspects
Schwenk, Michael
2004-01-01
Multiple Chemical Sensitivity (MCS) is a phenomenon which the ENT-doctor should be familiar with. It has its roots in the description of a syndrome in 1987. A worker spilled chemicals at his workplace and from then on he reacted highly sensitive to chemicals. Today, there are many people who explain their complaints with self-suspected MCS. Various pathopysiological models have been proposed, including toxicological, immunological or behaviorial models. But no-one could be proved so far. Since controlled provocation tests have also provided unclear results, an increasing number of doctors assumes today, that MCS reflects a psychic condition. In 1996, an expert team of the WHO has suggested the renaming of MCS to "idiopathic environmental illness" (IEI). However, other doctors still assume a chemical cause. Since there are neither straightforward diagnostic methods to proof MCS, nor reliable therapeutic concepts, treatment of MCS-patients is usually difficult. The MCS-debate (somatic vs psychic causes) seems to reflect the dilemma of the medical profession today, that somatic disorders of known origin can be well treated, whereas the increasing number of psychosomatic/ somatoform disorders is often resistant to medical help. The ENT-doctor should pay attention to changes of the nasal mucous membrane, nasal resistance and the sense of smell. Moreover he should know about the peculiarities of MCS-patients. The manuscript describes the present knowledge and state of discussion with special regard to the situation in Germany. PMID:22073047
Disturbance patterns in a socio-ecological system at multiple scales
G. Zurlini; Kurt H. Riitters; N. Zaccarelli; I. Petrosillo; K.B. Jones; L. Rossi
2006-01-01
Ecological systems with hierarchical organization and non-equilibrium dynamics require multiple-scale analyses to comprehend how a system is structured and to formulate hypotheses about regulatory mechanisms. Characteristic scales in real landscapes are determined by, or at least reflect, the spatial patterns and scales of constraining human interactions with the...
Three-dimensional analytical solutions of the atmospheric diffusion equation with multiple sources and height-dependent wind speed and eddy diffusivities are derived in a systematic fashion. For homogeneous Neumann (total reflection), Dirichlet (total adsorpti...
Three-dimensional analytical solutions of the atmospheric diffusion equation with multiple sources and height-dependent wind speed and eddy diffusivities are derived in a systematic fashion. For homogeneous Neumann (total reflection), Dirichlet (total adsorpti...
Training in dissemination and implementation research: a field-wide perspective.
Proctor, Enola K; Chambers, David A
2017-09-01
We report outcomes of an NIH-convened meeting on training for dissemination and implementation (D&I) research, focused on accelerating translation of research to healthcare practice. Participants included leaders of current trainings, center directors, and those trained in existing programs. Given the large proportion of D&I research focused on cancer control, mental health, and substance abuse, participants overwhelmingly reflected the experiences and challenges of gaining capacity in behavioral health-related D&I research. The 2-day meeting required participants to draw upon their experiences to help build a field-wide perspective for D&I research training, identify resources needed to support this perspective, and brainstorm gaps in training that needed to be filled. Questions were sent to participants in advance, and responses were synthesized and presented to discuss during the meeting. A preliminary "field-wide" perspective emerged, spanning multiple disciplines, training models, and career levels. Current programs face high demand, need for continued evolution to reflect field advances, and sustainability challenges. Current gaps include implementation practice and predoctoral training. Federal funding is key to D&I research training, be it through grants or agency-led training programs, in order to span and address specialized disease and disorder foci and career tracks.
NASA Astrophysics Data System (ADS)
Jackson-Booth, N.
2016-12-01
Artificial Ionospheric Modification (AIM) attempts to modify the ionosphere in order to alter the propagation environment. It can be achieved through injecting the ionosphere with aerosols, chemicals or radio signals. The effects of any such release can be detected through the deployment of sensors, including ground based high frequency (HF) sounders. During the Metal Oxide Space Clouds (MOSC) experiment (undertaken in April/May 2013 in the Kwajalein Atoll, part of the Marshall Islands) several oblique ionograms were recorded from a ground based HF system. These ionograms were collected over multiple geometries and allowed the effects on the HF propagation environment to be understood. These ionograms have subsequently been used in the ClOud Reflection Algorithm (CORA) to attempt to model the evolution of the cloud following release. This paper describes the latest validation results from CORA, both from testing against ionograms, but also other independent models of cloud evolution from MOSC. For all testing the various cloud models (including that generated by CORA) were incorporated into a background ionosphere through which a 3D numerical ray trace was run to produce synthetic ionograms that could be compared with the ionograms recorded during MOSC.
Extreme ultraviolet lithography machine
Tichenor, Daniel A.; Kubiak, Glenn D.; Haney, Steven J.; Sweeney, Donald W.
2000-01-01
An extreme ultraviolet lithography (EUVL) machine or system for producing integrated circuit (IC) components, such as transistors, formed on a substrate. The EUVL machine utilizes a laser plasma point source directed via an optical arrangement onto a mask or reticle which is reflected by a multiple mirror system onto the substrate or target. The EUVL machine operates in the 10-14 nm wavelength soft x-ray photon. Basically the EUV machine includes an evacuated source chamber, an evacuated main or project chamber interconnected by a transport tube arrangement, wherein a laser beam is directed into a plasma generator which produces an illumination beam which is directed by optics from the source chamber through the connecting tube, into the projection chamber, and onto the reticle or mask, from which a patterned beam is reflected by optics in a projection optics (PO) box mounted in the main or projection chamber onto the substrate. In one embodiment of a EUVL machine, nine optical components are utilized, with four of the optical components located in the PO box. The main or projection chamber includes vibration isolators for the PO box and a vibration isolator mounting for the substrate, with the main or projection chamber being mounted on a support structure and being isolated.
NASA Astrophysics Data System (ADS)
Breitzke, Monika; Bohlen, Thomas
2010-05-01
Modelling sound propagation in the ocean is an essential tool to assess the potential risk of air-gun shots on marine mammals. Based on a 2.5-D finite-difference code a full waveform modelling approach is presented, which determines both sound exposure levels of single shots and cumulative sound exposure levels of multiple shots fired along a seismic line. Band-limited point source approximations of compact air-gun clusters deployed by R/V Polarstern in polar regions are used as sound sources. Marine mammals are simulated as static receivers. Applications to deep and shallow water models including constant and depth-dependent sound velocity profiles of the Southern Ocean show dipole-like directivities in case of single shots and tubular cumulative sound exposure level fields beneath the seismic line in case of multiple shots. Compared to a semi-infinite model an incorporation of seafloor reflections enhances the seismically induced noise levels close to the sea surface. Refraction due to sound velocity gradients and sound channelling in near-surface ducts are evident, but affect only low to moderate levels. Hence, exposure zone radii derived for different hearing thresholds are almost independent of the sound velocity structure. With decreasing thresholds radii increase according to a spherical 20 log10 r law in case of single shots and according to a cylindrical 10 log10 r law in case of multiple shots. A doubling of the shot interval diminishes the cumulative sound exposure levels by -3 dB and halves the radii. The ocean bottom properties only slightly affect the radii in shallow waters, if the normal incidence reflection coefficient exceeds 0.2.
Hybrid colored noise process with space-dependent switching rates
NASA Astrophysics Data System (ADS)
Bressloff, Paul C.; Lawley, Sean D.
2017-07-01
A fundamental issue in the theory of continuous stochastic process is the interpretation of multiplicative white noise, which is often referred to as the Itô-Stratonovich dilemma. From a physical perspective, this reflects the need to introduce additional constraints in order to specify the nature of the noise, whereas from a mathematical perspective it reflects an ambiguity in the formulation of stochastic differential equations (SDEs). Recently, we have identified a mechanism for obtaining an Itô SDE based on a form of temporal disorder. Motivated by switching processes in molecular biology, we considered a Brownian particle that randomly switches between two distinct conformational states with different diffusivities. In each state, the particle undergoes normal diffusion (additive noise) so there is no ambiguity in the interpretation of the noise. However, if the switching rates depend on position, then in the fast switching limit one obtains Brownian motion with a space-dependent diffusivity of the Itô form. In this paper, we extend our theory to include colored additive noise. We show that the nature of the effective multiplicative noise process obtained by taking both the white-noise limit (κ →0 ) and fast switching limit (ɛ →0 ) depends on the order the two limits are taken. If the white-noise limit is taken first, then we obtain Itô, and if the fast switching limit is taken first, then we obtain Stratonovich. Moreover, the form of the effective diffusion coefficient differs in the two cases. The latter result holds even in the case of space-independent transition rates, where one obtains additive noise processes with different diffusion coefficients. Finally, we show that yet another form of multiplicative noise is obtained in the simultaneous limit ɛ ,κ →0 with ɛ /κ2 fixed.
Exploring Mercury's Surface in UltraViolet from Orbit
NASA Astrophysics Data System (ADS)
Izenberg, N.
2017-12-01
The MESSENGER Mission's Ultraviolet and Visible Spectrometer (UVVS) component of its Mercury Atmosphere and Surface Composition Spectrometer (MASCS) instrument obtained approximately 4600 point observations of Mercury's surface in middle ultraviolet (MUV; 210 nm - 300 nm) and far ultraviolet (FUV; 119.1 - 122.5 nm and 129.2 - 131.5 nm) wavelengths over the course of its orbital mission, mostly in Mercury's southern hemisphere. Given the very low (<1 to 2 wt %) average abundance of iron in the silicates of Mercury observed by multiple MESSENGER instruments, the near- to middle-ultraviolet wavelengths encompassing the oxygen metal charge transfer band (<400 nm), which is more sensitive to the presence of iron than the classic 1 micron absorption band, provides potentially useful additional compositional insight into the top layer of Mercury's regolith. The presence of nano- and microphase carbon also has potentially significant expression in the ultraviolet, and the interplay and variation between carbon and iron in mercury surface materials is an active area of investigation. Analysis of middle-UV surface reflectance and parameters appear to support the presence of varying amounts of carbon in different spectral or geologic units on Mercury. Far-UV reflectance data is currently under-utilized, but analysis of lunar surface by the Lunar Reconnaissance Orbiter (LRO) Lyman Alpha Mapping Project (LAMP) indicate that the data are sensitive to both composition and space weathering. The far-UV reflectance from MASCS may provide similar information for the Mercury surface, complementing results from longer wavelengths. MESSENGER data products for surface reflectance include middle-UV reflectance spectra, ultraviolet far-UV reflectance values, combined middle-UV through near-infrared spectra (210 nm - 1450 nm), a global `spectral cube' of near-UV to near-IR, and an upcoming UV spectral cube.
Upper crust beneath the central Illinois basin, United States
McBride, J.H.; Kolata, Dennis R.
1999-01-01
Newly available industry seismic reflection data provide critical information for understanding the structure and origin of the upper crust (0-12 km depth) beneath the central Illinois basin and the seismic-tectonic framework north of the New Madrid seismic zone in the central Mississippi Valley. Mapping of reflector sequences furnishes the first broad three-dimensional perspective of the structure of Precambrian basement beneath the central United States Midcontinent. The highly coherent basement reflectivity is expressed as a synformal wedge of dipping and subhorizontal reflections situated beneath the center of the Illinois basin that thickens and deepens to the northeast (e.g., 0 to ???5.3 km thickness along a 123 km south to north line). The thickening trend of the wedge qualitatively mimics the northward thickening of the Late Cambrian Mt. Simon Sandstone; however, other Paleozoic units in the Illinois basin generally thicken southward into the basin center. The seismic data also reveal an anomalous subsequence defined by a spoon-shaped distribution of disrupted reflections located along the southern margin of the wedge. The boundaries of this subsequence are marked by distinct steeply dipping reflections (possible thrust faults?) that continue or project up to antiformal disruptions of lower Paleozoic marker reflectors, suggesting Paleozoic or possibly later tectonic reactivation of Precambrian structure. The areal extent of the subsequence appears to roughly correspond to an anomalous concentration of larger magnitude upper to middle crustal earthquakes. There are multiple hypotheses for the origin of the Precambrian reflectivity, including basaltic flows or sills interlayered with clastic sediments and/or emplaced within felsic igneous rocks. Such explanations are analogous to nearby Keweenawan rift-related volcanism and sedimentation, which initiated during Proterozoic rifting, and were followed eventually by reverse faulting along the rift margins caused by Grenville compression.
NASA Technical Reports Server (NTRS)
Valdez, P. F.; Donohoe, G. W.
1997-01-01
Statistical classification of remotely sensed images attempts to discriminate between surface cover types on the basis of the spectral response recorded by a sensor. It is well known that surfaces reflect incident radiation as a function of wavelength producing a spectral signature specific to the material under investigation. Multispectral and hyperspectral sensors sample the spectral response over tens and even hundreds of wavelength bands to capture the variation of spectral response with wavelength. Classification algorithms then exploit these differences in spectral response to distinguish between materials of interest. Sensors of this type, however, collect detailed spectral information from one direction (usually nadir); consequently, do not consider the directional nature of reflectance potentially detectable at different sensor view angles. Improvements in sensor technology have resulted in remote sensing platforms capable of detecting reflected energy across wavelengths (spectral signatures) and from multiple view angles (angular signatures) in the fore and aft directions. Sensors of this type include: the moderate resolution imaging spectroradiometer (MODIS), the multiangle imaging spectroradiometer (MISR), and the airborne solid-state array spectroradiometer (ASAS). A goal of this paper, then, is to explore the utility of Bidirectional Reflectance Distribution Function (BRDF) models in the selection of optimal view angles for the classification of remotely sensed images by employing a strategy of searching for the maximum difference between surface BRDFs. After a brief discussion of directional reflect ante in Section 2, attention is directed to the Beard-Maxwell BRDF model and its use in predicting the bidirectional reflectance of a surface. The selection of optimal viewing angles is addressed in Section 3, followed by conclusions and future work in Section 4.
Simulation and Implementation of Moth-eye Structures as a Broadband Anti-Reflective Layer
NASA Astrophysics Data System (ADS)
Deshpande, Ketan S.
Conventional single layer thin anti-reflective coatings (ARCs) are only suitable for narrowband applications. A multilayer film stack is often employed for broadband applications. A coating of multiple layers with alternating low and high refractive index materials increases the overall cost of the system. This makes multilayer ARCs unsuitable for low-cost broadband applications. Since the discovery of moth-eye corneal nipple patterns and their potential applicability in the field of broadband ARCs, many studies have been carried out to fabricate these bio-inspired nanostructures with available manufacturing processes. Plasma etching processes used in microelectronic manufacturing are applied for creating these nanostructures at the Rochester Institute of Technology's Semiconductor & Microsystems Fabrication Laboratory (SMFL). Atomic Force Microscope (AFM) scanned surfaces of the nanostructure layer are simulated and characterized for their optical properties using a Finite-Difference Time Domain (FDTD) simulator from Lumerical Solutions, Inc. known as FDTD Solutions. Simulation results show that the layer is anti-reflective over 50 to 350 nm broadband of wavelengths at 0° angle of incidence. These simulation results were supported by ellipsometer reflection measurements off the actual samples at multiple angles of light incidence, which show a 10% to 15% decrease in reflection for 240 to 400 nm wavelengths. Further improvements in the optical efficiency of these structures can be achieved through simulation-fabrication-characterization cycles performed for this project. The optimized nanostructures can then serve the purpose of low-cost anti-reflective coatings for solar cells and similar applications.
NASA Astrophysics Data System (ADS)
Zhao, Chun-yan; Li, Xin; Wei, Wei; Zheng, Xiao-bing
2016-10-01
With the progress of quantitative remote sensing, the acquisition of surface BRDF becomes more and more important. In order to improve the accuracy of the surface BRDF measurements, a VNIR-SWIR Bidirectional Reflectance Automatic Measurement System, which was developed by Hefei Institutes of Physical Science (HIPS), is introduced that allows in situ measurements of hyperspectral bidirectional reflectance data. Hyperspectral bidirectional reflectance distribution function data sets taken with the BRDF automatic measurement system nominally cover the spectral range between 390 and 2390 nm in 971 bands. In July 2007, September 2008, June 2011, we acquired a series of the BRDF data covered Dunhuang radiometric calibration test site in terms of the BRDF measurement system. We have not obtained such comprehensive and accurate data as they are, since 1990s when the site was built up. These data are applied to calibration for FY-2 and other satellites sensors. Field BRDF data of a Dunhuang site surface reveal a strong spectral variability. An anisotropy factor (ANIF), defined as the ratio between the directional reflectance and nadir reflectance over the hemisphere, is introduced as a surrogate measurement for the extent of spectral BRDF effects. The ANIF data show a very high correlation with the solar zenith angle due to multiple scattering effects over a desert site. Since surface geometry, multiple scattering, and BRDF effects are related, these findings may help to derive BRDF model parameters from the in-situ BRDF measurement remotely sensed hyperspectral data sets.
Krouse, Robert S; Grant, Marcia; Wendel, Christopher S; Mohler, M Jane; Rawl, Susan M; Baldwin, Carol M; Coons, Stephen Joel; McCorkle, Ruth; Ko, Clifford Y; Schmidt, C Max
2007-12-01
Intestinal stomas have a major impact on Cases' lives. It is essential to better understand the areas in which interventions may help to minimize the negative consequences. This was a case-control survey study using validated instruments (City of Hope Quality of Life-Ostomy and Short Form 36 for Veterans). Cases were accrued from Veterans Affairs Medical Centers in Tucson, Indianapolis, and Los Angeles. Eligibility included a major intra-abdominal surgical procedure that led to an ostomy (cases), or a similar procedure that did not mandate a stoma (controls). Analysis included quantitative and qualitative responses. The response rate was 48 percent (511/1,063). Cases and controls had relatively similar demographic characteristics. Because of low numbers of female respondents (13 cases and 11 controls), only results for males are reported. Based on both the City of Hope Quality of Life-Ostomy and Short Form 36 for Veterans, cases reported significantly poorer scores on scales/domains reflecting psychologic and social functioning and well being. Additionally, cases reported poorer scores on Short Form 36 for Veterans scales reflecting physical functioning and significantly lower scores on multiple items in the social domain of the City of Hope Quality of Life-Ostomy compared with controls. Two-thirds of cases replied to an open-ended question on their "greatest challenge" related to their ostomy, which led to further clarification of major issues. Multiple health-related quality of life problems were reported by male veterans with intestinal stomas. The greatest differences between cases and controls were observed in the social and psychologic domains/scales. Findings from this study provide a greater understanding of the challenges faced by ostomates and will inform the development and evaluation of urgently needed intervention strategies.
2014-01-01
Background Network meta-analysis (NMA) enables simultaneous comparison of multiple treatments while preserving randomisation. When summarising evidence to inform an economic evaluation, it is important that the analysis accurately reflects the dependency structure within the data, as correlations between outcomes may have implication for estimating the net benefit associated with treatment. A multivariate NMA offers a framework for evaluating multiple treatments across multiple outcome measures while accounting for the correlation structure between outcomes. Methods The standard NMA model is extended to multiple outcome settings in two stages. In the first stage, information is borrowed across outcomes as well across studies through modelling the within-study and between-study correlation structure. In the second stage, we make use of the additional assumption that intervention effects are exchangeable between outcomes to predict effect estimates for all outcomes, including effect estimates on outcomes where evidence is either sparse or the treatment had not been considered by any one of the studies included in the analysis. We apply the methods to binary outcome data from a systematic review evaluating the effectiveness of nine home safety interventions on uptake of three poisoning prevention practices (safe storage of medicines, safe storage of other household products, and possession of poison centre control telephone number) in households with children. Analyses are conducted in WinBUGS using Markov Chain Monte Carlo (MCMC) simulations. Results Univariate and the first stage multivariate models produced broadly similar point estimates of intervention effects but the uncertainty around the multivariate estimates varied depending on the prior distribution specified for the between-study covariance structure. The second stage multivariate analyses produced more precise effect estimates while enabling intervention effects to be predicted for all outcomes, including intervention effects on outcomes not directly considered by the studies included in the analysis. Conclusions Accounting for the dependency between outcomes in a multivariate meta-analysis may or may not improve the precision of effect estimates from a network meta-analysis compared to analysing each outcome separately. PMID:25047164
Enhancement of Photon Number Reflected by the Relativistic Flying Mirror
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kando, M.; Pirozhkov, A. S.; Kawase, K.
2009-12-04
Laser light reflection by a relativistically moving electron density modulation (flying mirror) in a wake wave generated in a plasma by a high intensity laser pulse is investigated experimentally. A counterpropagating laser pulse is reflected and upshifted in frequency with a multiplication factor of 37-66, corresponding to the extreme ultraviolet wavelength. The demonstrated flying mirror reflectivity (from 3x10{sup -6} to 2x10{sup -5}, and from 1.3x10{sup -4} to 0.6x10{sup -3}, for the photon number and pulse energy, respectively) is close to the theoretical estimate for the parameters of the experiment.
NASA Technical Reports Server (NTRS)
Tai, Hsiang
2006-01-01
In a typical optic fiber Bragg grating (FBG) strain measurement, unless in an ideal static laboratory environment, the presence of vibration or often disturbance always exists, which often creates spurious multiple peaks in the reflected spectrum, resulting in a non-unique determination of strain value. In this report we attempt to investigate the origin of this phenomenon by physical arguments and simple numerical simulation. We postulate that the fiber gratings execute small amplitude transverse vibrations changing the optical path in which the reflected light traverses slightly and non-uniformly. Ultimately, this causes the multi-peak reflected spectrum.
Variable area light reflecting assembly
Howard, T.C.
1986-12-23
Device is described for tracking daylight and projecting it into a building. The device tracks the sun and automatically adjusts both the orientation and area of the reflecting surface. The device may be mounted in either a wall or roof of a building. Additionally, multiple devices may be employed in a light shaft in a building, providing daylight to several different floors. The preferred embodiment employs a thin reflective film as the reflecting device. One edge of the reflective film is fixed, and the opposite end is attached to a spring-loaded take-up roller. As the sun moves across the sky, the take-up roller automatically adjusts the angle and surface area of the film. Additionally, louvers may be mounted at the light entrance to the device to reflect incoming daylight in an angle perpendicular to the device to provide maximum reflective capability when daylight enters the device at non-perpendicular angles. 9 figs.
Variable area light reflecting assembly
Howard, Thomas C.
1986-01-01
Device for tracking daylight and projecting it into a building. The device tracks the sun and automatically adjusts both the orientation and area of the reflecting surface. The device may be mounted in either a wall or roof of a building. Additionally, multiple devices may be employed in a light shaft in a building, providing daylight to several different floors. The preferred embodiment employs a thin reflective film as the reflecting device. One edge of the reflective film is fixed, and the opposite end is attached to a spring-loaded take-up roller. As the sun moves across the sky, the take-up roller automatically adjusts the angle and surface area of the film. Additionally, louvers may be mounted at the light entrance to the device to reflect incoming daylight in an angle perpendicular to the device to provide maximum reflective capability when daylight enters the device at non-perpendicular angles.
Hemispherical reflectance model for passive images in an outdoor environment.
Kim, Charles C; Thai, Bea; Yamaoka, Neil; Aboutalib, Omar
2015-05-01
We present a hemispherical reflectance model for simulating passive images in an outdoor environment where illumination is provided by natural sources such as the sun and the clouds. While the bidirectional reflectance distribution function (BRDF) accurately produces radiance from any objects after the illumination, using the BRDF in calculating radiance requires double integration. Replacing the BRDF by hemispherical reflectance under the natural sources transforms the double integration into a multiplication. This reduces both storage space and computation time. We present the formalism for the radiance of the scene using hemispherical reflectance instead of BRDF. This enables us to generate passive images in an outdoor environment taking advantage of the computational and storage efficiencies. We show some examples for illustration.
Stiers, Peter; Goulas, Alexandros
2018-06-01
A subset of regions in the lateral and medial prefrontal cortex and the anterior insula increase their activity level whenever a cognitive task becomes more demanding, regardless of the specific nature of this demand. During execution of a task, these areas and the surrounding cortex temporally encode aspects of the task context in spatially distributed patterns of activity. It is not clear whether these patterns reflect underlying anatomical subnetworks that still exist when task execution has finished. We use fMRI in 12 participants performing alternating blocks of three cognitive tasks to address this question. A first data set is used to define multiple demand regions in each participant. A second dataset from the same participants is used to determine multiple demand voxel assemblies with a preference for one task over the others. We then show that these voxels remain functionally coupled during execution of non-preferred tasks and that they exhibit stronger functional connectivity during rest. This indicates that the assemblies of task preference sharing voxels reflect patterns of underlying anatomical connections. Moreover, we show that voxels preferring the same task have more similar whole brain functional connectivity profiles that are consistent across participants. This suggests that voxel assemblies differ in patterns of input-output connections, most likely reflecting task demand-specific information exchange.
Shera, Christopher A; Cooper, Nigel P
2013-04-01
At low stimulus levels, basilar-membrane (BM) mechanical transfer functions in sensitive cochleae manifest a quasiperiodic rippling pattern in both amplitude and phase. Analysis of the responses of active cochlear models suggests that the rippling is a mechanical interference pattern created by multiple internal reflection within the cochlea. In models, the interference arises when reverse-traveling waves responsible for stimulus-frequency otoacoustic emissions (SFOAEs) reflect off the stapes on their way to the ear canal, launching a secondary forward-traveling wave that combines with the primary wave produced by the stimulus. Frequency-dependent phase differences between the two waves then create the rippling pattern measurable on the BM. Measurements of BM ripples and SFOAEs in individual chinchilla ears demonstrate that the ripples are strongly correlated with the acoustic interference pattern measured in ear-canal pressure, consistent with a common origin involving the generation of SFOAEs. In BM responses to clicks, the ripples appear as temporal fine structure in the response envelope (multiple lobes, waxing and waning). Analysis of the ripple spacing and response phase gradients provides a test for the role of fast- and slow-wave modes of reverse energy propagation within the cochlea. The data indicate that SFOAE delays are consistent with reverse slow-wave propagation but much too long to be explained by fast waves.
Assessing the Application of Cloud-Shadow Atmospheric Correction Algorithm on HICO
2014-05-01
multiple times and intercompare the results to assess variability in the retrieved reflectance spectra. Retrieved chlorophyll values from this...intercomparison are similar and also agree well with the In situ chlorophyll measurements. 15. SUBJECT TERMS Atmospheric correction, cloud-shadow...reflectance spectra. Re- trieved chlorophyll values from this intercomparison are similar and also agree well with the in situ chlorophyll measurements
The Effect of Reflective Portfolio Use on Student Self-Regulation Skills in Science
ERIC Educational Resources Information Center
Greenwood, Jacob C.
2010-01-01
This study investigated the use of reflective portfolios in science as a means to provide students a medium to develop a repertoire of study and self-regulation strategies. These self-regulation strategies can be accessed and utilized by students to engage in independent study and help to manage workloads from multiple teachers. The use of a…
ERIC Educational Resources Information Center
Child, Sue
2009-01-01
Within education, the term "research" is used in a multiplicity of ways. This paper draws on my own reflection of how educational practitioners experience shifting relationships to research. It suggests that within the further education (FE) sector, professionalism in teaching is measured through observation in the form of the Ofsted…
ERIC Educational Resources Information Center
van Veen, Saskia C.; de Wildt-Liesveld, Renée; Bunders, Joske F. G.; Regeer, Barbara J.
2014-01-01
Change processes are increasingly seen as the solution to entrenched (social) problems. However, change is difficult to realise while dealing with multiple actors, values, and approaches. (Inter)organisational learning is seen as a way to facilitate reflective practices in social change that support emergent changes, vicarious learning, and…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bidaux, Y., E-mail: yves.bidaux@alpeslasers.ch; Alpes Lasers SA, 1-3 Maximilien-de-Meuron, CH-2000 Neuchatel; Terazzi, R.
2015-09-07
We report spectrally resolved gain measurements and simulations for quantum cascade lasers (QCLs) composed of multiple heterogeneous stacks designed for broadband emission in the mid-infrared. The measurement method is first demonstrated on a reference single active region QCL based on a double-phonon resonance design emitting at 7.8 μm. It is then extended to a three-stack active region based on bound-to-continuum designs with a broadband emission range from 7.5 to 10.5 μm. A tight agreement is found with simulations based on a density matrix model. The latter implements exhaustive microscopic scattering and dephasing sources with virtually no fitting parameters. The quantitative agreement ismore » furthermore assessed by measuring gain coefficients obtained by studying the threshold current dependence with the cavity length. These results are particularly relevant to understand fundamental gain mechanisms in complex semiconductor heterostructure QCLs and to move towards efficient gain engineering. Finally, the method is extended to the measurement of the modal reflectivity of an anti-reflection coating deposited on the front facet of the broadband QCL.« less
Reflection/suppression coatings for 900 - 1200 A radiation
NASA Technical Reports Server (NTRS)
Edelstein, Jerry
1989-01-01
The design and performance of multiple-layer, selective-reflection, selective-suppression coatings for the 900 - 1200 A band are described. These coatings are designed to optimize both high reflectivity at a desirable wavelength and low reflectivity at an undesirable wavelength. The minimum structure for a selective coating consists of a thin metal or metal oxide layer (50 - 150 A thickness) over an aluminum substrate protected with a semi-transparent dielectric (100 - 1000 A thickness). Predicted coating performance is strongly effected by varying the layer combination and thickness. A graphical method of optimizing the coating layer structure is developed. Aluminum, silicon, their oxides, and gold have been investigated as coating layer materials. A very simple coating with a 1026 to 1216 A reflectivity ratio greater than 100 was fabricated. Such reflection/suppression coatings may be of great utility to spaceborne EUV spectrographs.
Estimating big bluestem albedo from directional reflectance measurements
NASA Technical Reports Server (NTRS)
Irons, J. R.; Ranson, K. J.; Daughtry, C. S. T.
1988-01-01
Multidirectional reflectance factor measurements acquired in the summer of 1986 are used to make estimates of big bluestem grass albedo, evaluating the variation of albedo with changes in solar zenith angle and phenology. On any given day, the albedo was observed to increase by at least 19 percent as solar zenith angle increased. Changes in albedo were found to correspond to changes in the green leaf area index of the grass canopy. Estimates of albedo made using reflectance data acquired within only one or two azimuthal planes and at a restricted range of view zenith angle were evaluated and compared to 'true' albedos derived from all available reflectance factor data. It was found that even a limited amount of multiple direction reflectance data was preferable to a single nadir reflectance factor for the estimation of prarie grass albedo.
Bauer, Klaus; Ryberg, Trond; Fuis, Gary S.; Lüth, Stefan
2013-01-01
Near‐vertical faults can be imaged using reflected refractions identified in controlled‐source seismic data. Often theses phases are observed on a few neighboring shot or receiver gathers, resulting in a low‐fold data set. Imaging can be carried out with Kirchhoff prestack depth migration in which migration noise is suppressed by constructive stacking of large amounts of multifold data. Fresnel volume migration can be used for low‐fold data without severe migration noise, as the smearing along isochrones is limited to the first Fresnel zone around the reflection point. We developed a modified Fresnel volume migration technique to enhance imaging of steep faults and to suppress noise and undesired coherent phases. The modifications include target‐oriented filters to separate reflected refractions from steep‐dipping faults and reflections with hyperbolic moveout. Undesired phases like multiple reflections, mode conversions, direct P and S waves, and surface waves are suppressed by these filters. As an alternative approach, we developed a new prestack line‐drawing migration method, which can be considered as a proxy to an infinite frequency approximation of the Fresnel volume migration. The line‐drawing migration is not considering waveform information but requires significantly shorter computational time. Target‐oriented filters were extended by dip filters in the line‐drawing migration method. The migration methods were tested with synthetic data and applied to real data from the Waltham Canyon fault, California. The two techniques are applied best in combination, to design filters and to generate complementary images of steep faults.
Mapping visual cortex in monkeys and humans using surface-based atlases
NASA Technical Reports Server (NTRS)
Van Essen, D. C.; Lewis, J. W.; Drury, H. A.; Hadjikhani, N.; Tootell, R. B.; Bakircioglu, M.; Miller, M. I.
2001-01-01
We have used surface-based atlases of the cerebral cortex to analyze the functional organization of visual cortex in humans and macaque monkeys. The macaque atlas contains multiple partitioning schemes for visual cortex, including a probabilistic atlas of visual areas derived from a recent architectonic study, plus summary schemes that reflect a combination of physiological and anatomical evidence. The human atlas includes a probabilistic map of eight topographically organized visual areas recently mapped using functional MRI. To facilitate comparisons between species, we used surface-based warping to bring functional and geographic landmarks on the macaque map into register with corresponding landmarks on the human map. The results suggest that extrastriate visual cortex outside the known topographically organized areas is dramatically expanded in human compared to macaque cortex, particularly in the parietal lobe.
Microwave reflectometer ionization sensor
NASA Technical Reports Server (NTRS)
Seals, Joseph; Fordham, Jeffrey A.; Pauley, Robert G.; Simonutti, Mario D.
1993-01-01
The development of the Microwave Reflectometer Ionization Sensor (MRIS) Instrument for use on the Aeroassist Flight Experiment (AFE) spacecraft is described. The instrument contract was terminated, due to cancellation of the AFE program, subsequent to testing of an engineering development model. The MRIS, a four-frequency reflectometer, was designed for the detection and location of critical electron density levels in spacecraft reentry plasmas. The instrument would sample the relative magnitude and phase of reflected signals at discrete frequency steps across 4 GHz bandwidths centered at four frequencies: 20, 44, 95, and 140 GHz. The sampled data would be stored for later processing to calculate the distance from the spacecraft surface to the critical electron densities versus time. Four stepped PM CW transmitter receivers were located behind the thermal protection system of the spacecraft with horn antennas radiating and receiving through an insulating tile. Techniques were developed to deal with interference, including multiple reflections and resonance effects, resulting from the antenna configuration and operating environment.
From scientific literacy to sustainability literacy: An ecological framework for education
NASA Astrophysics Data System (ADS)
Colucci-Gray, Laura; Camino, Elena; Barbiero, Giuseppe; Gray, Donald
2006-03-01
In this paper, we report some reflections on science and education, in relation to teaching and research in the field of complex and controversial socio-environmental issues. Starting from an examination of the literature on the epistemological aspects of the science of controversial issues, and introducing the perspective of complexity, the article argues for a complexity of content, context, and method in understanding current problems. Focusing on a model of learning which includes dialogical and reflective approaches, the final part of the article reports on aspect of the authors' experimental practice with role-play for dealing with complex issues. The review of the literature and our experience of action-research introduce a view of education which promotes young people's awareness of multiple points of view, an ability to establish relationships between processes, scales, and contexts which may be nonlinearly related, and practice with creative and nonviolent forms of interrelations with others. Such an approach in science education is coherent with a scenario of planet sustainability based on ecological webs and equity principles.
Reflections on the Last 25 Years of the American Otological Society and Thoughts on its Future.
Welling, D Bradley; Jackler, Robert K
2018-04-01
To review contributions of the American Otological Society (AOS) over the most recent quarter century (1993-2018) and to comment on possible future evolution of the field during the quarter century to come. Retrospective review of selected topics from the AOS transactions, distinguished lectureships over the past 25 years, and selective reflection by the authors. Speculation on potential advances of the next quarter century derived from emerging topics in the current literature and foreseeable trends in science and technology are also proffered for consideration (and possible future ridicule). Integration of multiple disciplines including bioengineering, medical imaging, genetics, molecular biology, physics, and evidence based medicine have substantially benefitted the practice of otology over the past quarter century. The impact of the contributions of members of the AOS in these developments cannot be over estimated. Further scientific advancement will certainly accelerate change in the practice of otologic surgery and medicine over the coming decade in ways that will be marvelous to behold.
Reis, Nádia; Franca, Adriana S; Oliveira, Leandro S
2013-10-15
The current study presents an application of Diffuse Reflectance Infrared Fourier Transform Spectroscopy for detection and quantification of fraudulent addition of commonly employed adulterants (spent coffee grounds, coffee husks, roasted corn and roasted barley) to roasted and ground coffee. Roasted coffee samples were intentionally blended with the adulterants (pure and mixed), with total adulteration levels ranging from 1% to 66% w/w. Partial Least Squares Regression (PLS) was used to relate the processed spectra to the mass fraction of adulterants and the model obtained provided reliable predictions of adulterations at levels as low as 1% w/w. A robust methodology was implemented that included the detection of outliers. High correlation coefficients (0.99 for calibration; 0.98 for validation) coupled with low degrees of error (1.23% for calibration; 2.67% for validation) confirmed that DRIFTS can be a valuable analytical tool for detection and quantification of adulteration in ground, roasted coffee. Copyright © 2013 Elsevier B.V. All rights reserved.
Spectral decomposition of AVIRIS data
NASA Technical Reports Server (NTRS)
Gaddis, Lisa; Soderblom, Laurence; Kieffer, Hugh; Becker, Kris; Torson, Jim; Mullins, Kevin
1993-01-01
A set of techniques is presented that uses only information contained within a raw Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) scene to estimate and to remove additive components such as multiple scattering and instrument dark current. Multiplicative components (instrument gain, topographic modulation of brightness, atmospheric transmission) can then be normalized, permitting enhancement, extraction, and identification of relative reflectance information related to surface composition and mineralogy. The technique for derivation of additive-component spectra from a raw AVIRIS scene is an adaption of the 'regression intersection method' of Crippen. This method uses two surface units that are spatially extensive, and located in rugged terrain. For a given wavelength pair, subtraction of the derived additive component from individual band values will remove topography in both regions in a band/band ratio image. Normalization of all spectra in the scene to the average scene spectrum then results in cancellation of multiplicative components and production of a relative-reflectance scene. The resulting AVIRIS product contains relative-reflectance features due to mineral absorption that depart from the average spectrum. These features commonly are extremely weak and difficult to recognize, but they can be enhanced by using two simple 3-D image-processing tools. The validity of these techniques will be demonstrated by comparisons between relative-reflectance AVIRIS spectra and those derived by using JPL standard calibrations. The AVIRIS data used in this analysis were acquired over the Kelso Dunes area (34 deg 55' N, 115 deg 43' W) of the eastern Mojave Desert, CA (in 1987) and the Upheaval Dome area (38 deg 27' N, 109 deg 55' W) of the Canyonlands National Park, UT (in 1991).
High-fidelity simulations of blast loadings in urban environments using an overset meshing strategy
NASA Astrophysics Data System (ADS)
Wang, X.; Remotigue, M.; Arnoldus, Q.; Janus, M.; Luke, E.; Thompson, D.; Weed, R.; Bessette, G.
2017-05-01
Detailed blast propagation and evolution through multiple structures representing an urban environment were simulated using the code Loci/BLAST, which employs an overset meshing strategy. The use of overset meshes simplifies mesh generation by allowing meshes for individual component geometries to be generated independently. Detailed blast propagation and evolution through multiple structures, wave reflection and interaction between structures, and blast loadings on structures were simulated and analyzed. Predicted results showed good agreement with experimental data generated by the US Army Engineer Research and Development Center. Loci/BLAST results were also found to compare favorably to simulations obtained using the Second-Order Hydrodynamic Automatic Mesh Refinement Code (SHAMRC). The results obtained demonstrated that blast reflections in an urban setting significantly increased the blast loads on adjacent buildings. Correlations of computational results with experimental data yielded valuable insights into the physics of blast propagation, reflection, and interaction under an urban setting and verified the use of Loci/BLAST as a viable tool for urban blast analysis.
Axelrod, Daniel
2012-08-01
Microscopic fluorescent samples of interest to cell and molecular biology are commonly embedded in an aqueous medium near a solid surface that is coated with a thin film such as a lipid multilayer, collagen, acrylamide, or a cell wall. Both excitation and emission of fluorescent single molecules near film-coated surfaces are strongly affected by the proximity of the coated surface, the film thickness, its refractive index and the fluorophore's orientation. For total internal reflection excitation, multiple reflections in the film can lead to resonance peaks in the evanescent intensity versus incidence angle curve. For emission, multiple reflections arising from the fluorophore's near field emission can create a distinct intensity pattern in both the back focal plane and the image plane of a high aperture objective. This theoretical analysis discusses how these features can be used to report film thickness and refractive index, and fluorophore axial position and orientation. © 2012 The Author Journal of Microscopy © 2012 Royal Microscopical Society.
Method for Calculating the Optical Diffuse Reflection Coefficient for the Ocular Fundus
NASA Astrophysics Data System (ADS)
Lisenko, S. A.; Kugeiko, M. M.
2016-07-01
We have developed a method for calculating the optical diffuse reflection coefficient for the ocular fundus, taking into account multiple scattering of light in its layers (retina, epithelium, choroid) and multiple refl ection of light between layers. The method is based on the formulas for optical "combination" of the layers of the medium, in which the optical parameters of the layers (absorption and scattering coefficients) are replaced by some effective values, different for cases of directional and diffuse illumination of the layer. Coefficients relating the effective optical parameters of the layers and the actual values were established based on the results of a Monte Carlo numerical simulation of radiation transport in the medium. We estimate the uncertainties in retrieval of the structural and morphological parameters for the fundus from its diffuse reflectance spectrum using our method. We show that the simulated spectra correspond to the experimental data and that the estimates of the fundus parameters obtained as a result of solving the inverse problem are reasonable.
NASA Astrophysics Data System (ADS)
Hann, Swook; Kim, Dong-Hwan; Park, Chang-Soo
2006-04-01
A monitoring technique for multiple power splitter-passive optical networks (PS-PON) is presented. The technique is based on the remote sensing of fiber Bragg grating (FBG) using a tunable OTDR. To monitor the multiple PS-PON, the FBG can be used for a wavelength dependent reflective reference on each branch end of the PS. The FBG helps discern an individual event of the multiple PS-PON for the monitoring in collaborate with information of Rayleigh backscattered power. The multiple PS-PON can be analyzed by the monitoring method at the central office under 10-Gbit/s in-service.
Derivation of scaled surface reflectances from AVIRIS data
NASA Technical Reports Server (NTRS)
Gao, Bo-Cai; Heidebrecht, Kathleen B.; Goetz, Alexander F. H.
1993-01-01
A method for retrieving 'scaled surface reflectances' assuming horizontal surfaces having Lambertian reflectances from spectral data collected by Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) is presented here. In this method, the integrated water vapor amount on a pixel by pixel basis is derived from the 0.94 micron and 1.14 micron water vapor absorption features. The transmission spectra of H2O, CO2, O3, N2O, CO, CH4, and O2 in the 0.4-2.5 micron region are simulated. The scattering effect due to atmospheric molecules and aerosols is modeled with the 5S computer code. The AVIRIS radiances are divided by solar irradiances above the atmosphere to obtain the apparent reflectances. The scaled surface reflectances are derived from the apparent reflectances using the simulated atmospheric gaseous transmittances and the simulated molecular and aerosol scattering data. The scaled surface reflectances differ from the real surface reflectances by a multiplicative factor. In order to convert the scaled surface reflectances into real surface reflectances, the slopes and aspects of the surfaces must be known.
Tracking Iron in Multiple Sclerosis: A Combined Imaging and Histopathological Study at 7 Tesla
ERIC Educational Resources Information Center
Bagnato, Francesca; Hametner, Simon; Yao, Bing; van Gelderen, Peter; Merkle, Hellmut; Cantor, Fredric K.; Lassmann, Hans; Duyn, Jeff H.
2011-01-01
Previous authors have shown that the transverse relaxivity R[subscript 2][superscript *] and frequency shifts that characterize gradient echo signal decay in magnetic resonance imaging are closely associated with the distribution of iron and myelin in the brain's white matter. In multiple sclerosis, iron accumulation in brain tissue may reflect a…
ERIC Educational Resources Information Center
Warlop, Nele P.; Achten, Eric; Debruyne, Jan; Vingerhoets, Guy
2008-01-01
We aimed to investigate the relation between damage in the corpus callosum and the performance on an interhemispheric communication task in patients with multiple sclerosis (MS). Relative callosal lesion load defined as the ratio between callosal area and the total lesion load in the total corpus callosum, and the diffusion tensor imaging (DTI)…
Detection of stress factors in crop and weed species using hyperspectral remote sensing reflectance
NASA Astrophysics Data System (ADS)
Henry, William Brien
The primary objective of this work was to determine if stress factors such as moisture stress or herbicide injury stress limit the ability to distinguish between weeds and crops using remotely sensed data. Additional objectives included using hyperspectral reflectance data to measure moisture content within a species, and to measure crop injury in response to drift rates of non-selective herbicides. Moisture stress did not reduce the ability to discriminate between species. Regardless of analysis technique, the trend was that as moisture stress increased, so too did the ability to distinguish between species. Signature amplitudes (SA) of the top 5 bands, discrete wavelet transforms (DWT), and multiple indices were promising analysis techniques. Discriminant models created from one year's data set and validated on additional data sets provided, on average, approximately 80% accurate classification among weeds and crop. This suggests that these models are relatively robust and could potentially be used across environmental conditions in field scenarios. Distinguishing between leaves grown at high-moisture stress and no-stress was met with limited success, primarily because there was substantial variation among samples within the treatments. Leaf water potential (LWP) was measured, and these were classified into three categories using indices. Classification accuracies were as high as 68%. The 10 bands most highly correlated to LWP were selected; however, there were no obvious trends or patterns in these top 10 bands with respect to time, species or moisture level, suggesting that LWP is an elusive parameter to quantify spectrally. In order to address herbicide injury stress and its impact on species discrimination, discriminant models were created from combinations of multiple indices. The model created from the second experimental run's data set and validated on the first experimental run's data provided an average of 97% correct classification of soybean and an overall average classification accuracy of 65% for all species. This suggests that these models are relatively robust and could potentially be used across a wide range of herbicide applications in field scenarios. From the pooled data set, a single discriminant model was created with multiple indices that discriminated soybean from weeds 88%, on average, regardless of herbicide, rate or species. Several analysis techniques including multiple indices, signature amplitude with spectral bands as features, and wavelet analysis were employed to distinguish between herbicide-treated and nontreated plants. Classification accuracy using signature amplitude (SA) analysis of paraquat injury on soybean was better than 75% for both 1/2 and 1/8X rates at 1, 4, and 7 DAA. Classification accuracy of paraquat injury on corn was better than 72% for the 1/2X rate at 1, 4, and 7 DAA. These data suggest that hyperspectral reflectance may be used to distinguish between healthy plants and injured plants to which herbicides have been applied; however, the classification accuracies remained at 75% or higher only when the higher rates of herbicide were applied. (Abstract shortened by UMI.)
Electromagnetic scattering by impedance structures
NASA Technical Reports Server (NTRS)
Balanis, Constantine A.; Griesser, Timothy
1987-01-01
The scattering of electromagnetic waves from impedance structures is investigated, and current work on antenna pattern calculation is presented. A general algorithm for determining radiation patterns from antennas mounted near or on polygonal plates is presented. These plates are assumed to be of a material which satisfies the Leontovich (or surface impedance) boundary condition. Calculated patterns including reflection and diffraction terms are presented for numerious geometries, and refinements are included for antennas mounted directly on impedance surfaces. For the case of a monopole mounted on a surface impedance ground plane, computed patterns are compared with experimental measurements. This work in antenna pattern prediction forms the basis of understanding of the complex scattering mechanisms from impedance surfaces. It provides the foundation for the analysis of backscattering patterns which, in general, are more problematic than calculation of antenna patterns. Further proposed study of related topics, including surface waves, corner diffractions, and multiple diffractions, is outlined.
Baba, Justin S.
2015-11-24
Refractometers for simultaneously measuring refractive index of a sample over a range or wavelengths of light include dispersive and focusing optical systems. An optical beam including the rang of wavelengths is spectrally spread along a first axis and focused along a second axis so as to be incident to an interface between the sample and a prism at a range of angles of incidence including a critical angle for at least one wavelength. In some cases, the prism can have a triangle, parallelogram, trapezoid, or other shape. In some cases, the optical beam can be reflected off of multiple interfaces between the prism and the sample. An imaging detector is situated to receive the spectrally spread and focused light from the interface and form an image corresponding to angle of incidence as a function of wavelength. One or more critical angles are indentified and corresponding refractive indices are determined.
Two-dimensional PSF prediction of multiple-reflection optical systems with rough surfaces
NASA Astrophysics Data System (ADS)
Tayabaly, Kashmira; Spiga, Daniele; Sironi, Giorgia; Pareschi, Giovani; Lavagna, Michele
2016-09-01
The focusing accuracy in reflective optical systems, usually expressed in terms of the Point Spread Function (PSF) is chiefly determined by two factors: the deviation of the mirror shape from the nominal design and the surface finishing. While the effects of the former are usually well described by the geometrical optics, the latter is diffractive/interferential in nature and determined by a distribution of defects that cover several decades in the lateral scale (from a few millimeters to a few microns). Clearly, reducing the level of scattered light is crucial to improve the focusing of the collected radiation, particularly for astronomical telescopes that aim to detect faint light signals from our Universe. Telescopes are typically arranged in multiple reflections configuration and the behavior of the multiply-scattered radiation becomes difficult to predict and control. Also it is difficult to disentangle the effect of surface scattering from the PSF degradation caused by the shape deformation of the optical elements. This paper presents a simple and unifying method for evaluating the contribution of optical surfaces defects to the two-dimensional PSF of a multi-reflections system, regardless of the classification of a spectral range as "geometry" or "roughness". This method, entirely based on Huygens-Fresnel principle in the far-field approximation, was already applied in grazing-incidence X-ray mirrors and experimentally validated for a single reflection system, accounting for the real surface topography of the optics. In this work we show the extension of this formalism to a double reflection system and introducing real microroughness data. The formalism is applied to a MAGIC-I panel mirror that was fully characterized, allowing us to predict the PSF and the validation with real measurements of the double reflection ASTRI telescope, a prototype of CTA-SST telescope.
Basin-ring spacing on the Moon, Mercury, and Mars
Pike, R.J.; Spudis, P.D.
1987-01-01
Radial spacing between concentric rings of impact basins that lack central peaks is statistically similar and nonrandom on the Moon, Mercury, and Mars, both inside and outside the main ring. One spacing interval, (2.0 ?? 0.3)0.5D, or an integer multiple of it, dominates most basin rings. Three analytical approaches yield similar results from 296 remapped or newly mapped rings of 67 multi-ringed basins: least-squares of rank-grouped rings, least-squares of rank and ring diameter for each basin, and averaged ratios of adjacent rings. Analysis of 106 rings of 53 two-ring basins by the first and third methods yields an integer multiple (2 ??) of 2.00.5D. There are two exceptions: (1) Rings adjacent to the main ring of multi-ring basins are consistently spaced at a slightly, but significantly, larger interval, (2.1 ?? 0.3)0.5D; (2) The 88 rings of 44 protobasins (large peak-plus-inner-ring craters) are spaced at an entirely different interval (3.3 ?? 0.6)0.5D. The statistically constant and target-invariant spacing of so many rings suggests that this characteristic may constrain formational models of impact basins on the terrestrial planets. The key elements of such a constraint include: (1) ring positions may not have been located by the same process(es) that formed ring topography; (2) ring location and emplacement of ring topography need not be coeval; (3) ring location, but not necessarily the mode of ring emplacement, reflects one process that operated at the time of impact; and (4) the process yields similarly-disposed topographic features that are spatially discrete at 20.5D intervals, or some multiple, rather than continuous. These four elements suggest that some type of wave mechanism dominates the location, but not necessarily the formation, of basin rings. The waves may be standing, rather than travelling. The ring topography itself may be emplaced at impact by this and/or other mechanisms and may reflect additional, including post-impact, influences. ?? 1987 D. Reidel Publishing Company.
Ren, Huazhong; Liu, Rongyuan; Yan, Guangjian; Li, Zhao-Liang; Qin, Qiming; Liu, Qiang; Nerry, Françoise
2015-04-06
Land surface emissivity is a crucial parameter in the surface status monitoring. This study aims at the evaluation of four directional emissivity models, including two bi-directional reflectance distribution function (BRDF) models and two gap-frequency-based models. Results showed that the kernel-driven BRDF model could well represent directional emissivity with an error less than 0.002, and was consequently used to retrieve emissivity with an accuracy of about 0.012 from an airborne multi-angular thermal infrared data set. Furthermore, we updated the cavity effect factor relating to multiple scattering inside canopy, which improved the performance of the gap-frequency-based models.
Nineteenth International Laser Radar Conference. Part 2
NASA Technical Reports Server (NTRS)
Singh, Upendra N. (Editor); Ismail, Syed (Editor); Schwemmer, Geary K. (Editor)
1998-01-01
This publication contains extended abstracts of papers presented at the Nineteenth International Laser Radar Conference, held at Annapolis, Maryland, July 6-10, 1998; 260 papers were presented in both oral and poster sessions. The topics of the conference sessions were Aerosol Clouds, Multiple Scattering; Tropospheric Profiling, Stratospheric/Mesospheric Profiling; Wind Profiling; New Lidar Technology and Techniques; Lidar Applications, Including Altimetry and Marine; Space and Future Lidar; and Lidar Commercialization/Eye Safety. This conference reflects the breadth of research activities being conducted in the lidar field. These abstracts address subjects from lidar-based atmospheric investigations, development of new lasers and lidar system technology, and current and future space-based lidar systems.
Nineteenth International Laser Radar Conference. Part 1
NASA Technical Reports Server (NTRS)
Singh, Upendra N. (Editor); Ismail, Syed (Editor); Schwemmer, Geary K. (Editor)
1998-01-01
This publication contains extended abstracts of papers presented at the Nineteenth International Laser Radar Conference, held at Annapolis, Maryland, July 6-10, 1998; 260 papers were presented in both oral and poster sessions. The topics of the conference sessions were Aerosol Clouds, Multiple Scattering; Tropospheric Profiling; Stratospheric/Mesospheric Profiling; Wind Profiling; New Lidar Technology and Techniques; Lidar Applications, including Altimetry and Marine; Space and Future Lidar; and Lidar Commercialization/Eye Safety. This conference reflects the breadth of research activities being conducted in the lidar field. These abstracts address subjects from lidar-based atmospheric investigations, development of new lasers and lidar system technology, and current and future space-based lidar systems.
Multi-wavelength laser from dye-doped cholesteric polymer films.
Huang, Yuhua; Wu, Shin-Tson
2010-12-20
A multi-wavelength laser is demonstrated using a dye-doped cholesteric polymer film whose reflection bandwidth is broadened with several oscillations. Due to the abrupt change of the density of state between oscillation peak and valley, each oscillation functions as a photonic band gap for generating a laser wavelength under the excitation of a pumping laser. As a result, a multiple wavelength laser is generated. Results indicate that the dye-doped cholesteric liquid crystal polymer film is a good candidate for fabricating broadband lasers such as white light lasers. Potential applications include experimental testing of laser materials, identification markers, information displays, and inertial confinement laser fusion.
Genetic and Environmental Influences on Odor Identification Ability in the Very Old
Doty, Richard L.; Petersen, Inge; Mensah, Nii; Christensen, Kaare
2013-01-01
Odor identification ability and cognition were measured in a population-based cohort of 1,222 very old twins and singletons, including 91 centenarians. Heritability for identifying odors was low, in contrast to that for cognition. Common genes were found to contribute to both olfaction and cognition. In a multiple regression model, sex, age, cognitive function, and smoking, but not APOEε4 status, were significant predictors of the olfactory test scores (all ps < 0.001). This study, along with data from other studies, suggests that indices of heritability for odor identification decline with age, likely reflecting adverse environmental influences on the smell system. PMID:21639645
NCSP IER 422 CED-3b Documentation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hutchinson, Jesson D.; Cutler, Theresa Elizabeth; Bahran, Rian Mustafa
2017-11-22
A Subcritical Copper-Reflected α-phase Plutonium (SCRαP) integral benchmark experiment has been designed and measured. In this experiment, multiplication is approximated using correlated neutron data from a detector system consisting of 3He tubes inside high density polyethylene (HDPE). Measurements were performed on various subcritical experimental configurations consisting of a weapons-grade plutonium sphere surrounded by different Cu thicknesses. In addition to the proposed base experimental configurations with Cu, additional configurations were performed with the plutonium ball nested in various thicknesses of interleaved HDPE spherical shells mixed in with the Cu shells. The HDPE is intended to provide fast neutron moderation and reflection,more » resulting in additional measurements with differing multiplication, spectra, and nuclear data sensitivity.« less
NASA Technical Reports Server (NTRS)
Meneghini, Robert; Liao, Liang
2013-01-01
As shown by Takahashi et al., multiple path attenuation estimates over the field of view of an airborne or spaceborne weather radar are feasible for off-nadir incidence angles. This follows from the fact that the surface reference technique, which provides path attenuation estimates, can be applied to each radar range gate that intersects the surface. This study builds on this result by showing that three of the modified Hitschfeld-Bordan estimates for the attenuation-corrected radar reflectivity factor can be generalized to the case where multiple path attenuation estimates are available, thereby providing a correction to the effects of nonuniform beamfilling. A simple simulation is presented showing some strengths and weaknesses of the approach.
ERIC Educational Resources Information Center
Cho, Jeong il
2012-01-01
This reflection is based on my project that investigated the impact of new course content on student learning of basic knowledge and attitudes toward various assistive technology (AT) devices and services using multiple measures in an introductory-level course in a special education program at Indiana University-Purdue University Fort Wayne.…
The albedo of particles in reflection nebulae
NASA Technical Reports Server (NTRS)
Rush, W. F.
1974-01-01
The relation between the apparent angular extent of a reflection nebula and the apparent magnitude of its illuminating star was reconsidered under a less restrictive set of assumptions. A computational technique was developed which permits the use of fits to the observed m-log a values to determine the albedo of particles composing reflection nebulae, providing only that a phase function and average optical thickness are assumed. Multiple scattering, anisotropic phase functions, and illumination by the general star field are considered, and the albedo of reflection nebular particles appears to be the same as that for interstellar particles in general. The possibility of continuous fluorescence contributions to the surface brightness is also considered.
See, reflect, learn more: qualitative analysis of breaking bad news reflective narratives.
Karnieli-Miller, Orit; Palombo, Michal; Meitar, Dafna
2018-05-01
Breaking bad news (BBN) is a challenge that requires multiple professional competencies. BBN teaching often includes didactic and group role-playing sessions. Both are useful and important, but exclude another critical component of students' learning: day-to-day role-model observation in the clinics. Given the importance of observation and the potential benefit of reflective writing in teaching, we have incorporated reflective writing into our BBN course. The aim of this study was to enhance our understanding of the learning potential in reflective writing about BBN encounters and the ability to identify components that inhibit this learning. This was a systematic qualitative immersion/crystallization analysis of 166 randomly selected BBN narratives written by 83 senior medical students. We analysed the narratives in an iterative consensus-building process to identify the issues discussed, the lessons learned and the enhanced understanding of BBN. Having previously been unaware of, not invited to or having avoided BBN encounters, the mandatory assignment led students to search for or ask their mentors to join them in BBN encounters. Observation and reflective writing enhanced students' awareness that 'bad news' is relative and subjective, while shedding light on patients', families', physicians' and their own experiences and needs, revealing the importance of the different components of the BBN protocol. We identified diversity among the narratives and the extent of students' learning. Narrative writing provided students with an opportunity for a deliberative learning process. This led to deeper understanding of BBN encounters, of how to apply the newly taught protocol, or of the need for it. This process connected the formal and informal or hidden curricula. To maximise learning through reflective writing, students should be encouraged to write in detail about a recent observed encounter, analyse it according to the protocol, address different participants' behaviours and emotions, and identify dilemmas and clear lessons learned. © 2018 John Wiley & Sons Ltd and The Association for the Study of Medical Education.
Homogenization of Electromagnetic and Seismic Wavefields for Joint Inverse Modeling
NASA Astrophysics Data System (ADS)
Newman, G. A.; Commer, M.; Petrov, P.; Um, E. S.
2011-12-01
A significant obstacle in developing a robust joint imaging technology exploiting seismic and electromagnetic (EM) wave fields is the resolution at which these different geophysical measurements sense the subsurface. Imaging of seismic reflection data is an order of magnitude finer in resolution and scale compared to images produced with EM data. A consistent joint image of the subsurface geophysical attributes (velocity, electrical conductivity) requires/demands the different geophysical data types be similar in their resolution of the subsurface. The superior resolution of seismic data results from the fact that the energy propagates as a wave, while propagation of EM energy is diffusive and attenuates with distance. On the other hand, the complexity of the seismic wave field can be a significant problem due to high reflectivity of the subsurface and the generation of multiple scattering events. While seismic wave fields have been very useful in mapping the subsurface for energy resources, too much scattering and too many reflections can lead to difficulties in imaging and interpreting seismic data. To overcome these obstacles a formulation for joint imaging of seismic and EM wave fields is introduced, where each data type is matched in resolution. In order to accomplish this, seismic data are first transformed into the Laplace-Fourier Domain, which changes the modeling of the seismic wave field from wave propagation to diffusion. Though high frequency information (reflectivity) is lost with this transformation, several benefits follow: (1) seismic and EM data can be easily matched in resolution, governed by the same physics of diffusion, (2) standard least squares inversion works well with diffusive type problems including both transformed seismic and EM, (3) joint imaging of seismic and EM data may produce better starting velocity models critical for successful reverse time migration or full waveform imaging of seismic data (non transformed) and (4) possibilities to image across multiple scale lengths, incorporating different types of geophysical data and attributes in the process. Important numerical details of 3D seismic wave field simulation in the Laplace-Fourier domain for both acoustic and elastic cases will also be discussed.
NASA Astrophysics Data System (ADS)
Bishop, J. L.; Hamilton, V. E.
2001-12-01
Martian meteorites provide direct information about crustal rocks on Mars. In this study we are measuring reflectance and emittance spectra of multiple Martian meteorites in order to characterize the spectral properties of the minerals present and to develop comprehensive criteria for remote detection of rocks and minerals. Previous studies have evaluated mid-IR emittance spectra [Hamilton et al., 1997] and visible/IR reflectance spectra [Bishop et al., 1998a,b] of Martian meteorites independently. The current study includes comparisons of the visible/NIR and mid-IR spectral regions and also involves comparison of mid-IR spectra measured using biconical reflectance and thermal emission techniques. Combining spectral analyses of Martian meteorite chips and powders enables characterization of spectral bands for remote detection of potential source regions for meteorite-like rocks on the surface of Mars using both Thermal Emission Spectrometer (TES) datasets and visible/NIR datasets from past and future missions. Identification of alteration minerals in these meteorites also provides insights into the alteration processes taking place on Mars. Analysis of TES data on Mars has identified global regions of basaltic and andesitic surface material [e.g. Bandfield et al., 2000; Christensen et al., 2000]; however neither of these spectral endmembers corresponds well to the spectra of Martian meteorites. Some preliminary findings suggest that small regions on the surface of Mars may relate to meteorite compositions [e.g. Hoefen et al., 2000; Hamilton et al., 2001]. Part of the difficulty in identifying meteorite compositions on Mars may be due to surface alteration. We hope to apply the results of our spectroscopic analyses of Martian meteorites, as well as fresh and altered basaltic material, toward analysis of composition on Mars using multiple spectral datasets. References: Bandfield J. et al., Science 287, 1626, 2000. Bishop J. et al., MAPS 33, 699, 1998a. Bishop J. et al., MAPS 33, 693, 1998b. Christensen P., et al., JGR 105, 9609, 2000. Hamilton V. et al., JGR 102, 25593, 1997. Hamilton V. et al., LPSC XXXII, #2184, 2001. Hoefen T. et al., Bull. Am. Astron. Soc. 32, 1118, 2000.
On the Electrification of Pyrocumulus Clouds
NASA Technical Reports Server (NTRS)
Lang, Timothy J.; Rutledge, Steven A.; Dolan, Brenda; Krehbiel, Paul; Rison, William; Lindsey, Daniel T.
2013-01-01
The electrification (or lack thereof) of pyrocumulus clouds is examined for several different wildfires that occurred during 2012-2013. For example, pyrocumulus clouds above three Colorado wildfires (Hewlett Gulch, High Park, and Waldo Canyon; all occurred during summer 2012) electrified and produced small intracloud discharges whenever the smoke plumes grew to high altitudes (over 10 km above mean sea level, or MSL). This occurred during periods of rapid wildfire growth, as indicated by the shortwave infrared channel on a geostationary satellite, as well as by incident reports. In the Hewlett Gulch case, the fire growth led to increased updrafts within the plume, as inferred by multiple-Doppler radar syntheses, which led to the vertical development and subsequent electrification - a life cycle as short as 30 minutes. The lightning, detected by a three-dimensional lightning mapping network, was favored in high-altitude regions (10 km MSL) containing modest reflectivities (25 dBZ and lower), 0 dB differential reflectivity, and reduced correlation coefficient (0.6-0.7). This indicated the likely presence of ice particles (crystals and aggregates, possibly rimed) mixed with ash. Though neither multiple-Doppler nor polarimetric observations were available during the electrification of the High Park and Waldo Canyon plumes, their NEXRAD observations showed reflectivity structures consistent with Hewlett Gulch. In addition, polarimetric and multiple-Doppler scanning of unelectrified High Park plumes indicated only irregularly shaped ash, and not ice, was present (i.e., reflectivities < 25 dBZ, differential reflectivity > 5 dB, correlation < 0.4), and there was no broaching of the 10 km altitude. Based on these results, the electrification likely was caused by ice-based processes that did not involve significant amounts of graupel. Results for pyrocumulus clouds above notable 2013 wildfires that also experienced rapid growth (e.g., Black Forest, Yarnell Hill, West Fork, Tres Lagunas, etc.) will be compared against the 2012 cases, with special emphasis on polarimetric NEXRAD and available lightning measurements, in order to better understand the physical processes responsible for pyrocumulus electrification.
Laser illumination of multiple capillaries that form a waveguide
Dhadwal, Harbans S.; Quesada, Mark A.; Studier, F. William
1998-08-04
A system and method are disclosed for efficient laser illumination of the interiors of multiple capillaries simultaneously, and collection of light emitted from them. Capillaries in a parallel array can form an optical waveguide wherein refraction at the cylindrical surfaces confines side-on illuminating light to the core of each successive capillary in the array. Methods are provided for determining conditions where capillaries will form a waveguide and for assessing and minimizing losses due to reflection. Light can be delivered to the arrayed capillaries through an integrated fiber optic transmitter or through a pair of such transmitters aligned coaxially at opposite sides of the array. Light emitted from materials within the capillaries can be carried to a detection system through optical fibers, each of which collects light from a single capillary, with little cross talk between the capillaries. The collection ends of the optical fibers can be in a parallel array with the same spacing as the capillary array, so that the collection fibers can all be aligned to the capillaries simultaneously. Applicability includes improving the efficiency of many analytical methods that use capillaries, including particularly high-throughput DNA sequencing and diagnostic methods based on capillary electrophoresis.
Laser illumination of multiple capillaries that form a waveguide
Dhadwal, H.S.; Quesada, M.A.; Studier, F.W.
1998-08-04
A system and method are disclosed for efficient laser illumination of the interiors of multiple capillaries simultaneously, and collection of light emitted from them. Capillaries in a parallel array can form an optical waveguide wherein refraction at the cylindrical surfaces confines side-on illuminating light to the core of each successive capillary in the array. Methods are provided for determining conditions where capillaries will form a waveguide and for assessing and minimizing losses due to reflection. Light can be delivered to the arrayed capillaries through an integrated fiber optic transmitter or through a pair of such transmitters aligned coaxially at opposite sides of the array. Light emitted from materials within the capillaries can be carried to a detection system through optical fibers, each of which collects light from a single capillary, with little cross talk between the capillaries. The collection ends of the optical fibers can be in a parallel array with the same spacing as the capillary array, so that the collection fibers can all be aligned to the capillaries simultaneously. Applicability includes improving the efficiency of many analytical methods that use capillaries, including particularly high-throughput DNA sequencing and diagnostic methods based on capillary electrophoresis. 35 figs.
Allergen source materials: state-of-the-art.
Esch, Robert E
2009-01-01
A variety of positive outcomes can be realized from validation and risk management activities (see Table 4). They are dependent on the participation of multiple functional groups including the quality unit, regulatory and legal affairs, engineering and production operations, research and development, and sales and marketing. Quality risk management is receiving increased attention in the area of public health, pharmacovigilance, and pharmaceutical manufacturing. Recent examples of its regulatory use in our industry include the assessment of the potential risks of transmissible spongiform encephalopathies (TSE) agents through contaminated products], the risks of precipitates in allergenic extracts, and the revision of the potency limits for standardized dust mite and grass allergen vaccines. Its application to allergen source material process validation activities allowed for a practical strategy, especially in a complex manufacturing environment involving hundreds of products with multiple intended uses. In addition, the use of tools such as FMEA was useful in evaluating proposed changes made to manufacturing procedures and product specifications, new regulatory actions, and customer feedback or complaints. The success of such a quality assurance programs will ultimately be reflected in the elimination or reduction of product failures, improvement in the detection and prediction of potential product failures, and increased confidence in product quality.
Undiagnosed neurological disease as a potential cause of male lower urinary tract symptoms.
Wei, Diana Y; Drake, Marcus J
2016-01-01
In the central nervous system there are many regulatory processes controlling the lower urinary tract. This review considers the possibility that urinary dysfunction may precede diagnosis of neurological disease. Lower urinary tract symptoms (LUTS) occur early in multiple system atrophy, Parkinson's disease and normal pressure hydrocephalus, and may present before neurological diagnosis. Some people present with LUTS and subsequently are diagnosed with multiple sclerosis or a spinal condition. In male LUTS, the symptoms could reflect early stages of a neurological disease, which has not yet been diagnosed ('occult neurology'). Key symptoms include erectile dysfunction, retrograde ejaculation, enuresis, loss of filling sensation or unexplained stress urinary incontinence. Directed questioning should enquire about visual symptoms, back pain, anosmia, bowel dysfunction and incontinence, or memory loss. Examination features can include resting tremor, 'croaky' speech, abnormal gait, orthostatic hypotension, ataxia, or altered perineal sensation. Imaging, such as MRI scan, should only be requested after expert neurological examination, to ensure the correct parts of the central nervous system are scanned with appropriate radiological protocols. Urologists should consider an undiagnosed neurological condition can be present in a few cases. Any finding should be further evaluated by colleagues with relevant expertise.
Jin, Rui; Zhang, Bing
2012-11-01
Chinese herbal property theory (CHPT) is the fundamental characteristic of Chinese materia medica different from modern medicines. It reflects the herbal properties associated with efficacy and formed the early framework of four properties and five flavors in Shennong's Classic of Materia Medica. After the supplement and improvement of CHPT in the past thousands of years, it has developed a theory system including four properties, five flavors, meridian entry, direction of medicinal actions (ascending, descending, floating and sinking) and toxicity. However, because of the influence of philosophy about yin-yang theory and five-phase theory and the difference of cognitive approach and historical background at different times, CHPT became complex. One of the complexity features was the multiple methods for determining herbal property, which might include the inference from herbal efficacy, the thought of Chinese Taoist School and witchcraft, the classification thinking according to manifestations, etc. Another complexity feature was the multiselection associations between herbal property and efficacy, which indicated that the same property could be inferred from different kinds of efficacy. This paper analyzed these complexity features and provided the importance of cognitive approaches and efficacy attributes corresponding to certain herbal property in the study of CHPT.
NASA Astrophysics Data System (ADS)
Nishidate, Izumi; Wiswadarma, Aditya; Hase, Yota; Tanaka, Noriyuki; Maeda, Takaaki; Niizeki, Kyuichi; Aizu, Yoshihisa
2011-08-01
In order to visualize melanin and blood concentrations and oxygen saturation in human skin tissue, a simple imaging technique based on multispectral diffuse reflectance images acquired at six wavelengths (500, 520, 540, 560, 580 and 600nm) was developed. The technique utilizes multiple regression analysis aided by Monte Carlo simulation for diffuse reflectance spectra. Using the absorbance spectrum as a response variable and the extinction coefficients of melanin, oxygenated hemoglobin, and deoxygenated hemoglobin as predictor variables, multiple regression analysis provides regression coefficients. Concentrations of melanin and total blood are then determined from the regression coefficients using conversion vectors that are deduced numerically in advance, while oxygen saturation is obtained directly from the regression coefficients. Experiments with a tissue-like agar gel phantom validated the method. In vivo experiments with human skin of the human hand during upper limb occlusion and of the inner forearm exposed to UV irradiation demonstrated the ability of the method to evaluate physiological reactions of human skin tissue.
Lee, Yu; Yu, Chanki; Lee, Sang Wook
2018-01-10
We present a sequential fitting-and-separating algorithm for surface reflectance components that separates individual dominant reflectance components and simultaneously estimates the corresponding bidirectional reflectance distribution function (BRDF) parameters from the separated reflectance values. We tackle the estimation of a Lafortune BRDF model, which combines a nonLambertian diffuse reflection and multiple specular reflectance components with a different specular lobe. Our proposed method infers the appropriate number of BRDF lobes and their parameters by separating and estimating each of the reflectance components using an interval analysis-based branch-and-bound method in conjunction with iterative K-ordered scale estimation. The focus of this paper is the estimation of the Lafortune BRDF model. Nevertheless, our proposed method can be applied to other analytical BRDF models such as the Cook-Torrance and Ward models. Experiments were carried out to validate the proposed method using isotropic materials from the Mitsubishi Electric Research Laboratories-Massachusetts Institute of Technology (MERL-MIT) BRDF database, and the results show that our method is superior to a conventional minimization algorithm.
ERIC Educational Resources Information Center
Feenaughty, Lynda; Tjaden, Kris; Benedict, Ralph H. B.; Weinstock-Guttman, Bianca
2013-01-01
This preliminary study investigated how cognitive-linguistic status in multiple sclerosis (MS) is reflected in two speech tasks (i.e. oral reading, narrative) that differ in cognitive-linguistic demand. Twenty individuals with MS were selected to comprise High and Low performance groups based on clinical tests of executive function and information…
ERIC Educational Resources Information Center
Hidson, Elizabeth
2018-01-01
A growing body of literature recognizes the affordances of video in education, especially in relation to lesson observation and reflection as part of teachers' initial teacher education and continuing professional development. Minimal attention has been paid to the outcomes of video-enhanced observation as a source of multiple modes of data for…
Phase matrix induced symmetrics for multiple scattering using the matrix operator method
NASA Technical Reports Server (NTRS)
Hitzfelder, S. J.; Kattawar, G. W.
1973-01-01
Entirely rigorous proofs of the symmetries induced by the phase matrix into the reflection and transmission operators used in the matrix operator theory are given. Results are obtained for multiple scattering in both homogeneous and inhomogeneous atmospheres. These results will be useful to researchers using the method since large savings in computer time and storage are obtainable.
Wafer characteristics via reflectometry
Sopori, Bhushan L.
2010-10-19
Various exemplary methods (800, 900, 1000, 1100) are directed to determining wafer thickness and/or wafer surface characteristics. An exemplary method (900) includes measuring reflectance of a wafer and comparing the measured reflectance to a calculated reflectance or a reflectance stored in a database. Another exemplary method (800) includes positioning a wafer on a reflecting support to extend a reflectance range. An exemplary device (200) has an input (210), analysis modules (222-228) and optionally a database (230). Various exemplary reflectometer chambers (1300, 1400) include radiation sources positioned at a first altitudinal angle (1308, 1408) and at a second altitudinal angle (1312, 1412). An exemplary method includes selecting radiation sources positioned at various altitudinal angles. An exemplary element (1650, 1850) includes a first aperture (1654, 1854) and a second aperture (1658, 1858) that can transmit reflected radiation to a fiber and an imager, respectfully.
Ikanga, Jean; Hill, Elizabeth M; MacDonald, Douglas A
2017-02-01
The examination of cognitive reserve (CR) literature reveals a lack of consensus regarding conceptualization and pervasive problems with its measurement. This study aimed at examining the conceptual nature of CR through the analysis of reflective and formative models using eight proxies commonly employed in the CR literature. We hypothesized that all CR proxies would significantly contribute to a one-factor reflective model and that educational and occupational attainment would produce the strongest loadings on a single CR factor. The sample consisted of 149 participants (82 male/67 female), with 18.1 average years of education and ages of 45-99 years. Participants were assessed for eight proxies of CR (parent socioeconomic status, intellectual functioning, level of education, health literacy, occupational prestige, life leisure activities, physical activities, and spiritual and religious activities). Primary statistical analyses consisted of confirmatory factor analysis (CFA) to test reflective models and structural equation modeling (SEM) to evaluate multiple indicators multiple causes (MIMIC) models. CFA did not produce compelling support for a unitary CR construct when using all eight of our CR proxy variables in a reflective model but fairly cogent evidence for a one-factor model with four variable proxies. A second three-factor reflective model based upon an exploratory principal components analysis of the eight proxies was tested using CFA. Though all eight indicators significantly loaded on their assigned factors, evidence in support of overall model fit was mixed. Based upon the results involving the three-factor reflective model, two alternative formative models were developed and evaluated. While some support was obtained for both, the model in which the formative influences were specified as latent variables appeared to best account for the contributions of all eight proxies to the CR construct. While the findings provide partial support for our hypothesis regarding CR as a one-dimensional reflective construct, the results strongly suggest that the construct is more complex than what can be captured in a reflective model alone. There is a need for theory to better identify and differentiate formative from reflective indicators and to articulate the mechanisms by which CR develops and operates.
Experience-based Learning in Acadia National Park: a Successful, Long-running, Model Field Course
NASA Astrophysics Data System (ADS)
Connaughton, M.
2015-12-01
This two-week field course has been offered alternate summers since 2000 in Acadia National Park on Mount Desert Island, Maine and addresses the geological history, physical and biological oceanography and principles of community ecology applicable to terrestrial and/or marine communities of coastal Maine. The course is often transformative and deeply meaningful to the students, many of whom have limited travel experience. The essential components of experience-based learning are well represented in this class with multiple opportunities for abstract conceptualization, active experimentation, concrete hands-on experiences and reflective observation built into the course. Each day begins with a lecture introducing concepts, which are then made concrete though daily field trips (4-8 hours in duration) into the park that include rigorous hiking, some kayaking and one commercial nature cruise. Field trips include hands-on experience with lecture concepts, on-site lessons in field methods, and data collection for independent projects. Each field trip is tied to a specific independent project, which are generated by the instructor, but self-selected by the students. Every student is actively involved in data collection during each field trip, with one student in charge of the collection each day. Daily guided journaling in three parts (scientific, personal and creative) and evening discussions provide ample opportunity for the student to reflect on the scientific content of the course, examine their personal reactions to what they have experienced and to be creative, sharing prior experiences, prior learning and their personalities. The course includes two exams, each following a week of lecture and field experiences. Independent research projects include the production of a manuscript-formatted report complete with statistical analysis of the data and a literature-based discussion of the conclusions. The combination of experiential reinforcement of concepts, abundant opportunity for written and spoken reflection, the beauty of the setting, the challenges of working in the field and the resultant bonding of the students and instructors provide a highly effective and unforgettable learning experience.
NASA Astrophysics Data System (ADS)
von Beeren, Christoph; Stoeckle, Mark Y.; Xia, Joyce; Burke, Griffin; Kronauer, Daniel J. C.
2015-02-01
DNA barcoding promises to be a useful tool to identify pest species assuming adequate representation of genetic variants in a reference library. Here we examined mitochondrial DNA barcodes in a global urban pest, the American cockroach (Periplaneta americana). Our sampling effort generated 284 cockroach specimens, most from New York City, plus 15 additional U.S. states and six other countries, enabling the first large-scale survey of P. americana barcode variation. Periplaneta americana barcode sequences (n = 247, including 24 GenBank records) formed a monophyletic lineage separate from other Periplaneta species. We found three distinct P. americana haplogroups with relatively small differences within (<=0.6%) and larger differences among groups (2.4%-4.7%). This could be interpreted as indicative of multiple cryptic species. However, nuclear DNA sequences (n = 77 specimens) revealed extensive gene flow among mitochondrial haplogroups, confirming a single species. This unusual genetic pattern likely reflects multiple introductions from genetically divergent source populations, followed by interbreeding in the invasive range. Our findings highlight the need for comprehensive reference databases in DNA barcoding studies, especially when dealing with invasive populations that might be derived from multiple genetically distinct source populations.
Monitoring heavy metal Cr in soil based on hyperspectral data using regression analysis
NASA Astrophysics Data System (ADS)
Zhang, Ningyu; Xu, Fuyun; Zhuang, Shidong; He, Changwei
2016-10-01
Heavy metal pollution in soils is one of the most critical problems in the global ecology and environment safety nowadays. Hyperspectral remote sensing and its application is capable of high speed, low cost, less risk and less damage, and provides a good method for detecting heavy metals in soil. This paper proposed a new idea of applying regression analysis of stepwise multiple regression between the spectral data and monitoring the amount of heavy metal Cr by sample points in soil for environmental protection. In the measurement, a FieldSpec HandHeld spectroradiometer is used to collect reflectance spectra of sample points over the wavelength range of 325-1075 nm. Then the spectral data measured by the spectroradiometer is preprocessed to reduced the influence of the external factors, and the preprocessed methods include first-order differential equation, second-order differential equation and continuum removal method. The algorithms of stepwise multiple regression are established accordingly, and the accuracy of each equation is tested. The results showed that the accuracy of first-order differential equation works best, which makes it feasible to predict the content of heavy metal Cr by using stepwise multiple regression.
Mollison, Daisy; Sellar, Robin; Bastin, Mark; Mollison, Denis; Chandran, Siddharthan; Wardlaw, Joanna; Connick, Peter
2017-01-01
Moderate correlation exists between the imaging quantification of brain white matter lesions and cognitive performance in people with multiple sclerosis (MS). This may reflect the greater importance of other features, including subvisible pathology, or methodological limitations of the primary literature. To summarise the cognitive clinico-radiological paradox and explore the potential methodological factors that could influence the assessment of this relationship. Systematic review and meta-analysis of primary research relating cognitive function to white matter lesion burden. Fifty papers met eligibility criteria for review, and meta-analysis of overall results was possible in thirty-two (2050 participants). Aggregate correlation between cognition and T2 lesion burden was r = -0.30 (95% confidence interval: -0.34, -0.26). Wide methodological variability was seen, particularly related to key factors in the cognitive data capture and image analysis techniques. Resolving the persistent clinico-radiological paradox will likely require simultaneous evaluation of multiple components of the complex pathology using optimum measurement techniques for both cognitive and MRI feature quantification. We recommend a consensus initiative to support common standards for image analysis in MS, enabling benchmarking while also supporting ongoing innovation.
NASA Astrophysics Data System (ADS)
Zhang, Yang; Liu, Wei; Li, Xiaodong; Yang, Fan; Gao, Peng; Jia, Zhenyuan
2015-10-01
Large-scale triangulation scanning measurement systems are widely used to measure the three-dimensional profile of large-scale components and parts. The accuracy and speed of the laser stripe center extraction are essential for guaranteeing the accuracy and efficiency of the measuring system. However, in the process of large-scale measurement, multiple factors can cause deviation of the laser stripe center, including the spatial light intensity distribution, material reflectivity characteristics, and spatial transmission characteristics. A center extraction method is proposed for improving the accuracy of the laser stripe center extraction based on image evaluation of Gaussian fitting structural similarity and analysis of the multiple source factors. First, according to the features of the gray distribution of the laser stripe, evaluation of the Gaussian fitting structural similarity is estimated to provide a threshold value for center compensation. Then using the relationships between the gray distribution of the laser stripe and the multiple source factors, a compensation method of center extraction is presented. Finally, measurement experiments for a large-scale aviation composite component are carried out. The experimental results for this specific implementation verify the feasibility of the proposed center extraction method and the improved accuracy for large-scale triangulation scanning measurements.
Li, Si; Yu, Dan-Ni; Ji, Fang-Ying; Zhou, Guang-Ming; He, Qiang
2012-11-01
The degradation of fluoranthene was researched by combined means of multiple fluorescence spectra, including emission, synchronous, excitation emission matrix (EEM), time-scan and photometry. The characteristics of the degradation and fluoranthene molecular changes within the degradation's process were also discussed according to the information about the degradation provided by all of the fluorescence spectra mentioned above. The equations of fluoranthene's degradation by potassium ferrate were obtained on the bases of fitting time-scan fluorescence curves at different time, and the degradation's kinetic was speculated accordingly. From the experimental results, multiple fluorescence data commonly reflected that it had same degradation rate at the same reaction time. t = 10 s, and the degradation rate is -55%, t = 25 s, -81%, t = 40 s, -91%. No new fluorescent characteristic was observed within every degradation' stage. The reaction stage during t < or = 20 s was crucial, in which the degradation process is closest to linear relationship. After this beginning stage, the linear relationship deviated gradually with the development of the degradation process. The degradation of fluoranthene by potassium ferrate was nearly in accord with the order of the first order reaction.
Multimodal frontostriatal connectivity underlies individual differences in self-esteem
Heatherton, Todd F.
2015-01-01
A heightened sense of self-esteem is associated with a reduced risk for several types of affective and psychiatric disorders, including depression, anxiety and eating disorders. However, little is known about how brain systems integrate self-referential processing and positive evaluation to give rise to these feelings. To address this, we combined diffusion tensor imaging (DTI) and functional magnetic resonance imaging (fMRI) to test how frontostriatal connectivity reflects long-term trait and short-term state aspects of self-esteem. Using DTI, we found individual variability in white matter structural integrity between the medial prefrontal cortex and the ventral striatum was related to trait measures of self-esteem, reflecting long-term stability of self-esteem maintenance. Using fMRI, we found that functional connectivity of these regions during positive self-evaluation was related to current feelings of self-esteem, reflecting short-term state self-esteem. These results provide convergent anatomical and functional evidence that self-esteem is related to the connectivity of frontostriatal circuits and suggest that feelings of self-worth may emerge from neural systems integrating information about the self with positive affect and reward. This information could potentially inform the etiology of diminished self-esteem underlying multiple psychiatric conditions and inform future studies of evaluative self-referential processing. PMID:24795440
Structured Antireflective Coating for Silicon at Submillimeter Frequencies
NASA Astrophysics Data System (ADS)
Padilla, Estefania
2018-01-01
Observations at millimeter and submillimeter wavelengths are useful for many astronomical studies, such as the polarization of the cosmic microwave background or the formation and evolution of galaxy clusters. In order to allow observations over a broad spectral bandwidth (approximatively from 70 to 420 GHz), innovative broadband anti-reflective (AR) optics must be utilized in submillimeter telescopes. Due to its low loss and high refractive index, silicon is a fine optical material at these frequencies, but an AR coating with multiple layers is required to maximize its transmission over a wide bandwidth. Structured multilayer AR coatings for silicon are currently being developed at Caltech and JPL. The development process includes the design of the structured layers with commercial electromagnetic simulation software, the fabrication by using deep reactive ion etching, and the test of the transmission and reflection of the patterned wafers. Geometrical 3D patterns have successfully been etched at the surface of the silicon wafers creating up to 2 layers with different effective refractive indices. The transmission and reflection of single AR layer wafers, measured between 75 and 330 GHz, are close to the simulation predictions. These results allow the development of new designs with 5 or 6 AR layers in order to improve the bandwidth and transmission of the silicon AR coatings.
Greene, Kathryn
2013-01-01
Adolescence is a time of increased risk-taking and recent intervention strategies have included adolescents planning or producing anti-risk messages for their peers. Although these projects may generate enthusiasm, we know little about message planning or production as a strategy for changing adolescent decision-making and behavior. The paper articulates the Theory of Active Involvement (TAI) to describe and explain the processes through which these active involvement interventions influence adolescents. TAI is based on social cognitive theory’s notion of self-regulation and examines multiple perspective-taking and activating the self-reflection processes. The theory specifically describes the process of cognitive changes experienced by participants in active involvement interventions. The sequence is conceptualized as starting when engagement with the intervention (arousal and involvement) produces skill and knowledge gains (immediate outcomes) that lead to reflection (perceived discrepancy) and then other cognitions (expectancies, norms, intentions), with the ultimate outcome being behavior change. Engaging the target audience in a process of self-reflection is conceptualized as the crucial ingredient for meaningful and sustainable change in cognitions and behavior. This paper provides valuable insight into how active involvement strategies function and how to best design these interventions, particularly those targeting adolescents. PMID:23980581
NASA Astrophysics Data System (ADS)
Sirikham, Adisorn; Zhao, Yifan; Mehnen, Jörn
2017-11-01
Thermography is a promising method for detecting subsurface defects, but accurate measurement of defect depth is still a big challenge because thermographic signals are typically corrupted by imaging noise and affected by 3D heat conduction. Existing methods based on numerical models are susceptible to signal noise and methods based on analytical models require rigorous assumptions that usually cannot be satisfied in practical applications. This paper presents a new method to improve the measurement accuracy of subsurface defect depth through determining the thermal wave reflection coefficient directly from observed data that is usually assumed to be pre-known. This target is achieved through introducing a new heat transfer model that includes multiple physical parameters to better describe the observed thermal behaviour in pulsed thermographic inspection. Numerical simulations are used to evaluate the performance of the proposed method against four selected state-of-the-art methods. Results show that the accuracy of depth measurement has been improved up to 10% when noise level is high and thermal wave reflection coefficients is low. The feasibility of the proposed method in real data is also validated through a case study on characterising flat-bottom holes in carbon fibre reinforced polymer (CFRP) laminates which has a wide application in various sectors of industry.
Polarization Phase-Compensating Coats for Metallic Mirrors
NASA Technical Reports Server (NTRS)
Balasubramanian, Kunjithapatham
2006-01-01
A method of compensating for or minimizing phase differences between orthogonal polarizations of light reflected from metallic mirrors at oblique incidence, as, for example, from weakly curved mirrors, is undergoing development. The method is intended to satisfy a need to maintain precise polarization phase relationships or minimum polarization differences needed for proper operation of telescopes and other scientific instruments that include single or multiple mirrors. The basic idea of the method is to optimally coat mirrors with thin engineered layers of materials that introduce phase differences that, as nearly precisely as possible, are opposite of the undesired phase differences arising in reflection with non-optimum coatings. Depending on the specific optical system, the method could involve any or all of the following elements: a) Optimization of a single coat on all the mirrors in the system. b) Optimization of a unique coat for each mirror such that the polarization phase effects of the coat on one mirror compensate, to an acceptably high degree over an acceptably wide wavelength range, for those of the coat on another mirror. c) Tapering the coat on each mirror. Optimization could involve the choice of a single dielectric coating material and its thickness, or design of a more complex coat consisting of multiple layers of different dielectric materials and possibly some metallic materials. Such designs and coatings are particularly significant and needed for obtaining very high quality of wavefront required in high-contrast imaging instruments such as the NASA Terrestrial Planet Finder Coronagraph.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Michels-Clark, Tara M.; Savici, Andrei T.; Lynch, Vickie E.
Evidence is mounting that potentially exploitable properties of technologically and chemically interesting crystalline materials are often attributable to local structure effects, which can be observed as modulated diffuse scattering (mDS) next to Bragg diffraction (BD). BD forms a regular sparse grid of intense discrete points in reciprocal space. Traditionally, the intensity of each Bragg peak is extracted by integration of each individual reflection first, followed by application of the required corrections. In contrast, mDS is weak and covers expansive volumes of reciprocal space close to, or between, Bragg reflections. For a representative measurement of the diffuse scattering, multiple sample orientationsmore » are generally required, where many points in reciprocal space are measured multiple times and the resulting data are combined. The common post-integration data reduction method is not optimal with regard to counting statistics. A general and inclusive data processing method is needed. In this contribution, a comprehensive data analysis approach is introduced to correct and merge the full volume of scattering data in a single step, while correctly accounting for the statistical weight of the individual measurements. Lastly, development of this new approach required the exploration of a data treatment and correction protocol that includes the entire collected reciprocal space volume, using neutron time-of-flight or wavelength-resolved data collected at TOPAZ at the Spallation Neutron Source at Oak Ridge National Laboratory.« less
Spencer, Monique E; Jain, Alka; Matteini, Amy; Beamer, Brock A; Wang, Nae-Yuh; Leng, Sean X; Punjabi, Naresh M; Walston, Jeremy D; Fedarko, Neal S
2010-08-01
Neopterin, a GTP metabolite expressed by macrophages, is a marker of immune activation. We hypothesize that levels of this serum marker alter with donor age, reflecting increased chronic immune activation in normal aging. In addition to age, we assessed gender, race, body mass index (BMI), and percentage of body fat (%fat) as potential covariates. Serum was obtained from 426 healthy participants whose age ranged from 18 to 87 years. Anthropometric measures included %fat and BMI. Neopterin concentrations were measured by competitive ELISA. The paired associations between neopterin and age, BMI, or %fat were analyzed by Spearman's correlation or by linear regression of log-transformed neopterin, whereas overall associations were modeled by multiple regression of log-transformed neopterin as a function of age, gender, race, BMI, %fat, and interaction terms. Across all participants, neopterin exhibited a positive association with age, BMI, and %fat. Multiple regression modeling of neopterin in women and men as a function of age, BMI, and race revealed that each covariate contributed significantly to neopterin values and that optimal modeling required an interaction term between race and BMI. The covariate %fat was highly correlated with BMI and could be substituted for BMI to yield similar regression coefficients. The association of age and gender with neopterin levels and their modification by race, BMI, or %fat reflect the biology underlying chronic immune activation and perhaps gender differences in disease incidence, morbidity, and mortality.
Trammel, E. Jamie; Carter, Sarah; Haby, Travis S.; Taylor, Jason J.
2018-01-01
Enhancing natural resource management has been a focus of landscape ecology since its inception, but numerous authors argue that landscape ecology has not yet been effective in achieving the underlying goal of planning and designing sustainable landscapes. We developed nine questions reflecting the application of fundamental research topics in landscape ecology to the landscape planning process and reviewed two recent landscape-scale plans in western North America for evidence of these concepts in plan decisions. Both plans considered multiple resources, uses, and values, including energy development, recreation, conservation, and protection of cultural and historic resources. We found that land use change and multiscale perspectives of resource uses and values were very often apparent in planning decisions. Pattern-process relationships, connectivity and fragmentation, ecosystem services, landscape history, and climate change were reflected less frequently. Landscape sustainability was considered only once in the 295 decisions reviewed, and outputs of landscape models were not referenced. We suggest six actionable opportunities for further integrating landscape ecology concepts into landscape planning efforts: 1) use landscape sustainability as an overarching goal, 2) adopt a broad ecosystem services framework, 3) explore the role of landscape history more comprehensively, 4) regularly consider and accommodate potential effects of climate change, 5) use landscape models to support plan decisions, and 6) promote a greater presence of landscape ecologists within agencies that manage large land bases and encourage active involvement in agency planning efforts. Together these actions may improve the defensibility, durability, and sustainability of landscape plan decisions.
Domestication of a Mesoamerican cultivated fruit tree, Spondias purpurea.
Miller, Allison; Schaal, Barbara
2005-09-06
Contemporary patterns of genetic variation in crops reflect historical processes associated with domestication, such as the geographic origin(s) of cultivated populations. Although significant progress has been made in identifying several global centers of domestication, few studies have addressed the issue of multiple origins of cultivated plant populations from different geographic regions within a domestication center. This study investigates the domestication history of jocote (Spondias purpurea), a Mesoamerican cultivated fruit tree. Sequences of the chloroplast spacer trnG-trnS were obtained for cultivated and wild S. purpurea trees, two sympatric taxa (Spondias mombin var. mombin and Spondias radlkoferi), and two outgroups (S. mombin var. globosa and Spondias testudinus). A phylogeographic approach was used and statistically significant associations of clades and geographical location were tested with a nested clade analysis. The sequences confirm that wild populations of S. purpurea are the likely progenitors of cultivated jocote trees. This study provides phylogeographic evidence of multiple domestications of this Mesoamerican cultivated fruit tree. Haplotypes detected in S. purpurea trees form two clusters, each of which includes alleles recovered in both cultivated and wild populations from distinct geographic regions. Cultivated S. purpurea populations have fewer unique trnG-trnS alleles than wild populations; however, five haplotypes were absent in the wild. The presence of unique alleles in cultivation may reflect contemporary extinction of the tropical dry forests of Mesoamerica. These data indicate that some agricultural habitats may be functioning as reservoirs of genetic variation in S. purpurea.
Michels-Clark, Tara M.; Savici, Andrei T.; Lynch, Vickie E.; ...
2016-03-01
Evidence is mounting that potentially exploitable properties of technologically and chemically interesting crystalline materials are often attributable to local structure effects, which can be observed as modulated diffuse scattering (mDS) next to Bragg diffraction (BD). BD forms a regular sparse grid of intense discrete points in reciprocal space. Traditionally, the intensity of each Bragg peak is extracted by integration of each individual reflection first, followed by application of the required corrections. In contrast, mDS is weak and covers expansive volumes of reciprocal space close to, or between, Bragg reflections. For a representative measurement of the diffuse scattering, multiple sample orientationsmore » are generally required, where many points in reciprocal space are measured multiple times and the resulting data are combined. The common post-integration data reduction method is not optimal with regard to counting statistics. A general and inclusive data processing method is needed. In this contribution, a comprehensive data analysis approach is introduced to correct and merge the full volume of scattering data in a single step, while correctly accounting for the statistical weight of the individual measurements. Lastly, development of this new approach required the exploration of a data treatment and correction protocol that includes the entire collected reciprocal space volume, using neutron time-of-flight or wavelength-resolved data collected at TOPAZ at the Spallation Neutron Source at Oak Ridge National Laboratory.« less