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Sample records for ab dor moving

  1. The AB Dor Moving Group: A Chemically Heterogeneous Kinematic Stream?

    NASA Astrophysics Data System (ADS)

    Barenfeld, Scott A.; Bubar, E. J.; Mamajek, E. E.; Young, P. A.

    2012-01-01

    The AB Dor Moving Group is the nearest kinematic group to the Sun. It consists of a "nucleus" of 10 comoving stars at distance 20 pc (Zuckerman et al. 2004), along with dozens of purported "stream" members spread out across the sky, with distances up to 140 pc away (Torres et al. 2008). We perform a kinematic and chemical analysis of a sample of 10 AB Dor "stream" members to test whether they constitute a physical stellar group. We use the NEMO Galactic kinematic code to investigate the orbits of the stream members, and perform a chemical abundance analysis using high resolution, high S/N spectra taken with the MIKE spectrograph on the Magellan Clay 6.5-m telescope. Using a chi-squared test with the measured abundances for 10 different elements (Fe, Na, Mg, Si, Al, Ca, Cr, Mn, Ni, and Ba), we find that only a few of the ten purported AB Dor stream members appear to constitute a statistically chemically homogeneous sample. Our orbit simulations show that some of the "stream" members were hundreds of pc from AB Dor 100 Myr ago, and hence were unlikely to have formed near the eponymous star. The lack of kinematic and chemical coherence among the stream sample suggests that the published lists of AB Dor moving group members are unlikely to represent the dispersed remnant of a single star formation episode. Our study does not rule out the physicality of the AB Dor "nucleus" identified by Zuckerman et al., which appears to be coeval with the Pleiades ( 120 Myr). We conclude that the AB Dor stream is dynamical in nature, likely containing stars from many different birth sites. This research was supported by NSF grant AST-1008908, an REU supplement, and funds from the School of Arts and Sciences at the University of Rochester.

  2. A KINE-CHEMICAL INVESTIGATION OF THE AB DOR MOVING GROUP 'STREAM'

    SciTech Connect

    Barenfeld, Scott A.; Bubar, Eric J.; Mamajek, Eric E.; Young, Patrick A.

    2013-03-20

    The AB Dor Moving Group consists of a 'nucleus' of {approx}10 stars at d {approx_equal} 20 pc, along with dozens of purported 'stream' members distributed across the sky. We perform a chemical and kinematic analysis of a subsample of AB Dor stream stars to test whether they constitute a physical stellar group. We use the NEMO Galactic kinematic code to investigate the orbits of the stream members, and perform a chemical abundance analysis using high resolution spectra taken with the Magellan Clay 6.5 m telescope. Using a {chi}{sup 2} test with the measured abundances for 10 different elements, we find that only half of the purported AB Dor stream members could possibly constitute a statistically chemically homogeneous sample. Some stream members with three-dimensional velocities were hundreds of parsecs from the AB Dor nucleus {approx}10{sup 8} yr ago, and hence were unlikely to share a common origin. We conclude that the published lists of AB Dor moving group stream members are unlikely to represent the dispersed remnant of a single star formation episode. A subsample of the stream stars appears to be both statistically chemically homogeneous and in the vicinity of the AB Dor nucleus at birth. Their mean metallicity is [Fe/H] = 0.02 {+-} 0.02 dex, which we consider representative for the AB Dor group. Finally, we report a strong lower limit on the age of the AB Dor nucleus of >110 Myr based on the pre-main sequence contraction times for K-type members which have reached the main sequence.

  3. WISEP J004701.06+680352.1: AN INTERMEDIATE SURFACE GRAVITY, DUSTY BROWN DWARF IN THE AB DOR MOVING GROUP

    SciTech Connect

    Gizis, John E.; Allers, Katelyn N.; Liu, Michael C.; Harris, Hugh C.; Faherty, Jacqueline K.; Burgasser, Adam J.; Kirkpatrick, J. Davy

    2015-02-01

    We present spectroscopy, astrometry, and photometry of the brown dwarf WISEP J004701.06+680352.1 (W0047+68), an unusually red field L dwarf at a distance of 12.2 ± 0.4 pc. The three-dimensional space motion identifies it as a member of the AB Dor Moving Group, an identification supported by our classification of W0047+68 as intermediate surface gravity (INT-G) using the Allers and Liu near-infrared classification system. This moving group membership implies near-solar metallicity, age ∼100-125 Myr, M ≈ 0.018 M {sub ☉}, and log g ≈ 4.5; the thick condensate clouds needed to explain the infrared spectrum are, therefore, a result of surface gravity that is lower than that of ordinary field brown dwarfs. From the observed luminosity and evolutionary model radius, we find T {sub eff} ≈ 1300 K, a temperature normally associated with early T dwarfs. Thick clouds are also used to explain the spectral properties of directly imaged giant planets, and we discuss the successes and challenges for such substellar models in matching the observed optical and infrared spectra. W0047+68 shows that cloud thickness is more sensitive to intermediate surface gravity than in most models. We also present a trigonometric parallax of the dusty L6 dwarf 2MASS J21481628+4003593. It lies at 8.060 ± 0.036 parsecs; its astrometry is consistent with the view that it is older and metal-rich.

  4. Brown Dwarfs in Young Moving Groups from Pan-STARRS1. I. AB Doradus

    NASA Astrophysics Data System (ADS)

    Aller, Kimberly M.; Liu, Michael C.; Magnier, Eugene A.; Best, William M. J.; Kotson, Michael C.; Burgett, William S.; Chambers, Kenneth C.; Hodapp, Klaus W.; Flewelling, Heather; Kaiser, Nick; Metcalf, Nigel; Tonry, John L.; Wainscoat, Richard J.; Waters, Christopher

    2016-04-01

    Substellar members of young (≲150 Myr) moving groups are valuable benchmarks to empirically define brown dwarf evolution with age and to study the low-mass end of the initial mass function. We have combined Pan-STARRS1 (PS1) proper motions with optical–IR photometry from PS1, Two Micron All Sky Survey (2MASS), and WISE to search for substellar members of the AB Dor Moving Group within ≈50 pc and with spectral types of late M to early L, corresponding to masses down to ≈30 MJup at the age of the group (≈125 Myr). Including both photometry and proper motions allows us to better select candidates by excluding field dwarfs whose colors are similar to young AB Dor Moving Group members. Our near-IR spectroscopy has identified six ultracool dwarfs (M6–L4 ≈30–100 MJup) with intermediate surface gravities (int-g) as candidate members of the AB Dor Moving Group. We find another two candidate members with spectra showing hints of youth but consistent with field gravities. We also find four field brown dwarfs unassociated with the AB Dor Moving Group, three of which have int-g gravity classification. While signatures of youth are present in the spectra of our ≈125 Myr objects, neither their J – K nor W1 – W2 colors are significantly redder than field dwarfs with the same spectral types, unlike younger ultracool dwarfs. We also determined PS1 parallaxes for eight of our candidates and one previously identified AB Dor Moving Group candidate. Although radial velocities (and parallaxes, for some) are still needed to fully assess membership, these new objects provide valuable insight into the spectral characteristics and evolution of young brown dwarfs.

  5. The Coronae of AB Dor and V471 Tau: Youth vs Tidal Spin-Up

    NASA Astrophysics Data System (ADS)

    García-Alvarez, D.; Drake, J. J.; Lin, L.; Kashyap, V.

    2004-01-01

    We report on an analysis of high resolution Chandra spectra of two stars with very similar spectral types and rotation rates but with very different evolutionary histories. AB Doradus is a young relatively bright (V=6.9) rapidly rotating (P=0.51d) late-type star (dK0-2) that is just evolving onto the main sequence. V471 Tau is a post-common envelope pre-cataclysmic binary system and is comprised of a cool main-sequence chromospherically active dwarf (dK2V=9.5) and a degenerate hot white dwarf in an orbit with a separation of only 3.4 R* and P=0.52d. Chandra HETGS spectra of AB Dor and LETGS spectra V471 Tau caught both objects in relatively quiescent non-flaring states and show them to have very similar X-ray spectra. Using a new technique based on the ratios of prominent lines of highly ionized Fe and resonance lines of He-like and H-like ions we have determined the temperature structure and chemical composition of the emitting plasma in both coronae. Both stars have coronae that are relatively Ne-rich and Fe-poor similar to the abundances found from high-resolution spectra of other active stars. We compare and constrast the two coronae in the context of outer atmosphere structure and the rich emerging pattern of coronal abundance anomalies.

  6. LIKELY MEMBERS OF THE {beta} PICTORIS AND AB DORADUS MOVING GROUPS IN THE NORTH

    SciTech Connect

    Schlieder, Joshua E.; Lepine, Sebastien; Simon, Michal E-mail: michal.simon@stonybrook.edu

    2012-10-01

    We present first results from follow-up of targets in the northern hemisphere {beta} Pictoris and AB Doradus moving group candidate list of Schlieder et al. We obtained high-resolution, near-infrared spectra of 27 candidate members to measure their radial velocities and confirm consistent group kinematics. We identify 15 candidates with consistent predicted and measured radial velocities, perform analyses of their six-dimensional (UVWXYZ) Galactic kinematics, and compare to known group member distributions. Based on these analyses, we propose that seven {beta} Pic and eight AB Dor candidates are likely new group members. Four of the likely new {beta} Pic stars are binaries, one a double-lined spectroscopic system. Three of the proposed AB Dor stars are binaries. Counting all binary components, we propose 22 likely members of these young, moving groups. The majority of the proposed members are M2 to M5 dwarfs, the earliest being of type K2. We also present preliminary parameters for the two new spectroscopic binaries identified in the data, the proposed {beta} Pic member and a rejected {beta} Pic candidate. Our candidate selection and follow-up has thus far identified more than 40 low-mass, likely members of these two moving groups. These stars provide a new sample of nearby, young targets for studies of local star formation, disks and exoplanets via direct imaging, and astrophysics in the low-mass regime.

  7. COOL YOUNG STARS IN THE NORTHERN HEMISPHERE: {beta} PICTORIS AND AB DORADUS MOVING GROUP CANDIDATES

    SciTech Connect

    Schlieder, Joshua E.; Simon, Michal; Lepine, Sebastien E-mail: schlieder@mpia-hd.mpg.de

    2012-04-15

    As part of our continuing effort to identify new, low-mass members of nearby, young moving groups (NYMGs), we present a list of young, low-mass candidates in the northern hemisphere. We used our proven proper-motion selection procedure and ROSAT X-ray and GALEX-UV activity indicators to identify 204 young stars as candidate members of the {beta} Pictoris and AB Doradus NYMGs. Definitive membership assignment of a given candidate will require a measurement of its radial velocity and distance. We present a simple system of indices to characterize the young candidates and help prioritize follow-up observations. New group members identified in this candidate list will be high priority targets for (1) exoplanet direct imaging searches, (2) the study of post-T-Tauri astrophysics, (3) understanding recent local star formation, and (4) the study of local galactic kinematics. Information available now allows us to identify eight likely new members in the list. Two of these, a late-K and an early-M dwarf, we find to be likely members of the {beta} Pic group. The other six stars are likely members of the AB Dor moving group. These include an M dwarf triple system, and three very cool objects that may be young brown dwarfs, making them the lowest-mass, isolated objects proposed in the AB Dor moving group to date.

  8. X-Ray Evidence for a Pole-dominated Corona on AB Dor

    NASA Astrophysics Data System (ADS)

    Drake, Jeremy J.; Chung, Sun Mi; Kashyap, Vinay L.; Garcia-Alvarez, David

    2015-03-01

    A fine analysis of spectral line widths and Doppler shifts employing Fourier transform and cross-correlation techniques has been applied to Chandra HETG spectra obtained in 1999 October of the rapidly rotating young star AB Doradus in order to investigate its coronal topology. The observation lasted 52.3 ks, covering 1.2 rotation periods. The X-ray light curve obtained from integrating the dispersed signal revealed a moderate intensity flare midway through the exposure in which the count rate increased sharply by about 50% and subsequently decayed over the next 10 ks. We find no significant Doppler shifts in the spectra or modulation of the light curve that could be attributed to rotation of dominant coronal structures at this epoch. Individual spectral line widths are statistically consistent with thermal broadening and formally require no rotational broadening, while the 1σ limit to rotational broadening corresponds to a compact corona restricted to latitudes <57°. Fourier analysis suggests a small amount of rotational broadening is present consistent with a corona restricted largely to the poles, and excludes models with surface rotational broadening or greater. These results present direct spectroscopic evidence that the dominant coronal activity on rapidly rotating active stars is associated with the dark polar spots commonly seen in photospheric Doppler images and support models in which these spots are of mixed magnetic polarity that forms closed loops.

  9. β Pictoris and AB Doradus Moving Groups: Likely New Low-mass Members

    NASA Astrophysics Data System (ADS)

    Schlieder, Joshua E.; Lépine, Sébastien; Simon, Michal

    2010-07-01

    We present results from our continuing program to identify new, low-mass, members of the nearby young moving groups (NYMGs) using a proper motion selection algorithm and various observational techniques. We have three goals: (1) to provide high priority targets for exoplanet searches by direct imaging, (2) to complete the census of the membership in the NYMGs down to ~0.1 M sun, and thus (3) provide a well-characterized sample of nearby (median distances at least twice as close as the Taurus and Ophiuchus star-forming regions), young (8-50 Myr) stars for detailed study of their physical properties and multiplicity. Our program proceeds as follows: we apply the selection algorithm to a proper motion catalog where initial selection cuts of candidate members are based on the mean motion of known NYMG members and the proper motions and photometric distances of the candidates. NYMG membership is investigated further using possible signs of youth, including Hα emission and X-ray flux, and then verified through radial velocity measurements. We identify TYC 1766-1431-1 (M3), TYC 1208-468-1 and 2 (K3), TYC 7558-655-1 (K5), and PM I04439+3723W and E (M3) as likely members of the β Pictoris moving group (BPMG) and TYC 1741-2117-1N and S (K7), TYC 1752-63-1 (K7), TYC 523-573-1 (K7), and TYC 4943-192-1 (M0) as likely members of the AB Doradus moving group (ABDMG). We also rule out the membership of several BPMG and ABDMG candidates. To date our program has identified 16 new NYMG members of spectral type K3 or later.

  10. {beta} PICTORIS AND AB DORADUS MOVING GROUPS: LIKELY NEW LOW-MASS MEMBERS

    SciTech Connect

    Schlieder, Joshua E.; Simon, Michal; Lepine, Sebastien E-mail: michal.simon@stonybrook.ed

    2010-07-15

    We present results from our continuing program to identify new, low-mass, members of the nearby young moving groups (NYMGs) using a proper motion selection algorithm and various observational techniques. We have three goals: (1) to provide high priority targets for exoplanet searches by direct imaging, (2) to complete the census of the membership in the NYMGs down to {approx}0.1 M{sub sun}, and thus (3) provide a well-characterized sample of nearby (median distances at least twice as close as the Taurus and Ophiuchus star-forming regions), young (8-50 Myr) stars for detailed study of their physical properties and multiplicity. Our program proceeds as follows: we apply the selection algorithm to a proper motion catalog where initial selection cuts of candidate members are based on the mean motion of known NYMG members and the proper motions and photometric distances of the candidates. NYMG membership is investigated further using possible signs of youth, including H{alpha} emission and X-ray flux, and then verified through radial velocity measurements. We identify TYC 1766-1431-1 (M3), TYC 1208-468-1 and 2 (K3), TYC 7558-655-1 (K5), and PM I04439+3723W and E (M3) as likely members of the {beta} Pictoris moving group (BPMG) and TYC 1741-2117-1N and S (K7), TYC 1752-63-1 (K7), TYC 523-573-1 (K7), and TYC 4943-192-1 (M0) as likely members of the AB Doradus moving group (ABDMG). We also rule out the membership of several BPMG and ABDMG candidates. To date our program has identified 16 new NYMG members of spectral type K3 or later.

  11. Characterizing the AB Doradus moving group via high-resolution spectroscopy and kinematic traceback

    SciTech Connect

    McCarthy, Kyle; Wilhelm, Ronald J.

    2014-10-01

    We present a detailed analysis of 10 proposed F and G members of the nearby, young moving group AB Doradus (ABD). Our sample was obtained using the 2.7 m telescope at the McDonald Observatory with the coude echelle spectrograph, achieving R ∼ 60,000 and signal-to-noise ratio ∼200. We derive spectroscopic T {sub eff}, log(g), [Fe/H], and microturbulance (v{sub t} ) using a bootstrap method of the TGVIT software resulting in typical errors of 33K in T {sub eff}, 0.08 dex in log(g), 0.03 dex in [Fe/H], and 0.13 km s{sup –1} in v{sub t} . Characterization of the ABD sample is performed in three ways: (1) chemical homogeneity, (2) kinematic traceback, and (3) isochrone fitting. We find the average metal abundance is [M/H] = –0.03 ± 0.06 with a traceback age of 125 Myr. Our stars were fit to three different evolutionary models and we found that the best match to our ABD sample is the YREC [M/H] = –0.1 model. In our sample of 10 stars, we identify 1 star that is a probable non-member, 3 enigmatic stars, and 6 stars with confirmed membership. We also present a list of chemically coherent stars from this study and the Barenfeld et al. study.

  12. Spectroscopic confirmation of M-dwarf candidate members of the Beta Pictoris and AB Doradus Moving Groups

    NASA Astrophysics Data System (ADS)

    Binks, A. S.; Jeffries, R. D.

    2016-01-01

    Optical spectroscopic observations are reported for 24 and 23, nearby, proper-motion-selected M-dwarf candidate members of the Beta Pictoris and AB Doradus moving groups (BPMG and ABDMG). Using kinematic criteria, the presence of both Hα emission and high X-ray-to-bolometric luminosity, and position in absolute colour-magnitude diagrams, 10 and 6 of these candidates are confirmed as likely members of the BPMG and ABDMG, respectively. Equivalent widths or upper limits for the Li I 6708 Å line are reported and the lithium depletion boundary (LDB) age of the BPMG is revisited. Whilst non-magnetic evolutionary models still yield an estimated age of 21 ± 4 Myr, models that incorporate magnetic inhibition of convection imply an older age of 24 ± 4 Myr. A similar systematic increase would be inferred if the stars were 25 per cent covered by dark magnetic starspots. Since young, convective M-dwarfs are magnetically active and do have starspots, we suggest that the original LDB age estimate is a lower limit. The LDB age of the ABDMG is still poorly constrained - non-magnetic evolutionary models suggest an age in the range 35-150 Myr, which could be significantly tightened by new measurements for existing candidate members.

  13. dsrAB-based analysis of sulphate-reducing bacteria in moving bed biofilm reactor (MBBR) wastewater treatment plants.

    PubMed

    Biswas, Kristi; Taylor, Michael W; Turner, Susan J

    2014-08-01

    Sulphate-reducing bacteria (SRB) are important members of the sulphur cycle in wastewater treatment plants (WWTPs). In this study, we investigate the diversity and activity of SRB within the developing and established biofilm of two moving bed biofilm reactor (MBBR) systems treating municipal wastewater in New Zealand. The larger of the two WWTPs (Moa Point) generates high levels of sulphide relative to the smaller Karori plant. Clone libraries of the dissimilatory (bi)sulphite reductase (dsrAB) genes and quantitative real-time PCR targeting dsrA transcripts were used to compare SRB communities between the two WWTPs. Desulfobulbus (35-53 % of total SRB sequences) and genera belonging to the family Desulfobacteraceae (27-41 %) dominated the SRB fraction of the developing biofilm on deployed plastic carriers at both sites, whereas Desulfovibrio and Desulfomicrobium were exclusively found at Moa Point. In contrast, the established biofilms from resident MBBR carriers were largely dominated by Desulfomonile tiedjei-like organisms (58-100 % of SRB sequences). The relative transcript abundance of dsrA genes (signifying active SRBs) increased with biofilm weight yet remained low overall, even in the mature biofilm stage. Our results indicate that although SRB are both present and active in the microbial community at both MBBR study sites, differences in the availability of sulphate may be contributing to the observed differences in sulphide production at these two plants. PMID:24788329

  14. Interpolating moving least-squares methods for fitting potential energy surfaces : computing high-density potential energy surface data from low-density ab initio data points.

    SciTech Connect

    Dawes, R.; Thompson, D. L.; Guo, Y.; Wagner, A. F.; Minkoff, M.; Chemistry; Univ. of Missouri-Columbia; Oklahoma State Univ.

    2007-05-11

    A highly accurate and efficient method for molecular global potential energy surface (PES) construction and fitting is demonstrated. An interpolating-moving-least-squares (IMLS)-based method is developed using low-density ab initio Hessian values to compute high-density PES parameters suitable for accurate and efficient PES representation. The method is automated and flexible so that a PES can be optimally generated for classical trajectories, spectroscopy, or other applications. Two important bottlenecks for fitting PESs are addressed. First, high accuracy is obtained using a minimal density of ab initio points, thus overcoming the bottleneck of ab initio point generation faced in applications of modified-Shepard-based methods. Second, high efficiency is also possible (suitable when a huge number of potential energy and gradient evaluations are required during a trajectory calculation). This overcomes the bottleneck in high-order IMLS-based methods, i.e., the high cost/accuracy ratio for potential energy evaluations. The result is a set of hybrid IMLS methods in which high-order IMLS is used with low-density ab initio Hessian data to compute a dense grid of points at which the energy, Hessian, or even high-order IMLS fitting parameters are stored. A series of hybrid methods is then possible as these data can be used for neural network fitting, modified-Shepard interpolation, or approximate IMLS. Results that are indicative of the accuracy, efficiency, and scalability are presented for one-dimensional model potentials as well as for three-dimensional (HCN) and six-dimensional (HOOH) molecular PESs

  15. Beclometasone oral--DOR BioPharma.

    PubMed

    2007-01-01

    orBec is an oral enteric-coated tablet formulation of the corticosteroid beclometasone, which has been developed by Enteron Pharmaceuticals, a subsidiary of Corporate Technology Development (now DOR BioPharma). orBec is being developed for the treatment of gastrointestinal graft-versus-host disease (GVHD) and an NDA has been filed in the US. DOR BioPharma has also filed an MAA in Europe for the same indication.orBec is designed to reduce the need for systemic immunosuppressive drugs, thereby improving the outcome of bone marrow and stem cell transplantation.DOR BioPharma may seek a marketing partner in the US and elsewhere for orBec in GVHD and will seek a partner for other potential indications of the drug.In December 2001, Corporate Technology Development was acquired by Endorex Corporation (now DOR BioPharma). In October 1998, Enteron Pharmaceuticals (DOR BioPharma) entered into an exclusive, worldwide, royalty bearing license agreement with George B. McDonald, MD, including the right to grant sublicenses, for the rights to the intellectual property and know-how relating to orBec. In January 2007, DOR BioPharma received $US3 million under a non-binding letter of intent from Sigma-Tau Pharmaceuticals. The agreement grants Sigma-Tau an exclusive right to negotiate terms and conditions for a possible business transaction or strategic alliance regarding orBec and potentially other DOR pipeline compounds until 1 March 2007. Under the terms of the agreement, Sigma-Tau purchased $US1 million of DOR's common stock, with an additional $US2 million paid in cash. If no agreement is reached by 1 March 2007, DOR will return the $US2 million to Sigma-Tau within 60 days. DOR BioPharma received an unsolicited proposal from Cell Therapeutics, Inc. to acquire DOR BioPharma in January 2007. Because of the non-binding agreement already signed with Sigma-Tau, DOR BioPharma's board of directors cannot consider Cell Therapeutics' merger proposal at this time. orBec has been filed for

  16. New Low-Mass Members of Nearby Young Moving Groups

    NASA Astrophysics Data System (ADS)

    Schlieder, Joshua; Simon, Michal; Rice, Emily; Lepine, Sebastien

    2012-08-01

    We are now ready to expand our program to identify new low-mass members of nearby young moving groups (NYMGs) to stars of mass ≤0.3 M_⊙. This is important to: (1) complete the census of low-mass stars near the Sun, (2) provide high priority targets for disk and exoplanet studies by direct imaging, and (3) provide a well- characterized sample of nearby, young stars for detailed study of their physical and kinematic properties. Our proven technique starts with a proper motion selection algorithm, proceeds to vet the sample for indicators of youth, and requires as its last step the measurement of candidate member radial velocities (RVs). So far, we have measured more than 100 candidate RVs using CSHELL on the NASA-IRTF and PHOENIX on Gemini-South, yielding more than 50 likely new moving group members. Here we propose to continue our RV follow-up of candidate NYMG members using PHOENIX on the KPNO 4m. We aim to measure RVs and determine spectral types of 23 faint (V≥15, H≥9), late-type (≥M4) candidates of the (beta) Pic (10 Myrs), AB Dor (70 Myrs), Tuc/Hor (30 Myrs), and TW Hydrae (8 Myrs) moving groups.

  17. Magnetic topology and prominence patterns on AB Doradus

    NASA Astrophysics Data System (ADS)

    Donati, J.-F.; Collier Cameron, A.; Hussain, G. A. J.; Semel, M.

    1999-01-01

    We report new Zeeman--Doppler imaging observations of the rapidly rotating young K0 dwarf AB Doradus, obtained with the Anglo-Australian Telescope in 1996 December. From such observations, simultaneous brightness and magnetic images of the stellar photosphere of AB Dor were reconstructed at three different epochs. The magnetic topology of AB Dor is found to be very complex, with at least 12 different radial field regions of opposite polarities located all around the star. Significant azimuthal field fluxes are also detected in the form of one negative polarity region close to the equator, a series of positive polarity patches at intermediate latitudes and an almost complete ring of negative polarity encircling the rotational pole at high latitudes. In particular, the azimuthal polarities we reconstruct are in very good agreement with those obtained by Donati & Cameron, confirming that this field component is directly related to the dynamo-generated large-scale toroidal magnetic structure. The triple polarity latitudinal pattern observed for this structure in the upper hemisphere of AB Dor indicates that the degree of the underlying large-scale poloidal structure in an axisymmetric spherical harmonics expansion is equal to or greater than five. It also strengthens the idea that the dynamo processes operating in AB Dor feature a non-solar component distributed throughout the convective zone. From the subtle distortion of successive brightness images, we can also confirm the surface differential rotation first measured on this star by Donati & Cameron in both sense and magnitude, with a pole rotating more slowly than the equator by about one part in 220. Finally, the rotation periods we measure for four prominences (from the recurrence rate of their spectral signatures in Balmer lines) confirm the presumption that such clouds are anchored at intermediate to high latitudes. The intrinsic variability of these prominences is not associated with any abrupt changes in the

  18. Low Mass Members in Nearby Young Moving Groups Revealed

    NASA Astrophysics Data System (ADS)

    Schlieder, Joshua; Simon, Michal; Rice, Emily; Lepine, Sebastien

    2010-08-01

    We are now ready to expand our program that identifies highly probable low-mass members of the nearby young moving groups (NYMGs) to stars of mass ~ 0.1 Msun. This is important 1) To provide high priority targets for exoplanet searches by direct imaging, 2) To complete the census of the membership in the NYMGs, and 3) To provide a well-characterized sample of nearby young stars for detailed study of their physical properties and multiplicity (the median distances of the (beta) Pic and AB Dor groups are ~ 35 pc with ages ~ 12 and 50 Myr respectively). Our proven technique starts with a proper motion selection algorithm, proceeds to vet the sample for indicators of youth, and requires as its last step the measurement of candidate member radial velocities (RVs). So far, we have obtained all RV measurements with the high resolution IR spectrometer at the NASA-IRTF and have reached the limits of its applicability. To identify probable new members in the south, and also those of the lowest mass, we need the sensitivity of PHOENIX at Gemini-S and NIRSPEC at Keck-II.

  19. Accurate radio and optical positions for the radio star HD 36705 (AB Doradus)

    NASA Technical Reports Server (NTRS)

    White, Graeme L.; Jauncey, David L.; Batty, Michael J.; Peters, W. L.; Gulkis, S.

    1988-01-01

    Arc-second position measurements of the active star HD 36705 (AB Dor) and of the variable radio source found nearby are presented. These measurements show that the radio source is clearly identified with HD 36705 and not with the nearby red-dwarf star Rst 137B.

  20. A Digital Library for Education: The PEN-DOR Project.

    ERIC Educational Resources Information Center

    Fullerton, Karen; Greenberg, Jane; McClure, Maureen; Rasmussen, Edie; Stewart, Darin

    1999-01-01

    Describes Pen-DOR (Pennsylvania Education Network Digital Object Repository), a digital library designed to provide K-12 educators with access to multimedia resources and tools to create new lesson plans and modify existing ones via the World Wide Web. Discusses design problems of a distributed, object-oriented database architecture and describes…

  1. A self-consistent, absolute isochronal age scale for young moving groups in the solar neighbourhood

    NASA Astrophysics Data System (ADS)

    Bell, Cameron P. M.; Mamajek, Eric E.; Naylor, Tim

    2015-11-01

    We present a self-consistent, absolute isochronal age scale for young ( ≲ 200 Myr), nearby ( ≲ 100 pc) moving groups in the solar neighbourhood based on homogeneous fitting of semi-empirical pre-main-sequence model isochrones using the τ2 maximum-likelihood fitting statistic of Naylor & Jeffries in the MV, V - J colour-magnitude diagram. The final adopted ages for the groups are as follows: 149^{+51}_{-19} {Myr} for the AB Dor moving group, 24 ± 3 Myr for the β Pic moving group (BPMG), 45^{+11}_{-7} {Myr} for the Carina association, 42^{+6}_{-4} {Myr} for the Columba association, 11 ± 3 Myr for the η Cha cluster, 45 ± 4 Myr for the Tucana-Horologium moving group (Tuc-Hor), 10 ± 3 Myr for the TW Hya association and 22^{+4}_{-3} {Myr} for the 32 Ori group. At this stage we are uncomfortable assigning a final, unambiguous age to the Argus association as our membership list for the association appears to suffer from a high level of contamination, and therefore it remains unclear whether these stars represent a single population of coeval stars. Our isochronal ages for both the BPMG and Tuc-Hor are consistent with recent lithium depletion boundary (LDB) ages, which unlike isochronal ages, are relatively insensitive to the choice of low-mass evolutionary models. This consistency between the isochronal and LDB ages instils confidence that our self-consistent, absolute age scale for young, nearby moving groups is robust, and hence we suggest that these ages be adopted for future studies of these groups. Software implementing the methods described in this study is available from http://www.astro.ex.ac.uk/people/timn/tau-squared/.

  2. A Pan-STARRS-1 Search for Substellar Young Moving Group Members

    NASA Astrophysics Data System (ADS)

    Aller, Kimberly Mei; Liu, Michael C.

    2015-08-01

    Young moving groups (YMGs) provide a valuable evolutionary link between ongoing star formation in molecular clouds (~1 Myr) and old field stars (>1 Gyr). Previous searches for YMG members based on optical surveys such as Hipparcos and the Palomar Sky Survey were insensitive to the lowest mass members (<0.5 MSun). However, recent surveys have begun to reveal the low-mass stellar and substellar members. These substellar YMG members are valuable benchmarks to empirically define brown dwarf evolution with age and to study the lowest mass end of the initial mass function. We have combined Pan-STARRS1 (PS1) proper motions with optical—IR photometry from PS1, 2MASS and WISE to perform a systematic search for substellar members down to ~30 MJup. PS1 is a unique resource because of its large area coverage (30,000 degrees2) and its far-red sensitivity. Also, PS1 provides high quality multi-epoch astrometry essential for distinguishing candidate YMG members from old field stars. We have spectroscopically confirmed the youth of several candidate substellar members of the AB Dor Moving Group. These new candidate members bridge the gap between the known low-mass stellar and planetary-mass members and provide valuable insight into the spectral characteristics and evolution of young brown dwarfs.

  3. A Pan-STARRS1 Search for Substellar Young Moving Group Members

    NASA Astrophysics Data System (ADS)

    Aller, Kimberly M.; Liu, Michael C.; Magnier, Eugene A.

    2016-01-01

    Young moving groups (YMGs) are coeval, comoving groups of stars which have migrated from their birthsites after formation. In the substellar regime, YMG members are key benchmarks to empirically define brown dwarf evolution with age and to study the lowest mass end of the initial mass function. We have combined Pan-STARRS1 (PS1) proper motions with optical+IR photometry from PS1, 2MASS and WISE to perform a large-scale (~30,000 deg2) systematic search for substellar members down to ~10 MJup . We have obtained near-IR spectroscopy of a large sample of ultracool candidate YMG members to assess their youth via gravity-sensitive absorption features. We have identified several new intermediate-gravity candidate members of the AB Dor Moving Group, potentially greatly expanding the substellar membership. These new candidate members bridge the gap between the known low-mass stellar and planetary-mass members and yield valuable insight into the spectral characteristics of young brown dwarfs.

  4. Remembering AB

    NASA Astrophysics Data System (ADS)

    Belyayev, S. T.

    2013-06-01

    In 1947 I became a second-year student at Moscow State University's Physics and Engineering Department, where a part of the week's classes were taught at base organizations. Our group's base was the future Kurchatov Institute, at that time known as the mysterious "Laboratory N^circ 2," and later as LIPAN. . Besides group lectures and practical work at the experimental laboratories, we also had access to the general seminars which Igor Vasilyevich Kurchatov tried to hold, with Leonid Vasilyevich Groshev filling in when he was absent. At the seminar, theorists spoke as welcome co-presenters and commentators. In 1949 I felt ready to approach A. B. Migdal to ask if I could transfer to his theoretical sector. In response, he suggested a number of simple qualitative problems, which I then successfully solved. (Incidentally, AB used the very same "introductory problems" for screening many generations of students.) So I wound up among AB's students. From 1952 on (for 10 years) I also served as an employee of the Migdal Sector. My memoirs here are mainly inspired by these years of constant communication with AB. After my departure for Novosibirsk in 1962, although our meetings still took place, they became occasional....

  5. Moving RNA moves RNA forward.

    PubMed

    Peng, Lina; Li, Yujiao; Zhang, Lan; Yu, Wenqiang

    2013-10-01

    Cell communication affects all aspects of cell structure and behavior, such as cell proliferation, differentiation, division, and coordination of various physiological functions. The moving RNA in plants and mammalian cells indicates that nucleic acid could be one of the various types of messengers for cell communication. The microvesicle is a critical pathway that mediates RNA moving and keeps moving RNA stable in body fluids. When moving miRNA enters the target cell, it functions by altering the gene expression profile and significantly inhibiting mRNA translation in recipient cells. Thus, moving RNA may act as a long-range modulator during development, organogenesis, and tumor metastasis. PMID:24008386

  6. [Voix d'Or, an audio tool to revive memories].

    PubMed

    Braunschweig, Lina

    2010-01-01

    Voix d'Or is an audio tool designed to awaken the affective memory of elderly people and particularly those suffering from Alzheimer's disease. Every month it offers new radio programmes to initiate or facilitate leisure and entertainment activities, memory workshops or provide the basis of quiet moments. The tool has a double objective: to procure well-being, boost the individual's self-esteem and recognise his/her history and to facilitate exchange and communication between the residents and the staff of a care home. PMID:21137493

  7. Dehydroepiandrosterone (DHEA) supplementation in diminished ovarian reserve (DOR)

    PubMed Central

    2011-01-01

    Background With infertility populations in the developed world rapidly aging, treatment of diminished ovarian reserve (DOR) assumes increasing clinical importance. Dehydroepiandrosterone (DHEA) has been reported to improve pregnancy chances with DOR, and is now utilized by approximately one third of all IVF centers world-wide. Increasing DHEA utilization and publication of a first prospectively randomized trial now warrants a systematic review. Methods PubMed, Cochrane and Ovid Medline were searched between 1995 and 2010 under the following strategy: [ and ]. Bibliographies of relevant publications were further explored for additional relevant citations. Since only one randomized study has been published, publications, independent of evidence levels and quality assessment, were reviewed. Results Current best available evidence suggests that DHEA improves ovarian function, increases pregnancy chances and, by reducing aneuploidy, lowers miscarriage rates. DHEA over time also appears to objectively improve ovarian reserve. Recent animal data support androgens in promoting preantral follicle growth and reduction in follicle atresia. Discussion Improvement of oocyte/embryo quality with DHEA supplementation potentially suggests a new concept of ovarian aging, where ovarian environments, but not oocytes themselves, age. DHEA may, thus, represent a first agent beneficially affecting aging ovarian environments. Others can be expected to follow. PMID:21586137

  8. Moving Minds

    ERIC Educational Resources Information Center

    Parker, Terry; Hiett, Sandra; Marley, Donna

    2006-01-01

    This paper explores and examines a case study based at Ivy Bank Business and Enterprise College, The Imperial War Museum North, and Liverpool John Moores University. This collaboration took place from November 2004 until February 2005 culminating in an exhibition of children's artwork as part of the "Moving Minds" project at the IWM North. This…

  9. Results of a search for γ Dor and δ SCT stars with the Kepler spacecraft

    SciTech Connect

    Bradley, P. A.; Miles, L. F.; Guzik, J. A.; Uytterhoeven, K.; Jackiewicz, J.; Kinemuchi, K.

    2015-02-01

    The light curves of 2768 stars with effective temperatures and surface gravities placing them near the gamma Doradus (γ Dor)/delta Scuti (δ Sct) instability region were observed as part of the Kepler Guest Observer program from Cycles 1 through 5. The light curves were analyzed in a uniform manner to search for γ Dor, δ Sct, and hybrid star pulsations. The γ Dor, δ Sct, and hybrid star pulsations extend asteroseismology to stars slightly more massive (1.4–2.5 M{sub ⊙}) than our Sun. We find 207 γ Dor, 84 δ Sct, and 32 hybrid candidate stars. Many of these stars are cooler than the red edge of the γ Dor instability strip as determined from ground-based observations made before Kepler. A few of our γ Dor candidate stars lie on the hot side of the ground-based γ Dor instability strip. The hybrid candidate stars cover the entire region between 6200 K and the blue edge of the ground-based δ Sct instability strip. None of our candidate stars are hotter than the hot edge of the ground-based δ Sct instability strip. Our discoveries, coupled with the work of others, show that Kepler has discovered over 2000 γ Dor, δ Sct, and hybrid star candidates in the 116 square degree Kepler field of view. We found relatively few variable stars fainter than magnitude 15, which may be because they are far enough away to lie between spiral arms in our Galaxy, where there would be fewer stars.

  10. Moving NMR

    NASA Astrophysics Data System (ADS)

    Blümich, Bernhard; Casanova, Federico; Danieli, Ernesto; Gong, Qingxia; Greferath, Marcus; Haber, Agnes; Kolz, Jürgen; Perlo, Juan

    2008-12-01

    Initiated by the use of NMR for well logging, portable NMR instruments are being developed for a variety of novel applications in materials testing and process analysis and control. Open sensors enable non-destructive testing of large objects, and small, cup-size magnets become available for high throughput analysis by NMR relaxation and spectroscopy. Some recent developments of mobile NMR are reviewed which delineate the direction into which portable NMR is moving.

  11. Further Optimization and Evaluation of Bioavailable, Mixed-Efficacy µ-Opioid Receptor (MOR) Agonists/δ-Opioid Receptor (DOR) Antagonists: Balancing MOR and DOR Affinities

    PubMed Central

    Harland, Aubrie A.; Yeomans, Larisa; Griggs, Nicholas W.; Anand, Jessica P.; Pogozheva, Irina D.; Jutkiewicz, Emily M.; Traynor, John R.; Mosberg, Henry I.

    2016-01-01

    In a previously described peptidomimetic series, we reported the development of bifunctional µ-opioid receptor (MOR) agonist and δ-opioid receptor (DOR) antagonist ligands with a lead compound that produced antinociception for 1 h after intraperitoneal administration in mice. In this paper, we expand on our original series by presenting two modifications, both of which were designed with the following objectives: 1) probing bioavailability and improving metabolic stability, 2) balancing affinities between MOR and DOR while reducing affinity and efficacy at the Κ-opioid receptor (KOR), and 3) improving in vivo efficacy. Here we establish that through N-acetylation of our original peptidomimetic series, we are able to improve DOR affinity and increase selectivity relative to KOR while maintaining the desired MOR agonist/DOR antagonist profile. From initial in vivo studies, one compound (14a) was found to produce dose-dependent antinociception after peripheral administration with an improved duration of action of longer than 3 h. PMID:26524472

  12. Further Optimization and Evaluation of Bioavailable, Mixed-Efficacy μ-Opioid Receptor (MOR) Agonists/δ-Opioid Receptor (DOR) Antagonists: Balancing MOR and DOR Affinities.

    PubMed

    Harland, Aubrie A; Yeomans, Larisa; Griggs, Nicholas W; Anand, Jessica P; Pogozheva, Irina D; Jutkiewicz, Emily M; Traynor, John R; Mosberg, Henry I

    2015-11-25

    In a previously described peptidomimetic series, we reported the development of bifunctional μ-opioid receptor (MOR) agonist and δ-opioid receptor (DOR) antagonist ligands with a lead compound that produced antinociception for 1 h after intraperitoneal administration in mice. In this paper, we expand on our original series by presenting two modifications, both of which were designed with the following objectives: (1) probing bioavailability and improving metabolic stability, (2) balancing affinities between MOR and DOR while reducing affinity and efficacy at the κ-opioid receptor (KOR), and (3) improving in vivo efficacy. Here, we establish that, through N-acetylation of our original peptidomimetic series, we are able to improve DOR affinity and increase selectivity relative to KOR while maintaining the desired MOR agonist/DOR antagonist profile. From initial in vivo studies, one compound (14a) was found to produce dose-dependent antinociception after peripheral administration with an improved duration of action of longer than 3 h. PMID:26524472

  13. Memories of AB

    NASA Astrophysics Data System (ADS)

    Vaks, V. G.

    2013-06-01

    I had the good fortune to be a student of A. B. Migdal - AB, as we called him in person or in his absence - and to work in the sector he headed at the Kurchatov Institute, along with his other students and my friends, including Vitya Galitsky, Spartak Belyayev and Tolya Larkin. I was especially close with AB in the second half of the 1950s, the years most important for my formation, and AB's contribution to this formation was very great. To this day, I've often quoted AB on various occasions, as it's hard to put things better or more precisely than he did; I tell friends stories heard from AB, because these stories enhance life as AB himself enhanced it; my daughter is named Tanya after AB's wife Tatyana Lvovna, and so on. In what follows, I'll recount a few episodes in my life in which AB played an important or decisive role, and then will share some other memories of AB...

  14. THE GEMINI/NICI PLANET-FINDING CAMPAIGN: THE FREQUENCY OF PLANETS AROUND YOUNG MOVING GROUP STARS

    SciTech Connect

    Biller, Beth A.; Ftaclas, Christ; Liu, Michael C.; Wahhaj, Zahed; Nielsen, Eric L.; Hayward, Thomas L.; Hartung, Markus; Chun, Mark; Clarke, Fraser; Thatte, Niranjan; Shkolnik, Evgenya L.; Reid, I. Neill; Boss, Alan; Lin, Douglas; Alencar, Silvia H. P.; De Gouveia Dal Pino, Elisabete; Gregorio-Hetem, Jane [Universidade de Sao Paulo, IAG and others

    2013-11-10

    We report results of a direct imaging survey for giant planets around 80 members of the β Pic, TW Hya, Tucana-Horologium, AB Dor, and Hercules-Lyra moving groups, observed as part of the Gemini/NICI Planet-Finding Campaign. For this sample, we obtained median contrasts of ΔH = 13.9 mag at 1'' in combined CH{sub 4} narrowband ADI+SDI mode and median contrasts of ΔH = 15.1 mag at 2'' in H-band ADI mode. We found numerous (>70) candidate companions in our survey images. Some of these candidates were rejected as common-proper motion companions using archival data; we reobserved with Near-Infrared Coronagraphic Imager (NICI) all other candidates that lay within 400 AU of the star and were not in dense stellar fields. The vast majority of candidate companions were confirmed as background objects from archival observations and/or dedicated NICI Campaign followup. Four co-moving companions of brown dwarf or stellar mass were discovered in this moving group sample: PZ Tel B (36 ± 6 M{sub Jup}, 16.4 ± 1.0 AU), CD–35 2722B (31 ± 8 M{sub Jup}, 67 ± 4 AU), HD 12894B (0.46 ± 0.08 M{sub ☉}, 15.7 ± 1.0 AU), and BD+07 1919C (0.20 ± 0.03 M{sub ☉}, 12.5 ± 1.4 AU). From a Bayesian analysis of the achieved H band ADI and ASDI contrasts, using power-law models of planet distributions and hot-start evolutionary models, we restrict the frequency of 1-20 M{sub Jup} companions at semi-major axes from 10-150 AU to <18% at a 95.4% confidence level using DUSTY models and to <6% at a 95.4% using COND models. Our results strongly constrain the frequency of planets within semi-major axes of 50 AU as well. We restrict the frequency of 1-20 M{sub Jup} companions at semi-major axes from 10-50 AU to <21% at a 95.4% confidence level using DUSTY models and to <7% at a 95.4% using COND models. This survey is the deepest search to date for giant planets around young moving group stars.

  15. Make time to move

    MedlinePlus

    Exercise - time to move; Weight loss - time to move; Obesity - time to move ... Getting regular exercise benefits your health in many ways: Strengthens your heart and lungs Lowers your risk for heart disease and ...

  16. Holocene sea level changes at the coast of dor, southeast mediterranean.

    PubMed

    Sneh, Y; Klein, M

    1984-11-16

    Geological, geomorphological, and archeological data of changes in sea level during the Holocene at the Mediterranean coast of Dor provide a eustatic curve of the region. This curve shows that sea level was approximately 2 meters below the present level 4000 years ago, rose to 1 meter below the present level 3000 years ago, and was 1 meter higher than the present level 1500 years ago. It then dropped to 1 meter below the present level about 800 years ago. PMID:17759891

  17. Omega-AB

    2007-05-01

    A hierarchical, modular modeling environment for hybrid simulations of sequential-modular, systems dynamics, discrete-event, and agent-based paradigms Omega-AB models contain a hierarchically-defined module tree that specifies the execution logic for the simulation, and a multi-network graph that defines the environment within which the simulation occurs. Modules are the fundamental buildinig blocks of an Omega-AB model and can define anything from a basic mathematical operation to a complex behavioral response model. Modules rely on the "plug-in" conceptmore » which allows developers to build independent module libraries that are gathered, linked, and instantiated by the Omega-AB engine at run time. Inter-module communication occurs through two complimentary systems: pull-based "ports" for general computation patterns and push-based "plugs" for event processing. The simulation environment is an abstract graph of nodes and links. Agents (module sub-trees headed up by an Agent module) reside at nodes and relate to their neighbors through typed links. To facilitate the construction and visualization of complex, interacting networks with dramatically different structure, Omega-AB provides a system for organizing the nodes into hierarchica trees that describe "slices" of the overall network.« less

  18. ABS plastic RPCs

    SciTech Connect

    Ables, E.; Bionta, R.; Olson, H.; Ott, L.; Parker, E.; Wright, D.; Wuest, C

    1996-02-01

    After investigating a number of materials, we discovered that an ABS plastic doped with a conducting polymer performs well as the resistive electrode in a narrow gap RPC (resistive plate chamber). Operating in the streamer mode, we find efficiencies of 90-96% with low noise and low strip multiplicities. We have also studied a variety of operating gases and found that a mixture containing SF{sub 6}, a non-ozone depleting gas, argon and isobutane gives good streamer mode performance, even with isobutane concentrations of 20% or less.

  19. Estimating Accurate Relative Spacecraft Angular Position from DSN VLBI Phases Using X-Band Telemetry or DOR Tones

    NASA Technical Reports Server (NTRS)

    Bagri, Durgadas S.; Majid, Walid

    2009-01-01

    At present spacecraft angular position with Deep Space Network (DSN) is determined using group delay estimates from very long baseline interferometer (VLBI) phase measurements employing differential one way ranging (DOR) tones. As an alternative to this approach, we propose estimating position of a spacecraft to half a fringe cycle accuracy using time variations between measured and calculated phases as the Earth rotates using DSN VLBI baseline(s). Combining fringe location of the target with the phase allows high accuracy for spacecraft angular position estimate. This can be achieved using telemetry signals of at least 4-8 MSamples/sec data rate or DOR tones.

  20. Ab initio infrared and Raman spectra

    NASA Astrophysics Data System (ADS)

    Fredkin, Donald R.; Komornicki, Andrew; White, Steven R.; Wilson, Kent R.

    1983-06-01

    mechanically, using gradient techniques step by step along a classical trajectory whose path is determined by these quantum forces. We believe the QFCT method to be a more practical ab initio route to spectral band contours for large molecules, clusters, and solutions, and it can be equally applied to equilibrium and nonequilibrium systems. It is pointed out that a similar ab initio QFCT molecular dynamic approach could be used to compute other types of spectra, e.g., electronic absorption, as well as other parameters such as transport properties and thermodynamic functions and their quantum corrections. For parameters not depending on momenta, a parallel ab initio Monte Carlo approach would use electronic energies and other parameters of interest generated quantum mechanically, and ``classical'' trial moves of the nuclei.

  1. Moving and Being Moved: Implications for Practice.

    ERIC Educational Resources Information Center

    Kretchmar, R. Scott

    2000-01-01

    Uses philosophical writings, a novel about baseball, and a nonfiction work on rowing to analyze levels of meaning in physical activity, showing why three popular methods for enhancing meaning have not succeeded and may have moved some students away from deeper levels of meaning. The paper suggests that using hints taken from the three books could…

  2. Plants on the Move

    ERIC Educational Resources Information Center

    Damonte, Kathleen

    2005-01-01

    Living things respond to a stimulus, which is a change in the surroundings. Some common stimuli are noises, smells, and things the people see or feel, such as a change in temperature. Animals often respond to a stimulus by moving. Because plants can't move around in the same way animals do, plants have to respond in a different way. Plants can…

  3. Moving? A Relocation Guide.

    ERIC Educational Resources Information Center

    Rackliffe, Gary; Pearson, Nancy

    This guide answers questions for high school graduates moving away from home for the first time. The question and answer format begins with reasons for moving and offers ways of finding information about a new town before leaving, meeting people, and fighting homesickness and indecision. Practical advice is presented on money management and…

  4. Basal and morphine-evoked dopaminergic neurotransmission in the nucleus accumbens of MOR- and DOR-knockout mice.

    PubMed

    Chefer, Vladimir I; Kieffer, Brigitte L; Shippenberg, Toni S

    2003-10-01

    Conventional and no net flux microdialysis were used to quantify basal and morphine-induced extracellular dopamine (DA) levels and the basal extraction fraction, which provides an estimate of the rate of DA uptake, in the nucleus accumbens (NAc) of wild-type mice and those with a constitutive deletion of mu (MOR)- or delta (DOR)-opioid receptors. Locomotor activity was assessed in these same animals. No difference between genotypes in basal dialysate DA levels was seen. No net flux studies revealed significant decreases in the DA extraction fraction in both MOR- and DOR-knockout mice, indicating decreased basal DA uptake in both genotypes. Extracellular DA, however, was unchanged. Because extracellular neurotransmitter levels are determined by the dynamics of both release and uptake, these findings provide suggestive evidence that basal DA release is decreased in mutant mice. Systemic administration of morphine significantly increased locomotor activity and dialysate DA levels in wild-type mice. MOR-knockout mice failed to exhibit a behavioural response to morphine. The ability of morphine to increase DA levels, however, was reduced but not prevented. No alteration in the effects of morphine was observed in DOR-knockout mice. These data provide genetic evidence for the existence of tonically active MOR and DOR systems that modulate basal DA neurotransmission in the NAc. Furthermore, they demonstrate that in contrast to the locomotor-activating effects of morphine, a small component of morphine-evoked DA release occurs independently of MOR activation. PMID:14622224

  5. Embodied affectivity: on moving and being moved

    PubMed Central

    Fuchs, Thomas; Koch, Sabine C.

    2014-01-01

    There is a growing body of research indicating that bodily sensation and behavior strongly influences one's emotional reaction toward certain situations or objects. On this background, a framework model of embodied affectivity1 is suggested: we regard emotions as resulting from the circular interaction between affective qualities or affordances in the environment and the subject's bodily resonance, be it in the form of sensations, postures, expressive movements or movement tendencies. Motion and emotion are thus intrinsically connected: one is moved by movement (perception; impression; affection2) and moved to move (action; expression; e-motion). Through its resonance, the body functions as a medium of emotional perception: it colors or charges self-experience and the environment with affective valences while it remains itself in the background of one's own awareness. This model is then applied to emotional social understanding or interaffectivity which is regarded as an intertwinement of two cycles of embodied affectivity, thus continuously modifying each partner's affective affordances and bodily resonance. We conclude with considerations of how embodied affectivity is altered in psychopathology and can be addressed in psychotherapy of the embodied self. PMID:24936191

  6. Embodied affectivity: on moving and being moved.

    PubMed

    Fuchs, Thomas; Koch, Sabine C

    2014-01-01

    There is a growing body of research indicating that bodily sensation and behavior strongly influences one's emotional reaction toward certain situations or objects. On this background, a framework model of embodied affectivity is suggested: we regard emotions as resulting from the circular interaction between affective qualities or affordances in the environment and the subject's bodily resonance, be it in the form of sensations, postures, expressive movements or movement tendencies. Motion and emotion are thus intrinsically connected: one is moved by movement (perception; impression; affection) and moved to move (action; expression; e-motion). Through its resonance, the body functions as a medium of emotional perception: it colors or charges self-experience and the environment with affective valences while it remains itself in the background of one's own awareness. This model is then applied to emotional social understanding or interaffectivity which is regarded as an intertwinement of two cycles of embodied affectivity, thus continuously modifying each partner's affective affordances and bodily resonance. We conclude with considerations of how embodied affectivity is altered in psychopathology and can be addressed in psychotherapy of the embodied self. PMID:24936191

  7. Changes in gene expression of DOR and other thyroid hormone receptors in rat liver during acute-phase response

    PubMed Central

    Baumgartner, Bernhard G.; Naz, Naila; Sheikh, Nadeem; Moriconi, Federico; Ramadori, Giuliano

    2010-01-01

    Non-thyroidal illness is characterized by low tri-iodothyronine (T3) serum level under acute-phase conditions. We studied hepatic gene expression of the newly identified thyroid hormone receptor (TR) cofactor DOR/TP53INP2 together with TRs in a rat model of aseptic abscesses induced by injecting intramuscular turpentine-oil into each hind limb. A fast (4-6 h) decrease in the serum level of free thyroxine and free T3 was observed. By immunohistology, abundant DOR protein expression was detected in the nuclei of hepatocytes and ED-1+ (mononuclear phagocytes), CK-19+ (biliary cells), and SMA+ (mesenchymal cells of the portal tract) cells. DOR signal was reduced with a minimum at 6-12 h after the acute-phase reaction (APR). Immunohistology also showed a similar pattern of protein expression in TRα1 but without a significant change during APR. Transcripts specific for DOR, nuclear receptor co-repressor 1 (NCoR-1), and TRβ1 were down-regulated with a minimum at 6-12 h, whereas expression for TRα1 and TRα2 was slightly and significantly up-regulated, respectively, with a maximum at 24 h after APR was initiated. In cultured hepatocytes, acute-phase cytokines interleukin-1β (IL-1β) and IL-6 down-regulated DOR and TRβ1 at the mRNA level. Moreover, gene expression of DOR and TRs (TRα1, TRα2, and TRβ1) was up-regulated in hepatocytes by adding T3 to the culture medium; this up-regulation was almost completely blocked by treating the cells with IL-6. Thus, TRβ1, NCoR-1, and the recently identified DOR/TP53INP2 are abundantly expressed and down-regulated in liver cells during APR. Their down-regulation is attributable to the decreased serum level of thyroid hormones and most probably also to the direct action of the main acute-phase cytokines. PMID:20949361

  8. Identification of the key regulating genes of diminished ovarian reserve (DOR) by network and gene ontology analysis.

    PubMed

    Pashaiasl, Maryam; Ebrahimi, Mansour; Ebrahimie, Esmaeil

    2016-09-01

    Diminished ovarian reserve (DOR) is one of the reasons for infertility that not only affects both older and young women. Ovarian reserve assessment can be used as a new prognostic tool for infertility treatment decision making. Here, up- and down-regulated gene expression profiles of granulosa cells were analysed to generate a putative interaction map of the involved genes. In addition, gene ontology (GO) analysis was used to get insight intol the biological processes and molecular functions of involved proteins in DOR. Eleven up-regulated genes and nine down-regulated genes were identified and assessed by constructing interaction networks based on their biological processes. PTGS2, CTGF, LHCGR, CITED, SOCS2, STAR and FSTL3 were the key nodes in the up-regulated networks, while the IGF2, AMH, GREM, and FOXC1 proteins were key in the down-regulated networks. MIRN101-1, MIRN153-1 and MIRN194-1 inhibited the expression of SOCS2, while CSH1 and BMP2 positively regulated IGF1 and IGF2. Ossification, ovarian follicle development, vasculogenesis, sequence-specific DNA binding transcription factor activity, and golgi apparatus are the major differential groups between up-regulated and down-regulated genes in DOR. Meta-analysis of publicly available transcriptomic data highlighted the high coexpression of CTGF, connective tissue growth factor, with the other key regulators of DOR. CTGF is involved in organ senescence and focal adhesion pathway according to GO analysis. These findings provide a comprehensive system biology based insight into the aetiology of DOR through network and gene ontology analyses. PMID:27324248

  9. Moving target exploitation

    NASA Astrophysics Data System (ADS)

    Johnson, Bruce L.; Grayson, Timothy P.

    1998-08-01

    The understanding of maneuvering forces is invaluable to the warfighter, as it enhances understanding of enemy force structure and disposition, provides cues to potential enemy actions, and expedites targeting of time critical targets. Airborne ground moving target indicator (GMTI) radars are a class of highly-effective, all-weather, wide-area senors that aid in the surveillance of these moving ground vehicles. Unfortunately conventional GMTI radars are incapable of identifying individual vehicles, and techniques for exploiting information imbedded within GMTI radar reports are limited. The Defense Advanced Research Projects Agency (DARPA) Moving Target Exploitation (MTE) program is working to mitigate these deficiencies by developing, integrating, and evaluating a suite of automated and semi-automated technologies to classify moving targets and units, and to provide indications of their activities. These techniques include: aid in the interpretation of GMTI data to provide moving force structure analysis, automatic tracking of thousands of moving ground vehicles, 1-D target classification based upon high-range- resolution (HRR) radar profiles, and 2-D target classification based upon moving target imaging (MTIm) synthetic aperture radar (SAR). This paper shall present the MTE concept and motivation and provide an overview of results to date.

  10. Amplitude Variability in gamma Dor and delta Sct Stars Observed by Kepler

    SciTech Connect

    Guzik, Joyce Ann; Kosak, Mary Katherine; Bradley, Paul Andrew; Jackiewicz, Jason

    2015-08-17

    The NASA Kepler spacecraft data revealed a large number of new multimode nonradially pulsating gamma Dor and delta Sct variable stars. The Kepler high-precision long time-series photometry makes it possible to study amplitude variations of the frequencies, and recent literature on amplitude and frequency variations in nonradially pulsating variables is summarized. Several methods are applied to study amplitude variability in about a dozen gamma Doradus or delta Scuti candidate variable stars observed for several quarters as part of the Kepler Guest Observer program. The magnitude and timescale of the amplitude variations are discussed, along with the presence or absence of correlations between amplitude variations for different frequencies of a given star. Proposed causes of amplitude spectrum variability that will require further investigation are also discussed.

  11. Study of the period changes in SW Dor, an RR Lyrae type star with Blazhko effect

    NASA Astrophysics Data System (ADS)

    Berdnikov, L. N.; Kniazev, A. Y.; Dambis, A. K.; Kravtsov, V. V.; Sefako, R.

    2016-09-01

    In 2012-2014 we acquired 1569 CCD BVIc frames for the RR Lyrae type variable SW Dor with the 76-cm telescope of the South African Astronomical Observatory (SAAO) and 1-m telescopes of Las Cumbres Observatory Global Telescope network (LCOGT). Our observations showed a large scatter in the resulting phased light curve, especially near maximum brightness, which allowed us to reveal the Blazhko effect with a period of ˜80.9d. To study the pulsation period changes, we used all the available observations including the 1299 magnitude estimates from the digitized plate library of Harvard University (the DASCH project), which allowed us to construct the O-C diagram spanning a 125-year long time interval and discover for the first time at least three abrupt changes of the pulsation period.

  12. The Anon(R132) Cluster in 30Dor -- the Poor Older Sibling of R136

    NASA Astrophysics Data System (ADS)

    Grebel, E. K.; Chu, Y.-H.; Bomans, D. J.; Points, S. D.

    1996-05-01

    At a distance of 50 kpc, 30Doradus provides a unique opportunity to study the detailed star formation history in a giant starburst region. 30Dor contains two clusters: the famous, compact, young R136 cluster at its core, and an anonymous, poorer, older cluster ~ 3' to the northwest. We call this anonymous cluster Anon(R132), since R132 is only 20'' from the cluster center. While the R136 cluster has been the focus of numerous studies, the Anon(R132) cluster has been neglected. Thus, our understanding of the starburst in 30 Dor is severely limited. We have obtained HST WFPC2 images of the Anon(R132) cluster in the F336W, F555W, F814W, and F656N filters, roughly corresponding to the U, V, I, and Hα bands. The photometry reaches V ~ 24 mag and spans at least 12 mag. The color-magnitude diagrams show an extended main sequence with a small number of supergiants. Analysis of these data will allow us to examine the stellar content and derive the age of Anon(R132). The Hα and continuum images allow us to identify Be candidates and potential pre-main sequence stars. We will examine the slope and low-mass end of the initial mass function (IMF) of Anon(R132), and compare it with R136. Furthermore, we will use the derived IMF to estimate the stellar wind and supernova energy input into the ambient interstellar medium. This study will significantly enhance our understanding of cluster formation in starbursts.

  13. KIC 9851142: A binary star with total eclipses and γ Dor pulsations

    NASA Astrophysics Data System (ADS)

    Çakırlı, Ö.

    2015-07-01

    KIC 9851142 (V2094 Cyg, HD 188854) is an eccentric eclipsing binary with an orbital period of Porb = 8.4854 d, exhibiting millimagnitude (mmag) amplitude pulsations on time scales of a few days. I present the results of the analysis of high-resolution spectroscopic data and Kepler long and short cadence photometry. The iterative combination of spectral classification by atmospheric analysis, radial velocity and eclipse timing variation studies, separation of pulsational features of the light curve, and binary light curve analysis led to the accurate determination of the fundamental stellar parameters and the comparison with evolutionary models strict constraints on the system age. I found that the binary is composed of two main sequence stars with an age of 0.75 ± 0.21 Gyr, having masses, radii and temperatures of M1 = 1.79 ± 0.11 M⊙ , R1 = 2.47 ± 0.07R⊙,Teff1 = 7250 ± 480 K for the primary, and M2 = 0.83 ± 0.12M⊙ , R2 = 0.67 ± 0.05R⊙,Teff2 = 5050 ± 650 K for the secondary. Multiple frequency analyses techniques were applied to the light residuals after subtracting the synthetic eclipsing curve from the Kepler data. This revealed that the primary component of KIC 9851142 is a γ Dor type pulsating star, exhibiting five pulsation frequencies in the range of 0.6-1.95 d-1 with amplitudes of 0.29-6.72 mmag and pulsation constants of 0.24-0.27 d. The analysis of the eclipse timing variations revealed preliminary apsidal motion with a period of Papseobs = 240 ± 29 y. Only six eclipsing binaries have been known to contain γ Dor pulsating components and, therefore, KIC 9851142 will be an important test-bed for examining these exceptional and interesting objects.

  14. Are Your Bowels Moving?

    MedlinePlus

    ... how to prevent accidents in the future. continue Diarrhea Diarrhea means you have to move your bowels often, ... eat or if you're taking certain medicines. Diarrhea also can happen when you don't wash ...

  15. Moving Objects Updating

    NASA Astrophysics Data System (ADS)

    Chen, Jidong; Meng, Xiaofeng

    In moving objects applications, large numbers of locations can be sampled by sensors or GPS periodically, then sent from moving clients to the server and stored in a database. Therefore, continuously maintaining in a database the current locations of moving objects by using a tracking technique becomes very important. The key issue is minimizing the number of updates, while providing precise locations for query results. In this chapter, we will introduce some underlying location update methods. Then, we describe two location update strategies in detail, which can improve the performance. One is the proactive location update strategy, which predicts the movement of moving objects to lower the update frequency; the other is the group location update strategy, which groups the objects to minimize the total number of objects reporting their locations.

  16. A moving overlay shrinks the attentional blink.

    PubMed

    Chua, Fook K

    2015-01-01

    This report describes a study examining the effects of overlaying a veil of spots on the letters in a central rapid serial visual presentation stream. Observers identified two target letters (T1 and T2, respectively) embedded in a stream of distractor letters printed in a different color. In Experiment 1, the attentional blink (AB) diminished when a different overlay veiled each letter, such that the spots appeared to move as the letters changed. Experiment 2 concerned whether the performance enhancement occurred because the overlay hampered processing of the lag 1 distractor, thus weakening the distractor's interference with T1. Experiment 3 focused on how changing the overlay at or around T1 affected the AB. The attention disengagement hypothesis was proposed to explain the common theme in the results-that performance was only enhanced when different overlays were applied to the T1 and lag 1 frames. The claim is that the AB reflects a failure of prompt attentional disengagement from T1, which, in turn, delays reengagement when T2 appears shortly thereafter. When T1's disappearance is accompanied by an overlay change, the perceptual system gets an additional cue signaling that the visual scene has changed, thereby inducing attentional disengagement. Apart from facilitating prompt reengagement at the next target, earlier disengagement also improves target recovery by excluding features of the trailing item, likely to be a distractor, from working memory. PMID:25245077

  17. Nanoparticules d'or: De l'imagerie par resonance magnetique a la radiosensibilisation

    NASA Astrophysics Data System (ADS)

    Hebert, Etienne M.

    Cette thèse approfondit l'étude de nanoparticules d'or de 5 nm de diamètre recouvertes de diamideéthanethioldiethylènetriaminepentacétate de gadolinium (DTDTPA:Gd), un agent de contraste pour l'imagerie par résonance magnétique (IRM). En guise de ciblage passif, la taille des nanoparticules a été contrôlée afin d'utiliser le réseau de néovaisseaux poreux et perméable des tumeurs. De plus les tumeurs ont un drainage lymphatique déficient qui permet aux nanoparticules de demeurer plus longtemps dans le milieu interstitiel de la tumeur. Les expériences ont été effectuées sur des souris Balb/c femelles portant des tumeurs MC7-L1. La concentration de nanoparticules a pu être mesurée à l'IRM in vivo. La concentration maximale se retrouvait à la fin de l'infusion de 10 min. La concentration s'élevait à 0.3 mM dans la tumeur et de 0.12 mM dans le muscle environnant. Les nanoparticules étaient éliminées avec une demi-vie de 22 min pour les tumeurs et de 20 min pour le muscle environnant. Les nanoparticules ont été fonctionnalisées avec le peptide Tat afin de leur conférer des propriétés de ciblage actif La rétention de ces nanoparticules a ainsi été augmentée de 1600 %, passant d'une demi-vie d'élimination de 22 min à 350 min. La survie des souris a été mesurée à l'aide de courbes Kaplan-Meier et d'un modèle mathématique évalue l'efficacité de traitements. Le modèle nous permet, à l'aide de la vitesse de croissance des tumeurs et de l'efficacité des traitements, de calculer la courbe de survie des spécimens. Un effet antagoniste a été observé au lieu de l'effet synergétique attendu entre une infusion de Au@DTDTPA:Gd et l'irradiation aux rayons X. L'absence d'effet synergétique a été attribuée à l'épaisseur du recouvrement de DTDTPA:Gd qui fait écran aux électrons produits par l'or. De plus, le moyen d'ancrage du recouvrement utilise des thiols qui peuvent s'avérer être des capteurs de radicaux. De plus

  18. The Gemini/NICI Planet-Finding Campaign: The Frequency of Planets around Young Moving Group Stars

    NASA Astrophysics Data System (ADS)

    Biller, Beth A.; Liu, Michael C.; Wahhaj, Zahed; Nielsen, Eric L.; Hayward, Thomas L.; Males, Jared R.; Skemer, Andrew; Close, Laird M.; Chun, Mark; Ftaclas, Christ; Clarke, Fraser; Thatte, Niranjan; Shkolnik, Evgenya L.; Reid, I. Neill; Hartung, Markus; Boss, Alan; Lin, Douglas; Alencar, Silvia H. P.; de Gouveia Dal Pino, Elisabete; Gregorio-Hetem, Jane; Toomey, Douglas

    2013-11-01

    We report results of a direct imaging survey for giant planets around 80 members of the β Pic, TW Hya, Tucana-Horologium, AB Dor, and Hercules-Lyra moving groups, observed as part of the Gemini/NICI Planet-Finding Campaign. For this sample, we obtained median contrasts of ΔH = 13.9 mag at 1'' in combined CH4 narrowband ADI+SDI mode and median contrasts of ΔH = 15.1 mag at 2'' in H-band ADI mode. We found numerous (>70) candidate companions in our survey images. Some of these candidates were rejected as common-proper motion companions using archival data; we reobserved with Near-Infrared Coronagraphic Imager (NICI) all other candidates that lay within 400 AU of the star and were not in dense stellar fields. The vast majority of candidate companions were confirmed as background objects from archival observations and/or dedicated NICI Campaign followup. Four co-moving companions of brown dwarf or stellar mass were discovered in this moving group sample: PZ Tel B (36 ± 6 M Jup, 16.4 ± 1.0 AU), CD-35 2722B (31 ± 8 M Jup, 67 ± 4 AU), HD 12894B (0.46 ± 0.08 M ⊙, 15.7 ± 1.0 AU), and BD+07 1919C (0.20 ± 0.03 M ⊙, 12.5 ± 1.4 AU). From a Bayesian analysis of the achieved H band ADI and ASDI contrasts, using power-law models of planet distributions and hot-start evolutionary models, we restrict the frequency of 1-20 M Jup companions at semi-major axes from 10-150 AU to <18% at a 95.4% confidence level using DUSTY models and to <6% at a 95.4% using COND models. Our results strongly constrain the frequency of planets within semi-major axes of 50 AU as well. We restrict the frequency of 1-20 M Jup companions at semi-major axes from 10-50 AU to <21% at a 95.4% confidence level using DUSTY models and to <7% at a 95.4% using COND models. This survey is the deepest search to date for giant planets around young moving group stars. Based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc

  19. Moving up in industry.

    PubMed

    Covell, Charlotte

    2016-01-23

    Charlotte Covell is commercial business manager at Virbac UK, a role that gives her responsibility for the company's sales to corporate practices, some buying groups and internet pharmacies. She began her career as a veterinary nurse, but moved into industry and now has a role in senior business management. PMID:26795866

  20. Let's Keep Moving!

    ERIC Educational Resources Information Center

    Obama, Michelle

    2012-01-01

    First Lady Michelle Obama lauds educators for following the lead of her Let's Move! program and taking action to curtail childhood obesity. The battle to make children healthier is being waged on a number of fronts by food companies, restaurants and schools. Progress has been made, she says, but more is needed.

  1. Who Moved the Lighthouse?

    ERIC Educational Resources Information Center

    Keim, William A.

    1991-01-01

    Traces the early development of the National Council on Community Services, pointing to important changes in the focus of the council since 1968. Identifies major figures in the movement. Opposes the move toward a more stylized academic existence for community services designed to meet institutional rather than community needs. (DMM)

  2. Who Moved the Lighthouse?

    ERIC Educational Resources Information Center

    Keim, William A.

    1982-01-01

    Traces the early development of the National Council on Community Services and Continuing Education from the creation of the National Council on Community Services in 1968. Opposes the move toward a more stylized academic existence for community services designed to meet institutional rather than community needs. (DMM)

  3. A Moving Tale

    ERIC Educational Resources Information Center

    Science Teacher, 2005

    2005-01-01

    Massachusetts Institute of Technology (MIT) mathematicians have discovered how certain insects can climb what to them are steep, slippery slopes in the water's surface without moving their limbs, and do it at high speed. Welcome to the world of the tiny creatures that live on the surface of ponds, lakes, and other standing bodies of water. For the…

  4. FREEDOM TO MOVE.

    ERIC Educational Resources Information Center

    CARPENTER, ETHELOUISE; SHIPLEY, FERNE

    PLAY WHICH INVOLVES NATURAL MOVEMENT HELPS THE CHILD TO LEARN ABOUT THE PROPERTIES OF MATTER AND ABOUT HIMSELF. AN EXPANSIVE AND VERSATILE USE OF SPACE FOR LIVING INCREASES WITH EXPLORATION. FREEDOM TO MOVE IS INTELLECTUAL AND EMOTIONAL, AS WELL AS PHYSICAL. NEW EXPERIENCES ARISING OUT OF CURIOSITY AND INTERACTION WITH HIS OWN FAMILY AND OTHER…

  5. Making Images That Move

    ERIC Educational Resources Information Center

    Rennie, Richard

    2015-01-01

    The history of the moving image (the cinema) is well documented in books and on the Internet. This article offers a number of activities that can easily be carried out in a science class. They make use of the phenomenon of "Persistence of Vision." The activities presented herein demonstrate the functionality of the phenakistoscope, the…

  6. Combined time-series resistivity and geochemical tracer techniques to examine submarine groundwater discharge at Dor Beach, Israel

    USGS Publications Warehouse

    Swarzenski, P.W.; Burnett, W.C.; Greenwood, W.J.; Herut, B.; Peterson, R.; Dimova, N.; Shalem, Y.; Yechieli, Y.; Weinstein, Y.

    2006-01-01

    A high-resolution, stationary geophysical and geochemical survey was conducted at Dor Beach, Israel, to examine the shallow coastal hydrogeology and its control on the exchange of submarine groundwater with the shallow Mediterranean Sea. Time-series resistivity profiles using a new 56 electrode (112-m long) marine cable produced detailed profiles of the fresh water/salt water interface and the subtle response of this interface to tidal excursions and other forcing factors. Such information, when ground-truthed with representative pore water salinities and formation resistivity values, can provide unique information of the extent and rates of submarine groundwater discharge (SGD). Time-series 222Rn measurements of the adjacent coastal water column complemented these geophysical techniques and were modeled to yield integrated advective flow rates across the sediment/water interface, which at Dor Beach ranged from about 0 to 30 cm day-1 (mean = 7.1 cm d-1), depending on the tidal range. Such results suggest that the underlying hydrogeologic framework at Dor is favorable for substantial SGD. Extrapolating these SGD estimates across a 100-m wide coastal zone implies that the Rn-derived SGD rate would equal ???7.1 m3 d-1 per m of shoreline, and that the source of this discharging groundwater is a complex mixture of fresh groundwater derived from the upland Kurkar deposits, as well as locally recycled seawater. Copyright 2006 by the American Geophysical Union.

  7. Combined ERT-TDEM measurements for studying submarine groundwater discharge (SGD) at Dor Beach, Israel

    NASA Astrophysics Data System (ADS)

    Levi, E.; Goldman, M.; Weinstein, Y.; Yechieli, Y.

    2008-12-01

    During last years, Dor Beach became a major test site for hydrogeological, geochemical and geophysical investigations of the SGD phenomenon in Israel. The high resolution time-series ERT measurements using 112-m long cable carried out at the site in 2006 have provided important information regarding shallow coastal hydrogeology up to the maximum exploration depth of approximately 20 m (Swarzenski et al, 2006). In a recent experiment (summer 2008), we focused on deeper parts of the site. This goal was achieved by using roughly two times longer shore diagonal and shore perpendicular ERT lines accompanied by onshore TDEM measurements. Such a combination allowed obtaining reliable information regarding the distribution of electrical resistivity up to a maximum depth of approximately 100 m. As a result, an additional high resistivity structure has been detected at a depth of approximately 63 m, which most likely represents the underlying Carmel Cretaceous aquifer saturated with water of lower than seawater salinity. Two saline/freshwater interfaces were detected at depths of approximately 17 m and 49 m. The upper interface between fresh and brackish water was detected by both ERT and TDEM, while the lower fresh/seawater interface was detected by TDEM alone.

  8. Detecting moving objects under a moving camera in complex environments

    NASA Astrophysics Data System (ADS)

    Zhang, Genyuan; Yu, Qin; Yang, Sisi; Zhou, Hong

    2015-03-01

    Robust detection of moving objects in image sequences is an essential part of many vision applications. However, it is not easily achievable with a moving camera since the camera and moving objects motions are mixed together. In this paper we propose a method to detect moving objects under a moving camera. The camera ego-motion is compensated by the corresponding feature sets. The difference image between two consecutive images that ego-motion is compensated is transformed into a binary image using k-means algorithm. According to the clustering results, the region of interest where moving objects are likely to exist is searched by the projection approach. Then local threshold and contour filling methods are applied to detect the accurate moving objects. Experimental results on real image sequences demonstrate that our method can get intact moving objects in the case of a moving camera efficiently.

  9. Electrostatics of moving plasma

    SciTech Connect

    Ignatov, A. M.

    2013-07-15

    The stability of charge distribution over the surface of a conducting body in moving plasma is analyzed. Using a finite-width plate streamlined by a cold neutralized electron flow as an example, it is shown that an electrically neutral body can be unstable against the development of spontaneous polarization. The plasma parameters at which such instability takes place, as well as the frequency and growth rate of the fundamental mode of instability, are determined.

  10. Moving with the sun.

    PubMed

    Hjelm, N M; Hazlett, C; Hsieh, R; Lee, J C

    2001-05-01

    A global 24-hour telemedicine conference entitled, "Moving with the Sun" was successfully completed on June 30 and July 1 1997 between participants from Hong Kong and China, as well as with sixteen major international medical centres around the globe. In addition to celebrating the return of Hong Kong to the People's Republic of China, the conference also signified the establishment of the Chinese University of Hong Kong, and Hong Kong as a bridge between Western countries and the PRC. PMID:11311663

  11. AB 1725: A Comprehensive Analysis.

    ERIC Educational Resources Information Center

    California Community Colleges, Sacramento. Board of Governors.

    A summary and analysis is provided of California Assembly Bill (AB) 1725, a reform bill that provides new direction and support for the state's community colleges. The analysis addresses each of the eight sections of the bill: (1) mission, highlighting reforms related to mission statements, transfer core curriculum, remedial limits, articulation…

  12. The VLT-FLAMES Tarantula Survey: Multiplicity and Dynamics of the Massive Stars in 30 Dor

    NASA Astrophysics Data System (ADS)

    Sana, H.; Dunstall, P. R.; Hénault-Brunet, V.; Walborn, N. R.; de Koter, A.; de Mink, S. E.; Dufton, P. L.; Evans, C. J.; Maíz Apellániz, J.; Taylor, W. D.; Vink, J. S.

    2012-12-01

    We present the first results on the multiplicity and dynamics of the OB star population in 30 Dor obtained in the framework of the VLT-FLAMES Tarantula Survey. Based on their radial velocity (RV) variations, we have identified over 100 O-type and about 160 B-type spectroscopic binaries. The observed spectroscopic binary fraction for the O and B stars in our sample is of the order 30-35%. Preliminary considerations on the binary detection rate suggest a true spectroscopic binary fraction of the order of 50%. The overall RV dispersion (σRV) of the O stars in the complete sample is about 10 km s-1 but we note that the NGC 2060 and NGC 2070 regions show slightly different dynamical properties. We identified 17 O-type runaway candidates that show deviating RVs. One third of these candidates are On/nn/nnn stars, indicating a large rotational velocity. We show that the fast rotators have different RV properties than the average of the sample and are distributed throughout the field. This suggests a link between large rotation rate and peculiar RVs and, ultimately, the runaway phenomenon. Using the O stars observed within 25″(˜ 6 pc) from the core of R136, we obtain a preliminary upper limit of 7.5 km s-1 to σdyn. Given that this value has yet to be corrected down for contributions of non-detected long period binaries, this indicates that R136 is possibly a dynamically stable cluster.

  13. Determination of the bond-angle distribution in vitreous B{sub 2}O{sub 3} by {sup 11}B double rotation (DOR) NMR spectroscopy

    SciTech Connect

    Hung, I.; Howes, A.P.; Parkinson, B.G.; Anupold, T.; Samoson, A.; Brown, S.P.; Harrison, P.F.; Holland, D.; Dupree, R.

    2009-09-15

    The B-O-B bond angle distributions for both ring and non-ring boron sites in vitreous B{sub 2}O{sub 3} have been determined by {sup 11}B double rotation (DOR) NMR and multiple-quantum (MQ) DOR NMR. The [B{sub 3}O{sub 6}] boroxol rings are observed to have a mean internal B-O-B angle of 120.0+-0.7 deg. with a small standard deviation, sigma{sub R}=3.2+-0.4 deg., indicating that the rings are near-perfect planar, hexagonal structures. The rings are linked predominantly by non-ring [BO{sub 3}] units, which share oxygens with the boroxol ring, with a mean B{sub ring}-O-B{sub non-ring} angle of 135.1+-0.6 deg. and sigma{sub NR}=6.7+-0.4 deg. In addition, the fraction of boron atoms, f, which reside in the boroxol rings has been measured for this sample as f=0.73+-0.01. - Graphical abstract: Connectivities and B-O-B bond angle distributions of ring and non-ring boron atoms in v-B{sub 2}O{sub 3} have been determined by {sup 11}B double rotation (DOR) NMR, multiple-quantum (MQ) DOR NMR and spin-diffusion DOR. Near-perfect planar, hexagonal [B{sub 3}O{sub 6}] boroxol rings are shown to be present. Display Omitted

  14. GPS Moving Vehicle Experiment

    NASA Technical Reports Server (NTRS)

    Oaks, O. J.; Reid, Wilson; Wright, James; Duffey, Christopher; Williams, Charles; Warren, Hugh; Zeh, Tom; Buisson, James

    1996-01-01

    The Naval Research Laboratory (NRL) in the development of timing systems for remote locations, had a technical requirement for a Y code (SA/AS) Global Positioning System (GPS) precise time transfer receiver (TTR) which could be used both in a stationary mode or mobile mode. A contract was awarded to the Stanford Telecommunication Corporation (STEL) to build such a device. The Eastern Range (ER) als had a requirement for such a receiver and entered into the contract with NRL for the procurement of additional receivers. The Moving Vehicle Experiment (MVE) described in this paper is the first in situ test of the STEL Model 5401C Time Transfer System in both stationary and mobile operations. The primary objective of the MVE was to test the timing accuracy of the newly developed GPS TTR aboard a moving vessel. To accomplish this objective, a joint experiment was performed with personnel from NRL and the er at the Atlantic Undersea Test and Evaluation Center (AUTEC) test range at Andros Island. Results and discussion of the test are presented in this paper.

  15. MOVES2014: Evaporative Emissions Report

    EPA Science Inventory

    Vehicle evaporative emissions are now modeled in EPA’s MOVES according to physical processes, permeation, tank vapor venting, liquid leaks, and refueling emissions. With this update, the following improvements are being incorporated into MOVES evaporative emissions methodology, a...

  16. The Secret Lives of Cepheids: Discovery of Strong FUV Emissions in the Classical Cepheids Polaris and beta Dor

    NASA Astrophysics Data System (ADS)

    Engle, Scott G.; Guinan, E. F.; Evans, N. R.

    2006-12-01

    We report on the surprising recent discovery of strong FUV emissions in two bright, nearby Classical Cepheids from analyses of FUSE archival observations. Polaris (V = +1.98, F7 Ib-II, P = 3.97-d; d 132-pc) and beta Dor (V = +3.77, F6 Ia; P = 9.84-d; d 350-pc) are currently the only two Cepheids to have been observed with FUSE, and beta Dor is the only one to have multiple spectra. The FUSE wavelength region is ideal for such a study since it is uncontaminated by the continua of these F supergiants. Both Cepheids show strong C III (977, 1176) and O VI (1032, 1038) emissions, indicative of 50,000 500,000 K plasma, well above the photospheric temperatures. Also, more remarkably, beta Dor displays variability in the FUV emission strengths which appears to be correlated to its 9.84-d pulsation period. This phenomenon has never before been observed in Cepheids. The FUV studies are presented along with our recent Chandra X-ray observation of Polaris, in which an X-ray detection (log Lx = 28.8 ergs/sec) was found. Further FUV/X-ray observations have been proposed with FUSE/XMM to unambiguously determine the origin and nature of the observed high energy emissions from the targets, possibly arising from warm winds, shocks, or pulsationally induced magnetic activity. The initial results of this study will be discussed, along with their impact on understanding the structure, heating, dynamics and possible magnetic activity of Cepheid (and related Hybrid Star) atmosphere. We gratefully acknowledge support for this project from NASA grant Chandra-GO6-7011A and NSF grant AST05-07542.

  17. Chondrocyte Moves: clever strategies?

    PubMed Central

    Morales, Teresa I.

    2007-01-01

    Goals To review the literature on chondrocyte movements and to develop plausible hypothesis for further work. Design Chondrocyte movements are herein defined as translocations of the cell body. To set the stage for a discussion of chondrocyte moves, a brief overview of cell migration in other cell types is presented, including a discussion of the challenges that cells find when moving within tissues. Reports of isolated chondrocyte migration in vitro (isolated cell systems) and ex vivo (cartilage organ cultures) are then summarized, followed by a discussion of recent studies that infer chondrocyte movements in vivo. Results Investigators from different laboratories have observed chondrocyte motility in vitro. I became interested in the question of whether articular chondrocytes retained their phenotype during their migratory excursions. We devised a simple method to separate migratory and stationary chondrocytes and then showed that migratory chondrocytes synthesized collagen II but not I—consistent with a differentiated phenotype. Our time-lapse video microscopy studies showed that the cells displayed appropriate movement kinetics, albeit with low speed and directionality. Similarly, others have presented data consistent with slow movement of chondrocytes out of cartilage explants. It is important to decipher whether these in vitro movements reflect physiological states and if so, which events are simulated. Examples of in vivo studies that have inferred chondrocyte movements include those describing rotational or gliding movements of chondrocytes in the proliferative zone of the growth plate and its importance in the growth process; and the notion that chondrocytes move from the cartilage endplates to the nucleus pulposus in the spine of rabbits and rats during development. Such studies are consistent with the hypothesis that chondrocytes exhibit highly controlled and specialized movements during tissue growth and remodeling in vivo. On the other hand, the

  18. Moving particle composition analyzer

    NASA Technical Reports Server (NTRS)

    Auer, S. O. (Inventor)

    1976-01-01

    A mass spectrometry apparatus for analyzing the composition of moving microscopic particles is introduced. The apparatus includes a capacitor with a front electrode upon which the particles impinge, a back electrode, and a solid dielectric sandwiched between the front and back electrodes. In one embodiment, the electrodes and dielectric are arcuately shaped as concentric peripheral segments of different spheres having a common center and different radii. The front electrode and dielectric together have a thickness such that an impinging particle can penetrate them. In a second embodiment, the capacitor has planar, parallel electrodes, in which case the ejected positive ions are deflected downstream of a planar grid by a pair of spaced, arcuate capacitor plates having a region between them through which the ejected ions travel.

  19. Moving Single Atoms

    NASA Astrophysics Data System (ADS)

    Stuart, Dustin

    2016-05-01

    Single neutral atoms are promising candidates for qubits, the fundamental unit of quantum information. We have built a set of optical tweezers for trapping and moving single Rubidium atoms. The tweezers are based on a far off-resonant dipole trapping laser focussed to a 1 μm spot with a single aspheric lens. We use a digital micromirror device (DMD) to generate dynamic holograms of the desired arrangement of traps. The DMD has a frame rate of 20 kHz which, when combined with fast algorithms, allows for rapid reconfiguration of the traps. We demonstrate trapping of up to 20 atoms in arbitrary arrangements, and the transport of a single-atom over a distance of 14 μm with continuous laser cooling, and 5 μm without. In the meantime, we are developing high-finesse fibre-tip cavities, which we plan to use to couple pairs of single atoms to form a quantum network.

  20. Hanford plots reactor move

    SciTech Connect

    King, H.

    1993-10-04

    Anxious to show skeptics some bang for the mounting cleanup bucks, the US Dept. of Energy has taken steps to get a large and visible project under way at its Hanford weapon plant-moving eight old nuclear reactors to permanent burial at an inland dump site. The effort, conservatively budgeted at $235 million, will be the eastern Washington site's largest [open quotes]D D[close quotes]-decontamination and decommissioning-project yet. Last month, DOE unveiled its final record of decision for the plants that spells out D D options-from doing nothing to immediate removal of entire reactor blocks. At issue are reactors built from 1943 to 1963 along the Columbia River. Defunct since 1971, they once produced plutonium.

  1. Moving belt metal detector

    NASA Astrophysics Data System (ADS)

    Nelson, Carl V.; Mendat, Deborah P.; Huynh, Toan B.

    2006-05-01

    The Johns Hopkins University Applied Physics Laboratory (APL) has developed a prototype metal detection survey system that will increase the search speed of conventional technology while maintaining high sensitivity. Higher search speeds will reduce the time to clear roads of landmines and improvised explosive devices (IED) and to locate unexploded ordnance (UXO) at Base Realignment and Closure (BRAC) sites, thus reducing remediation costs. The new survey sensor system is called the moving belt metal detector (MBMD) and operates by both increasing sensor speed over the ground while maintaining adequate sensor dwell time over the target for good signal-to-noise ratio (SNR) and reducing motion-induced sensor noise. The MBMD uses an array of metal detection sensors mounted on a flexible belt similar to a tank track. The belt motion is synchronized with the forward survey speed so individual sensor elements remain stationary relative to the ground. A single pulsed transmitter coil is configured to provide a uniform magnetic field along the length of the receivers in ground contact. Individual time-domain electromagnetic induction (EMI) receivers are designed to sense a single time-gate measurement of the total metal content. Each sensor module consists of a receiver coil, amplifier, digitizing electronics and a low power UHF wireless transmitter. This paper presents the survey system design concepts and metal detection data from various targets at several survey speeds. Although the laboratory prototype is designed to demonstrate metal detection survey speeds up to 10 m/s, higher speeds are achievable with a larger sensor array. In addition, the concept can be adapted to work with other sensor technologies not previously considered for moving platforms.

  2. Pressure tracking control of vehicle ABS using piezo valve modulator

    NASA Astrophysics Data System (ADS)

    Jeon, Juncheol; Choi, Seung-Bok

    2011-03-01

    This paper presents a wheel slip control for the ABS(anti-lock brake system) of a passenger vehicle using a controllable piezo valve modulator. The ABS is designed to optimize for braking effectiveness and good steerability. As a first step, the principal design parameters of the piezo valve and pressure modulator are appropriately determined by considering the braking pressure variation during the ABS operation. The proposed piezo valve consists of a flapper, pneumatic circuit and a piezostack actuator. In order to get wide control range of the pressure, the pressure modulator is desired. The modulator consists of a dual-type cylinder filled with different substances (fluid and gas) and a piston rod moving vertical axis to transmit the force. Subsequently, a quarter car wheel slip model is formulated and integrated with the governing equation of the piezo valve modulator. A sliding mode controller to achieve the desired slip rate is then designed and implemented. Braking control performances such as brake pressure and slip rate are evaluated via computer simulations.

  3. Dust on the Move

    NASA Technical Reports Server (NTRS)

    2006-01-01

    [figure removed for brevity, see original site] Context image for PIA06763 Dust on the Move

    This dust avalanche is located on the rim material of an unnamed crater to the east of Tikhonravov Crater.

    Image information: VIS instrument. Latitude 15.0N, Longitude 43.1E. 18 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  4. ALS renewal moves forward

    NASA Astrophysics Data System (ADS)

    Falcone, R. W.; Feinberg, B.; Hussain, Z.; Kirz, J.; Krebs, G. F.; Padmore, H. A.; Robin, D. S.; Robinson, A. L.

    2007-11-01

    As the result of an extensive long-term planning process involving all its stakeholders—management, staff, and users—the ALS has seen its future and is aggressively moving ahead to implement its vision for keeping the facility at the cutting edge for the next 2-3 decades. The evolving strategic plan now in place aims to renew the ALS so it can address a new generation of fundamental questions about size dependent and dimensional-confinement phenomena at the nanoscale; correlation and complexity in physical, biological, and environmental systems; and temporal evolution, assembly, dynamics and ultrafast phenomena. The renewal spans three areas: (1) increased staffing at beamlines to support the growing user community and safety professionals to keep an increasingly complex facility hazard free; (2) implementing advances in accelerator, insertion device, beamline, and detector technology that will make it possible for ALS users to address emerging grand scientific and technological challenges with incisive world-class tools; and (3) construction of a user support building and guest housing that will increase the safety and user friendliness of the ALS by providing users office, meeting, experiment staging, and laboratory space for their work and on-site accommodations at reasonable rates.

  5. Efficient data association for move-stop-move target tracking

    NASA Astrophysics Data System (ADS)

    Sathyan, T.; McDonald, Mike; Kirubarajan, T.

    2008-04-01

    In this paper, we present an efficient data association algorithm for tracking ground targets that perform move-stop-move maneuvers using ground moving target indicator (GMTI) radar. A GMTI radar does not detect the targets whose radial velocity falls below a certain minimum detectable velocity. Hence, to avoid detection enemy targets deliberately stop for some time before moving again. When targets perform move-stop-move maneuvers, a missed detection of a target by the radar leads to an ambiguity as to whether it is because the target has stopped or due to the probability of detection being less than one. A solution to track move-stop-move target tracking is based on the variable structure interacting multiple model (VS-IMM) estimator in an ideal scenario (single target tracking with no false measurements) has been proposed. This solution did not consider the data association problem. Another solution, called two-dummy solution, considered the data association explicitly and proposed a solution based on the multiframe assignment algorithm. This solution is computationally expensive, especially when the scenario is complex (e.g., high target density) or when one wants to perform high dimensional assignment. In this paper, we propose an efficient multiframe assignment-based solution that considers the second dummy measurement as a real measurement than a dummy. The proposed algorithm builds a less complex assignment hypothesis tree, and, as a result, is more efficient in terms of computational resource requirement.

  6. Do Individuals with Fragile X Syndrome Show Developmental Stuttering or Not? Comment on "Speech Fluency in Fragile X Syndrome" by Van Borsel, Dor and Rondal

    ERIC Educational Resources Information Center

    Howell, Peter

    2008-01-01

    Van Borsel, Dor, and Rondal (2007) examined the speech of seven boys and two young male adults with fragile X syndrome and considered whether their speech was comparable to that reported in the developmental stuttering literature. They listed five criteria which led them to conclude that the speech patterns of speakers with fragile X syndrome…

  7. A Spatial Study of X-ray Properties in Superbubble 30 Dor C with XMM-Newton

    NASA Astrophysics Data System (ADS)

    Babazaki, Yasunori; Mitsuishi, Ikuyuki; SANO, Hidetoshi; Yoshiike, Satoshi; Fukuda, Tatsuya; Maruyama, Shohei; Fujii, Kosuke; Fukui, Yasuo; Tawara, Yuzuru; Matsumoto, Hironori

    2015-08-01

    Supernova remnants (SNRs) in the Galaxy are believed to be most likely accelerators of cosmic-rays (CRs) in an energy range less than 3×10^15 eV. Thus SNRs emit synchrotron X-rays by high-energy electrons. Sano et al. (2014) investigated spatially-resolved X-ray spectral properties of a shell-type SNR RX1713.77-3946 which shows strong non-thermal X-ray emissions. A large variation in the photon index is found and the photon index tends to be hard with increasing an interstellar gas density, suggesting that CR electrons are efficiently accelerated in denser interstellar gas environments. Few studies have focused on a photon index variation in superbubbles which possess 100-1000 pc diameter shells of swept-up interstellar materials containing hot (~10^6 K) shock-heated gas. The superbubble 30 Dor C in the Large Magellanic Cloud is one of the best targets for examining the photon index variation, because 30 Dor C is by far strong non-thermal X-ray emissions, and thus provides an ideal laboratory for probing non-thermal emission mechanisms in the supperbubble. We investigated X-ray spectral properties of the superbubble with a high spatial resolution of on the order of 10 pc. Consequently, the spectra in the west region of 30 Dor C can be described with a combination of absorbed thermal and non-thermal models while the spectra in the east region can be fitted with an absorbed non-thermal model. The photon index and intensity in 2-10 keV show variations of 2.0-3.5 and (0.6-8.0) × 10^-7 erg/s/cm^2, respectively. The temperature of the thermal component ranges from ~0.1 to ~0.3 keV. We will discuss an interaction between the hot gas and an interstellar gas using mutiwavelength data.

  8. AB INITIO AND CALPHAD THERMODYNAMICS OF MATERIALS

    SciTech Connect

    Turchi, P A

    2004-04-14

    Ab initio electronic structure methods can supplement CALPHAD in two major ways for subsequent applications to stability in complex alloys. The first one is rather immediate and concerns the direct input of ab initio energetics in CALPHAD databases. The other way, more involved, is the assessment of ab initio thermodynamics {acute a} la CALPHAD. It will be shown how these results can be used within CALPHAD to predict the equilibrium properties of multi-component alloys.

  9. Amplitude Spectrum Variability in gamma Dor and delta Sct Pulsating Variable Stars Observed by the NASA Kepler Spacecraft

    NASA Astrophysics Data System (ADS)

    Guzik, Joyce Ann; Kosak, Katie; Bradley, Paul A.; Jackiewicz, Jason

    2015-08-01

    The NASA Kepler spacecraft data has revealed a large number of new multimode nonradially pulsating gamma Dor and delta Sct variable stars. The Kepler high precision long time-series photometry makes it possible to study amplitude variations of the frequencies. We summarize recent literature on amplitude and frequency variations in nonradially pulsating variables. We apply several methods, including those we have developed, and the wavelet technique of the VStar software (http://www.aavso.org/vstar-overview), to study amplitude variability in about a dozen gamma Doradus or delta Scuti candidate variable stars observed for several quarters as part of the Kepler Guest Observer program. We discuss the magnitude and timescale of the amplitude variations, and the presence or absence of correlations between amplitude variations for different frequencies of a given star. We discuss proposed causes of amplitude spectrum variability that will require further investigation.

  10. V2653 Ophiuchii with a pulsating component and Ppuls - Porb, Ppuls - g correlations for γ Dor type pulsators

    NASA Astrophysics Data System (ADS)

    Çakırlı, Ö.; Ibanoglu, C.

    2016-05-01

    We present new spectroscopic observations of the double-lined eclipsing binary V2653 Ophiuchii. The photometric observations obtained by ASAS were analyzed and combined with the analysis of radial velocities for deriving the absolute parameters of the components. Masses and radii were determined for the first time as Mp = 1.537 ± 0.021 M⊙ and Rp = 2.215 ± 0.055 R⊙, Ms = 1.273 ± 0.019 M⊙ and Rs = 2.000 ± 0.056 R⊙ for the components of V2653 Oph. We estimate an interstellar reddening of 0.15 ± 0.08 mag and a distance of 300 ± 50 pc for the system, both supporting the membership of the open cluster Collinder 359. Using the out-of-eclipse photometric data we have made frequency analysis and detected a periodic signal at 1.0029 ± 0.0019 c/d. This frequency and the location of the more massive star on the HR diagram lead to classification of a γ Dor type variable. Up to date only eleven γ Dor type pulsators in the eclipsing binaries have been discovered. For six out of 11 systems, the physical parameters were determined. Although a small sample, we find empirical relations that Ppuls ∝ Porb0.43 and Ppuls ∝ g-0.83. While the pulsation periods increase with longer orbital periods, they decrease with increasing surface gravities of pulsating components and gravitational pull exerted by the companions. We present, briefly, the underlying physics behind the correlations we derived.

  11. Track segment association for ground moving targets with evasive move-stop-move maneuvers

    NASA Astrophysics Data System (ADS)

    Zhang, Shuo; Bar-Shalom, Yaakov

    2010-04-01

    In a real tracking system, track breakages can occur due to highly maneuvering targets, low detection probability, or clutter. Previously, a track segment association approach (TSA) was developed for an airborne early warning (AEW) system to improve track continuity by"stitching" broken track segments pertaining to the same target. However, this technique cannot provide satisfactory association performance in tracking with a GMTI radar ground moving targets employing evasive move-stop-move maneuvers. To avoid detection by a GMTI radar, targets can deliberately stop for some time before moving again. Since a GMTI radar does not detect a target when the radial velocity (along the line-of-sight from the sensor) falls below a certain minimum detectable velocity (MDV), the move-stop-move maneuvers of the targets usually lead to broken tracks as a result. We present a new TSA technique which employs a dummy track to formulate a complete association. By using an IMM estimator with state-dependent mode transition probabilities (IMM-SDP) for track segment prediction (forward and backward), the proposed algorithm can effectively stitch both "regular" broken tracks and broken tracks due to targets' move-stop-move maneuvers. Comparisons are given to show the advantages of the proposed algorithm in broken tracks reduction and track continuity improvement.

  12. Ultrasound Biomicroscopy Comparison of Ab Interno and Ab Externo Intraocular Lens Scleral Fixation.

    PubMed

    Horiguchi, Lie; Garcia, Patricia Novita; Malavazzi, Gustavo Ricci; Allemann, Norma; Gomes, Rachel L R

    2016-01-01

    Purpose. To compare ab interno and ab externo scleral fixation of posterior chamber intraocular lenses (PCIOL) using ultrasound biomicroscopy (UBM). Methods. Randomized patients underwent ab externo or ab interno scleral fixation of a PCIOL. Ultrasound biomicroscopy was performed 3 to 6 months postoperatively, to determine PCIOL centration, IOL distance to the iris at 12, 3, 6, and 9 hours, and haptics placement in relation to the ciliary sulcus. Results. Fifteen patients were enrolled in the study. The ab externo technique was used in 7 eyes (46.6%) and the ab interno in 8 eyes (53.3%). In the ab externo technique, 14 haptics were located: 4 (28.57%) in the ciliary sulcus; 2 (14.28%) anterior to the sulcus; and 8 (57.14%) posterior to the sulcus, 6 in the ciliary body and 2 posterior to the ciliary body. In the ab interno group, 4 haptics (25.0%) were in the ciliary sulcus, 2 (12.50%) anterior to the sulcus, and 10 (75.0%) posterior to the sulcus, 4 in the ciliary body and 6 posterior to the ciliary body. Conclusions. Ab externo and ab interno scleral fixation techniques presented similar results in haptic placement. Ab externo technique presented higher vertical tilt when compared to the ab interno. PMID:27293878

  13. Ultrasound Biomicroscopy Comparison of Ab Interno and Ab Externo Intraocular Lens Scleral Fixation

    PubMed Central

    Horiguchi, Lie; Garcia, Patricia Novita; Malavazzi, Gustavo Ricci; Allemann, Norma

    2016-01-01

    Purpose. To compare ab interno and ab externo scleral fixation of posterior chamber intraocular lenses (PCIOL) using ultrasound biomicroscopy (UBM). Methods. Randomized patients underwent ab externo or ab interno scleral fixation of a PCIOL. Ultrasound biomicroscopy was performed 3 to 6 months postoperatively, to determine PCIOL centration, IOL distance to the iris at 12, 3, 6, and 9 hours, and haptics placement in relation to the ciliary sulcus. Results. Fifteen patients were enrolled in the study. The ab externo technique was used in 7 eyes (46.6%) and the ab interno in 8 eyes (53.3%). In the ab externo technique, 14 haptics were located: 4 (28.57%) in the ciliary sulcus; 2 (14.28%) anterior to the sulcus; and 8 (57.14%) posterior to the sulcus, 6 in the ciliary body and 2 posterior to the ciliary body. In the ab interno group, 4 haptics (25.0%) were in the ciliary sulcus, 2 (12.50%) anterior to the sulcus, and 10 (75.0%) posterior to the sulcus, 4 in the ciliary body and 6 posterior to the ciliary body. Conclusions. Ab externo and ab interno scleral fixation techniques presented similar results in haptic placement. Ab externo technique presented higher vertical tilt when compared to the ab interno. PMID:27293878

  14. Comments on Racetrack playa: Rocks moved by wind alone

    NASA Astrophysics Data System (ADS)

    Sanz-Montero, M. E.; Cabestrero, Ó.; Rodríguez-Aranda, J. P.

    2016-03-01

    The mechanisms by which rocks move across the beds of playa lakes leaving tracks continue to be debated (Sanz-Montero and Rodríguez-Aranda, 2013; Norris et al., 2014; Sanz-Montero et al., 2015a,b; Baumgardner and Shaffer, 2015; Jones and Hooke, 2015). In this regard, the article by Jones and Hooke (Aeolian Research 19, 2015) is particularly interesting since it provides a description of these mechanisms by R. Jones who, during a storm event in 1972, was probably the first person to witness movement of rocks. The dominant meteorological conditions described by Jones during the period when the tracks were formed are, significantly, rather similar to those previously described by Clements (1952) at Little Bonnie Claire Playa (Nevada, USA). The storm conditions referred to in the article also coincide with the observations, measurements and deductions made by Sanz-Montero and Rodríguez-Aranda (2013) and Sanz-Montero et al. (2015a,b) at Altillo Chica playa lake, Central Spain. Furthermore, we were able to carry out an on-site analysis of the sedimentary structures at Racetrack playa in June 2015, allowing us to verify the similarity of the features present at both sites. Together with the important role played by gusty winds in the formation of the tracks, all the above mentioned studies point to the presence of a thin veneer of water, just a few millimeters deep, in the area of the playa lake where the rock movements occur. However, Jones and Hooke (2015) disregard the force exerted by moving water and analyze the coefficient of friction assuming that the rocks are moved by wind alone. We offer an alternative explanation for the movement of rocks both at Racetrack and Altillo Chica playa lake which considers not only the wind but also the role played by moving water in conjunction with other parameters which modify the erosion thresholds (rocks acting as obstacles) and reduce friction (benthic microorganisms).

  15. Possible Functional Moving Toes Syndrome

    PubMed Central

    Vanegas-Arroyave, Nora; Panyakaew, Pattamon; Lamichhane, Dronacharya; Shulman, Lisa; Hallett, Mark

    2016-01-01

    Background Moving toes syndrome has been classically described as an organic movement disorder, on occasion related to peripheral nerve injuries. The association between nerve trauma and movement disorders has become a controversial topic, and the functional etiology of moving toes syndrome has recently been proposed. Case Report We describe two cases of moving toes syndrome with clinical features typically suggestive of a functional movement disorder. Discussion The presence of entrainability and distractibility in the described patients is an indication of attentional influences on their involuntary movements. However, it is possible that if there is a subcortical origin, the toe movements could be influenced by voluntary commands. PMID:27144090

  16. Quantization of systems with temporally varying discretization. II. Local evolution moves

    SciTech Connect

    Höhn, Philipp A.

    2014-10-15

    Several quantum gravity approaches and field theory on an evolving lattice involve a discretization changing dynamics generated by evolution moves. Local evolution moves in variational discrete systems (1) are a generalization of the Pachner evolution moves of simplicial gravity models, (2) update only a small subset of the dynamical data, (3) change the number of kinematical and physical degrees of freedom, and (4) generate a dynamical (or canonical) coarse graining or refining of the underlying discretization. To systematically explore such local moves and their implications in the quantum theory, this article suitably expands the quantum formalism for global evolution moves, constructed in Paper I [P. A. Höhn, “Quantization of systems with temporally varying discretization. I. Evolving Hilbert spaces,” J. Math. Phys. 55, 083508 (2014); e-print http://arxiv.org/abs/arXiv:1401.6062 [gr-qc

  17. Mobile Launcher Moves for Testing

    NASA Video Gallery

    In anticipation of launching NASA’s Space Launch System heavy-lift rocket later in this decade, engineers wanted to check the mobile launcher, or ML, to see how it would behave moving atop a craw...

  18. Rehabilitation Counselor Certification: Moving Forward

    ERIC Educational Resources Information Center

    Saunders, Jodi L.; Barros-Bailey, Mary; Chapman, Cindy; Nunez, Patricia

    2009-01-01

    This article provides a brief history of the Commission on Rehabilitation Counselor Certification and presents recent changes and strategic goals for moving forward. Challenges and opportunities for the profession in relation to certification are also discussed. (Contains 3 tables.)

  19. Ab initio nuclear structure theory

    NASA Astrophysics Data System (ADS)

    Negoita, Gianina Alina

    Ab initio no core methods have become major tools for understanding the properties of light nuclei based on realistic nucleon-nucleon (NN) and three-nucleon (NNN) interactions. A brief description is provided for the inter-nucleon interactions that fit two-body scattering and bound state data, as well as NNN interactions. Major new progress, including the goal of applying these interactions to solve for properties of nuclei, is limited by convergence issues. That is, with the goal of obtaining high precision solutions of the nuclear many-body Hamiltonian with no core methods (all nucleons treated on the same footing), one needs to proceed to very large basis spaces to achieve a convergence pattern suitable for extrapolation to the exact result. This thesis investigates (1) the similarity renormalization group (SRG) approach to soften the interaction, while preserving its phase shift properties, and (2) adoption of a realistic basis space using Woods-Saxon (WS) single-particle wavefunctions. Both have their advantages and limitations, discussed here. For (1), SRG was demonstrated by applying it to a realistic NN interaction, JISP16, in a harmonic oscillator (HO) representation. The degree of interaction softening achieved through a regulator parameter is examined. For (2), new results are obtained with the realistic JISP16 NN interaction in ab initio calculations of light nuclei 4He, 6He and 12C, using a WS basis optimized to minimize the ground-state energy within the truncated no core shell model. These are numerically-intensive many-body calculations. Finally, to gain insight into the potential for no core investigations of heavier nuclei, an initial investigation was obtained for the odd mass A = 47 - 49 region nuclei straddling 48Ca. The motivation for selecting these nuclei stems from the aim of preparing for nuclear double beta-decay studies of 48Ca. In these heavier systems, phenomenological additions to the realistic NN interaction determined by previous

  20. Postural Change Effects on Infants' AB Task Performance: Visual, Postural, or Spatial?

    ERIC Educational Resources Information Center

    Lew, Adina R.; Hopkins, Brian; Owen, Laura H.; Green, Michael

    2007-01-01

    Smith and colleagues (Smith, L. B., Thelen, E., Titzer, R., & McLin, D. (1999). Knowing in the context of acting: The task dynamics of the A-not-B error. "Psychological Review, 106," 235-260) demonstrated that 10-month-olds succeed on a Piagetian AB search task if they are moved from a sitting position to a standing position between A and B…

  1. Ab initio phonon limited transport

    NASA Astrophysics Data System (ADS)

    Verstraete, Matthieu

    We revisit the thermoelectric (TE) transport properties of two champion materials, PbTe and SnSe, using fully first principles methods. In both cases the performance of the material is due to subtle combinations of structural effects, scattering, and phase space reduction. In PbTe anharmonic effects are completely opposite to the predicted quasiharmonic evolution of phonon frequencies and to frequently (and incorrectly) cited extrapolations of experiments. This stabilizes the material at high T, but also tends to enhance its thermal conductivity, in a non linear manner, above 600 Kelvin. This explains why PbTe is in practice limited to room temperature applications. SnSe has recently been shown to be the most efficient TE material in bulk form. This is mainly due to a strongly enhanced carrier concentration and electrical conductivity, after going through a phase transition from 600 to 800 K. We calculate the transport coefficients as well as the defect concentrations ab initio, showing excellent agreement with experiment, and elucidating the origin of the double phase transition as well as the new charge carriers. AH Romero, EKU Gross, MJ Verstraete, and O Hellman PRB 91, 214310 (2015) O. Hellman, IA Abrikosov, and SI Simak, PRB 84 180301 (2011)

  2. A spinor boson AB chain

    NASA Astrophysics Data System (ADS)

    Cruz Reyes, Greis Julieth; Franco, Roberto; Silva Valencia, Jereson; Universidad Santo Tomas Collaboration; Universidad Nacional de Colombia Collaboration

    Recent research is focused on superlattices arising from optical lattices, which allow a tunable environment. Experimentally bosons present transitions from superfluid to Mott insulator by changing the energy offset in the unit cell [Nat. Commun. 5:5735 (2014)]. Many studies displayed that ground state of spinless boson systems on superlattices present superfluid, Mott insulator and an additional CDW phase created by the energy shift between the sites into the unit cell [Phys. Rev. A 83, 053621 (2011)]. The first confinement methods were magnetic traps, which freezes the spin; with optical lattices the grade of freedom of spin plays an important role. We consider bosons with spin S =1 on a superlattice made by two sites with energy offset per unit cell (AB chain). The Hamiltonian that describes the system is the Bose-Hubbard model with the superlattice potential (W) and the exchange interaction (V) parameters. This model supports CDW, Mott insulator and superfluid phases. For W near to U, with V =0, Mott phase disappears, but for V increasing, a new CDW appears due to the spin interaction, while the half-integer CDW decrease. These results are widely different from spinless boson, where the CDW phases are stables.

  3. Ab inito investigation of hydrodesulferization

    SciTech Connect

    Tilson, J.L.; Marshall, C.L.; Brenner, J.R.

    1997-12-31

    We utilize MPP and vector computers to model the interaction of large sulfur-containing species bonded with hydrodesulfurization (HDS) catalysts. This work is made possible by the availability large aggregate memory, parallel computers. The ability of modern non-traditional computers to solve large-scale scientific problems has been demonstrated. This success is accomplished, in part, by access to portable low- and user-level software tools which exhibit good control over NUMA. ab initio SCF methods are used to characterize the energies of adsorption of poly-aromatic, sulfur-containing hydrocarbons onto a series of molecular-based models of MoS2. These hydrocarbon include thiophene (TP), benzothiophene (BT) and dibenzothiophene (DBT) which are representative of heavy crude feedstocks. Our work attempts to ascertain if a consistent model of adsorption onto a MoS2 surface exists and to determine how the electronic and steric configuration of each species affect their energies of interaction with the metal surface.

  4. GINGA Observations of AB Doradus

    NASA Astrophysics Data System (ADS)

    Vilhu, O.; Tsuru, T.; Collier Cameron, A.

    We report GINGA observations of the pre main sequence star AB Doradus (HD 36705), performed during 8 - 12 January, 1990. Some rotational modulation might be present. four X-ray flares were detected. Three of these events were similar to the EINSTEIN HRI-flare (Vilhu and Linsky, 1987), with decay times around 25 min. The last flare had long rise and decay times (100 min), resembling the EXOSAT flares observed by Collier Cameron et.al. (1988). The mean flare spectrum can be fitted by a thermal bremstrahlung with temperature 5.0 keV, or by a power-law model with photon index 2.2. The 3 upper limit of the Iron line equivalent width in the flare spectrum is 1 keV, weaker than predicted by thermal models. This Iron line anomaly was first discussed in the case of UX Ari by Tsuru et. al. (1989). However, normal equivalent widths can be derived from several EXOSAT spectra of active cool stars (Pallavicini and Tagliaferri, 1990). We discuss the possibility that the continuum from non-thermal electrons (producing also the microwave emission) could occasionally lower the apparent equivalent width. The mechanism works for reasonably low magnetic field strengths and electon power-law indexes. However, a large population of non-thermal electrons is needed (comparable to the thermal one). Stronger magnetic fields could explain the radio emission with less electrons, but then the non-thermal X-ray continuum remains small.

  5. The B AB AR detector

    NASA Astrophysics Data System (ADS)

    Aubert, B.; Bazan, A.; Boucham, A.; Boutigny, D.; De Bonis, I.; Favier, J.; Gaillard, J.-M.; Jeremie, A.; Karyotakis, Y.; Le Flour, T.; Lees, J. P.; Lieunard, S.; Petitpas, P.; Robbe, P.; Tisserand, V.; Zachariadou, K.; Palano, A.; Chen, G. P.; Chen, J. C.; Qi, N. D.; Rong, G.; Wang, P.; Zhu, Y. S.; Eigen, G.; Reinertsen, P. L.; Stugu, B.; Abbott, B.; Abrams, G. S.; Amerman, L.; Borgland, A. W.; Breon, A. B.; Brown, D. N.; Button-Shafer, J.; Clark, A. R.; Dardin, S.; Day, C.; Dow, S. F.; Fan, Q.; Gaponenko, I.; Gill, M. S.; Goozen, F. R.; Gowdy, S. J.; Gritsan, A.; Groysman, Y.; Hernikl, C.; Jacobsen, R. G.; Jared, R. C.; Kadel, R. W.; Kadyk, J.; Karcher, A.; Kerth, L. T.; Kipnis, I.; Kluth, S.; Kral, J. F.; Lafever, R.; LeClerc, C.; Levi, M. E.; Lewis, S. A.; Lionberger, C.; Liu, T.; Long, M.; Luo, L.; Lynch, G.; Luft, P.; Mandelli, E.; Marino, M.; Marks, K.; Matuk, C.; Meyer, A. B.; Minor, R.; Mokhtarani, A.; Momayezi, M.; Nyman, M.; Oddone, P. J.; Ohnemus, J.; Oshatz, D.; Patton, S.; Pedrali-Noy, M.; Perazzo, A.; Peters, C.; Pope, W.; Pripstein, M.; Quarrie, D. R.; Rasson, J. E.; Roe, N. A.; Romosan, A.; Ronan, M. T.; Shelkov, V. G.; Stone, R.; Strother, P. D.; Telnov, A. V.; von der Lippe, H.; Weber, T. F.; Wenzel, W. A.; Zizka, G.; Bright-Thomas, P. G.; Hawkes, C. M.; Kirk, A.; Knowles, D. J.; O'Neale, S. W.; Watson, A. T.; Watson, N. K.; Deppermann, T.; Koch, H.; Krug, J.; Kunze, M.; Lewandowski, B.; Peters, K.; Schmuecker, H.; Steinke, M.; Andress, J. C.; Barlow, N. R.; Bhimji, W.; Chevalier, N.; Clark, P. J.; Cottingham, W. N.; De Groot, N.; Dyce, N.; Foster, B.; Mass, A.; McFall, J. D.; Wallom, D.; Wilson, F. F.; Abe, K.; Hearty, C.; McKenna, J. A.; Thiessen, D.; Camanzi, B.; Harrison, T. J.; McKemey, A. K.; Tinslay, J.; Antohin, E. I.; Blinov, V. E.; Bukin, A. D.; Bukin, D. A.; Buzykaev, A. R.; Dubrovin, M. S.; Golubev, V. B.; Ivanchenko, V. N.; Kolachev, G. M.; Korol, A. A.; Kravchenko, E. A.; Mikhailov, S. F.; Onuchin, A. P.; Salnikov, A. A.; Serednyakov, S. I.; Skovpen, Yu. I.; Telnov, V. I.; Yushkov, A. N.; Booth, J.; Lankford, A. J.; Mandelkern, M.; Pier, S.; Stoker, D. P.; Zioulas, G.; Ahsan, A.; Arisaka, K.; Buchanan, C.; Chun, S.; Faccini, R.; MacFarlane, D. B.; Prell, S. A.; Rahatlou, Sh.; Raven, G.; Sharma, V.; Burke, S.; Callahan, D.; Campagnari, C.; Dahmes, B.; Hale, D.; Hart, P. A.; Kuznetsova, N.; Kyre, S.; Levy, S. L.; Long, O.; Lu, A.; May, J.; Richman, J. D.; Verkerke, W.; Witherell, M.; Yellin, S.; Beringer, J.; DeWitt, J.; Dorfan, D. E.; Eisner, A. M.; Frey, A.; Grillo, A. A.; Grothe, M.; Heusch, C. A.; Johnson, R. P.; Kroeger, W.; Lockman, W. S.; Pulliam, T.; Rowe, W.; Sadrozinski, H.; Schalk, T.; Schmitz, R. E.; Schumm, B. A.; Seiden, A.; Spencer, E. N.; Turri, M.; Walkowiak, W.; Wilder, M.; Williams, D. C.; Chen, E.; Dubois-Felsmann, G. P.; Dvoretskii, A.; Hanson, J. E.; Hitlin, D. G.; Kolomensky, Yu. G.; Metzler, S.; Oyang, J.; Porter, F. C.; Ryd, A.; Samuel, A.; Weaver, M.; Yang, S.; Zhu, R. Y.; Devmal, S.; Geld, T. L.; Jayatilleke, S.; Jayatilleke, S. M.; Mancinelli, G.; Meadows, B. T.; Sokoloff, M. D.; Bloom, P.; Broomer, B.; Erdos, E.; Fahey, S.; Ford, W. T.; Gaede, F.; van Hoek, W. C.; Johnson, D. R.; Michael, A. K.; Nauenberg, U.; Olivas, A.; Park, H.; Rankin, P.; Roy, J.; Sen, S.; Smith, J. G.; Wagner, D. L.; Blouw, J.; Harton, J. L.; Krishnamurthy, M.; Soffer, A.; Toki, W. H.; Warner, D. W.; Wilson, R. J.; Zhang, J.; Brandt, T.; Brose, J.; Dahlinger, G.; Dickopp, M.; Dubitzky, R. S.; Eckstein, P.; Futterschneider, H.; Kocian, M. L.; Krause, R.; Müller-Pfefferkorn, R.; Schubert, K. R.; Schwierz, R.; Spaan, B.; Wilden, L.; Behr, L.; Bernard, D.; Bonneaud, G. R.; Brochard, F.; Cohen-Tanugi, J.; Ferrag, S.; Fouque, G.; Gastaldi, F.; Matricon, P.; Mora de Freitas, P.; Renard, C.; Roussot, E.; T'Jampens, S.; Thiebaux, C.; Vasileiadis, G.; Verderi, M.; Anjomshoaa, A.; Bernet, R.; Di Lodovico, F.; Muheim, F.; Playfer, S.; Swain, J. E.; Falbo, M.; Bozzi, C.; Dittongo, S.; Folegani, M.; Piemontese, L.; Ramusino, A. C.; Treadwell, E.; Anulli, F.; Baldini-Ferroli, R.; Calcaterra, A.; de Sangro, R.; Falciai, D.; Finocchiaro, G.; Patteri, P.; Peruzzi, I. M.; Piccolo, M.; Xie, Y.; Zallo, A.; Bagnasco, S.; Buzzo, A.; Contri, R.; Crosetti, G.; Fabbricatore, P.; Farinon, S.; Lo Vetere, M.; Macri, M.; Minutoli, S.; Monge, M. R.; Musenich, R.; Pallavicini, M.; Parodi, R.; Passaggio, S.; Pastore, F. C.; Patrignani, C.; Pia, M. G.; Priano, C.; Robutti, E.; Santroni, A.; Bartoldus, R.; Dignan, T.; Hamilton, R.; Mallik, U.; Cochran, J.; Crawley, H. B.; Fischer, P. A.; Lamsa, J.; McKay, R.; Meyer, W. T.; Rosenberg, E. I.; Albert, J. N.; Beigbeder, C.; Benkebil, M.; Breton, D.; Cizeron, R.; Du, S.; Grosdidier, G.; Hast, C.; Höcker, A.; Lacker, H. M.; LePeltier, V.; Lutz, A. M.

    2002-02-01

    B AB AR, the detector for the SLAC PEP-II asymmetric e +e - B Factory operating at the ϒ(4 S) resonance, was designed to allow comprehensive studies of CP-violation in B-meson decays. Charged particle tracks are measured in a multi-layer silicon vertex tracker surrounded by a cylindrical wire drift chamber. Electromagnetic showers from electrons and photons are detected in an array of CsI crystals located just inside the solenoidal coil of a superconducting magnet. Muons and neutral hadrons are identified by arrays of resistive plate chambers inserted into gaps in the steel flux return of the magnet. Charged hadrons are identified by d E/d x measurements in the tracking detectors and by a ring-imaging Cherenkov detector surrounding the drift chamber. The trigger, data acquisition and data-monitoring systems, VME- and network-based, are controlled by custom-designed online software. Details of the layout and performance of the detector components and their associated electronics and software are presented.

  6. Moving Shadows, Moving Sun. Early Modem Sundials Restaging Miracles.

    PubMed

    Mersmann, Jasmin

    2015-01-01

    Irrespective of geo- or heliocentric presuppositions, the functioning of sundials is based on the observation of moving shadows or light spots. Even though the cast shadow was often simply used to indicate the time, it could also remind the users of the ephemerality of earthly things or function as an index of planetary movements. This article examines the various ways in which early modem sundials visually interpret the moving shadow or light spot. The instruments address the shadow in inscriptions, integrate it into their design (e.g., in cruciform dials) or even manipulate its course (as in the so-called Horologium Ahaz). Both the crucifix and the Ahaz dials not only refer to astronomical miracles but actually restage them. Even though by means of the horologium it was not possible to explain the Old Testament miracle of the shadow moving backward, adepts were able to recreate it on a terrestrial scale. PMID:26495586

  7. Collective rotation from ab initio theory

    NASA Astrophysics Data System (ADS)

    Caprio, M. A.; Maris, P.; Vary, J. P.; Smith, R.

    2015-08-01

    Through ab initio approaches in nuclear theory, we may now seek to quantitatively understand the wealth of nuclear collective phenomena starting from the underlying internucleon interactions. No-core configuration interaction (NCCI) calculations for p-shell nuclei give rise to rotational bands, as evidenced by rotational patterns for excitation energies, electromagnetic moments and electromagnetic transitions. In this review, NCCI calculations of 7-9Be are used to illustrate and explore ab initio rotational structure, and the resulting predictions for rotational band properties are compared with experiment. We highlight the robustness of ab initio rotational predictions across different choices for the internucleon interaction.

  8. Multifrequency observations of AB Doradus. X-ray flaring and rotational modulation of a young star

    NASA Astrophysics Data System (ADS)

    Vilhu, O.; Tsuru, T.; Collier Cameron, A.; Budding, E.; Banks, T.; Slee, B.; Ehrenfreund, P.; Foing, B. H.

    1993-11-01

    X-ray observations of AB Doradus, performed by the Large Area Counter (LAC) instrument of the GINGA satellite on January 1990, are reported. The observations covered 5 rotations of the star (2.6 days) during which 4 flares were detected. When added to the previously observed EINSTEIN and EXOSAT flares, a total of 7 X-ray flares in AB Dor have been observed so far. The flares seem to cluster around rotational phases 0.1-0.25 and 0.6-0.75 although the statistics are poor. The mean flare energies were around (1-3) x 1034 erg with peak luminosities (4-6) x 1030 ergs/s. The flaring loops were compact (ne = 1012/cu cm) and extended (1-2) x 1010 cm above the surface. Flare masses (1018 g) and frequencies (two per day) are similar to prominence-like cloud formations discovered previously in the star. The flare spectra can be best-fitted either by thermal Bremstrahlung with kT = 3-6 keV or with a power-law, with photon index gamma = 2.2-2.6. During the strongest flare peaks AB Dor is a 10 mCrab source with a Crab-like spectrum. The 3 sigma upper limit for the 6.7 keV iron line during the flares is somewhat smaller than predicted by thin plasma models. We discuss the possibility of lowering the equivalent width by an extra non-thermal continuum due to mildly relativistic electrons. Simultaneous 8.4 GHz observations during flare No. 1 gave only a marginal detection, constraining the magnetic field strength to less than 50 Gauss if the total X-ray continuum is non-thermal in origin. The sensitivity was not good enough to detect any clear modulation in the X-ray light curve, folded over the 0.514 d rotation period. Simultaneous 8.4 GHz observations were performed with the 64 m antenna of the Australia Telescope National Facility at Parkes and reveal a clear variability with two maxima at phases 0.0 (spot A) and 0.5 (spot B). Nearly simultaneous optical photometry can be modeled by a cool extended photospheric spot at the phase 0.0 (spot A). Simultaneous H-alpha photometry

  9. Opioid Peptidomimetics: Leads for the Design of Bioavailable Mixed Efficacy Mu Opioid Receptor (MOR) Agonist/Delta Opioid Receptor (DOR) Antagonist Ligands

    PubMed Central

    Mosberg, Henry I.; Yeomans, Larisa; Harland, Aubrie A.; Bender, Aaron M.; Sobczyk-Kojiro, Katarzyna; Anand, Jessica P.; Clark, Mary J.; Jutkiewicz, Emily M.; Traynor, John R.

    2013-01-01

    We have previously described opioid peptidomimetic, 1, employing a tetrahydroquinoline scaffold and modeled on a series of cyclic tetrapeptide opioid agonists. We have recently described modifications to these peptides that confer a mu opioid receptor (MOR) agonist, delta opioid receptor (DOR) antagonist profile, which has been shown to reduce the development of tolerance to the analgesic actions of MOR agonists. Several such bifunctional ligands have been reported, but none has been demonstrated to cross the blood brain barrier. Here we describe the transfer of structural features that evoked MOR agonist/DOR antagonist behavior in the cyclic peptides to the tetrahydroquinoline scaffold and show that the resulting peptidomimetics maintain the desired pharmacological profile. Further, the 4R diastereomer of 1 was fully efficacious and approximately equipotent to morphine in the mouse warm water tail withdrawal assay following intraperitoneal administration and thus a promising lead for the development of opioid analgesics with reduced tolerance. PMID:23419026

  10. Ab Initio Study of Polonium

    SciTech Connect

    Zabidi, Noriza Ahmad; Kassim, Hasan Abu; Shrivastava, Keshav N.

    2008-05-20

    Polonium is the only element with a simple cubic (sc) crystal structure. Atoms in solid polonium sit at the corners of a simple cubic unit cell and no where else. Polonium has a valence electron configuration 6s{sup 2}6p{sup 4} (Z = 84). The low temperature {alpha}-phase transforms into the rhombohedral (trigonal) {beta} structure at {approx}348 K. The sc {alpha}-Po unit cell constant is a = 3.345 A. The beta form of polonium ({beta}-Po) has the lattice parameters, a{sub R} = 3.359 A and a rhombohedral angle 98 deg. 13'. We have performed an ab initio electronic structure calculation by using the density functional theory. We have performed the calculation with and without spin-orbit (SO) coupling by using both the LDA and the GGA for the exchange-correlations. The k-points in a simple cubic BZ are determined by R (0.5, 0.5, 0.5), {gamma} (0, 0, 0), X (0.5, 0, 0), M (0.5, 0.5, 0) and {gamma} (0, 0, 0). Other directions of k-points are {gamma} (0, 0, 0), X (0.5, 0, 0), R (0.5, 0.5, 0.5) and {gamma} (0, 0, 0). The SO splittings of p states at the {gamma} point in the GGA+SO scheme for {alpha}-Po are 0.04 eV and 0.02 eV while for the {beta}-Po these are 0.03 eV and 0.97 eV. We have also calculated the vibrational spectra for the unit cells in both the structures. We find that exchanging of a Po atom by Pb atom produces several more bands and destabilizes the {beta} phase.

  11. Remote moving target indication assessment

    SciTech Connect

    Canavan, G.H.

    1996-10-01

    The objective of this project was to design and test key components of a sensor to be used on remotely piloted vehicles, aircraft, or satellites for the detection of moving vehicles in cluttered backgrounds. The proposed sensor uses modern large-array focal planes to provide multiple infrared observations of moving targets and capable on-board computers to integrate multiple observations to detect moving targets in background clutter. This combination reduces the size, weight, and cost of the sensor to levels that can be flown on many small unmanned platforms. This effort selected the actual components, integrated them into a test bed, tested the performance of the sensor against realistic generated scenes, and designed a proof-of-concept prototype.

  12. Move!

    ERIC Educational Resources Information Center

    Nicholls, Bronwen

    Designed as a practical guide for teachers, this handbook presents ways of introducing drama and movement into secondary school curricula. A basic program for a movement class is offered, based on three objectives: one's own movement, secondary or underlying motives, and the balance of freedom and discipline. In the first section of the book,…

  13. SEEDS Moving Group Status Update

    NASA Technical Reports Server (NTRS)

    McElwain, Michael

    2011-01-01

    I will summarize the current status of the SEEDS Moving Group category and describe the importance of this sub-sample for the entire SEEDS survey. This presentation will include analysis of the sensitivity for the Moving Groups with general a comparison to other the other sub-categories. I will discuss the future impact of the Subaru SCExAO system for these targets and the advantage of using a specialized integral field spectrograph. Finally, I will present the impact of a pupil grid mask in order to produce fiducial spots in the focal plane that can be used for both photometry and astrometry.

  14. Radiography of Chaotically Moving Objects

    SciTech Connect

    Vavrik, Daniel; Jandejsek, Ivan; Dammer, Jiri; Holy, Tomas; Jakubek, Jan; Jakubek, Martin

    2007-11-26

    Radiography of moving objects is an advanced problem when the dynamic range of acquired radiograms is restricted by a limited exposition time. Exposition time has to be short to avoid image blurring due to object moving. It is possible to increase the dynamic range by summing short time radiograms set when the periodical object movement is presented as in the case of heart beating for instance. On the other hand a non periodical movement can be studied using tools of X-ray Digital Image Correlation technique. Short time radiograms are fitted into corresponding positions and consequently summed for higher data statistics as it is presented in this work.

  15. Calibration of moving puncture simulations

    NASA Astrophysics Data System (ADS)

    Brügmann, Bernd; González, José A.; Hannam, Mark; Husa, Sascha; Sperhake, Ulrich; Tichy, Wolfgang

    2008-01-01

    We present single and binary black-hole simulations that follow the “moving-puncture” paradigm of simulating black-hole spacetimes without excision, and use “moving boxes” mesh refinement. Focusing on binary black-hole configurations where the simulations cover roughly two orbits, we address five major issues determining the quality of our results: numerical discretization error, finite extraction radius of the radiation signal, physical appropriateness of initial data, gauge choice, and computational performance. We also compare results we have obtained with the BAM code described here with the independent LEAN code.

  16. Metabolic Consequences of Infection of Grapevine (Vitis vinifera L.) cv. "Modra frankinja" with Flavescence Dorée Phytoplasma.

    PubMed

    Prezelj, Nina; Covington, Elizabeth; Roitsch, Thomas; Gruden, Kristina; Fragner, Lena; Weckwerth, Wolfram; Chersicola, Marko; Vodopivec, Maja; Dermastia, Marina

    2016-01-01

    Flavescence dorée, caused by the quarantine phytoplasma FDp, represents the most devastating of the grapevine yellows diseases in Europe. In an integrated study we have explored the FDp-grapevine interaction in infected grapevines of cv. "Modra frankinja" under natural conditions in the vineyard. In FDp-infected leaf vein-enriched tissues, the seasonal transcriptional profiles of 14 genes selected from various metabolic pathways showed an FDp-specific plant response compared to other grapevine yellows and uncovered a new association of the SWEET17a vacuolar transporter of fructose with pathogens. Non-targeted metabolome analysis from leaf vein-enriched tissues identified 22 significantly changed compounds with increased levels during infection. Several metabolites corroborated the gene expression study. Detailed investigation of the dynamics of carbohydrate metabolism revealed significant accumulation of sucrose and starch in the mesophyll of FDp-infected leaves, as well as significant up-regulation of genes involved in their biosynthesis. In addition, infected leaves had high activities of ADP-glucose pyrophosphorylase and, more significantly, sucrose synthase. The data support the conclusion that FDp infection inhibits phloem transport, resulting in accumulation of carbohydrates and secondary metabolites that provoke a source-sink transition and defense response status. PMID:27242887

  17. Hurricane Irene on the Move

    NASA Video Gallery

    GOES-13 satellite imagery in 15 minute intervals from August 25, 2011, at 9:40 a.m. EDT to August 27 at 9:40 a.m. EDT. The animations show Hurricane Irene moving through the Bahamas and making land...

  18. Experimental Introduction to Moving Bodies.

    ERIC Educational Resources Information Center

    Peterson, Lars Ostrup; Justesen, Uffe

    1996-01-01

    Presents a simple experiment--a marble rolling on a tilted desk--to introduce students to moving bodies. Makes difficult subjects such as measurement, calculus, modeling, and uncertainty easier to identify by putting them into a simple context. Discusses misconceptions, models, and measurements. (JRH)

  19. Planning for the Collection Move.

    ERIC Educational Resources Information Center

    Mitchell, Eugene S.

    When professional movers are hired to move a library collection, drawing up written specifications becomes the most important part of the planning process. Specifications explain exactly what needs to be done, form the basis for a legal contract, and provide the basis for determining the cost of the job. Precision is an important component of…

  20. Friction in a Moving Car

    ERIC Educational Resources Information Center

    Goldberg, Fred M.

    1975-01-01

    Describes an out-of-doors, partially unstructured experiment to determine the coefficient of friction for a moving car. Presents the equation which relates the coefficient of friction to initial velocity, distance, and time and gives sample computed values as a function of initial speed and tire pressure. (GS)

  1. Moving in a moving medium: new perspectives on flight.

    PubMed

    Shepard, Emily L C; Ross, Andrew N; Portugal, Steven J

    2016-09-26

    One of the defining features of the aerial environment is its variability; air is almost never still. This has profound consequences for flying animals, affecting their flight stability, speed selection, energy expenditure and choice of flight path. All these factors have important implications for the ecology of flying animals, and the ecosystems they interact with, as well as providing bio-inspiration for the development of unmanned aerial vehicles. In this introduction, we touch on the factors that drive the variability in airflows, the scales of variability and the degree to which given airflows may be predictable. We then summarize how papers in this volume advance our understanding of the sensory, biomechanical, physiological and behavioural responses of animals to air flows. Overall, this provides insight into how flying animals can be so successful in this most fickle of environments.This article is part of the themed issue 'Moving in a moving medium: new perspectives on flight'. PMID:27528772

  2. Moving belt radiator development status

    NASA Technical Reports Server (NTRS)

    White, K. Alan

    1988-01-01

    Development of the Moving Belt Radiator (MBR) as an advanced space radiator concept is discussed. The ralative merits of Solid Belt (SBR), Liquid Belt (LBR), and Hybrid Belt (HBR) Radiators are described. Analytical and experimental efforts related to the dynamics of a rotating belt in microgravity are reviewed. The development of methods for transferring heat to the moving belt is discussed, and the results from several experimental investigations are summarized. Limited efforts related to the belt deployment and stowage, and to fabrication of a hybrid belt, are also discussed. Life limiting factors such as seal wear and micrometeroid resistance are identified. The results from various MBR point design studies for several power levels are compared with advanced Heat Pipe Radiator technology. MBR designs are shown to compare favorable at both 300 and 1000 K temperature levels. However, additional effort will be required to resolve critical technology issues and to demonstrate the advantage of MBR systems.

  3. The moving mesh code SHADOWFAX

    NASA Astrophysics Data System (ADS)

    Vandenbroucke, B.; De Rijcke, S.

    2016-07-01

    We introduce the moving mesh code SHADOWFAX, which can be used to evolve a mixture of gas, subject to the laws of hydrodynamics and gravity, and any collisionless fluid only subject to gravity, such as cold dark matter or stars. The code is written in C++ and its source code is made available to the scientific community under the GNU Affero General Public Licence. We outline the algorithm and the design of our implementation, and demonstrate its validity through the results of a set of basic test problems, which are also part of the public version. We also compare SHADOWFAX with a number of other publicly available codes using different hydrodynamical integration schemes, illustrating the advantages and disadvantages of the moving mesh technique.

  4. Moved by a Rapid Transit

    NASA Astrophysics Data System (ADS)

    Bueter, C.

    2013-04-01

    Enticing by virtue of its predictability, historical utility, and spectacle, the transit of Venus is a niche event among astronomical phenomena. Though the value of a transit for scientific purposes is now diminished, the brief appearance of Venus silhouetted against the background of the Sun in 2004 moved the artistic community to celebrate the rare alignment. Artists of all ages combined old traditions with fresh technology to create a 21st-century tapestry of music, sculpture, paintings, glasswork, quilts, sky shows, and digital imagery. A full catalog of transit-related art generated over the centuries would feature the sampling of entries presented here and at the Moved by a Rapid Transit website.

  5. Ab interno trabeculectomy: patient selection and perspectives.

    PubMed

    Vinod, Kateki; Gedde, Steven J

    2016-01-01

    Ab interno trabeculectomy is one among several recently introduced minimally invasive glaucoma surgeries that avoid a conjunctival incision and full-thickness sclerostomy involved in traditional glaucoma surgery. Ablation of the trabecular meshwork and inner wall of Schlemm's canal is performed in an arcuate fashion via a clear corneal incision, alone or in combination with phacoemulsification cataract surgery. Intraocular pressure reduction following ab interno trabeculectomy is limited by resistance in distal outflow pathways and generally stabilizes in the mid-to-high teens. Relief of medication burden has been demonstrated by some studies. A very low rate of complications, most commonly transient hyphema and intraocular pressure elevations in the immediate postoperative period, have been reported. However, available data are derived from small retrospective and prospective case series. Randomized, controlled trials are needed to better elucidate the potential merits of ab interno trabeculectomy in the combined setting versus phacoemulsification cataract surgery alone and to compare it with other minimally invasive glaucoma surgeries. PMID:27574396

  6. Embodied Moving-Target Seeking with Prediction and Planning

    NASA Astrophysics Data System (ADS)

    Oses, Noelia; Hoffmann, Matej; Koene, Randal A.

    We present a bio-inspired control method for moving-target seeking with a mobile robot, which resembles a predator-prey scenario. The motor repertoire of a simulated Khepera robot was restricted to a discrete number of 'gaits'. After an exploration phase, the robot automatically synthesizes a model of its motor repertoire, acquiring a forward model. Two additional components were introduced for the task of catching a prey robot. First, an inverse model to the forward model, which is used to determine the action (gait) needed to reach a desired location. Second, while hunting the prey, a model of the prey's behavior is learned online by the hunter robot. All the models are learned ab initio, without assumptions, work in egocentric coordinates, and are probabilistic in nature. Our architecture can be applied to robots with any physical constraints (or embodiment), such as legged robots.

  7. Characterizing The Nearest Young Moving Groups Through High Resolution Spectroscopy

    NASA Astrophysics Data System (ADS)

    McCarthy, Kyle; Wilhelm, Ronald J.

    2015-01-01

    We present a detailed method for characterizing the nearest young moving groups via high resolution spectroscopy. This method has three diagnostics which classify a moving group: (1) Chemical Homogeneity, (2) Kinematic Traceback, and (3) Isochrone Fitting. We have applied this technique on 10 F- and G-type stars from the AB Doradus Moving Group (ABD) and found 8 stars share similar metal abundances with an average abundance for ABD of <[M/H]> = -0.03 ± 0.06; of the two outliers, one is metal rich and the other metal poor. Seven stars follow a common traceback and share a common origin around 125 Myr. One of the outlying traceback stars diverges around 90-100 Myr, and is the same star which is metal rich. Eight stars fall along the same isochrone of 100 Myr, which is synonymous with the main sequence. We further evaluated this technique on 5 members of the newly discovered Octans-Near Moving Group (ONMG). Two of these were listed as possible members with the other three being probable members. There is a large spread in the metal abundance with <[M/H]> = -0.17 ± 0.1 and no core group of stars that define the cluster in abundance space. ONMG is also enigmatic because several age indicators (e.g. lithium abundance, surface gravities, activity) indicate a much younger cluster; however, the traceback age shows these stars were closest around 150 Myr (though this age should be taken very lightly) and 4 of the 5 stars fall on the main sequence. We therefore conclude that while these stars do share present day velocities and positions, the group is not well defined in abundance, origin, or age, and should be concidered with caution.

  8. MELCOR 1.8.2 assessment: Aerosol experiments ABCOVE AB5, AB6, AB7, and LACE LA2

    SciTech Connect

    Souto, F.J.; Haskin, F.E.; Kmetyk, L.N.

    1994-10-01

    The MELCOR computer code has been used to model four of the large-scale aerosol behavior experiments conducted in the Containment System Test Facility (CSTF) vessel. Tests AB5, AB6 and AB7 of the ABCOVE program simulate the dry aerosol conditions during a hypothetical severe accident in an LMFBR. Test LA2 of the LACE program simulates aerosol behavior in a condensing steam environment during a postulated severe accident in an LWR with failure to isolate the containment. The comparison of code results to experimental data show that MELCOR is able to correctly predict most of the thermal-hydraulic results in the four tests. MELCOR predicts reasonably well the dry aerosol behavior of the ABCOVE tests, but significant disagreements are found in the aerosol behavior modelling for the LA2 experiment. These results tend to support some of the concerns about the MELCOR modelling of steam condensation onto aerosols expressed in previous works. During these analyses, a limitation in the MELCOR input was detected for the specification of the aerosol parameters for more than one component. A Latin Hypercube Sampling (LHS) sensitivity study of the aerosol dynamic constants is presented for test AB6. The study shows the importance of the aerosol shape factors in the aerosol deposition behavior, and reveals that MELCOR input/output processing is highly labor intensive for uncertainty and sensitivity analyses based on LHS.

  9. Characterization of mAb dimers reveals predominant dimer forms common in therapeutic mAbs.

    PubMed

    Plath, Friederike; Ringler, Philippe; Graff-Meyer, Alexandra; Stahlberg, Henning; Lauer, Matthias E; Rufer, Arne C; Graewert, Melissa A; Svergun, Dmitri; Gellermann, Gerald; Finkler, Christof; Stracke, Jan O; Koulov, Atanas; Schnaible, Volker

    2016-07-01

    The formation of undesired high molecular weight species such as dimers is an important quality attribute for therapeutic monoclonal antibody formulations. Therefore, the thorough understanding of mAb dimerization and the detailed characterization mAb dimers is of great interest for future pharmaceutical development of therapeutic antibodies. In this work, we focused on the analyses of different mAb dimers regarding size, surface properties, chemical identity, overall structure and localization of possible dimerization sites. Dimer fractions of different mAbs were isolated to a satisfactory purity from bulk material and revealed 2 predominant overall structures, namely elongated and compact dimer forms. The elongated dimers displayed one dimerization site involving the tip of the Fab domain. Depending on the stress applied, these elongated dimers are connected either covalently or non-covalently. In contrast, the compact dimers exhibited non-covalent association. Several interaction points were detected for the compact dimers involving the hinge region or the base of the Fab domain. These results indicate that mAb dimer fractions are rather complex and may contain more than one kind of dimer. Nevertheless, the overall appearance of mAb dimers suggests the existence of 2 predominant dimeric structures, elongated and compact, which are commonly present in preparations of therapeutic mAbs. PMID:27031922

  10. On the Nature of the Prototype Luminous Blue Variable Ag Carinae. I. Fundamental Parameters During Visual Minimum Phases and Changes in the Bolometric Luminosity During the S-Dor Cycle

    NASA Astrophysics Data System (ADS)

    Groh, J. H.; Hillier, D. J.; Damineli, A.; Whitelock, P. A.; Marang, F.; Rossi, C.

    2009-06-01

    We present a detailed spectroscopic analysis of the luminous blue variable (LBV) AG Carinae (AG Car) during the last two visual minimum phases of its S-Dor cycle (1985-1990 and 2000-2003). The analysis reveals an overabundance of He, N, and Na, and a depletion of H, C, and O, on the surface of the AG Car, indicating the presence of a CNO-processed material. Furthermore, the ratio N/O is higher on the stellar surface than in the nebula. We found that the minimum phases of AG Car are not equal to each other, since we derived a noticeable difference between the maximum effective temperature achieved during 1985-1990 (22, 800 K) and 2000-2001 (17,000 K). Significant differences between the wind parameters in these two epochs were also noticed. While the wind terminal velocity was 300 km s-1 in 1985-1990, it was as low as 105 km s-1 in 2001. The mass-loss rate, however, was lower from 1985-1990 (1.5 × 10-5 M sun yr-1) than from 2000-2001 (3.7 × 10-5 M sun yr-1). We found that the wind of AG Car is significantly clumped (f sime 0.10-0.25) and that clumps must be formed deep in the wind. We derived a bolometric luminosity of 1.5 × 106 L sun during both minimum phases which, contrary to the common assumption, decreases to 1.0 × 106 L sun as the star moves toward the maximum flux in the V band. Assuming that the decrease in the bolometric luminosity of AG Car is due to the energy used to expand the outer layers of the star, we found that the expanding layers contain roughly 0.6-2 M sun. Such an amount of mass is an order of magnitude lower than the nebular mass around AG Car, but is comparable to the nebular mass found around lower-luminosity LBVs and to that of the Little Homunculus of Eta Car. If such a large amount of mass is indeed involved in the S Dor-type variability, we speculate that such instability could be a failed Giant Eruption, with several solar masses never becoming unbound from the star. Based on observations made with the 1.6 m telescope at the

  11. Senior Living: Staying Positive and Moving Forward

    MedlinePlus

    ... Issues Feature: Senior Living Staying Positive and Moving Forward Past Issues / Summer 2009 Table of Contents For ... Living / Long Distance Caregiving / Staying Positive and Moving Forward / Former WWII Fighter Pilot Finds New Home Near ...

  12. Preparing Your Child for a Move

    MedlinePlus

    ... certificate, and medical records. previous continue Moving With Teens It's common for teens to actively rebel against a move. Your teen has probably invested considerable energy in a particular ...

  13. On the Strain Rate Sensitivity of Abs and Abs Plus Fused Deposition Modeling Parts

    NASA Astrophysics Data System (ADS)

    Vairis, A.; Petousis, M.; Vidakis, N.; Savvakis, K.

    2016-06-01

    In this work the effect of strain rate on the tensile strength of fused deposition modeling parts built with Acrylonitrile-butadiene-styrene (ABS) and ABS plus material is presented. ASTM D638-02a specimens were built with ABS and ABS plus and they were tested on a Schenck Trebel Co. tensile test machine at three different test speeds, equal, lower, and higher to the test speed required by the ASTM D638-02a standard. The experimental tensile strength results were compared and evaluated. The fracture surfaces of selected specimens were examined with a scanning electron microscope, to determine failure mode of the filament strands. It was found that, as the test speed increases, specimens develop higher tensile strength and have higher elastic modulus. Specimens tested in the highest speed of the experiment had on average about 10% higher elastic modulus and developed on average about 11% higher tensile strength.

  14. Rapid digestion of Cry34Ab1 and Cry35Ab1 in simulated gastric fluid.

    PubMed

    Herman, Rod A; Schafer, Barry W; Korjagin, Valerie A; Ernest, April D

    2003-11-01

    Two genes were identified in Bacillus thuringiensis Berliner (Bt) that code for the proteins that comprise a Cry34Ab1/Cry35Ab1 binary insecticidal crystal protein. Maize, Zea mays L., plants have been transformed to express the Cry34Ab1/Cry35Ab1 proteins, and as a result, these plants are resistant to attack by western corn rootworm, Diabrotica virgifera virgifera LeConte, a major pest in the Midwestern corn-growing area of the U.S.A. As part of the safety assessment for the proteins, digestibility studies were conducted. Digestion experiments with both proteins demonstrated rapid degradation in simulated gastric fluid, comparable to other registered plant-incorporated protectants. Quantitative and qualitative approaches for determining digestibility are illustrated. PMID:14582981

  15. Microscopic features of moving traffic jams

    NASA Astrophysics Data System (ADS)

    Kerner, Boris S.; Klenov, Sergey L.; Hiller, Andreas; Rehborn, Hubert

    2006-04-01

    Empirical and numerical microscopic features of moving traffic jams are presented. Based on a single vehicle data analysis, it is found that within wide moving jams, i.e., between the upstream and downstream jam fronts there is a complex microscopic spatiotemporal structure. This jam structure consists of alternations of regions in which traffic flow is interrupted and flow states of low speeds associated with “moving blanks” within the jam. Moving blanks within a wide moving jam resemble electron holes in the valence band of semiconductors: As the moving blanks that propagate upstream appear due to downstream vehicle motion within the jam, so appearance of electron holes moving with the electric field results from electron motion against the electric field in the valence band of semiconductors. Empirical features of moving blanks are found. Based on microscopic models in the context of the Kerner’s three-phase traffic theory, physical reasons for moving blanks emergence within wide moving jams are disclosed. Microscopic nonlinear effects of moving jam emergence, propagation, and dissolution as well as a diverse variety of hysteresis effects in freeway traffic associated with phase transitions and congested traffic propagation are numerically investigated. Microscopic structure of moving jam fronts is numerically studied and compared with empirical results.

  16. Palaeoseismic events recorded in Archaean gold-quartz vein networks, Val d'Or, Abitibi, Quebec, Canada

    NASA Astrophysics Data System (ADS)

    Boullier, Anne-Marie; Robert, François

    1992-02-01

    Archaean gold-quartz vein deposits are commonly hosted in high-angle reverse shear zones and are interpreted to have formed in a regime of horizontal compression and high fluid pressure environment. This paper presents the results of a combined structural and fluid inclusion study on three gold-quartz vein deposits of the Val d'Or area (Abitibi, Quebec) consisting of subhorizontal extensional veins and E-W steeply dipping shear veins. Crack-seal structures, tourmaline fibres, stretched quartz crystals and open-space filling textures indicate that the subhorizontal veins formed by hydraulic fracturing under supralithostatic fluid pressure. CO 2-rich and H 2O + NaCl fluid inclusions, interpreted as two coexisting immiscible fluids, occur typically in microcracks of different orientations interpreted to have formed in the σ1- σ2 plane. Horizontal CO 2-rich fluid inclusion planes are contemporaneous with the opening of these veins (σ 3 vertical). Vertical H 2O + NaCl fluid inclusion planes, as well as some microstructures, such as deformed minerals, indicate that the same extensional veins have experienced episodic vertical shortening (σ 3 horizontal) alternating with the opening events. Deformation and slip/opening also occurred in shear veins in which preferred orientation of fluid inclusion planes is not clear, except that the H 2O + NaCl fluid inclusion planes tend to be oriented at high angles to the slip direction. The successive opening and collapse events in subhorizontal extensional veins are correlated with deformation and slip/opening events in shear veins, respectively, and are attributed to cyclic fluid pressure fluctuations in the system. They are thus consistent with the fault-valve model: sudden drop in fluid pressure from supralithostatic to lower values induces fluid unmixing and occurs immediately post-failure following seismic rupturing along the shear zone. Sealing of the shear veins allows the fluid pressure to build up again and the

  17. Collision detection for moving polyhedra.

    PubMed

    Canny, J

    1986-02-01

    We consider the collision-detection problem for a three-dimensional solid object moving among polyhedral obstacles. The configuration space for this problem is six-dimensional, and the traditional representation of the space uses three translational parameters and three angles (typically Euler angles). The constraints between the object and obstacles then involve trigonometric functions. We show that a quaternion representation of rotation yields constraints which are purely algebraic in a seven-dimensional space. By simple manipulation, the constraints may be projected down into a six-dimensional space with no increase in complexity. The algebraic form of the constraints greatly simplifies computation of collision points, and allows us to derive an efficient exact intersection test for an object which is translating and rotating among obstacles. PMID:21869338

  18. Moving frames and prolongation algebras

    NASA Technical Reports Server (NTRS)

    Estabrook, F. B.

    1982-01-01

    Differential ideals generated by sets of 2-forms which can be written with constant coefficients in a canonical basis of 1-forms are considered. By setting up a Cartan-Ehresmann connection, in a fiber bundle over a base space in which the 2-forms live, one finds an incomplete Lie algebra of vector fields in the fields in the fibers. Conversely, given this algebra (a prolongation algebra), one can derive the differential ideal. The two constructs are thus dual, and analysis of either derives properties of both. Such systems arise in the classical differential geometry of moving frames. Examples of this are discussed, together with examples arising more recently: the Korteweg-de Vries and Harrison-Ernst systems.

  19. DOR – a Database of Olfactory Receptors – Integrated Repository for Sequence and Secondary Structural Information of Olfactory Receptors in Selected Eukaryotic Genomes

    PubMed Central

    Nagarathnam, Balasubramanian; Karpe, Snehal D; Harini, Krishnan; Sankar, Kannan; Iftekhar, Mohammed; Rajesh, Durairaj; Giji, Sadasivam; Archunan, Govidaraju; Balakrishnan, Veluchamy; Gromiha, M Michael; Nemoto, Wataru; Fukui, Kazhuhiko; Sowdhamini, Ramanathan

    2014-01-01

    Olfaction is the response to odors and is mediated by a class of membrane-bound proteins called olfactory receptors (ORs). An understanding of these receptors serves as a good model for basic signal transduction mechanisms and also provides important clues for the strategies adopted by organisms for their ultimate survival using chemosensory perception in search of food or defense against predators. Prior research on cross-genome phylogenetic analyses from our group motivated the addressal of conserved evolutionary trends, clustering, and ortholog prediction of ORs. The database of olfactory receptors (DOR) is a repository that provides sequence and structural information on ORs of selected organisms (such as Saccharomyces cerevisiae, Drosophila melanogaster, Caenorhabditis elegans, Mus musculus, and Homo sapiens). Users can download OR sequences, study predicted membrane topology, and obtain cross-genome sequence alignments and phylogeny, including three-dimensional (3D) structural models of 100 selected ORs and their predicted dimer interfaces. The database can be accessed from http://caps.ncbs.res.in/DOR. Such a database should be helpful in designing experiments on point mutations to probe into the possible dimerization modes of ORs and to even understand the evolutionary changes between different receptors. PMID:25002814

  20. Cloning proenkephalin from the brain of a urodele amphibian (Taricha granulosa) using a DOR-specific primer in a 3'RACE reaction.

    PubMed

    Walthers, Eliza A; Moore, Frank L

    2005-07-01

    A large cDNA fragment that codes for proenkephalin (PENK) was cloned from the rough-skinned newt, Taricha granulosa (GenBank Accession: AY817670). This 1299-bp PENK cDNA extends from the poly(A) sequence on the 3' end into the 5'-UTR (221bp) upstream of an open reading frame that codes for 264 amino acids and a stop codon. Within the precursor are five Met-enkephalin sequences and two C-terminally extended forms of Met-enkephalin (YGGFMRGV and YGGFMRY). The organization of the opioid core sequences within the newt PENK closely resembles that reported for other vertebrates. In this urodele amphibian, as in anurans, PENK does not contain the penultimate Leu-enkephalin opioid sequence found in mammals, and instead has in this position Met-enkephalin. PENK cDNA was amplified from newt brain in a RACE PCR targeting the 3' end of the newt delta opioid receptor (DOR). It remains to be determined whether generating the cDNA for the newt PENK while cloning its receptor was serendipitous or the result of a meaningful coincidence between the DOR and PENK sequences. PMID:15935163

  1. The BANYAN All-Sky Survey for Brown Dwarf Members of Young Moving Groups

    NASA Astrophysics Data System (ADS)

    Gagné, Jonathan; Lafrenière, David; Doyon, René; Faherty, Jacqueline K.; Malo, Lison; Cruz, Kelle L.; Artigau, Étienne; Burgasser, Adam J.; Naud, Marie-Eve; Bouchard, Sandie; Gizis, John E.; Albert, Loïc

    2016-01-01

    We describe in this work the BASS survey for brown dwarfs in young moving groups of the solar neighborhood, and summarize the results that it generated. These include the discovery of the 2MASS J01033563-5515561 (AB)b and 2MASS J02192210-3925225 B young companions near the deuterium-burning limit as well as 44 new low-mass stars and 69 new brown dwarfs with a spectroscopically confirmed low gravity. Among those, ~20 have estimated masses within the planetary regime, one is a new L4 γ bona fide member of AB Doradus, three are TW Hydrae candidates with later spectral types (L1-L4) than all of its previously known members and six are among the first contenders for low-gravity >= L5 β/γ brown dwarfs, reminiscent of WISEP J004701.06+680352.1, PSO J318.5338-22.8603 and VHS J125601.92-125723.9 b. Finally, we describe a future version of this survey, BASS-Ultracool, that will specifically target >= L5 candidate members of young moving groups. First experimentations in designing the survey have already led to the discovery of a new T dwarf bona fide member of AB Doradus, as well as the serendipitous discoveries of an L9 subdwarf and an L5 + T5 brown dwarf binary.

  2. Collective rotation from ab initio theory

    NASA Astrophysics Data System (ADS)

    Caprio, Mark A.; Maris, Pieter; Vary, James P.

    2015-10-01

    The challenge of ab initio nuclear theory is to quantitatively predict the complex and highly-correlated behavior of the nuclear many-body system, starting from the underlying internucleon interactions. We may now seek to understand the wealth of nuclear collective phenomena through ab initio approaches. No-core configuration interaction (NCCI) calculations for p-shell nuclei give rise to rotational bands, as evidenced by rotational patterns for excitation energies, electromagnetic moments, and electromagnetic transitions. In this talk, the intrinsic structure of these bands is discussed, and the predicted rotational bands are compared to experiment. Supported by the US DOE under Award Nos. DE-FG02-95ER-40934, DESC0008485 (SciDAC/NUCLEI), and DE-FG02-87ER40371 and the US NSF under Award No. 0904782. Computational resources provided by NERSC (US DOE Contract No. DE-AC02-05CH11231).

  3. Ab initio infrared and Raman spectra

    NASA Technical Reports Server (NTRS)

    Fredkin, D. R.; White, S. R.; Wilson, K. R.; Komornicki, A.

    1983-01-01

    It is pointed out that with increased computer power and improved computational techniques, such as the gradients developed in recent years, it is becoming practical to compute spectra ab initio, from the fundamental constants of nature, for systems of increasing complexity. The present investigation has the objective to explore several possible ab initio approaches to spectra, giving particular attention to infrared and nonresonance Raman. Two approaches are discussed. The sequential approach, in which first the electronic part and then later the nuclear part of the Born-Oppenheimer approximation is solved, is appropriate for small systems. The simultaneous approach, in which the electronic and nuclear parts are solved at the same time, is more appropriate for many-atom systems. A review of the newer quantum gradient techniques is provided, and the infrared and Raman spectral band contours for the water molecule are computed.

  4. Interaction of vermiculite with Katamin AB

    SciTech Connect

    Veksler, V.I.; Makashev, Yu.A.; Mikhailova, V.N.; Aleksandrova, E.M.; Vinogradova, I.A.

    1986-12-10

    Vermiculite can interact with quaternary ammonium salts to form organmineral compounds in the ion-exchange adsorption of these salts from waste water. This paper investigates this interaction between vermiculite and Katamin AB, a commercial cationic surfactant consisting of an aqueous solution of alkylbenyldimethylammonium chloride homologs. It is shown that ion exchange and molecular sorption occur simultaneously during the interaction and that vermiculite is a highly effective adsorbent in process water purification.

  5. Ab initio vel ex eventu. II

    NASA Astrophysics Data System (ADS)

    Thiessen, P. A.; Treder, H.-J.

    Jedes initium wird durch experimenta crucis zum eventus. Jedes theoretisch interpretierbare ex-eventu-Resultat führt auf ein neues Initium. Gerade dies ist die gemeinsame Aussage von Atomistik, Quantenmechanik und Relativitätstheorie.Translated AbstractAb initio vel ex eventu. IIEvery initium becomes an eventus by experimenta crucis. Every theoretically interpretable ex-eventu result leads to a new initium. Right this is the joint assertion of atomism, quantum mechanics, and relativity.

  6. Ab initio Bogoliubov coupled cluster theory

    NASA Astrophysics Data System (ADS)

    Signoracci, Angelo; Hagen, Gaute; Duguet, Thomas

    2014-09-01

    Coupled cluster (CC) theory has become a standard method in nuclear theory for realistic ab initio calculations of medium mass nuclei, but remains limited by its requirement of a Slater determinant reference state which reasonably approximates the nuclear system of interest. Extensions of the method, such as equation-of-motion CC, permit the calculation of nuclei with one or two nucleons added or removed from a doubly magic core, yet still only a few dozen nuclei are accessible with modern computational restrictions. In order to extend the applicability of ab initio methods to open-shell systems, the superfluid nature of nuclei must be taken into account. By utilizing Bogoliubov algebra and employing spontaneous symmetry breaking with respect to particle number conservation, superfluid systems can be treated by a single reference state. An ab initio theory to include correlations on top of a Bogoliubov reference state has been developed in the guise of standard CC theory. The formalism and first results of this Bogoliubov coupled cluster theory will be presented to demonstrate the applicability of the method.

  7. Ab interno trabeculectomy: patient selection and perspectives

    PubMed Central

    Vinod, Kateki; Gedde, Steven J

    2016-01-01

    Ab interno trabeculectomy is one among several recently introduced minimally invasive glaucoma surgeries that avoid a conjunctival incision and full-thickness sclerostomy involved in traditional glaucoma surgery. Ablation of the trabecular meshwork and inner wall of Schlemm’s canal is performed in an arcuate fashion via a clear corneal incision, alone or in combination with phacoemulsification cataract surgery. Intraocular pressure reduction following ab interno trabeculectomy is limited by resistance in distal outflow pathways and generally stabilizes in the mid-to-high teens. Relief of medication burden has been demonstrated by some studies. A very low rate of complications, most commonly transient hyphema and intraocular pressure elevations in the immediate postoperative period, have been reported. However, available data are derived from small retrospective and prospective case series. Randomized, controlled trials are needed to better elucidate the potential merits of ab interno trabeculectomy in the combined setting versus phacoemulsification cataract surgery alone and to compare it with other minimally invasive glaucoma surgeries. PMID:27574396

  8. Ab-inition melting curve of titanium

    NASA Astrophysics Data System (ADS)

    Stutzmann, Vincent; Bouchet, Johann; Bottin, Francois

    2014-03-01

    Thermodynamical properties of titanium are of great interest for aerospace and aviation industries and many studies are done in order to understand its behaviour under pressure (P) and temperature (T) : phase transitions at low T, melting curve at high T and P. In this work we compute the first ab-initio melting curve of titanium. This one is obtained with the Abinit package using DFT, in the GGA approximation, and in the framework of the projector augmented wave method (PAW). At first, we perform ground state calculations and study the five allotropic phases of titanium. Two PAW atomic data are generated with two different cutoff radius. The larger one gives results near previews ab-initio calculations, whereas the smaller one gives results near all electron calculation. Using the second PAW atomic data and performing ab-initio molecular dynamic simulations, we then compute the melting curve of titanium with three different methods. Results show relevance of our calculations, but also discrepencies with experimental data.

  9. Method and apparatus for a combination moving bed thermal treatment reactor and moving bed filter

    SciTech Connect

    Badger, Phillip C.; Dunn, Jr., Kenneth J.

    2015-09-01

    A moving bed gasification/thermal treatment reactor includes a geometry in which moving bed reactor particles serve as both a moving bed filter and a heat carrier to provide thermal energy for thermal treatment reactions, such that the moving bed filter and the heat carrier are one and the same to remove solid particulates or droplets generated by thermal treatment processes or injected into the moving bed filter from other sources.

  10. Leadership in Moving Human Groups

    PubMed Central

    Boos, Margarete; Pritz, Johannes; Lange, Simon; Belz, Michael

    2014-01-01

    How is movement of individuals coordinated as a group? This is a fundamental question of social behaviour, encompassing phenomena such as bird flocking, fish schooling, and the innumerable activities in human groups that require people to synchronise their actions. We have developed an experimental paradigm, the HoneyComb computer-based multi-client game, to empirically investigate human movement coordination and leadership. Using economic games as a model, we set monetary incentives to motivate players on a virtual playfield to reach goals via players' movements. We asked whether (I) humans coordinate their movements when information is limited to an individual group member's observation of adjacent group member motion, (II) whether an informed group minority can lead an uninformed group majority to the minority's goal, and if so, (III) how this minority exerts its influence. We showed that in a human group – on the basis of movement alone – a minority can successfully lead a majority. Minorities lead successfully when (a) their members choose similar initial steps towards their goal field and (b) they are among the first in the whole group to make a move. Using our approach, we empirically demonstrate that the rules of swarming behaviour apply to humans. Even complex human behaviour, such as leadership and directed group movement, follow simple rules that are based on visual perception of local movement. PMID:24699264

  11. Flow visualization using moving textures

    SciTech Connect

    Max, N.; Becker, B.

    1995-04-01

    An intuitive way to visualize a flow is to watch particles or textures move in the flow. In this paper, the authors show how texture mapping hardware can produce near-real-time texture motion, using a polygon grid, and one fixed texture. However, the authors make no attempt to indicate the flow direction in a still frame. As discussed here, any anisotropic stretching comes from the velocity gradient, not the velocity itself. The basic idea is to advect the texture by the flow field. In a cited paper, they gave an indication of the wind velocity by advecting the 3D texture coordinates on the polygon vertices of a cloudiness contour surface in a climate simulation. This was slow, because the 3D texture was rendered in software, and because advecting the texture was difficult for time-varying flows. In this paper, they replace the 3D textures by 2D texture maps compatible with hardware rendering, and give techniques for handling time-varying flows more efficiently. The next section gives their technique for the case of 2D steady flows, and the following one discusses the problems of texture distortion. Then they discuss the problems with extending method to time-varying flows, and two solutions. Next they develop compositing methods for visualizing 3D flows. The final section gives their results and conclusions.

  12. Gene therapy on the move

    PubMed Central

    Kaufmann, Kerstin B; Büning, Hildegard; Galy, Anne; Schambach, Axel; Grez, Manuel

    2013-01-01

    The first gene therapy clinical trials were initiated more than two decades ago. In the early days, gene therapy shared the fate of many experimental medicine approaches and was impeded by the occurrence of severe side effects in a few treated patients. The understanding of the molecular and cellular mechanisms leading to treatment- and/or vector-associated setbacks has resulted in the development of highly sophisticated gene transfer tools with improved safety and therapeutic efficacy. Employing these advanced tools, a series of Phase I/II trials were started in the past few years with excellent clinical results and no side effects reported so far. Moreover, highly efficient gene targeting strategies and site-directed gene editing technologies have been developed and applied clinically. With more than 1900 clinical trials to date, gene therapy has moved from a vision to clinical reality. This review focuses on the application of gene therapy for the correction of inherited diseases, the limitations and drawbacks encountered in some of the early clinical trials and the revival of gene therapy as a powerful treatment option for the correction of monogenic disorders. PMID:24106209

  13. Leadership in moving human groups.

    PubMed

    Boos, Margarete; Pritz, Johannes; Lange, Simon; Belz, Michael

    2014-04-01

    How is movement of individuals coordinated as a group? This is a fundamental question of social behaviour, encompassing phenomena such as bird flocking, fish schooling, and the innumerable activities in human groups that require people to synchronise their actions. We have developed an experimental paradigm, the HoneyComb computer-based multi-client game, to empirically investigate human movement coordination and leadership. Using economic games as a model, we set monetary incentives to motivate players on a virtual playfield to reach goals via players' movements. We asked whether (I) humans coordinate their movements when information is limited to an individual group member's observation of adjacent group member motion, (II) whether an informed group minority can lead an uninformed group majority to the minority's goal, and if so, (III) how this minority exerts its influence. We showed that in a human group--on the basis of movement alone--a minority can successfully lead a majority. Minorities lead successfully when (a) their members choose similar initial steps towards their goal field and (b) they are among the first in the whole group to make a move. Using our approach, we empirically demonstrate that the rules of swarming behaviour apply to humans. Even complex human behaviour, such as leadership and directed group movement, follow simple rules that are based on visual perception of local movement. PMID:24699264

  14. [Visual illusions and moving horizon].

    PubMed

    Zhdan'ko, I M; Chulaevskiĭ, A O; Kovalenko, P A

    2012-09-01

    Results of psychological "additional investigation" of the crash of Boeing-737, "Aeroflot-Nord" on 14.09.2008 near Perm are presented. 37 pilots from the one of the leading airline companies sensed the attitude and rolling out the aircraft to the forward flight under the moving horizon with straight display of bank and tangage (view from the aircraft to the ground) in model conditions. 29 pilots (78.4%) made a mistake at determining the roll direction and tangage, they made a mistake at determining the roll direction 61 times (16.4%) and 44 times at determining the tangage direction, in other words they confused left and right bank and also nose-up and nose-down. Visual illusions of mobility of space and handling of ground (instead of aircraft) during the flight were revealed in pilots. These illusions may be the important cause of the following crashes. The necessity of "back" faultless display of bank in all aircrafts of civil aviation and development of computer complex for training of visual spatial orientation is proved. PMID:23156114

  15. Range Imaging without Moving Parts

    NASA Technical Reports Server (NTRS)

    Blair, J. Bryan; Scott, V. Stanley, III; Ramos-Izquierdo, Luis

    2008-01-01

    Range-imaging instruments of a type now under development are intended to generate the equivalent of three-dimensional images from measurements of the round-trip times of flight of laser pulses along known directions. These instruments could also provide information on characteristics of targets, including roughnesses and reflectivities of surfaces and optical densities of such semi-solid objects as trees and clouds. Unlike in prior range-imaging instruments based on times of flight along known directions, there would be no moving parts; aiming of the laser beams along the known directions would not be accomplished by mechanical scanning of mirrors, prisms, or other optical components. Instead, aiming would be accomplished by using solid-state devices to switch input and output beams along different fiber-optic paths. Because of the lack of moving parts, these instruments could be extraordinarily reliable, rugged, and long-lasting. An instrument of this type would include an optical transmitter that would send out a laser pulse along a chosen direction to a target. An optical receiver coaligned with the transmitter would measure the temporally varying intensity of laser light reflected from the target to determine the distance and surface characteristics of the target. The transmitter would be a combination of devices for generating precise directional laser illumination. It would include a pulsed laser, the output of which would be coupled into a fiber-optic cable with a fan-out and solid-state optical switches that would enable switching of the laser beam onto one or more optical fibers terminated at known locations in an array on a face at the focal plane of a telescope. The array would be imaged by the telescope onto the target space. The receiver optical system could share the aforementioned telescope with the transmitter or could include a separate telescope aimed in the same direction as that of the transmitting telescope. In either case, light reflected

  16. Imagine Moving Off the Planet

    NASA Technical Reports Server (NTRS)

    Elfrey, Priscilla R.

    2006-01-01

    Moving off the planet will be a defining moment of this century as landing on the Moon was in the last. For that to happen for humans to go where humans cannot go-- simulation is the sole solution. NASA supports simulation for life-cycle activities: design, analysis, test, checkout, operations, review and training. We contemplate time spans of a century and more, teams dispersed to different planets and the need for systems that endure or adapt as missions, teams and technology change. Without imagination such goals are impossible. But with imagination we can go outside our present perception of reality to think about and take action on what has been, is and, especially, what might be. Consciously maturing an imagined, possibly workable, idea through framing it to optimization to design, and building the product provides us with a new approach to innovation and simulation fidelity. We address options, analyze, test and make improvements in how we think and work. Each step includes increasingly exact information about costs, schedule, who will be needed, where, when and how. NASA i integrating such thinking into its Exploration Product Realization Hierarchy for simulation and analysis, test and verification, and stimulus response goals. Technically NASA follows a timeline of studies, analysis, definition, design, development and operations with concurrent documentation. We have matched this Product Realization Hierarchy with a continuum from image to realization that incorporates commitment, current and needed research and communication to ensure superior and creative problem solving as well as advances in simulation. One result is a new approach to collaborative systems. Another is a distributed observer network prototyped using game engine technology bringing advanced 3-D simulation of a simulation to the desktop enabling people to develop shared consensus of its meaning. Much of the value of simulation comes from developing in people their ability to make good

  17. Microscale hydrodynamics near moving contact lines

    NASA Technical Reports Server (NTRS)

    Garoff, Stephen; Chen, Q.; Rame, Enrique; Willson, K. R.

    1994-01-01

    The hydrodynamics governing the fluid motions on a microscopic scale near moving contact lines are different from those governing motion far from the contact line. We explore these unique hydrodynamics by detailed measurement of the shape of a fluid meniscus very close to a moving contact line. The validity of present models of the hydrodynamics near moving contact lines as well as the dynamic wetting characteristics of a family of polymer liquids are discussed.

  18. Polymorphic Ab protofilaments exhibit distinct conformational dynamics as calculated by normal mode analysis

    NASA Astrophysics Data System (ADS)

    Armbruster, Matthew; Soto, Patricia

    2012-02-01

    This project proposes to test the hypothesis that the physicochemical milieu modulates the conformational dynamics of synthetic Alzheimer's Ab protofilament structures, the main component of Alzheimer's senile plaques. To this end, 3D solid-state NMR structures of Ab protofilaments were used as initial structures for molecular dynamics simulations in explicit water and a water/hexane environment. The initial structures of the simulations and representative structures from the simulation-generated trajectories were taken to perform computational normal mode analysis. We developed a code in python with a graphical user-friendly interface. The program incorporated the ProDy (0.7.1) package. With the application, we examined cross-correlation plots of Ca positions of the 2-fold Ab protofilaments along the most collective mode and the slowest mode. The protofilament structures were highly correlated in the water environment. We hypothesized the protofilament would move as one in water because of the viscosity. The square fluctuation of Ca positions was calculated for the slowest mode for the hexane model and the MD generated ensemble. The two plots match up until midway through the structure. At the midway point a phase shift emerged between the two structures most likely where the surrounding changes. The in-house developed code made it easy to perform analysis and will be used by other students in the research group.

  19. Undoing Gender Through Legislation and Schooling: the Case of AB 537 and AB 394 IN California, USA

    NASA Astrophysics Data System (ADS)

    Knotts, Greg

    2009-11-01

    This article investigates California laws AB 537: The Student Safety and Violence Prevention Act of 2000, and the recently enacted AB 394: Safe Place to Learn Act. Both demand that gender identity and sexual orientation be added to the lexicon of anti-harassment protection in public education. However, despite these progressive measures, schools have an unconscious acceptance of heteronormativity and gendered norms, which undermines both the spirit and language of these laws. This paper examines how California schools can both change standard practices and realise the transformative social change that laws like AB 537 and AB 394 can instigate. I assert that the systemic implementation of these laws, through the adoption, enforcement and evaluation of existing AB 537 Task Force Recommendations, is necessary for their success. My second assertion is that AB 537 and AB 394 have the potential to change and reconstitute gender-based and heteronormative standards at school sites.

  20. THE TUCANA/HOROLOGIUM, COLUMBA, AB DORADUS, AND ARGUS ASSOCIATIONS: NEW MEMBERS AND DUSTY DEBRIS DISKS

    SciTech Connect

    Zuckerman, B.; Rhee, Joseph H.; Song, Inseok; Bessell, M. S. E-mail: rhee@astro.ucla.edu E-mail: bessell@mso.anu.edu.au

    2011-05-10

    We propose 35 star systems within {approx}70 pc of Earth as newly identified members of nearby young stellar kinematic groups; these identifications include the first A- and late-B-type members of the AB Doradus moving group and field Argus Association. All but one of the 35 systems contain a bright solar- or earlier-type star that should make an excellent target for the next generation of adaptive optics (AO) imaging systems on large telescopes. AO imaging has revealed four massive planets in orbit around the {lambda} Boo star HR 8799. Initially, the planets were of uncertain mass due in large part to the uncertain age of the star. We find that HR 8799 is a likely member of the {approx}30 Myr old Columba Association, implying planet masses {approx}6 times that of Jupiter. We consider Spitzer Space Telescope MIPS photometry of stars in the {approx}30 Myr old Tucana/Horologium and Columba Associations, the {approx}40 Myr old field Argus Association, and the {approx}70 Myr old AB Doradus moving group. The percentage of stars in these young stellar groups that display excess emission above the stellar photosphere at 24 and 70 {mu}m wavelengths-indicative of the presence of a dusty debris disk-is compared with corresponding percentages for members of 11 open clusters and stellar associations with ages between 8 and 750 Myr, thus elucidating the decay of debris disks with time.

  1. 40 CFR 174.506 - Bacillus thuringiensis Cry34Ab1 and Cry35Ab1 proteins in corn; exemption from the requirement of...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Cry35Ab1 proteins in corn; exemption from the requirement of a tolerance. 174.506 Section 174.506... thuringiensis Cry34Ab1 and Cry35Ab1 proteins in corn; exemption from the requirement of a tolerance. Residues of Bacillus thuringiensis Cry34Ab1 and Cry35Ab1 proteins in corn are exempted from the requirement of...

  2. 40 CFR 174.506 - Bacillus thuringiensis Cry34Ab1 and Cry35Ab1 proteins in corn; exemption from the requirement of...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Cry35Ab1 proteins in corn; exemption from the requirement of a tolerance. 174.506 Section 174.506... thuringiensis Cry34Ab1 and Cry35Ab1 proteins in corn; exemption from the requirement of a tolerance. Residues of Bacillus thuringiensis Cry34Ab1 and Cry35Ab1 proteins in corn are exempted from the requirement of...

  3. 40 CFR 174.506 - Bacillus thuringiensis Cry34Ab1 and Cry35Ab1 proteins in corn; exemption from the requirement of...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Cry35Ab1 proteins in corn; exemption from the requirement of a tolerance. 174.506 Section 174.506... thuringiensis Cry34Ab1 and Cry35Ab1 proteins in corn; exemption from the requirement of a tolerance. Residues of Bacillus thuringiensis Cry34Ab1 and Cry35Ab1 proteins in corn are exempted from the requirement of...

  4. 40 CFR 174.506 - Bacillus thuringiensis Cry34Ab1 and Cry35Ab1 proteins in corn; exemption from the requirement of...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Cry35Ab1 proteins in corn; exemption from the requirement of a tolerance. 174.506 Section 174.506... thuringiensis Cry34Ab1 and Cry35Ab1 proteins in corn; exemption from the requirement of a tolerance. Residues of Bacillus thuringiensis Cry34Ab1 and Cry35Ab1 proteins in corn are exempted from the requirement of...

  5. Ab initio melting curve of osmium

    NASA Astrophysics Data System (ADS)

    Burakovsky, L.; Burakovsky, N.; Preston, D. L.

    2015-11-01

    The melting curve of osmium up to a pressure P of 500 GPa is obtained from an extensive suite of ab initio quantum molecular dynamics (QMD) simulations using the Z method. The ab initio P =0 melting point of Os is 3370 ±75 K; this range encompasses all of the available data in the literature and corroborates the conclusion of J. W. Arblaster [Platinum Metals Rev. 49, 166 (2005)], 10.1595/147106705X70264 that the melting temperature of pure Os is 3400 ±50 K and that the 3300 K typically quoted in the literature is the melting point of impure Os. The T =0 equation of state (EOS) of Os and the P dependence of the optimized c /a ratio for the hexagonal unit cell, both to pressures ˜900 GPa, are obtained in the ab initio approach as validation of its use. Although excellent agreement with the available experimental data (P ≲80 GPa) is found, it is the third-order Birch-Murnaghan EOS with B0'=5 rather than the more widely accepted B0'=4 that describes the QMD data to higher pressures, in agreement with the more recent experimental EOS by Godwal et al. The theoretical melting curve of Os obtained earlier by Joshi et al. is shown to be inconsistent with our QMD results, and the possible reason for this discrepancy is suggested. Regularities in the melting curves of Os and five other third-row transition metals (Ta, W, Re, Pt, Au) could be used to estimate the currently unknown melting curves of Hf and Ir.

  6. New challenges to medicare beneficiary access to mAbs

    PubMed Central

    Wilson, Andrew

    2009-01-01

    Precision binding of monoclonal antibodies (mAbs) to biological targets, their relative clinical success, and expansion of indications following initial approval, are distinctive clinical features. The relatively high cost of mAbs, together with the absence of a regulatory pathway to generics, stand out as distinctive economic features. Based on both literature review and primary data collection we enumerated mAb original approvals, supplemental indications and off-label uses, assessed payer formulary management of mAbs, and determined new challenges to Medicare beneficiary access to mAbs. We found that the FDA has approved 22 mAbs and 30 supplemental indications pertaining to the originally approved mAbs. In addition, there are 46 off-label use citations in officially recognized pharmaceutical compendia. Across Part B carriers and Part D plans, we found considerable variation in terms of coverage and conditions of reimbursement related to on- and off-label uses of mAbs. Our results point to four major challenges facing mAb developers, health care providers, Medicare beneficiaries, payers and policymakers. These include administrative price controls, coverage variation, projected shift from physician- to self-administered mAbs, and comparative effectiveness. We suggest more systematic use of “coverage with evidence development” as a means of optimally addressing these challenges. PMID:20046575

  7. Ab initio quantum chemistry: Methodology and applications

    PubMed Central

    Friesner, Richard A.

    2005-01-01

    This Perspective provides an overview of state-of-the-art ab initio quantum chemical methodology and applications. The methods that are discussed include coupled cluster theory, localized second-order Moller–Plesset perturbation theory, multireference perturbation approaches, and density functional theory. The accuracy of each approach for key chemical properties is summarized, and the computational performance is analyzed, emphasizing significant advances in algorithms and implementation over the past decade. Incorporation of a condensed-phase environment by means of mixed quantum mechanical/molecular mechanics or self-consistent reaction field techniques, is presented. A wide range of illustrative applications, focusing on materials science and biology, are discussed briefly. PMID:15870212

  8. Testing Distributed ABS System with Fault Injection

    NASA Astrophysics Data System (ADS)

    Trawczyński, Dawid; Sosnowski, Janusz; Gawkowski, Piotr

    The paper deals with the problem of adapting software implemented fault injection technique (SWIFI) to evaluate dependability of reactive microcontroller systems. We present an original methodology of disturbing controller operation and analyzing fault effects taking into account reactions of the controlled object and the impact of the system environment. Faults can be injected randomly (in space and time) or targeted at the most sensitive elements of the controller to check it at high stresses. This approach allows identifying rarely encountered problems, usually missed in classical approaches. The developed methodology has been used successfully to verify dependability of ABS system. Experimental results are commented in the paper.

  9. The occurrence of non-pulsating stars in the γ Dor and δ Sct pulsation instability regions: Results from Kepler quarter 14–17 data

    SciTech Connect

    Guzik, J. A.; Bradley, P. A.; Jackiewicz, J.; Molenda-Zakowicz, J.; Uytterhoeven, K.; Kinemuchi, K.

    2015-04-21

    In this study, the high precision long time-series photometry of the NASA Kepler spacecraft provides an excellent means to discover and characterize variability in main-sequence stars, and to make progress in interpreting the pulsations to derive stellar interior structure and test stellar models. For stars of spectral types A–F, the Kepler data revealed a number of surprises, such as more hybrid pulsating Sct and Dor pulsators than expected, pulsators lying outside of the instability regions predicted by theory, and stars that were expected to pulsate, but showed no variability. In our 2013 Astronomical Review article, we discussed the statistics of variability for 633 faint (Kepler magnitude 14–16) spectral type A–F stars observed by Kepler during Quarters 6–13 (June 2010–June 2012).

  10. The occurrence of non-pulsating stars in the γ Dor and δ Sct pulsation instability regions: Results from Kepler quarter 14–17 data

    DOE PAGESBeta

    Guzik, J. A.; Bradley, P. A.; Jackiewicz, J.; Molenda-Zakowicz, J.; Uytterhoeven, K.; Kinemuchi, K.

    2015-04-21

    In this study, the high precision long time-series photometry of the NASA Kepler spacecraft provides an excellent means to discover and characterize variability in main-sequence stars, and to make progress in interpreting the pulsations to derive stellar interior structure and test stellar models. For stars of spectral types A–F, the Kepler data revealed a number of surprises, such as more hybrid pulsating Sct and Dor pulsators than expected, pulsators lying outside of the instability regions predicted by theory, and stars that were expected to pulsate, but showed no variability. In our 2013 Astronomical Review article, we discussed the statistics ofmore » variability for 633 faint (Kepler magnitude 14–16) spectral type A–F stars observed by Kepler during Quarters 6–13 (June 2010–June 2012).« less

  11. Novel Simulated moving bed technologies

    SciTech Connect

    Purdue University

    2003-12-30

    Cellulose and hemicellulose from plants and other biomass can be hydrolyzed to produce sugars (i.e. glucose and xylose). Once these sugars are separated from other impurities, they can serve as feedstock in fermentation to produce ethanol (as fuels), lactic acid, or other valuable chemicals. The need for producing fuels and chemicals from renewable biomass has become abundantly clear over the last decade. However, the cost of producing fermentable sugars from biomass hydrolyzate using existing technology is relatively high and has been a major obstacle. The objective of this project is to develop an efficient and economical simulated moving bed (SMB) process to recover fermentable sugars from biomass hydrolyzate. Sulfuric acid can hydrolyze the cellulose and hemicellulose in biomass to sugars, but this process can generate byproducts such as acetic acid, and can lead to further degradation of the xylose to furfural and glucose to hydroxymethyl furfural (HMF). Also, lignin and other compounds in the biomass will degrade to various phenolic compounds. If the concentrations of these compounds exceed certain threshold levels, they will be toxic to the downstream fermentation, and will severely limit the usefulness of the derived sugars. Standard post-hydrolysis processing involves neutralization of sulfuric acid, usually with lime (calcium hydroxide). A study by Wooley et al.showed that the limed hydrolyzate gave a low ethanol yield in fermentation test (20% of theoretical yield compared to 77% of theoretical yield from fermentation of pure sugars). They showed that instead of adding lime, an ion exclusion chromatography process could be used to remove acids, as well as to isolate the sugars from the biomass hydrolyzate. In this project, we investigated the feasibility of developing an economical SMB process based on (1) a polymeric adsorbent, Dowex99, which was used by Wooley et al., (2) a second polymeric adsorbent, poly-4-vinyl pyridine (or PVP in short, Reilly

  12. On Your Mark, Get Set, Move!

    ERIC Educational Resources Information Center

    Minter, Sydney

    2007-01-01

    Moving a library collection is no easy feat. The librarian will need time, energy, and plenty of help to accomplish this enormous job. Although seldom easy or painless, the job can be simplified if the librarian and her staff plan carefully, prepare the collection, and organize the move. This article describes the planning, preparation and…

  13. Three "Moves" in Enactivist Research: A Reflection

    ERIC Educational Resources Information Center

    Simmt, Elaine; Kieren, Tom

    2015-01-01

    In this paper the authors reflect on the contents of this current issue of ZDM and ask why focus an entire issue on enactivism as a research methodology in mathematics education. In their synthesis of the papers they distinguish and explicate what they observe as three moves in the enactivist research discussed. The first move (and the one that…

  14. Fixing the Shadows While Moving the Gnomon

    ERIC Educational Resources Information Center

    Gangui, Alejandro

    2015-01-01

    It is a common practice to fix a vertical gnomon and study the moving shadow cast by it. This shows our local solar time and gives us a hint regarding the season in which we perform the observation. The moving shadow can also tell us our latitude with high precision. In this paper we propose to exchange the roles and while keeping the shadows…

  15. Theses "Discussion" Sections: A Structural Move Analysis

    ERIC Educational Resources Information Center

    Nodoushan, Mohammad Ali Salmani; Khakbaz, Nafiseh

    2011-01-01

    The current study aimed at finding the probable differences between the move structure of Iranian MA graduates' thesis discussion subgenres and those of their non-Iranian counterparts, on the one hand, and those of journal paper authors, on the other. It also aimed at identifying the moves that are considered obligatory, conventional, or optional…

  16. 39 CFR 777.23 - Moving expenses.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 39 Postal Service 1 2011-07-01 2011-07-01 false Moving expenses. 777.23 Section 777.23 Postal Service UNITED STATES POSTAL SERVICE SPECIAL REGULATIONS RELOCATION ASSISTANCE AND REAL PROPERTY ACQUISITION POLICIES Uniform Relocation Assistance § 777.23 Moving expenses. (a) Eligibility. (1) Residential displaced persons are entitled to...

  17. Temperature Distribution in a Uniformly Moving Medium

    ERIC Educational Resources Information Center

    Mitchell, Joseph D.; Petrov, Nikola P.

    2009-01-01

    We apply several physical ideas to determine the steady temperature distribution in a medium moving with uniform velocity between two infinite parallel plates. We compute it in the coordinate frame moving with the medium by integration over the "past" to account for the influence of an infinite set of instantaneous point sources of heat in past…

  18. Moving core beam energy absorber and converter

    DOEpatents

    Degtiarenko, Pavel V.

    2012-12-18

    A method and apparatus for the prevention of overheating of laser or particle beam impact zones through the use of a moving-in-the-coolant-flow arrangement for the energy absorbing core of the device. Moving of the core spreads the energy deposition in it in 1, 2, or 3 dimensions, thus increasing the effective cooling area of the device.

  19. Ab initio non-relativistic spin dynamics

    SciTech Connect

    Ding, Feizhi; Goings, Joshua J.; Li, Xiaosong; Frisch, Michael J.

    2014-12-07

    Many magnetic materials do not conform to the (anti-)ferromagnetic paradigm where all electronic spins are aligned to a global magnetization axis. Unfortunately, most electronic structure methods cannot describe such materials with noncollinear electron spin on account of formally requiring spin alignment. To overcome this limitation, it is necessary to generalize electronic structure methods and allow each electron spin to rotate freely. Here, we report the development of an ab initio time-dependent non-relativistic two-component spinor (TDN2C), which is a generalization of the time-dependent Hartree-Fock equations. Propagating the TDN2C equations in the time domain allows for the first-principles description of spin dynamics. A numerical tool based on the Hirshfeld partitioning scheme is developed to analyze the time-dependent spin magnetization. In this work, we also introduce the coupling between electron spin and a homogenous magnetic field into the TDN2C framework to simulate the response of the electronic spin degrees of freedom to an external magnetic field. This is illustrated for several model systems, including the spin-frustrated Li{sub 3} molecule. Exact agreement is found between numerical and analytic results for Larmor precession of hydrogen and lithium atoms. The TDN2C method paves the way for the ab initio description of molecular spin transport and spintronics in the time domain.

  20. Ab initio non-relativistic spin dynamics

    NASA Astrophysics Data System (ADS)

    Ding, Feizhi; Goings, Joshua J.; Frisch, Michael J.; Li, Xiaosong

    2014-12-01

    Many magnetic materials do not conform to the (anti-)ferromagnetic paradigm where all electronic spins are aligned to a global magnetization axis. Unfortunately, most electronic structure methods cannot describe such materials with noncollinear electron spin on account of formally requiring spin alignment. To overcome this limitation, it is necessary to generalize electronic structure methods and allow each electron spin to rotate freely. Here, we report the development of an ab initio time-dependent non-relativistic two-component spinor (TDN2C), which is a generalization of the time-dependent Hartree-Fock equations. Propagating the TDN2C equations in the time domain allows for the first-principles description of spin dynamics. A numerical tool based on the Hirshfeld partitioning scheme is developed to analyze the time-dependent spin magnetization. In this work, we also introduce the coupling between electron spin and a homogenous magnetic field into the TDN2C framework to simulate the response of the electronic spin degrees of freedom to an external magnetic field. This is illustrated for several model systems, including the spin-frustrated Li3 molecule. Exact agreement is found between numerical and analytic results for Larmor precession of hydrogen and lithium atoms. The TDN2C method paves the way for the ab initio description of molecular spin transport and spintronics in the time domain.

  1. Quantum phases of AB 2 fermionic chains

    NASA Astrophysics Data System (ADS)

    Murcia-Correa, L. S.; Franco, R.; Silva-Valencia, J.

    2016-02-01

    A fermionic chain is a one-dimensional system with fermions that interact locally and can jump between sites in the lattice, in particular an AB n chain type, where A and B are sites that exhibit a difference in energy level of Δ and site B is repeated n-times, such that the unit cell has n +1 sites. A limit case of this model, called the ionic Hubbard model (n = 1), has been widely studied due to its interesting physics and applications. In this paper, we study the ground state of an AB 2 chain, which describes the material R 4[Pt 2(P 2O5H2)4X] · nH 2 O. Specifically, we consider a filling with two electrons per unit cell, and using the density matrix renormalization group method we found that the system exhibits the band insulator and Mott correlated insulator phases, as well as an intermediate phase between them. For couplings of Δ = 2,10 and 20, we estimate the critical points that separate these phases through the structure factor and the energy gap in the sector of charge and spin, finding that the position of the critical point rises as a function of Δ.

  2. Longitudinal wheel slip during ABS braking

    NASA Astrophysics Data System (ADS)

    Hartikainen, Lassi; Petry, Frank; Westermann, Stephan

    2015-02-01

    Anti-lock braking system (ABS) braking tests with two subcompact passenger cars were performed on dry and wet asphalt, as well as on snow and ice surfaces. The operating conditions of the tyres in terms of wheel slip were evaluated using histograms of the wheel slip data. The results showed different average slip levels for different road surfaces. It was also found that changes in the tyre tread stiffness affected the slip operating range through a modification of the slip value at which the maximum longitudinal force is achieved. Variation of the tyre footprint length through modifications in the inflation pressure affected the slip operating range as well. Differences in the slip distribution between vehicles with different brake controllers were also observed. The changes in slip operating range in turn modified the relative local sliding speeds between the tyre and the road. The results highlight the importance of the ABS controller's ability to adapt to changing slip-force characteristics of tyres and provide estimates of the magnitude of the effects of different tyre and road operating conditions.

  3. Ab Initio Neutron Drops with Chiral Hamiltonians

    NASA Astrophysics Data System (ADS)

    Potter, Hugh; Maris, Pieter; Vary, James

    2015-04-01

    Ab initio calculations for neutron drops are of interest for insights into neutron-rich nuclei and neutron star matter, and for examining the neutron-only sector of nucleon-nucleon and 3-nucleon interactions. I present ab initio results calculated using the no-core shell model with 2- and 3-body chiral Hamiltonians for neutron drops up to 20 neutrons confined in a 10 MeV harmonic trap. I discuss ground state energies, internal energies, radii, and evidence for pairing. In addition, excitation energies can be used to investigate the spin-orbit splittings in the p-shell and sd -shell. Prior Green's Function Monte Carlo calculations using the Argonne v8' potential with added 3-nucleon forces serve as a comparison. Supported by DOE Grants DESC0008485 (SciDAC/NUCLEI), DE-FG02-87ER40371, and NSF Grant 0904782; computational resources provided by the Oak Ridge Leadership Computing Facility (DOE Office of Science Contract DE-AC05-00OR22725) under an INCITE award.

  4. Moving Matters: The Causal Effect of Moving Schools on Student Performance. Working Paper #01-15

    ERIC Educational Resources Information Center

    Schwartz, Amy Ellen; Stiefel, Leanna; Cordes, Sarah A.

    2015-01-01

    The majority of existing research on mobility indicates that students do worse in the year of a school move. This research, however, has been unsuccessful in isolating the causal effects of mobility and often fails to distinguish the heterogeneous impacts of moves, conflating structural moves (mandated by a school's terminal grade) and…

  5. Ab initio no core full configuration approach for light nuclei

    NASA Astrophysics Data System (ADS)

    Kim, Youngman; Shin, Ik Jae; Maris, Pieter; Vary, James P.; Forssén, Christian; Rotureau, Jimmy

    2014-07-01

    Comprehensive understanding of the structure and reactions of light nuclei poses theoretical and computational challenges. Still, a number of ab initio approaches have been developed to calculate the properties of atomic nuclei using fundamental interactions among nucleons. Among them, we work with the ab initio no core full configuration (NCFC) method and ab initio no core Gamow Shell Model (GSM). We first review these approaches and present some recent results.

  6. Ab initio no core full configuration approach for light nuclei

    NASA Astrophysics Data System (ADS)

    Kim, Youngman; Shin, Ik Jae; Maris, Pieter; Vary, James P.; Forssén, Christian; Rotureau, Jimmy

    2015-10-01

    Comprehensive understanding of the structure and reactions of light nuclei poses theoretical and computational challenges. Still, a number of ab initio approaches have been developed to calculate the properties of atomic nuclei using fundamental interactions among nucleons. Among them, we work with the ab initio no core full configuration (NCFC) method and ab initio no core Gamow Shell Model (GSM). We first review these approaches and present some recent results.

  7. Exoplanet Caught on the Move

    NASA Astrophysics Data System (ADS)

    2010-06-01

    For the first time, astronomers have been able to directly follow the motion of an exoplanet as it moves from one side of its host star to the other. The planet has the smallest orbit so far of all directly imaged exoplanets, lying almost as close to its parent star as Saturn is to the Sun. Scientists believe that it may have formed in a similar way to the giant planets in the Solar System. Because the star is so young, this discovery proves that gas giant planets can form within discs in only a few million years, a short time in cosmic terms. Only 12 million years old, or less than three-thousandths of the age of the Sun, Beta Pictoris is 75% more massive than our parent star. It is located about 60 light-years away towards the constellation of Pictor (the Painter) and is one of the best-known examples of a star surrounded by a dusty debris disc [1]. Earlier observations showed a warp of the disc, a secondary inclined disc and comets falling onto the star. "Those were indirect, but tell-tale signs that strongly suggested the presence of a massive planet, and our new observations now definitively prove this," says team leader Anne-Marie Lagrange. "Because the star is so young, our results prove that giant planets can form in discs in time-spans as short as a few million years." Recent observations have shown that discs around young stars disperse within a few million years, and that giant planet formation must occur faster than previously thought. Beta Pictoris is now clear proof that this is indeed possible. The team used the NAOS-CONICA instrument (or NACO [2]), mounted on one of the 8.2-metre Unit Telescopes of ESO's Very Large Telescope (VLT), to study the immediate surroundings of Beta Pictoris in 2003, 2008 and 2009. In 2003 a faint source inside the disc was seen (eso0842), but it was not possible to exclude the remote possibility that it was a background star. In new images taken in 2008 and spring 2009 the source had disappeared! The most recent

  8. Sediment response to moving rainstorms: laboratory experiments

    NASA Astrophysics Data System (ADS)

    de Lima, J. L. M. P.

    2009-04-01

    The soil material transported by surface runoff is an important factor, for example, in water quality management, environmental decision making, urban management and ecosystems sustainability. This study aims at contributing to increased understanding of water erosion factors and processes. The main objective is to quantify experimentally the soil loss caused by both non-moving and moving rainstorms. The importance of storm movement, due to the combined effect of wind and rain, on surface flows has long been recognised, at scales ranging from headwater scales to larger catchment basins. All these processes (rainfall, wind, runoff, soil erosion) involved are germane for investigation at different scales. In this study, laboratory experiments were carried out using several soil flumes and a movable sprinkling-type rainfall simulator. To simulate moving rainstorms, the rainfall simulator was moved upstream and downstream over the soil surface at different speeds. During runoff events overland flow and sediment transport were measured in order to determine hydrographs and sediment production over time. The size distribution of the eroded material is governed by the capacity of the flowing water to transport it. Granulometric curves obtained through conventional hand sieving and optical spectrophotometer method (material below 0.250 mm) were constructed. Distinct hydrologic responses for storms moving upstream and downstream were identified. Soil loss by sheet erosion caused by downstream moving rainstorms was higher than that caused by identical upstream moving rainfall storms or non-moving storms. The results also show that storm movement, affecting spatial and temporal distributions of rainfall, has a marked influence on the granulometric characteristics of sediments transported by overland flow during the runoff event. Storms moving downslope are the most potentially hazardous in terms of erosion.

  9. The BASS survey for brown dwarfs in young moving groups

    NASA Astrophysics Data System (ADS)

    Gagne, Jonathan; Lafreniere, David; Doyon, Rene; Malo, Lison; Faherty, Jacqueline K.; Artigau, Etienne; Cruz, Kelle L.; Burgasser, Adam J.; Filippazzo, Joe; Naud, Marie-Eve; Albert, Loic; Bouchard, Sandie; Gizis, John; Robert, Jasmin; Nadeau, Daniel; Bowsher, Emily C.; Nicholls, Christine

    2016-01-01

    I will present in this dissertation talk the construction and follow-up of the BANYAN All-Sky Survey (BASS) that we led to identify dozens of new isolated young brown dwarfs in the Solar neighborhood, several of which have physical properties such as mass, age and temperature that make them similar to exoplanets that were recently discovered using the method of direct imaging.Such isolated analogs of the giant, gaseous exoplanets are precious benchmarks that will allow a deep characterization of their atmospheres using high-resolution and high signal-to-noise spectroscopy, which is made possible due to the absence of a nearby and bright host star.I will end by describing BASS-Ultracool, an extension of BASS that focuses on the identification of extremely cool isolated exoplanet analogs that display methane in their atmospheres. This survey has already uncovered the first bonafide T dwarf member of a moving group, the ~150 Myr AB Doradus T5, SDSS1110+0116.

  10. Exoplanet Caught on the Move

    NASA Astrophysics Data System (ADS)

    2010-06-01

    For the first time, astronomers have been able to directly follow the motion of an exoplanet as it moves from one side of its host star to the other. The planet has the smallest orbit so far of all directly imaged exoplanets, lying almost as close to its parent star as Saturn is to the Sun. Scientists believe that it may have formed in a similar way to the giant planets in the Solar System. Because the star is so young, this discovery proves that gas giant planets can form within discs in only a few million years, a short time in cosmic terms. Only 12 million years old, or less than three-thousandths of the age of the Sun, Beta Pictoris is 75% more massive than our parent star. It is located about 60 light-years away towards the constellation of Pictor (the Painter) and is one of the best-known examples of a star surrounded by a dusty debris disc [1]. Earlier observations showed a warp of the disc, a secondary inclined disc and comets falling onto the star. "Those were indirect, but tell-tale signs that strongly suggested the presence of a massive planet, and our new observations now definitively prove this," says team leader Anne-Marie Lagrange. "Because the star is so young, our results prove that giant planets can form in discs in time-spans as short as a few million years." Recent observations have shown that discs around young stars disperse within a few million years, and that giant planet formation must occur faster than previously thought. Beta Pictoris is now clear proof that this is indeed possible. The team used the NAOS-CONICA instrument (or NACO [2]), mounted on one of the 8.2-metre Unit Telescopes of ESO's Very Large Telescope (VLT), to study the immediate surroundings of Beta Pictoris in 2003, 2008 and 2009. In 2003 a faint source inside the disc was seen (eso0842), but it was not possible to exclude the remote possibility that it was a background star. In new images taken in 2008 and spring 2009 the source had disappeared! The most recent

  11. Guiding ab initio calculations by alchemical derivatives.

    PubMed

    to Baben, M; Achenbach, J O; von Lilienfeld, O A

    2016-03-14

    We assess the concept of alchemical transformations for predicting how a further and not-tested change in composition would change materials properties. This might help to guide ab initio calculations through multidimensional property-composition spaces. Equilibrium volumes, bulk moduli, and relative lattice stability of fcc and bcc 4d transition metals Zr, Nb, Mo, Tc, Ru, Rh, Pd, and Ag are calculated using density functional theory. Alchemical derivatives predict qualitative trends in lattice stability while equilibrium volumes and bulk moduli are predicted with less than 9% and 28% deviation, respectively. Predicted changes in equilibrium volume and bulk moduli for binary and ternary mixtures of Rh-Pd-Ag are in qualitative agreement even for predicted bulk modulus changes as large as +100% or -50%. Based on these results, it is suggested that alchemical transformations could be meaningful for enhanced sampling in the context of virtual high-throughput materials screening projects. PMID:26979677

  12. Ab initio determination of light hadron masses.

    PubMed

    Dürr, S; Fodor, Z; Frison, J; Hoelbling, C; Hoffmann, R; Katz, S D; Krieg, S; Kurth, T; Lellouch, L; Lippert, T; Szabo, K K; Vulvert, G

    2008-11-21

    More than 99% of the mass of the visible universe is made up of protons and neutrons. Both particles are much heavier than their quark and gluon constituents, and the Standard Model of particle physics should explain this difference. We present a full ab initio calculation of the masses of protons, neutrons, and other light hadrons, using lattice quantum chromodynamics. Pion masses down to 190 mega-electron volts are used to extrapolate to the physical point, with lattice sizes of approximately four times the inverse pion mass. Three lattice spacings are used for a continuum extrapolation. Our results completely agree with experimental observations and represent a quantitative confirmation of this aspect of the Standard Model with fully controlled uncertainties. PMID:19023076

  13. Discovering chemistry with an ab initio nanoreactor

    DOE PAGESBeta

    Wang, Lee-Ping; Titov, Alexey; McGibbon, Robert; Liu, Fang; Pande, Vijay S.; Martínez, Todd J.

    2014-11-02

    Chemical understanding is driven by the experimental discovery of new compounds and reactivity, and is supported by theory and computation that provides detailed physical insight. While theoretical and computational studies have generally focused on specific processes or mechanistic hypotheses, recent methodological and computational advances harken the advent of their principal role in discovery. Here we report the development and application of the ab initio nanoreactor – a highly accelerated, first-principles molecular dynamics simulation of chemical reactions that discovers new molecules and mechanisms without preordained reaction coordinates or elementary steps. Using the nanoreactor we show new pathways for glycine synthesis frommore » primitive compounds proposed to exist on the early Earth, providing new insight into the classic Urey-Miller experiment. Ultimately, these results highlight the emergence of theoretical and computational chemistry as a tool for discovery in addition to its traditional role of interpreting experimental findings.« less

  14. Ab initio molar volumes and Gaussian radii.

    PubMed

    Parsons, Drew F; Ninham, Barry W

    2009-02-12

    Ab initio molar volumes are calculated and used to derive radii for ions and neutral molecules using a spatially diffuse model of the electron distribution with Gaussian spread. The Gaussian radii obtained can be used for computation of nonelectrostatic ion-ion dispersion forces that underlie Hofmeister specific ion effects. Equivalent hard-sphere radii are also derived, and these are in reasonable agreement with crystalline ionic radii. The Born electrostatic self-energy is derived for a Gaussian model of the electronic charge distribution. It is shown that the ionic volumes used in electrostatic calculations of strongly hydrated cosmotropic ions ought best to include the first hydration shell. Ionic volumes for weakly hydrated chaotropic metal cations should exclude electron overlap (in electrostatic calculations). Spherical radii are calculated as well as nonisotropic ellipsoidal radii for nonspherical ions, via their nonisotropic static polarizability tensors. PMID:19140766

  15. Discovering chemistry with an ab initio nanoreactor

    NASA Astrophysics Data System (ADS)

    Martinez, Todd

    Traditional approaches for modeling chemical reaction networks such as those involved in combustion have focused on identifying individual reactions and using theoretical approaches to explore the underlying mechanisms. Recent advances involving graphical processing units (GPUs), commodity products developed for the videogaming industry, have made it possible to consider a distinct approach wherein one attempts to discover chemical reactions and mechanisms. We provide a brief summary of these developments and then discuss the concept behind the ``ab initio nanoreactor'' which explores the space of possible chemical reactions and molecular species for a given stoichiometry. The nanoreactor concept is exemplified with an example to the Urey-Miller reaction network which has been previously advanced as a potential model for prebiotic chemistry. We briefly discuss some of the future directions envisioned for the development of this nanoreactor concept.

  16. Discovering chemistry with an ab initio nanoreactor

    PubMed Central

    Wang, Lee-Ping; Titov, Alexey; McGibbon, Robert; Liu, Fang; Pande, Vijay S.; Martínez, Todd J.

    2014-01-01

    Chemical understanding is driven by the experimental discovery of new compounds and reactivity, and is supported by theory and computation that provides detailed physical insight. While theoretical and computational studies have generally focused on specific processes or mechanistic hypotheses, recent methodological and computational advances harken the advent of their principal role in discovery. Here we report the development and application of the ab initio nanoreactor – a highly accelerated, first-principles molecular dynamics simulation of chemical reactions that discovers new molecules and mechanisms without preordained reaction coordinates or elementary steps. Using the nanoreactor we show new pathways for glycine synthesis from primitive compounds proposed to exist on the early Earth, providing new insight into the classic Urey-Miller experiment. These results highlight the emergence of theoretical and computational chemistry as a tool for discovery in addition to its traditional role of interpreting experimental findings. PMID:25411881

  17. Guiding ab initio calculations by alchemical derivatives

    NASA Astrophysics Data System (ADS)

    to Baben, M.; Achenbach, J. O.; von Lilienfeld, O. A.

    2016-03-01

    We assess the concept of alchemical transformations for predicting how a further and not-tested change in composition would change materials properties. This might help to guide ab initio calculations through multidimensional property-composition spaces. Equilibrium volumes, bulk moduli, and relative lattice stability of fcc and bcc 4d transition metals Zr, Nb, Mo, Tc, Ru, Rh, Pd, and Ag are calculated using density functional theory. Alchemical derivatives predict qualitative trends in lattice stability while equilibrium volumes and bulk moduli are predicted with less than 9% and 28% deviation, respectively. Predicted changes in equilibrium volume and bulk moduli for binary and ternary mixtures of Rh-Pd-Ag are in qualitative agreement even for predicted bulk modulus changes as large as +100% or -50%. Based on these results, it is suggested that alchemical transformations could be meaningful for enhanced sampling in the context of virtual high-throughput materials screening projects.

  18. Discovering chemistry with an ab initio nanoreactor.

    PubMed

    Wang, Lee-Ping; Titov, Alexey; McGibbon, Robert; Liu, Fang; Pande, Vijay S; Martínez, Todd J

    2014-12-01

    Chemical understanding is driven by the experimental discovery of new compounds and reactivity, and is supported by theory and computation that provide detailed physical insight. Although theoretical and computational studies have generally focused on specific processes or mechanistic hypotheses, recent methodological and computational advances harken the advent of their principal role in discovery. Here we report the development and application of the ab initio nanoreactor--a highly accelerated first-principles molecular dynamics simulation of chemical reactions that discovers new molecules and mechanisms without preordained reaction coordinates or elementary steps. Using the nanoreactor, we show new pathways for glycine synthesis from primitive compounds proposed to exist on the early Earth, which provide new insight into the classic Urey-Miller experiment. These results highlight the emergence of theoretical and computational chemistry as a tool for discovery, in addition to its traditional role of interpreting experimental findings. PMID:25411881

  19. Discovering chemistry with an ab initio nanoreactor

    NASA Astrophysics Data System (ADS)

    Wang, Lee-Ping; Titov, Alexey; McGibbon, Robert; Liu, Fang; Pande, Vijay S.; Martínez, Todd J.

    2014-12-01

    Chemical understanding is driven by the experimental discovery of new compounds and reactivity, and is supported by theory and computation that provide detailed physical insight. Although theoretical and computational studies have generally focused on specific processes or mechanistic hypotheses, recent methodological and computational advances harken the advent of their principal role in discovery. Here we report the development and application of the ab initio nanoreactor—a highly accelerated first-principles molecular dynamics simulation of chemical reactions that discovers new molecules and mechanisms without preordained reaction coordinates or elementary steps. Using the nanoreactor, we show new pathways for glycine synthesis from primitive compounds proposed to exist on the early Earth, which provide new insight into the classic Urey-Miller experiment. These results highlight the emergence of theoretical and computational chemistry as a tool for discovery, in addition to its traditional role of interpreting experimental findings.

  20. Ab Initio Modeling of Molecular Radiation

    NASA Technical Reports Server (NTRS)

    Jaffe, Richard; Schwenke, David

    2014-01-01

    Radiative emission from excited states of atoms and molecules can comprise a significant fraction of the total heat flux experienced by spacecraft during atmospheric entry at hypersonic speeds. For spacecraft with ablating heat shields, some of this radiative flux can be absorbed by molecular constituents in the boundary layer that are formed by the ablation process. Ab initio quantum mechanical calculations are carried out to predict the strengths of these emission and absorption processes. This talk will describe the methods used in these calculations using, as examples, the 4th positive emission bands of CO and the 1g+ 1u+ absorption in C3. The results of these calculations are being used as input to NASA radiation modeling codes like NeqAir, HARA and HyperRad.

  1. Discovering chemistry with an ab initio nanoreactor

    SciTech Connect

    Wang, Lee-Ping; Titov, Alexey; McGibbon, Robert; Liu, Fang; Pande, Vijay S.; Martínez, Todd J.

    2014-11-02

    Chemical understanding is driven by the experimental discovery of new compounds and reactivity, and is supported by theory and computation that provides detailed physical insight. While theoretical and computational studies have generally focused on specific processes or mechanistic hypotheses, recent methodological and computational advances harken the advent of their principal role in discovery. Here we report the development and application of the ab initio nanoreactor – a highly accelerated, first-principles molecular dynamics simulation of chemical reactions that discovers new molecules and mechanisms without preordained reaction coordinates or elementary steps. Using the nanoreactor we show new pathways for glycine synthesis from primitive compounds proposed to exist on the early Earth, providing new insight into the classic Urey-Miller experiment. Ultimately, these results highlight the emergence of theoretical and computational chemistry as a tool for discovery in addition to its traditional role of interpreting experimental findings.

  2. Ab Initio Calculation of the Hoyle State

    SciTech Connect

    Epelbaum, Evgeny; Krebs, Hermann; Lee, Dean; Meissner, Ulf-G.

    2011-05-13

    The Hoyle state plays a crucial role in the helium burning of stars heavier than our Sun and in the production of carbon and other elements necessary for life. This excited state of the carbon-12 nucleus was postulated by Hoyle as a necessary ingredient for the fusion of three alpha particles to produce carbon at stellar temperatures. Although the Hoyle state was seen experimentally more than a half century ago nuclear theorists have not yet uncovered the nature of this state from first principles. In this Letter we report the first ab initio calculation of the low-lying states of carbon-12 using supercomputer lattice simulations and a theoretical framework known as effective field theory. In addition to the ground state and excited spin-2 state, we find a resonance at -85(3) MeV with all of the properties of the Hoyle state and in agreement with the experimentally observed energy.

  3. Ab initio alpha-alpha scattering

    NASA Astrophysics Data System (ADS)

    Elhatisari, Serdar; Lee, Dean; Rupak, Gautam; Epelbaum, Evgeny; Krebs, Hermann; Lähde, Timo A.; Luu, Thomas; Meißner, Ulf-G.

    2015-12-01

    Processes such as the scattering of alpha particles (4He), the triple-alpha reaction, and alpha capture play a major role in stellar nucleosynthesis. In particular, alpha capture on carbon determines the ratio of carbon to oxygen during helium burning, and affects subsequent carbon, neon, oxygen, and silicon burning stages. It also substantially affects models of thermonuclear type Ia supernovae, owing to carbon detonation in accreting carbon-oxygen white-dwarf stars. In these reactions, the accurate calculation of the elastic scattering of alpha particles and alpha-like nuclei—nuclei with even and equal numbers of protons and neutrons—is important for understanding background and resonant scattering contributions. First-principles calculations of processes involving alpha particles and alpha-like nuclei have so far been impractical, owing to the exponential growth of the number of computational operations with the number of particles. Here we describe an ab initio calculation of alpha-alpha scattering that uses lattice Monte Carlo simulations. We use lattice effective field theory to describe the low-energy interactions of protons and neutrons, and apply a technique called the ‘adiabatic projection method’ to reduce the eight-body system to a two-cluster system. We take advantage of the computational efficiency and the more favourable scaling with system size of auxiliary-field Monte Carlo simulations to compute an ab initio effective Hamiltonian for the two clusters. We find promising agreement between lattice results and experimental phase shifts for s-wave and d-wave scattering. The approximately quadratic scaling of computational operations with particle number suggests that it should be possible to compute alpha scattering and capture on carbon and oxygen in the near future. The methods described here can be applied to ultracold atomic few-body systems as well as to hadronic systems using lattice quantum chromodynamics to describe the interactions of

  4. Ab initio alpha-alpha scattering.

    PubMed

    Elhatisari, Serdar; Lee, Dean; Rupak, Gautam; Epelbaum, Evgeny; Krebs, Hermann; Lähde, Timo A; Luu, Thomas; Meißner, Ulf-G

    2015-12-01

    Processes such as the scattering of alpha particles ((4)He), the triple-alpha reaction, and alpha capture play a major role in stellar nucleosynthesis. In particular, alpha capture on carbon determines the ratio of carbon to oxygen during helium burning, and affects subsequent carbon, neon, oxygen, and silicon burning stages. It also substantially affects models of thermonuclear type Ia supernovae, owing to carbon detonation in accreting carbon-oxygen white-dwarf stars. In these reactions, the accurate calculation of the elastic scattering of alpha particles and alpha-like nuclei--nuclei with even and equal numbers of protons and neutrons--is important for understanding background and resonant scattering contributions. First-principles calculations of processes involving alpha particles and alpha-like nuclei have so far been impractical, owing to the exponential growth of the number of computational operations with the number of particles. Here we describe an ab initio calculation of alpha-alpha scattering that uses lattice Monte Carlo simulations. We use lattice effective field theory to describe the low-energy interactions of protons and neutrons, and apply a technique called the 'adiabatic projection method' to reduce the eight-body system to a two-cluster system. We take advantage of the computational efficiency and the more favourable scaling with system size of auxiliary-field Monte Carlo simulations to compute an ab initio effective Hamiltonian for the two clusters. We find promising agreement between lattice results and experimental phase shifts for s-wave and d-wave scattering. The approximately quadratic scaling of computational operations with particle number suggests that it should be possible to compute alpha scattering and capture on carbon and oxygen in the near future. The methods described here can be applied to ultracold atomic few-body systems as well as to hadronic systems using lattice quantum chromodynamics to describe the interactions of

  5. Ablation dynamics in laser sclerotomy ab externo

    NASA Astrophysics Data System (ADS)

    Brinkmann, Ralf; Droege, Gerit; Mohrenstecher, Dirk; Scheu, M.; Birngruber, Reginald

    1996-01-01

    Laser sclerostomy ab externo with flashlamp excited mid-IR laser systems emitting in the 2-3 micrometer spectral range is in phase II clinical trials. Although acutely high success rates were achieved, the restenosis rate after several months is about 40%. Laser pulses of several hundreds of microseconds, known to induce thermo-mechanical explosive evaporation were used for this procedure. We investigated the ablation dynamics in tissue and the cavitation bubble dynamics in water by means of an Er:YAG laser system to estimate the extent of mechanical damage zones in the sclera and in the anterior chamber, which may contribute to the clinical failure. We found substantial mechanical tissue deformation during the ablation process caused by the cavitation effects. Stress waves up to several bar generated by explosive evaporization were measured. The fast mechanical stretching and collapsing of the scleral tissue induced by cavitation resulted in tissue dissection as could be proved by flash photography and histology. The observed high restenosis might be a result of a subsequent enhanced wound healing process. Early fistula occlusions due to iris adherences, observed in about 20% of the clinical cases may be attributed to intraocular trauma induced by vapor bubble expansion through the anterior chamber after scleral perforation. An automatic feedback system minimizing adverse effects by steering and terminating the laser process during scleral fistulization is demonstrated. Moreover, a new approach in laser sclerostomy ab externo is presented using a cw-IR laser diode system emitting at the 1.94 micrometer mid-IR water absorption peak. This system was used in vitro and showed smaller damage zones compared to the pulsed laser radiation.

  6. 39 CFR 777.23 - Moving expenses.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... payment is limited to the pro rata value for the remaining useful life of any existing license, permit, or..., fees and permits when not paid as part of the moving expenses. (viii) Feasibility surveys, soil...

  7. 39 CFR 777.23 - Moving expenses.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... payment is limited to the pro rata value for the remaining useful life of any existing license, permit, or..., fees and permits when not paid as part of the moving expenses. (viii) Feasibility surveys, soil...

  8. 39 CFR 777.23 - Moving expenses.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... payment is limited to the pro rata value for the remaining useful life of any existing license, permit, or..., fees and permits when not paid as part of the moving expenses. (viii) Feasibility surveys, soil...

  9. Expedition 30 Soyuz Moves to Launch Pad

    NASA Video Gallery

    On Dec. 19, the Soyuz TMA-03M spacecraft and its booster were moved to the launch pad at the Baikonur Cosmodrome in Kazakhstan for final preparations before launch to the International Space Statio...

  10. Entropic destruction of a moving heavy quarkonium

    NASA Astrophysics Data System (ADS)

    Fadafan, Kazem Bitaghsir; Tabatabaei, Seyed Kamal

    2016-07-01

    Recently it has been shown that the peak of the quarkonium entropy at the deconfinement transition is related to the emergent entropic force which destructs the quarkonium. Using the AdS/CFT correspondence, we consider dissociation of a moving heavy quarkonium by entropic force. For larger distance of quark and antiquark, the entropy of moving quarkonium increases, monotonically. We find that the entropic force destructs the moving quarkonium easier than the static case. By considering the Maxwell charge, we study the effect of the medium on the destruction of heavy quarkonium. It is shown that the quarkonium dissociates easier in the medium. Our results imply that the quarkonium dissociates easier when it moves orthogonal to the plasma wind rather than parallel.

  11. Being moved: linguistic representation and conceptual structure

    PubMed Central

    Kuehnast, Milena; Wagner, Valentin; Wassiliwizky, Eugen; Jacobsen, Thomas; Menninghaus, Winfried

    2014-01-01

    This study explored the organization of the semantic field and the conceptual structure of moving experiences by investigating German-language expressions referring to the emotional state of being moved. We used present and past participles of eight psychological verbs as primes in a free word-association task, as these grammatical forms place their conceptual focus on the eliciting situation and on the felt emotional state, respectively. By applying a taxonomy of basic knowledge types and computing the Cognitive Salience Index, we identified joy and sadness as key emotional ingredients of being moved, and significant life events and art experiences as main elicitors of this emotional state. Metric multidimensional scaling analyses of the semantic field revealed that the core terms designate a cluster of emotional states characterized by low degrees of arousal and slightly positive valence, the latter due to a nearly balanced representation of positive and negative elements in the conceptual structure of being moved. PMID:25404924

  12. Universal transloader moves delicate equipment without stress

    NASA Technical Reports Server (NTRS)

    Barbour, J. R.; Kessler, P. N.

    1966-01-01

    Transloader moves delicate or heavy items over irregular surfaces without transmitting stress to the load. The loader is supported on three pivot points which produce a wrap free base. The base is supported by an artificial four-wheel frame.

  13. Acoustics of a Nonhomogeneous Moving Medium.

    NASA Technical Reports Server (NTRS)

    Blokhintsev, D I

    1956-01-01

    Theoretical basis of the acoustics of a moving nonhomogeneous medium is considered in this report. Experiments that illustrate or confirm some of the theoretical explanation or derivation of these acoustics are also included.

  14. Monkeys Move Robotic Wheelchairs with Their Thoughts

    MedlinePlus

    ... gov/medlineplus/news/fullstory_157593.html Monkeys Move Robotic Wheelchairs With Their Thoughts Scientists say technology might ... made it possible for monkeys to operate a robotic wheelchair using only the monkey's thoughts say the ...

  15. Tropical Storm Debby Moves into Atlantic

    NASA Video Gallery

    An animation of satellite observations shows the progression of Tropical Storm Debby from June 25-27, 2012. The animation shows that Tropical Storm Debby's center move from the northeastern Gulf of...

  16. Anomalous energetics and dynamics of moving vortices

    NASA Astrophysics Data System (ADS)

    Radzihovsky, Leo

    Motivated by the general problem of moving topological defects in an otherwise ordered state and specifically, by the anomalous dynamics observed in vortex-antivortex annihilation and coarsening experiments in freely-suspended smectic-C films, I study the deformation, energetics and dynamics of moving vortices in an overdamped xy-model and show that their properties are significantly and qualitatively modified by the motion. Supported by NSF through DMR-1001240, MRSEC DMR-0820579, and by Simons Investigator award from Simons Foundation.

  17. Anomalous Energetics and Dynamics of Moving Vortices

    NASA Astrophysics Data System (ADS)

    Radzihovsky, Leo

    2015-12-01

    Motivated by the general problem of moving topological defects in an otherwise ordered state and specifically, by the anomalous dynamics observed in vortex-antivortex annihilation and coarsening experiments in freely suspended smectic-C films, I study the deformation, energetics, and dynamics of moving vortices in an overdamped X Y model and show that their properties are significantly and qualitatively modified by the motion.

  18. Anomalous Energetics and Dynamics of Moving Vortices.

    PubMed

    Radzihovsky, Leo

    2015-12-11

    Motivated by the general problem of moving topological defects in an otherwise ordered state and specifically, by the anomalous dynamics observed in vortex-antivortex annihilation and coarsening experiments in freely suspended smectic-C films, I study the deformation, energetics, and dynamics of moving vortices in an overdamped XY model and show that their properties are significantly and qualitatively modified by the motion. PMID:26705656

  19. Near-infrared integral-field spectra of the planet/brown dwarf companion AB Pictoris b

    NASA Astrophysics Data System (ADS)

    Bonnefoy, M.; Chauvin, G.; Rojo, P.; Allard, F.; Lagrange, A.-M.; Homeier, D.; Dumas, C.; Beuzit, J.-L.

    2010-03-01

    Context. We have already imaged a co-moving companion at a projected separation of ~260 AU from the young star AB Pic A. Evolutionary model predictions based on JHK photometry of AB Pic b suggest a mass of ~13-14 MJup, placing the object at the deuterium-burning boundary. Aims: We aim to determine the spectral type, the surface gravity, and the effective temperature of AB Pic b. From the comparison of our absolute photometry to surface fluxes generated by atmospheric models, we also aim at deriving mass and radius estimates that are independent of evolutionary model predictions to test and refine them. Methods: We used the adaptive-optics-fed integral field spectrograph SINFONI to obtain high-quality, medium-resolution spectra of AB Pic b (R_λ = 1500-2000) over the 1.1-2.5 μm range. Our analysis relie on comparing our spectra to young standard templates and to the latest libraries of synthetic spectra developed by the Lyon group. Results: AB Pic b is confirmed as a young early-L dwarf companion. We derive a spectral type L0-L1 and find several features indicative of an intermediate gravity atmosphere. A comparison to synthetic spectra yields Teff = 2000+100-300 K and log(g) = 4 ± 0.5 dex. Determination of the derived atmospheric parameters of AB Pic b is limited by an imperfect match of current atmosphere spectra with our near-infrared observations of AB Pic b. The current treatment of dust settling and the missing molecular opacity lines in the atmosphere models could be responsible. By combining the observed photometry, the surface fluxes from atmosphere models and the known distance of the system, we derive new mass, luminosity, and radius estimates of AB Pic b. They independently confirm the evolutionary model predictions. We finally review the current methods used for characterizing planetary mass companions and discuss them in the perspective of future planet deep-imaging surveys that will be faced with the same limitations. Based on service

  20. Towards a Psychological Construct of Being Moved

    PubMed Central

    Menninghaus, Winfried; Wagner, Valentin; Hanich, Julian; Wassiliwizky, Eugen; Kuehnast, Milena; Jacobsen, Thomas

    2015-01-01

    The emotional state of being moved, though frequently referred to in both classical rhetoric and current language use, is far from established as a well-defined psychological construct. In a series of three studies, we investigated eliciting scenarios, emotional ingredients, appraisal patterns, feeling qualities, and the affective signature of being moved and related emotional states. The great majority of the eliciting scenarios can be assigned to significant relationship and critical life events (especially death, birth, marriage, separation, and reunion). Sadness and joy turned out to be the two preeminent emotions involved in episodes of being moved. Both the sad and the joyful variants of being moved showed a coactivation of positive and negative affect and can thus be ranked among the mixed emotions. Moreover, being moved, while featuring only low-to-mid arousal levels, was experienced as an emotional state of high intensity; this applied to responses to fictional artworks no less than to own-life and other real, but media-represented, events. The most distinctive findings regarding cognitive appraisal dimensions were very low ratings for causation of the event by oneself and for having the power to change its outcome, along with very high ratings for appraisals of compatibility with social norms and self-ideals. Putting together the characteristics identified and discussed throughout the three studies, the paper ends with a sketch of a psychological construct of being moved. PMID:26042816

  1. 12 CFR Appendixes A-B to Part 334 - [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 4 2010-01-01 2010-01-01 false A Appendixes A-B to Part 334 Banks and Banking FEDERAL DEPOSIT INSURANCE CORPORATION REGULATIONS AND STATEMENTS OF GENERAL POLICY FAIR CREDIT REPORTING Appendixes A-B to Part 334...

  2. AB1402: Design-Build Project Guidelines. 2002 Edition.

    ERIC Educational Resources Information Center

    California State Dept. of Education, Sacramento. Div. of School Facilities Planning.

    Assembly Bill (AB) 1402 authorized California's school districts to enter into design-build contracts for projects with design and construction costs exceeding $10 million. These guidelines are intended to accomplish the following purposes: (1) inform school districts of the design-build process under AB 1402; (2) help school districts to…

  3. 10 CFR Appendices A-B to Subpart F... - [Reserved

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 3 2014-01-01 2014-01-01 false A Appendices A-B to Subpart F of Part 430 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CONSERVATION PROGRAM FOR CONSUMER PRODUCTS Reserved Appendices A-B to Subpart F of Part...

  4. 10 CFR Appendices A-B to Subpart F... - [Reserved

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 3 2012-01-01 2012-01-01 false A Appendices A-B to Subpart F of Part 430 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CONSERVATION PROGRAM FOR CONSUMER PRODUCTS Reserved Appendices A-B to Subpart F of Part 430...

  5. 10 CFR Appendices A-B to Subpart F... - [Reserved

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 3 2013-01-01 2013-01-01 false A Appendices A-B to Subpart F of Part 430 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CONSERVATION PROGRAM FOR CONSUMER PRODUCTS Reserved Appendices A-B to Subpart F of Part 430...

  6. Towards Accurate Ab Initio Predictions of the Spectrum of Methane

    NASA Technical Reports Server (NTRS)

    Schwenke, David W.; Kwak, Dochan (Technical Monitor)

    2001-01-01

    We have carried out extensive ab initio calculations of the electronic structure of methane, and these results are used to compute vibrational energy levels. We include basis set extrapolations, core-valence correlation, relativistic effects, and Born- Oppenheimer breakdown terms in our calculations. Our ab initio predictions of the lowest lying levels are superb.

  7. History of California's AB 1725 and Its Major Provisions.

    ERIC Educational Resources Information Center

    Livingston, Tab

    This paper addresses the history of California's Assembly Bill 1725 (AB 1725) legislation and describes its major provisions. Signed in 1988 by Governor George Deukmejian, AB 1725's focus is to emphasize the new role of California community colleges as postsecondary institutions committed to transferring students, offering remedial courses, and…

  8. 7 CFR Exhibits A-B to Subpart G... - [Reserved

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 12 2013-01-01 2013-01-01 false A Exhibits A-B to Subpart G to Part 1822 Agriculture Regulations of the Department of Agriculture (Continued) RURAL HOUSING SERVICE, RURAL BUSINESS-COOPERATIVE..., Procedures, and Authorizations Exhibits A-B to Subpart G to Part 1822...

  9. A comparison of moving object detection methods for real-time moving object detection

    NASA Astrophysics Data System (ADS)

    Roshan, Aditya; Zhang, Yun

    2014-06-01

    Moving object detection has a wide variety of applications from traffic monitoring, site monitoring, automatic theft identification, face detection to military surveillance. Many methods have been developed across the globe for moving object detection, but it is very difficult to find one which can work globally in all situations and with different types of videos. The purpose of this paper is to evaluate existing moving object detection methods which can be implemented in software on a desktop or laptop, for real time object detection. There are several moving object detection methods noted in the literature, but few of them are suitable for real time moving object detection. Most of the methods which provide for real time movement are further limited by the number of objects and the scene complexity. This paper evaluates the four most commonly used moving object detection methods as background subtraction technique, Gaussian mixture model, wavelet based and optical flow based methods. The work is based on evaluation of these four moving object detection methods using two (2) different sets of cameras and two (2) different scenes. The moving object detection methods have been implemented using MatLab and results are compared based on completeness of detected objects, noise, light change sensitivity, processing time etc. After comparison, it is observed that optical flow based method took least processing time and successfully detected boundary of moving objects which also implies that it can be implemented for real-time moving object detection.

  10. Undoing Gender through Legislation and Schooling: The Case of AB 537 and AB 394 in California, USA

    ERIC Educational Resources Information Center

    Knotts, Greg

    2009-01-01

    This article investigates California laws AB 537: The Student Safety and Violence Prevention Act of 2000, and the recently enacted AB 394: Safe Place to Learn Act. Both demand that gender identity and sexual orientation be added to the lexicon of anti-harassment protection in public education. However, despite these progressive measures, schools…

  11. Effects of Cry1F and Cry34Ab1/35Ab1 on storage pests

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two crystalline protoxins from Bacillus thuringiensis (Bt), Cry1Fa1 and Cry34Ab1/Cry35Ab1 (Cry1F, Cry34/35), were evaluated for efficacy against lepidopteran and coleopteran storage pests. Cry1F was tested against the lepidopterans Sitotroga cerealella (Angoumois grain moth) and colonies of the lep...

  12. Nonuniform Video Size Reduction for Moving Objects

    PubMed Central

    2014-01-01

    Moving objects of interest (MOOIs) in surveillance videos are detected and encapsulated by bounding boxes. Since moving objects are defined by temporal activities through the consecutive video frames, it is necessary to examine a group of frames (GoF) to detect the moving objects. To do that, the traces of moving objects in the GoF are quantified by forming a spatiotemporal gradient map (STGM) through the GoF. Each pixel value in the STGM corresponds to the maximum temporal gradient of the spatial gradients at the same pixel location for all frames in the GoF. Therefore, the STGM highlights boundaries of the MOOI in the GoF and the optimal bounding box encapsulating the MOOI can be determined as the local areas with the peak average STGM energy. Once an MOOI and its bounding box are identified, the inside and outside of it can be treated differently for object-aware size reduction. Our optimal encapsulation method for the MOOI in the surveillance videos makes it possible to recognize the moving objects even after the low bitrate video compressions. PMID:25258738

  13. ELECTROMAGNETIC APPARATUS FOR MOVING A ROD

    DOEpatents

    Young, J.N.

    1957-08-20

    An electromagnetic device for moving an object in a linear path by increments is described. The device is specifically adapted for moving a neutron absorbing control rod into and out of the core of a reactor and consists essentially of an extension member made of magnetic material connected to one end of the control rod and mechanically flexible to grip the walls of a sleeve member when flexed, a magnetic sleeve member coaxial with and slidable between limit stops along the flexible extension, electromagnetic coils substantially centrally located with respect to the flexible extension to flex the extension member into gripping engagement with the sleeve member when ener gized, moving electromagnets at each end of the sleeve to attract the sleeve when energized, and a second gripping electromagnet positioned along the flexible extension at a distance from the previously mentioned electromagnets for gripping the extension member when energized. In use, the second gripping electromagnet is deenergized, the first gripping electromagnet is energized to fix the extension member in the sleeve, and one of the moving electromagnets is energized to attract the sleeve member toward it, thereby moving the control rod.

  14. Moving Obstacle Avoidance for Unmanned Aerial Vehicles

    NASA Astrophysics Data System (ADS)

    Lin, Yucong

    There has been a vast increase in applications of Unmanned Aerial Vehicles (UAVs) in civilian domains. To operate in the civilian airspace, a UAV must be able to sense and avoid both static and moving obstacles for flight safety. While indoor and low-altitude environments are mainly occupied by static obstacles, risks in space of higher altitude primarily come from moving obstacles such as other aircraft or flying vehicles in the airspace. Therefore, the ability to avoid moving obstacles becomes a necessity for Unmanned Aerial Vehicles. Towards enabling a UAV to autonomously sense and avoid moving obstacles, this thesis makes the following contributions. Initially, an image-based reactive motion planner is developed for a quadrotor to avoid a fast approaching obstacle. Furthermore, A Dubin's curve based geometry method is developed as a global path planner for a fixed-wing UAV to avoid collisions with aircraft. The image-based method is unable to produce an optimal path and the geometry method uses a simplified UAV model. To compensate these two disadvantages, a series of algorithms built upon the Closed-Loop Rapid Exploratory Random Tree are developed as global path planners to generate collision avoidance paths in real time. The algorithms are validated in Software-In-the-Loop (SITL) and Hardware-In-the-Loop (HIL) simulations using a fixed-wing UAV model and in real flight experiments using quadrotors. It is observed that the algorithm enables a UAV to avoid moving obstacles approaching to it with different directions and speeds.

  15. Maxwell Equations for Slow-Moving Media

    NASA Astrophysics Data System (ADS)

    Rozov, Andrey

    2015-12-01

    In the present work, the Minkowski equations obtained on the basis of theory of relativity are used to describe electromagnetic fields in moving media. But important electromagnetic processes run under non-relativistic conditions of slow-moving media. Therefore, one should carry out its description in terms of classical mechanics. Hertz derived electrodynamic equations for moving media within the frame of classical mechanics on the basis of the Maxwell theory. His equations disagree with the experimental data concerned with the moving dielectrics. In the paper, a way of description of electromagnetic fields in slow-moving media on the basis of the Maxwell theory within the frame of classical mechanics is offered by combining the Hertz approach and the experimental data concerned with the movement of dielectrics in electromagnetic fields. Received Maxwell equations lack asymmetry in the description of the reciprocal electrodynamic action of a magnet and a conductor and conform to known experimental data. Comparative analysis of the Minkowski and Maxwell models is carried out.

  16. Structural and biophysical characterization of Bacillus thuringiensis insecticidal proteins Cry34Ab1 and Cry35Ab1.

    PubMed

    Kelker, Matthew S; Berry, Colin; Evans, Steven L; Pai, Reetal; McCaskill, David G; Wang, Nick X; Russell, Joshua C; Baker, Matthew D; Yang, Cheng; Pflugrath, J W; Wade, Matthew; Wess, Tim J; Narva, Kenneth E

    2014-01-01

    Bacillus thuringiensis strains are well known for the production of insecticidal proteins upon sporulation and these proteins are deposited in parasporal crystalline inclusions. The majority of these insect-specific toxins exhibit three domains in the mature toxin sequence. However, other Cry toxins are structurally and evolutionarily unrelated to this three-domain family and little is known of their three dimensional structures, limiting our understanding of their mechanisms of action and our ability to engineer the proteins to enhance their function. Among the non-three domain Cry toxins, the Cry34Ab1 and Cry35Ab1 proteins from B. thuringiensis strain PS149B1 are required to act together to produce toxicity to the western corn rootworm (WCR) Diabrotica virgifera virgifera Le Conte via a pore forming mechanism of action. Cry34Ab1 is a protein of ∼14 kDa with features of the aegerolysin family (Pfam06355) of proteins that have known membrane disrupting activity, while Cry35Ab1 is a ∼44 kDa member of the toxin_10 family (Pfam05431) that includes other insecticidal proteins such as the binary toxin BinA/BinB. The Cry34Ab1/Cry35Ab1 proteins represent an important seed trait technology having been developed as insect resistance traits in commercialized corn hybrids for control of WCR. The structures of Cry34Ab1 and Cry35Ab1 have been elucidated to 2.15 Å and 1.80 Å resolution, respectively. The solution structures of the toxins were further studied by small angle X-ray scattering and native electrospray ion mobility mass spectrometry. We present here the first published structure from the aegerolysin protein domain family and the structural comparisons of Cry34Ab1 and Cry35Ab1 with other pore forming toxins. PMID:25390338

  17. Structural and Biophysical Characterization of Bacillus thuringiensis Insecticidal Proteins Cry34Ab1 and Cry35Ab1

    PubMed Central

    Kelker, Matthew S.; Berry, Colin; Evans, Steven L.; Pai, Reetal; McCaskill, David G.; Wang, Nick X.; Russell, Joshua C.; Baker, Matthew D.; Yang, Cheng; Pflugrath, J. W.; Wade, Matthew; Wess, Tim J.; Narva, Kenneth E.

    2014-01-01

    Bacillus thuringiensis strains are well known for the production of insecticidal proteins upon sporulation and these proteins are deposited in parasporal crystalline inclusions. The majority of these insect-specific toxins exhibit three domains in the mature toxin sequence. However, other Cry toxins are structurally and evolutionarily unrelated to this three-domain family and little is known of their three dimensional structures, limiting our understanding of their mechanisms of action and our ability to engineer the proteins to enhance their function. Among the non-three domain Cry toxins, the Cry34Ab1 and Cry35Ab1 proteins from B. thuringiensis strain PS149B1 are required to act together to produce toxicity to the western corn rootworm (WCR) Diabrotica virgifera virgifera Le Conte via a pore forming mechanism of action. Cry34Ab1 is a protein of ∼14 kDa with features of the aegerolysin family (Pfam06355) of proteins that have known membrane disrupting activity, while Cry35Ab1 is a ∼44 kDa member of the toxin_10 family (Pfam05431) that includes other insecticidal proteins such as the binary toxin BinA/BinB. The Cry34Ab1/Cry35Ab1 proteins represent an important seed trait technology having been developed as insect resistance traits in commercialized corn hybrids for control of WCR. The structures of Cry34Ab1 and Cry35Ab1 have been elucidated to 2.15 Å and 1.80 Å resolution, respectively. The solution structures of the toxins were further studied by small angle X-ray scattering and native electrospray ion mobility mass spectrometry. We present here the first published structure from the aegerolysin protein domain family and the structural comparisons of Cry34Ab1 and Cry35Ab1 with other pore forming toxins. PMID:25390338

  18. ABS_PDv14.0 beta

    2008-07-30

    ABS_PD stands for Adaptive Background Suppression and Peak Detection algorithm. This algorithm uses an iterative process to simultaneously estimate the background and identify peaks in signals where the bakground is slowly varying relative to the peaks to be detected. This is sone on an automated manner. The algorithm can be applied to many physical processes where the desired signal is superimposed on a background. The main advantage of this algorithm is that the background canmore » be variable and doesn't have to be known. All that is required is that a set of basis function,s capa ble of representing the background, needs to be defined. Depending on the signals to be processed, the basis functions can be as simple as low order polynomials. The current algorithm has polynomials built-in and allows for additional basis functions to be defined by the user. An additional advantage is that the algorithm does not use any derivatives in detection of peaks and thus allows for analysis of noisy data. The noise level in the data is automatically taken into account when setting thresholds for peak detection.« less

  19. Phonocatalysis. An ab initio simulation experiment

    NASA Astrophysics Data System (ADS)

    Kim, Kwangnam; Kaviany, Massoud

    2016-06-01

    Using simulations, we postulate and show that heterocatalysis on large-bandgap semiconductors can be controlled by substrate phonons, i.e., phonocatalysis. With ab initio calculations, including molecular dynamic simulations, the chemisorbed dissociation of XeF6 on h-BN surface leads to formation of XeF4 and two surface F/h-BN bonds. The reaction pathway and energies are evaluated, and the sorption and reaction emitted/absorbed phonons are identified through spectral analysis of the surface atomic motion. Due to large bandgap, the atomic vibration (phonon) energy transfer channels dominate and among them is the match between the F/h-BN covalent bond stretching and the optical phonons. We show that the chemisorbed dissociation (the pathway activation ascent) requires absorption of large-energy optical phonons. Then using progressively heavier isotopes of B and N atoms, we show that limiting these high-energy optical phonons inhibits the chemisorbed dissociation, i.e., controllable phonocatalysis.

  20. Ab initio two-component Ehrenfest dynamics

    NASA Astrophysics Data System (ADS)

    Ding, Feizhi; Goings, Joshua J.; Liu, Hongbin; Lingerfelt, David B.; Li, Xiaosong

    2015-09-01

    We present an ab initio two-component Ehrenfest-based mixed quantum/classical molecular dynamics method to describe the effect of nuclear motion on the electron spin dynamics (and vice versa) in molecular systems. The two-component time-dependent non-collinear density functional theory is used for the propagation of spin-polarized electrons while the nuclei are treated classically. We use a three-time-step algorithm for the numerical integration of the coupled equations of motion, namely, the velocity Verlet for nuclear motion, the nuclear-position-dependent midpoint Fock update, and the modified midpoint and unitary transformation method for electronic propagation. As a test case, the method is applied to the dissociation of H2 and O2. In contrast to conventional Ehrenfest dynamics, this two-component approach provides a first principles description of the dynamics of non-collinear (e.g., spin-frustrated) magnetic materials, as well as the proper description of spin-state crossover, spin-rotation, and spin-flip dynamics by relaxing the constraint on spin configuration. This method also holds potential for applications to spin transport in molecular or even nanoscale magnetic devices.

  1. Ab Initio Studies of Calcium Carbonate Hydration.

    PubMed

    Lopez-Berganza, Josue A; Diao, Yijue; Pamidighantam, Sudhakar; Espinosa-Marzal, Rosa M

    2015-11-25

    Ab initio simulations of large hydrated calcium carbonate clusters are challenging due to the existence of multiple local energy minima. Extensive conformational searches around hydrated calcium carbonate clusters (CaCO3·nH2O for n = 1-18) were performed to find low-energy hydration structures using an efficient combination of Monte Carlo searches, density-functional tight binding (DFTB+) method, and density-functional theory (DFT) at the B3LYP level, or Møller-Plesset perturbation theory at the MP2 level. This multilevel optimization yields several low-energy structures for hydrated calcium carbonate. Structural and energetics analysis of the hydration of these clusters revealed a first hydration shell composed of 12 water molecules. Bond-length and charge densities were also determined for different cluster sizes. The solvation of calcium carbonate in bulk water was investigated by placing the explicitly solvated CaCO3·nH2O clusters in a polarizable continuum model (PCM). The findings of this study provide new insights into the energetics and structure of hydrated calcium carbonate and contribute to the understanding of mechanisms where calcium carbonate formation or dissolution is of relevance. PMID:26505205

  2. Ab initio two-component Ehrenfest dynamics

    SciTech Connect

    Ding, Feizhi; Goings, Joshua J.; Liu, Hongbin; Lingerfelt, David B.; Li, Xiaosong

    2015-09-21

    We present an ab initio two-component Ehrenfest-based mixed quantum/classical molecular dynamics method to describe the effect of nuclear motion on the electron spin dynamics (and vice versa) in molecular systems. The two-component time-dependent non-collinear density functional theory is used for the propagation of spin-polarized electrons while the nuclei are treated classically. We use a three-time-step algorithm for the numerical integration of the coupled equations of motion, namely, the velocity Verlet for nuclear motion, the nuclear-position-dependent midpoint Fock update, and the modified midpoint and unitary transformation method for electronic propagation. As a test case, the method is applied to the dissociation of H{sub 2} and O{sub 2}. In contrast to conventional Ehrenfest dynamics, this two-component approach provides a first principles description of the dynamics of non-collinear (e.g., spin-frustrated) magnetic materials, as well as the proper description of spin-state crossover, spin-rotation, and spin-flip dynamics by relaxing the constraint on spin configuration. This method also holds potential for applications to spin transport in molecular or even nanoscale magnetic devices.

  3. Full Dimensional Vibrational Calculations for Methane Using AN Accurate New AB Initio Based Potential Energy Surface

    NASA Astrophysics Data System (ADS)

    Majumder, Moumita; Dawes, Richard; Wang, Xiao-Gang; Carrington, Tucker; Li, Jun; Guo, Hua; Manzhos, Sergei

    2014-06-01

    New potential energy surfaces for methane were constructed, represented as analytic fits to about 100,000 individual high-level ab initio data. Explicitly-correlated multireference data (MRCI-F12(AE)/CVQZ-F12) were computed using Molpro [1] and fit using multiple strategies. Fits with small to negligible errors were obtained using adaptations of the permutation-invariant-polynomials (PIP) approach [2,3] based on neural-networks (PIP-NN) [4,5] and the interpolative moving least squares (IMLS) fitting method [6] (PIP-IMLS). The PESs were used in full-dimensional vibrational calculations with an exact kinetic energy operator by representing the Hamiltonian in a basis of products of contracted bend and stretch functions and using a symmetry adapted Lanczos method to obtain eigenvalues and eigenvectors. Very close agreement with experiment was produced from the purely ab initio PESs. References 1- H.-J. Werner, P. J. Knowles, G. Knizia, 2012.1 ed. 2012, MOLPRO, a package of ab initio programs. see http://www.molpro.net. 2- Z. Xie and J. M. Bowman, J. Chem. Theory Comput 6, 26, 2010. 3- B. J. Braams and J. M. Bowman, Int. Rev. Phys. Chem. 28, 577, 2009. 4- J. Li, B. Jiang and Hua Guo, J. Chem. Phys. 139, 204103 (2013). 5- S Manzhos, X Wang, R Dawes and T Carrington, JPC A 110, 5295 (2006). 6- R. Dawes, X-G Wang, A.W. Jasper and T. Carrington Jr., J. Chem. Phys. 133, 134304 (2010).

  4. Motion planning for multiple moving objects

    SciTech Connect

    Hwang, Y.K.

    1995-05-01

    We present a motion planner for multiple moving objects in two dimensions. The search for collision-free paths is performed in the composite configuration space of all the moving objects to guarantee a solution, and the efficiency of our planner is demonstrated with examples. Our motion planner can be characterized with a hierarchical, multi-resolution search of the configuration space along with a generate-and-test paradigm for solution paths. Because of the high dimensionality of the composite configuration space, our planner is most useful for cases with a small number of moving objects. Some of the potential applications are navigation of several mobile robots, and planning part motions for a multi-handed assembly operation.

  5. A Note on Trapping Moving Vortices

    NASA Technical Reports Server (NTRS)

    Kao, Hsiao C.

    2000-01-01

    The topic of stationary configurations of point vortices, also known as vortex equilibrium, has received considerable attention in recent years. By observing numerical results, it is found that a "counterpart" of this system also exists, in which moving vortices may be "trapped" by an inlet-like device to form a stationary pattern with no translational motion. After an intuitive explanation for the process, vortex trajectory maps based on numerical results are presented. These maps exhibit two stationary points under the present conditions, which are the focal points of vortex trajectories. A vortex upstream of these points, if within a certain offset range, will move towards these points spontaneously and be captured there. This proposed device is also capable of trapping spinning vortex pairs and triads. It is possible to impose a uniform stream at infinity, as long as the flow field is still dominated by the moving vortices.

  6. An hybrid computing approach to accelerating the multiple scattering theory based ab initio methods

    NASA Astrophysics Data System (ADS)

    Wang, Yang; Stocks, G. Malcolm

    2014-03-01

    The multiple scattering theory method, also known as the Korringa-Kohn-Rostoker (KKR) method, is considered an elegant approach to the ab initio electronic structure calculation for solids. Its convenience in accessing the one-electron Green function has led to the development of locally-self consistent multiple scattering (LSMS) method, a linear scaling ab initio method that allows for the electronic structure calculation for complex structures requiring tens of thousands of atoms in unit cell. It is one of the few applications that demonstrated petascale computing capability. In this presentation, we discuss our recent efforts in developing a hybrid computing approach for accelerating the full potential electronic structure calculation. Specifically, in the framework of our existing LSMS code in FORTRAN 90/95, we explore the many core resources on GPGPU accelerators by implementing the compute intensive functions (for the calculation of multiple scattering matrices and the single site solutions) in CUDA, and move the computational tasks to the GPGPUs if they are found available. We explain in details our approach to the CUDA programming and the code structure, and show the speed-up of the new hybrid code by comparing its performances on CPU/GPGPU and on CPU only. The work was supported in part by the Center for Defect Physics, a DOE-BES Energy Frontier Research Center.

  7. Detecting slow moving targets in SAR images

    NASA Astrophysics Data System (ADS)

    Linnehan, Robert; Perlovsky, Leonid; Mutz, Chris W.; Schindler, John

    2004-08-01

    Ground moving target indication (GMTI) radars can detect slow-moving targets if their velocities are high enough to produce distinguishable Doppler frequencies. However, no reliable technique is currently available to detect targets that fall below the minimum detectable velocity (MDV) of GMTI radars. In synthetic aperture radar (SAR) images, detection of moving targets is difficult because of target smear due to motion, which could make low-RCS targets fall below stationary ground clutter. Several techniques for SAR imaging of moving targets have been discussed in the literature. These techniques require sufficient signal-to-clutter ratio (SCR) and adequate MDV for pre-detection. Other techniques require complex changes in hardware. Extracting the maximum information from SAR image data is possible using adaptive, model-based approaches. However, these approaches lead to computational complexity, which exceeds current processing power for more than a single object in an image. This combinatorial complexity is due to the need for having to consider a large number of combinations between multiple target models and the data, while estimating unknown parameters of the target models. We are developing a technique for detecting slow-moving targets in SAR images with low signal-to-clutter ratio, without minimal velocity requirements, and without combinatorial complexity. This paper briefly summarizes the difficulties related to current model-based detection algorithms. A new concept, dynamic logic, is introduced along with an algorithm suitable for the detection of very slow-moving targets in SAR images. This new mathematical technique is inspired by the analysis of biological systems, like the human brain, which combines conceptual understanding with emotional evaluation and overcomes the combinatorial complexity of model-based techniques.

  8. H2, HD, and CO at the edge of 30 Dor in the LMC: The line of sight to Sk-69 246

    NASA Astrophysics Data System (ADS)

    Bluhm, H.; de Boer, K. S.

    2001-11-01

    FUSE and IUE observations of Sk-69 246, a WN 6 star to the north of 30 Dor, reveal the existence of LMC interstellar gas in at least 3 velocity components. In one of these components FUSE spectra show strong absorption by molecular hydrogen with a column density of log N(H_2)=19.6. We investigate the physical conditions in this cloud, which is probably located near the H Ii region surrounding Sk-69 246. HD and CO with column densities of ~ 13.9 and 13.0, respectively, are detected. The N(CO)-to-N(H2) ratio is consistent with values found in the Galaxy. From the population of the rotational levels of H2 we derive a gas temperature of 72 K and a radiation field U 3x10-15 erg s-1 cm-3 at 1000 Å. The fractional abundance f=2N(H2)/[N(ion {HI})+2N(H2)] ~0.07 is rather high for an E(B-V) <~ 0.1. Based on observations made with the NASA-CNES-CSA Far Ultraviolet Spectroscopic Explorer, available in the public archive. FUSE is operated for NASA by the Johns Hopkins University under NASA contract NAS5-32985.

  9. Metabolic Consequences of Infection of Grapevine (Vitis vinifera L.) cv. “Modra frankinja” with Flavescence Dorée Phytoplasma

    PubMed Central

    Prezelj, Nina; Covington, Elizabeth; Roitsch, Thomas; Gruden, Kristina; Fragner, Lena; Weckwerth, Wolfram; Chersicola, Marko; Vodopivec, Maja; Dermastia, Marina

    2016-01-01

    Flavescence dorée, caused by the quarantine phytoplasma FDp, represents the most devastating of the grapevine yellows diseases in Europe. In an integrated study we have explored the FDp–grapevine interaction in infected grapevines of cv. “Modra frankinja” under natural conditions in the vineyard. In FDp-infected leaf vein-enriched tissues, the seasonal transcriptional profiles of 14 genes selected from various metabolic pathways showed an FDp-specific plant response compared to other grapevine yellows and uncovered a new association of the SWEET17a vacuolar transporter of fructose with pathogens. Non-targeted metabolome analysis from leaf vein-enriched tissues identified 22 significantly changed compounds with increased levels during infection. Several metabolites corroborated the gene expression study. Detailed investigation of the dynamics of carbohydrate metabolism revealed significant accumulation of sucrose and starch in the mesophyll of FDp-infected leaves, as well as significant up-regulation of genes involved in their biosynthesis. In addition, infected leaves had high activities of ADP-glucose pyrophosphorylase and, more significantly, sucrose synthase. The data support the conclusion that FDp infection inhibits phloem transport, resulting in accumulation of carbohydrates and secondary metabolites that provoke a source-sink transition and defense response status. PMID:27242887

  10. LAMP assay and rapid sample preparation method for on-site detection of flavescence dorée phytoplasma in grapevine

    PubMed Central

    Kogovšek, P; Hodgetts, J; Hall, J; Prezelj, N; Nikolić, P; Mehle, N; Lenarčič, R; Rotter, A; Dickinson, M; Boonham, N; Dermastia, M; Ravnikar, M

    2015-01-01

    In Europe the most devastating phytoplasma associated with grapevine yellows (GY) diseases is a quarantine pest, flavescence dorée (FDp), from the 16SrV taxonomic group. The on-site detection of FDp with an affordable device would contribute to faster and more efficient decisions on the control measures for FDp. Therefore, a real-time isothermal LAMP assay for detection of FDp was validated according to the EPPO standards and MIQE guidelines. The LAMP assay was shown to be specific and extremely sensitive, because it detected FDp in all leaf samples that were determined to be FDp infected using quantitative real-time PCR. The whole procedure of sample preparation and testing was designed and optimized for on-site detection and can be completed in one hour. The homogenization procedure of the grapevine samples (leaf vein, flower or berry) was optimized to allow direct testing of crude homogenates with the LAMP assay, without the need for DNA extraction, and was shown to be extremely sensitive. PMID:26146413

  11. Excited Protein States of Human Tear Lipocalin for Low- and High-Affinity Ligand Binding Revealed by Functional AB Loop Motion

    PubMed Central

    Gasymov, Oktay K.; Abduragimov, Adil R.; Glasgow, Ben J.

    2010-01-01

    Human tear lipocalin (TL), a prominent member of lipocalin family, exhibits functional and structural promiscuity. The plasticity of loop regions modulates entry to the ligand pocket at the “open” end of the eight-stranded β-barrel. Site directed multi-distance measurements using fluorescence resonance energy transfer between functional loops register two excited protein states for low- and high-affinity ligand binding. At low pH, the longest loop AB adopts the conformation of the low-affinity excited protein state that matches the crystal structure of holo-TL at pH 8. A “crankshaft” like movement is detected for the loop AB in a low pH transition. At pH 7.3 the holo-protein assumes a high-affinity excited protein state, in which the loop AB is more compact (RMS= 3.1Å). In the apo-holo transition, the reporter Trp 28 moves about 4.5 Å that reflects a decrease in distance between Glu27 and Lys108. This interaction fixes the loop AB conformation for the high-affinity mode. No such of movement is detected at low pH, where Glu27 is protonated. Data strongly indicate that the protonation state of Glu27 modulates the conformation of the loop AB for high- and low-affinity binding. PMID:20439130

  12. Excited protein states of human tear lipocalin for low- and high-affinity ligand binding revealed by functional AB loop motion.

    PubMed

    Gasymov, Oktay K; Abduragimov, Adil R; Glasgow, Ben J

    2010-06-01

    Human tear lipocalin (TL), a prominent member of lipocalin family, exhibits functional and structural promiscuity. The plasticity of loop regions modulates entry to the ligand pocket at the "open" end of the eight-stranded beta-barrel. Site-directed multi-distance measurements using fluorescence resonance energy transfer between functional loops register two excited protein states for low- and high-affinity ligand binding. At low pH, the longest loop AB adopts the conformation of the low-affinity excited protein state that matches the crystal structure of holo-TL at pH 8. A "crankshaft" like movement is detected for the loop AB in a low pH transition. At pH 7.3 the holo-protein assumes a high-affinity excited protein state, in which the loop AB is more compact (RMS=3.1A). In the apo-holo transition, the reporter Trp 28 moves about 4.5A that reflects a decrease in distance between Glu27 and Lys108. This interaction fixes the loop AB conformation for the high-affinity mode. No such movement is detected at low pH, where Glu27 is protonated. Data strongly indicate that the protonation state of Glu27 modulates the conformation of the loop AB for high- and low-affinity binding. PMID:20439130

  13. ELECTROMAGNETIC APPARATUS FOR MOVING A ROD

    DOEpatents

    Young, J.N.

    1958-04-22

    An electromagnetic apparatus for moving a rod-like member in small steps in either direction is described. The invention has particular application in the reactor field where the reactor control rods must be moved only a small distance and where the use of mechanical couplings is impractical due to the high- pressure seals required. A neutron-absorbing rod is mounted in a housing with gripping uaits that engage the rod, and coils for magnetizing the gripping units to make them grip, shift, and release the rod are located outside the housing.

  14. Noninterferometric topography measurements of fast moving surfaces.

    PubMed

    Pinhasi, Shirly Vinikman; Eliezer, Shalom; Glam, Benny; Appelbaum, Gabi; Bakshi, Lior

    2011-08-01

    The topography of moving surfaces is recovered by noninterferometric measurements. The phase reconstruction is derived by measuring the intensities of a backscattered pulsed laser light and solving the transport intensity equation (TIE). The TIE is solved by expanding the phase into a series of Zernike polynomials, leading to a set of appropriate algebraic equations. This technique, which enables us to make a direct connection between experiments and the TIE, has been successfully tested in gas gun experiments. In particular, the topographies of a moving projectile and the free surface of a shocked target were recovered. PMID:21811317

  15. Ab initio derivation of model energy density functionals

    NASA Astrophysics Data System (ADS)

    Dobaczewski, Jacek

    2016-08-01

    I propose a simple and manageable method that allows for deriving coupling constants of model energy density functionals (EDFs) directly from ab initio calculations performed for finite fermion systems. A proof-of-principle application allows for linking properties of finite nuclei, determined by using the nuclear nonlocal Gogny functional, to the coupling constants of the quasilocal Skyrme functional. The method does not rely on properties of infinite fermion systems but on the ab initio calculations in finite systems. It also allows for quantifying merits of different model EDFs in describing the ab initio results.

  16. Real-time detection of moving objects from moving vehicles using dense stereo and optical flow

    NASA Technical Reports Server (NTRS)

    Talukder, Ashit; Matthies, Larry

    2004-01-01

    Dynamic scene perception is very important for autonomous vehicles operating around other moving vehicles and humans. Most work on real-time object tracking from moving platforms has used sparse features or assumed flat scene structures. We have recently extended a real-time, dense stereo system to include real-time, dense optical flow, enabling more comprehensive dynamic scene analysis. We describe algorithms to robustly estimate 6-DOF robot egomotion in the presence of moving objects using dense flow and dense stereo. We then use dense stereo and egomotion estimates to identity other moving objects while the robot itself is moving. We present results showing accurate egomotion estimation and detection of moving people and vehicles under general 6-DOF motion of the robot and independently moving objects. The system runs at 18.3 Hz on a 1.4 GHz Pentium M laptop, computing 160x120 disparity maps and optical flow fields, egomotion, and moving object segmentation. We believe this is a significant step toward general unconstrained dynamic scene analysis for mobile robots, as well as for improved position estimation where GPS is unavailable.

  17. Real-time detection of moving objects from moving vehicles using dense stereo and optical flow

    NASA Technical Reports Server (NTRS)

    Talukder, Ashit; Matthies, Larry

    2004-01-01

    Dynamic scene perception is very important for autonomous vehicles operating around other moving vehicles and humans. Most work on real-time object tracking from moving platforms has used sparse features or assumed flat scene structures. We have recently extended a real-time, dense stereo system to include realtime, dense optical flow, enabling more comprehensive dynamic scene analysis. We describe algorithms to robustly estimate 6-DOF robot egomotion in the presence of moving objects using dense flow and dense stereo. We then use dense stereo and egomotion estimates to identify & other moving objects while the robot itself is moving. We present results showing accurate egomotion estimation and detection of moving people and vehicles under general 6-DOF motion of the robot and independently moving objects. The system runs at 18.3 Hz on a 1.4 GHz Pentium M laptop, computing 160x120 disparity maps and optical flow fields, egomotion, and moving object segmentation. We believe this is a significant step toward general unconstrained dynamic scene analysis for mobile robots, as well as for improved position estimation where GPS is unavailable.

  18. Real-time Detection of Moving Objects from Moving Vehicles Using Dense Stereo and Optical Flow

    NASA Technical Reports Server (NTRS)

    Talukder, Ashit; Matthies, Larry

    2004-01-01

    Dynamic scene perception is very important for autonomous vehicles operating around other moving vehicles and humans. Most work on real-time object tracking from moving platforms has used sparse features or assumed flat scene structures. We have recently extended a real-time. dense stereo system to include realtime. dense optical flow, enabling more comprehensive dynamic scene analysis. We describe algorithms to robustly estimate 6-DOF robot egomotion in the presence of moving objects using dense flow and dense stereo. We then use dense stereo and egomotion estimates to identify other moving objects while the robot itself is moving. We present results showing accurate egomotion estimation and detection of moving people and vehicles under general 6DOF motion of the robot and independently moving objects. The system runs at 18.3 Hz on a 1.4 GHz Pentium M laptop. computing 160x120 disparity maps and optical flow fields, egomotion, and moving object segmentation. We believe this is a significant step toward general unconstrained dynamic scene analysis for mobile robots, as well as for improved position estimation where GPS is unavailable.

  19. Motion of a Moving Elastic Beam Carrying a Moving MASS—ANALYSIS and Experimental Verification

    NASA Astrophysics Data System (ADS)

    PARK, S.; YOUM, Y.

    2001-02-01

    In this paper, vibrational motion of an elastic beam fixed on a moving cart and carrying a moving mass is investigated. The equations of motion of the beam-mass-cart system are derived and the coupled dynamic equations are solved by the unconstrained modal analysis. In modal analysis, the exact normal mode solutions corresponding to the eigenfrequencies for each position of the moving mass and the ratios of the weight of the beam-mass-cart system are used. Proper transformation of time solutions between the normal modes for a position and those for the next position of the moving mass is also considered. Numerical simulations are carried out to obtain open-loop responses of the system in tracking pre-designed paths of the moving mass. The simulation results show that the model predicts the dynamic behavior of the beam-mass-cart system well. Experiments are carried out to show the validity of the proposed analytical method.

  20. The effect of monocular depth cues on the detection of moving objects by moving observers.

    PubMed

    Royden, Constance S; Parsons, Daniel; Travatello, Joshua

    2016-07-01

    An observer moving through the world must be able to identify and locate moving objects in the scene. In principle, one could accomplish this task by detecting object images moving at a different angle or speed than the images of other items in the optic flow field. While angle of motion provides an unambiguous cue that an object is moving relative to other items in the scene, a difference in speed could be due to a difference in the depth of the objects and thus is an ambiguous cue. We tested whether the addition of information about the distance of objects from the observer, in the form of monocular depth cues, aided detection of moving objects. We found that thresholds for detection of object motion decreased as we increased the number of depth cues available to the observer. PMID:27264029

  1. Use of moving interference fringes for holographic recording onto a moving storage medium.

    PubMed

    Tatemichi, H; Yamamoto, M

    1993-07-10

    We describe a feasibility study of a multiplexed holographic recording method onto a moving storage medium by using moving interference fringes caused by diffracted light beams that are generated from an acousto-optic deflector (AOD). The AOD, driven by amplitude-modulated electric signals, generates several diffracted beams with different frequencies because of Doppler shifting by AOD driving-frequency components. The interference between the beams results in a nonstationary light intensity distribution, i.e., a moving interference fringe. Its velocity is reduced by an image-reduction optical system, and the storage medium is moved at the same velocity as the fringe motion at the image-formation point. This compensates for a reduction of visibility with the movement of the medium, so a holographic recording onto a moving medium can be achieved. In addition, angular multiplexing is achieved by switching the AOD driving frequencies. PMID:20829997

  2. Skutterudites under pressure: An ab initio study

    SciTech Connect

    Ram, Swetarekha; Kanchana, V.; Valsakumar, M. C.

    2014-03-07

    Ab initio results on the band structure, density of states, and Fermi surface (FS) properties of LaRu{sub 4}X{sub 12} (X = P, As, Sb) are presented at ambient pressure as well as under compression. The analysis of density of states reveals the major contribution at the Fermi level to be mainly from the Ru-d and X-p states. We have a complicated Fermi surface with both electron and hole characters for all the three compounds which is derived mainly from the Ru-d and X-p states. There is also a simpler FS with hole character derived from the P-p{sub z} orbital for LaRu{sub 4}P{sub 12} and Ru-d{sub z{sup 2}} orbital in the case of As and Sb containing compounds. More interestingly, Fermi surface nesting feature is observed only in the case of the LaRu{sub 4}P{sub 12}. Under compression, we observe the topology of the complicated FS sheet of LaRu{sub 4}As{sub 12} to change around V/V{sub 0} = 0.85, leading to a behaviour similar to that of a multiband superconductor, and in addition, we have two more hole pockets centered around Γ at V/V{sub 0} = 0.8 for the same compound. Apart from this, we find the hole pocket to vanish at V/V{sub 0} = 0.8 in the case of LaRu{sub 4}Sb{sub 12} and the opening of the complicated FS sheet gets reduced. The de Haas van Alphen calculation shows the number of extremal orbits in the complicated sheet to change in As and Sb containing compounds under compression, where we also observe the FS topology to change.

  3. Magnetic multipole redirector of moving plasmas

    DOEpatents

    Crow, James T.; Mowrer, Gary R.

    1999-01-01

    A method and apparatus for redirecting moving plasma streams using a multiple array of magnetic field generators (e.g., permanent magnets or current bearing wires). Alternate rows of the array have opposite magnetic field directions. A fine wire mesh may be employed to focus as well as redirect the plasma.

  4. Electromagnetic Force on a Moving Dipole

    ERIC Educational Resources Information Center

    Kholmetskii, Alexander L.; Missevitch, Oleg V.; Yarman, T.

    2011-01-01

    We analyse the force acting on a moving dipole due to an external electromagnetic field and show that the expression derived in Vekstein (1997 "Eur. J. Phys." 18 113) is erroneous and suggest the correct equation for the description of this force. We also discuss the physical meaning of the relativistic transformation of current for a closed…

  5. Bacterial Chemotaxis with a Moving Target

    NASA Astrophysics Data System (ADS)

    Dominick, Corey

    2015-03-01

    Most chemotaxis studies so far have been conducted in a quiescent fluid with a well-defined chemical gradient. Such experiments may be appropriate for studying enteric bacteria, such as Escherichia coli, but the environment it provides is very different from that typically encountered by marine bacteria. Herein we describe an experiment in which marine bacterium Vibrio alginolyticusis subject to stimulation by a small moving target. A micropipette of the tip size <1 ?m is used to slowly release a chemoattractant, serine, at different concentrations. The pipette is made to move with different patterns and speeds, ranging from 0 to 100 ?m/s; the latter is about twice the bacterial swimming speed. We found that if the pipette is moved slowly, with 1/4 of bacterial swimming speed, cells accumulate near the tip region but when it is moved with speed greater than 1/2 the bacterial swimming speed, cells trail behind the pipette over a large distance. The behaviors observed in V. alginolyticusare significantly different from E. coli, suggesting that the former is a better chemotaxer in a changing environment.

  6. Supportive Discourse Moves in Persian Requests

    ERIC Educational Resources Information Center

    Nodoushan, Mohammad Ali Salmani; Allami, Hamid

    2011-01-01

    This paper reports the findings of a study designed to investigate the types of supportive discourse moves employed by Persian speakers in their Requestive Speech Acts. 372 respondents took a Discourse Completion Test (DCT) with six scenarios ranging from formal to informal degrees of Perceived Situational Seriousness, and returned 2232 Requestive…

  7. Optimizing replica exchange moves for molecular dynamics.

    PubMed

    Nadler, Walter; Hansmann, Ulrich H E

    2007-11-01

    We sketch the statistical physics framework of the replica exchange technique when applied to molecular dynamics simulations. In particular, we draw attention to generalized move sets that allow a variety of optimizations as well as new applications of the method. PMID:18233794

  8. Moving Divertor Plates in a Tokamak

    SciTech Connect

    S.J. Zweben, H. Zhang

    2009-02-12

    Moving divertor plates could help solve some of the problems of the tokamak divertor through mechanical ingenuity rather than plasma physics. These plates would be passively heated on each pass through the tokamak and cooled and reprocessed outside the tokamak. There are many design options using varying plate shapes, orientations, motions, coatings, and compositions.

  9. On the Move: Children in Transition.

    ERIC Educational Resources Information Center

    Miller, Yaffa F.; Cherry, Jane W.

    This monograph focuses on children who must move to a new school and new surroundings because their family, for whatever reason, is relocating. It notes that the impact of mobility on families has practical implications for public schools and that schools with a large number of mobile students have a responsibility to establish structured programs…

  10. What Moves Me to Act. I.

    ERIC Educational Resources Information Center

    Carlson, Robert

    In this speech, the author expresses concern for the child who does not seem able to perform. The author states that there is an orderly acquisition of sensations, skills, and/or patterns that we move through in the process of learning, and that the acquisition of more advanced skills is predicted on the assumption that earlier sensations, skills,…

  11. Strategic Game Moves Mediate Implicit Science Learning

    ERIC Educational Resources Information Center

    Rowe, Elizabeth; Baker, Ryan S.; Asbell-Clarke, Jodi

    2015-01-01

    Educational games have the potential to be innovative forms of learning assessment, by allowing us to not just study their knowledge but the process that takes students to that knowledge. This paper examines the mediating role of players' moves in digital games on changes in their pre-post classroom measures of implicit science learning. We…

  12. Home Visiting: Looking Back and Moving Forward

    ERIC Educational Resources Information Center

    Boller, Kimberly; Strong, Debra A.; Daro, Deborah

    2010-01-01

    Recent large federal investments in services for pregnant women and young children will fuel the expansion of home visiting services across the U.S. The authors summarize the history of home visiting and describe trends toward evidence-based and national program models. Moving to an integrated system requires supports for implementation with…

  13. Finding Funds to Move Summer Learning Forward

    ERIC Educational Resources Information Center

    Seidel, Bob

    2015-01-01

    Summer learning loss creates a permanent drag on the US education system. With the generous support of the Charles Stewart Mott Foundation, the National Summer Learning Association (NSLA) developed "Moving Summer Learning Forward: A Strategic Roadmap for Funding in Tough Times" to provide out-of-school time programs, school districts,…

  14. Moving toward Gender Equality: Issues and Implications.

    ERIC Educational Resources Information Center

    Baldwin, Cynthia

    1993-01-01

    Examines society's orientation toward a dominator model of interaction and discusses it within the context of history. Articulates conscious choices counselors can make to move toward a more equitable and humanistic style of interpersonal interaction. Concludes that vital struggle between dominance and partnership is struggle for both men and…

  15. Developing Reading Comprehension with Moving Image Narratives

    ERIC Educational Resources Information Center

    Maine, Fiona; Shields, Robin

    2015-01-01

    This paper reports the findings from a small-scale exploratory study that investigated how moving-image narratives might enable children to develop transferable reading comprehension strategies. Using short, animated, narrative films, 28 primary-aged children engaged in a 10-week programme that included the explicit instruction of comprehension…

  16. What Moves Me to Act? II.

    ERIC Educational Resources Information Center

    Cherry, Clare

    This speaker contends that many learning problems can be prevented, or at least lessened, by early intervention. This knowledge is what moves her to act. She describes how, while tutoring bright but nonachieving children in reading, she realized that it was the opportunities she provided the children for visual-motor perceptual training that were…

  17. Moving On: Young People and Substance Abuse

    ERIC Educational Resources Information Center

    Daley, Kathryn; Chamberlain, Chris

    2009-01-01

    To help explain why some young people move from recreational drug use to substance abuse, twelve in-depth interviews were conducted with young people who had experienced problematic substance use. The data were supplemented by statistical data on 111 young people. The researchers found a variety of "structural" factors that help explain young…

  18. Panel Moves toward "Next Generation" Science Standards

    ERIC Educational Resources Information Center

    Robelen, Erik W.

    2010-01-01

    As part of a national effort to produce "next generation" science standards for K-12 education, a panel of experts convened by the National Research Council (NRC) has issued a draft of a conceptual framework designed to guide the standards and "move science education toward a more coherent vision." One key goal of the effort is to focus science…

  19. Moving, Moving, Moving About.

    ERIC Educational Resources Information Center

    Pounds, Elenore T.; Tillotson, Joan S.

    The topic of this book is movement education. The book encourages children to explore and use such basic movements as walking, running, jumping, hopping, bending, and stretching. The children are asked to do the various movements in as many ways as possible. Poems about jumping, hopping, and dancing are included to encourage the children to move…

  20. Ab Initio: And a New Era of Airline Pilot Training.

    ERIC Educational Resources Information Center

    Gesell, Laurence E.

    1995-01-01

    Expansion of air transportation and decreasing numbers seeking pilot training point to a shortage of qualified pilots. Ab initio training, in which candidates with no flight time are trained to air transport proficiency, could resolve the problem. (SK)

  1. Tensile deformation mechanisms of ABS/PMMA/EMA blends

    NASA Astrophysics Data System (ADS)

    Wang, S. H.; Gao, J.; Lin, S. X.; Zhang, P.; Huang, J.; Xu, L. L.

    2014-08-01

    The tensile deformation mechanisms of acrylonitrile - butadiene - styrene (ABS) / polymethyl methacrylate (PMMA) blends toughened by ethylene methacrylate (EMA) copolymer was investigated by analysing the fracture morphology. ABS/PMMA was blended with EMA copolymer by melt mixing technique using co-rotating twin extruder. Tensile tests show that the elongation at break of ABS/PMMA blends can be efficiently improved with the increase in EMA content. Fracture morphology of ABS/PMMA/EMA blends reveals that the material yield induced by hollowing-out of EMA particles and its propagation into yield zone is the main toughening mechanism. Moreover, the appearance that EMA particles in the central area are given priority to hollowing-out may be related to the skin-core structure of the injection moulded parts caused by the different cooling rate between surface and inside in the process of injection moulding.

  2. Effect of electric field on the mechanical properties of bilayer boron nitride with AB stacking order: An ab initio study

    NASA Astrophysics Data System (ADS)

    Ansari, R.; Faghihnasiri, M.; Malakpour, S.; Sahmani, S.

    2015-07-01

    In the current investigation, ab initio calculations are performed to explore the influence of electric field on the mechanical properties of bilayer boron nitride with AB stacking order (AB-2LBN). To accomplish this, density functional theory (DFT) within the framework of generalized gradient approximation (GGA) is implemented. It is demonstrated that the electric field has significant effects on Young's modulus and Poisson's ratio of AB-2LBN when its magnitude is small. With increasing the magnitude of electric field, these effects diminish so that the mechanical properties with and without considering the electric field become approximately identical. Also, it is shown that the equilibrium strain energy decreases linearly by increasing the magnitude of applied electric field.

  3. Ab-initio calculation of electronic structure and optical properties of AB-stacked bilayer α-graphyne

    NASA Astrophysics Data System (ADS)

    Behzad, Somayeh

    2016-09-01

    Monolayer α-graphyne is a new two-dimensional carbon allotrope with many special features. In this work the electronic properties of AA- and AB-stacked bilayers of this material and then the optical properties are studied, using first principle plane wave method. The electronic spectrum has two Dirac cones for AA stacked bilayer α-graphyne. For AB-stacked bilayer, the interlayer interaction changes the linear bands into parabolic bands. The optical spectra of the most stable AB-stacked bilayer closely resemble to that of the monolayer, except for small shifts of peak positions and increasing of their intensity. For AB-stacked bilayer, a pronounced peak has been found at low energies under the perpendicular polarization. This peak can be clearly ascribed to the transitions at the Dirac point as a result of the small degeneracy lift in the band structure.

  4. Ab Initio No-Core Shell Model

    SciTech Connect

    Barrett, B R; Navratil, P; Vary, J P

    2011-04-11

    A long-standing goal of nuclear theory is to determine the properties of atomic nuclei based on the fundamental interactions among the protons and neutrons (i.e., nucleons). By adopting nucleon-nucleon (NN), three-nucleon (NNN) and higher-nucleon interactions determined from either meson-exchange theory or QCD, with couplings fixed by few-body systems, we preserve the predictive power of nuclear theory. This foundation enables tests of nature's fundamental symmetries and offers new vistas for the full range of complex nuclear phenomena. Basic questions that drive our quest for a microscopic predictive theory of nuclear phenomena include: (1) What controls nuclear saturation; (2) How the nuclear shell model emerges from the underlying theory; (3) What are the properties of nuclei with extreme neutron/proton ratios; (4) Can we predict useful cross sections that cannot be measured; (5) Can nuclei provide precision tests of the fundamental laws of nature; and (6) Under what conditions do we need QCD to describe nuclear structure, among others. Along with other ab initio nuclear theory groups, we have pursued these questions with meson-theoretical NN interactions, such as CD-Bonn and Argonne V18, that were tuned to provide high-quality descriptions of the NN scattering phase shifts and deuteron properties. We then add meson-theoretic NNN interactions such as the Tucson-Melbourne or Urbana IX interactions. More recently, we have adopted realistic NN and NNN interactions with ties to QCD. Chiral perturbation theory within effective field theory ({chi}EFT) provides us with a promising bridge between QCD and hadronic systems. In this approach one works consistently with systems of increasing nucleon number and makes use of the explicit and spontaneous breaking of chiral symmetry to expand the strong interaction in terms of a dimensionless constant, the ratio of a generic small momentum divided by the chiral symmetry breaking scale taken to be about 1 GeV/c. The resulting NN

  5. Moving to a New Town. A Relocation Guide.

    ERIC Educational Resources Information Center

    Rackliffe, Gary, Ed.; Pearson, Nancy, Ed.

    Designed to help those who must consider relocating to secure employment, this relocation guide provides answers to a number of questions pertaining to moving, money management, and adjusting to a new community. Various aspects of deciding to move are covered, including reasons for moving, thinking of a move as permanent, feelings of homesickness,…

  6. Move Sequences in Graduate Research Paper Introductions and Conclusions

    ERIC Educational Resources Information Center

    Madrunio, Marilu Rañosa

    2012-01-01

    Graduate students submit academic papers at the end of the term as part of their coursework. Such papers contain introduction moves which may be troublesome and conclusion moves which may contain sub-moves not really required. This paper is aimed at assessing what particular moves are employed in the introduction and conclusion sections of 21…

  7. Concentrations of AB-CHMINACA and AB-PINACA and Driving Behavior in Suspected Impaired Driving Cases.

    PubMed

    Peterson, Brianna L; Couper, Fiona J

    2015-10-01

    This article reviews case reports for 58 suspected impaired driving cases that were positive for the synthetic cannabinoids AB-CHMINACA or AB-PINACA. All cases were submitted to the Washington State Patrol Toxicology Laboratory in 2014 from either Washington State or State of Alaska law enforcement agencies. The population of drivers was predominantly male (95%), with a mean age of 28 years (range, 18-61 years). The range of blood concentrations was 0.6->10 ng/mL for AB-CHMINACA (N = 33) and 0.6-41.3 ng/mL for AB-PINACA (N = 25). Drug Recognition Expert exams were performed in 10 cases for each AB-CHMINACA and AB-PINACA. Horizontal gaze nystagmus was observed in 50 and 60% of the cases, respectively. Overall, several physiological indicators varied from those typically observed with marijuana use. The majority of these cases had very poor driving; subjects were involved in an accident, found passed out in a vehicle or were called in as a suspected impaired driver. Slurred speech, confusion, lack of coordination/dexterity and lethargy were commonly observed. PMID:26378139

  8. Biostratigraphic data for the Cretaceous marine sediments in the USGS-St. George no. 1 core (DOR-211), Dorchester County, South Carolina

    USGS Publications Warehouse

    Self-Trail, Jean M.; Gohn, Gregory S.

    1997-01-01

    The USGS-St. George corehole was drilled for the U.S. Geological Survey (USGS) by a commercial drilling company during 1982. The corehole is located within the Coastal Plain Province in northern Dorchester County, South Carolina, about three miles southeast of the town of St. George near the village of Byrd (fig. 1). Coordinates for the corehole are 33o09'25'N latitude and 80o31'18'W longitude; ground elevation at the site is +78 feet (Reid and others, 1986). The St. George corehole is designated as USGS drill hole DOR-211. The St. George corehole was drilled to a total depth of 2,067 ft. The hole was cored continuously with generally good recovery from 300 ft to its total depth. Spot cores were taken at selected intervals between the top of the hole and a depth of 300 ft (50-55 ft, 100-110 ft, 150-165 ft, 200-205 ft, and 250-255 ft); however, recovery was poor in most of these intervals. The St. George core currently is stored at the USGS National Center, Reston, VA (March, 1997). The St. George corehole bottomed in basalt of probable early Mesozoic age beneath an Upper Cretaceous and Cenozoic sedi-mentary section. Reid and others (1986) placed the top of basalt saprolite at 1,962 ft in the hole. Our examination of the geophysical logs and original core descriptions suggests that the top of the saprolite is higher in the hole, at about 1,939 ft. The Cretaceous-Tertiary boundary was placed at or near 550 ft in the core by Reid and others (1986) and by Habib and Miller (1989). In this report, we provide paleontologic data for marine sediments in the upper part of the Upper Cretaceous section in the St. George core. Biostratigraphic and paleoenvironmental data and interpretations based on the study of calcareous nannofossils and ostracodes from the Cretaceous section are discussed.

  9. A Novel Bacteroidetes Symbiont Is Localized in Scaphoideus titanus, the Insect Vector of Flavescence Dorée in Vitis vinifera

    PubMed Central

    Marzorati, Massimo; Alma, Alberto; Sacchi, Luciano; Pajoro, Massimo; Palermo, Simona; Brusetti, Lorenzo; Raddadi, Noura; Balloi, Annalisa; Tedeschi, Rosemarie; Clementi, Emanuela; Corona, Silvia; Quaglino, Fabio; Bianco, Piero Attilio; Beninati, Tiziana; Bandi, Claudio; Daffonchio, Daniele

    2006-01-01

    Flavescence dorée (FD) is a grapevine disease that afflicts several wine production areas in Europe, from Portugal to Serbia. FD is caused by a bacterium, “Candidatus Phytoplasma vitis,” which is spread throughout the vineyards by a leafhopper, Scaphoideus titanus (Cicadellidae). After collection of S. titanus specimens from FD-contaminated vineyards in three different areas in the Piedmont region of Italy, we performed a survey to characterize the bacterial microflora associated with this insect. Using length heterogeneity PCR with universal primers for bacteria we identified a major peak associated with almost all of the individuals examined (both males and females). Characterization by denaturing gradient gel electrophoresis confirmed the presence of a major band that, after sequencing, showed a 97 to 99% identity with Bacteroidetes symbionts of the “Candidatus Cardinium hertigii” group. In addition, electron microscopy of tissues of S. titanus fed for 3 months on phytoplasma-infected grapevine plants showed bacterial cells with the typical morphology of “Ca. Cardinium hertigii.” This endosymbiont, tentatively designated ST1-C, was found in the cytoplasm of previtellogenic and vitellogenic ovarian cells, in the follicle cells, and in the fat body and salivary glands. In addition, cell morphologies resembling those of “Ca. Phytoplasma vitis” were detected in the midgut, and specific PCR assays indicated the presence of the phytoplasma in the gut, fat body and salivary glands. These results indicate that ST1-C and “Ca. Phytoplasma vitis” have a complex life cycle in the body of S. titanus and are colocalized in different organs and tissues. PMID:16461701

  10. On multiscale moving contact line theory

    PubMed Central

    Li, Shaofan; Fan, Houfu

    2015-01-01

    In this paper, a multiscale moving contact line (MMCL) theory is presented and employed to simulate liquid droplet spreading and capillary motion. The proposed MMCL theory combines a coarse-grained adhesive contact model with a fluid interface membrane theory, so that it can couple molecular scale adhesive interaction and surface tension with hydrodynamics of microscale flow. By doing so, the intermolecular force, the van der Waals or double layer force, separates and levitates the liquid droplet from the supporting solid substrate, which avoids the shear stress singularity caused by the no-slip condition in conventional hydrodynamics theory of moving contact line. Thus, the MMCL allows the difference of the surface energies and surface stresses to drive droplet spreading naturally. To validate the proposed MMCL theory, we have employed it to simulate droplet spreading over various elastic substrates. The numerical simulation results obtained by using MMCL are in good agreement with the molecular dynamics results reported in the literature. PMID:26345090

  11. Moving Frames for Heart Fiber Reconstruction.

    PubMed

    Piuze, Emmanuel; Sporring, Jon; Siddiqi, Kaleem

    2015-01-01

    The method of moving frames provides powerful geometrical tools for the analysis of smoothly varying frame fields. However, in the face of missing measurements, a reconstruction problem arises, one that is largely unexplored for 3D frame fields. Here we consider the particular example of reconstructing impaired cardiac diffusion magnetic resonance imaging (dMRI) data. We combine moving frame analysis with a diffusion inpainting scheme that incorporates rule-based priors. In contrast to previous reconstruction methods, this new approach uses comprehensive differential descriptors for cardiac fibers, and is able to fully recover their orientation. We demonstrate the superior performance of this approach in terms of error of fit when compared to alternate methods. We anticipate that these tools could find application in clinical settings, where damaged heart tissue needs to be replaced or repaired, and for generating dense fiber volumes in electromechanical modelling of the heart. PMID:26221700

  12. Segmentation of moving object in complex environment

    NASA Astrophysics Data System (ADS)

    Yong, Yang; Wang, Jingru; Zhang, Qiheng

    2005-02-01

    This paper presents a new automatic image segmentation method for segmenting moving object in complex environment by combining the motion information with edge information. We propose an adaptive optical flow method based on the Horn-Schunck algorithm to estimate the optical flow field. Our method puts different smoothness constraints on different directions and optical flow constraint is used according to the gradient magnitude. Canny edge detector can obtain the most edge information but miss some pixels. In order to restore these missing pixels the edge has a growing based on the continuity of optical flow field. Next, by remaining the block that has the longest edge could delete the noise in the background, and then the last segmentation result is obtained. The experimental result demonstrates that this method can segment the moving object in complex environment precisely.

  13. Real time moving scene holographic camera system

    NASA Technical Reports Server (NTRS)

    Kurtz, R. L. (Inventor)

    1973-01-01

    A holographic motion picture camera system producing resolution of front surface detail is described. The system utilizes a beam of coherent light and means for dividing the beam into a reference beam for direct transmission to a conventional movie camera and two reflection signal beams for transmission to the movie camera by reflection from the front side of a moving scene. The system is arranged so that critical parts of the system are positioned on the foci of a pair of interrelated, mathematically derived ellipses. The camera has the theoretical capability of producing motion picture holograms of projectiles moving at speeds as high as 900,000 cm/sec (about 21,450 mph).

  14. Kinetic responses of Dunaliella in moving fluids.

    PubMed

    Chengala, Ahammed Anwar; Hondzo, Miki; Troolin, Dan; Lefebvre, Paul A

    2010-09-01

    The objective of this work was to quantify the kinetic behavior of Dunaliella primolecta (D. primolecta) subjected to controlled fluid flow under laboratory conditions. In situ velocities of D. primolecta were quantified by micron-resolution particle image velocimetry and particle tracking velocimetry. Experiments were performed under a range of velocity gradients and corresponding energy dissipation levels at microscopic scales similar to the energy dissipation levels of natural aquatic ecosystems. An average swimming velocity of D. primolecta in a stagnant fluid was 41 microm/s without a preferential flow direction. In a moving fluid, the sample population velocities of D. primolecta follow a log-normal distribution. The variability of sample population velocities was maximal at the highest fluid flow velocity in the channel. Local fluid velocity gradients inhibited the accrual of D. primolecta by twofold 5 days after the initiation of the experiment in comparison to the non-moving fluid control experiment. PMID:20506336

  15. Moving and handling: reducing risk through assessment.

    PubMed

    Warren, Gemma

    2016-06-01

    Manual handling injuries can occur almost anywhere in a healthcare environment, and most staff perform a variety of moving and handling tasks every day. Heavy lifting, awkward posture, and previous or existing injury can increase the risk of musculoskeletal disorders. A healthcare professional's involvement in moving and handling is more widespread than it might appear, and their actions and understanding of techniques, legislation and guidelines have a direct effect on patient care. Every situation that involves the handling, or partial handling, of a person presents varying levels of risk to the patient and the carer. Maintaining a good level of patient mobility and independence is an essential part of care delivery and can reduce the risk of long-term physical and psychological effects. Delivery of care should focus on the individual's capacity, not their incapacity, to ensure that they are treated with dignity and respect. PMID:27275915

  16. Drop Impact on to Moving Liquid Pools

    NASA Astrophysics Data System (ADS)

    Muñoz-Sánchez, Beatriz Natividad; Castrejón-Pita, José Rafael; Castrejón-Pita, Alfonso Arturo; Hutchings, Ian M.

    2014-11-01

    The deposition of droplets on to moving liquid substrates is an omnipresent situation both in nature and industry. A diverse spectrum of phenomena emerges from this simple process. In this work we present a parametric experimental study that discerns the dynamics of the impact in terms of the physical properties of the fluid and the relative velocity between the impacting drop and the moving liquid pool. The behaviour ranges from smooth coalescence (characterized by little mixing) to violent splashing (generation of multiple satellite droplets and interfacial vorticity). In addition, transitional regimes such as bouncing and surfing are also found. We classify the system dynamics and show a parametric diagram for the conditions of each regime. This work was supported by the EPSRC (Grant EP/H018913/1), the Royal Society, Becas Santander Universidades and the International Relationships Office of the University of Extremadura.

  17. Moving mass trim control system design

    SciTech Connect

    Byrne, R.H.; Robinett, R.D.; Sturgis, B.R.

    1996-03-01

    This paper describes the design of a moving mass trim control system for maneuvering axisymmetric reentry vehicles. The moving mass trim controller is composed of three equal masses that are independently positioned in order to deliver a desired center of mass position. For a slowly spinning reentry vehicle, the mass offset creates a trim angle-of-attack to generate modest flight path corrections. The control system must maintain the desired position of each mass in the face of large disturbances. A novel algorithm for determining the desired mass positions is developed in conjunction with a preliminary controller design. The controller design is based on classical frequency domain techniques where a bound on the disturbance magnitude is used to formulate the disturbance rejection problem. Simulation results for the controller are presented for a typical reentry vehicle.

  18. A Luneburg lens in moving coordinates

    NASA Astrophysics Data System (ADS)

    Gladyshev, V. O.; Tereshin, A. A.

    2016-05-01

    The reflection of light rays by a reference microsatellite of new design, which moves with a velocity of 7500 m/s along a near-Earth orbit with a radius of 835 km, is calculated. The microsatellite is a bilayer Luneburg lens with an outer radius of 85 mm. The process of propagation of electromagnetic radiation in a Luneburg lens is analyzed for the first time with the effects of electrodynamics of moving media and optical glass dispersion taken into account. It is demonstrated that the lens motion leads to additional deflection and mixing of rays with various angles of incidence. The obtained results allow one to improve the accuracy of determination of satellite coordinates and open up new opportunities for tests of the theory of relativity and electrodynamics.

  19. Magnetic levitation system for moving objects

    DOEpatents

    Post, R.F.

    1998-03-03

    Repelling magnetic forces are produced by the interaction of a flux-concentrated magnetic field (produced by permanent magnets or electromagnets) with an inductively loaded closed electric circuit. When one such element moves with respect to the other, a current is induced in the circuit. This current then interacts back on the field to produce a repelling force. These repelling magnetic forces are applied to magnetically levitate a moving object such as a train car. The power required to levitate a train of such cars is drawn from the motional energy of the train itself, and typically represents only a percent or two of the several megawatts of power required to overcome aerodynamic drag at high speeds. 7 figs.

  20. Magnetic levitation system for moving objects

    DOEpatents

    Post, Richard F.

    1998-01-01

    Repelling magnetic forces are produced by the interaction of a flux-concentrated magnetic field (produced by permanent magnets or electromagnets) with an inductively loaded closed electric circuit. When one such element moves with respect to the other, a current is induced in the circuit. This current then interacts back on the field to produce a repelling force. These repelling magnetic forces are applied to magnetically levitate a moving object such as a train car. The power required to levitate a train of such cars is drawn from the motional energy of the train itself, and typically represents only a percent or two of the several megawatts of power required to overcome aerodynamic drag at high speeds.

  1. 77 FR 16566 - Submission for OMB Review, Comment Request, Proposed Collection: Let's Move Museums, Let's Move...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-21

    ... service that are targeted at fighting childhood obesity. The information will be used to provide... Museums, Let's Move Gardens collection was published in the Federal Register on November 16, 2011 (FR...

  2. Love waves excited by a moving source

    NASA Astrophysics Data System (ADS)

    Zaslavskii, Yu. M.

    2016-01-01

    The study analyzes the characteristics of surface Love waves excited by the moment of an oscillating torsional force with a point of action that moves uniformly and rectilinearly along the free flat boundary of a medium having the structure of a "layer on a half-space." The azimuthal-angular distribution of the amplitude and Doppler shift in frequency of the wave modes is studied as a function of the motion velocity of a vibrating source and the parameters of the medium.

  3. MicroBooNE Detector Move

    SciTech Connect

    Flemming, Bonnie; Rameika, Gina

    2014-06-25

    On Monday, June 23, 2014 the MicroBooNE detector -- a 30-ton vessel that will be used to study ghostly particles called neutrinos -- was transported three miles across the Fermilab site and gently lowered into the laboratory's Liquid-Argon Test Facility. This video documents that move, some taken with time-lapse camerad, and shows the process of getting the MicroBooNE detector to its new home.

  4. Nonholonomic feedback control among moving obstacles

    NASA Astrophysics Data System (ADS)

    Armstrong, Stephen Gregory

    A feedback controller is developed for navigating a nonholonomic vehicle in an area with multiple stationary and possibly moving obstacles. Among other applications the developed algorithms can be used for automatic parking of a passenger car in a parking lot with complex configuration or a ground robot in cluttered environment. Several approaches are explored which combine nonholonomic systems control based on sliding modes and potential field methods.

  5. The structure of a moving vortex lattice

    SciTech Connect

    Braun, D.W.; Crabtree, G.W.; Kaper, H.G.; Leaf, G.K.; Levine, D.M.; Vinokur, V.M.; Koshelev, A.E.

    1995-11-01

    Numerical solutions of the time-dependent Ginzburg-Landau equations show a new mechanism for plastic motion of a driven vortex lattice in a clean superconductor. The mechanism, which involves the creation of a defect superstructure, is intrinsic to the moving vortex lattice and is independent of bulk pinning. Other structural features found in the solutions include a reorientation of the vortex lattice and a gradual healing of lattice defects under the influence of a transport current.

  6. MicroBooNE Detector Move

    ScienceCinema

    Flemming, Bonnie; Rameika, Gina

    2014-07-15

    On Monday, June 23, 2014 the MicroBooNE detector -- a 30-ton vessel that will be used to study ghostly particles called neutrinos -- was transported three miles across the Fermilab site and gently lowered into the laboratory's Liquid-Argon Test Facility. This video documents that move, some taken with time-lapse camerad, and shows the process of getting the MicroBooNE detector to its new home.

  7. A freely-moving monkey treadmill model

    NASA Astrophysics Data System (ADS)

    Foster, Justin D.; Nuyujukian, Paul; Freifeld, Oren; Gao, Hua; Walker, Ross; Ryu, Stephen I.; Meng, Teresa H.; Murmann, Boris; Black, Michael J.; Shenoy, Krishna V.

    2014-08-01

    Objective. Motor neuroscience and brain-machine interface (BMI) design is based on examining how the brain controls voluntary movement, typically by recording neural activity and behavior from animal models. Recording technologies used with these animal models have traditionally limited the range of behaviors that can be studied, and thus the generality of science and engineering research. We aim to design a freely-moving animal model using neural and behavioral recording technologies that do not constrain movement. Approach. We have established a freely-moving rhesus monkey model employing technology that transmits neural activity from an intracortical array using a head-mounted device and records behavior through computer vision using markerless motion capture. We demonstrate the flexibility and utility of this new monkey model, including the first recordings from motor cortex while rhesus monkeys walk quadrupedally on a treadmill. Main results. Using this monkey model, we show that multi-unit threshold-crossing neural activity encodes the phase of walking and that the average firing rate of the threshold crossings covaries with the speed of individual steps. On a population level, we find that neural state-space trajectories of walking at different speeds have similar rotational dynamics in some dimensions that evolve at the step rate of walking, yet robustly separate by speed in other state-space dimensions. Significance. Freely-moving animal models may allow neuroscientists to examine a wider range of behaviors and can provide a flexible experimental paradigm for examining the neural mechanisms that underlie movement generation across behaviors and environments. For BMIs, freely-moving animal models have the potential to aid prosthetic design by examining how neural encoding changes with posture, environment and other real-world context changes. Understanding this new realm of behavior in more naturalistic settings is essential for overall progress of basic

  8. Slow-moving vehicles in Swedish traffic.

    PubMed

    Pinzke, S; Lundqvist, P

    2004-05-01

    The objective of this study was to reach a better understanding of accidents on Swedish roads involving slow-moving vehicles and to suggest ways of preventing such accidents. We analyzed accident data from a 5-year period (1992-1996) involving all types of farm vehicles as well as horses and horse-drawn vehicles. During each year of the period under investigation, slow-moving vehicles were involved in more than 250 traffic accidents on Swedish roads, and an average of 10 people were killed, 66 sustained serious injuries, and 192 sustained slight injuries. This was about 1.3% of all persons injured in traffic accidents in Sweden. The deaths and injuries mostly involved car drivers and passengers. Tractor drivers and unprotected road users (people walking or traveling by motorcycle, moped, or bicycle) also sustained serious injuries and deaths. Vehicles overtaking slow-moving vehicles from behind were the most common type of accident (30%), followed by turning accidents (27%), accidents at crossroads (26%), and with oncoming vehicles (17%). To strengthen the suggestions for improvement, a questionnaire was sent out to driving school teachers in Sweden. Subjects were asked about their experiences with farm vehicles on the roads and their suggestions for ways to increase traffic safety. Based on the accident data and the questionnaire responses, we developed several suggestions for reducing road accidents, including measures for making farm vehicles more visible, improvement of the training provided at driving schools, and information campaigns directed at drivers of farm vehicles and other road users. Further in-depth research is needed to analyze road accidents involving slow-moving vehicles and to test different intervention measures. PMID:15216651

  9. Culture as a Moving Symbolic Border.

    PubMed

    Simão, Lívia Mathias

    2016-03-01

    The aim of this paper is to propose the notion of culture as a symbolic moving border. Departing from both, Boesch's (1991) concept of culture as a symbolic field of action, and Herbst's (1995) co-genetic logic, I will discuss the dynamics of self-other relationships in terms of their potentiality as sources of movement in culture. A brief analysis of an empirical material is given in illustrative character of the ideas here exposed. PMID:26245862

  10. Predictive models for moving contact line flows

    NASA Technical Reports Server (NTRS)

    Rame, Enrique; Garoff, Stephen

    2003-01-01

    Modeling flows with moving contact lines poses the formidable challenge that the usual assumptions of Newtonian fluid and no-slip condition give rise to a well-known singularity. This singularity prevents one from satisfying the contact angle condition to compute the shape of the fluid-fluid interface, a crucial calculation without which design parameters such as the pressure drop needed to move an immiscible 2-fluid system through a solid matrix cannot be evaluated. Some progress has been made for low Capillary number spreading flows. Combining experimental measurements of fluid-fluid interfaces very near the moving contact line with an analytical expression for the interface shape, we can determine a parameter that forms a boundary condition for the macroscopic interface shape when Ca much les than l. This parameter, which plays the role of an "apparent" or macroscopic dynamic contact angle, is shown by the theory to depend on the system geometry through the macroscopic length scale. This theoretically established dependence on geometry allows this parameter to be "transferable" from the geometry of the measurement to any other geometry involving the same material system. Unfortunately this prediction of the theory cannot be tested on Earth.

  11. Photometer for tracking a moving light source

    NASA Technical Reports Server (NTRS)

    Strawa, Anthony W. (Inventor)

    2009-01-01

    A photometer that tracks a path of a moving light source with little or no motion of the photometer components. The system includes a non-moving, truncated paraboloid of revolution, having a paraboloid axis, a paraboloid axis, a small entrance aperture, a larger exit aperture and a light-reflecting inner surface, that receives and reflects light in a direction substantially parallel to the paraboloid axis. The system also includes a light processing filter to receive and process the redirected light, and to issue the processed, redirected light as processed light, and an array of light receiving elements, at least one of which receives and measures an associated intensity of a portion of the processed light. The system tracks a light source moving along a path and produces a corresponding curvilinear image of the light source path on the array of light receiving elements. Undesired light wavelengths from the light source may be removed by coating a selected portion of the reflecting inner surface or another light receiving surface with a coating that absorbs incident light in the undesired wavelength range.

  12. Moving source localization using seismic signal processing

    NASA Astrophysics Data System (ADS)

    Asgari, Shadnaz; Stafsudd, Jing Z.; Hudson, Ralph E.; Yao, Kung; Taciroglu, Ertugrul

    2015-01-01

    Accurate localization of a seismic source in a near-field scenario where the distances between sensors and the source are less than a few wavelengths of the generated signal has shown to be a challenging task. Conventional localization algorithms often prove to be ineffective, as near-field seismic signals exhibit characteristics different from the well-studied far-field signals. The current work is aimed at the employment of a seismic sensor array for the localization and tracking of a near-field wideband moving source. In this paper, the mathematical derivation of a novel DOA estimation algorithm-dubbed the Modified Kirlin Method-has been presented in details. The estimated DOAs are then combined using a least-squares optimization method for source localization. The performance of the proposed method has been evaluated in a field experiment to track a moving truck. We also compare the DOA estimation and source localization results of the proposed method with those of two other existing methods originally developed for localization of a stationary wideband source; Covariance Matrix Analysis and the Surface Wave Analysis. Our results indicate that both the Surface Wave Analysis and the Modified Kirlin Methods are effective in locating and tracking a moving truck.

  13. Efficient detection of small moving objects

    NASA Astrophysics Data System (ADS)

    Chu, Peter L.

    1989-07-01

    A signal processing problem encountered with many sensor systems having a wide field-of-view is detection of small, unresolved objects moving in a straight line amid stationary clutter. The wide field-of-view combined with the need to accurately pinpoint object positions imply that these sensors must have hundreds of thousands of samples in their output. To process this amount of data in a timely fashion, computationally efficient algorithms are a necessity. In this report, a computationally efficient set of algorithms is described for detecting satellites, meteorites, and other moving objects using data from an optical telescope charge-coupled device (CCD) focal plane in the MIT Lincoln Laboratory Demonstration Surveillance System (DSS). The trade-off of reduced detection sensitivity for lower computational cost in the algorithm is quantitatively discussed. Major techniques employed are: (1) sample normalization by temporal mean and standard deviation to suppress clutter; (2) maximum value projection to reduce the dimensionality of the data; (3) a two-stage matched filter detector which first nominates and then confirms signal candidates; and (4) two-dimensional binary velocity filtering. The techniques should have practical application to other wide field-of-view sensors where moving object detection is important.

  14. Moving wall, continuous flow electronphoresis apparatus

    NASA Technical Reports Server (NTRS)

    Rhodes, Percy H. (Inventor); Snyder, Robert S. (Inventor)

    1988-01-01

    This invention relates generally to electrophoresis devices and more particularly to a moving wall, continuous flow device in which an electrophoresis chamber is angularly positionable with respect to the direction of moving belt walls. A frame with an electrophoresis chamber is rotatably supported between two synchronously driven belt walls. This allows the chamber to be angularly positionable with respect to the direction of belt travel, which compensates for electroosmotic flow within the electrophoresis chamber. Injection of a buffer solution via an opening and a homogenous sample stream via another opening is performed at the end of a chamber, and collection of buffer and the fractionated species particles is done by a conventional collection array at an opposite end of the chamber. Belts are driven at a rate which exactly matches the flow of buffer and sample through the chamber, which entrains the buffer to behave as a rigid electrophoretic medium, eliminating flow distortions (Poiseuille effect). Additionally, belt material for each belt is stored at one end of the device and is taken up by drive wheels at an opposite end. The novelty of this invention particularly lies in the electrophoresis chamber being angularly positionable between two moving belt walls in order to compensate for electroosmotic flow. Additionally, new belt material is continuously exposed within the chamber, minimizing flow distortion due to contamination of the belt material by the sample.

  15. [Continuous ECG recording for freely moving patients].

    PubMed

    Shi, Bo; Liu, Shengyang; Chen, Jianfang; Zhang, Genxuan; Tsau, Young

    2013-04-01

    As more and more people are becoming aged in China and many of them tend to suffer from chronic cardiac problems, the long-term dynamic cardiac monitoring for freely moving patients becomes essential. A new design for continuous ECG recording on the freely moving patients at home and/or at work is proposed here. It is miniature in size, using digital technologies of the low gain amplifier, the high resolution analog to digital converter and the real-time digital filter that features > 100dB input signal dynamic range (ISDR), > 100dB common-mode rejection ratio (CMRR), and < 5microV (RMS) internal noise. The device works continuously more than 24 hours with a pair of AAA batteries, and is capable of storing the recorded data into a storage card. The preliminary tests showed that the P-QRS-T waveforms were captured and displayed smoothly in resting, walking, and activities, making the device useful in monitoring and analyzing for the patients on the move. PMID:23858751

  16. Radiative transfer in moving media : basic mathematical methods for radiative transfer in spherically symmetrical moving media

    NASA Astrophysics Data System (ADS)

    Sen, K. K., Wilson, S. J.

    The advancement of observational techniques over the years has led to the discovery of a large number of stars exhibiting complex spectral structures, thus necessitating the search for new techniques and methods to study radiative transfer in such stars with moving envelopes. This led to the introduction of the concept of "photon escape probability" and the wisdom of expressing the transfer equations in "comoving frames" (CMF). Radiative transfer problems in spherically moving media form a branch of mathematical physics which uses mathematics of a very distinctive kind. Radiative Transfer in Moving Media records the basic mathematical methodologies, both analytical and numerical, developed for solving radiation transfer problems in spherically symmetric moving media, in the consideration of macroscopic velocity fields only. Part I contains the basic notions of radiation-matter interaction in participating media and constructs the relevant transfer equations to be solved in the subsequent chapters. Part II considers the basic mathematical methods for solving the transfer problems in extensive moving atmospheres when it is observed in the lab frame. Part III introduces the analytical and numerical methods for solving radiative transfer problems in spherically symmetric moving atmospheres when expressed in the comoving frame. This book is addressed to graduate students and researchers in Astrophysics, in particular to those studying radiative transfer in stellar atmospheres.

  17. Ab Initio Studies of Stratospheric Ozone Depletion Chemistry

    NASA Technical Reports Server (NTRS)

    Lee, Timothy J.; Head-Gordon, Martin; Langhoff, Stephen R. (Technical Monitor)

    1995-01-01

    An overview of the current understanding of ozone depletion chemistry, particularly with regards the formation of the so-called Antarctic ozone hole, will be presented together with an outline as to how ab initio quantum chemistry can be used to further our understanding of stratospheric chemistry. The ability of modern state-of-the art ab initio quantum chemical techniques to characterize reliably the gas-phase molecular structure, vibrational spectrum, electronic spectrum, and thermal stability of fluorine, chlorine, bromine and nitrogen oxide species will be demonstrated by presentation of some example studies. The ab initio results will be shown to be in excellent agreement with the available experimental data, and where the experimental data are either not known or are inconclusive, the theoretical results are shown to fill in the gaps and to resolve experimental controversies. In addition, ab initio studies in which the electronic spectra and the characterization of excited electronic states of halogen oxide species will also be presented. Again where available, the ab initio results are compared to experimental observations, and are used to aid in the interpretation of experimental studies.

  18. THERMODYNAMICS OF MATERIALS: FROM AB INITIO TO PHENOMENOLOGY

    SciTech Connect

    Turchi, P A

    2004-09-24

    Quantum mechanical-based (or ab initio) methods are used to predict the stability properties of materials although their application is limited to relatively simple systems in terms of structures and number of alloy components. However thermodynamics of complex multi-component alloys requires a more versatile approach afforded within the CALPHAD formalism. Despite its success, the lack of experimental data very often prevents the design of robust thermodynamic databases. After a brief survey of ab initio methodologies and CALPHAD, it will be shown how ab initio electronic structure methods can supplement in two ways CALPHAD for subsequent applications. The first one is rather immediate and concerns the direct input of ab initio energetics in CALPHAD databases. The other way, more involved, is the assessment of ab initio thermodynamics '{acute a} la CALPHAD'. It will be shown how these results can be used within CALPHAD to predict the equilibrium properties of multi-component alloys. Finally, comments will be made on challenges and future prospects.

  19. Does poor health predict moving, move quality, and desire to move?: A study examining neighborhood selection in US adolescents and adults

    PubMed Central

    Dunn, Erin C.; Winning, Ashley; Zaika, Natalya; Subramanian, S.V.

    2015-01-01

    Background To date, very little research has considered the role of health on shaping characteristics of the neighborhood, including mobility patterns. We explored whether individual health status is one of the characteristics that shape and constrain where individuals live. Methods Using data from the National Longitudinal Study of Adolescent Health, we examined whether 16 health indicators (e.g., health behaviors, symptoms, overall status) predicted moving, move quality, and desire to move. Results 3.8% of adolescents (n=490) reported a move in the past year. In the unadjusted models, 10 health indicators were associated with moving; the magnitude of association for these health indicators was similar to socio-demographic characteristics. Seven of these health-moving associations persisted after adjusting for covariates. Health indicators were also associated with moving quality, with a greater number of past year health problems in the child being associated with moving to lower income neighborhood and parent disability or poor health being associated with moving to a higher income neighborhood. Almost every poor health status indicator was associated with a greater desire to move, even after adjusting for covariates. Conclusion Findings suggest health status influences moving. Prior health status must therefore be considered when interpreting results from neighborhood effects studies. PMID:25282124

  20. The Over-Expression of Two Transcription Factors, ABS5/bHLH30 and ABS7/MYB101, Leads to Upwardly Curly Leaves

    PubMed Central

    Wang, Rui; Wu, Haicui; Liang, Shuang; Shao, Jingxia; Qi, Yafei; An, Lijun; Yu, Fei

    2014-01-01

    Proper leaf development is essential for plant growth and development, and leaf morphogenesis is under the control of intricate networks of genetic and environmental cues. We are interested in dissecting these regulatory circuits genetically and report here the isolation of two Arabidopsis dominant mutants, abnormal shoot5-1D (abs5-1D) and abs7-1D identified through activation tagging screens. Both abs5-1D and abs7-1D display an intriguing upwardly curly leaf phenotype. Molecular cloning showed that the elevated expression of a bHLH transcription factor ABS5/T5L1/bHLH30 or a MYB transcription factor ABS7/MYB101 is the cause for the abnormal leaf phenotypes found in abs5-1D or abs7-1D, respectively. Protoplast transient expression assays confirmed that both ABS5/T5L1 and ABS7/MYB101 are targeted to the nucleus. Interestingly, the expression domains of auxin response reporter DR5::GUS were abnormal in leaves of abs5-1D and ABS5/T5L1 over-expression lines. Moreover, cotyledon venation analysis showed that more areoles and free-ending veins are formed in abs5-1D. We found that the epidermis-specific expressions of ABS5/T5L1 or ABS7/MYB101 driven by the Arabidopsis Meristem Layer 1 promoter (PAtML1) were sufficient to recapitulate the curly leaf phenotype of abs5-1D or abs7-1D. In addition, PAtML1::ABS5 lines exhibited similar changes in DR5::GUS expression patterns as those found in 35S-driven ABS5/T5L1 over-expression lines. Our work demonstrated that enhanced expressions of two transcription factors, ABS5/T5L1 and ABS7/MYB101, are able to alter leaf lamina development and reinforce the notion that leaf epidermis plays critical roles in regulating plant organ morphogenesis. PMID:25268707

  1. Condition-dependent migratory behaviour of endangered Atlantic salmon smolts moving through an inland sea.

    PubMed

    Crossin, Glenn T; Hatcher, Bruce G; Denny, Shelley; Whoriskey, Kim; Orr, Michael; Penney, Alicia; Whoriskey, Frederick G

    2016-01-01

    The Bras d'Or Lake watershed of Cape Breton Island, Nova Scotia, Canada is a unique inland sea ecosystem, UNESCO Biosphere Reserve and home to a group of regionally distinct Atlantic salmon (Salmo salar) populations. Recent population decreases in this region have raised concern about their long-term persistence. We used acoustic telemetry to track the migrations of juvenile salmon (smolts) from the Middle River into the Bras d'Or Lake and, subsequently, into the Atlantic Ocean. Roughly half of the tagged smolts transited the Bras d'Or Lakes to the Atlantic Ocean, using a migration route that took them through the Gulf of St Lawrence's northern exit at the Strait of Belle Isle (∼650 km from the home river) towards feeding areas in the Labrador Sea and Greenland. However, a significant fraction spent >70 days in the Lakes, suggesting that this population has an alternative resident form, in which smolts limit their migrations within the Bras d'Or. Smolts in good relative condition (as determined from length-to-mass relationships) tended to be residents, whereas fish in poorer condition were ocean migrants. We also found a covarying effect of river temperature that helped to predict residence vs. ocean migration. We discuss these results relative to their bioenergetic implications and provide suggestions for future studies aimed at the conservation of declining salmon populations in Canada. PMID:27293765

  2. Ab initio simulation of transport phenomena in rarefied gases.

    PubMed

    Sharipov, Felix; Strapasson, José L

    2012-09-01

    Ab initio potentials are implemented into the direct simulation Monte Carlo (DSMC) method. Such an implementation allows us to model transport phenomena in rarefied gases without any fitting parameter of intermolecular collisions usually extracted from experimental data. Applying the method proposed by Sharipov and Strapasson [Phys. Fluids 24, 011703 (2012)], the use of ab initio potentials in the DSMC requires the same computational efforts as the widely used potentials such as hard spheres, variable hard sphere, variable soft spheres, etc. At the same time, the ab initio potentials provide more reliable results than any other one. As an example, the transport coefficients of a binary mixture He-Ar, viz., viscosity, thermal conductivity, and thermal diffusion factor, have been calculated for several values of the mole fraction. PMID:23030889

  3. Birefringence in time-dependent moving media

    NASA Astrophysics Data System (ADS)

    Lin, Shirong; Zhang, Ruoyang; Zhai, Yanwang; Wei, Jianye; Zhao, Qing

    2016-08-01

    Electromagnetic wave propagation in one- and two-dimensional time-dependent moving media is investigated in this paper. We identify another origin of linear birefringence caused by the component of the flow perpendicular to the wave vector. Previously, birefringence is induced by applying external electric and magnetic fields to non-crystalline material. Here it is shown that the time-varying velocity field also contributes to such a phenomenon. Our results indicate that the parallel component, time-dependent or not, will not yield birefringence. Furthermore, the time-dependent flow also results in a frequency shift. One-dimensional simulation is conducted to demonstrate these effects.

  4. An improved moving average technical trading rule

    NASA Astrophysics Data System (ADS)

    Papailias, Fotis; Thomakos, Dimitrios D.

    2015-06-01

    This paper proposes a modified version of the widely used price and moving average cross-over trading strategies. The suggested approach (presented in its 'long only' version) is a combination of cross-over 'buy' signals and a dynamic threshold value which acts as a dynamic trailing stop. The trading behaviour and performance from this modified strategy are different from the standard approach with results showing that, on average, the proposed modification increases the cumulative return and the Sharpe ratio of the investor while exhibiting smaller maximum drawdown and smaller drawdown duration than the standard strategy.

  5. Shadowfax: Moving mesh hydrodynamical integration code

    NASA Astrophysics Data System (ADS)

    Vandenbroucke, Bert

    2016-05-01

    Shadowfax simulates galaxy evolution. Written in object-oriented modular C++, it evolves a mixture of gas, subject to the laws of hydrodynamics and gravity, and any collisionless fluid only subject to gravity, such as cold dark matter or stars. For the hydrodynamical integration, it makes use of a (co-) moving Lagrangian mesh. The code has a 2D and 3D version, contains utility programs to generate initial conditions and visualize simulation snapshots, and its input/output is compatible with a number of other simulation codes, e.g. Gadget2 (ascl:0003.001) and GIZMO (ascl:1410.003).

  6. Computing Proton Dose to Irregularly Moving Targets

    PubMed Central

    Phillips, Justin; Gueorguiev, Gueorgui; Shackleford, James A.; Grassberger, Clemens; Dowdell, Stephen; Paganetti, Harald; Sharp, Gregory C.

    2014-01-01

    Purpose While four-dimensional computed tomography (4DCT) and deformable registration can be used to assess the dose delivered to regularly moving targets, there are few methods available for irregularly moving targets. 4DCT captures an idealized waveform, but human respiration during treatment is characterized by gradual baseline shifts and other deviations from a periodic signal. This paper describes a method for computing the dose delivered to irregularly moving targets based on 1D or 3D waveforms captured at the time of delivery. Methods The procedure uses CT or 4DCT images for dose calculation, and 1D or 3D respiratory waveforms of the target position at time of delivery. Dose volumes are converted from their Cartesian geometry into a beam-specific radiological depth space, parameterized in 2D by the beam aperture, and longitudinally by the radiological depth. In this new frame of reference, the proton doses are translated according to the motion found in the 1D or 3D trajectory. These translated dose volumes are weighted and summed, then transformed back into Cartesian space, yielding an estimate of the dose that includes the effect of the measured breathing motion. The method was validated using a synthetic lung phantom and a single representative patient CT. Simulated 4DCT was generated for the phantom with 2 cm peak-to-peak motion. Results A passively-scattered proton treatment plan was generated using 6 mm and 5 mm smearing for the phantom and patient plans, respectively. The method was tested without motion, and with two simulated breathing signals: a 2 cm amplitude sinusoid, and a 2 cm amplitude sinusoid with 3 cm linear drift in the phantom. The tumor positions were equally weighted for the patient calculation. Motion-corrected dose was computed based on the mid-ventilation CT image in the phantom and the peak exhale position in the patient. Gamma evaluation was 97.8% without motion, 95.7% for 2 cm sinusoidal motion, and 95.7% with 3 cm drift in the

  7. Russian Soyuz Moves to Launch Pad

    NASA Technical Reports Server (NTRS)

    2000-01-01

    The Soyuz TM-31 launch vehicle, which carried the first resident crew to the International Space Station, moves toward the launch pad at the Baikonur complex in Kazakhstan. The Russian Soyuz launch vehicle is an expendable spacecraft that evolved out of the original Class A (Sputnik). From the early 1960' until today, the Soyuz launch vehicle has been the backbone of Russia's marned and unmanned space launch fleet. Today, the Soyuz launch vehicle is marketed internationally by a joint Russian/French consortium called STARSEM. As of August 2001, there have been ten Soyuz missions under the STARSEM banner.

  8. Future perspectives: Moving towards NCL treatments.

    PubMed

    Cotman, Susan L; Mole, Sara E; Kohan, Romina

    2015-10-01

    Clinicians, basic researchers, representatives from pharma and families from around the world met in Cordoba, Argentina in October, 2014 to discuss recent research progress at the 14th International Congress on Neuronal Ceroid Lipofuscinoses (NCLs; Batten disease), a group of clinically overlapping fatal, inherited lysosomal disorders with primarily neurodegenerative symptoms. This brief review article will provide perspectives on the anticipated future directions of NCL basic and clinical research as we move towards improved diagnosis, care and treatment of NCL patients. This article is part of a Special Issue entitled: Current Research on the Neuronal Ceroid Lipofuscinoses (Batten Disease). PMID:25857620

  9. Moving finite elements in 2-D

    NASA Technical Reports Server (NTRS)

    Gelinas, R. J.; Doss, S. K.; Vajk, J. P.; Djomehri, J.; Miller, K.

    1983-01-01

    The mathematical background regarding the moving finite element (MFE) method of Miller and Miller (1981) is discussed, taking into account a general system of partial differential equations (PDE) and the amenability of the MFE method in two dimensions to code modularization and to semiautomatic user-construction of numerous PDE systems for both Dirichlet and zero-Neumann boundary conditions. A description of test problem results is presented, giving attention to aspects of single square wave propagation, and a solution of the heat equation.

  10. Computing proton dose to irregularly moving targets

    NASA Astrophysics Data System (ADS)

    Phillips, Justin; Gueorguiev, Gueorgui; Shackleford, James A.; Grassberger, Clemens; Dowdell, Stephen; Paganetti, Harald; Sharp, Gregory C.

    2014-08-01

    Purpose: While four-dimensional computed tomography (4DCT) and deformable registration can be used to assess the dose delivered to regularly moving targets, there are few methods available for irregularly moving targets. 4DCT captures an idealized waveform, but human respiration during treatment is characterized by gradual baseline shifts and other deviations from a periodic signal. This paper describes a method for computing the dose delivered to irregularly moving targets based on 1D or 3D waveforms captured at the time of delivery. Methods: The procedure uses CT or 4DCT images for dose calculation, and 1D or 3D respiratory waveforms of the target position at time of delivery. Dose volumes are converted from their Cartesian geometry into a beam-specific radiological depth space, parameterized in 2D by the beam aperture, and longitudinally by the radiological depth. In this new frame of reference, the proton doses are translated according to the motion found in the 1D or 3D trajectory. These translated dose volumes are weighted and summed, then transformed back into Cartesian space, yielding an estimate of the dose that includes the effect of the measured breathing motion. The method was validated using a synthetic lung phantom and a single representative patient CT. Simulated 4DCT was generated for the phantom with 2 cm peak-to-peak motion. Results: A passively-scattered proton treatment plan was generated using 6 mm and 5 mm smearing for the phantom and patient plans, respectively. The method was tested without motion, and with two simulated breathing signals: a 2 cm amplitude sinusoid, and a 2 cm amplitude sinusoid with 3 cm linear drift in the phantom. The tumor positions were equally weighted for the patient calculation. Motion-corrected dose was computed based on the mid-ventilation CT image in the phantom and the peak exhale position in the patient. Gamma evaluation was 97.8% without motion, 95.7% for 2 cm sinusoidal motion, 95.7% with 3 cm drift in the

  11. Compressor Has No Moving Macroscopic Parts

    NASA Technical Reports Server (NTRS)

    Gasser, Max

    1995-01-01

    Compressor containing no moving macroscopic parts functions by alternating piston and valve actions of successive beds of magnetic particles. Fabricated easily because no need for precisely fitting parts rotating or sliding on each other. Also no need for lubricant fluid contaminating fluid to be compressed. Compressor operates continuously, eliminating troublesome on/off cycling of other compressors, and decreasing consumption of energy. Phased cells push fluid from bottom to top, adding increments of pressure. Each cell contains magnetic powder particles loose when electromagnet coil deenergized, but tightly packed when coil energized.

  12. Fast bilateral filtering using recursive moving sum

    NASA Astrophysics Data System (ADS)

    Igarashi, Masaki; Ikebe, Masayuki; Shimoyama, Sohsuke; Motohisa, Junichi

    We propose a constant-time algorithm for a bilateral filter. Bilateral filter can be converted into the operation of three-dimensional (3D) convolution. By using recursive moving sum, we can reduce the number of calculations needed to construct a pseudo-Gaussian filter. Applying one-dimensional Gaussian filter to the 3D convolution, we achieved a constant-time bilateral filter. We used a 3-GHz CPU without SIMD instructions, or multi-thread operations. We confirmed our proposed bilateral filter to be processed in constant time. In practical conditions, high PSNR values over 40 dB are obtained.

  13. Tests to Help Plan Opportunity Moves

    NASA Technical Reports Server (NTRS)

    2005-01-01

    Rover engineers check how a test rover moves in material chosen to simulate some difficult Mars driving conditions. The scene is inside the In-Situ Instrument Laboratory at NASA's Jet Propulsion Laboratory, Pasadena, Calif. These tests in early May 2005 were designed to help plan the best way for the rover Opportunity to drive off of a soft-sand dune that the rover dug itself into the previous week. The mixture of sandy and powdery material brought in for these specific tests matched the way the soil underneath Opportunity caked onto wheels, filling the spaces between the cleats on the wheels.

  14. Computational cameras for moving iris recognition

    NASA Astrophysics Data System (ADS)

    McCloskey, Scott; Venkatesha, Sharath

    2015-05-01

    Iris-based biometric identification is increasingly used for facility access and other security applications. Like all methods that exploit visual information, however, iris systems are limited by the quality of captured images. Optical defocus due to a small depth of field (DOF) is one such challenge, as is the acquisition of sharply-focused iris images from subjects in motion. This manuscript describes the application of computational motion-deblurring cameras to the problem of moving iris capture, from the underlying theory to system considerations and performance data.

  15. Light scattering from a moving atom.

    PubMed

    Guo, Wei

    2012-12-01

    In this work, scattering of an incident electric field from a moving atom is reexamined classically in two steps: the time-dependent current density created by the field inside the atom is first calculated under the electric-dipole approximation, and is then used to calculate the field scattered from the atom. Unlike the conventional frame-hopping method, the present method does not need to treat the Doppler effect as an effect separated from the scattering process, and it derives instead of simply uses the Doppler effect. PMID:23455906

  16. A Trajectory and Orientation Reconstruction Method for Moving Objects Based on a Moving Monocular Camera

    PubMed Central

    Zhou, Jian; Shang, Yang; Zhang, Xiaohu; Yu, Wenxian

    2015-01-01

    We propose a monocular trajectory intersection method to solve the problem that a monocular moving camera cannot be used for three-dimensional reconstruction of a moving object point. The necessary and sufficient condition of when this method has the unique solution is provided. An extended application of the method is to not only achieve the reconstruction of the 3D trajectory, but also to capture the orientation of the moving object, which would not be obtained by PnP problem methods due to lack of features. It is a breakthrough improvement that develops the intersection measurement from the traditional “point intersection” to “trajectory intersection” in videometrics. The trajectory of the object point can be obtained by using only linear equations without any initial value or iteration; the orientation of the object with poor conditions can also be calculated. The required condition for the existence of definite solution of this method is derived from equivalence relations of the orders of the moving trajectory equations of the object, which specifies the applicable conditions of the method. Simulation and experimental results show that it not only applies to objects moving along a straight line, or a conic and another simple trajectory, but also provides good result for more complicated trajectories, making it widely applicable. PMID:25760053

  17. Stimulation of UvrD helicase by UvrAB.

    PubMed

    Atkinson, John; Guy, Colin P; Cadman, Chris J; Moolenaar, Geri F; Goosen, Nora; McGlynn, Peter

    2009-04-01

    Helicases play critical roles in all aspects of nucleic acid metabolism by catalyzing the remodeling of DNA and RNA structures. UvrD is an abundant helicase in Escherichia coli with well characterized functions in mismatch and nucleotide excision repair and a possible role in displacement of proteins such as RecA from single-stranded DNA. The mismatch repair protein MutL is known to stimulate UvrD. Here we show that the nucleotide excision repair proteins UvrA and UvrB can together stimulate UvrD-catalyzed unwinding of a range of DNA substrates containing strand discontinuities, including forked DNA substrates. The stimulation is specific for UvrD, as UvrAB failed to stimulate Rep helicase, a UvrD homologue. Moreover, although UvrAB can promote limited strand displacement, stimulation of UvrD did not require the strand displacement function of UvrAB. We conclude that UvrAB, like MutL, modulate UvrD helicase activity. This stimulation likely plays a role in DNA strand and protein displacement by UvrD in nucleotide excision repair. Promotion of UvrD-catalyzed unwinding of nicked duplexes by UvrAB may also explain the need for UvrAB and UvrD in Okazaki fragment processing in cells lacking DNA polymerase I. More generally, these data support the idea that helicase activity is regulated in vivo, with helicases acting as part of multisubunit complexes rather than in isolation. PMID:19208629

  18. Ab initio computations of photodissociation products of CFC alternatives

    SciTech Connect

    Tai, S.; Illinger, K.H.; Kenny, J.E.

    1995-12-31

    Ab initio computations, have already been used to examine the energetics of the photodissociation of stratospheric chlorofluorocarbons. Our awn research has investigated the ab initio computation of vibrational frequencies and infrared intensities of CF{sub 3}CH{sub 2}F, CF{sub 3}CF{sub 2}H, and CF{sub 3}CH{sub 3}; continuing research will attempt to expand these computations to the energetics of the photodissociation of these molecules, since sane of the most common types of chlorofluorocarbon substitutes are hydrofluoroethanes.

  19. An ABS control logic based on wheel force measurement

    NASA Astrophysics Data System (ADS)

    Capra, D.; Galvagno, E.; Ondrak, V.; van Leeuwen, B.; Vigliani, A.

    2012-12-01

    The paper presents an anti-lock braking system (ABS) control logic based on the measurement of the longitudinal forces at the hub bearings. The availability of force information allows to design a logic that does not rely on the estimation of the tyre-road friction coefficient, since it continuously tries to exploit the maximum longitudinal tyre force. The logic is designed by means of computer simulation and then tested on a specific hardware in the loop test bench: the experimental results confirm that measured wheel force can lead to a significant improvement of the ABS performances in terms of stopping distance also in the presence of road with variable friction coefficient.

  20. Ab Initio Structure Analysis Using Laboratory Powder Diffraction Data

    NASA Astrophysics Data System (ADS)

    Sasaki, Akito

    Today, laboratory X-ray diffractometers are seeing increasingly wide use in the ab initio crystal structure analysis of organic powder samples. This is because optics and optical devices have been improved, making it possible to obtain precise integrated intensities of reflections in high 2-theta ranges. Another reason is that one can use direct-space methods, which do not require “high-resolution diffraction data”, much more easily than before. Described here are some key points to remember when performig ab initio crystal structure analysis using powder diffraction data from organic compounds.

  1. Ice Particle Impacts on a Moving Wedge

    NASA Technical Reports Server (NTRS)

    Vargas, Mario; Struk, Peter M.; Kreeger, Richard E.; Palacios, Jose; Lyer, Kaushik A.; Gold, Robert E.

    2014-01-01

    This work presents the results of an experimental study of ice particle impacts on a moving wedge. The experiment was conducted in the Adverse Environment Rotor Test Stand (AERTS) facility located at Penn State University. The wedge was placed at the tip of a rotating blade. Ice particles shot from a pressure gun intercepted the moving wedge and impacted it at a location along its circular path. The upward velocity of the ice particles varied from 7 to 12 meters per second. Wedge velocities were varied from 0 to 120 meters per second. Wedge angles tested were 0, 30, 45, and 60. High speed imaging combined with backlighting captured the impact allowing observation of the effect of velocity and wedge angle on the impact and the post-impact fragment behavior. It was found that the pressure gun and the rotating wedge could be synchronized to consistently obtain ice particle impacts on the target wedge. It was observed that the number of fragments increase with the normal component of the impact velocity. Particle fragments ejected immediately after impact showed velocities higher than the impact velocity. The results followed the major qualitative features observed by other researchers for hailstone impacts, even though the reduced scale size of the particles used in the present experiment as compared to hailstones was 4:1.

  2. Ice Particle Impacts on a Moving Wedge

    NASA Technical Reports Server (NTRS)

    Vargas, Mario; Struk, Peter M.; Kreeger, Richard E.; Palacios, Jose; Iyer, Kaushik A.; Gold, Robert E.

    2014-01-01

    This work presents the results of an experimental study of ice particle impacts on a moving wedge. The experiment was conducted in the Adverse Environment Rotor Test Stand (AERTS) facility located at Penn State University. The wedge was placed at the tip of a rotating blade. Ice particles shot from a pressure gun intercepted the moving wedge and impacted it at a location along its circular path. The upward velocity of the ice particles varied from 7 to 12 meters per second. Wedge velocities were varied from 0 to 120 meters per second. Wedge angles tested were 0 deg, 30 deg, 45 deg, and 60 deg. High speed imaging combined with backlighting captured the impact allowing observation of the effect of velocity and wedge angle on the impact and the post-impact fragment behavior. It was found that the pressure gun and the rotating wedge could be synchronized to consistently obtain ice particle impacts on the target wedge. It was observed that the number of fragments increase with the normal component of the impact velocity. Particle fragments ejected immediately after impact showed velocities higher than the impact velocity. The results followed the major qualitative features observed by other researchers for hailstone impacts, even though the reduced scale size of the particles used in the present experiment as compared to hailstones was 4:1.

  3. Standleg Moving Granular Bed Filter development program

    SciTech Connect

    Newby, R.A.; Yang, W.C.; Smeltzer, E.E.

    1992-11-01

    The design, fabrication, and installation of the cold flow test facility has been completed. The SMGBF test facility shown in Figure 2 consists of a solids feed hopper, a transparent test vessel, a screw conveyor, a 55-gal drum for solids storage, a dust feeder, a baghouse filter, and the associated instrumentation for flow and pressure control and measurement. The standleg is 11-in ID by 3-ft long, and also transparent to facilitate observation. The crushed acrylic particles of characteristics shown in Table 1 are used as the bed media. The bed particles were selected, by maintaining the particle size while reducing the particle density, to simulate the minimum fluidization velocity expected under high-temperature, high-pressure conditions. By maintaining the particle size, the bed effectively simulates the bed packing and voidage in the moving bed which is directly related to the efficiency of particulate removal and pressure drop characteristics. The test facility performed as designed and no particular difficulties were encountered. The baseline data on pressure profiles across the stationary and the moving granular beds were obtained for gas face velocities up to 6 ft/s, higher than the minimum fluidization velocity of the bed material (5 ft/s), and no visible fluidization was observed at the base of the standleg. This confirms the operational feasibility of the compact SMGBF design.

  4. Standleg Moving Granular Bed Filter development program

    SciTech Connect

    Newby, R.A.; Yang, W.C.; Smeltzer, E.E.

    1992-01-01

    The design, fabrication, and installation of the cold flow test facility has been completed. The SMGBF test facility shown in Figure 2 consists of a solids feed hopper, a transparent test vessel, a screw conveyor, a 55-gal drum for solids storage, a dust feeder, a baghouse filter, and the associated instrumentation for flow and pressure control and measurement. The standleg is 11-in ID by 3-ft long, and also transparent to facilitate observation. The crushed acrylic particles of characteristics shown in Table 1 are used as the bed media. The bed particles were selected, by maintaining the particle size while reducing the particle density, to simulate the minimum fluidization velocity expected under high-temperature, high-pressure conditions. By maintaining the particle size, the bed effectively simulates the bed packing and voidage in the moving bed which is directly related to the efficiency of particulate removal and pressure drop characteristics. The test facility performed as designed and no particular difficulties were encountered. The baseline data on pressure profiles across the stationary and the moving granular beds were obtained for gas face velocities up to 6 ft/s, higher than the minimum fluidization velocity of the bed material (5 ft/s), and no visible fluidization was observed at the base of the standleg. This confirms the operational feasibility of the compact SMGBF design.

  5. Focusing on moving targets through scattering samples

    PubMed Central

    Zhou, Edward Haojiang; Ruan, Haowen; Yang, Changhuei; Judkewitz, Benjamin

    2014-01-01

    Focusing light through scattering media has been a longstanding goal of biomedical optics. While wavefront shaping and optical time-reversal techniques can in principle be used to focus light across scattering media, achieving this within a scattering medium with a noninvasive and efficient reference beacon, or guide star, remains an important challenge. Here, we show optical time-reversal focusing using a new technique termed Time Reversal by Analysis of Changing wavefronts from Kinetic targets (TRACK). By taking the difference between time-varying scattering fields caused by a moving object and applying optical time reversal, light can be focused back to the location previously occupied by the object. We demonstrate this approach with discretely moved objects as well as with particles in an aqueous flow, and obtain a focal peak-to-background strength of 204 in our demonstration experiments. We further demonstrate that the generated focus can be used to noninvasively count particles in a flow-cytometry configuration—even when the particles are hidden behind a strong diffuser. By achieving optical time reversal and focusing noninvasively without any external guide stars, using just the intrinsic characteristics of the sample, this work paves the way to a range of scattering media imaging applications, including underwater and atmospheric focusing as well as noninvasive in vivo flow cytometry. PMID:25621302

  6. Preparation for Moving a Rock on Mars

    NASA Technical Reports Server (NTRS)

    2008-01-01

    The robotic arm on NASA's Phoenix Mars Lander enlarged a trench beside a rock called 'Headless' during the mission's 115th Martian day (Sept. 20, 2008) in preparation for sliding the rock into the trench. The lander's Surface Stereo Imager took this image later that afternoon, showing the enlarged trench and the rock.

    The robotic arm successfully moved the rock two days later.

    The Phoenix science team sought to move the rock in order to study the soil and the depth to subsurface ice underneath where the rock had been.

    Headless is about the size and shape of a VHS videotape. The trench, called 'Neverland,' was excavated to about 3 centimeters (1.2 inches) deep near the rock. The ground surface between the rock and the lip of the trench slopes downward about 3 degrees toward the trench.

    This image was taken at about 4:35 p.m., local solar time on Mars. The view is to the north northeast of the lander.

    The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by JPL, Pasadena, Calif. Spacecraft development was by Lockheed Martin Space Systems, Denver.

  7. Deciphering Interactions in Moving Animal Groups

    PubMed Central

    Gautrais, Jacques; Ginelli, Francesco; Fournier, Richard; Blanco, Stéphane; Soria, Marc; Chaté, Hugues; Theraulaz, Guy

    2012-01-01

    Collective motion phenomena in large groups of social organisms have long fascinated the observer, especially in cases, such as bird flocks or fish schools, where large-scale highly coordinated actions emerge in the absence of obvious leaders. However, the mechanisms involved in this self-organized behavior are still poorly understood, because the individual-level interactions underlying them remain elusive. Here, we demonstrate the power of a bottom-up methodology to build models for animal group motion from data gathered at the individual scale. Using video tracks of fish shoal in a tank, we show how a careful, incremental analysis at the local scale allows for the determination of the stimulus/response function governing an individual's moving decisions. We find in particular that both positional and orientational effects are present, act upon the fish turning speed, and depend on the swimming speed, yielding a novel schooling model whose parameters are all estimated from data. Our approach also leads to identify a density-dependent effect that results in a behavioral change for the largest groups considered. This suggests that, in confined environment, the behavioral state of fish and their reaction patterns change with group size. We debate the applicability, beyond the particular case studied here, of this novel framework for deciphering interactions in moving animal groups. PMID:23028277

  8. Investigation of Moving Belt Radiator Technology Issues

    NASA Technical Reports Server (NTRS)

    Teagan, W. Peter; Aguilar, Jerry L.

    1994-01-01

    The development of an advanced spacecraft radiator technology is reported. The moving belt radiator is a thermal radiator concept with the promise of lower specific mass (per kW rejected) than that afforded by existing technologies. The results of a parametric study to estimate radiator mass for future space power systems is presented. It is shown that this technology can be scaled up to 200 MW for higher rejection temperatures. Several aspects of the design concept are discussed, including the dynamics of a large rotating belt in microgravity. The results of a computer code developed to model the belt dynamics are presented. A series of one-g experiments to investigate the dynamics of small belts is described. A comprehensive test program to investigate belt dynamics in microgravity aboard the NASA KC-135 aircraft is discussed. It was found that the desired circular shape can readily be achieved in microgravity. It is also shown that a rotating belt is stable when subjected to simulated attitude control maneuvers. Heat exchanger design is also investigated. Several sealing concepts were examined experimentally, and are discussed. Overall heat transfer coefficients to the rotating belt are presented. Material properties for various belt materials, including screen meshes, are also presented. The results presented in this report indicate that the moving belt radiator concept is technically feasible.

  9. Hybrid Heat Capacity - Moving Slab Laser Concept

    SciTech Connect

    Stappaerts, E A

    2002-04-01

    A hybrid configuration of a heat capacity laser (HCL) and a moving slab laser (MSL) has been studied. Multiple volumes of solid-state laser material are sequentially diode-pumped and their energy extracted. When a volume reaches a maximum temperature after a ''sub-magazine depth'', it is moved out of the pumping region into a cooling region, and a new volume is introduced. The total magazine depth equals the submagazine depth times the number of volumes. The design parameters are chosen to provide high duty factor operation, resulting in effective use of the diode arrays. The concept significantly reduces diode array cost over conventional heat capacity lasers, and it is considered enabling for many potential applications. A conceptual design study of the hybrid configuration has been carried out. Three concepts were evaluated using CAD tools. The concepts are described and their relative merits discussed. Because of reduced disk size and diode cost, the hybrid concept may allow scaling to average powers on the order of 0.5 MW/module.

  10. Mapping brain function in freely moving subjects

    PubMed Central

    Holschneider, Daniel P.; Maarek, Jean-Michel I.

    2014-01-01

    Expression of many fundamental mammalian behaviors such as, for example, aggression, mating, foraging or social behaviors, depend on locomotor activity. A central dilemma in the functional neuroimaging of these behaviors has been the fact that conventional neuroimaging techniques generally rely on immobilization of the subject, which extinguishes all but the simplest activity. Ideally, imaging could occur in freely moving subjects, while presenting minimal interference with the subject’s natural behavior. Here we provide an overview of several approaches that have been undertaken in the past to achieve this aim in both tethered and freely moving animals, as well as in nonrestrained human subjects. Applications of specific radiotracers to single photon emission computed tomography and positron emission tomography are discussed in which brain activation is imaged after completion of the behavioral task and capture of the tracer. Potential applications to clinical neuropsychiatry are discussed, as well as challenges inherent to constraint-free functional neuroimaging. Future applications of these methods promise to increase our understanding of the neural circuits underlying mammalian behavior in health and disease. PMID:15465134

  11. A Moving Grid Capability for NPARC

    NASA Technical Reports Server (NTRS)

    Slater, John W.

    1998-01-01

    Version 3.1 of the NPARC computational fluid dynamics flow solver introduces a capability to solve unsteady flow on moving multi-block, structured grids with nominally second-order time accuracy. The grid motion is due to segments of the boundary grid that translate and rotate in a rigid-body manner or deform. The grid is regenerated at each time step to accommodate the boundary grid motion. The flow equations and computational models sense the moving grid through the grid velocities, which are computed from a time-difference of the grids at two consecutive time levels. For three-dimensional flow domains, it is assumed that the grid retains a planar character with respect to one coordinate. The application and accuracy of NPARC v3.1 is demonstrated for flow about a flying wedge, rotating flap, a collapsing bump in a duct, and the upstart / restart flow in a variable-geometry inlet. The results compare well with analytic and experimental results.

  12. Acoustic field in unsteady moving media

    NASA Technical Reports Server (NTRS)

    Bauer, F.; Maestrello, L.; Ting, L.

    1995-01-01

    In the interaction of an acoustic field with a moving airframe the authors encounter a canonical initial value problem for an acoustic field induced by an unsteady source distribution, q(t,x) with q equivalent to 0 for t less than or equal to 0, in a medium moving with a uniform unsteady velocity U(t)i in the coordinate system x fixed on the airframe. Signals issued from a source point S in the domain of dependence D of an observation point P at time t will arrive at point P more than once corresponding to different retarded times, Tau in the interval (0, t). The number of arrivals is called the multiplicity of the point S. The multiplicity equals 1 if the velocity U remains subsonic and can be greater when U becomes supersonic. For an unsteady uniform flow U(t)i, rules are formulated for defining the smallest number of I subdomains V(sub i) of D with the union of V(sub i) equal to D. Each subdomain has multiplicity 1 and a formula for the corresponding retarded time. The number of subdomains V(sub i) with nonempty intersection is the multiplicity m of the intersection. The multiplicity is at most I. Examples demonstrating these rules are presented for media at accelerating and/or decelerating supersonic speed.

  13. Governing synthetic biology in the light of the Access and Benefit Sharing regulation (ABS).

    PubMed

    Augusto, Carlos; Gutiérrez, Conde

    2014-01-01

    Synthetic biology is a change of paradigm, i.e. from the exploitation of natural and genetic resources to lab production of biological entities. This transitional shift represents a great challenge for developing countries, particularly those which host biodiversity, and users of genetic resources, since the latter might not be longer required to access to actual genetic resources (tangible genetic resources) but rather genetic resources' information (intangible genetic resources) in order to replicate those resources in labs. This could mean that users of genetic resource would not have to comply with the Convention on Biological Diversity (CBD) and its complementary treaty, the Nagoya Protocol, known also as the Access and Benefit Sharing regime (ABS). Both international instrument demands that States create legal mechanisms to secure access and benefit sharing, i.e., users of genetic resources are required to obtain prior informed consent (PIC) from host countries of biodiversity and reach mutual agreed terms (MATs), in which users and countries agree how to share the benefits arise from the utilization of genetic resources. The ABS regime is particularly relevant since its implementation at national and regional level has created tensions between users of genetic resources and developing countries. This situation could lead to users removing interest in the exploitation of genetic resources, subsequently, meaning that their focus would move towards technologies that rely less on tangible genetic resources, including synthetic biology. This papers aim to discuss the scope of the CBD and the Nagoya Protocol in the light of synthetic biology and the implications for developing countries. PMID:25845206

  14. Application of electrostatic separation to the recycling of plastic wastes: separation of PVC, PET, and ABS.

    PubMed

    Park, Chul-Hyun; Jeon, Ho-Seok; Yu, Hyo-Shin; Han, Oh-Hyung; Park, Jai-Koo

    2008-01-01

    Plastics are widely used in everyday life as a useful material, and thus their consumption is growing at a rate of about 5% per year in Korea. However, the constant generation of plastic wastes and their disposal generates environmental problems along with economic loss. In particular, mixed waste plastics are difficult to recycle because of their inferior characteristics. A laboratory-scale triboelectrostatic separator unit has been designed and assembled for this study. On the basis of the control of electrostatic charge, the separation of three kinds of mixed plastics, polyvinyl chloride (PVC), poly(ethylene terephthalate) (PET), and acrylonitrile-butadiene-styrene (ABS), in a range of similar gravities has been performed through a two-stage separation process. Polypropylene (PP) and high-impact polystyrene (HIPS) were found to be the most effective materials for a tribo-charger in the separation of PVC, PET, and ABS. The charge-to-mass ratio (nC/g) of plastics increased with increasing air velocity in the tribo charger. In the first stage, using the PP cyclone charger, the separation efficiency of particles considerably depended on the air velocity (10 m/s), the relative humidity (< 30%), the electrode potential (> 20 kV), and the splitter position (+2 cm from the center) in the triboelelctrostatic separator unit. At this time, a PVC grade of 99.40% and a recovery of 98.10% have successfully been achieved. In the second stage, using the HIPS cyclone charger, a PET grade of 97.80% and a recovery of 95.12% could be obtained under conditions of 10 m/s, over 25 kV, a central splitter position, and less than 40% relative humidity. In order to obtain 99.9% PVC grade and 99.3% PET grade, their recoveries should be sacrificed by 20.9% and 27%, respectively, with moving the splitter from the center to a (+)6 cm position. PMID:18350904

  15. 2. VIEW OF BLOCK AND TACKLE FOR MOVING CEDAR LOGS ...

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

    2. VIEW OF BLOCK AND TACKLE FOR MOVING CEDAR LOGS FROM POND TO JACK LADDER--AN ENDLESS CHAIN CONVEYOR THAT MOVES LOGS INTO MILL - Lester Shingle Mill, 1602 North Eighteenth Street, Sweet Home, Linn County, OR

  16. Collision avoidance of two moving objects using the anticipated path

    NASA Astrophysics Data System (ADS)

    Rhee, Seung Hak; Ahmad, Muhammad Bilal; Park, Seung-Jin; Beak, Kyoung-Ju; Park, Jong An

    2004-03-01

    Collision avoidance is one of the most important problems in autonomous vehicles, ship navigation, and robot manipulators, etc. Image processing technique could be applied for solving the collision avoidance of moving objects. The collision could be avoided if the direction of the moving object could be accurately anticipated. The problem is how to anticipate the expected path of the moving object, so that the other moving objects in the expected path should be detected and avoided for collision avoidance. Collisions could be avoided by searching the obstacles and moving objects in the expected path, but the moving objects, which would come inside the expected path, should also be detected for fully collision avoidance. In this paper, the expected path of the moving object is determined from the previous history of the moving object using the statistical measurements.

  17. Biosimilars advancements: Moving on to the future.

    PubMed

    Tsuruta, Lilian Rumi; Lopes dos Santos, Mariana; Moro, Ana Maria

    2015-01-01

    Many patents for the first biologicals derived from recombinant technology and, more recently, monoclonal antibodies (mAbs) are expiring. Naturally, biosimilars are becoming an increasingly important area of interest for the pharmaceutical industry worldwide, not only for emergent countries that need to import biologic products. This review shows the evolution of biosimilar development regarding regulatory, manufacturing bioprocess, comparability, and marketing. The regulatory landscape is evolving globally, whereas analytical structure and functional analyses provide the foundation of a biosimilar development program. The challenges to develop and demonstrate biosimilarity should overcome the inherent differences in the bioprocess manufacturing and physicochemical and biological characterization of a biosimilar compared to several lots of the reference product. The implementation of approaches, such as Quality by Design (QbD), will provide products with defined specifications in relation to quality, purity, safety, and efficacy that were not possible when the reference product was developed. Actually, the need to prove comparability to the reference product by the biosimilar industry has increased the knowledge about the product and the production-process associated by the use of powerful analytical tools. The technological challenges to make copies of biologic products while attending regulatory and market demands are expected to help innovation in the direction of attaining more productive manufacturing processes. PMID:25708573

  18. GJ 282 AB (WDS 07400-0336 AB = BGH 3 AB) and GICLAS 112-29: A Very Wide System in Process of Dissociation

    NASA Astrophysics Data System (ADS)

    Rica, F. M.; Benavides, R.

    2016-04-01

    Very wide binaries are interesting objects that shed light on the binary formation process and their dynamical evolution. Poveda et al. (2009) studied the possible physical relation of the near (14.2 pc) and wide (~58") binary star GJ 282 AB and the extremely wide (1.09º; ~55,000 AU) companion, NLTT 18149, and they concluded that this very wide system is in the process of dynamical disintegration. In this work, we confirm the same conclusion but using a different method. We first study dynamically GJ 282 AB, confirmed that it is a bound system and then we determine possible orbital solutions. Later, we calculate the relative velocity of NLTT 18149 with respect to the GJ 282 AB's center mass using their (U, V, W) galactocentric velocity. The relative velocity, Vrel = 1.98 ± 0.16 km s-1, is much larger than the escape velocity (0.25 ± 0.01 km s-1). Therefore, with a significance level of 11s, we also conclude that this very wide system is in a process of dynamical disintegration.

  19. DISCOVERY OF A YOUNG L DWARF BINARY, SDSS J224953.47+004404.6AB

    SciTech Connect

    Allers, K. N.; Liu, Michael C.; Dupuy, Trent J.; Cushing, Michael C.

    2010-05-20

    We report discovery of a young 0.''32 L dwarf binary, SDSS J2249+0044AB, found as the result of a Keck laser guide star adaptive optics imaging survey of young field brown dwarfs. Weak K I, Na I, and FeH features as well as strong VO absorption in the integrated-light J-band spectrum indicate a low surface gravity and hence young age for the system. From spatially resolved K-band spectra we determine spectral types of L3 {+-} 0.5 and L5 {+-} 1 for components A and B, respectively. SDSS J2249+0044A is spectrally very similar to G196-3B, an L3 companion to a young M2.5 field dwarf. Thus, we adopt 100 Myr (the age estimate of the G196-3 system) as the age of SDSS J2249+0044AB, but ages of 12-790 Myr are possible. By comparing our photometry to the absolute magnitudes of G196-3B, we estimate a distance to SDSS J2249+0044AB of 54 {+-} 16 pc and infer a projected separation of 17 {+-} 5 AU for the binary. Comparison of the luminosities to evolutionary models at an age of 100 Myr yields masses of 0.029 {+-} 0.006 and 0.022{sup +0.006}{sub -0.009} M{sub sun} for SDSS J2249+0044A and B, respectively. Over the possible ages of the system (12-790 Myr), the mass of SDSS J2249+0044A could range from 0.011 to 0.070 M{sub sun} and the mass of SDSS J2249+0044B could range from 0.009 to 0.065 M{sub sun}. Evolutionary models predict that either component could be burning deuterium, which could result in a mass ratio as low as 0.4, or alternatively, a reversal in the luminosities of the binary. We find a likely proper motion companion, GSC 00568-01752, which lies 48.''9 away (a projected separation of 2600 AU) and has Sloan Digital Sky Survey and Two Micron All Sky Survey colors consistent with an early M dwarf. We calculate a photometric distance to GSC 00568-01752 of 53 {+-} 15 pc, in good agreement with our distance estimate for SDSS J2249+0044AB. The space motion of SDSS J2249+0044AB shows no obvious coincidence with known young moving groups, though radial velocity and parallax

  20. High-precision Radio and Infrared Astrometry of LSPM J1314+1320AB. II. Testing Pre-main-sequence Models at the Lithium Depletion Boundary with Dynamical Masses

    NASA Astrophysics Data System (ADS)

    Dupuy, Trent J.; Forbrich, Jan; Rizzuto, Aaron; Mann, Andrew W.; Aller, Kimberly; Liu, Michael C.; Kraus, Adam L.; Berger, Edo

    2016-08-01

    We present novel tests of pre-main-sequence models based on individual dynamical masses for the M7 binary LSPM J1314+1320AB. Joint analysis of Keck adaptive optics astrometric monitoring along with Very Long Baseline Array radio data from a companion paper yield component masses of 92.8 ± 0.6 M Jup (0.0885 ± 0.0006 M ⊙) and 91.7 ± 1.0 M Jup (0.0875 ± 0.0010 M ⊙) and a parallactic distance of 17.249 ± 0.013 pc. We find component luminosities consistent with the system being coeval at 80.8 ± 2.5 Myr, according to BHAC15 evolutionary models. The presence of lithium is consistent with model predictions, marking the first test of the theoretical lithium depletion boundary using ultracool dwarfs of known mass. However, we find that the evolutionary model-derived average effective temperature (2950 ± 5 K) is 180 K hotter than that given by a spectral type–{T}{eff} relation based on BT-Settl models (2770 ± 100 K). We suggest that the dominant source of this discrepancy is model radii being too small by ≈13%. In a test mimicking the typical application of models by observers, we derive masses on the H-R diagram using luminosity and BT-Settl temperature. The estimated masses are lower by {46}-19+16 % (2.0σ) than we measure dynamically and would imply that this is a system of ≈50 M Jup brown dwarfs, highlighting the large systematic errors possible in H-R diagram properties. This is the first time masses have been measured for ultracool (≥M6) dwarfs displaying spectral signatures of low gravity. Based on features in the infrared, LSPM J1314+1320AB appears to have higher gravity than typical Pleiades and AB Dor members, opposite the expectation given its younger age. The components of LSPM J1314+1320AB are now the nearest, lowest mass pre-main-sequence stars with direct mass measurements. Data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the

  1. Moving House for Education in the Pre-School Years

    ERIC Educational Resources Information Center

    Hansen, Kirstine

    2014-01-01

    This paper uses data from the Millennium Cohort Study (MCS) to examine house moves that take place in the pre-school years, focusing on families who move for the education of their children. We present results showing that education- related house moves do indeed occur in the pre-school years with particular types of parents making these…

  2. 30 CFR 57.14107 - Moving machine parts.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Moving machine parts. 57.14107 Section 57.14107 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... Equipment Safety Devices and Maintenance Requirements § 57.14107 Moving machine parts. (a) Moving...

  3. 30 CFR 56.14107 - Moving machine parts.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Moving machine parts. 56.14107 Section 56.14107 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... Safety Devices and Maintenance Requirements § 56.14107 Moving machine parts. (a) Moving machine...

  4. 30 CFR 57.14107 - Moving machine parts.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Moving machine parts. 57.14107 Section 57.14107 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... Equipment Safety Devices and Maintenance Requirements § 57.14107 Moving machine parts. (a) Moving...

  5. 30 CFR 56.14107 - Moving machine parts.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Moving machine parts. 56.14107 Section 56.14107 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... Safety Devices and Maintenance Requirements § 56.14107 Moving machine parts. (a) Moving machine...

  6. 30 CFR 56.14107 - Moving machine parts.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Moving machine parts. 56.14107 Section 56.14107 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... Safety Devices and Maintenance Requirements § 56.14107 Moving machine parts. (a) Moving machine...

  7. 30 CFR 56.14107 - Moving machine parts.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Moving machine parts. 56.14107 Section 56.14107 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... Safety Devices and Maintenance Requirements § 56.14107 Moving machine parts. (a) Moving machine...

  8. 30 CFR 56.14107 - Moving machine parts.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Moving machine parts. 56.14107 Section 56.14107 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... Safety Devices and Maintenance Requirements § 56.14107 Moving machine parts. (a) Moving machine...

  9. 30 CFR 57.14107 - Moving machine parts.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Moving machine parts. 57.14107 Section 57.14107 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... Equipment Safety Devices and Maintenance Requirements § 57.14107 Moving machine parts. (a) Moving...

  10. 30 CFR 57.14107 - Moving machine parts.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Moving machine parts. 57.14107 Section 57.14107 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... Equipment Safety Devices and Maintenance Requirements § 57.14107 Moving machine parts. (a) Moving...

  11. 30 CFR 57.14107 - Moving machine parts.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Moving machine parts. 57.14107 Section 57.14107 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... Equipment Safety Devices and Maintenance Requirements § 57.14107 Moving machine parts. (a) Moving...

  12. Home Is Where the Family Is: Moving House with Children.

    ERIC Educational Resources Information Center

    Linke, Pam

    2000-01-01

    This publication is intended to help parents address their children's needs and emotions when the family is moving from one place to another. Detailed information and tips are provided on several moving-related issues, including: (1) how children respond to change; (2) how parents respond to change; (3) preparing children for the move; (4) the…

  13. 30 CFR 56.7053 - Moving hand-held drills.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Moving hand-held drills. 56.7053 Section 56.7053 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... Jet Piercing Drilling § 56.7053 Moving hand-held drills. Before hand-held drills are moved from...

  14. 30 CFR 56.7053 - Moving hand-held drills.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Moving hand-held drills. 56.7053 Section 56.7053 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... Jet Piercing Drilling § 56.7053 Moving hand-held drills. Before hand-held drills are moved from...

  15. 30 CFR 56.7053 - Moving hand-held drills.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Moving hand-held drills. 56.7053 Section 56.7053 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... Jet Piercing Drilling § 56.7053 Moving hand-held drills. Before hand-held drills are moved from...

  16. 30 CFR 56.7053 - Moving hand-held drills.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Moving hand-held drills. 56.7053 Section 56.7053 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... Jet Piercing Drilling § 56.7053 Moving hand-held drills. Before hand-held drills are moved from...

  17. 30 CFR 56.7053 - Moving hand-held drills.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Moving hand-held drills. 56.7053 Section 56.7053 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... Jet Piercing Drilling § 56.7053 Moving hand-held drills. Before hand-held drills are moved from...

  18. 30 CFR 57.7008 - Moving the drill.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Moving the drill. 57.7008 Section 57.7008... SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling-Surface Only § 57.7008 Moving the drill. When a drill is being moved from...

  19. 30 CFR 57.7008 - Moving the drill.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Moving the drill. 57.7008 Section 57.7008... SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling-Surface Only § 57.7008 Moving the drill. When a drill is being moved from...

  20. 30 CFR 56.7008 - Moving the drill.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Moving the drill. 56.7008 Section 56.7008... SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling § 56.7008 Moving the drill. When a drill is being moved from one drilling area to...

  1. 30 CFR 56.7008 - Moving the drill.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Moving the drill. 56.7008 Section 56.7008... SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling § 56.7008 Moving the drill. When a drill is being moved from one drilling area to...

  2. 30 CFR 56.7008 - Moving the drill.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Moving the drill. 56.7008 Section 56.7008... SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling § 56.7008 Moving the drill. When a drill is being moved from one drilling area to...

  3. 30 CFR 56.7008 - Moving the drill.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Moving the drill. 56.7008 Section 56.7008... SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling § 56.7008 Moving the drill. When a drill is being moved from one drilling area to...

  4. 30 CFR 57.7008 - Moving the drill.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Moving the drill. 57.7008 Section 57.7008... SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling-Surface Only § 57.7008 Moving the drill. When a drill is being moved from...

  5. 30 CFR 57.7008 - Moving the drill.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Moving the drill. 57.7008 Section 57.7008... SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling-Surface Only § 57.7008 Moving the drill. When a drill is being moved from...

  6. 30 CFR 57.7008 - Moving the drill.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Moving the drill. 57.7008 Section 57.7008... SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling-Surface Only § 57.7008 Moving the drill. When a drill is being moved from...

  7. 30 CFR 56.7008 - Moving the drill.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Moving the drill. 56.7008 Section 56.7008... SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling § 56.7008 Moving the drill. When a drill is being moved from one drilling area to...

  8. A-B Distinction in a Sample of Prominent Psychotherapists

    ERIC Educational Resources Information Center

    Geller, Jesse D.; Berzins, Juris I.

    1976-01-01

    A sample of prominent psychotherapists were asked to fill out the A-B therapist "type" scale and comment on their possible differential effectiveness in treating schizoid/schizophrenic versus neurotic patients. The data suggest that B therapists desire and seek more complex and exciting sensory-cognitive inputs during therapy hours than A…

  9. Motif based Hessian matrixfor ab initio geometry optimization ofnanostructures

    SciTech Connect

    Zhao, Zhengji; Wang, Lin-Wang; Meza, Juan

    2006-04-05

    A simple method to estimate the atomic degree Hessian matrixof a nanosystem is presented. The estimated Hessian matrix, based on themotif decomposition of the nanosystem, can be used to accelerate abinitio atomic relaxations with speedups of 2 to 4 depending on the sizeof the system. In addition, the programing implementation for using thismethod in a standard ab initio package is trivial.

  10. Environmentally friendly process for nickel electroplating of ABS

    NASA Astrophysics Data System (ADS)

    Bazzaoui, M.; Martins, J. I.; Bazzaoui, E. A.; Albourine, A.

    2012-08-01

    Nickel electroplating of acrylonitrile butadiene styrene (ABS) plastic has been achieved successfully without any chromium or palladium pretreatment. Once the ABS is coated with polypyrrole (PPy), the sample may be electroplated. The process is fast, economic and involves three stages. Firstly, chemical deposition of PPy on ABS, secondly, copper deposition and finally nickel electroplating. A homogenous and adherent PPy has been synthesized chemically on ABS plate by using pyrrole as monomer and iron (III) chloride as oxidant. Copper and nickel were deposited galvanostatically from industrial plating baths. The metallic coatings were homogeneous and the adherence was estimated at 100%. The thickness of copper and nickel depend on the electrolysis time. As the current density increases, the Cu and Ni thickness raises. This result was confirmed from SEM characterization and RX map. The Ni coating is characterized by a globular structure with globules of different sizes. Energy dispersive X-ray spectroscopy (EDS) analysis shows the presence of Ni with some amount of carbon and oxygen due to the nickel oxides and contaminant from the bath solution.

  11. Nonreactive Measuring: Its Time Has Arrived with AB 65.

    ERIC Educational Resources Information Center

    Freda, James A.

    1978-01-01

    This article includes school improvement variables to be considered in the evaluation of school improvement under the provisions of California's AB 65. The variables are categorized as pupil and teacher attitudes, instructional methods involving pupils and teachers, and school plant data. (Author)

  12. Towards SiC Surface Functionalization: An Ab Initio Study

    SciTech Connect

    Cicero, G; Catellani, A

    2005-01-28

    We present a microscopic model of the interaction and adsorption mechanism of simple organic molecules on SiC surfaces as obtained from ab initio molecular dynamics simulations. Our results open the way to functionalization of silicon carbide, a leading candidate material for bio-compatible devices.

  13. Inhibited fragmentation of mAbs in buffered ionic liquids.

    PubMed

    Mazid, Romiza R; Vijayaraghavan, R; MacFarlane, Douglas R; Cortez-Jugo, Christina; Cheng, Wenlong

    2015-05-11

    We thoroughly investigated the biological, structural and chemical stability of epidermal growth factor receptor monoclonal antibody (EGFR mAb) using choline-based buffered ionic liquids (BILs). The results demonstrated substantially enhanced stabilities in our BILs, indicating their huge promise as real-world green biological buffers for antibody storage and transportation. PMID:25869239

  14. Ab initio pseudopotential band calculation of organic conductors

    SciTech Connect

    Ishibashi, Shoji; Kohyama, Masanori

    1999-12-01

    The authors have calculated the band structures of organic conductors TTF-TCNQ and {beta}-(BEDT-TTF){sub 2}I{sub 3} using the ab initio plane-wave pseudopotential method within the local-density approximation (LDA). The Fermi-surface shape and the origin of bands near the Fermi level are investigated for each compound.

  15. Multiple time step integrators in ab initio molecular dynamics

    SciTech Connect

    Luehr, Nathan; Martínez, Todd J.; Markland, Thomas E.

    2014-02-28

    Multiple time-scale algorithms exploit the natural separation of time-scales in chemical systems to greatly accelerate the efficiency of molecular dynamics simulations. Although the utility of these methods in systems where the interactions are described by empirical potentials is now well established, their application to ab initio molecular dynamics calculations has been limited by difficulties associated with splitting the ab initio potential into fast and slowly varying components. Here we present two schemes that enable efficient time-scale separation in ab initio calculations: one based on fragment decomposition and the other on range separation of the Coulomb operator in the electronic Hamiltonian. We demonstrate for both water clusters and a solvated hydroxide ion that multiple time-scale molecular dynamics allows for outer time steps of 2.5 fs, which are as large as those obtained when such schemes are applied to empirical potentials, while still allowing for bonds to be broken and reformed throughout the dynamics. This permits computational speedups of up to 4.4x, compared to standard Born-Oppenheimer ab initio molecular dynamics with a 0.5 fs time step, while maintaining the same energy conservation and accuracy.

  16. Discovery of New Substrates for LuxAB Bacterial Bioluminescence.

    PubMed

    Jiang, Tianyu; Wang, Weishan; Wu, Xingkang; Wu, Wenxiao; Bai, Haixiu; Ma, Zhao; Shen, Yuemao; Yang, Keqian; Li, Minyong

    2016-08-01

    In this article, four novel substrates with long halftime have been designed and synthesized successfully for luxAB bacterial bioluminescence. After in vitro and in vivo biological evaluation, these molecules can emit obvious bioluminescence emission with known bacterial luciferase, thus indicating a new promising approach to developing the bacterial bioluminescent system. PMID:26896339

  17. Environmental Study: Science and Engineering Buildings. ABS Publication No. 1.

    ERIC Educational Resources Information Center

    California Univ., Berkeley.

    This report is the first of a series which present the results of a systems analysis of the problem of providing science and engineering buildings at the university level conducted by the Academic Building Systems (ABS) program. The document includes (1) a user survey (data and conclusions from a series of studies involving a spectrum of…

  18. AB 1725 Model Accountability System. California Community Colleges. Revised.

    ERIC Educational Resources Information Center

    California Community Colleges, Sacramento. Board of Governors.

    This report proposes a model accountability system for the California community colleges to comply with the directives of Assembly Bill 1725 (AB 1725). The purpose of the accountability system is to provide colleges and districts, the board of governors, and the California legislature with information that will allow for the continued improvement…

  19. Information Manual: Procedures, Planning Concepts, Subsystems. ABS Publication No. 3.

    ERIC Educational Resources Information Center

    California Univ., Berkeley.

    This report, the third in a series which presents the results of a systems analysis of the problem of providing science and engineering buildings at the university level, is a technical manual for using the Academic Building Systems (ABS) approach in programing, designing, and constructing such facilities. The document presents (1) planning…

  20. Modeling and simulation research on automobile ABS bench detection

    NASA Astrophysics Data System (ADS)

    Hao, Ruru; Zhao, Xiangmo; Hao, Dingkun; Zhou, Zhou

    2014-10-01

    Modeling and simulation research on automobile ABS bench detection is conducted in this paper. First, the vehicle model, wheel model, braking force model, and tire-road model on the bench are established according to the ABS bench detection scheme. Then, the Matlab/Simulink simulation model of a single wheel vehicle is built through combining the sub-models described above. Finally, simulation experiments on a variety of simulated road conditions are carried out. And the comparative analysis between the ABS bench detection and ABS road experiments is accomplished. The contrast results show that the simulation curves of bench detection and those of road experiment have high similarity, which verified the correctness and feasibility of the proposed bench detection scheme. At the request of the authors this article is being retracted. It was inadvertently published in AIP Conf. Proc. 1618: The authors intended to publish a different article, but the wrong one was submitted for publication. The article is retracted from the scientific record with effect from 8 July 2015.

  1. Dialkylimidazolium chloroaluminates: Ab initio calculations, Raman and neutron scattering measurements

    SciTech Connect

    Takahasi, S. ); Curtiss, L.A.; Gosztola, D.; Koura, N. ); Loong, C.K.; Saboungi, M.L. . Materials Science Div.)

    1993-04-01

    The Raman and neutron scattering spectra of 46 mol% AlCl[sub 3] -54 mol% 1-ethyl-3-methyl imidazolium chloride (EMIC) and 67 mol% AlCl[sub 3] - 33 mol% EMIC melts are presented. Ab initio molecular orbital calculations have been carried out on structures of chloroaluminate anion and EMI cation and the interaction between anion and cation.

  2. Antigraviceptive neck muscle responses to "moving up and moving down" in human

    NASA Technical Reports Server (NTRS)

    Aoki, M.; Han, X. Y.; Yamada, H.; Muto, T.; Satake, H.; Ito, Y.; Matsunami, K.

    2000-01-01

    The responses of neck muscle to sudden transit from one 'g' to hyper 'g', work to support the head and remain the relative position of head on trunk as common observed: i.e. in sudden acceleration or deceleration by car or ejection of pilot from aircraft. Accordingly it is highly possible that the neck muscle responses to moving up may be important to prevent the neck injury due to sudden linear acceleration such as moving up against gravity. However little is known about the evaluation of mechanism of this reflex. Therefore the present study was conducted with two aims. The first aim was to investigate the neck muscle responses to vertical linear acceleration bv 0.4 g produced with an electro-hydraulic servo-system. We chose the vertical linear acceleration because it activates mainly sacculus, from which afferents have been demonstrated to be connected directly to sternocleidomastoid muscle in animals and human. The second aim was to determine whether there is a difference of neck muscle response to moving down and moving up.

  3. 25 CFR 700.157 - Actual reasonable moving and related expenses-nonresidential moves.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... certification required by the displaced person, to the extent such cost is (i) necessary to its re-establishment... expenses that are not listed as ineligible under § 700.165. (b) Self-move. If the displaced person self... Commission and inspection. To be eligible for a payment under this section, the displaced person shall...

  4. Tracking move-stop-move targets with state-dependent mode transition probabilities

    NASA Astrophysics Data System (ADS)

    Zhang, Shuo; Bar-Shalom, Yaakov

    2009-08-01

    This paper presents a novel method for tracking ground moving targets with a GMTI radar. To avoid detection by the GMTI radar, targets can deliberately stop for some time before moving again. The GMTI radar does not detect a target when the radial velocity (along the line-of-sight from the sensor) falls below a certain minimum detectable velocity (MDV). We develop a new approach by using state-dependent mode transition probabilities to track move-stop-move targets. Since in a real scenario, the maximum deceleration is always limited, a target can not switch to the stopped-target model from a high speed. Therefore, with the use of the stopped-target model, the Markov chain of the mode switching has jump probabilities that depend on the target's kinematic state. A mode transition matrix with zero jump probabilities to the stopped-target mode is used when the speed is above a certain "stopping" limit (above which the target cannot stop in one sampling interval, designated as "fast stage") and another transition matrix with non-zero jump probabilities to the stopped-target mode is used when the speed is below this limit (designated as "slow stage"). The stage probabilities are calculated using the kinematic state statistics from the IMM estimator and then used to combine the state-dependent mode transition probabilities (SDP) in the two different transition matrices. The experimental results show that the proposed algorithm outperforms previous methods.

  5. About Leaving: Making Sense of Moving On [and] Commentary: Making Sense of Moving On.

    ERIC Educational Resources Information Center

    Banham, Ken; Garrett, Malcolm; McClean, Arlene; Strydom, Andre; Hassiotis, Angela; Williams, Val; Palmer, Neil; England, Tiffany

    2003-01-01

    This article is written by two British people with learning disabilities and their health care team. It is about their wish to move into homes in the community after years in hospitals. They explain the service experiences they have had and what they are looking forward to in the future. (CR)

  6. Adaptive moving mesh methods for simulating one-dimensional groundwater problems with sharp moving fronts

    USGS Publications Warehouse

    Huang, W.; Zheng, Lingyun; Zhan, X.

    2002-01-01

    Accurate modelling of groundwater flow and transport with sharp moving fronts often involves high computational cost, when a fixed/uniform mesh is used. In this paper, we investigate the modelling of groundwater problems using a particular adaptive mesh method called the moving mesh partial differential equation approach. With this approach, the mesh is dynamically relocated through a partial differential equation to capture the evolving sharp fronts with a relatively small number of grid points. The mesh movement and physical system modelling are realized by solving the mesh movement and physical partial differential equations alternately. The method is applied to the modelling of a range of groundwater problems, including advection dominated chemical transport and reaction, non-linear infiltration in soil, and the coupling of density dependent flow and transport. Numerical results demonstrate that sharp moving fronts can be accurately and efficiently captured by the moving mesh approach. Also addressed are important implementation strategies, e.g. the construction of the monitor function based on the interpolation error, control of mesh concentration, and two-layer mesh movement. Copyright ?? 2002 John Wiley and Sons, Ltd.

  7. 49 CFR 24.305 - Fixed payment for moving expenses-nonresidential moves.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... displacement and for which an expense would be incurred in such move and, the business vacates or relocates from its displacement site; (2) The business cannot be relocated without a substantial loss of its...) The business is not operated at a displacement dwelling solely for the purpose of renting...

  8. 9 CFR 316.8 - Unmarked inspected products; moved between official establishments; moved in commerce.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... between official establishments; moved in commerce. 316.8 Section 316.8 Animals and Animal Products FOOD... establishment to another official establishment, for further processing, in a railroad car, truck, or other closed container, if the railroad car, truck, or container is sealed with an official seal of...

  9. 9 CFR 316.8 - Unmarked inspected products; moved between official establishments; moved in commerce.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... between official establishments; moved in commerce. 316.8 Section 316.8 Animals and Animal Products FOOD... establishment to another official establishment, for further processing, in a railroad car, truck, or other closed container, if the railroad car, truck, or container is sealed with an official seal of...

  10. 9 CFR 316.8 - Unmarked inspected products; moved between official establishments; moved in commerce.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... between official establishments; moved in commerce. 316.8 Section 316.8 Animals and Animal Products FOOD... establishment to another official establishment, for further processing, in a railroad car, truck, or other closed container, if the railroad car, truck, or container is sealed with an official seal of...

  11. 9 CFR 316.8 - Unmarked inspected products; moved between official establishments; moved in commerce.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... between official establishments; moved in commerce. 316.8 Section 316.8 Animals and Animal Products FOOD... establishment to another official establishment, for further processing, in a railroad car, truck, or other closed container, if the railroad car, truck, or container is sealed with an official seal of...

  12. 9 CFR 316.8 - Unmarked inspected products; moved between official establishments; moved in commerce.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... between official establishments; moved in commerce. 316.8 Section 316.8 Animals and Animal Products FOOD... establishment to another official establishment, for further processing, in a railroad car, truck, or other closed container, if the railroad car, truck, or container is sealed with an official seal of...

  13. Particle transport in a moving corner

    NASA Astrophysics Data System (ADS)

    Laine-Pearson, F. E.; Hydon, P. E.

    2006-07-01

    This paper describes particle transport in Stokes flow in a two-dimensional corner whose walls oscillate, which is a simple model for particle transport in the pulmonary alveoli. Formally speaking, the wall motion produces a perturbation to the well-known Moffatt corner eddies. However, this ‘perturbation’ is dominant as the corner is approached. The motion of particles is regular near to the corner. Far from the corner, chaotic motion within the main part of the flow is restricted to very small regions. We deduce that there is competition between the far-field motion that generates eddies and the wall motion. The relative strengths of these two motions determines whether a given particle moves regularly or chaotically. Consequently, there is an intermediate region in which chaotic transport is maximized.

  14. Kinetics of a Fast Moving Partial Dislocation

    NASA Astrophysics Data System (ADS)

    Daphalapurkar, Nitin; Ramesh, K. T.

    2013-03-01

    Plastic deformation in materials under extreme stresses requires a kinetic description of moving dislocations. The velocities with which the partial dislocations can propagate under an applied stress has implications for plasticity at high strain rates, specifically, the rate of plastic deformation and the rate-sensitivity. In this work, we focus our attention on motion of a twinning partial dislocation in a face-centered cubic (FCC) material, Ni. We use molecular dynamics simulations to simulate the velocity of a propagating twinning partial dislocation and investigate the effect of applied shear stress. Results suggest a limiting value for the speeds of a propagating partial dislocation. The material speeds based on the nonlinear part (under high stresses) of the stress-strain curve are shown to have an influence on the velocity with which a partial dislocation can propagate. Predicted velocities from simulations will be related to observations from high rate impact experiments. Supported by Hopkins Extreme Materials Institute

  15. Dynamical moving mirrors and black holes

    NASA Astrophysics Data System (ADS)

    Chung, Tze-Dan; Verlinde, Herman

    1994-04-01

    A simple quantum mechanical model of N free scalar fields interacting with a dynamical moving mirror is formulated and shown to be equivalent to two-dimensional dilaton gravity. We derive the semi-classical dynamics of this system, by including the back reaction due to the quantum radiation. We develop a hamiltonian formalism that describes the time evolution as seen by an asymptotic observer, and write a scattering equation that relates the in-falling and out-going modes at low energies. At higher incoming energy flux, however, the semi-classical model appears to become unstable and the mirror seems to accelerate forever along a trajectory that runs off to infinity. This instability provides a useful paradigm for black hole formation and introduces an analogous information paradox. Finally, we indicate a possible mechanism that may restore the stability of the system at the quantum level without destroying quantum coherence.

  16. Dynamical moving mirrors and black holes.

    NASA Astrophysics Data System (ADS)

    Tzedan, Chung; Verlinde, H.

    1994-04-01

    A simple quantum mechanical model of N free scalar fields interacting with a dynamical moving mirror is formulated and shown to be equivalent to two-dimensional dilaton gravity. The authors derive the semi-classical dynamics of this system, by including the back reaction due to the quantum radiation. They develop a hamiltonian formalism that describes the time evolution as seen by an asymptotic observer, and write a scattering equation that relates the in-falling and out-going modes at low energies. At higher incoming energy flux, however, the semi-classical model appears to become unstable and the mirror seems to accelerate forever along a trajectory that runs off to infinity. This instability provides a useful paradigm for black hole formation and introduces an analogous information paradox.

  17. Moving stormwater P management upstream (Invited)

    NASA Astrophysics Data System (ADS)

    Baker, L. A.; Hobbie, S. E.; Finlay, J. C.; Kalinosky, P.; Janke, B.

    2013-12-01

    Reducing stormwater phosphorus loading using current approaches, which focus on treatment at the end of the pipe, is unlikely to reduce P loads enough to restore nutrient-impaired urban lakes. An indication of this is that of the nearly 150 nutrient impaired lakes in the Twin Cities region, only one has been restored. We hypothesize that substantial reduction of eutrophication will require reductions of P inputs upstream from storm drains. Developing source reduction strategies will required a shift in thinking about system boundaries, moving upstream from the storm drain to the curb, and from the curb to the watershed. Our Prior Lake Street Sweeping Project, a 2-year study of enhanced street sweeping, will be used to illustrate the idea of moving the system boundary to the curb. This study showed that P load recovery from sweeping increases with both sweeping frequency and overhead tree canopy cover. For high canopy streets, coarse organic material (tree leaves; seed pods, etc.) comprised 42% of swept material. We estimate that P inputs from trees may be half of measured storm P yields in 8 urban catchments in St. Paul, MN. Moreover, the cost of removing P during autumn was often < 100/pound P, compared with > 1000/lb P for stormwater ponds. We can also move further upstream, to the watershed boundary. P inputs to urban watersheds that enter lawns include lawn fertilizer, polyphosphates added to water supplies (and hence to lawns via irrigation), and pet food (transformed to pet waste). Minnesota enacted a lawn P fertilizer restriction in 2003, but early reductions in stormwater P loads were modest, probably reflecting reduction in direct wash-off of applied fertilizer. Because urban soils are enriched in P, growing turf has continued to extract available soil P. When turf is mowed, cut grass decomposes, generating P in runoff. As soil P becomes depleted, P concentrations in lawn runoff will gradually decline. Preliminary modeling suggests that substantial

  18. Surface surveillance for ground moving targets indicators

    NASA Astrophysics Data System (ADS)

    Hsu, Charles; Szu, Harold

    2014-05-01

    Ground moving target indication (GMTI) using multiple resolutions of synthetic aperture radar (SAR) images to estimate the clutter scattering statistics can help transform Intelligence, Surveillance, and Reconnaissance (ISR), a mission area essential to the U.S. battlefield information advantage, because it can depict vehicular movement of enemy forces in near-real time throughout a large area in all-weather situations including fires, sand storm, and brown out, etc. Significant progress has been made in many aspects of GMTI since 1960s, but many challenges remain. These challenges include sensor development, signal processing, and target-recognition technology. This article describes in GMTI technologies that were developed for both airborne and ground-based surface surveillance.

  19. Optimal Control of Flows in Moving Domains

    NASA Astrophysics Data System (ADS)

    Protas, Bartosz; Liao, Wenyuan; Glander, Donn

    2006-11-01

    This investigation concerns adjoint--based optimization of viscous incompressible flows (the Navier-Stokes problem) coupled with heat conduction involving change of phase (the Stefan problem) and occurring in domains with moving boundaries such as the free and solidification surfaces. This problem is motivated by optimization of advanced welding techniques used in automotive manufacturing. We characterize the sensitivity of a suitable cost functional defined for the system with respect to control (the heat input) using adjoint equations. Given that the shape of the domain is also a dependent variable, characterizing sensitivities necessitates the introduction of ``non-cylindrical'' calculus required to differentiate a cost functional defined on a variable domain. As a result, unlike the forward problem, the adjoint system is defined on a domain with a predetermined evolution in time and also involves ordinary differential equations defined on the domain boundary (``the adjoint transverse system''). We will discuss certain computational issues related to numerical solution of such adjoint problems.

  20. Casimir effect with uniformly moving mirrors

    SciTech Connect

    Bordag, M.; Dittes, F.; Robaschik, D.

    1986-06-01

    We study a simple example of quantum electrodynamics with nonstationary boundary conditions in (3+1) dimensions: the problem of two parallel mirrors moving relative to each other with constant speed v. The Green functions are constructed using the reflection principle. The behavior of physical quantities like the Casimir force and the vacuum expectation value of the energy-momentum tensor are discussed. If the motion of an arbitrary point between the mirrors is described by a straight world line, then in the local rest frame at the point in question the energy-momentum tensor has the same structure as in the standard Casimir problem with stationary mirrors. In particular, all physical quantities are smooth functions of v, so that the limit v..-->..0 leads to the expected results.

  1. Emil Cohn's electrodynamics of moving bodies

    NASA Astrophysics Data System (ADS)

    Darrigol, Olivier

    1995-10-01

    A now forgotten figure, Emil Cohn was one of the leading experts in electrodynamics at the turn of the century. Unsatisfied with Lorentz's electron theory, he proposed an alternative electrodynamics of moving bodies based on a modification of Maxwell's macroscopic field equations that managed to account for all relevant electrodynamic and optical experiments, including that of Michelson and Morley. Some of his insights foreshadow aspects of Einstein's relativity theory, especially the elimination of the ether and the criticism of Lorentz's implicit distinction between true and measured coordinates of space and time. However, Cohn did not believe in the general validity of the relativity principle, and did not require a revision of the usual concepts of space and time.

  2. STS-102 MPLM Leonardo moves into PCR

    NASA Technical Reports Server (NTRS)

    2001-01-01

    KENNEDY SPACE CENTER, Fla. -- In the payload changeout room on the Rotating Service Structure, Launch Pad 39B, workers move the Multi-Purpose Logistics Module Leonardo out of the payload canister. From the PCR Leonardo then will be transferred into Space Shuttle Discovery'''s payload bay. One of Italy'''s major contributions to the International Space Station program, Leonardo is a reusable logistics carrier. It is the primary delivery system used to resupply and return Station cargo requiring a pressurized environment. Leonardo is the primary payload on mission STS-102 and will deliver up to 10 tons of laboratory racks filled with equipment, experiments and supplies for outfitting the newly installed U.S. Laboratory Destiny. STS-102 is scheduled to launch March 8 at 6:45 a.m. EST.

  3. Nonlinear dynamics of axially moving plates

    NASA Astrophysics Data System (ADS)

    Ghayesh, Mergen H.; Amabili, Marco; Païdoussis, Michael P.

    2013-01-01

    The nonlinear dynamics for forced motions of an axially moving plate is numerically investigated using Von Kármán plate theory and retaining in-plane displacements and inertia. The equations of motion are obtained via an energy method based on Lagrange equations. This yields a set of second-order nonlinear ordinary differential equations with coupled terms. The equations are transformed into a set of first-order nonlinear ordinary differential equations and are solved via the pseudo-arclength continuation technique. The near-resonance nonlinear dynamics is examined via plotting the frequency-response curves of the system. Results are shown through frequency-response curves, time histories, and phase-plane diagrams. The effect of system parameters, such as the axial speed and the pretension, on the resonant responses is also highlighted.

  4. Underwater imaging with a moving acoustic lens.

    PubMed

    Kamgar-Parsi, B; Rosenblum, L J; Belcher, E O

    1998-01-01

    The acoustic lens is a high-resolution, forward-looking sonar for three dimensional (3-D) underwater imaging. We discuss processing the lens data for recreating and visualizing the scene. Acoustical imaging, compared to optical imaging, is sparse and low resolution. To achieve higher resolution, we obtain a denser sample by mounting the lens on a moving platform and passing over the scene. This introduces the problem of data fusion from multiple overlapping views for scene formation, which we discuss. We also discuss the improvements in object reconstruction by combining data from several passes over an object. We present algorithms for pass registration and show that this process can be done with enough accuracy to improve the image and provide greater detail about the object. The results of in-water experiments show the degree to which size and shape can be obtained under (nearly) ideal conditions. PMID:18267382

  5. Moving-objects extraction in diving video

    NASA Astrophysics Data System (ADS)

    Li, Yong; Liao, Qingmin

    2003-05-01

    This paper proposes a semiautomatic algorithm for the accurate extraction of an athlete from color diving sequences. Change detection techniques and edge detection techniques are combined to extract the moving object. Color information and interactive information are used to get rough region of the athlete interested. A robust edge map is derived from the difference between successive frames, then further refining of rough athlete region is applied by the information of the robust edge. The proposed method is useful in applications with a relatively still background, Experimental results show that the method provides accurate extraction with pixel-wise precision, thus providing a reliable input to further analysis or applications such as MPEG-4.

  6. Plasma waves and jets from moving conductors

    NASA Astrophysics Data System (ADS)

    Gralla, Samuel E.; Zimmerman, Peter

    2016-06-01

    We consider force-free plasma waves launched by the motion of conducting material through a magnetic field. We develop a spacetime-covariant formalism for perturbations of a uniform magnetic field and show how the transverse motion of a conducting fluid acts as a source. We show that fast-mode waves are sourced by the compressibility of the fluid, with incompressible fluids launching a pure-Alfvén outflow. Remarkably, this outflow can be written down in closed form for an arbitrary time-dependent, nonaxisymmetric incompressible flow. The instantaneous flow velocity is imprinted on the magnetic field and transmitted away at the speed of light, carrying detailed information about the conducting source at the time of emission. These results can be applied to transients in pulsar outflows and to jets from neutron stars orbiting in the magnetosphere of another compact object. We discuss jets from moving conductors in some detail.

  7. Rapidly Moving Divertor Plates In A Tokamak

    SciTech Connect

    S. Zweben

    2011-05-16

    It may be possible to replace conventional actively cooled tokamak divertor plates with a set of rapidly moving, passively cooled divertor plates on rails. These plates would absorb the plasma heat flux with their thermal inertia for ~10-30 sec, and would then be removed from the vessel for processing. When outside the tokamak, these plates could be cooled, cleaned, recoated, inspected, and then returned to the vessel in an automated loop. This scheme could provide nearoptimal divertor surfaces at all times, and avoid the need to stop machine operation for repair of damaged or eroded plates. We describe various possible divertor plate designs and access geometries, and discuss an initial design for a movable and removable divertor module for NSTX-U.

  8. An infant not moving her leg.

    PubMed

    Berkowitz, Tal; Young, Deborah

    2016-04-01

    A 4-week-old female infant presented to the emergency department (ED) due to a 1-week history of not moving her left lower extremity as well as crying during diaper changes. She had been seen 6 days prior at an ED, had normal x-rays, and was discharged home. The infant was afebrile and well appearing and had been feeding well all week. Laboratory tests in our department, including a complete blood count with differential and inflammatory markers, were all normal. Repeat x-rays showed a subtle distal tibial lucency, initially overlooked. The infant was admitted to the hospital and received a magnetic resonance imaging,which demonstrated distal tibial osteomyelitis with an accompanying ankle effusion. Cultures from the bone grew group B Streptococcus, and the infant received 6 weeks of antibiotic therapy. PMID:26341810

  9. Moving forward: cystic fibrosis gene therapy.

    PubMed

    Griesenbach, Uta; Alton, Eric W F W

    2013-10-15

    Since cloning of the CFTR gene more than 20 years ago a large number of pre-clinical and clinical CF gene therapy studies have been performed and a vast amount of information and know-how has been generated. Here, we will review key studies with a particular emphasis on clinical findings. We have learnt that the lung is a more difficult target than originally anticipated, and we describe the strength and weaknesses of the most commonly used airway gene transfer agents (GTAs). In our view, one of the most significant developments in recent years is the generation of lentiviral vectors, which efficiently transduce lung tissue. However, focused and co-ordinated efforts assessing lentiviral vector safety and scaling up of production will be required to move this vector into clinical lung gene therapy studies. PMID:23918661

  10. Moving Granular Bed Filter Development Program

    SciTech Connect

    Wilson, K.B.; Haas, J.C.; Gupta, R.P.; Turk, B.S.

    1996-12-31

    For coal-fired power plants utilizing a gas turbine, the removal of ash particles is necessary to protect the turbine and to meet emission standards. Advantages are also evident for a filter system that can remove other coal-derived contaminants such as alkali, halogens, and ammonia. With most particulates and other contaminants removed, erosion and corrosion of turbine materials, as well as deposition of particles within the turbine, are reduced to acceptable levels. The granular bed filter is suitable for this task in a pressurized gasification or combustion environment. The objective of the base contract was to develop conceptual designs of moving granular bed filter (GBF) and ceramic candle filter technologies for control of particles from integrated gasification combined cycle (IGCC), pressurized fluidized-bed combustion (PFBC), and direct coal-fueled turbine (DCFT) systems. The results of this study showed that the GBF design compared favorably with the candle filter. Three program options followed the base contract. The objective of Option I, Component Testing, was to identify and resolve technical issues regarding GBF development for IGCC and PFBC environments. This program was recently completed. The objective of Option II, Filter Proof Tests, is to test and evaluate the moving GBF system at a government-furnished hot-gas cleanup test facility. This facility is located at Southern Company Services (SCS), Inc., Wilsonville, Alabama. The objective of Option III, Multicontaminant Control Using a GBF, is to develop a chemically reactive filter material that will remove particulates plus one or more of the following coal-derived contaminants: alkali, halogens, and ammonia.

  11. Probe Without Moving Parts Measures Flow Angle

    NASA Technical Reports Server (NTRS)

    Corda, Stephen; Vachon, M. Jake

    2003-01-01

    The measurement of local flow angle is critical in many fluid-dynamic applications, including the aerodynamic flight testing of new aircraft and flight systems. Flight researchers at NASA Dryden Flight Research Center have recently developed, flight-tested, and patented the force-based flow-angle probe (FLAP), a novel, force-based instrument for the measurement of local flow direction. Containing no moving parts, the FLAP may provide greater simplicity, improved accuracy, and increased measurement access, relative to conventional moving vane-type flow-angle probes. Forces in the FLAP can be measured by various techniques, including those that involve conventional strain gauges (based on electrical resistance) and those that involve more advanced strain gauges (based on optical fibers). A correlation is used to convert force-measurement data to the local flow angle. The use of fiber optics will enable the construction of a miniature FLAP, leading to the possibility of flow measurement in very small or confined regions. This may also enable the tufting of a surface with miniature FLAPs, capable of quantitative flow-angle measurements, similar to attaching yarn tufts for qualitative measurements. The prototype FLAP was a small, aerodynamically shaped, low-aspect-ratio fin about 2 in. (approximately equal to 5 cm) long, 1 in. (approximately equal to 2.5 cm) wide, and 0.125 in. (approximately equal to 0.3 cm) thick (see Figure 1). The prototype FLAP included simple electrical-resistance strain gauges for measuring forces. Four strain gauges were mounted on the FLAP; two on the upper surface and two on the lower surface. The gauges were connected to form a full Wheatstone bridge, configured as a bending bridge. In preparation for a flight test, the prototype FLAP was mounted on the airdata boom of a flight-test fixture (FTF) on the NASA Dryden F-15B flight research airplane.

  12. Moving Towards Domain Wall Devices in Ferroics

    NASA Astrophysics Data System (ADS)

    Gregg, Marty

    Domain walls in ferroelectric, ferroelastic and multiferroic oxides are distinct functional materials in their own right. They can be conducting, or even superconducting, when surrounding domains are insulating; they can demonstrate magnetism when the surrounding bulk is non-magnetic and they can contain ordered electrical dipoles when the matrix containing them is non-polar. Since domain walls can also be created, destroyed, and controllably moved from place to place, there is an amazing opportunity for us to design new forms of devices in which functionality is actively and dynamically deployed (now you see it; now you don't). This is the essence of the emerging field known as ``domain wall nanoelectronics''. In time, this arena of research could change the way we think of nanoscale functional devices, moving increasingly towards agile circuitry and neuromorphic device architectures. While the control of domain wall injection, movement and annihilation has been developed rather well in the nanomagnetics community (in race-track and domain wall logic research), similar research has not been widely performed in nanoscale ferroelectrics, ferroelastics and multiferroics. This talk will discuss progress that has been made to date and the way in which nanomagnetics research can be used as a source of inspiration. Site-specific domain wall injection and motion control in both proper and improper ferroelectrics using inhomogeneous electric and elastic fields, as well as dielectric patterning in uniaxial ferroelectrics, will be specifically considered. As will be shown, sufficient control has been developed to allow the creation of a diode for domain wall motion in ferroelectrics, for example. The author acknowledges support from the Engineering and Physical Sciences Research Council (EPSRC).

  13. Editorial commentary revisited and the spin move refined.

    PubMed

    Lubowitz, James H; Provencher, Matthew T; Brand, Jefferson C; Rossi, Michael J

    2015-04-01

    First, editorial commentary: editorial commentary may be educational and may be controversial, but above all else, authors come first. Second, The Spin Move: The Spin Move is effective, cost-effective, and ubiquitous because, while many techniques are specific to a single joint, The Spin Move can be performed as a part of any arthroscopic and related procedure. However, like many advanced procedures, The Spin Move, when poorly executed, entails substantial risk. Preoperative planning is essential, and The Spin Move must be reviewed by inexperienced practitioners, in detailed text, figures tables, and video, at www.arthroscopytechniques.org. Practice makes perfect. PMID:25842226

  14. [Moving Mirror Scanning System Based on the Flexible Hinge Support].

    PubMed

    Xie, Fei; Feng, Fei; Wang, Fu-bei; Wu, Qiong-shui; Zeng, Li-bo

    2015-08-01

    In order to improve moving mirror drive of Fourier transform infrared spectrometer, we design a dynamic scanning system based on flexible hinge support. Using the flexible hinge support way and the voice coil motor drive mode. Specifically, Using right Angle with high accuracy high stability type flexible hinge support mechanism support moving mirror, dynamic mirror can be moved forward and backward driven by voice coil motor reciprocating motion, DSP control system to control the moving mirror at a constant speed. The experimental results show that the designed of moving mirror scanning system has advantages of stability direction, speed stability, superior seismic performance. PMID:26672322

  15. An effective algorithm for radar dim moving target detection

    NASA Astrophysics Data System (ADS)

    Luo, Qian; Wang, Yanfei

    2009-10-01

    The detection and tracking of dim moving targets in very low signal-to-noise ratio (SNR) environment has been a difficult problem in radar signal processing. For low SNR moving targets detection, a new improved dynamic programming algorithm based on track-before-detection method is presented. This new algorithm integrates energy along target moving tracks according to target moving parameter information. This process substitutes the exhaustive search by a feasible algorithm. The simulation confirms that this algorithm, with high computational efficiency, is feasible, and can effectively estimate trajectories of dim closing moving targets. The process has also been shown to give an increase in detection.

  16. Phylogenetic and environmental diversity of DsrAB-type dissimilatory (bi)sulfite reductases

    PubMed Central

    Müller, Albert Leopold; Kjeldsen, Kasper Urup; Rattei, Thomas; Pester, Michael; Loy, Alexander

    2015-01-01

    The energy metabolism of essential microbial guilds in the biogeochemical sulfur cycle is based on a DsrAB-type dissimilatory (bi)sulfite reductase that either catalyzes the reduction of sulfite to sulfide during anaerobic respiration of sulfate, sulfite and organosulfonates, or acts in reverse during sulfur oxidation. Common use of dsrAB as a functional marker showed that dsrAB richness in many environments is dominated by novel sequence variants and collectively represents an extensive, largely uncharted sequence assemblage. Here, we established a comprehensive, manually curated dsrAB/DsrAB database and used it to categorize the known dsrAB diversity, reanalyze the evolutionary history of dsrAB and evaluate the coverage of published dsrAB-targeted primers. Based on a DsrAB consensus phylogeny, we introduce an operational classification system for environmental dsrAB sequences that integrates established taxonomic groups with operational taxonomic units (OTUs) at multiple phylogenetic levels, ranging from DsrAB enzyme families that reflect reductive or oxidative DsrAB types of bacterial or archaeal origin, superclusters, uncultured family-level lineages to species-level OTUs. Environmental dsrAB sequences constituted at least 13 stable family-level lineages without any cultivated representatives, suggesting that major taxa of sulfite/sulfate-reducing microorganisms have not yet been identified. Three of these uncultured lineages occur mainly in marine environments, while specific habitat preferences are not evident for members of the other 10 uncultured lineages. In summary, our publically available dsrAB/DsrAB database, the phylogenetic framework, the multilevel classification system and a set of recommended primers provide a necessary foundation for large-scale dsrAB ecology studies with next-generation sequencing methods. PMID:25343514

  17. Myxobacteria: Moving, Killing, Feeding, and Surviving Together

    PubMed Central

    Muñoz-Dorado, José; Marcos-Torres, Francisco J.; García-Bravo, Elena; Moraleda-Muñoz, Aurelio; Pérez, Juana

    2016-01-01

    Myxococcus xanthus, like other myxobacteria, is a social bacterium that moves and feeds cooperatively in predatory groups. On surfaces, rod-shaped vegetative cells move in search of the prey in a coordinated manner, forming dynamic multicellular groups referred to as swarms. Within the swarms, cells interact with one another and use two separate locomotion systems. Adventurous motility, which drives the movement of individual cells, is associated with the secretion of slime that forms trails at the leading edge of the swarms. It has been proposed that cellular traffic along these trails contributes to M. xanthus social behavior via stigmergic regulation. However, most of the cells travel in groups by using social motility, which is cell contact-dependent and requires a large number of individuals. Exopolysaccharides and the retraction of type IV pili at alternate poles of the cells are the engines associated with social motility. When the swarms encounter prey, the population of M. xanthus lyses and takes up nutrients from nearby cells. This cooperative and highly density-dependent feeding behavior has the advantage that the pool of hydrolytic enzymes and other secondary metabolites secreted by the entire group is shared by the community to optimize the use of the degradation products. This multicellular behavior is especially observed in the absence of nutrients. In this condition, M. xanthus swarms have the ability to organize the gliding movements of 1000s of rods, synchronizing rippling waves of oscillating cells, to form macroscopic fruiting bodies, with three subpopulations of cells showing division of labor. A small fraction of cells either develop into resistant myxospores or remain as peripheral rods, while the majority of cells die, probably to provide nutrients to allow aggregation and spore differentiation. Sporulation within multicellular fruiting bodies has the benefit of enabling survival in hostile environments, and increases germination and growth

  18. Image quality evaluation using moving targets

    NASA Astrophysics Data System (ADS)

    Artmann, Uwe

    2013-03-01

    The basic concept of testing a digital imaging device is to reproduce a known target and to analyze the resulting image. This semi-reference approach can be used for various different aspects of image quality. Each part of the imaging chain can have an influence on the results: lens, sensor, image processing and the target itself. The results are valid only for the complete system. If we want to test a single component, we have to make sure that we change only one and keep all others constant. When testing mobile imaging devices, we run into the problem that hardly anything can be manually controlled by the tester. Manual exposure control is not available for most devices, the focus cannot be influenced and hardly any settings for the image processing are available. Due to the limitations in the hardware, the image pipeline in the digital signal processor (DSP) of mobile imaging devices is a critical part of the image quality evaluation. The processing power of the DSPs allows sharpening, tonal correction and noise reduction to be non-linear and adaptive. This makes it very hard to describe the behavior for an objective image quality evaluation. The image quality is highly influenced by the signal processing for noise and resolution and the processing is the main reason for the loss of low contrast, _ne details, the so called texture blur. We present our experience to describe the image processing in more detail. All standardized test methods use a defined chart and require, that the chart and the camera are not moved in any way during test. In this paper, we present our results investigating the influence of chart movement during the test. Different structures, optimized for different aspects of image quality evaluation, are moved with a defined speed during the capturing process. The chart movement will change the input for the signal processing depending on the speed of the target during the test. The basic theoretical changes in the image will be the

  19. CIRCULATING MOVING BED COMBUSTION PROOF OF CONCEPT

    SciTech Connect

    Jukkola, Glen

    2010-06-30

    Circulating Moving Bed (CMB) combustion technology has its roots in traditional circulating fluidized bed technology and involves a novel method of solid fuel combustion and heat transfer. CMB technology represents a step change in improved performance and cost relative to conventional PC and FBC boilers. The CMB heat exchanger preheats the energy cycle working fluid, steam or air, to the high temperature levels required in systems for advanced power generation. Unique features of the CMB are the reduction of the heat transfer surfaces by about 60% as a result of the enhanced heat transfer rates, flexibility of operation, and about 30% lower cost over existing technology. The CMB Phase I project ran from July 2001 through March 2003. Its objective was to continue development of the CMB technology with a series of proof of concept tests. The tests were conducted at a scale that provided design data for scale up to a demonstration plant. These objectives were met by conducting a series of experiments in ALSTOM Power’s Multi-use Test Facility (MTF). The MTF was modified to operate under CMB conditions of commercial interest. The objective of the tests were to evaluate gas-to-solids heat transfer in the upper furnace, assess agglomeration in the high temperature CMB bubbling bed, and evaluate solids-to-tube heat transfer in the moving bed heat exchanger. The Phase I program results showed that there are still some significant technical uncertainties that needed to be resolved before the technology can be confidently scaled up for a successful demonstration plant design. Work remained in three primary areas: • scale up of gas to solid heat transfer • high temperature finned surface design • the overall requirements of mechanical and process design. The CMB Phase II workscope built upon the results of Phase I and specifically addressed the remaining technical uncertainties. It included a scaled MTF heat transfer test to provide the necessary data to scale up gas

  20. Myxobacteria: Moving, Killing, Feeding, and Surviving Together.

    PubMed

    Muñoz-Dorado, José; Marcos-Torres, Francisco J; García-Bravo, Elena; Moraleda-Muñoz, Aurelio; Pérez, Juana

    2016-01-01

    Myxococcus xanthus, like other myxobacteria, is a social bacterium that moves and feeds cooperatively in predatory groups. On surfaces, rod-shaped vegetative cells move in search of the prey in a coordinated manner, forming dynamic multicellular groups referred to as swarms. Within the swarms, cells interact with one another and use two separate locomotion systems. Adventurous motility, which drives the movement of individual cells, is associated with the secretion of slime that forms trails at the leading edge of the swarms. It has been proposed that cellular traffic along these trails contributes to M. xanthus social behavior via stigmergic regulation. However, most of the cells travel in groups by using social motility, which is cell contact-dependent and requires a large number of individuals. Exopolysaccharides and the retraction of type IV pili at alternate poles of the cells are the engines associated with social motility. When the swarms encounter prey, the population of M. xanthus lyses and takes up nutrients from nearby cells. This cooperative and highly density-dependent feeding behavior has the advantage that the pool of hydrolytic enzymes and other secondary metabolites secreted by the entire group is shared by the community to optimize the use of the degradation products. This multicellular behavior is especially observed in the absence of nutrients. In this condition, M. xanthus swarms have the ability to organize the gliding movements of 1000s of rods, synchronizing rippling waves of oscillating cells, to form macroscopic fruiting bodies, with three subpopulations of cells showing division of labor. A small fraction of cells either develop into resistant myxospores or remain as peripheral rods, while the majority of cells die, probably to provide nutrients to allow aggregation and spore differentiation. Sporulation within multicellular fruiting bodies has the benefit of enabling survival in hostile environments, and increases germination and growth

  1. Spin-orbit effect on the magnetic shielding constant using the ab initio UHF method: tin tetrahalides

    NASA Astrophysics Data System (ADS)

    Kaneko, H.; Hada, M.; Nakajima, T.; Nakatsuji, H.

    1996-10-01

    The 119Sn NMR chemical shifts of SnX 4(X=H, Cl, Br and I) and SnBr 4- nI n ( n = 1, 2, 3) are calculated by the ab initio UHF method including the spin-orbit (SO) interaction combined with the finite perturbation method. The calculated Sn chemical shifts are in good agreement with experiment when the SO interaction is included. As the halogen ligand becomes heavier, the SO effect increases and the chemical shift moves to a higher field. The normal halogen dependence by the substitution from Cl to I in tin tetrahalides is reproduced only when the SO interaction is included. The origin of the SO effect is ascribed to the Fermi contact term.

  2. Plans, Patterns, and Move Categories Guiding a Highly Selective Search

    NASA Astrophysics Data System (ADS)

    Trippen, Gerhard

    In this paper we present our ideas for an Arimaa-playing program (also called a bot) that uses plans and pattern matching to guide a highly selective search. We restrict move generation to moves in certain move categories to reduce the number of moves considered by the bot significantly. Arimaa is a modern board game that can be played with a standard Chess set. However, the rules of the game are not at all like those of Chess. Furthermore, Arimaa was designed to be as simple and intuitive as possible for humans, yet challenging for computers. While all established Arimaa bots use alpha-beta search with a variety of pruning techniques and other heuristics ending in an extensive positional leaf node evaluation, our new bot, Rat, starts with a positional evaluation of the current position. Based on features found in the current position - supported by pattern matching using a directed position graph - our bot Rat decides which of a given set of plans to follow. The plan then dictates what types of moves can be chosen. This is another major difference from bots that generate "all" possible moves for a particular position. Rat is only allowed to generate moves that belong to certain categories. Leaf nodes are evaluated only by a straightforward material evaluation to help avoid moves that lose material. This highly selective search looks, on average, at only 5 moves out of 5,000 to over 40,000 possible moves in a middle game position.

  3. Ab initio study of basal slip in Nb(2)AlC.

    PubMed

    Music, Denis; Sun, Zhimei; Voevodin, Andrey A; Schneider, Jochen M

    2006-05-01

    Using ab initio calculations, we have studied shearing in Nb(2)AlC, where NbC and Al layers are interleaved. The stress-strain analysis of this deformation mode reveals Nb-Al bond breaking, while the Nb-C bond length decreases by 4.1%. Furthermore, there is no evidence for phase transformation during deformation. This is consistent with basal slip and may be understood on the basis of the electronic structure: bands below the Fermi level are responsible for the dd bonding between NbC basal planes and only a single band with a weak dd interaction is not resistant to shearing, while all other bands are unaffected. The Al-Nb bonding character can be described as mainly metallic with weak covalent-ionic contributions. Our study demonstrates that Al layers move with relative ease under shear strain. Phase conservation upon shearing is unusual for carbides and may be due to the layered nature of the phase studied. Here, we describe the electronic origin of basal slip in Nb(2)AlC, the atomic mechanism which enables reversible plasticity in this class of materials. PMID:21690790

  4. Nitrification in a vertically moving biofilm system.

    PubMed

    Rodgers, M; Healy, M G; Prendergast, J

    2006-05-01

    A laboratory continuous feed biofilm reactor, comprising a bulk fluid reactor, a biofilm plastic module, a feed tank, and pneumatic devices and controls, was operated for a total period of 257 days, including seeding time, to treat domestic-strength synthetic wastewater under increasing ammonium nitrogen (NH(4)(+)--N) loading rates, ranging from 0.17+/-0.01 (0.71+/-0.06 gm(-2)d(-1)) to 0.70+/-0.02 kgm(-3)d(-1) (2.9+/-0.1 gm(-2)d(-1)). The biofilm plastic module was moved vertically in and out of the wastewater in continuous cycles. The maximum NH(4)(+)-N removal rate was reached during the maximum loading phase, when a NH(4)(+)--N loading rate of 0.70+/-0.02 kgm(-3)d(-1) (2.9+/-0.1 gm(-2)d(-1)) was applied to the system. During this loading period, the average NH(4)(+)--N removal rate was 0.30+/-0.10 kgm(-3)d(-1) (1.30+/-0.40 gm(-2)d(-1)). PMID:16182437

  5. Mass Transfer Enhancement in Moving Biofilm Structures

    PubMed Central

    Taherzadeh, Danial; Picioreanu, Cristian; Horn, Harald

    2012-01-01

    Biofilms are layers of microbial cells growing on an interface and they can form highly complex structures adapted to a wide variety of environmental conditions. Biofilm streamers have a small immobile base attached to the support and a flexible tail elongated in the flow direction, which can vibrate in fast flows. Herein we report numerical results for the role of the periodical movement of biofilm streamers on the nutrient uptake and in general on the solute mass transfer enhancement due to flow-induced oscillations. We developed what to our knowledge is a novel two-dimensional fluid-structure interaction model coupled to unsteady solute mass transport and solved the model using the finite element method with a moving mesh. Results demonstrate that the oscillatory movement of the biofilm tail significantly increases the substrate uptake. The mass transfer coefficient is the highest in regions close to the streamer tip. The reason for substrate transfer enhancement is the increase in speed of tip movement relative to the surrounding liquid, thereby reducing the thickness of the mass transfer boundary layer. In addition, we show that the relative mass transfer enhancement in unsteady conditions compared with the rigid static structure is larger at higher flow velocities, and this relative increase favors a more flexible structure. PMID:22500748

  6. The Micromechanics of the Moving Contact Line

    NASA Technical Reports Server (NTRS)

    Lichter, Seth

    1999-01-01

    A transient moving contact line is investigated experimentally. The dynamic interface shape between 20 and 800 microns from the contact line is compared with theory. A novel experiment is devised, in which the contact line is set into motion by electrically altering the solid-liquid surface tension gamma(sub SL). The contact line motion simulates that of spontaneous wetting along a vertical plate with a maximum capillary number Ca approx. = 4 x 10(exp -2). The images of the dynamic meniscus are analyzed as a funtion of Ca. For comparison, the steady-state hydrodynamic equation based on the creeping flow model in a wedge geometry and the three-region uniform perturbation expansion of Cox (1986) is adopted. The interface shape is well depicted by the uniform solutions for Ca <= 10(exp -3). However, for Ca > 10(exp -3), the uniform solution over-predicts the viscous bending. This over-prediction can be accounted for by modifying the slip coefficient within the intermediate solution. With this correction, the measured interface shape is seen to match the theoretical prediction for all capillary numbers. The amount of slip needed to fit the measurements does not scale with the capillary number.

  7. Quantification of moving target cyber defenses

    NASA Astrophysics Data System (ADS)

    Farris, Katheryn A.; Cybenko, George

    2015-05-01

    Current network and information systems are static, making it simple for attackers to maintain an advantage. Adaptive defenses, such as Moving Target Defenses (MTD) have been developed as potential "game-changers" in an effort to increase the attacker's workload. With many new methods being developed, it is difficult to accurately quantify and compare their overall costs and effectiveness. This paper compares the tradeoffs between current approaches to the quantification of MTDs. We present results from an expert opinion survey on quantifying the overall effectiveness, upfront and operating costs of a select set of MTD techniques. We find that gathering informed scientific opinions can be advantageous for evaluating such new technologies as it offers a more comprehensive assessment. We end by presenting a coarse ordering of a set of MTD techniques from most to least dominant. We found that seven out of 23 methods rank as the more dominant techniques. Five of which are techniques of either address space layout randomization or instruction set randomization. The remaining two techniques are applicable to software and computer platforms. Among the techniques that performed the worst are those primarily aimed at network randomization.

  8. Instrumental aspects of Simulated Moving Bed chromatography.

    PubMed

    Faria, Rui P V; Rodrigues, Alírio E

    2015-11-20

    The Simulated Moving Bed (SMB) is one of the greatest illustrations of the potential of continuous multicolumn counter-current chromatographic processes. Although it was initially developed for the purification of petrochemicals, the advances that this technology has experienced during more than 50 years of existence were at the basis of its successful expansion into the food and pharmaceuticals industries. In this context, the present work provides an overview of the evolution of SMB focused on the most relevant instrumental aspects related with this technology. For that purpose, the details of the design and construction of this equipment will be reviewed, with special attention to the valves design. Due to its increasing interest, the technical requirements imposed by unconventional operating modes will be addressed together with the design adaptations that allow the operation of SMB units with compressible fluids and the implementation of Hybrid-SMB processes. Finally, as SMB technology has been unable to meet all the process specifications within the growing biopharmaceuticals industry, the development of alternative multicolumn counter-current units has intensified over the last few years. Hence, examples of the design and application of these new units will be provided. PMID:26341597

  9. Moving through a multiplex holographic scene

    NASA Astrophysics Data System (ADS)

    Mrongovius, Martina

    2013-02-01

    This paper explores how movement can be used as a compositional element in installations of multiplex holograms. My holographic images are created from montages of hand-held video and photo-sequences. These spatially dynamic compositions are visually complex but anchored to landmarks and hints of the capturing process - such as the appearance of the photographer's shadow - to establish a sense of connection to the holographic scene. Moving around in front of the hologram, the viewer animates the holographic scene. A perception of motion then results from the viewer's bodily awareness of physical motion and the visual reading of dynamics within the scene or movement of perspective through a virtual suggestion of space. By linking and transforming the physical motion of the viewer with the visual animation, the viewer's bodily awareness - including proprioception, balance and orientation - play into the holographic composition. How multiplex holography can be a tool for exploring coupled, cross-referenced and transformed perceptions of movement is demonstrated with a number of holographic image installations. Through this process I expanded my creative composition practice to consider how dynamic and spatial scenes can be conveyed through the fragmented view of a multiplex hologram. This body of work was developed through an installation art practice and was the basis of my recently completed doctoral thesis: 'The Emergent Holographic Scene — compositions of movement and affect using multiplex holographic images'.

  10. Schlieren system and method for moving objects

    NASA Technical Reports Server (NTRS)

    Weinstein, Leonard M. (Inventor)

    1996-01-01

    A system and method are provided for recording density changes in a flow field surrounding a moving object. A mask having an aperture for regulating the passage of images therethrough is placed in front of an image recording medium. An optical system is placed in front of the mask. A transition having a light field-of-view and a dark field-of-view is located beyond the test object. The optical system focuses an image of the transition at the mask such that the aperture causes a band of light to be defined on the image recording medium. The optical system further focuses an image of the object through the aperture of the mask so that the image of the object appears on the image recording medium. Relative motion is minimized between the mask and the transition. Relative motion is also minimized between the image recording medium and the image of the object. In this way, the image of the object and density changes in a flow field surrounding the object are recorded on the image recording medium when the object crosses the transition in front of the optical system.

  11. Generalized dynamics of moving dislocations in quasicrystals

    NASA Astrophysics Data System (ADS)

    Agiasofitou, Eleni; Lazar, Markus; Kirchner, Helmut

    2010-12-01

    A theoretical framework for dislocation dynamics in quasicrystals is provided according to the continuum theory of dislocations. Firstly, we present the fundamental theory for moving dislocations in quasicrystals giving the dislocation density tensors and introducing the dislocation current tensors for the phonon and phason fields, including the Bianchi identities. Next, we give the equations of motion for the incompatible elastodynamics as well as for the incompatible elasto-hydrodynamics of quasicrystals. We continue with the derivation of the balance law of pseudomomentum thereby obtaining the generalized forms of the Eshelby stress tensor, the pseudomomentum vector, the dynamical Peach-Koehler force density and the Cherepanov force density for quasicrystals. The form of the dynamical Peach-Koehler force for a straight dislocation is obtained as well. Moreover, we deduce the balance law of energy that gives rise to the generalized forms of the field intensity vector and the elastic power density of quasicrystals. The above balance laws are produced for both models. The differences between the two models and their consequences are revealed. The influences of the phason fields as well as of the dynamical terms are also discussed.

  12. SEEDS Moving Groups and CHARIS Status Updates

    NASA Technical Reports Server (NTRS)

    McElwain, Michael

    2012-01-01

    We present the status update for the SEEDS Moving Groups category. To date, we have observed 59 targets and currently have more than 20 candidates. We also present the expected scientific capabilities of CHARIS, the Coronagraphic High Angular Resolution Imaging Spectrograph, which is being built for the Subaru 8.2 m telescope of the National Astronomical Observatory of Japan. CHARIS will be implemented behind the new extreme adaptive optics system at Subaru, SCExAO, and the existing 188-actuator system AO188. CHARIS will offer three observing modes over nearinfrared wavelengths from 0.9 to 2.4 microns (the y-, J-, H-, and K-bands), including a low-spectral-resolution mode covering this entire wavelength range and a high-resolution mode within a single band. With these capabilities, CHARIS will offer exceptional sensitivity for discovering giant exoplanets, and will enable detailed characterization of their atmospheres, CHARIS, the only planned high-contrast integral field spectrograph on an 8m-class telescope in the Northern Hemisphere, will complement the similar instruments such as Project 1640 at Palomar, and GPI and SPHERE in Chile.

  13. Generalized dynamics of moving dislocations in quasicrystals.

    PubMed

    Agiasofitou, Eleni; Lazar, Markus; Kirchner, Helmut

    2010-12-15

    A theoretical framework for dislocation dynamics in quasicrystals is provided according to the continuum theory of dislocations. Firstly, we present the fundamental theory for moving dislocations in quasicrystals giving the dislocation density tensors and introducing the dislocation current tensors for the phonon and phason fields, including the Bianchi identities. Next, we give the equations of motion for the incompatible elastodynamics as well as for the incompatible elasto-hydrodynamics of quasicrystals. We continue with the derivation of the balance law of pseudomomentum thereby obtaining the generalized forms of the Eshelby stress tensor, the pseudomomentum vector, the dynamical Peach-Koehler force density and the Cherepanov force density for quasicrystals. The form of the dynamical Peach-Koehler force for a straight dislocation is obtained as well. Moreover, we deduce the balance law of energy that gives rise to the generalized forms of the field intensity vector and the elastic power density of quasicrystals. The above balance laws are produced for both models. The differences between the two models and their consequences are revealed. The influences of the phason fields as well as of the dynamical terms are also discussed. PMID:21406784

  14. Pan-STARRS Moving Object Processing System

    NASA Astrophysics Data System (ADS)

    Jedicke, R.; Denneau, L.; Grav, T.; Heasley, J.; Kubica, Jeremy; Pan-STARRS Team

    2005-12-01

    The Institute for Astronomy at the University of Hawaii is developing a large optical astronomical surveying system - the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS). The Moving Object Processing System (MOPS) client of the Pan-STARRS image processing pipeline is developing software to automatically discover and identify >90% of near-Earth objects (NEOs) 300m in diameter and >80% of other classes of asteroids and comets. In developing its software, MOPS has created a synthetic solar system model (SSM) with over 10 million objects whose distributions of orbital characteristics matches those expected for objects that Pan-STARRS will observe. MOPS verifies its correct operation by simulating the survey and subsequent discovery of synthetically generated objects. MOPS also employs novel techniques in handling the computationally difficult problem of linking large numbers of unknown asteroids in a field of detections. We will describe the creation and verification of the Pan-STARRS MOPS SSM, demonstrate synthetic detections and observations by the MOPS, describe the MOPS asteroid linking techniques, describe accuracy and throughput of the entire MOPS system, and provide predictions regarding the numbers and kinds of objects, including as yet undiscovered "extreme objects", that the MOPS expects to find over its 10-year lifetime. Pan-STARRS is funded under a grant from the U.S. Air Force.

  15. Analysis of SAR moving grid processing for focusing and detection of ground moving targets

    NASA Astrophysics Data System (ADS)

    Hack, Daniel E.; Saville, Michael A.

    2011-06-01

    This paper investigates the performance of single-channel SAR-GMTI systems in the focusing and detection of translating ground targets moving in the presence of a clutter background. Specifically, focusing and detection performance is investigated by applying the Moving Grid Processing (MGP) focusing technique to a scene containing an accelerating target moving in the presence of both uniform and correlated K-distributed clutter backgrounds. The increase in detection sensitivity resulting from the focusing operation is found to result from two separable effects, target focusing and clutter defocusing. While the detection sensitivity gain due to target focusing is common for both clutter types, the gain due to clutter defocusing is found to be significantly greater for textured clutter than for uniform clutter, by approximately 5 to 6 dB in the simulated scenario under consideration. This paper concludes with a discussion of the phenomenological causes for this difference and implications of this finding for single channel SAR-GMTI systems operating in heterogeneous clutter environments.

  16. Ab-initio calculations on melting of thorium

    NASA Astrophysics Data System (ADS)

    Mukherjee, D.; Sahoo, B. D.; Joshi, K. D.; Kaushik, T. C.; Gupta, Satish C.

    2016-05-01

    Ab-initio molecular dynamics study has been performed on face centered cubic structured thorium to determine its melting temperature at room pressure. The ion-electron interaction potential energy calculated as a function of temperature for three volumes (a0)3 and (1.02a0)3 and (1.04a0)3 increases gradually with temperature and undergoes a sharp jump at ~2200 K, ~2100 K and ~1800 K, respectively. Here, a0 = 5.043 Å is the equilibrium lattice parameter at 0 K obtained from ab-initio calculations. These jumps in interaction energy are treated as due to the onset of melting and corresponding temperatures as melting point. The melting point of 2100 K is close to the experimental value of 2023K. Further, the same has been verified by plotting the atomic arrangement evolved at various temperatures and corresponding pair correlation functions.

  17. Ab initio molecular dynamics: concepts, recent developments, and future trends.

    PubMed

    Iftimie, Radu; Minary, Peter; Tuckerman, Mark E

    2005-05-10

    The methodology of ab initio molecular dynamics, wherein finite-temperature dynamical trajectories are generated by using forces computed "on the fly" from electronic structure calculations, has had a profound influence in modern theoretical research. Ab initio molecular dynamics allows chemical processes in condensed phases to be studied in an accurate and unbiased manner, leading to new paradigms in the elucidation of microscopic mechanisms, rationalization of experimental data, and testable predictions of new phenomena. The purpose of this work is to give a brief introduction to the technique and to review several important recent developments in the field. Several illustrative examples showing the power of the technique have been chosen. Perspectives on future directions in the field also will be given. PMID:15870204

  18. Recent progress in ab initio density matrix renormalization group methodology

    NASA Astrophysics Data System (ADS)

    Hachmann, Johannes; Dorando, Jonathan J.; Kin-Lic Chan, Garnet

    2008-03-01

    We present some recent developments in the ab initio density matrix renormalization group (DMRG) method for quantum chemical problems, in particular our local, quadratic scaling algorithm [1] for low dimensional systems. This method is particularly suited for the description of strong nondynamic correlation, and allows us to compute numerically exact (FCI) correlated energies for large active spaces, up to one order of magnitude larger then can be done by conventional CASCI techniques. Other features of this method are its inherent multireference nature, compactness, variational results, size-consistency and size-extensivity. In addition we will review the problems (predominantly organic electronic materials) on which we applied the ab initio DMRG: 1) metal-insulator transition in hydrogen chains [1] 2) all-trans polyacetylene [1] 3) acenes [2] 4) polydiacetylenes [3]. References [1] Hachmann, Cardoen, Chan, JCP 125 (2006), 144101. [2] Hachmann, Dorando, Avil'es, Chan, JCP 127 (2007), 134309. [3] unpublished.

  19. Understanding phonon transport in thermoelectric materials using ab initio approaches

    NASA Astrophysics Data System (ADS)

    Broido, David

    Good thermoelectric materials have low phonon thermal conductivity, kph. Accurate theories to describe kph are important components in developing predictive models of thermoelectric efficiency that can help guide synthesis and measurement efforts. We have developed ab initio approaches to calculate kph, in which phonon modes and phonon scattering rates are computed using interatomic force constants determined from density functional theory, and a full solution of the Boltzmann transport equation for phonons is implemented. A recent approach to calculate interatomic force constants using ab initio molecular dynamics has yielded a good description of the thermal properties of Bi2Te3. But, the complexity of new promising candidate thermoelectric materials introduces computational challenges in assessing their thermal properties. An example is germanane, a germanium based hydrogen-terminated layered semiconductor, which we will discuss in this talk.

  20. Ab Initio Calculations Of Light-Ion Reactions

    SciTech Connect

    Navratil, P; Quaglioni, S; Roth, R; Horiuchi, W

    2012-03-12

    The exact treatment of nuclei starting from the constituent nucleons and the fundamental interactions among them has been a long-standing goal in nuclear physics. In addition to the complex nature of nuclear forces, one faces the quantum-mechanical many-nucleon problem governed by an interplay between bound and continuum states. In recent years, significant progress has been made in ab initio nuclear structure and reaction calculations based on input from QCD employing Hamiltonians constructed within chiral effective field theory. In this contribution, we present one of such promising techniques capable of describing simultaneously both bound and scattering states in light nuclei. By combining the resonating-group method (RGM) with the ab initio no-core shell model (NCSM), we complement a microscopic cluster approach with the use of realistic interactions and a microscopic and consistent description of the clusters. We discuss applications to light nuclei scattering, radiative capture and fusion reactions.

  1. Spin-orbit decomposition of ab initio nuclear wave functions

    NASA Astrophysics Data System (ADS)

    Johnson, Calvin W.

    2015-03-01

    Although the modern shell-model picture of atomic nuclei is built from single-particle orbits with good total angular momentum j , leading to j -j coupling, decades ago phenomenological models suggested that a simpler picture for 0 p -shell nuclides can be realized via coupling of the total spin S and total orbital angular momentum L . I revisit this idea with large-basis, no-core shell-model calculations using modern ab initio two-body interactions and dissect the resulting wave functions into their component L - and S -components. Remarkably, there is broad agreement with calculations using the phenomenological Cohen-Kurath forces, despite a gap of nearly 50 years and six orders of magnitude in basis dimensions. I suggest that L -S decomposition may be a useful tool for analyzing ab initio wave functions of light nuclei, for example, in the case of rotational bands.

  2. Exploring complex chemical reactions by ab-initio simulation

    NASA Astrophysics Data System (ADS)

    Parrinello, Michele

    1998-03-01

    Recent progress in the ab-initio molecular dynamics method and the power of parallel computing, allow the detailed study of complex chemical reaction of great industrial relevance. We illustrate this unprecedented capability by investigating the second generation Ziegler-Natta catalytic process. In this inhomogeneous catalyst, a polymerization reaction is induced by TiCl4 molecules deposited on an MgCl2 solid support. A density functional based ab-initio molecular dynamics calculation conducted with a minimum of initial assumption allows to understand the nature of the catalytic center and to determine the reaction path with the associated free energy barrier. Furthermore our calculation can explain in a nontrivial way the stereo-selectivity of the process.

  3. Ab Initio Electronic Relaxation Times and Transport in Noble Metals

    NASA Astrophysics Data System (ADS)

    Mustafa, Jamal I.; Bernardi, Marco; Neaton, Jeffrey B.; Louie, Steven G.

    Relaxation times employed to study electron transport in metals are typically assumed to be constants and obtained empirically using the Drude model. Here, we employ ab initio calculations to compute the electron-phonon relaxation times of Cu, Ag, and Au, and find that they vary significantly on the Fermi surface, spanning ~15 -45 fs. We compute room temperature resistivities in excellent agreement with experiment by combining GW bandstructures, Wannier-interpolated band velocities, and ab initio relaxation times. Our calculations are compared to other approximations used for the relaxation times. Additionally, an importance sampling scheme is introduced to speed up the convergence of resistivity and transport calculations by sampling directly points on the Fermi surface. This work was supported by NSF Grant No. DMR15-1508412 and U.S. DOE under Contract No. DE-AC02-05CH11231. Computational resources have been provided by DOE at LBNL's NERSC facility.

  4. Ab initio Monte Carlo investigation of small lithium clusters.

    SciTech Connect

    Srinivas, S.

    1999-06-16

    Structural and thermal properties of small lithium clusters are studied using ab initio-based Monte Carlo simulations. The ab initio scheme uses a Hartree-Fock/density functional treatment of the electronic structure combined with a jump-walking Monte Carlo sampling of nuclear configurations. Structural forms of Li{sub 8} and Li{sub 9}{sup +} clusters are obtained and their thermal properties analyzed in terms of probability distributions of the cluster potential energy, average potential energy and configurational heat capacity all considered as a function of the cluster temperature. Details of the gradual evolution with temperature of the structural forms sampled are examined. Temperatures characterizing the onset of structural changes and isomer coexistence are identified for both clusters.

  5. Towards AB Initio Calculation of the Circular Dichroism of Peptides

    NASA Astrophysics Data System (ADS)

    Molteni, E.; Onida, G.; Tiana, G.

    2012-08-01

    In this work we plan to use ab initio spectroscopy calculations to compute circular dichroism (CD) spectra of peptides. CD provides information on protein secondary structure content; peptides, instead, remain difficult to address, due to their tendency to adopt multiple conformations in equilibrium. Therefore peptides are an interesting test-case for ab initio calculation of CD spectra. As a first application, we focus on the (83-92) fragment of HIV-1 protease, which is known to be involved in the folding and dimerization of this protein. As a preliminary step, we performed classical molecular dynamics (MD) simulations, in order to obtain a set of representative conformers of the peptide. Then, on some of the obtained conformations, we calculated absorption spectra at the independent particle, RPA and TDLDA levels, showing the presence of charge transfer excitations, and their influence on spectral features.

  6. Erythema Ab Igne in Three Girls with Anorexia Nervosa.

    PubMed

    Dessinioti, Clio; Katsambas, Andreas; Tzavela, Eleni; Karountzos, Vasileios; Tsitsika, Artemis K

    2016-03-01

    We present three girls with the eating disorder anorexia nervosa (AN) presenting with erythema ab igne (EAI), a benign, reticular, erythematous dermatosis caused by repeated prolonged skin exposure to mild heat. AN has been associated with abnormal peripheral vascular response to cold, vasoconstriction of the limbs, low hand blood flow, exaggerated response to cold stimuli, subnormal core temperature, and a general feeling of cold that may encourage prolonged heat exposure and induce EAI. PMID:26822102

  7. GAUSSIAN 76: An ab initio Molecular Orbital Program

    DOE R&D Accomplishments Database

    Binkley, J. S.; Whiteside, R.; Hariharan, P. C.; Seeger, R.; Hehre, W. J.; Lathan, W. A.; Newton, M. D.; Ditchfield, R.; Pople, J. A.

    1978-01-01

    Gaussian 76 is a general-purpose computer program for ab initio Hartree-Fock molecular orbital calculations. It can handle basis sets involving s, p and d-type Gaussian functions. Certain standard sets (STO-3G, 4-31G, 6-31G*, etc.) are stored internally for easy use. Closed shell (RHF) or unrestricted open shell (UHF) wave functions can be obtained. Facilities are provided for geometry optimization to potential minima and for limited potential surface scans.

  8. 77 FR 73279 - Airworthiness Directives; Saab AB, Saab Aerosystems Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-10

    ...We are adopting a new airworthiness directive (AD) for certain Saab AB, Saab Aerosystems Model 340A (SAAB/SF340A) and SAAB 340B airplanes. This AD was prompted by reports of stall events during icing conditions where the natural stall warning (buffet) was not identified. This AD requires replacing the stall warning computer (SWC) with a new SWC, which provides an artificial stall warning in......

  9. Thermochemical data for CVD modeling from ab initio calculations

    SciTech Connect

    Ho, P.; Melius, C.F.

    1993-12-31

    Ab initio electronic-structure calculations are combined with empirical bond-additivity corrections to yield thermochemical properties of gas-phase molecules. A self-consistent set of heats of formation for molecules in the Si-H, Si-H-Cl, Si-H-F, Si-N-H and Si-N-H-F systems is presented, along with preliminary values for some Si-O-C-H species.

  10. The study of molecular spectroscopy by ab initio methods

    NASA Technical Reports Server (NTRS)

    Bauschlicher, Charles W., Jr.; Langhoff, Stephen R.

    1991-01-01

    This review illustrates the potential of theory for solving spectroscopic problems. The accuracy of approximate techniques for including electron correlation have been calibrated by comparison with full configuration-interaction calculations. Examples of the application of ab initio calculations to vibrational, rotational, and electronic spectroscopy are given. It is shown that the state-averaged, complete active space self-consistent field, multireference configuration-interaction procedure provides a good approach for treating several electronic states accurately in a common molecular orbital basis.

  11. Ab Initio Nuclear Structure and Reaction Calculations for Rare Isotopes

    SciTech Connect

    Draayer, Jerry P.

    2014-09-28

    We have developed a novel ab initio symmetry-adapted no-core shell model (SA-NCSM), which has opened the intermediate-mass region for ab initio investigations, thereby providing an opportunity for first-principle symmetry-guided applications to nuclear structure and reactions for nuclear isotopes from the lightest p-shell systems to intermediate-mass nuclei. This includes short-lived proton-rich nuclei on the path of X-ray burst nucleosynthesis and rare neutron-rich isotopes to be produced by the Facility for Rare Isotope Beams (FRIB). We have provided ab initio descriptions of high accuracy for low-lying (including collectivity-driven) states of isotopes of Li, He, Be, C, O, Ne, Mg, Al, and Si, and studied related strong- and weak-interaction driven reactions that are important, in astrophysics, for further understanding stellar evolution, X-ray bursts and triggering of s, p, and rp processes, and in applied physics, for electron and neutrino-nucleus scattering experiments as well as for fusion ignition at the National Ignition Facility (NIF).

  12. Ab initio multiple cloning algorithm for quantum nonadiabatic molecular dynamics

    SciTech Connect

    Makhov, Dmitry V.; Shalashilin, Dmitrii V.; Glover, William J.; Martinez, Todd J.

    2014-08-07

    We present a new algorithm for ab initio quantum nonadiabatic molecular dynamics that combines the best features of ab initio Multiple Spawning (AIMS) and Multiconfigurational Ehrenfest (MCE) methods. In this new method, ab initio multiple cloning (AIMC), the individual trajectory basis functions (TBFs) follow Ehrenfest equations of motion (as in MCE). However, the basis set is expanded (as in AIMS) when these TBFs become sufficiently mixed, preventing prolonged evolution on an averaged potential energy surface. We refer to the expansion of the basis set as “cloning,” in analogy to the “spawning” procedure in AIMS. This synthesis of AIMS and MCE allows us to leverage the benefits of mean-field evolution during periods of strong nonadiabatic coupling while simultaneously avoiding mean-field artifacts in Ehrenfest dynamics. We explore the use of time-displaced basis sets, “trains,” as a means of expanding the basis set for little cost. We also introduce a new bra-ket averaged Taylor expansion (BAT) to approximate the necessary potential energy and nonadiabatic coupling matrix elements. The BAT approximation avoids the necessity of computing electronic structure information at intermediate points between TBFs, as is usually done in saddle-point approximations used in AIMS. The efficiency of AIMC is demonstrated on the nonradiative decay of the first excited state of ethylene. The AIMC method has been implemented within the AIMS-MOLPRO package, which was extended to include Ehrenfest basis functions.

  13. Ab Initio Study of Defect Properties in YPO4

    SciTech Connect

    Gao, Fei; Xiao, Haiyan Y.; Zhou, Yungang; Devanathan, Ramaswami; Hu, Shenyang Y.; Li, Yulan; Sun, Xin; Khaleel, Mohammad A.

    2012-03-01

    Ab initio methods based on density functional theory have been used to calculate the formation energies of intrinsic defects, including vacancies, interstitials, antisites and Frenkel pairs in YPO4 under the O-rich and Y2O3-rich, and the O-rich and Y-rich conditions. The larger size of the yttrium atom may give rise to higher formation energy of the phosphorus antisite defect. In general, the formation energies of anion interstitials are much smaller than those of cation interstitials for both conditions considered. It is of greatly interest to find that the relative stabilities among the same types of interstitials are independent of the reference states. The most stable configuration for oxygen interstitials is an O-O split interstitial near the Ta site, while the most stable configuration for cation interstitials is a tetrahedral interstitial near the Ta site. The cation split interstitials are unfavorable in YPO4, with much higher formation energies. Furthermore, the properties of Frenkel pairs are compared with those calculated using empirical potentials. The results reveal that both ab initio and empirical potential calculations show a similar trend in the formation energies of Frenkel pairs, but the formation energies obtained by empirical potentials are much larger than those calculated by ab initio method.

  14. Ab initio multiple cloning algorithm for quantum nonadiabatic molecular dynamics

    NASA Astrophysics Data System (ADS)

    Makhov, Dmitry V.; Glover, William J.; Martinez, Todd J.; Shalashilin, Dmitrii V.

    2014-08-01

    We present a new algorithm for ab initio quantum nonadiabatic molecular dynamics that combines the best features of ab initio Multiple Spawning (AIMS) and Multiconfigurational Ehrenfest (MCE) methods. In this new method, ab initio multiple cloning (AIMC), the individual trajectory basis functions (TBFs) follow Ehrenfest equations of motion (as in MCE). However, the basis set is expanded (as in AIMS) when these TBFs become sufficiently mixed, preventing prolonged evolution on an averaged potential energy surface. We refer to the expansion of the basis set as "cloning," in analogy to the "spawning" procedure in AIMS. This synthesis of AIMS and MCE allows us to leverage the benefits of mean-field evolution during periods of strong nonadiabatic coupling while simultaneously avoiding mean-field artifacts in Ehrenfest dynamics. We explore the use of time-displaced basis sets, "trains," as a means of expanding the basis set for little cost. We also introduce a new bra-ket averaged Taylor expansion (BAT) to approximate the necessary potential energy and nonadiabatic coupling matrix elements. The BAT approximation avoids the necessity of computing electronic structure information at intermediate points between TBFs, as is usually done in saddle-point approximations used in AIMS. The efficiency of AIMC is demonstrated on the nonradiative decay of the first excited state of ethylene. The AIMC method has been implemented within the AIMS-MOLPRO package, which was extended to include Ehrenfest basis functions.

  15. Ab initio multiple cloning algorithm for quantum nonadiabatic molecular dynamics.

    PubMed

    Makhov, Dmitry V; Glover, William J; Martinez, Todd J; Shalashilin, Dmitrii V

    2014-08-01

    We present a new algorithm for ab initio quantum nonadiabatic molecular dynamics that combines the best features of ab initio Multiple Spawning (AIMS) and Multiconfigurational Ehrenfest (MCE) methods. In this new method, ab initio multiple cloning (AIMC), the individual trajectory basis functions (TBFs) follow Ehrenfest equations of motion (as in MCE). However, the basis set is expanded (as in AIMS) when these TBFs become sufficiently mixed, preventing prolonged evolution on an averaged potential energy surface. We refer to the expansion of the basis set as "cloning," in analogy to the "spawning" procedure in AIMS. This synthesis of AIMS and MCE allows us to leverage the benefits of mean-field evolution during periods of strong nonadiabatic coupling while simultaneously avoiding mean-field artifacts in Ehrenfest dynamics. We explore the use of time-displaced basis sets, "trains," as a means of expanding the basis set for little cost. We also introduce a new bra-ket averaged Taylor expansion (BAT) to approximate the necessary potential energy and nonadiabatic coupling matrix elements. The BAT approximation avoids the necessity of computing electronic structure information at intermediate points between TBFs, as is usually done in saddle-point approximations used in AIMS. The efficiency of AIMC is demonstrated on the nonradiative decay of the first excited state of ethylene. The AIMC method has been implemented within the AIMS-MOLPRO package, which was extended to include Ehrenfest basis functions. PMID:25106573

  16. A Complete and Accurate Ab Initio Repeat Finding Algorithm.

    PubMed

    Lian, Shuaibin; Chen, Xinwu; Wang, Peng; Zhang, Xiaoli; Dai, Xianhua

    2016-03-01

    It has become clear that repetitive sequences have played multiple roles in eukaryotic genome evolution including increasing genetic diversity through mutation, changes in gene expression and facilitating generation of novel genes. However, identification of repetitive elements can be difficult in the ab initio manner. Currently, some classical ab initio tools of finding repeats have already presented and compared. The completeness and accuracy of detecting repeats of them are little pool. To this end, we proposed a new ab initio repeat finding tool, named HashRepeatFinder, which is based on hash index and word counting. Furthermore, we assessed the performances of HashRepeatFinder with other two famous tools, such as RepeatScout and Repeatfinder, in human genome data hg19. The results indicated the following three conclusions: (1) The completeness of HashRepeatFinder is the best one among these three compared tools in almost all chromosomes, especially in chr9 (8 times of RepeatScout, 10 times of Repeatfinder); (2) in terms of detecting large repeats, HashRepeatFinder also performed best in all chromosomes, especially in chr3 (24 times of RepeatScout and 250 times of Repeatfinder) and chr19 (12 times of RepeatScout and 60 times of Repeatfinder); (3) in terms of accuracy, HashRepeatFinder can merge the abundant repeats with high accuracy. PMID:26272474

  17. Ab initio calculations of reactions with light nuclei

    NASA Astrophysics Data System (ADS)

    Quaglioni, Sofia; Hupin, Guillaume; Calci, Angelo; Navrátil, Petr; Roth, Robert

    2016-03-01

    An ab initio (i.e., from first principles) theoretical framework capable of providing a unified description of the structure and low-energy reaction properties of light nuclei is desirable to further our understanding of the fundamental interactions among nucleons, and provide accurate predictions of crucial reaction rates for nuclear astrophysics, fusion-energy research, and other applications. In this contribution we review ab initio calculations for nucleon and deuterium scattering on light nuclei starting from chiral two- and three-body Hamiltonians, obtained within the framework of the ab initio no-core shell model with continuum. This is a unified approach to nuclear bound and scattering states, in which square-integrable energy eigenstates of the A-nucleon system are coupled to (A-a)+a target-plus-projectile wave functions in the spirit of the resonating group method to obtain an efficient description of the many-body nuclear dynamics both at short and medium distances and at long ranges.

  18. SPGM Moves to Building 434 This Month | Poster

    Cancer.gov

    By Ashley DeVine, Staff Writer Scientific Publications, Graphics & Media (SPGM) moves to a new location this month—Building 434. The entrance is located on Wood Street. The move will take place between Monday, February 24, and Friday, February 28. During the move, SPGM will limit disruptions to service as much as possible. A sign in front of the building will direct you to the department’s new location. Please visit SPGM in Building 434 beginning Monday, March 3.

  19. Properties of Moving Electron Bubbles in Superfluid Helium

    SciTech Connect

    Guo Wei; Maris, Humphrey J.

    2006-09-07

    It is well known that the Bernoulli effect modifies the shape of gas bubbles moving through a liquid. In this paper we investigate the influence of the Bernoulli pressure on the shape of electron bubbles moving through superfluid helium. We show that an electron bubble moving through liquid at zero pressure becomes unstable when its velocity reaches approximately 47 m s-1. In addition, the change in shape contributes significantly to the variation of the bubble mobility with velocity.

  20. Moving on: a way of life

    SciTech Connect

    Keever, C.

    1985-01-01

    In the history of ecology, Catherine Keever is a piece of the rock. Her doctoral research at Duke, published in Ecological Monographs in 1950, is a classic demonstration of some of the causes of patterns in the early stages of old field succession and has been widely referenced and reprinted over the years. Her well-known paper with Elsie Quarterman on the southern mixed hardwood forest climax of the southeastern Coastal Plain, which also appeared in Ecological Monographs (1962), remains the definitive description of this complex forest. The seeds for her delightful autobiography were planted several years ago by former colleagues at Duke, who prompted her to record some of the stories of her graduate education and her experiences in ecological research and teaching, and by younger relatives eager to learn more of the history of their family in rural North Carolina. The result is an entertaining and moving account full of homey descriptions of her youthful escapades, amusing anecdotes about her studies and teaching, and moments of sadness and triumph. The fifteen chapters tell of a life that saw much change. They begin with her childhood and her grandmother's pioneer story, follow through her long struggle for an education and her untiring efforts to continue research while teaching at small colleges, and relate her confident approach to retirement. Besides the personnel story, there are intriguing insights into the early development of ecology in the southeast. Catherine Keever's modest but highly-respected research has long been recognized s influencing ecological thought in the 1950s and 1960s. To those interested in the history of ecology, and particularly the contributions of women in the field, this book provides the unique perspective of a pioneer.

  1. Balanced Flow Meters without Moving Parts

    NASA Technical Reports Server (NTRS)

    Kelley, Anthony R.; VanBuskirk, Paul

    2008-01-01

    Balanced flow meters are recent additions to an established class of simple, rugged flow meters that contain no moving parts in contact with flow and are based on measurement of pressure drops across objects placed in flow paths. These flow meters are highly accurate, minimally intrusive, easily manufacturable, and reliable. A balanced flow meter can be easily mounted in a flow path by bolting it between conventional pipe flanges. A balanced flow meter can be used to measure the flow of any of a variety of liquids or gases, provided that it has been properly calibrated. Relative to the standard orifice-plate flow meter, the balanced flow meter introduces less turbulence and two times less permanent pressure loss and is therefore capable of offering 10 times greater accuracy and repeatability with less dissipation of energy. A secondary benefit of the reduction of turbulence is the reduction of vibration and up to 15 times less acoustic noise generation. Both the balanced flow meter and the standard orifice-plate flow meter are basically disks that contain holes and are instrumented with pressure transducers on their upstream and downstream faces. The most obvious difference between them is that the standard orifice plate contains a single, central hole while the balanced flow meter contains multiple holes. The term 'balanced' signifies that in designing the meter, the sizes and locations of the holes are determined in an optimization procedure that involves balancing of numerous factors, including volumetric flow, mass flow, dynamic pressure, kinetic energy, all in an effort to minimize such undesired effects as turbulence, pressure loss, dissipation of kinetic energy, and non-repeatability and nonlinearity of response over the anticipated range of flow conditions. Due to proper balancing of these factors, recent testing demonstrated that the balanced flow-meter performance was similar to a Venturi tube in both accuracy and pressure recovery, but featured reduced

  2. Rock Moved by Mars Lander Arm

    NASA Technical Reports Server (NTRS)

    2008-01-01

    The robotic arm on NASA's Phoenix Mars Lander slid a rock out of the way during the mission's 117th Martian day (Sept. 22, 2008) to gain access to soil that had been underneath the rock.The lander's Surface Stereo Imager took the two images for this stereo view later the same day, showing the rock, called 'Headless,' after the arm pushed it about 40 centimeters (16 inches) from its previous location.

    'The rock ended up exactly where we intended it to,' said Matt Robinson of NASA's Jet Propulsion Laboratory, robotic arm flight software lead for the Phoenix team.

    The arm had enlarged the trench near Headless two days earlier in preparation for sliding the rock into the trench. The trench was dug to about 3 centimeters (1.2 inches) deep. The ground surface between the rock's prior position and the lip of the trench had a slope of about 3 degrees downward toward the trench. Headless is about the size and shape of a VHS videotape.

    The Phoenix science team sought to move the rock in order to study the soil and the depth to subsurface ice underneath where the rock had been.

    This image was taken at about 12:30 p.m., local solar time on Mars. The view is to the north northeast of the lander.

    The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by JPL, Pasadena, Calif. Spacecraft development was by Lockheed Martin Space Systems, Denver.

  3. Diet and asthma: looking back, moving forward.

    PubMed

    Kim, June-Ho; Ellwood, Philippa E; Asher, M Innes

    2009-01-01

    approach is required to move forward and understand the complexity of the interaction of dietary factors and asthma. PMID:19519921

  4. Evaluating Moving Target Defense with PLADD

    SciTech Connect

    Jones, Stephen T.; Outkin, Alexander V.; Gearhart, Jared Lee; Hobbs, Jacob Aaron; Siirola, John Daniel; Phillips, Cynthia A.; Verzi, Stephen Joseph; Tauritz, Daniel; Mulder, Samuel A.; Naugle, Asmeret Bier

    2015-09-15

    This project evaluates the effectiveness of moving target defense (MTD) techniques using a new game we have designed, called PLADD, inspired by the game FlipIt [28]. PLADD extends FlipIt by incorporating what we believe are key MTD concepts. We have analyzed PLADD and proven the existence of a defender strategy that pushes a rational attacker out of the game, demonstrated how limited the strategies available to an attacker are in PLADD, and derived analytic expressions for the expected utility of the game’s players in multiple game variants. We have created an algorithm for finding a defender’s optimal PLADD strategy. We show that in the special case of achieving deterrence in PLADD, MTD is not always cost effective and that its optimal deployment may shift abruptly from not using MTD at all to using it as aggressively as possible. We believe our effort provides basic, fundamental insights into the use of MTD, but conclude that a truly practical analysis requires model selection and calibration based on real scenarios and empirical data. We propose several avenues for further inquiry, including (1) agents with adaptive capabilities more reflective of real world adversaries, (2) the presence of multiple, heterogeneous adversaries, (3) computational game theory-based approaches such as coevolution to allow scaling to the real world beyond the limitations of analytical analysis and classical game theory, (4) mapping the game to real-world scenarios, (5) taking player risk into account when designing a strategy (in addition to expected payoff), (6) improving our understanding of the dynamic nature of MTD-inspired games by using a martingale representation, defensive forecasting, and techniques from signal processing, and (7) using adversarial games to develop inherently resilient cyber systems.

  5. Probing Inflationary Cosmology: The Atacama B-Mode Search (ABS)

    NASA Astrophysics Data System (ADS)

    Essinger-Hileman, Thomas

    Observations of the Cosmic Microwave Background (CMB) have provided compelling evidence for the Standard Model of Cosmology and have led to the most precise estimates of cosmological parameters to date. Through its sensitivity to gravitational waves, the CMB provides a glimpse into the state of the universe just 10-35 seconds after the Big Bang and of physics on grand-unification-theory (GUT) energy scales around 1016 GeV, some 13 orders of magnitude above the energies achievable by current terrestrial particle accelerators. A gravitational-wave background (GWB) in the early universe would leave a unique, odd-parity pattern of polarization in the CMB called B modes, the magnitude of which is characterized by the tensor-to-scalar ratio, r. A GWB is generically predicted to exist by inflationary theories, and the current generation of CMB polarization experiments will probe the interesting parameter space of r < 0.05 corresponding to single-field inflationary models at GUT scales. I detail the design and construction of the Atacama B-Mode Search (ABS), which aims to measure the polarization of the CMB at degree angular scales where the primordial B-mode signal is expected to peak. ABS is a 145-GHz polarimeter that will operate from a high-altitude site in the Atacama Desert of Chile, consisting of a 60-cm crossed-Dragone telescope with cryogenic primary and secondary reflectors; an array of 240 feedhorn-coupled, transition-edge-sensor, bolometric polarimeters; and, a continuously-rotating, warm, sapphire half-wave plate (HWP) that will provide modulation of the incoming polarization of light. In this thesis, I describe the optical, mechanical, and cryogenic design of the receiver, including the reflector design, focal-plane layout, HWP design, and free-space lowpass filters. I describe physical-optics modeling of the reflector and feedhorn to validate the optical design. A matrix model that allows the calculation of the Mueller matrix of the anti

  6. Staphylococcus aureus Leukocidin A/B (LukAB) Kills Human Monocytes via Host NLRP3 and ASC when Extracellular, but Not Intracellular

    PubMed Central

    DuMont, Ashley L.; Torres, Victor J.; Duncan, Joseph A.

    2015-01-01

    Staphylococcus aureus infections are a growing health burden worldwide, and paramount to this bacterium’s pathogenesis is the production of virulence factors, including pore-forming leukotoxins. Leukocidin A/B (LukAB) is a recently discovered toxin that kills primary human phagocytes, though the underlying mechanism of cell death is not understood. We demonstrate here that LukAB is a major contributor to the death of human monocytes. Using a variety of in vitro and ex vivo intoxication and infection models, we found that LukAB activates Caspase 1, promotes IL-1β secretion and induces necrosis in human monocytes. Using THP1 cells as a model for human monocytes, we found that the inflammasome components NLRP3 and ASC are required for LukAB-mediated IL-1β secretion and necrotic cell death. S. aureus was shown to kill human monocytes in a LukAB dependent manner under both extracellular and intracellular ex vivo infection models. Although LukAB-mediated killing of THP1 monocytes from extracellular S. aureus requires ASC, NLRP3 and the LukAB-receptor CD11b, LukAB-mediated killing from phagocytosed S. aureus is independent of ASC or NLRP3, but dependent on CD11b. Altogether, this study provides insight into the nature of LukAB-mediated killing of human monocytes. The discovery that S. aureus LukAB provokes differential host responses in a manner dependent on the cellular contact site is critical for the development of anti-infective/anti-inflammatory therapies that target the NLRP3 inflammasome. PMID:26069969

  7. Effects of Physical Exercise on Executive Functions: Going beyond Simply Moving to Moving with Thought

    PubMed Central

    Diamond, Adele

    2015-01-01

    Studies of the cognitive benefits of physical activity need to move beyond simple aerobic activities that require little thought (treadmill running, riding a stationary bicycle, or rapid walking) and resistance training. Many studies have looked at this in older adults, and the evidence points strongly to those activities having little or no cognitive benefit, certainly little or no improvement to the executive functions that depend on prefrontal cortex. There is encouraging evidence for other types of physical activity improving executive functions; however they have received far less study. PMID:26000340

  8. An analog retina model for detecting dim moving objects against a bright moving background

    NASA Technical Reports Server (NTRS)

    Searfus, R. M.; Colvin, M. E.; Eeckman, F. H.; Teeters, J. L.; Axelrod, T. S.

    1991-01-01

    We are interested in applications that require the ability to track a dim target against a bright, moving background. Since the target signal will be less than or comparable to the variations in the background signal intensity, sophisticated techniques must be employed to detect the target. We present an analog retina model that adapts to the motion of the background in order to enhance targets that have a velocity difference with respect to the background. Computer simulation results and our preliminary concept of an analog 'Z' focal plane implementation are also presented.

  9. A Tracking Sun Photometer Without Moving Parts

    NASA Technical Reports Server (NTRS)

    Strawa, Anthony W.

    2012-01-01

    This innovation is small, lightweight, and consumes very little electricity as it measures the solar energy attenuated by gases and aerosol particles in the atmosphere. A Sun photometer is commonly used on the Earth's surface, as well as on aircraft, to determine the solar energy attenuated by aerosol particles in the atmosphere and their distribution of sizes. This information is used to determine the spatial and temporal distribution of gases and aerosols in the atmosphere, as well as their distribution sizes. The design for this Sun photometer uses a combination of unique optics and a charge coupled device (CCD) array to eliminate moving parts and make the instrument more reliable. It could be selfcalibrating throughout the year. Data products would be down-welling flux, the direct-diffuse flux ratio, column abundance of gas phase constituents, aerosol optical depth at multiple-wavelengths, phase functions, cloud statistics, and an estimate of the representative size of atmospheric particles. These measurements can be used to obtain an estimate of aerosol size distribution, refractive index, and particle shape. Incident light is received at a light-reflecting (inner) surface, which is a truncated paraboloid. Light arriving from a hemispheric field of view (solid angle 2 steradians) enters the reflecting optic at an entrance aperture at, or adjacent to, the focus of the paraboloid, and is captured by the optic. Most of this light is reflected from an inner surface. The light proceeds substantially parallel to the paraboloid axis, and is detected by an array detector located near an exit aperture. Each of the entrance and exit apertures is formed by the intersection of the paraboloid with a plane substantially perpendicular to the paraboloid axis. Incident (non-reflected) light from a source of limited extent (the Sun) illuminates a limited area on the detector array. Both direct and diffuse illumination may be reflected, or not reflected, before being received on

  10. Moving-Boundary Problems Associated with Lyopreservation

    NASA Astrophysics Data System (ADS)

    Gruber, Christopher Andrew

    The work presented in this Dissertation is motivated by research into the preservation of biological specimens by way of vitrification, a technique known as lyopreservation. The operative principle behind lyopreservation is that a glassy material forms as a solution of sugar and water is desiccated. The microstructure of this glass impedes transport within the material, thereby slowing metabolism and effectively halting the aging processes in a biospecimen. This Dissertation is divided into two segments. The first concerns the nature of diffusive transport within a glassy state. Experimental studies suggest that diffusion within a glass is anomalously slow. Scaled Brownian motion (SBM) is proposed as a mathematical model which captures the qualitative features of anomalously slow diffusion while minimizing computational expense. This model is applied to several moving-boundary problems and the results are compared to a more well-established model, fractional anomalous diffusion (FAD). The virtues of SBM are based on the model's relative mathematical simplicity: the governing equation under FAD dynamics involves a fractional derivative operator, which precludes the use of analytical methods in almost all circumstances and also entails great computational expense. In some geometries, SBM allows similarity solutions, though computational methods are generally required. The use of SBM as an approximation to FAD when a system is "nearly classical'' is also explored. The second portion of this Dissertation concerns spin-drying, which is an experimental approach to biopreservation in a laboratory setting. A biospecimen is adhered to a glass wafer and this substrate is covered with sugar solution and rapidly spun on a turntable while water is evaporated from the film surface. The mathematical model for the spin-drying process includes diffusion, viscous fluid flow, and evaporation, among other contributions to the dynamics. Lubrication theory is applied to the model and an

  11. Resident responses to Section 8 relocation outcomes: "If you're gonna move, you want to move up".

    PubMed

    Walker, Laurie A

    2014-01-01

    Economic hardship and the lack of social supports of households moving with Section 8 vouchers during mixed-income redevelopment is a concern to relocation counselors. Since residents are able to select their housing location they need to know the risks and benefits of various housing choices. Twenty-five residents facing the choice of remaining in a phased redevelopment, moving with a Section 8 voucher, or moving to another public housing development were interviewed in order to determine how to engage residents in evidence-informed decision making. Many residents want to move with Section 8 vouchers, but require supports to make the choice sustainable. PMID:24405135

  12. EDITORIAL: `Il sole - no si move'

    NASA Astrophysics Data System (ADS)

    Kibble, Bob

    1999-05-01

    The Sun may not have moved for Galileo but it is certain that this coming August the Sun will have moved millions of folk towards a thin strip of land about 100 km wide stretching from Cornwall to the Indian Ocean. If you have yet to book your place for the biggest live show of this millennium year there are still places in hotels and campsites. The April edition of the UK camping and caravaning club magazine included at least four sites in Cornwall alone with vacancies. I am told that the difference between seeing a 98% eclipse and totality is considerably greater than 2%. The message appears to be - try to get to the line. However, a popular misconception among lay folk seems to be that you will only be able to see the event in Cornwall. As you will read in this issue the partial event will be visible from virtually the whole of Europe. Anyone who has tried to holiday in Cornwall or Devon will tell you how congested the roads become in any ordinary August. The best advice for this year is either to travel to the south west by bicycle or attack the totality path as it crosses Europe. Access will be much easier. For my part I have booked a hotel in Trier, Germany, about 20 km north of the totality path. An early breakfast on the 11th should leave enough time to motorcycle down to see the shadow. Of course, the whole business is weather dependent. With the chance of a clear sky in Cornwall, Devon and most of western Europe being about 50% on the date in question, forward planning depends on whether you are a `half empty' or a `half full' person. It is worth keeping this fact in mind especially if you drag an expectant family hundreds of miles through traffic just to watch the clouds drift by. Take a colouring book and a board game just in case. Of course, the chance of a clear sky increases to about 90% across Turkey but there are reasons why such a trip might not be so wise in the current political climate. In this special issue readers will find plenty to interest

  13. 40 CFR 174.506 - Bacillus thuringiensis Cry34Ab1 and Cry35Ab1 proteins in corn; exemption from the requirement of...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Bacillus thuringiensis Cry34Ab1 and Cry35Ab1 proteins in corn; exemption from the requirement of a tolerance. 174.506 Section 174.506 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PROCEDURES AND REQUIREMENTS FOR PLANT-INCORPORATED...

  14. Non Target Effect of Cry1 Ab and Cry Ab x Cry3 Bb1 Bt Transgenic Maize on Orius Insidiosus (Hemiptera: Anthocoridae) Abundance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Non-target effects of Cry1Ab x CP4 EPSPS and Cry1Ab + Cry3Bb1 x CP4 EPSPS Bt transgenic new maize hybrids on insidious flower bugs [Orius insidiosus (Say)] was studied in Nebraska (Mead, C lay Center, and Concord) during 2007 and 2008. The Bt effect was compared to CP4 EPSPS maize (isoline), convent...

  15. 24 CFR 983.260 - Family right to move.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 24 Housing and Urban Development 4 2011-04-01 2011-04-01 false Family right to move. 983.260... DEVELOPMENT PROJECT-BASED VOUCHER (PBV) PROGRAM Occupancy § 983.260 Family right to move. (a) The family may terminate the assisted lease at any time after the first year of occupancy. The family must give the...

  16. 24 CFR 983.260 - Family right to move.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 24 Housing and Urban Development 4 2014-04-01 2014-04-01 false Family right to move. 983.260... DEVELOPMENT PROJECT-BASED VOUCHER (PBV) PROGRAM Occupancy § 983.260 Family right to move. (a) The family may terminate the assisted lease at any time after the first year of occupancy. The family must give the...

  17. 24 CFR 983.260 - Family right to move.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 24 Housing and Urban Development 4 2012-04-01 2012-04-01 false Family right to move. 983.260... DEVELOPMENT PROJECT-BASED VOUCHER (PBV) PROGRAM Occupancy § 983.260 Family right to move. (a) The family may terminate the assisted lease at any time after the first year of occupancy. The family must give the...

  18. 24 CFR 983.260 - Family right to move.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 24 Housing and Urban Development 4 2013-04-01 2013-04-01 false Family right to move. 983.260... DEVELOPMENT PROJECT-BASED VOUCHER (PBV) PROGRAM Occupancy § 983.260 Family right to move. (a) The family may terminate the assisted lease at any time after the first year of occupancy. The family must give the...

  19. 24 CFR 983.260 - Family right to move.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false Family right to move. 983.260... DEVELOPMENT PROJECT-BASED VOUCHER (PBV) PROGRAM Occupancy § 983.260 Family right to move. (a) The family may terminate the assisted lease at any time after the first year of occupancy. The family must give the...

  20. Radiative transitions of excited ions moving slowly in plasmas

    SciTech Connect

    Hu, Hongwei Chen, Wencong; Li, Peng; Zhao, Yongtao; Zhou, Xianming; Li, Zhen; Li, Fuli; Dong, Chenzhong

    2014-12-15

    The electric dipole transitions of excited ions moving slowly in plasmas are studied. The results show that some transitions forbidden for excited ions at rest become allowed for moving excited ions. The transition rates change with varying speed of the ions. Forbidden transitions are strongly influenced by the speed, non-forbidden transitions are weakly influenced.