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Sample records for multiple triaxial sd

  1. Multiple triaxial bands in 138Nd

    NASA Astrophysics Data System (ADS)

    Petrache, C. M.; Ragnarsson, I.; Ma, Hai-Liang; Leguillon, R.; Zerrouki, T.; Bazzacco, D.; Lunardi, S.

    2015-02-01

    High-spin states in 138Nd were investigated by using the 48Ca+94Zr reaction and γ -ray coincidences were acquired with the GASP spectrometer. A rich level scheme was developed including 14 new bands of quadrupole transitions at very high spins. Linking transitions connecting 11 high-spin bands to low-energy states have been observed. Calculations based on the cranked Nilsson-Strutinsky formalism have been used to assign configurations to the observed bands. The main result of these calculations is that all 14 bands exhibit a stable triaxial deformation up to the highest observed spins, giving strong support to the existence of a triaxial minimum with normal deformation and positive asymmetry parameter in nuclei with a few holes in the N =82 shell closure.

  2. Triaxial superdeformation in {sup 40}Ar

    SciTech Connect

    Taniguchi, Yasutaka; Ikeda, Kiyomi; Kanada-En'yo, Yoshiko; Kimura, Masaaki; Horiuchi, Hisashi; Ideguchi, Eiji

    2010-07-15

    Superdeformed (SD) states in {sup 40}Ar have been studied using the deformed-basis antisymmetrized molecular dynamics. Low-energy states were calculated by the parity and angular momentum projection and the generator coordinate method (GCM). Basis wave functions were obtained by the energy variation with a constraint on the quadrupole deformation parameter beta, while other quantities such as triaxiality gamma were optimized by the energy variation. By the GCM calculation, an SD band was obtained just above the ground-state band. The SD band involves a K{sup p}i=2{sup +} side band due to the triaxiality. The calculated electric quadrupole transition strengths of the SD band reproduce the experimental values appropriately. Triaxiality is significant for understanding low-lying states.

  3. Chiral Bands and Triaxiality

    SciTech Connect

    Petrache, C.M.

    2004-02-27

    The results obtained with the GASP array in the A=130 mass region are reviewed, emphasizing the discovery excited highly-deformed bands and their decay out, the study of the odd-odd Pr nuclei up to high spins, the discovery of stable triaxial bands in Nd nuclei close to the N=82 shell closure. The very recent studies of nuclei near the proton drip line are described. A discussion of the origin of the various doublet bands observed in odd-odd nuclei of the A=130 mass region is presented.

  4. Triaxial Probe Magnetic Data Analysis

    NASA Technical Reports Server (NTRS)

    Shultz, Kimberly; Whittlesey, Albert; Narvaez, Pablo

    2007-01-01

    The Triaxial Magnetic Moment Analysis software uses measured magnetic field test data to compute dipole and quadrupole moment information from a hardware element. It is used to support JPL projects needing magnetic control and an understanding of the spacecraft-generated magnetic fields. Evaluation of the magnetic moment of an object consists of three steps: acquisition, conditioning, and analysis. This version of existing software was extensively rewritten for easier data acquisition, data analysis, and report presentation, including immediate feedback to the test operator during data acquisition. While prior JPL computer codes provided the same data content, this program has a better graphic display including original data overlaid with reconstructed results to show goodness of fit accuracy and better appearance of the report graphic page. Data are acquired using three magnetometers and two rotations of the device under test. A clean acquisition user interface presents required numeric data and graphic summaries, and the analysis module yields the best fit (least squares) for the magnetic dipole and/or quadrupole moment of a device. The acquisition module allows the user to record multiple data sets, selecting the best data to analyze, and is repeated three times for each of the z-axial and y-axial rotations. In this update, the y-axial rotation starting position has been changed to an option, allowing either the x- or z-axis to point towards the magnetometer. The code has been rewritten to use three simultaneous axes of magnetic data (three probes), now using two "rotations" of the device under test rather than the previous three rotations, thus reducing handling activities on the device under test. The present version of the software gathers data in one-degree increments, which permits much better accuracy of the fit ted data than the coarser data acquisition of the prior software. The data-conditioning module provides a clean data set for the analysis module

  5. The Triaxial Klystron

    NASA Astrophysics Data System (ADS)

    Pasour, John; Smithe, David; Friedman, Moshe

    1999-05-01

    We describe a high-power, annular beam klystron, the Triaxial Klystron, that promises high efficiency at GW power levels and frequencies up to X band. Higher frequency operation should be possible at reduced power levels. The device consists of a thin annular electron beam propagating in an annular drift region, with cavity structures located inside and outside the beam. So long as the width of the drift region is less than half a wavelength (to cut off TM modes), the beam diameter can be as large as necessary to accommodate the required current and to reduce the RF surface fields to tolerable levels. Beam transport and stability are also facilitated in the annular channel. Simulations at X-band (using MRC's particle-in-cell code, MAGIC) show strong beam bunching and efficient energy extraction from specially designed radial cavity structures. Initial experiments at the Naval Research Laboratory have demonstrated transport of a 16-kA, 400-keV beam over a distance of ˜1 m with no evidence of instability or asymmetry. Strong bunching of such a beam has been produced at X band using a coaxially-driven input cavity and a multi-gap buncher cavity structure. The peak-to-peak modulated current amplitude from this simple structure exceeds the injected current amplitude and is stable throughout the 150 nsec pulse.

  6. Transgenerational Effects of Di (2-Ethylhexyl) Phthalate in the Male CRL:CD(SD) Rat: Added Value of Assessing Multiple Offspring per Litter

    PubMed Central

    Gray, Leon Earl; Barlow, Norman J.; Howdeshell, Kembra L.; Ostby, Joseph S.; Furr, Johnathan R.; Gray, Clark L.

    2009-01-01

    In the rat, some phthalates alter sexual differentiation at relatively low dosage levels by altering fetal Leydig cell development and hormone synthesis, thereby inducing abnormalities of the testis, gubernacular ligaments, epididymis, and other androgen-dependent tissues. In order to define the dose-response relationship between di(2-ethylhexyl) phthalate (DEHP) and the Phthalate Syndrome of reproductive alterations in F1 male rats, Sprague-Dawley (SD) rat dams were dosed by gavage from gestational day 8 to day 17 of lactation with 0, 11, 33, 100, or 300 mg/kg/day DEHP (71–93 males per dose from 12 to 14 litters per dose). Some of the male offspring continued to be exposed to DEHP via gavage from 18 days of age to necropsy at 63–65 days of age (PUB cohort; 16–20/dose). Remaining males were not exposed after postnatal day 17 (in utero-lactational [IUL] cohort) and were necropsied after reaching full maturity. Anogenital distance, sperm counts and reproductive organ weights were reduced in F1 males in the 300 mg/kg/day group and they displayed retained nipples. In the IUL cohort, seminal vesicle weight also was reduced at 100 mg/kg/day. In contrast, serum testosterone and estradiol levels were unaffected in either the PUB or IUL cohorts at necropsy. A significant percentage of F1 males displayed one or more Phthalate Syndrome lesions at 11 mg/kg/day DEHP and above. We were able to detect effects in the lower dose groups only because we examined all the males in each litter rather than only one male per litter. Power calculations demonstrate how using multiple males versus one male/litter enhances the detection of the effects of DEHP. The results at 11 mg/kg/day confirm those reported from a National Toxicology Program multigenerational study which reported no observed adverse effect levels-lowest observed adverse effect levels of 5 and 10 mg/kg/day DEHP, respectively, via the diet. PMID:19482887

  7. X-Band Triaxial Klystron

    NASA Astrophysics Data System (ADS)

    Pasour, John; Smithe, David; Ludeking, Larry

    2003-12-01

    A prototype, low-repetition-rate triaxial klystron amplifier (TKA) has been fabricated and tested. This device is powered by an annular electron beam (˜400 kV, 3.5 kA). The TKA operates at 9.3 GHz at power levels >100 MW and with a pulse duration of 750 nsec.

  8. Calibration of triaxial fluxgate gradiometer

    SciTech Connect

    Vcelak, Jan

    2006-04-15

    The description of simple and fast calibration procedures used for double-probe triaxial fluxgate gradiometer is provided in this paper. The calibration procedure consists of three basic steps. In the first step both probes are calibrated independently in order to reach constant total field reading in every position. Both probes are numerically aligned in the second step in order that the gradient reading is zero in homogenous magnetic field. The third step consists of periodic drift calibration during measurement. The results and detailed description of each calibration step are presented and discussed in the paper. The gradiometer is finally verified during the detection of the metal object in the measuring grid.

  9. Dynamics of gas disks in triaxial galaxies

    SciTech Connect

    Steiman-Cameron, T.Y.

    1984-01-01

    Increasing evidence has accumulated since the mid 1970's arguing that many, if not all, undisturbed galaxies may have triaxial mass distributions. The steady state configurations (preferred planes) of gas disks in triaxial galaxies with static and rotating surface figures is determined. In addition, the evolution of a gas disk as it settles into the steady state is followed for both axisymmetric and triaxial galaxies. Observational tests are provided for triaxial galactic geometry and give more accurate measures of settling times than those previously published. The preferred planes for gas disks in static and tumbling triaxial galaxies are determined using an analytic method derived from celestial mechanics. The evolution of gas disks which are not in the steady state is followed using numerical methods.

  10. NDPC-SD Data Probes Worksheet

    ERIC Educational Resources Information Center

    National Dropout Prevention Center for Students with Disabilities, 2011

    2011-01-01

    This worksheet from the National Dropout Prevention Center for Students with Disabilities (NDPC-SD) is an optional tool to help schools organize multiple years of student and program data for the purpose of identifying school-completion needs that can be addressed through the implementation of research-based interventions. It is designed for use…

  11. The LMF triaxial MITL voltage adder system

    SciTech Connect

    Mazarakis, M.G.; Smith, D.L.; Bennett, L.F.; Lockner, T.R.; Olson, R.E.; Poukey, J.W.

    1992-12-31

    The light-ion microfusion driver design consists of multiple accelerating modules fired in coincidence and sequentially in order to provide the desired ion energy, power pulse shape and energy deposition uniformity on an Inertial Confinement Fusion (ICF) target. The basic energy source is a number of Marx generators which, through the appropriate pulse power conditioning, provide the necessary voltage pulse wave form to the accelerating gaps or feeds of each module. The cavity gaps are inductively isolated, and the voltage addition occurs in the center conductor of the voltage adder which is the positive electrode while the electrons of the sheath flow closer to the outer cylinder which is the magnetically insulated cathode electrode. Each module powers a separate two-stage extraction diode which provides a low divergence ion beam. In order to provide the two separate voltage pulses required by the diode, a triaxial adder system is designed for each module. The voltage addition occurs in two separate MITLs. The center hollow cylinder (anode) of the second MITL also serves as the outer cathode electrode for the extension of the first voltage adder MITL. The voltage of the second stage is about twice that of the first stage. The cavities are connected in series to form the outer cylinder of each module. The accelerating modules are positioned radially in a symmetrical way around the fusion chamber. A preliminary conceptual design of the LMF modules with emphasis on the voltage adders and extension MITLs will be presented and discussed.

  12. Superdeformed and Triaxial States in 42Ca

    NASA Astrophysics Data System (ADS)

    Hadyńska-KlÈ©k, K.; Napiorkowski, P. J.; Zielińska, M.; Srebrny, J.; Maj, A.; Azaiez, F.; Valiente Dobón, J. J.; Kicińska-Habior, M.; Nowacki, F.; Naïdja, H.; Bounthong, B.; Rodríguez, T. R.; de Angelis, G.; Abraham, T.; Anil Kumar, G.; Bazzacco, D.; Bellato, M.; Bortolato, D.; Bednarczyk, P.; Benzoni, G.; Berti, L.; Birkenbach, B.; Bruyneel, B.; Brambilla, S.; Camera, F.; Chavas, J.; Cederwall, B.; Charles, L.; Ciemała, M.; Cocconi, P.; Coleman-Smith, P.; Colombo, A.; Corsi, A.; Crespi, F. C. L.; Cullen, D. M.; Czermak, A.; Désesquelles, P.; Doherty, D. T.; Dulny, B.; Eberth, J.; Farnea, E.; Fornal, B.; Franchoo, S.; Gadea, A.; Giaz, A.; Gottardo, A.; Grave, X.; GrÈ©bosz, J.; Görgen, A.; Gulmini, M.; Habermann, T.; Hess, H.; Isocrate, R.; Iwanicki, J.; Jaworski, G.; Judson, D. S.; Jungclaus, A.; Karkour, N.; Kmiecik, M.; Karpiński, D.; Kisieliński, M.; Kondratyev, N.; Korichi, A.; Komorowska, M.; Kowalczyk, M.; Korten, W.; Krzysiek, M.; Lehaut, G.; Leoni, S.; Ljungvall, J.; Lopez-Martens, A.; Lunardi, S.; Maron, G.; Mazurek, K.; Menegazzo, R.; Mengoni, D.; Merchán, E.; MÈ©czyński, W.; Michelagnoli, C.; Mierzejewski, J.; Million, B.; Myalski, S.; Napoli, D. R.; Nicolini, R.; Niikura, M.; Obertelli, A.; Özmen, S. F.; Palacz, M.; Próchniak, L.; Pullia, A.; Quintana, B.; Rampazzo, G.; Recchia, F.; Redon, N.; Reiter, P.; Rosso, D.; Rusek, K.; Sahin, E.; Salsac, M.-D.; Söderström, P.-A.; Stefan, I.; Stézowski, O.; Styczeń, J.; Theisen, Ch.; Toniolo, N.; Ur, C. A.; Vandone, V.; Wadsworth, R.; Wasilewska, B.; Wiens, A.; Wood, J. L.; Wrzosek-Lipska, K.; ZiÈ©bliński, M.

    2016-08-01

    Shape parameters of a weakly deformed ground-state band and highly deformed slightly triaxial sideband in 42Ca were determined from E 2 matrix elements measured in the first low-energy Coulomb excitation experiment performed with AGATA. The picture of two coexisting structures is well reproduced by new state-of-the-art large-scale shell model and beyond-mean-field calculations. Experimental evidence for superdeformation of the band built on 02+ has been obtained and the role of triaxiality in the A ˜40 mass region is discussed. Furthermore, the potential of Coulomb excitation as a tool to study superdeformation has been demonstrated for the first time.

  13. Superdeformed and Triaxial States in ^{42}Ca.

    PubMed

    Hadyńska-Klȩk, K; Napiorkowski, P J; Zielińska, M; Srebrny, J; Maj, A; Azaiez, F; Valiente Dobón, J J; Kicińska-Habior, M; Nowacki, F; Naïdja, H; Bounthong, B; Rodríguez, T R; de Angelis, G; Abraham, T; Anil Kumar, G; Bazzacco, D; Bellato, M; Bortolato, D; Bednarczyk, P; Benzoni, G; Berti, L; Birkenbach, B; Bruyneel, B; Brambilla, S; Camera, F; Chavas, J; Cederwall, B; Charles, L; Ciemała, M; Cocconi, P; Coleman-Smith, P; Colombo, A; Corsi, A; Crespi, F C L; Cullen, D M; Czermak, A; Désesquelles, P; Doherty, D T; Dulny, B; Eberth, J; Farnea, E; Fornal, B; Franchoo, S; Gadea, A; Giaz, A; Gottardo, A; Grave, X; Grȩbosz, J; Görgen, A; Gulmini, M; Habermann, T; Hess, H; Isocrate, R; Iwanicki, J; Jaworski, G; Judson, D S; Jungclaus, A; Karkour, N; Kmiecik, M; Karpiński, D; Kisieliński, M; Kondratyev, N; Korichi, A; Komorowska, M; Kowalczyk, M; Korten, W; Krzysiek, M; Lehaut, G; Leoni, S; Ljungvall, J; Lopez-Martens, A; Lunardi, S; Maron, G; Mazurek, K; Menegazzo, R; Mengoni, D; Merchán, E; Mȩczyński, W; Michelagnoli, C; Mierzejewski, J; Million, B; Myalski, S; Napoli, D R; Nicolini, R; Niikura, M; Obertelli, A; Özmen, S F; Palacz, M; Próchniak, L; Pullia, A; Quintana, B; Rampazzo, G; Recchia, F; Redon, N; Reiter, P; Rosso, D; Rusek, K; Sahin, E; Salsac, M-D; Söderström, P-A; Stefan, I; Stézowski, O; Styczeń, J; Theisen, Ch; Toniolo, N; Ur, C A; Vandone, V; Wadsworth, R; Wasilewska, B; Wiens, A; Wood, J L; Wrzosek-Lipska, K; Ziȩbliński, M

    2016-08-01

    Shape parameters of a weakly deformed ground-state band and highly deformed slightly triaxial sideband in ^{42}Ca were determined from E2 matrix elements measured in the first low-energy Coulomb excitation experiment performed with AGATA. The picture of two coexisting structures is well reproduced by new state-of-the-art large-scale shell model and beyond-mean-field calculations. Experimental evidence for superdeformation of the band built on 0_{2}^{+} has been obtained and the role of triaxiality in the A∼40 mass region is discussed. Furthermore, the potential of Coulomb excitation as a tool to study superdeformation has been demonstrated for the first time.

  14. Rotational Kinematics and Torques for Triaxial Bodies: A Simple Derivation of Precession with Synchronous Locking

    NASA Astrophysics Data System (ADS)

    Newman, William I.

    2012-05-01

    Precession of the equinoxes and of satellite orbits for axisymmetric bodies is a celebrated part of the classical and orbital mechanics literature. The theory underlying the behavior of triaxial bodies, particularly when synchronous phase locking is present, has proven to be difficult to evaluate and controversial. We perform a first-principles derivation where we incorporate triaxial geometry into the analysis using a straightforward description of the configuration. We calculate the effect of triaxiality and phase locking upon precession rates by using multiple time scales techniques. This is required to make possible the direct numerical integration of the kinematic equations of motion over solar system time scales. In so doing, we provide a simple derivation of the time-averaged gravitational potential and the associated torque that drives precession, and resolve an outstanding controversy emerging from its calculation.

  15. Miniature piezoelectric triaxial accelerometer measures cranial accelerations

    NASA Technical Reports Server (NTRS)

    Deboo, G. J.; Rogallo, V. L.

    1966-01-01

    Tiny triaxial accelerometer whose sensing elements are piezoelectric ceramic beams measures human cranial accelerations when a subject is exposed to a centrifuge or other simulators of g environments. This device could be considered for application in dental, medical, and automotive safety research.

  16. SD46 Facilities and Capabilities

    NASA Technical Reports Server (NTRS)

    Ramachandran, N.; Curreri, Peter A. (Technical Monitor)

    2002-01-01

    The displays for the Materials Conference presents some of the facilities and capabilities in SD46 that can be useful to a prospective researcher from University, Academia or other government labs. Several of these already have associated personnel as principal and co-investigators on NASA peer reviewed science investigations. 1. SCN purification facility 2. ESL facility 3. Static and Dynamic magnetic field facility 4. Microanalysis facility 5. MSG Investigation - PFMI 6. Thermo physical Properties Measurement Capabilities.

  17. Superdeformed and Triaxial States in ^{42}Ca.

    PubMed

    Hadyńska-Klȩk, K; Napiorkowski, P J; Zielińska, M; Srebrny, J; Maj, A; Azaiez, F; Valiente Dobón, J J; Kicińska-Habior, M; Nowacki, F; Naïdja, H; Bounthong, B; Rodríguez, T R; de Angelis, G; Abraham, T; Anil Kumar, G; Bazzacco, D; Bellato, M; Bortolato, D; Bednarczyk, P; Benzoni, G; Berti, L; Birkenbach, B; Bruyneel, B; Brambilla, S; Camera, F; Chavas, J; Cederwall, B; Charles, L; Ciemała, M; Cocconi, P; Coleman-Smith, P; Colombo, A; Corsi, A; Crespi, F C L; Cullen, D M; Czermak, A; Désesquelles, P; Doherty, D T; Dulny, B; Eberth, J; Farnea, E; Fornal, B; Franchoo, S; Gadea, A; Giaz, A; Gottardo, A; Grave, X; Grȩbosz, J; Görgen, A; Gulmini, M; Habermann, T; Hess, H; Isocrate, R; Iwanicki, J; Jaworski, G; Judson, D S; Jungclaus, A; Karkour, N; Kmiecik, M; Karpiński, D; Kisieliński, M; Kondratyev, N; Korichi, A; Komorowska, M; Kowalczyk, M; Korten, W; Krzysiek, M; Lehaut, G; Leoni, S; Ljungvall, J; Lopez-Martens, A; Lunardi, S; Maron, G; Mazurek, K; Menegazzo, R; Mengoni, D; Merchán, E; Mȩczyński, W; Michelagnoli, C; Mierzejewski, J; Million, B; Myalski, S; Napoli, D R; Nicolini, R; Niikura, M; Obertelli, A; Özmen, S F; Palacz, M; Próchniak, L; Pullia, A; Quintana, B; Rampazzo, G; Recchia, F; Redon, N; Reiter, P; Rosso, D; Rusek, K; Sahin, E; Salsac, M-D; Söderström, P-A; Stefan, I; Stézowski, O; Styczeń, J; Theisen, Ch; Toniolo, N; Ur, C A; Vandone, V; Wadsworth, R; Wasilewska, B; Wiens, A; Wood, J L; Wrzosek-Lipska, K; Ziȩbliński, M

    2016-08-01

    Shape parameters of a weakly deformed ground-state band and highly deformed slightly triaxial sideband in ^{42}Ca were determined from E2 matrix elements measured in the first low-energy Coulomb excitation experiment performed with AGATA. The picture of two coexisting structures is well reproduced by new state-of-the-art large-scale shell model and beyond-mean-field calculations. Experimental evidence for superdeformation of the band built on 0_{2}^{+} has been obtained and the role of triaxiality in the A∼40 mass region is discussed. Furthermore, the potential of Coulomb excitation as a tool to study superdeformation has been demonstrated for the first time. PMID:27541463

  18. Inertial modes in a rotating triaxial ellipsoid

    PubMed Central

    Vantieghem, S.

    2014-01-01

    In this work, we present an algorithm that enables computation of inertial modes and their corresponding frequencies in a rotating triaxial ellipsoid. The method consists of projecting the inertial mode equation onto finite-dimensional bases of polynomial vector fields. It is shown that this leads to a well-posed eigenvalue problem, and hence, that eigenmodes are of polynomial form. Furthermore, these results shed new light onto the question whether the eigenmodes form a complete basis, i.e. whether any arbitrary velocity field can be expanded in a sum of inertial modes. Finally, we prove that two intriguing integral properties of inertial modes in rotating spheres and spheroids also extend to triaxial ellipsoids. PMID:25104908

  19. Burst Testing of Triaxial Braided Composite Tubes

    NASA Technical Reports Server (NTRS)

    Salem, J. A.; Bail, J. L.; Wilmoth, N. G.; Ghosn, L. J.; Kohlman, L. W.; Roberts, G. D.; Martin, R. E.

    2014-01-01

    Applications using triaxial braided composites are limited by the materials transverse strength which is determined by the delamination capacity of unconstrained, free-edge tows. However, structural applications such as cylindrical tubes can be designed to minimize free edge effects and thus the strength with and without edge stresses is relevant to the design process. The transverse strength of triaxial braided composites without edge effects was determined by internally pressurizing tubes. In the absence of edge effects, the axial and transverse strength were comparable. In addition, notched specimens, which minimize the effect of unconstrained tow ends, were tested in a variety of geometries. Although the commonly tested notch geometries exhibited similar axial and transverse net section failure strength, significant dependence on notch configuration was observed. In the absence of unconstrained tows, failure ensues as a result of bias tow rotation, splitting, and fracture at cross-over regions.

  20. On the pairing effects in triaxial nuclei

    SciTech Connect

    Oudih, M. R.; Fellah, M.; Allal, N. H.

    2014-03-05

    Triaxial deformation effect on the pairing correlations is studied in the framework of the Skyrme Hartree-Fock-Bogoliubov theory. Quantities such as binding energy, gap parameter and particle-number fluctuation are considered in neutron-rich Mo isotopes. The results are compared with those of axially symmetric calculation and with available experimental data. The role played by the particle-number projection is outlined.

  1. Triaxial and Triaxial Softness in Neutron Rich ru and pd Nuclei

    NASA Astrophysics Data System (ADS)

    Luo, Y. X.; Hamilton, J. H.; Ramaya, A. V.; Hwang, J. K.; Liu, S. H.; Rasmussen, J. O.; Frauendorf, S.; Ter-Akopian, G. M.; Daniel, A. V.; Oganessian, Yu. Ts.; Zhu, S. J.

    2013-06-01

    The level structures of 108,110,112Ru (Z=44) and 112,114,115,116,117,118Pd (Z=46) have been significantly expanded through studies of prompt γ-γ-γ coincidences observed with Gammasphere following the spontaneous fission of 252Cf. The softness to triaxiality perturbs the band structures of 108Ru and even-N Pd isotopes. Two sets of odd-parity bands are identified in 112,114,116Pd similar to but different from those in 110,112Ru. These differences can be accounted for by interferences of the chiral doubling and softness to triaxiality. Also in 112Ru, evidence for wobbling motion is found in the behavior of the γ vibrational band. Similar evidence for wobbling motion is found in 114Pd, the N = 68 isotone of 112Ru.

  2. Low Noise Borehole Triaxial Seismometer Phase II

    SciTech Connect

    Kerr, James D; McClung, David W

    2006-11-06

    This report describes the preliminary design and the effort to date of Phase II of a Low Noise Borehole Triaxial Seismometer for use in networks of seismic stations for monitoring underground nuclear explosions. The design uses the latest technology of broadband seismic instrumentation. Each parameter of the seismometer is defined in terms of the known physical limits of the parameter. These limits are defined by the commercially available components, and the physical size constraints. A theoretical design is proposed, and a preliminary prototype model of the proposed instrument has been built. This prototype used the sensor module of the KS2000. The installation equipment (hole locks, etc.) has been designed and one unit has been installed in a borehole. The final design of the sensors and electronics and leveling mechanism is in process. Noise testing is scheduled for the last quarter of 2006.

  3. True triaxial testing of Castlegate sandstone.

    SciTech Connect

    Ingraham, M. D.; Holcomb, David Joseph; Issen, Kathleen A.

    2010-03-01

    Deformation bands in high porosity sandstone are an important geological feature for geologists and petroleum engineers; however, their formation is not fully understood. Axisymmetric compression, the common test for this material, is not sufficient to fully evaluate localization criteria. This study seeks to investigate the influence of the second principal stress on the failure and the formation of deformation bands in Castlegate sandstone. Experimental results from tests run in the axisymmetric compression stress state, as well as a stress state between axisymmetric compression and pure shear will be presented. Samples are tested using a custom triaxial testing rig at Sandia National Laboratories capable of applying stresses up to 400 MPa. Acoustic emissions are used to locate deformation bands should they not be visible on the specimen exterior. It is suspected that the second invariant of stress has a strong contribution to the failure mode and band formation. These results could have significant bearing on petroleum extraction as well as carbon dioxide sequestration.

  4. Triaxial bands in {sup {bold 133}}Ce

    SciTech Connect

    Hauschild, K.; Wadsworth, R.; Clark, R.M.; Hibbert, I.M.; Fallon, P.; Macchiavelli, A.O.; Fossan, D.B.; Schnare, H.; Thorslund, I.; Nolan, P.J.; Semple, A.T.; Walker, L.

    1996-08-01

    An experiment performed on the early implementation of the GAMMASPHERE array to populate the high-spin states in {sup 133}Ce has revealed the presence of several rotational structures with energy spacings of {Delta}{ital E}{sub {gamma}}{approximately}100 keV. Some of these bands exhibit a backbend at {h_bar}{omega}{approximately}0.6 MeV and are observed to high rotational frequencies{emdash}{h_bar}{omega}{approximately}0.85 MeV. These characteristics are very different from those observed for any other rotational bands in this mass region. The properties of these new structures will be discussed within the framework of cranked Strutinsky-Woods-Saxon calculations. Currently, these bands are thought to be based on triaxial nuclear shapes. {copyright} {ital 1996 The American Physical Society.}

  5. Borehole Effects in Triaxial Induction Logging

    SciTech Connect

    Bertete-Aguirre, H; Cherkaev, E; Tripp, A

    2000-09-15

    Traditional induction tools use source arrays in which both receiving and transmitting magnetic dipoles are oriented along the borehole axis. This orientation has been preferred for traditional isotropic formation evaluation in vertical boreholes because borehole effects are minimized by the source-receiver-borehole symmetry. However, this source-receiver geometry tends to minimize the response of potentially interesting geological features? such as bed resistivity anisotropy and fracturing which parallels the borehole. Traditional uniaxial tool responses are also ambiguous in highly deviated boreholes in horizontally layered formations. Resolution of these features would be enhanced by incorporating one or more source transmitters that are perpendicular to the borehole axis. Although these transmitters can introduce borehole effects, resistive oil-based muds minimize borehole effects for horizontal source data collection and interpretation. However, the use of oil based muds is contraindicated in environmentally sensitive areas. For this reason, it is important to be able to assess the influence of conductive water based muds on the new generation of triaxial induction tools directed toward geothermal resource evaluation and to develop means of ameliorating any deleterious effects. The present paper investigates the effects of a borehole on triaxial measurements. The literature contains a great deal of work on analytic expressions for the EM response of a magnetic dipole contained in a borehole with possible invasion zones. Moran and Gianzero (1979) for example investigate borehole effects using such an expression. They show that for conductive borehole fluids, the borehole response can easily swamp the formation response for horizontal dipoles. This is also true when the source dipoles are enclosed in a resistive cavity, as shown by Howard (1981) using a mode match modeling technique.

  6. ORBITS AROUND BLACK HOLES IN TRIAXIAL NUCLEI

    SciTech Connect

    Merritt, David; Vasiliev, Eugene E-mail: eugvas@lpi.ru

    2011-01-10

    We discuss the properties of orbits within the influence sphere of a supermassive black hole (BH), in the case that the surrounding star cluster is non-axisymmetric. There are four major orbit families; one of these, the pyramid orbits, have the interesting property that they can approach arbitrarily closely to the BH. We derive the orbit-averaged equations of motion and show that in the limit of weak triaxiality, the pyramid orbits are integrable: the motion consists of a two-dimensional libration of the major axis of the orbit about the short axis of the triaxial figure, with eccentricity varying as a function of the two orientation angles and reaching unity at the corners. Because pyramid orbits occupy the lowest angular momentum regions of phase space, they compete with collisional loss cone repopulation and with resonant relaxation (RR) in supplying matter to BHs. General relativistic advance of the periapse dominates the precession for sufficiently eccentric orbits, and we show that relativity imposes an upper limit to the eccentricity: roughly the value at which the relativistic precession time is equal to the time for torques to change the angular momentum. We argue that this upper limit to the eccentricity should also apply to evolution driven by RR, with potentially important consequences for the rate of extreme-mass-ratio inspirals in low-luminosity galaxies. In giant galaxies, we show that capture of stars on pyramid orbits can dominate the feeding of BHs, at least until such a time as the pyramid orbits are depleted; however this time can be of order a Hubble time.

  7. Comparison of physical activity energy expenditure in Japanese adolescents assessed by EW4800P triaxial accelerometry and the doubly labelled water method.

    PubMed

    Ishikawa-Takata, Kazuko; Kaneko, Kayoko; Koizumi, Kayo; Ito, Chinatsu

    2013-10-01

    The present study compared the accuracy of triaxial accelerometry and the doubly labelled water (DLW) method for measuring physical activity (PA) in Japanese adolescents. A total of sixty adolescents aged 12-15 years were analysed. The total energy expenditure (TEE) was measured over 7 d by the DLW method and with an EW4800P triaxial accelerometer (Panasonic Corporation). The measured (RMR)(m) and predicted RMR (RMR(p)) were 5·7 (SD 0·9) and 6·0 (SD 1·0) MJ/d, respectively. TEE measured by the DLW method and accelerometry using RMR(m) or RMR(p) were 11·0 (SD 2·6), 10·3 (SD 1·9), and 10·7 (SD 2·1) MJ/d, respectively. The PA levels (PAL) measured by the DLW method using RMR(m) or RMR(p) were 1·97 (SD 0·31) and 1·94 (SD 0·31) in subjects who exercised, and 1·85 (SD 0·27) and 1·74 (SD 0·29) in subjects who did not exercise. The percentage of body fat correlated significantly with the percentage difference between RMR(m) v. RMR(p), TEE, PA energy expenditure (PAEE) and PAL using RMR(p), and PAL using RMR(m) assessed by the DLW method and accelerometry. The present data showed that while accelerometry estimated TEE accurately, it did not provide the precise measurement of PAEE and PAL. The error in accelerometry was attributed to the prediction error of RMR and assessment in exercise. PMID:23544366

  8. The Evolution of Cuspy Triaxial Galaxies Harboring Central Black Holes

    NASA Astrophysics Data System (ADS)

    Holley-Bockelmann, Kelly; Mihos, J. Christopher; Sigurdsson, Steinn; Hernquist, Lars; Norman, Colin

    2002-03-01

    We use numerical simulations to study the evolution of triaxial elliptical galaxies with central black holes. In contrast to earlier studies which used galaxy models with central density ``cores,'' our galaxies have steep central cusps, as observed in real ellipticals. As a black hole grows in these cuspy triaxial galaxies, the inner regions become rounder owing to chaos induced in the orbital families that populate the model. At larger radii, however, the models maintain their triaxiality, and orbital analyses show that centrophilic orbits there resist stochasticity over many dynamical times. While black hole-induced evolution is strong in the inner regions of these galaxies and reaches out beyond the nominal ``sphere of influence'' of a black hole, our simulations do not show evidence for a rapid global transformation of the host. The triaxiality of observed elliptical galaxies is therefore not inconsistent with the presence of supermassive black holes at their centers.

  9. Respiratory gas exchange using a triaxial alveolar gas diagram.

    PubMed Central

    Fuster, J. F.; Pages, T.; Palacios, L.

    1993-01-01

    A triaxial alveolar gas diagram to depict fractional concentration of oxygen, carbon dioxide and nitrogen is described, in which the R = 1 line is always implicit. Although it is not claimed that this representation leads to new insights into respiratory physiology, a method of plotting on a triaxial coordinate system has been found to be well suited to many applications when a direct display of fractional nitrogen concentration is required. PMID:8303637

  10. A nonlinear criterion for triaxial strength of inherently anisotropic rocks

    NASA Astrophysics Data System (ADS)

    Singh, Mahendra; Samadhiya, N. K.; Kumar, Ajit; Kumar, Vivek; Singh, Bhawani

    2015-07-01

    Rocks encountered at many underground construction sites are laminated and exhibit direction-dependent strength behavior. It is also a well-established fact that the strength varies in a nonlinear manner with confining pressure. There is a need of strength criterion which could capture the nonlinearity as well as the anisotropy in the triaxial strength behavior of the rocks. It is essential that the criterion should be simple and must involve minimum testing to the extent possible. Further, the parameters of the criterion should have wide acceptability among the geotechnical fraternity. In the present study, a nonlinear strength criterion for transversely isotropic rocks is presented. Critical state concept Barton (Int J Rock Mech Mining Sci Geomech Abstr 13(9):255-279, 1976) has been used to define the curvature of the criterion. With a correctly defined curvature and starting from a reference point (UCS), it is possible to accurately assess the triaxial strength for given confining pressure. An experimental study conducted on triaxial strength behavior of three types of anisotropic rocks namely phyllite, slate and orthoquartzite has been discussed. A data base comprising more than 1140 triaxial tests conducted worldwide on anisotropic rocks has been compiled. Statistical evaluation of goodness of fit of the proposed criterion to the data base has been carried out. Further, the predictive capabilities of the proposed criterion have been evaluated by determining the error in estimation of triaxial strength if only few triaxial test data are available for determining the criterion parameters. The data base has also been back analyzed to assess the critical confining pressure for anisotropic rocks. Statistically, the critical confining pressure for anisotropic rocks can be taken nearly equal to 1.25 times the maximum UCS (obtained by applying load either parallel or perpendicular to planes of anisotropy). It is concluded that reasonable estimates of the triaxial

  11. Ambulatory respiratory rate detection using ECG and a triaxial accelerometer.

    PubMed

    Chan, Alexander M; Ferdosi, Nima; Narasimhan, Ravi

    2013-01-01

    Continuous monitoring of respiratory rate in ambulatory conditions has widespread applications for screening of respiratory diseases and remote patient monitoring. Unfortunately, minimally obtrusive techniques often suffer from low accuracy. In this paper, we describe an algorithm with low computational complexity for combining multiple respiratory measurements to estimate breathing rate from an unobtrusive chest patch sensor. Respiratory rates derived from the respiratory sinus arrhythmia (RSA) and modulation of the QRS amplitude of electrocardiography (ECG) are combined with a respiratory rate derived from tri-axial accelerometer data. The three respiration rates are combined by a weighted average using weights based on quality metrics for each signal. The algorithm was evaluated on 15 elderly subjects who performed spontaneous and metronome breathing as well as a variety of activities of daily living (ADLs). When compared to a reference device, the mean absolute error was 1.02 breaths per minute (BrPM) during metronome breathing, 1.67 BrPM during spontaneous breathing, and 2.03 BrPM during ADLs.

  12. Triaxial Burke-Schumann Flames with Applications to Flame Synthesis

    NASA Technical Reports Server (NTRS)

    Chao, B. H.; Axelbaum, R. L.; Gokoglu, Suleyman (Technical Monitor)

    2000-01-01

    The problem of a flame generated by three coaxial flows is solved by extending the Burke-Schumann methodology to include a third stream. The solution is particularly relevant to flame synthesis wherein multiple tubes are often employed either to introduce inert as a diffusion barrier or to introduce more than two reactants. The general problem is solved where the inner and outer tubes contain reactants and the middle tube contains either an inert or a third reactant. Relevant examples are considered and the results show that the triaxial Burke-Schumann flame can be substantially more complicated than the traditional Burke-Schumann flame. When the middle flow is inert the flame temperature is no longer constant but increases axially, reaching a maximum at the flame centerline. At the exit the flame does not sit on the tube exit but instead resides between the inner and outer tubes, resulting in an effective barrier for particle build-up on the burner rim. For the case of a third reactant in the middle flow, synthesis chemistry where the inner reaction is endothermic and the outer reaction is exothermic is considered. In addition to showing the flame temperature and flame shape, the results identify conditions wherein reaction is not possible due to insufficient heat transfer from the outer flame to support the inner flame reaction.

  13. Latitudinal Libration in a Triaxial Ellipsoid

    NASA Astrophysics Data System (ADS)

    Cebron, D.; Vantieghem, S.; Noir, J.

    2014-12-01

    As a consequence of gravitational coupling with their orbital partners, the rotational dynamics of planets and moons exhibits periodic variations in time, such as precession, libration and nutation. Moreover, most planets are subject to tidal forces, which in combination with the planet's rotation, result in a departure from a purely spherically symmetric object. In this theoretical-numerical study, we investigate the flows driven by latitudinal libration (i.e. an oscillation of the figure axis with respect to the mean rotation axis) within liquid cores of triaxial ellipsoidal shape. We first derive a uniform-vorticity solution for the equations of motion, and find that it can resonate with the spin-over inertial mode. Using a reduced model of viscosity (J. Noir and D. Cébron, J. Fluid Mech., vol. 737 (2013)), we deduce that the amplitude of the flow at resonance diverges as the inverse square-root of the Ekman number. Our results are consistent with previous studies in a spheroidal geometry (K. Zhang et al., J. Fluid Mech., vol. 696 (2012)). In a following step, we address the dynamical stability of this uniform-vorticity flow. We show that it is prone to inertial instabilities arising from a parametric resonance between two free inertial modes and the base flow. We also show that the vigor of the instability is governed by the frequency and two parameters that capture the dependence on the libration amplitude and geometry. The resonant nature of these phenomena suggests that libration in latitude, despite its small amplitude, may drive strong flows within planetary cores with possibly major implications for heat transport, dissipation and magnetic field generation/induction. This is discussed at planetary settings for the cores of the Moon, Io and Mercury, and the ancient lunar core.

  14. Triaxial rotor model description of quadrupole interference in collective nuclei: The P3 term

    NASA Astrophysics Data System (ADS)

    Allmond, J. M.; Wood, J. L.; Kulp, W. D.

    2009-08-01

    The triaxial rotor model with independent inertia and electric quadrupole tensors is applied to the P3 term, P3=<01||T̂(E2)||21><21||T̂(E2)||22><22||T̂(E2)||01>, which is a standard measure of quadrupole interference in collective nuclei. It is shown that the model naturally explains nuclei with anomalous signs for their P3 terms. Measurements of Q(21) in multiple-step Coulomb excitation can be significantly dependent on the sign of this term. The example of Pt194 is considered.

  15. Triaxial fiber optic magnetic field sensor for MRI applications

    NASA Astrophysics Data System (ADS)

    Filograno, Massimo L.; Pisco, Marco; Catalano, Angelo; Forte, Ernesto; Aiello, Marco; Soricelli, Andrea; Davino, Daniele; Visone, Ciro; Cutolo, Antonello; Cusano, Andrea

    2016-05-01

    In this paper, we report a fiber-optic triaxial magnetic field sensor, based on Fiber Bragg Gratings (FBGs) integrated with giant magnetostrictive material, the Terfenol-D. The realized sensor has been designed and engineered for Magnetic Resonance Imaging (MRI) applications. A full magneto-optical characterization of the triaxial sensing probe has been carried out, providing the complex relationship among the FBGs wavelength shift and the applied magnetostatic field vector. Finally, the developed fiber optic sensors have been arranged in a sensor network composed of 20 triaxial sensors for mapping the magnetic field distribution in a MRI-room at a diagnostic center in Naples (SDN), equipped with Positron emission tomography/magnetic resonance (PET/MR) instrumentation. Experimental results reveal that the proposed sensor network can be efficiently used in MRI centers for performing quality assurance tests, paving the way for novel integrated tools to measure the magnetic dose accumulated day by day by MRI operators.

  16. Fracture characteristics of PEEK at various stress triaxialities.

    PubMed

    Chen, Fei; Gatea, Shakir; Ou, Hengan; Lu, Bin; Long, Hui

    2016-12-01

    Polyether-ether-ketone (PEEK) is an alternative to metal alloys in orthopaedic applications. It gives significant advantages including excellent mechanical properties and non-toxicity. In this work, a set of specimens with different notched radii were selected to examine the effect of triaxial state of stress on the fracture behavior of PEEK. Fractographic analysis via scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX) further elucidated the fracture micromechanisms. Distinct fracture patterns were identified under different stress triaxialities. In addition, the microstructural inclusion properties in PEEK specimen such as inclusion size and chemical composition were analysed and determined. Finite element simulations were carried out to evaluate the correlation of observed fracture characteristics with different stress triaxialities. PMID:27498427

  17. Quasiequilibrium models for triaxially deformed rotating compact stars

    SciTech Connect

    Huang Xing; Markakis, Charalampos; Sugiyama, Noriyuki; Uryu, Koji

    2008-12-15

    Quasiequilibrium models of rapidly rotating triaxially deformed stars are computed in general relativistic gravity, assuming a conformally flat spatial geometry (Isenberg-Wilson-Mathews formulation) and a polytropic equation of state. Highly deformed solutions are calculated on the initial slice covered by spherical coordinate grids, centered at the source, in all angular directions up to a large truncation radius. Constant rest mass sequences are calculated from nearly axisymmetric to maximally deformed triaxial configurations. Selected parameters are to model (proto-) neutron stars; the compactness is M/R=0.001, 0.1, 0.14, and 0.2 for polytropic index n=0.3 and M/R=0.001, 0.1, 0.12, and 0.14 for n=0.5, where M/R refers to that of a nonrotating spherical star having the same rest mass. We confirmed that the triaxial solutions exist for these parameters as in the case of Newtonian polytropes. However, it is also found that the triaxial sequences become shorter for higher compactness, and those disappear at a certain large compactness for the n=0.5 case. In the scenario of the contraction of proto-neutron stars being subject to strong viscosity and rapid cooling, it is plausible that, once the viscosity driven secular instability sets in during the contraction, the proto-neutron stars are always maximally deformed triaxial configurations, as long as the compactness and the equation of state parameters allow such triaxial sequences. Detection of gravitational waves from such sources may be used as another probe for the nuclear equation of state.

  18. Expansion of the gravitational potential in triaxial ellipsoidal harmonics

    NASA Astrophysics Data System (ADS)

    Panou, G.; Delikaraoglou, D.

    2012-04-01

    Spherical harmonics have been extensively used in geodesy because they are relatively simple and the shape of the earth is nearly spherical. However, since the shape of the earth is closer to an ellipsoid of revolution, spheroidal harmonics have also been used. In modern geodesy, the triaxial ellipsoid as a generalization of the ellipsoid of revolution will have a significant role to play in studying the figure of the earth. In the era of outer space explorations, small bodies of the solar system are becoming the target of current and forthcoming space missions. These bodies have irregular shapes and the triaxial ellipsoid, being a genuine three-dimensional shape, provides a very good approximation. Thus, it might be expected that ellipsoidal harmonics, which are defined in a way similar to that of the spheroidal harmonics, would be even more suitable for the representation of the gravitational field of the earth, asteroids and comets. The purpose of the presentation is to discuss the theory of ellipsoidal harmonics and the basic background required to solve Dirichlet's boundary-value problem for a triaxial ellipsoid. We introduce triaxial ellipsoidal coordinates and we express Laplace's equation in these coordinates. By applying the method of separation of variables to Laplace's equation, the solution is obtained by solving Lamé's differential equation. For this reason, we present Lamé's functions in some detail. Using these functions, we formulate the ellipsoidal harmonics expansion of the gravitational potential in the exterior of a triaxial ellipsoid. Also, we show that the spherical and spheroidal harmonics can be produced as degenerated cases of the ellipsoidal harmonics. In spite of the fact that ellipsoidal harmonics are more complicated than spherical or spheroidal harmonics, they can be used in certain special cases which nevertheless are important, such as in modeling, for instance, the gravity field of a level triaxial ellipsoid.

  19. LOW GRADIENT PERMEABILITY MEASUREMENTS IN A TRIAXIAL SYSTEM.

    USGS Publications Warehouse

    Olsen, H.W.; Nichols, R.W.; Rice, T.L.

    1985-01-01

    Permeability measurements were conducted with the flow-pump method on sand, sandy silt and silty clay specimens in a conventional triaxial system by introducing and withdrawing water at known constant flow rates into the base of a specimen with a flow-pump, and by monitoring the head difference induced across the length of the specimen with a sensitive differential pressure transducer. The results show that the previously reported advantages of the flow-pump method, compared with conventional constant head and falling head methods, were realized for permeability measurements in conventional triaxial equipment.

  20. Likert Response Alternative Direction: SA to SD or SD to SA: Does It Make a Difference?

    ERIC Educational Resources Information Center

    Barnette, J. Jackson

    A 20-item survey was designed in 4 forms with response set direction as "strongly disagree" (SD) to "strongly agree" (SA) and SA to SD crossed with the absence or presence of negatively worded item stems. The primary research question related to finding a primacy effect when comparing the two response direction formats. Surveys were administered,…

  1. How UV photolysis accelerates the biodegradation and mineralization of sulfadiazine (SD).

    PubMed

    Pan, Shihui; Yan, Ning; Liu, Xinyue; Wang, Wenbing; Zhang, Yongming; Liu, Rui; Rittmann, Bruce E

    2014-11-01

    Sulfadiazine (SD), one of broad-spectrum antibiotics, exhibits limited biodegradation in wastewater treatment due to its chemical structure, which requires initial mono-oxygenation reactions to initiate its biodegradation. Intimately coupling UV photolysis with biodegradation, realized with the internal loop photobiodegradation reactor, accelerated SD biodegradation and mineralization by 35 and 71 %, respectively. The main organic products from photolysis were 2-aminopyrimidine (2-AP), p-aminobenzenesulfonic acid (ABS), and aniline (An), and an SD-photolysis pathway could be identified using C, N, and S balances. Adding An or ABS (but not 2-AP) into the SD solution during biodegradation experiments (no UV photolysis) gave SD removal and mineralization rates similar to intimately coupled photolysis and biodegradation. An SD biodegradation pathway, based on a diverse set of the experimental results, explains how the mineralization of ABS and An (but not 2-AP) provided internal electron carriers that accelerated the initial mono-oxygenation reactions of SD biodegradation. Thus, multiple lines of evidence support that the mechanism by which intimately coupled photolysis and biodegradation accelerated SD removal and mineralization was through producing co-substrates whose oxidation produced electron equivalents that stimulated the initial mono-oxygenation reactions for SD biodegradation.

  2. Method of using triaxial magnetic fields for making particle structures

    DOEpatents

    Martin, James E.; Anderson, Robert A.; Williamson, Rodney L.

    2005-01-18

    A method of producing three-dimensional particle structures with enhanced magnetic susceptibility in three dimensions by applying a triaxial energetic field to a magnetic particle suspension and subsequently stabilizing said particle structure. Combinations of direct current and alternating current fields in three dimensions produce particle gel structures, honeycomb structures, and foam-like structures.

  3. A Fiber Bragg Grating Sensing Based Triaxial Vibration Sensor.

    PubMed

    Li, Tianliang; Tan, Yuegang; Liu, Yi; Qu, Yongzhi; Liu, Mingyao; Zhou, Zude

    2015-01-01

    A fiber Bragg grating (FBG) sensing based triaxial vibration sensor has been presented in this paper. The optical fiber is directly employed as elastomer, and the triaxial vibration of a measured body can be obtained by two pairs of FBGs. A model of a triaxial vibration sensor as well as decoupling principles of triaxial vibration and experimental analyses are proposed. Experimental results show that: sensitivities of 86.9 pm/g, 971.8 pm/g and 154.7 pm/g for each orthogonal sensitive direction with linearity are separately 3.64%, 1.50% and 3.01%. The flat frequency ranges reside in 20-200 Hz, 3-20 Hz and 4-50 Hz, respectively; in addition, the resonant frequencies are separately 700 Hz, 40 Hz and 110 Hz in the x/y/z direction. When the sensor is excited in a single direction vibration, the outputs of sensor in the other two directions are consistent with the outputs in the non-working state. Therefore, it is effectively demonstrated that it can be used for three-dimensional vibration measurement. PMID:26393616

  4. A Fiber Bragg Grating Sensing Based Triaxial Vibration Sensor

    PubMed Central

    Li, Tianliang; Tan, Yuegang; Liu, Yi; Qu, Yongzhi; Liu, Mingyao; Zhou, Zude

    2015-01-01

    A fiber Bragg grating (FBG) sensing based triaxial vibration sensor has been presented in this paper. The optical fiber is directly employed as elastomer, and the triaxial vibration of a measured body can be obtained by two pairs of FBGs. A model of a triaxial vibration sensor as well as decoupling principles of triaxial vibration and experimental analyses are proposed. Experimental results show that: sensitivities of 86.9 pm/g, 971.8 pm/g and 154.7 pm/g for each orthogonal sensitive direction with linearity are separately 3.64%, 1.50% and 3.01%. The flat frequency ranges reside in 20–200 Hz, 3–20 Hz and 4–50 Hz, respectively; in addition, the resonant frequencies are separately 700 Hz, 40 Hz and 110 Hz in the x/y/z direction. When the sensor is excited in a single direction vibration, the outputs of sensor in the other two directions are consistent with the outputs in the non-working state. Therefore, it is effectively demonstrated that it can be used for three-dimensional vibration measurement. PMID:26393616

  5. Triaxiality of the ground states in the 174W

    NASA Astrophysics Data System (ADS)

    Ya, Tu; Chen, Y. S.; Liu, L.; Gao, Z. C.

    2016-05-01

    We have performed calculations for the ground states in 174W by using the projected total energy surface (PTES) calculations. Both the ground state (g.s.) band and its γ band reproduce the experimental data. Further discussion about the triaxiality in 174W has been made by transition quardrupole moment (Qt) and comparing between the PTES and TRS methods.

  6. Estimating Energy Expenditure with the RT3 Triaxial Accelerometer

    ERIC Educational Resources Information Center

    Maddison, Ralph; Jiang, Yannan; Vander Hoorn, Stephen; Mhurchu, Cliona Ni; Lawes, Carlene M. M.; Rodgers, Anthony; Rush, Elaine

    2009-01-01

    The RT3 is a relatively new triaxial accelerometer that has replaced the TriTrac. The aim of this study was to validate the RT3 against doubly labeled water (DLW) in a free-living, mixed weight sample of adults. Total energy expenditure (TEE) was measured over a 15-day period using DLW. Activity-related energy expenditure (AEE) was estimated by…

  7. A Fiber Bragg Grating Sensing Based Triaxial Vibration Sensor.

    PubMed

    Li, Tianliang; Tan, Yuegang; Liu, Yi; Qu, Yongzhi; Liu, Mingyao; Zhou, Zude

    2015-09-18

    A fiber Bragg grating (FBG) sensing based triaxial vibration sensor has been presented in this paper. The optical fiber is directly employed as elastomer, and the triaxial vibration of a measured body can be obtained by two pairs of FBGs. A model of a triaxial vibration sensor as well as decoupling principles of triaxial vibration and experimental analyses are proposed. Experimental results show that: sensitivities of 86.9 pm/g, 971.8 pm/g and 154.7 pm/g for each orthogonal sensitive direction with linearity are separately 3.64%, 1.50% and 3.01%. The flat frequency ranges reside in 20-200 Hz, 3-20 Hz and 4-50 Hz, respectively; in addition, the resonant frequencies are separately 700 Hz, 40 Hz and 110 Hz in the x/y/z direction. When the sensor is excited in a single direction vibration, the outputs of sensor in the other two directions are consistent with the outputs in the non-working state. Therefore, it is effectively demonstrated that it can be used for three-dimensional vibration measurement.

  8. Regularities of acoustic emission in coal samples under triaxial compression

    SciTech Connect

    Shkuratnik, V.L.; Filimonov, Y.L.; Kuchurin, S.V.

    2005-02-01

    The results are cited for the experimental study of acoustoemission processes in anthracite samples under triaxial compression by the Karman scheme at the constant rate of axial strain. From a comparison of the stress-strain and acoustoemission curves, the features of acoustic emission parameters in various deformation stages are revealed and the physicomechanical properties of coal are estimated.

  9. Triaxial Swirl Injector Element for Liquid-Fueled Engines

    NASA Technical Reports Server (NTRS)

    Muss, Jeff

    2010-01-01

    A triaxial injector is a single bi-propellant injection element located at the center of the injector body. The injector element consists of three nested, hydraulic swirl injectors. A small portion of the total fuel is injected through the central hydraulic injector, all of the oxidizer is injected through the middle concentric hydraulic swirl injector, and the balance of the fuel is injected through an outer concentric injection system. The configuration has been shown to provide good flame stabilization and the desired fuel-rich wall boundary condition. The injector design is well suited for preburner applications. Preburner injectors operate at extreme oxygen-to-fuel mass ratios, either very rich or very lean. The goal of a preburner is to create a uniform drive gas for the turbomachinery, while carefully controlling the temperature so as not to stress or damage turbine blades. The triaxial injector concept permits the lean propellant to be sandwiched between two layers of the rich propellant, while the hydraulic atomization characteristics of the swirl injectors promote interpropellant mixing and, ultimately, good combustion efficiency. This innovation is suited to a wide range of liquid oxidizer and liquid fuels, including hydrogen, methane, and kerosene. Prototype testing with the triaxial swirl injector demonstrated excellent injector and combustion chamber thermal compatibility and good combustion performance, both at levels far superior to a pintle injector. Initial testing with the prototype injector demonstrated over 96-percent combustion efficiency. The design showed excellent high -frequency combustion stability characteristics with oxygen and kerosene propellants. Unlike the more conventional pintle injector, there is not a large bluff body that must be cooled. The absence of a protruding center body enhances the thermal durability of the triaxial swirl injector. The hydraulic atomization characteristics of the innovation allow the design to be

  10. Development of Data Acquisition System for Consolidated Undrained Triaxial Test

    NASA Astrophysics Data System (ADS)

    Lee, L. M.; Yasuo, T.; Wei, L. C.; Yuan, L. C.

    2016-07-01

    Consolidated Undrained (CU) triaxial test is a common laboratory test used in practice for determining effective and total shear strength parameters of soil. This paper reported works carried out to develop a data acquisition system for a self-assembled triaxial machine. The developed system was capable of acquiring signals from the installed sensors (i.e. pressure transducer, load cell, LVDT), interpreting and presenting the data in real-time graphs. In addition, the study highlighted the advantages of performing double vacuuming method to saturate the soil specimen. The saturation can be obtained quicker and at a significantly lower cell pressure compared to the conventional stepwise increment of back pressure and cell pressure method.

  11. Variation after projection with a triaxially deformed nuclear mean field

    NASA Astrophysics Data System (ADS)

    Gao, Zao-Chun; Horoi, Mihai; Chen, Y. S.

    2015-12-01

    We implemented a variation after projection (VAP) algorithm based on a triaxially deformed Hartree-Fock-Bogoliubov vacuum state. This is the first projected mean field study that includes all the quantum numbers (except parity), i.e., spin (J ), isospin (T ), and mass number (A ). Systematic VAP calculations with JTA projection have been performed for the even-even s d -shell nuclei with the USDB Hamiltonian. All the VAP ground state energies are within 500 keV above the exact shell model values. Our VAP calculations show that the spin projection has two important effects: (1) the spin projection is crucial in achieving good approximation of the full shell model calculation; (2) the intrinsic shapes of the VAP wave functions with spin projection are always triaxial, while the Hartree-Fock-Bogoliubov methods likely provide axial intrinsic shapes. Finally, our analysis suggests that one may not be possible to associate an intrinsic shape to an exact shell model wave function.

  12. Triaxial strongly deformed bands in {sup 160,161}Tm

    SciTech Connect

    Teal, C.; Lagergren, K.; Aguilar, A.; Riley, M. A.; Hartley, D. J.; Simpson, J.; Joss, D. T.; Carpenter, M. P.; Janssens, R. V. F.; Lauritsen, T.; Lister, C. J.; Zhu, S.; Garg, U.; Kondev, F. G.; Wang, X.; Ragnarsson, I.

    2008-07-15

    High-spin states in {sup 160,161}Tm were populated using the {sup 128}Te({sup 37}Cl, 5n and 4n) reactions at a beam energy of 170 MeV. Emitted {gamma} rays were detected in the Gammasphere spectrometer. Two rotational bands with high moments of inertia were discovered, one assigned to {sup 160}Tm, while the other tentatively assigned to {sup 161}Tm. These sequences display features similar to bands observed in neighboring Er, Tm, Yb, and Lu nuclei which have been discussed in terms of triaxial strongly deformed structures. Cranked Nilsson Strutinsky calculations have been performed that predict well-deformed triaxial shapes at high spin in {sup 160,161}Tm.

  13. Failure in laboratory fault models in triaxial tests

    USGS Publications Warehouse

    Savage, J.C.; Lockner, D.A.; Byerlee, J.D.

    1996-01-01

    A model of a fault in the Earth is a sand-filled saw cut in a granite cylinder subjected to a triaxial test. The saw cut is inclined at an angle a to the cylinder axis, and the sand filling is intended to represent gouge. The triaxial test subjects the granite cylinder to a constant confining pressure and increasing axial stress to maintain a constant rate of shortening of the cylinder. The required axial stress increases at a decreasing rate to a maximum, beyond which a roughly constant axial stress is sufficient to maintain the constant rate of shortening: Such triaxial tests were run for saw cuts inclined at angles ?? of 20??, 25??, 30??, 35??, 40??, 45??, and 50?? to the cylinder axis, and the apparent coefficient of friction ??a (ratio of the shear stress to the normal stress, both stresses resolved onto the saw cut) at failure was determined. Subject to the assumption that the observed failure involves slip on Coulomb shears (orientation unspecified), the orientation of the principal compression axis within the gouge can be calculated as a function of ??a for a given value of the coefficient of internal friction ??i. The rotation of the principal stress axes within the gouge in a triaxial test can then be followed as the shear strain across the gouge layer increases. For ??i ??? 0.8, an appropriate value for highly sheared sand, the observed values ??a imply that the principal-axis of compression within the gouge rotates so as to approach being parallel to the cylinder axis for all saw cut angles (20?? < ?? < 50??). In the limiting state (principal compression axis parallel to cylinder axis) the stress state in the gouge layer would be the same as that in the granite cylinder, and the failure criterion would be independent of the saw cut angle.

  14. Mechanical Properties of Triaxial Braided Carbon/Epoxy Composites

    NASA Technical Reports Server (NTRS)

    Bowman, C. L.; Roberts, G. D.; Braley, M. S.; Xie, M.; Booker, M. J.

    2003-01-01

    In an on-going effort to increase the safety and efficiency of turbine engines, the National Aeronautics and Space Administration is exploring lightweight alternatives to the metal containment structures that currently encase commercial jet engines. Epoxy reinforced with braided carbon fibers is a candidate structural material which may be suitable for an engine case. This paper reports flat-coupon mechanical-property experiments performed to compliment previously reported subcomponent impact testing and analytical simulation of containment structures. Triaxial-braid T700/5208 epoxy and triaxial-braid T700/M36 toughened epoxy composites were evaluated. Also, two triaxial-braid architectures (0 +/- 60 deg., 0 +/- 45 deg.) with the M36 resin were evaluated through tension, compression, and shear testing. Tensile behavior was compared between standard straight-sided specimens (ASTM D3039) and bowtie specimens. Both double-notch shear (ASTM D3846) and Iosepescu (ASTM D5379) tests were performed as well. The M36/0 +/- 45 deg. configuration yield the best response when measurements were made parallel to the axial tows. Conversely, the M36/0 +/- 60 deg. configuration was best when measurements were made perpendicular to the axial tows. The results were used to identify critical properties and to augment the analysis of impact experiments.

  15. Mechanical Properties of Triaxial Braided Carbon/Epoxy Composites

    NASA Technical Reports Server (NTRS)

    Bowman, C. L.; Roberts, G. D.; Braley, M. S.; Xie, M.; Booker, M. J.

    2003-01-01

    In an on-going effort to increase the safety and efficiency of turbine engines, the National Aeronautics and Space Administration is exploring lightweight alternatives to the metal containment structures that currently encase commercial jet engines. Epoxy reinforced with braided carbon fibers is a candidate structural material which may be suitable for an engine case. This paper reports flat-coupon mechanical-property experiments performed to compliment previously reported subcomponent impact testing and analytical simulation of containment structures. Triaxial-braid T700/5208 epoxy and triaxial-braid T700h436 toughened epoxy composites were evaluated. Also, two triaxial-braid architectures (0 degrees plus or minus 60 degrees, and 0 degrees plus or minus 45 degrees) with the M36 resin were evaluated through tension, compression, and shear testing. Tensile behavior was compared between standard straight-sided specimens (ASTM D3039) and bow-tie specimens. Both double-notch shear (ASTM D3846) and Iosepescu (ASTM D5379) tests were performed as well. The M36/O degrees plus or minus 45 degrees configuration yield the best response when measurements were made parallel to the axial tows. Conversely, the M36/0 degrees plus or minus 60 degrees configuration was best when measurements were made perpendicular to the axial tows. The results were used to identify critical properties and to augment the analysis of impact experiments.

  16. Using triaxial magnetic fields to create high susceptibility particle composites.

    PubMed

    Martin, James E; Venturini, Eugene; Gulley, Gerald L; Williamson, Jonathan

    2004-02-01

    We report on the use of triaxial magnetic fields to create a variety of isotropic and anisotropic magnetic particle/polymer composites with significantly enhanced magnetic susceptibilities. A triaxial field is a superposition of three orthogonal ac magnetic fields, each generated by a Helmholtz coil in series resonance with a tunable capacitor bank. Field frequencies are in the range of 150-400 Hz. Because both the field amplitudes and frequencies can be varied, a rich variety of structures can be created. Perhaps the most unusual effects occur when either two or three of the field components are heterodyned to give beat frequencies on the order of 1 Hz. This leads to a striking particle dynamics that evolves into surprising structures during resin gelation. These structures are found to have perhaps the highest susceptibility that a particle composite can have. The susceptibility anisotropy of these composites can be controlled over a wide range by judicious adjustment of the relative field amplitudes. These experimental data are supported by large-scale Brownian dynamics simulations of the complex many-body interactions that occur in triaxial magnetic fields. These simulations show that athermal three-dimensional field heterodyning leads to structures with a susceptibility that is as high as that achieved with thermal annealing. Thus with coherent particle motions we can achieve magnetostatic energies that are quite close to the ground state. PMID:14995450

  17. Experimental study of upper sd shell nuclei and evolution of sd-fp shell gap

    SciTech Connect

    Sarkar, M. Saha

    2012-06-27

    The intruder orbitals from the fp shell play important role in the structure of nuclei around the line of stability in the upper sd shell. Experimentally we have studied {sup 35}Cl, {sup 30}P, {sup 36}Cl, {sup 37}Ar and {sup 34}Cl in this mass region using the INGA setup. Large basis cross-shell shell model calculations have indicated the need for change of the sd-fp energy gap for reliable reproduction of negative parity and high spin positive parity states. Indication of population of states of large deformation has been found in our data. Theoretical interpretation of these states has been discussed.

  18. Understanding nuclei in the upper sd - shell

    SciTech Connect

    Sarkar, M. Saha; Bisoi, Abhijit; Ray, Sudatta; Kshetri, Ritesh; Sarkar, S.

    2014-08-14

    Nuclei in the upper-sd shell usually exhibit characteristics of spherical single particle excitations. In the recent years, employment of sophisticated techniques of gamma spectroscopy has led to observation of high spin states of several nuclei near A ≃ 40. In a few of them multiparticle, multihole rotational states coexist with states of single particle nature. We have studied a few nuclei in this mass region experimentally, using various campaigns of the Indian National Gamma Array setup. We have compared and combined our empirical observations with the large-scale shell model results to interpret the structure of these nuclei. Indication of population of states of large deformation has been found in our data. This gives us an opportunity to investigate the interplay of single particle and collective degrees of freedom in this mass region.

  19. Triaxial rotor model description of quadrupole interference in collective nuclei: The P{sub 3} term

    SciTech Connect

    Allmond, J. M.; Wood, J. L.; Kulp, W. D.

    2009-08-15

    The triaxial rotor model with independent inertia and electric quadrupole tensors is applied to the P{sub 3} term, P{sub 3}=<0{sub 1}||T(E2)||2{sub 1}><2{sub 1}||T(E2)||2{sub 2}><2{sub 2}||T(E2)||0{sub 1}>, which is a standard measure of quadrupole interference in collective nuclei. It is shown that the model naturally explains nuclei with anomalous signs for their P{sub 3} terms. Measurements of Q(2{sub 1}) in multiple-step Coulomb excitation can be significantly dependent on the sign of this term. The example of {sup 194}Pt is considered.

  20. Cytogenetic Analysis of an SD Chromosome from a Natural Population of DROSOPHILA MELANOGASTER

    PubMed Central

    Trippa, G.; Loverre, A.; Cicchetti, R.

    1980-01-01

    The discovery and the cytogenetic characterization of a new SD (Segregation Distorter) chromosome 2 from a natural population in Ranna (Sicily, Italy), SDRa, are reported. The main features of this chromosome are as follows: (a) it contains an SdRa gene with a moderate degree of segregation distortion (k = 0.72), (b) a recessive female sterile gene, fs(2)TLM, responsible for modifications of the morphology and structure of the tests and ovaries is located at 89.7, (c) SDRa/SDRa males and females are viable but sterile, the females due to homozygosis of fs(2)TLM and the males because of homozygosis of a region containing the Sd locus, and (d) SDi/SDj combinations are fertile, thus suggesting that the different Sd factors found in natural populations constitute a multiple allelic series.—These data may indicate that each population containing SD chromosomes has evolved its own genetic architecture for the complex SD system, with specific modifiers and perhaps different Sd genes. The possibility of reconstructing the evolutionary pattern of the SDRa chromosome in the natural Ranna population after the model of Charlesworth and Hartl (1978) and Crow (1979) is considered. PMID:17249043

  1. Temperature as a predictive tool for plantar triaxial loading.

    PubMed

    Yavuz, Metin; Brem, Ryan W; Davis, Brian L; Patel, Jalpa; Osbourne, Abe; Matassini, Megan R; Wood, David A; Nwokolo, Irene O

    2014-11-28

    Diabetic foot ulcers are caused by moderate repetitive plantar stresses in the presence of peripheral neuropathy. In severe cases, the development of these foot ulcers can lead to lower extremity amputations. Plantar pressure measurements have been considered a capable predictor of ulceration sites in the past, but some investigations have pointed out inconsistencies when solely relying on this method. The other component of ground reaction forces/stresses, shear, has been understudied due to a lack of adequate equipment. Recent articles reported the potential clinical significance of shear in diabetic ulcer etiology. With the lack of adequate tools, plantar temperature has been used as an alternative method for determining plantar triaxial loading and/or shear. However, this method has not been previously validated. The purpose of this study was to analyze the potential association between exercise-induced plantar temperature increase and plantar stresses. Thirteen healthy individuals walked on a treadmill for 10 minutes at 3.2km/h. Pre and post-exercise temperature profiles were obtained with a thermal camera. Plantar triaxial stresses were quantified with a custom-built stress plate. A statistically significant correlation was observed between peak shear stress (PSS) and temperature increase (r=0.78), but not between peak resultant stress (PRS) and temperature increase (r=0.46). Plantar temperature increase could predict the location of PSS and PRS in 23% and 39% of the subjects, respectively. Only a moderate linear relationship was established between triaxial plantar stresses and walking-induced temperature increase. Future research will investigate the value of nonlinear models in predicting plantar loading through foot temperature. PMID:25446272

  2. A self-consistent study of triaxial black hole nuclei

    NASA Astrophysics Data System (ADS)

    Poon, Ming Yan

    Knowledge of the three-dimensional shapes of elliptical galaxies has not advanced much since the time of Edwin Hubble. Elliptical galaxies are still classified according to their luminosity distributions and the isophotal contour shapes of their two-dimensional images projected on the sky. Their intrinsic shapes could be oblate, prolate, or fully triaxial, since all such shapes produce perfectly elliptical contours on projection. One way to constrain the possible 3D shapes of elliptical galaxies is to attempt to construct self-consistent dynamical models with various shapes. In this study, models were constructed of the central regions (“nuclei”) of elliptical galaxies. Observed nuclei have a power-law dependence of stellar density on radius, and universally contain a single supermassive black hole at their center, with mass ˜106 109 M⊙ . At low energies in such nuclei, the motion was found to be essentially regular, i.e. non-chaotic; the gravitational potential can be considered as a perturbation to the integrable Keplerian potential. At higher energies, where the enclosed stellar mass is a few times the black hole mass, the black hole renders those orbits that come close to the black hole stochastic. This transition to global stochasticity is rapid and occurs at lower energies in more elongated nuclei. The self-consistency of triaxial models of black hole nuclei was demonstrated by using Schwarzschild's method to construct self-consistent orbital superpositions representing nuclei with different shapes. N-body integrations of Monte-Carlo realizations of the Schwarzschild solutions showed that some of these nuclei are stable; nearly prolate nuclei were found to be unstable, and they evolve rapidly to axisymmetric shapes. The possibility that nuclei may be triaxial in shape complicates the interpretation of stellar kinematical data from the centers of galaxies and may alter the inferred interaction rates between stars and supermassive black holes.

  3. Final report of the safety assessment of Alcohol Denat., including SD Alcohol 3-A, SD Alcohol 30, SD Alcohol 39, SD Alcohol 39-B, SD Alcohol 39-C, SD Alcohol 40, SD Alcohol 40-B, and SD Alcohol 40-C, and the denaturants, Quassin, Brucine Sulfate/Brucine, and Denatonium Benzoate.

    PubMed

    2008-01-01

    Alcohol Denat. is the generic term used by the cosmetics industry to describe denatured alcohol. Alcohol Denat. and various specially denatured (SD) alcohols are used as cosmetic ingredients in a wide variety of products. Many denaturants have been previously considered, on an individual basis, as cosmetic ingredients by the Cosmetic Ingredient Review (CIR) Expert Panel, whereas others, including Brucine and Brucine Sulfate, Denatonium Benzoate, and Quassin, have not previously been evaluated. Quassin is a bitter alkaloid obtained from the wood of Quassia amara. Quassin has been used as an insect antifeedant and insecticide and several studies demonstrate its effectiveness. At oral doses up to 1000 mg/kg using rats, Quassin was not toxic in acute and short-term tests, but some reversible piloerection, decrease in motor activity, and a partial loss of righting reflex were found in mice at 500 mg/kg. At 1000 mg/kg given intraperitoneally (i.p.), all mice died within 24 h of receiving treatment. In a cytotoxicity test with brine shrimp, 1 mg/ml of Quassin did not possess any cytotoxic or antiplasmodial activity. Quassin administered to rat Leydig cells in vitro at concentrations of 5-25 ng/ml inhibited both the basal and luteinizing hormone (LH)-stimulated testosterone secretion in a dose-related fashion. Quassin at doses up to 2.0 g/kg in drinking water using rats produced no significant effect on the body weights, but the mean weights of the testes, seminal vesicles, and epididymides were significantly reduced, and the weights of the anterior pituitary glands were significantly increased. The sperm counts and levels of LH, follicle-stimulating hormone (FSH), and testosterone were significantly lower in groups treated with Quassin. Brucine is a derivative of 2-hydroxystrychnine. Swiss-Webster mice given Brucine base, 30 ml/kg, had an acute oral LD(50) of 150 mg/kg, with central nervous system depression followed by convulsions and seizures in some cases. In those

  4. Shape coexistence and triaxiality in nuclei near 80Zr

    NASA Astrophysics Data System (ADS)

    Zheng, S. J.; Xu, F. R.; Shen, S. F.; Liu, H. L.; Wyss, R.; Yan, Y. P.

    2014-12-01

    Total-Routhian-surface calculations have been performed to investigate the shape evolutions of A ˜80 nuclei: Zr-8480,Sr-8076 , and Mo,8684 . Shape coexistences of spherical, prolate, and oblate deformations have been found in these nuclei. Particularly for the nuclei 80Sr and 82Zr , the energy differences between two shape-coexisting states are less than 220 keV. At high spins, the g9 /2 shell plays an important role in shape evolutions. It has been found that the alignment of the g9 /2 quasiparticles drives nuclei to be triaxial.

  5. Eigenmodes of triaxial ellipsoidal acoustical cavities with mixed boundary conditions

    NASA Astrophysics Data System (ADS)

    Willatzen, M.; Lew Yan Voon, L. C.

    2004-12-01

    The linear acoustics problem of resonant vibrational modes in a triaxial ellipsoidal acoustic cavity with walls of arbitrary acoustic impedance has been quasi-analytically solved using the Frobenius power-series expansion method. Eigenmode results are presented for the lowest two eigenmodes in cases with pressure-release, rigid-wall, and lossy-wall boundary conditions. A mode crossing is obtained as a function of the specific acoustic impedance of the wall; the degeneracy is not symmetry related. Furthermore, the damping of the wave is found to be maximal near the crossing. .

  6. Rotation and wobbling motion in triaxially deformed nuclei

    SciTech Connect

    Kaneko, K. )

    1992-06-01

    A quantum mechanical method of rotation and wobbling motion in triaxially deformed nuclei is represented within the framework of time-dependent Hartree-Fock theory. For such systems, the intrinsic frame is defined by imposing constraints of principal-axis frame. With aid of the canonical formulation of the constrained system, the Dirac quantization of the classical system is performed. It is shown that the commutation relations of angular momentum in the intrinsic frame then exactly satisfy the body-fixed frame. Furthermore, a method of describing large amplitude collective motion in the constrained system is proposed by extending the self-consistent collective-coordinate method.

  7. Parametric design of tri-axial nested Helmholtz coils

    SciTech Connect

    Abbott, Jake J.

    2015-05-15

    This paper provides an optimal parametric design for tri-axial nested Helmholtz coils, which are used to generate a uniform magnetic field with controllable magnitude and direction. Circular and square coils, both with square cross section, are considered. Practical considerations such as wire selection, wire-wrapping efficiency, wire bending radius, choice of power supply, and inductance and time response are included. Using the equations provided, a designer can quickly create an optimal set of custom coils to generate a specified field magnitude in the uniform-field region while maintaining specified accessibility to the central workspace. An example case study is included.

  8. TRIAXIAL AND SHEAR TESTING OF SELECTED BACKFILL MATERIALS

    SciTech Connect

    N. E. Kramer

    2000-08-07

    The Subsurface Performance Testing Section is performing tests in the Department of Energy's Atlas Facility to evaluate the performance of various backfill materials. Triaxial and shear tests were conducted on select backfill materials. The specific materials tested were: crushed tuff, overton sand, 4- 10 silica sand, 1/4'' dolostone/marble, and limestone. The objective of this report is to provide an estimated value for Poisson's ratio, determine internal friction angle, and stress-strain modulus of the backfill materials that were tested. These basic parameters are necessary for the selection of a backfill material to be included in the repository. This report transmits the results in both hardcopy and electronic formats plus describes the methodology and interpretation of the results. No conclusions will be drawn about the test results, as this will be the purview of other reports. The scope of this report is to use the triaxial and shear testing information and calculate, the internal friction angle, stress-strain modulus, and provide an estimate of Poisson's ratio (Sowers 1979, p. 199) of the selected backfill materials. Standard laboratory procedures, mentioned in Section 2 of this report, were used.

  9. Principal Components Analysis of Triaxial Vibration Data From Helicopter Transmissions

    NASA Technical Reports Server (NTRS)

    Tumer, Irem Y.; Huff, Edward M.

    2001-01-01

    Research on the nature of the vibration data collected from helicopter transmissions during flight experiments has led to several crucial observations believed to be responsible for the high rates of false alarms and missed detections in aircraft vibration monitoring systems. This work focuses on one such finding, namely, the need to consider additional sources of information about system vibrations. In this light, helicopter transmission vibration data, collected using triaxial accelerometers, were explored in three different directions, analyzed for content, and then combined using Principal Components Analysis (PCA) to analyze changes in directionality. In this paper, the PCA transformation is applied to 176 test conditions/data sets collected from an OH58C helicopter to derive the overall experiment-wide covariance matrix and its principal eigenvectors. The experiment-wide eigenvectors. are then projected onto the individual test conditions to evaluate changes and similarities in their directionality based on the various experimental factors. The paper will present the foundations of the proposed approach, addressing the question of whether experiment-wide eigenvectors accurately model the vibration modes in individual test conditions. The results will further determine the value of using directionality and triaxial accelerometers for vibration monitoring and anomaly detection.

  10. Triaxial HTS Cable for the AEP Bixby Project

    SciTech Connect

    Demko, Jonathan A; Gouge, Michael J; Lindsay, David T; Roden, Mark L; Tolbert, Jerry Carlton

    2007-01-01

    Ultera has installed a single 200-meter long high temperature superconducting (HTS) 3-phase triaxial design cable at the American Electric Power (AEP) Bixby substation in Columbus, Ohio. The cable connects a 132/13.8 kV transformer to the distribution switchgear serving seven outgoing circuits. It was designed to carry 3000 Arms. Testing of 3- to 5-meter length prototype cables, including a 5-meter prototype with full scale terminations tested at ORNL was conducted prior to the manufacture and installation of the AEP triaxial cable. These prototypes were used to demonstrate the crucial operating conditions including steady state operation at the 3000 Arms design current, high voltage operation, high voltage withstand and 110 kV impulse, and overcurrent fault capability. A summary of the results from the thermal analysis and testing conducted by Ultera and ORNL will be presented. Some analysis of the cable thermal-hydraulic response based on the testing that were used to determine some of the cable cryogenic system requirements are also presented.

  11. Stellar spiral structures in triaxial dark matter haloes

    NASA Astrophysics Data System (ADS)

    Hu, Shaoran; Sijacki, Debora

    2016-09-01

    We employ very high resolution simulations of isolated Milky Way-like galaxies to study the effect of triaxial dark matter haloes on exponential stellar discs. Non-adiabatic halo shape changes can trigger two-armed grand-design spiral structures which extend all the way to the edge of the disc. Their pattern speed coincides with the inner Lindblad resonance indicating that they are kinematic density waves which can persist up to several Gyr. In dynamically cold discs, grand-design spirals are swing amplified and after a few Gyr can lead to the formation of (multi-armed) transient recurrent spirals. Stellar discs misaligned to the principal planes of the host triaxial halo develop characteristic integral shaped warps, but otherwise exhibit very similar spiral structures as aligned discs. For the grand-design spirals in our simulations, their strength dependence with radius is determined by the torque on the disc, suggesting that by studying grand-design spirals without bars it may be possible to set constraints on the tidal field and host dark matter halo shape.

  12. Characterization of Triaxial Braided Composite Material Properties for Impact Simulation

    NASA Technical Reports Server (NTRS)

    Roberts, Gary D.; Goldberg, Robert K.; Biniendak, Wieslaw K.; Arnold, William A.; Littell, Justin D.; Kohlman, Lee W.

    2009-01-01

    The reliability of impact simulations for aircraft components made with triaxial braided carbon fiber composites is currently limited by inadequate material property data and lack of validated material models for analysis. Improvements to standard quasi-static test methods are needed to account for the large unit cell size and localized damage within the unit cell. The deformation and damage of a triaxial braided composite material was examined using standard quasi-static in-plane tension, compression, and shear tests. Some modifications to standard test specimen geometries are suggested, and methods for measuring the local strain at the onset of failure within the braid unit cell are presented. Deformation and damage at higher strain rates is examined using ballistic impact tests on 61- by 61- by 3.2-mm (24- by 24- by 0.125-in.) composite panels. Digital image correlation techniques were used to examine full-field deformation and damage during both quasi-static and impact tests. An impact analysis method is presented that utilizes both local and global deformation and failure information from the quasi-static tests as input for impact simulations. Improvements that are needed in test and analysis methods for better predictive capability are examined.

  13. Characterization of Damage in Triaxial Braid Composites Under Tensile Loading

    NASA Technical Reports Server (NTRS)

    Littell, Justin D.; Binienda, Wieslaw K.; Roberts, Gary D.; Goldberg, Robert K.

    2009-01-01

    Carbon fiber composites utilizing flattened, large tow yarns in woven or braided forms are being used in many aerospace applications. Their complex fiber architecture and large unit cell size present challenges in both understanding deformation processes and measuring reliable material properties. This report examines composites made using flattened 12k and 24k standard modulus carbon fiber yarns in a 0 /+60 /-60 triaxial braid architecture. Standard straight-sided tensile coupons are tested with the 0 axial braid fibers either parallel with or perpendicular to the applied tensile load (axial or transverse tensile test, respectively). Nonuniform surface strain resulting from the triaxial braid architecture is examined using photogrammetry. Local regions of high strain concentration are examined to identify where failure initiates and to determine the local strain at the time of initiation. Splitting within fiber bundles is the first failure mode observed at low to intermediate strains. For axial tensile tests splitting is primarily in the 60 bias fibers, which were oriented 60 to the applied load. At higher strains, out-of-plane deformation associated with localized delamination between fiber bundles or damage within fiber bundles is observed. For transverse tensile tests, the splitting is primarily in the 0 axial fibers, which were oriented transverse to the applied load. The initiation and accumulation of local damage causes the global transverse stress-strain curves to become nonlinear and causes failure to occur at a reduced ultimate strain. Extensive delamination at the specimen edges is also observed.

  14. Single particle calculations for a Woods-Saxon potential with triaxial deformations, and large Cartesian oscillator basis (TRIAXIAL 2014, Third version of the code Triaxial)

    NASA Astrophysics Data System (ADS)

    Mohammed-Azizi, B.; Medjadi, D. E.

    2014-11-01

    Theory and FORTRAN program of the first version of this code (TRIAXIAL) have already been described in detail in Computer Physics Comm. 156 (2004) 241-282. A second version of this code (TRIAXIAL 2007) has been given in CPC 176 (2007) 634-635. The present FORTRAN program is the third version (TRIAXIAL 2014) of the same code. Now, It is written in free format. As the former versions, this FORTRAN program solves the same Schrodinger equation of the independent particle model of the atomic nucleus with the same method. However, the present version is much more convenient. In effect, it is characterized by the fact that the eigenvalues and the eigenfunctions can be given by specific subroutines. The latters did not exist in the old versions (2004 and 2007). In addition, it is to be noted that in the previous versions, the eigenfunctions were only given by their coefficients of their expansion onto the harmonic oscillator basis. This method is needed in some cases. But in other cases, it is preferable to treat the eigenfunctions directly in configuration space. For this reason, we have implemented an additional subroutine for this task. Some other practical subroutines have also been implemented. Moreover, eigenvalues and eigenfunctions are recorded onto several files. All these new features of the code and some important aspects of its structure are explained in the document ‘Triaxial2014 use.pdf’. Catalogue identifier: ADSK_v3_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADSK_v3_0.html Program obtainable from: CPC Program Library, Queen’s University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 13672 No. of bytes in distributed program, including test data, etc.: 217598 Distribution format: tar.gz Programming language: FORTRAN 77/90 (double precision). Computer: PC. Pentium 4, 2600MHz and beyond. Operating system: WINDOWS XP

  15. Single particle calculations for a Woods-Saxon potential with triaxial deformations, and large Cartesian oscillator basis (TRIAXIAL 2014, Third version of the code Triaxial)

    NASA Astrophysics Data System (ADS)

    Mohammed-Azizi, B.; Medjadi, D. E.

    2014-11-01

    Theory and FORTRAN program of the first version of this code (TRIAXIAL) have already been described in detail in Computer Physics Comm. 156 (2004) 241-282. A second version of this code (TRIAXIAL 2007) has been given in CPC 176 (2007) 634-635. The present FORTRAN program is the third version (TRIAXIAL 2014) of the same code. Now, It is written in free format. As the former versions, this FORTRAN program solves the same Schrodinger equation of the independent particle model of the atomic nucleus with the same method. However, the present version is much more convenient. In effect, it is characterized by the fact that the eigenvalues and the eigenfunctions can be given by specific subroutines. The latters did not exist in the old versions (2004 and 2007). In addition, it is to be noted that in the previous versions, the eigenfunctions were only given by their coefficients of their expansion onto the harmonic oscillator basis. This method is needed in some cases. But in other cases, it is preferable to treat the eigenfunctions directly in configuration space. For this reason, we have implemented an additional subroutine for this task. Some other practical subroutines have also been implemented. Moreover, eigenvalues and eigenfunctions are recorded onto several files. All these new features of the code and some important aspects of its structure are explained in the document ‘Triaxial2014 use.pdf’. Catalogue identifier: ADSK_v3_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADSK_v3_0.html Program obtainable from: CPC Program Library, Queen’s University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 13672 No. of bytes in distributed program, including test data, etc.: 217598 Distribution format: tar.gz Programming language: FORTRAN 77/90 (double precision). Computer: PC. Pentium 4, 2600MHz and beyond. Operating system: WINDOWS XP

  16. Brittle Failure of a Compactive Porous Sandstone under True Triaxial Conventional and Novel Stress Paths

    NASA Astrophysics Data System (ADS)

    Ma, X.; Haimson, B.

    2011-12-01

    We conducted two series of true triaxial tests in Coconino Sandstone (17.5% porosity; 96% quartz), in which square cuboidal rock specimens (19 x 19 x 38mm) were independently compressed in three principal directions, using the UW-Madison true triaxial testing apparatus. In the conventional series of true triaxial tests the least and intermediate principal stresses (σ3 and σ2) were maintained constant, while the largest stress (σ1) was raised at a rate of 0.1 MPa/s until brittle failure occurred in the form of shear fracture or fault. Eight different σ3 levels were attempted (between 0 and 150 MPa), to cover the full range of brittle behavior up to the point of brittle-ductile transition. σ2 varied between σ2 = σ3 and σ2 = σ1. The results reinforced previous findings in crystalline rocks that both resistance to faulting and fault angle increase as σ2 rises above σ3 (Haimson and Chang, 2000; Chang and Haimson, 2000), albeit at a reduced rate. This is contrary to the Mohr-Coulomb model, which predicts no σ2 effect on either. Plotting all the data points as τoct vs. σoct (where τoct is the octahedral shear stress and σoct is the mean normal stress, both at fault initiation) reveals a trend that can be loosely fitted by a quadratic equation (R = 0.95). A better fit is obtained if the mean stress σoct is reduced to its 2D equivalent (σ1+σ3)/2 (R = 0.99). Brittle failure characteristics varied from single fault at σ3 lower than 120 MPa, to multiple parallel and conjugate faults at σ3 = 120-150 MPa (a characteristic of brittle-ductile transition, Paterson and Wong, 2005). Conventional true triaxial tests, however, do not maintain constant any of the three principal stress invariants during loading. Tests using a novel loading path with fixed deviatoric stress state facilitate comparison with a theory that predicts failure as a bifurcation from homogeneous deformation (Rudnicki and Rice, 1975). We conducted a series of tests in which σ3 (between 0 and

  17. Strain limit dependence on stress triaxiality for pressure vessel steel

    NASA Astrophysics Data System (ADS)

    Deng, Y.-C.; Chen, G.; Yang, X.-F.; Xu, T.

    2009-08-01

    In this paper, the failure characteristics of pressure vessel materials were investigated, and measurement and analysis approaches for ductile fracture strains were studied. Based on uniaxial tensile tests of notched round bar specimens, combined with finite element analyses and microscopic observations of fracture surface, the relationships between the stress triaxiality factor and the ductile fracture strain are proposed for three typical Chinese pressure vessel steels, 16MnR, Q235 and 0Cr18Ni9. The comparison of experimental fracture strains with the multiaxial strain limit specified in ASME VIII-2 2007 shows that the strain limit criterion of ASME is suitable for carbon steels but not suitable for austenitic stainless steels for Chinese pressure vessel steels. To improve the calculation accuracy for fracture strain of materials and to develop the strain limit criterion for Chinese pressure vessel materials, more experimental studies and numerical analyses on fracture strain are necessary.

  18. Robust adaptive control of MEMS triaxial gyroscope using fuzzy compensator.

    PubMed

    Fei, Juntao; Zhou, Jian

    2012-12-01

    In this paper, a robust adaptive control strategy using a fuzzy compensator for MEMS triaxial gyroscope, which has system nonlinearities, including model uncertainties and external disturbances, is proposed. A fuzzy logic controller that could compensate for the model uncertainties and external disturbances is incorporated into the adaptive control scheme in the Lyapunov framework. The proposed adaptive fuzzy controller can guarantee the convergence and asymptotical stability of the closed-loop system. The proposed adaptive fuzzy control strategy does not depend on accurate mathematical models, which simplifies the design procedure. The innovative development of intelligent control methods incorporated with conventional control for the MEMS gyroscope is derived with the strict theoretical proof of the Lyapunov stability. Numerical simulations are investigated to verify the effectiveness of the proposed adaptive fuzzy control scheme and demonstrate the satisfactory tracking performance and robustness against model uncertainties and external disturbances compared with conventional adaptive control method.

  19. Triaxial thermopile array geo-heat-flow sensor

    DOEpatents

    Carrigan, Charles R.; Hardee, Harry C.; Reynolds, Gerald D.; Steinfort, Terry D.

    1992-01-01

    A triaxial thermopile array geothermal heat flow sensor is designed to measure heat flow in three dimensions in a reconstituted or unperturbed subsurface regime. Heat flow can be measured in conductive or permeable convective media. The sensor may be encased in protective pvc tubing and includes a plurality of thermistors and an array of heat flow transducers arranged in a vertical string. The transducers produce voltage proportional to heat flux along the subsurface regime and permit direct measurement of heat flow in the subsurface regime. The presence of the thermistor array permits a comparison to be made between the heat flow estimates obtained from the transducers and heat flow calculated using temperature differences and Fourier's Law. The device is extremely sensitive with an accuracy of less than 0.1 Heat Flow Units (HFU) and may be used for long term readings.

  20. Triaxial thermopile array geo-heat-flow sensor

    DOEpatents

    Carrigan, C.R.; Hardee, H.C.; Reynolds, G.D.; Steinfort, T.D.

    1990-01-01

    A triaxial thermopile array geothermal heat flow sensor is designed to measure heat flow in three dimensions in a reconstituted or unperturbed subsurface regime. Heat flow can be measured in conductive or permeable convective media. The sensor may be encased in protective pvc tubing and includes a plurality of thermistors and an array of heat flow transducers produce voltage proportional to heat flux along the subsurface regime and permit direct measurement of heat flow in the subsurface regime. The presence of the thermistor array permits a comparison to be made between the heat flow estimates obtained from the transducers and heat flow calculated using temperature differences and Fourier's Law. The device is extremely sensitive with an accuracy of less than 0.1 Heat Flow Units (HFU) and may be used for long term readings. 6 figs.

  1. Characteristics of dynamic triaxial testing of asphalt mixtures

    NASA Astrophysics Data System (ADS)

    Ulloa Calderon, Alvaro

    Due to the increasing traffic loads and tire pressures, a serious detrimental impact has occurred on flexible pavements in the form of excessive permanent deformation once the critical combination of loading and environmental conditions are reached. This distress, also known as rutting, leads to an increase in road roughness and ultimately jeopardizes the road users' safety. The flow number (FN) simple performance test for asphalt mixtures was one of the final three tests selected for further evaluation from the twenty-four test/material properties initially examined under the NCHRP 9-19 project. Currently, no standard triaxial testing conditions in terms of the magnitude of the deviator and confining stresses have been specified. In addition, a repeated haversine axial compressive load pulse of 0.1 second and a rest period of 0.9 second are commonly used as part of the triaxial testing conditions. The overall objective of this research was to define the loading conditions that created by a moving truck load in the hot mixed asphalt (HMA) layer. The loading conditions were defined in terms of the triaxial stress levels and the corresponding loading time. Dynamic mechanistic analysis with circular stress distribution was used to closely simulate field loading conditions. Extensive mechanistic analyses of three different asphalt pavement structures subjected to moving traffic loads at various speeds and under braking and non-braking conditions were conducted using the 3D-Move model. Prediction equations for estimating the anticipated deviator and confining stresses along with the equivalent deviator stress pulse duration as a function of pavement temperature, vehicle speed, and asphalt mixture's stiffness have been developed. The magnitude of deviator stress, sigmad and confining stress, sigmac, were determined by converting the stress tensor computed in the HMA layer at 2" below pavement surface under a moving 18-wheel truck using the octahedral normal and shear

  2. True Tri-axial testing of Castlegate Sandstone

    NASA Astrophysics Data System (ADS)

    Ingraham, M. D.; Issen, K.; Holcomb, D.

    2009-12-01

    Deformation bands in high porosity sandstone are an important geological feature for geologists and petroleum engineers; however, their formation is not fully understood. Axisymmetric compression, the common test for this material, is not sufficient to fully evaluate localization criteria. This study seeks to investigate the influence of the second principal stress on the failure and the formation of deformation bands in Castlegate sandstone. Experimental results from tests run in the axisymmetric compression stress state, as well as a stress state between axisymmetric compression and pure shear will be presented. Samples are tested using a custom triaxial testing rig at Sandia National Laboratories capable of applying stresses up to 400 MPa. Acoustic emissions are used to locate deformation bands should they not be visible on the specimen exterior. It is suspected that the second invariant of stress has a strong contribution to the failure mode and band formation. These results could have significant bearing on petroleum extraction as well as carbon dioxide sequestration.

  3. Internal stresses in Phobos and other triaxial bodies

    NASA Technical Reports Server (NTRS)

    Dobrovolskis, A. R.

    1982-01-01

    The unusual dynamical behavior of Phobos, its strange appearance, and its mysterious network of grooves all make it an intriguing object. Geophysical studies, though, have been hampered by the lack of suitable theories applicable to nonspherical bodies. In this paper the Martian satellites are modeled as homogeneous, elastic triaxial ellipsoids subject to tidal, rotational, and self-gravitational stresses. A novel semianalytical treatment then gives the stress and strain fields throughout their interiors. Yield phenomena and their possible surface expressions are also investigated. The results indicate that Phobos and Deimos have always been stable with respect to tidal fracture or disruption, but that Phobos will probably break up before colliding with Mars. Applications of the new formulation to other nonspherical bodies in the solar system are also discussed.

  4. {alpha}-clustering and triaxial deformations in {sup 40}Ca

    SciTech Connect

    Taniguchi, Yasutaka; Kimura, Masaaki; Kanada-En'yo, Yoshiko; Horiuchi, Hisashi

    2007-11-30

    We have studied the positive-parity states of {sup 40}Ca using antisymmetrized molecular dynamics (AMD) and the generator coordinate method (GCM). Imposing two different kinds of constraints on the variational calculation, we have found various kinds of {sup 40}Ca structures such as a deformed-shell structure, as well as {alpha}-{sup 36}Ar and {sup 12}C-{sup 28}Si cluster structures. After the GCM calculation, we obtained a normal-deformed band and a superdeformed band together with their side bands associated with triaxial deformation. The calculated B(E2) values agreed well with empirical data. It was also found that the normal-deformed and superdeformed bands contain {alpha}-{sup 36}Ar and {sup 12}C-{sup 28}Si cluster structure components, respectively. This leads to the presence of an {alpha}-{sup 36}Ar higher-nodal band occurring above the normal-deformed band.

  5. Clustering and triaxial deformations of {sup 40}Ca

    SciTech Connect

    Taniguchi, Yasutaka; Kimura, Masaaki; Kanada-En'yo, Yoshiko; Horiuchi, Hisashi

    2007-10-15

    We have studied the positive-parity states of {sup 40}Ca using antisymmetrized molecular dynamics (AMD) and the generator coordinate method (GCM). Imposing two different kinds of constraints on the variational calculation, we have found various kinds of {sup 40}Ca structures such as a deformed-shell structure, as well as {alpha}-{sup 36}Ar and {sup 12}C-{sup 28}Si cluster structures. After the GCM calculation, we obtained a normal-deformed band and a superdeformed band together with their side bands associated with triaxial deformation. The calculated B(E2) values agreed well with empirical data. It was also found that the normal-deformed and superdeformed bands have non-negligible {alpha}-{sup 36}Ar cluster and {sup 12}C-{sup 28}Si cluster components, respectively. This leads to the presence of an {alpha}-{sup 36}Ar higher nodal band occurring above the normal-deformed band.

  6. Energy expenditure estimation during normal ambulation using triaxial accelerometry and barometric pressure.

    PubMed

    Wang, Jingjing; Redmond, Stephen J; Voleno, Matteo; Narayanan, Michael R; Wang, Ning; Cerutti, Sergio; Lovell, Nigel H

    2012-11-01

    Energy expenditure (EE) is an important parameter in the assessment of physical activity. Most reliable techniques for EE estimation are too impractical for deployment in unsupervised free-living environments; those which do prove practical for unsupervised use often poorly estimate EE when the subject is working to change their altitude by walking up or down stairs or inclines. This study evaluates the augmentation of a standard triaxial accelerometry waist-worn wearable sensor with a barometric pressure sensor (as a surrogate measure for altitude) to improve EE estimates, particularly when the subject is ascending or descending stairs. Using a number of features extracted from the accelerometry and barometric pressure signals, a state space model is trained for EE estimation. An activity classification algorithm is also presented, and this activity classification output is also investigated as a model input parameter when estimating EE. This EE estimation model is compared against a similar model which solely utilizes accelerometry-derived features. A protocol (comprising lying, sitting, standing, walking, walking up stairs, walking down stairs and transitioning between activities) was performed by 13 healthy volunteers (8 males and 5 females; age: 23.8 ± 3.7 years; weight: 70.5 ± 14.9 kg), whose instantaneous oxygen uptake was measured by means of an indirect calorimetry system (K4b(2), COSMED, Italy). Activity classification improves from 81.65% to 90.91% when including barometric pressure information; when analyzing walking activities alone the accuracy increases from 70.23% to 98.54%. Using features derived from both accelerometry and barometry signals, combined with features relating to the activity classification in a state space model, resulted in a VO(2) estimation bias of -0.00 095 and precision (1.96SD) of 3.54 ml min(-1) kg(-1). Using only accelerometry features gives a relatively worse performance, with a bias of -0.09 and precision (1.96SD) of 5

  7. Chiral Bands in Odd-Odd Triaxially Deformed Nuclei

    NASA Astrophysics Data System (ADS)

    Starosta, K.

    2001-10-01

    In rotational bands built on high-j single-particle orbitals in odd-odd nuclei having triaxial shapes, the angular momenta of the valence proton, the valence neutron, and the collective rotation tend to align along the perpendicular axes of the triaxial core. This occurs when the Fermi level is low within the proton (neutron) subshell, but high within the neutron (proton) subshell resulting in their angular momenta oriented along the short and long axes, respectively. The core angular momentum is oriented along the intermediate axis because it has the largest moment of inertia according to the model of irrotational flow. These three mutually perpendicular vectors can be arranged to form two systems which differ by intrinsic chirality, a left- and a right-handed system; the two systems cannot be transformed into each other by rotation or space inversion, but are related by an operator, which involves time reversal. Chirality resulting from orthogonal coupling of angular momenta is unique to rotational bands in atomic nuclei since these are the only systems where a significant part of the total spin results from single-particle contributions. In relation to time reversal, chirality is a novel example of spontaneous symmetry breaking, on the same level as octupole deformation in relation to space inversion. The main experimental fingerprint of chirality in nuclear rotation is the doubling of states in rotational bands. Δ I=1 doublet-band structures with remarkably similar experimental characteristics, recently observed for N=75 and N=73 isotones in the A ~130 region, have been interpreted as chiral-band partners built on the πh_11/2νh_11/2 configuration. Additional transition rate information is being investigated both experimentally and theoretically. The description of the chiral partner bands based on the microscopic Tilted Axis Cranking approach in the intrinsic, body-fixed reference frame and phenomenological core-particle coupling in the laboratory reference

  8. Mechanical properties of gold twinned nanocubes under different triaxial tensile rates

    NASA Astrophysics Data System (ADS)

    Yang, Zailin; Zhang, Guowei; Luo, Gang; Sun, Xiaoqing; Zhao, Jianwei

    2016-08-01

    The gold twinned nanocubes under different triaxial tensile rates are explored by molecular dynamics simulation. Hydrostatic stress and Mises stress are defined in order to understand triaxial stresses. Twin boundaries prevent dislocations between twin boundaries from developing and dislocation angles are inconspicuous, which causes little difference between triaxial stresses. The mechanical properties of the nanocubes under low and high tensile rates are different. The curves of nanocubes under high tensile rates are more abrupt than those under low tensile rates. When the tensile rate is extremely big, the loadings are out of the nanocubes and there are not deformation and fracture in the internal nanocubes.

  9. User's Manual for Space Debris Surfaces (SD_SURF)

    NASA Technical Reports Server (NTRS)

    Elfer, N. C.

    1996-01-01

    A unique collection of computer codes, Space Debris Surfaces (SD_SURF), have been developed to assist in the design and analysis of space debris protection systems. SD_SURF calculates and summarizes a vehicle's vulnerability to space debris as a function of impact velocity and obliquity. An SD_SURF analysis will show which velocities and obliquities are the most probable to cause a penetration. This determination can help the analyst select a shield design which is best suited to the predominant penetration mechanism. The analysis also indicates the most suitable parameters for development or verification testing. The SD_SURF programs offer the option of either FORTRAN programs and Microsoft EXCEL spreadsheets and macros. The FORTRAN programs work with BUMPERII version 1.2a or 1.3 (Cosmic released). The EXCEL spreadsheets and macros can be used independently or with selected output from the SD_SURF FORTRAN programs.

  10. Chemical analyses of pore water from boreholes USW SD-6 and USW WT-24, Yucca Mountain, Nevada

    USGS Publications Warehouse

    Yang, I.C.; Peterman, Z.E.; Scofield, K.M.

    2003-01-01

    Analyses of pore water extracted from cores of boreholes USW SD-6 in the central part and USW WT-24 in the northern part of Yucca Mountain, Nevada, show significant vertical and lateral variations in dissolved-ion concentrations. Analyses of samples of only a few milliliters of pore water extracted by uniaxial or triaxial compression and by ultracentrifugation methods from adjacent core samples are generally in agreement, within the analytical error of 10% to 15%. However, the values of silica for water obtained by ultracentrifugation are consistently lower than values for water obtained by compression. The larger concentrations probably are due to localized pressure solution of silicate minerals during compression. The shallower water from core in borehole USW SD-6 was extracted from nonwelded units collectively referred to as the Paintbrush Tuff nonwelded (PTn). The deeper water was from core in both boreholes USW SD-6 and USW WT-24 in the nonwelded units referred to as the Calico Hills nonwelded (CHn). Significant differences in mean dissolved-ion concentrations in pore water between the PTn and CHn are (1) decreases in Ca, Mg, SO4, and NO3 and (2) increases in HCO3 and (Na+K)/(Ca+Mg) ratios. The decrease in NO3 and the increase in HCO3 could be the result of denitrification through the oxidation of organic matter. The decrease in Ca and associated increase in (Na+K)/(Ca+Mg) is the result of ion exchange with zeolites in the CHn in borehole USW WT-24. This effect is not nearly as pronounced in borehole USW SD-6, probably reflecting a smaller amount of zeolitization of the CHn in USW SD-6. Geochemical calculations using the PHREEQC code indicate that the pore water from both boreholes USW SD-6 and USW WT-24 is uniformly undersaturated in anhydrite, gypsum, and amorphous silica, but supersaturated in quartz and chalcedony. The saturation of calcite, aragonite, sepiolite, and dolomite is more variable from sample to sample. ?? 2002 Elsevier Science B.V. All rights

  11. Triaxial rotor in the SU(3) limit of the interacting boson model

    NASA Astrophysics Data System (ADS)

    Zhang, Yu; Pan, Feng; Dai, Lian-Rong; Draayer, J. P.

    2014-10-01

    A mapping from a triaxial rotor Hamiltonian to that of the SU(3) limit description in the interacting boson model (IBM) is established, which is achieved by the SU(3) realization of the triaxial rotor. A detailed comparison between the triaxial dynamics generated from the quadrupole-deformed rotor and those from the IBM image is made. The results indicate that the mapping can be well realized. A preliminary test for Ba128 further confirms the finite-N effect of the mapping. It thus provides an alternative way to understand the triaxiality in the finite-N system and additional insight into understanding the SU(3) IBM theory from microscopic point of view via the SU(3) shell model.

  12. Validation of uniaxial and triaxial accelerometers for the assessment of physical activity in preschool children

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Given the unique physical activity patterns of preschoolers, wearable electronic devices for quantitative assessment of physical activity require validation in this population. Study objective was to validate uniaxial and triaxial accelerometers in preschoolers. Room calorimetry was performed over 3...

  13. Shape trends and triaxiality in neutron-rich odd-mass Y and Nbisotopes

    SciTech Connect

    Luo, Y.X.; Rasmussen, J.O.; Gelberg, A.; Stefanescu, I.; Hamilton, J.H.; Ramayya, A.V.; Hwang, J.K.; Zhu, S.J.; Gore, P.M.; Fong,D.; Jones, E.F.; Wu, S.C.; Lee, I.Y.; Ginter, T.N.; Ma, W.C.; Ter-Akopian, G.M.; Daniel, A.V.; Stoyer, M.A.; Donangelo, R.

    2004-09-28

    New level schemes of Y and Nb isotopes are proposed based on measurements of prompt gamma rays from 252Cf fission at Gammasphere. Shape trends regarding triaxiality and quadrupole deformations are studied.

  14. Signatures of bulge triaxiality from kinematics in Baade's window

    NASA Technical Reports Server (NTRS)

    Zhao, Hongsheng; Spergel, David N.; Rich, R. Michael

    1994-01-01

    We study a sample of 62 Baade's Window, (l,b) = (1, -4)deg, K giants that have published proper motions, radial velocity, and metallicity. Using R(sub 0) = 8 kpc, we construct the velocity ellipsoids, namely the 3x3 velocity dispersion tensors, for the metal rich stars ((Fe/H) greater than or equal to 0) and metal poor stars ((Fe/H) less than or equal to -0.2). After diagonalizing the tensor, we find a vertex deviation characteristic of a nonaxisymmetric system. Eigenvalues for the two velocity ellipsoids (sigma(sub 1), sigma(sub 2), sigma(sub 3)) are (126, 89, 65) +/- 13 km/s for the metal rich sample and (154, 77, 83) +/- 25 km/s for the metal poor sample with their long axes pointing to two nearly perpendicular directions (l(sub v), b(sub v)) = (-65 +/- 9 deg, +14 +/- 9 deg) and (l(sub v), b(sub v)) = (25 +/- 14 deg, -11 +/- 14 deg), respectively. The vertex deviations of the velocity ellipsoids cannot be consistently explained by any oblate model. We are able to reject the hypothesis that the metal poor and metal rich populations are drawn from the same distribution at better than the 97% confidence level. We populate orbits in a realistic bar potential with a Gaussian velocity distribution, allowing us to simulate and interpret observations. We conclude that the data are consistent with a triaxial bulge pointing towards (l,b) with l less than 0 deg and b = 0 deg as suggested by earlier work on gas dynamics and the observed light distribution. We also predict that low latitude (absolute value of b less than or equal to 4 deg) bulge fields should show the vertex deviation more strongly and would therefore be the best locations for future proper motion studies. In the classification scheme of Athanassoula et al. (1983) the metal rich stars appear to occupy the B-family orbits which rotate in the prograde sense in the rest frame and have boxy shapes that are aligned with and supporting the bar. The metal poor stars in the sample lag behind the metal rich bulge and

  15. Signatures of bulge triaxiality from kinematics in Baade's window

    NASA Astrophysics Data System (ADS)

    Zhao, Hongsheng; Spergel, David N.; Rich, R. Michael

    1994-12-01

    We study a sample of 62 Baade's Window, (l,b) = (1, -4)deg, K giants that have published proper motions, radial velocity, and metallicity. Using R0 = 8 kpc, we construct the velocity ellipsoids, namely the 3x3 velocity dispersion tensors, for the metal rich stars ((Fe/H) greater than or equal to 0) and metal poor stars ((Fe/H) less than or equal to -0.2). After diagonalizing the tensor, we find a vertex deviation characteristic of a nonaxisymmetric system. Eigenvalues for the two velocity ellipsoids (sigma1, sigma2, sigma3) are (126, 89, 65) +/- 13 km/s for the metal rich sample and (154, 77, 83) +/- 25 km/s for the metal poor sample with their long axes pointing to two nearly perpendicular directions (lv, bv) = (-65 +/- 9 deg, +14 +/- 9 deg) and (lv, bv) = (25 +/- 14 deg, -11 +/- 14 deg), respectively. The vertex deviations of the velocity ellipsoids cannot be consistently explained by any oblate model. We are able to reject the hypothesis that the metal poor and metal rich populations are drawn from the same distribution at better than the 97% confidence level. We populate orbits in a realistic bar potential with a Gaussian velocity distribution, allowing us to simulate and interpret observations. We conclude that the data are consistent with a triaxial bulge pointing towards (l,b) with l less than 0 deg and b = 0 deg as suggested by earlier work on gas dynamics and the observed light distribution. We also predict that low latitude (absolute value of b less than or equal to 4 deg) bulge fields should show the vertex deviation more strongly and would therefore be the best locations for future proper motion studies. In the classification scheme of Athanassoula et al. (1983) the metal rich stars appear to occupy the B-family orbits which rotate in the prograde sense in the rest frame and have boxy shapes that are aligned with and supporting the bar. The metal poor stars in the sample lag behind the metal rich bulge and appear to occupy R-family orbits which rotate

  16. A triaxial accelerometer monkey algorithm for optimal sensor placement in structural health monitoring

    NASA Astrophysics Data System (ADS)

    Jia, Jingqing; Feng, Shuo; Liu, Wei

    2015-06-01

    Optimal sensor placement (OSP) technique is a vital part of the field of structural health monitoring (SHM). Triaxial accelerometers have been widely used in the SHM of large-scale structures in recent years. Triaxial accelerometers must be placed in such a way that all of the important dynamic information is obtained. At the same time, the sensor configuration must be optimal, so that the test resources are conserved. The recommended practice is to select proper degrees of freedom (DOF) based upon several criteria and the triaxial accelerometers are placed at the nodes corresponding to these DOFs. This results in non-optimal placement of many accelerometers. A ‘triaxial accelerometer monkey algorithm’ (TAMA) is presented in this paper to solve OSP problems of triaxial accelerometers. The EFI3 measurement theory is modified and involved in the objective function to make it more adaptable in the OSP technique of triaxial accelerometers. A method of calculating the threshold value based on probability theory is proposed to improve the healthy rate of monkeys in a troop generation process. Meanwhile, the processes of harmony ladder climb and scanning watch jump are proposed and given in detail. Finally, Xinghai NO.1 Bridge in Dalian is implemented to demonstrate the effectiveness of TAMA. The final results obtained by TAMA are compared with those of the original monkey algorithm and EFI3 measurement, which show that TAMA can improve computational efficiency and get a better sensor configuration.

  17. Experimental and analytical characterization of triaxially braided textile composites

    NASA Technical Reports Server (NTRS)

    Masters, John E.; Fedro, Mark J.; Ifju, Peter G.

    1993-01-01

    There were two components, experimental and analytical, to this investigation of triaxially braided textile composite materials. The experimental portion of the study centered on measuring the materials' longitudinal and transverse tensile moduli, Poisson's ratio, and strengths. The identification of the damage mechanisms exhibited by these materials was also a prime objective of the experimental investigation. The analytical portion of the investigation utilized the Textile Composites Analysis (TECA) model to predict modulus and strength. The analytical and experimental results were compared to assess the effectiveness of the analysis. The figures contained in this paper reflect the presentation made at the conference. They may be divided into four sections: a definition of the material system tested; followed by a series of figures summarizing the experimental results (these figures contain results of a Moire interferometry study of the strain distribution in the material, examples and descriptions of the types of damage encountered in these materials, and a summary of the measured properties); a description of the TECA model follows the experimental results (this includes a series of predicted results and a comparison with measured values); and finally, a brief summary completes the paper.

  18. Permeability Evolution of Granite Gneiss During Triaxial Creep Tests

    NASA Astrophysics Data System (ADS)

    Liu, L.; Xu, W. Y.; Wang, H. L.; Wang, W.; Wang, R. B.

    2016-09-01

    Permeability is an important factor for seepage analysis of rock material, and a key factor in ensuring the safety of underground works. In this study, the permeability evolution of granite gneiss during triaxial creep tests was investigated. In the context of an underground oil storage cavern in China, a series of hydro-mechanical coupling creep tests were conducted on rock cores of granite gneiss at three different pore pressures to reveal the effect of pore pressure on the permeability evolution and to investigate the correlation between the permeability and volumetric strain during the creep process. During the creep tests, the permeability decreases in the initial loading phase. At all deviatoric stress levels, the permeability remains stable in the steady creep stage and increases rapidly in the accelerated creep stage. Based on the test data, the initial permeability, steady permeability and peak permeability at various stress levels are defined. The effect of pore pressure on the permeability is captured by a linear model. In addition, the relationship between permeability and volumetric strain can be described as a process divided into three phases, with different functions in each phase.

  19. Falls event detection using triaxial accelerometry and barometric pressure measurement.

    PubMed

    Bianchi, Federico; Redmond, Stephen J; Narayanan, Michael R; Cerutti, Sergio; Celler, Branko G; Lovell, Nigel H

    2009-01-01

    A falls detection system, employing a Bluetooth-based wearable device, containing a triaxial accelerometer and a barometric pressure sensor, is described. The aim of this study is to evaluate the use of barometric pressure measurement, as a surrogate measure of altitude, to augment previously reported accelerometry-based falls detection algorithms. The accelerometry and barometric pressure signals obtained from the waist-mounted device are analyzed by a signal processing and classification algorithm to discriminate falls from activities of daily living. This falls detection algorithm has been compared to two existing algorithms which utilize accelerometry signals alone. A set of laboratory-based simulated falls, along with other tasks associated with activities of daily living (16 tests) were performed by 15 healthy volunteers (9 male and 6 female; age: 23.7 +/- 2.9 years; height: 1.74 +/- 0.11 m). The algorithm incorporating pressure information detected falls with the highest sensitivity (97.8%) and the highest specificity (96.7%).

  20. Micromechanics of Brittle Creep Under Triaxial Loading Conditions

    NASA Astrophysics Data System (ADS)

    Meredith, P. G.; Brantut, N.; Baud, P.; Heap, M. J.

    2011-12-01

    In the upper crust, the chemical influence of pore water promotes time-dependent brittle deformation through sub-critical crack growth. Sub-critical crack growth allows rocks to deform and fail (i) at stresses far below their short-term failure strength, and (ii) even at constant applied stress ("brittle creep"). Here we provide a micromechanical model and experimental results describing time-dependent brittle creep of water-saturated granite under triaxial stress conditions. Macroscopic brittle creep is modeled on the basis of microcrack extension under compressive stresses due to sub-critical crack growth. The incremental strains due to the growth of microcracks in compression are derived from the sliding wing-crack model of Ashby and Sammis (1990). Crack length evolution is computed from Charles' law. The macroscopic strain and strain rates are then computed from the change in energy potential due to microcrack growth. They are non-linear, and compare well with complementary experimental results obtained on granite samples. Primary creep (decelerating strain) corresponds to decreasing crack growth rate , due to an initial decrease in stress intensity factor with increasing crack length in compression. Tertiary creep (accelerating strain as failure is approached) corresponds to an increase in crack growth rate due to crack interactions. Secondary creep with apparently constant strain rate arises as merely an inflexion between the two end-member phases.

  1. Improving energy expenditure estimation by using a triaxial accelerometer.

    PubMed

    Chen, K Y; Sun, M

    1997-12-01

    In our study of 125 subjects (53 men and 72 women) for two 24-h periods, we validated energy expenditure (EE), estimated by a triaxial accelerometer (Tritrac-R3D), by using a whole-room indirect calorimeter under close-to-normal living conditions. The estimated EE was correlated with the measured total EE for the 2 days (r = 0. 925 and r = 0.855; P < 0.001) and in minute-by-minute EE (P < 0.01). Resting EE formulated by the Tritrac was found to be similar to the measured values [standard errors of estimation (SEE) = 0.112 W/kg; P = 0.822]. The Tritrac significantly underestimated total EE, EE for physical activities, EE of sedentary and light-intensity activities, and EE for exercise such as stepping (all P < 0.001). We developed a linear and a nonlinear model to predict EE by using the acceleration components from the Tritrac. Predicted EE was significantly improved with both models in estimating total EE, total EE for physical activities, EE in low-intensity activities, minute-by-minute averaged relative difference, and minute-by-minute SEE (all P < 0. 05). Furthermore, with our generalized models and by using subjects' physical characteristics and body acceleration, EE can be estimated with higher accuracy (averaged SEE = 0.418 W/kg) than with the Tritrac model.

  2. Identification of triaxial strongly deformed band in {sup 168}Hf.

    SciTech Connect

    Yadav, R. B.; Ma, W. C.; Hagemann, G. B.; Bengtsson, R.; Ryde, H.; Carpenter, M. P.; Janssens, R. V. F.; Khoo, T. L.; Kondev, F. G.; Lauritsen, T.; Lister, C. J.; Mississippi State Univ.; Niels Bohr Inst.; Lund Inst. of Tech.; Lund. Univ.; Univ. di Milano; Univ. of Bonn; U.S. Naval Academy; Univ. of Oslo; Univ. of Tennessee

    2008-01-01

    Possible decay pathways associated with three candidates for triaxial strongly deformed (TSD) bands in {sup 168}Hf have been investigated. The spin and excitation energy of the strongest band, TSD1, were determined approximately based on {gamma}-ray coincidence relationships. Discrete links were established for the second band. The overall agreement between the observed properties of the bands and cranking calculations using the ULTIMATE CRANKER code provides strong support for an interpretation where band TSD1 is associated with a TSD minimum, ({var_epsilon}{sub 2},{gamma}) {approx} (0.43,20{sup o}), involving the {pi}(i{sub 13/2}){sup 2} and the {nu}(j{sub 15/2}) high-j orbitals. This constitutes the first identification of a TSD band in Hf isotopes, which has been long-predicted by theoretical studies. The second band is understood as being associated with a near-prolate shape and a deformation enhanced with respect to the normal deformed bands. It is proposed to be built on the {pi}(i{sub 13/2}h{sub 9/2}) {nu}(i{sub 13/2}){sup 2} configuration.

  3. Substellar objects around the sdB eclipsing Binaries

    NASA Astrophysics Data System (ADS)

    Zhu, Liying; Qian, Shengbang; Liao, Wenping; Zhao, Ergang; Li, Linjia

    2016-07-01

    The sdB-type eclipsing binary consists a very hot subdwarf B (sdB) type primary and a low mass secondary with short period. They are detached binaries and show very narrow eclipse profiles, which benefits the determination of the precise eclipse times. With the precise times of light minimum, we can detected small mass objects around them by analyzing the observed-calculated (O-C) curve based on the light time effect. For searching the substellar objects orbiting around the binaries, we have monitored sdB-type eclipsing binaries for decades. A group of brown dwarfs and planets have been detected since then. In the present paper, we focus on the target NSVS07826147, which may be another exoplanet host candidate among the group of the sdB-type eclipsing binaries.

  4. Composite particle representation for light sd shell nuclei

    SciTech Connect

    Collinson, D.F.

    1986-01-01

    The Composite Particle Representation is applied to light sd shell nuclei /sup 20/O, /sup 20/F and /sup 20/Ne. The energy spectrum is found to agree exactly with the shell model in all cases. The CPR theory is then used to examine the possible boson structure of sd shell wavefunctions. Only in the case of /sup 20/O are the wavefunctions found to have a high boson probability.

  5. On the Components of Segregation Distortion in DROSOPHILA MELANOGASTER. III. Nature of Enhancer of Sd

    PubMed Central

    Brittnacher, John G.; Ganetzky, Barry

    1984-01-01

    Analysis of X-ray-induced deletions in the Segregation Distorter (SD) chromosome, SD-5, revealed that this chromosome had a gene proximal to lt in the centric heterochromatin of 2L that strongly enhanced the meiotic drive caused by the SD chromosome. This Enhancer of Segregation Distortion [E(SD)] locus had not been characterized in earlier studies of SD chromosomes because it cannot be readily separated by recombination from the Responder (Rsp) locus in the proximal heterochromatin of 2R.—To determine whether E(SD) is a general component of all SD chromosomes and to examine further its effects on distortion, we produced deletions of E(SD) in three additional SD chromosomes. Analysis of these deletions leads to the following conclusions: (1) along with Sd and Rsp, E(SD) is common to all SD chromosomes; (2) the E(SD) allele on each SD chromosome enhances distortion by the same amount, which indicates that allelic variation at the E(SD) locus is not responsible for the different drive strengths seen among SD chromosomes; (3) E(SD) causes very little or no distortion by itself in the absence of Sd; (4) E(SD), like Sd, acts in a dosage-dependent manner; (5) E(SD) exerts its effect in cis or trans to Sd; and (6) if E(SD)+ exists, its function is not related to SD. PMID:6428976

  6. Purification, Characterization, and Optimum Conditions of Fermencin SD11, a Bacteriocin Produced by Human Orally Lactobacillus fermentum SD11.

    PubMed

    Wannun, Phirawat; Piwat, Supatcharin; Teanpaisan, Rawee

    2016-06-01

    Fermencin SD11, a bacteriocin produced by human orally Lactobacillus fermentum SD11, was purified, characterized, and optimized in conditions for bacterial growth and bacteriocin production. Fermencin SD11 was purified using three steps of ammonium sulfate precipitation, gel filtration chromatography, and reverse-phase high-performance liquid chromatography. The molecular weight was found to be 33,000 Da using SDS-PAGE and confirmed as 33,593.4 Da by liquid chromatography-mass spectrometry. Fermencin SD11 exhibited activity against a wide range of oral pathogens including cariogenic and periodontogenic pathogens and Candida. The active activity was stable between 60 - 80 °C in a pH range of 3.0 to 7.0. It was sensitive to proteolytic enzymes (proteinase K and trypsin), but it was not affected by α-amylase, catalase, lysozyme, and saliva. The optimum conditions for growth and bacteriocin production of L. fermentum SD11 were cultured at acidic with pH of 5.0-6.0 at 37 or 40 °C under aerobic or anaerobic conditions for 12 h. It is promising that L. fermentum SD11 and its bacteriocin may be an alternative approach for promoting oral health or prevention of oral diseases, e.g., dental caries and periodontitis, which would require further clinical trials. PMID:26892008

  7. Experimental investigation on mechanical damage characteristics of sandstone under triaxial cyclic loading

    NASA Astrophysics Data System (ADS)

    Yang, Sheng-Qi; Ranjith, P. G.; Huang, Yan-Hua; Yin, Peng-Fei; Jing, Hong-Wen; Gui, Yi-Lin; Yu, Qing-Lei

    2015-05-01

    The mechanical damage characteristics of sandstone subjected to cyclic loading is very significant to evaluate the stability and safety of deep excavation damage zones. However to date, there are very few triaxial experimental studies of sandstone under cyclic loading. Moreover, few X-ray micro-computed tomography (micro-CT) observations have been adopted to reveal the damage mechanism of sandstone under triaxial cyclic loading. Therefore, in this research, a series of triaxial cyclic loading tests and X-ray micro-CT observations were conducted to analyse the mechanical damage characteristics of sandstone with respect to different confining pressures. The results indicated that at lower confining pressures, the triaxial strength of sandstone specimens under cyclic loading is higher than that under monotonic loading; whereas at confining pressures above 20 MPa, the triaxial strength of sandstone under cyclic loading is approximately equal to that under monotonic loading. With the increase of cycle number, the crack damage threshold of sandstone first increases, and then significantly decreases and finally remains constant. Based on the damage evolution of irreversible deformation, it appears that the axial damage value of sandstone is all higher than the radial damage value before the peak strength; whereas the radial damage value is higher than the axial damage value after the peak strength. The evolution of Young's modulus and Poisson's ratio of sandstone can be characterized as having four stages: (i) Stage I: material strengthening; (ii) Stage II: material degradation; (iii) Stage III: material failure and (iv) Stage IV: structure slippage. X-ray micro-CT observations demonstrated that the CT scanning surface images of sandstone specimens are consistent with actual surface crack photographs. The analysis of the cross-sections of sandstone supports that the system of crack planes under triaxial cyclic loading is much more complicated than that under triaxial

  8. Tidal spin down rates of homogeneous triaxial viscoelastic bodies

    NASA Astrophysics Data System (ADS)

    Quillen, Alice C.; Kueter-Young, Andrea; Frouard, Julien; Ragozzine, Darin

    2016-08-01

    We use numerical simulations to measure the sensitivity of the tidal spin down rate of a homogeneous triaxial ellipsoid to its axis ratios by comparing the drift rate in orbital semi-major axis to that of a spherical body with the same mass, volume and simulated rheology. We use a mass-spring model approximating a viscoelastic body spinning around its shortest body axis, with spin aligned with orbital spin axis, and in circular orbit about a point mass. The torque or drift rate can be estimated from that predicted for a sphere with equivalent volume if multiplied by 0.5 (1 + b^4/a^4)(b/a)^{-4/3} (c/a)^{-α _c} where b/a and c/a are the body axis ratios and index αc ≈ 1.05 is consistent with the random lattice mass spring model simulations but αc = 4/3 suggested by scaling estimates. A homogeneous body with axis ratios 0.5 and and 0.8, like Haumea, has orbital semi-major axis drift rate about twice as fast as a spherical body with the same mass, volume and material properties. A simulation approximating a mostly rocky body but with 20% of its mass as ice concentrated at its ends has a drift rate 10 times faster than the equivalent homogeneous rocky sphere. However, this increase in drift rate is not enough to allow Haumea's satellite, Hi'iaka, to have tidally drifted away from Haumea to its current orbital semi-major axis.

  9. Behavior of an MBT waste in monotonic triaxial shear tests

    SciTech Connect

    Bhandari, Athma Ram Powrie, William

    2013-04-15

    Highlights: ► We studied the stress–strain–strength characteristics of an MBT waste. ► Rate of mobilization of strength with strain depends on initial density. ► Image analysis technique was used to determine whole-specimen displacement fields. ► Initial mode of deformation of a loose specimen is one-dimensional compression. ► Reinforcing elements enhance the resistance to lateral and volumetric deformation. - Abstract: Legislation in some parts of the world now requires municipal solid waste (MSW) to be processed prior to landfilling to reduce its biodegradability and hence its polluting potential through leachate and fugitive emission of greenhouse gases. This pre-processing may be achieved through what is generically termed mechanical–biological-treatment (MBT). One of the major concerns relating to MBT wastes is that the strength of the material may be less than for raw MSW, owing to the removal of sheet, stick and string-like reinforcing elements during processing. Also, the gradual increase in mobilized strength over strains of 30% or so commonly associated with unprocessed municipal solid waste may not occur with treated wastes. This paper describes a series of triaxial tests carried out to investigate the stress–strain–strength characteristics of an MBT waste, using a novel digital image analysis technique for the determination of detailed displacement fields over the whole specimen. New insights gained into the mechanical behavior of MBT waste include the effect of density on the stress–strain response, the initial 1-D compression of lightly consolidated specimens, and the likely reinforcing effect of small sheet like particles remaining in the waste.

  10. Energy expenditure estimation using triaxial accelerometry and barometric pressure measurement.

    PubMed

    Voleno, Matteo; Redmond, Stephen J; Cerutti, Sergio; Lovell, Nigel H

    2010-01-01

    Energy expenditure (EE) is a parameter of great relevance in studies involving the assessment of physical activity. However, most reliable techniques for EE estimation are impractical for use in free-living environments, and those which are practically useful often poorly track EE when the subject is working to change their altitude, for example when ascending or descending stairs or slopes. The aim of this study is to evaluate the utility of adding barometric pressure related features, as a surrogate measure for altitude, to existing accelerometry related features to estimate the subject's EE. The EE estimation system described is based on a triaxial accelerometer (triax) and a barometric pressure sensor. The device is wireless, with Bluetooth connectivity for data retrieval, and is mounted at the subject's waist. Using a number of features extracted from the triax and barometric pressure signals, a linear model is trained for EE estimation. This EE estimation model is compared to its counterpart, which solely utilizes accelerometry signals. A protocol (comprising lying, sitting, standing, walking phases) was performed by 13 healthy volunteers (8 male and 5 female; age: 23.8 ± 3.7 years; weight: 70.5 ± 14.9 kg), whose instantaneous oxygen uptake was measured by means of an indirect calorimetry system. The model incorporating barometric pressure information estimated the oxygen uptake with the lowest mean square error of 4.5 ± 1.7 (mlO(2).min(-1).kg(-1))(2), in comparison to 7.1 ± 2.3 (mlO(2).min(-1).kg(-1))(2) using only accelerometry-based features.

  11. SD-CAS: Spin Dynamics by Computer Algebra System.

    PubMed

    Filip, Xenia; Filip, Claudiu

    2010-11-01

    A computer algebra tool for describing the Liouville-space quantum evolution of nuclear 1/2-spins is introduced and implemented within a computational framework named Spin Dynamics by Computer Algebra System (SD-CAS). A distinctive feature compared with numerical and previous computer algebra approaches to solving spin dynamics problems results from the fact that no matrix representation for spin operators is used in SD-CAS, which determines a full symbolic character to the performed computations. Spin correlations are stored in SD-CAS as four-entry nested lists of which size increases linearly with the number of spins into the system and are easily mapped into analytical expressions in terms of spin operator products. For the so defined SD-CAS spin correlations a set of specialized functions and procedures is introduced that are essential for implementing basic spin algebra operations, such as the spin operator products, commutators, and scalar products. They provide results in an abstract algebraic form: specific procedures to quantitatively evaluate such symbolic expressions with respect to the involved spin interaction parameters and experimental conditions are also discussed. Although the main focus in the present work is on laying the foundation for spin dynamics symbolic computation in NMR based on a non-matrix formalism, practical aspects are also considered throughout the theoretical development process. In particular, specific SD-CAS routines have been implemented using the YACAS computer algebra package (http://yacas.sourceforge.net), and their functionality was demonstrated on a few illustrative examples.

  12. SD-CAS: Spin Dynamics by Computer Algebra System

    NASA Astrophysics Data System (ADS)

    Filip, Xenia; Filip, Claudiu

    2010-11-01

    A computer algebra tool for describing the Liouville-space quantum evolution of nuclear 1/2-spins is introduced and implemented within a computational framework named Spin Dynamics by Computer Algebra System (SD-CAS). A distinctive feature compared with numerical and previous computer algebra approaches to solving spin dynamics problems results from the fact that no matrix representation for spin operators is used in SD-CAS, which determines a full symbolic character to the performed computations. Spin correlations are stored in SD-CAS as four-entry nested lists of which size increases linearly with the number of spins into the system and are easily mapped into analytical expressions in terms of spin operator products. For the so defined SD-CAS spin correlations a set of specialized functions and procedures is introduced that are essential for implementing basic spin algebra operations, such as the spin operator products, commutators, and scalar products. They provide results in an abstract algebraic form: specific procedures to quantitatively evaluate such symbolic expressions with respect to the involved spin interaction parameters and experimental conditions are also discussed. Although the main focus in the present work is on laying the foundation for spin dynamics symbolic computation in NMR based on a non-matrix formalism, practical aspects are also considered throughout the theoretical development process. In particular, specific SD-CAS routines have been implemented using the YACAS computer algebra package (http://yacas.sourceforge.net), and their functionality was demonstrated on a few illustrative examples.

  13. Decay out of SD Band in ^192Pb

    NASA Astrophysics Data System (ADS)

    McNabb, D. P.; Cizewski, J. A.; Ding, K. Y.; Fotiades, N.; Archer, D. E.; Becker, J. A.; Bernstein, L. A.; Hauschild, K.; Younes, W.; Clark, R. M.; Fallon, P.; Lee, I. Y.; Macchiavelli, A. O.; MacLeod, R. W.

    1997-04-01

    Gamma-ray transitions linking the yrast SD bands to the known (ND) levels have been found in ^194Pb(M. J. Brinkman, et al., Phys. Rev. C53), R1461 (1996), A. Lopez-Martens, et al., Phys. Lett. B380, 18 (1996) and K. Hauschild, et al., submitted to Phys. Rev. C (1996). and ^194Hg.(T. L. Khoo, et al., Phys. Rev. Lett. 76), 1583 (1996). The spin, parity and excitation energy of these SD bands were established. Linking transitions are understood as arising from ND states nearby in excitation energy which are admixed with the SD states.(E. Vigezzi, et al., Phys. Lett. B249), 163 (1990). We anticipate a smaller phase space for quasicontinuous decay of the SD band in ^192Pb because it is predicted to lie lower in excitation than the SD band in ^194Pb.footnote S. J. Krieger, et al. Nucl. Phys. A542, 43 (1992). To search for linking transitions in ^192Pb we used the Gammasphere array at LBNL and the ^24Mg(^173Yb,5n) reaction at 134 MeV. Candidates for linking transitions and general features of the decay will be discussed.

  14. Triaxial electrospun nanofiber membranes for controlled dual release of functional molecules.

    PubMed

    Han, Daewoo; Steckl, Andrew J

    2013-08-28

    A novel dual drug delivery system is presented using triaxial structured nanofibers, which provides different release profiles for model drugs separately loaded in either the sheath or the core of the fiber. Homogenous, coaxial and triaxial fibers containing a combination of materials (PCL, polycaprolactone; PVP, polyvinylpyrrolidone) were fabricated. The drug release profiles were simulated using two color dyes (KAB, keyacid blue; KAU, keyacid uranine), whose release in physiological solution was measured using optical absorption as a function of time. To reach the level of 80% release of encapsulated dye from core, triaxial fibers with a PCL intermediate layer exhibited a ~24× slower release than that from coaxial fibers. At the same time, the hygroscopic sheath layer of the triaxial fibers provided an initial burst release (~ 80% within an hour) of a second dye as high as that from conventional single and coaxial fibers. The triaxial fiber membrane provides both a quick release from the outer sheath layer for short-term treatment and a sustained release from the fiber core for long-term treatment. The intermediate layer between inner core and outer sheath acts as a barrier to prevent leaching from the core, which can be especially important when the membranes are used in wet application. The formation of tri/multiaxially electrospun nanofibrous membranes will be greatly beneficial for biomedical applications by enabling different release profiles of two different drugs from a membrane.

  15. Hydromechanical behavior of heterogeneous carbonate rock under proportional triaxial loadings

    NASA Astrophysics Data System (ADS)

    Dautriat, JéRéMie; Gland, Nicolas; Dimanov, Alexandre; Raphanel, Jean

    2011-01-01

    The influence of stress paths representative of reservoir conditions on the poromechanical behavior and coupled directional permeabilities evolution of a heterogeneous carbonate has been studied. Our experimental methodology is based on performing confined compression tests keeping constant a stress path coefficient K = Δσr/Δσa ratio of the radial and axial stress magnitudes, commonly assumed to be representative of reservoir stress state evolution during production. The experiments are performed in a triaxial cell specially designed to measure the permeability in two orthogonal directions, along and transverse to the direction of maximum stress. The tested rock is a heterogeneous bioclastic carbonate, the Estaillades limestone, with a bimodal porosity, of mean value around 28% and a moderate permeability of mean value 125 mdarcy. Microstructural analyses of initial and deformed samples have been performed combining X-ray tomography and microtomography, scanning electron microscopy (SEM) observations, and mercury injection porosimetry. The microstructural heterogeneity, observable by SEM, is characterized by the arrangement of the micrograins of calcite in either dense or microporous aggregates surrounded by larger pores. The spatial distribution of the two kinds of aggregates is responsible for important density fluctuations throughout the samples, recorded by X-ray tomography, which characterizes the mesoheterogeneity. We show that this mesoheterogeneity is a source of a large directional variability of permeability for a given specimen and also from sample to sample. In addition, the fluctuation of the porosity in the tested set of samples, from 24% to 31%, is an expression of the macroheterogeneity. Macroscopic mechanical data and the stress path dependency of porosity and permeability have been measured in the elastic, brittle, and compaction regimes. No significant effect of the stress path on the evolution of directional permeabilities is observed in the

  16. Phase diagram for a cubic-Q interacting boson model Hamiltonian: Signs of triaxiality

    SciTech Connect

    Fortunato, L.; Alonso, C. E.; Arias, J. M.; Garcia-Ramos, J. E.; Vitturi, A.

    2011-07-15

    An extension of the Interacting Boson Model that includes the cubic (QxQxQ){sup (0)} term is proposed. The potential energy surface for the cubic quadrupole interaction is explicitly calculated within the coherent state formalism using the complete ({chi}-dependent) expression for the quadrupole operator. The Q-cubic term is found to depend on the asymmetry deformation parameter {gamma} as a linear combination of cos(3{gamma}) and cos{sup 2}(3{gamma}) terms, thereby allowing for triaxiality. The phase diagram of the model in the large N limit is explored: The orders of the phase transition surfaces that define the phase diagram are described, and the possible nuclear equilibrium shapes are established. It is found that for this particular Hamiltonian, contrary to expectations, there is only a very tiny region of triaxiality, and that the transition from prolate to oblate shapes is so fast that, in most cases, the onset of triaxiality might go unnoticed.

  17. Increased rigidly triaxial deformations in neutron-rich Mo, Ru isotopes

    NASA Astrophysics Data System (ADS)

    Liang, WuYang; Jiao, ChangFeng; Xu, FuRong; Fu, XiMing

    2016-09-01

    Pairing-deformation-frequency self-consistent crankingWoods-Saxon model is employed to investigate the triaxiality in the ground states of the neutron-rich even-even Mo, Ru isotopes. Deformation evolutions and transition probabilities have been studied, giving the triaxial shapes in their ground states. The kinematic moments of inertia have been calculated to illustrate the gradually rigid deformation. To understand the origin of the asymmetry shape in this region, we analyze the evolution of single-particle orbits with changing γ deformation. The present calculations reveal the importance of the triaxial deformation in describing not only static property, but also rotational behaviors in this mass region, providing significant probes into the shell structure around.

  18. Scalar Damage Variable Determined in the Uniaxial and Triaxial Compression Conditions of Sandstone Samples

    NASA Astrophysics Data System (ADS)

    Cieślik, Jerzy

    2013-03-01

    The article is based on the results of uniaxial and triaxial compression tests, performed on Wustenzeller sandstone. An overview of the possible definitions of damage variable describing the process of damage development on the basis of various hypotheses has been presented in the first part of the article. In the main part of the article the author has presented the results of laboratory investigations, where the state of damage and its changes in rock samples under uniaxial and triaxial compression conditions were being observed. Using a modified procedure of triaxial tests, a definition of damage variable, determined on the basis of changes of volumetric stiffness of an examined rock, has been developed. Damage variable defined this way, in relation to a variable determined on the basis of axial stiffness changes, points to some anisotropy effects of damage phenomenon. The results obtained from both methods have been compared whereas the relations determining the evolution of damage variable in the loading process have been established.

  19. Validation of triaxial accelerometers to measure the lying behaviour of adult domestic horses.

    PubMed

    DuBois, C; Zakrajsek, E; Haley, D B; Merkies, K

    2015-01-01

    Examining the characteristics of an animal's lying behaviour, such as frequency and duration of lying bouts, has become increasingly relevant for animal welfare research. Triaxial accelerometers have the advantage of being able to continuously monitor an animal's standing and lying behaviour without relying on live observations or video recordings. Multiple models of accelerometers have been validated for use in monitoring dairy cattle; however, no units have been validated for use in equines. This study tested Onset Pendant G data loggers attached to the hind limb of each of two mature Standardbred horses for a period of 5 days. Data loggers were set to record their position every 20 s. Horses were monitored via live observations during the day and by video recordings during the night to compare activity against accelerometer data. All lying events occurred overnight (three to five lying bouts per horse per night). Data collected from the loggers was converted and edited using a macro program to calculate the number of bouts and the length of time each animal spent lying down by hour and by day. A paired t-test showed no significant difference between the video observations and the output from the data loggers (P=0.301). The data loggers did not distinguish standing hipshot from standing square. Predictability, sensitivity, and specificity were all >99%. This study has validated the use of Onset Pendant G data loggers to determine the frequency and duration of standing and lying bouts in adult horses when set to sample and register readings at 20 s intervals.

  20. Validation of triaxial accelerometers to measure the lying behaviour of adult domestic horses.

    PubMed

    DuBois, C; Zakrajsek, E; Haley, D B; Merkies, K

    2015-01-01

    Examining the characteristics of an animal's lying behaviour, such as frequency and duration of lying bouts, has become increasingly relevant for animal welfare research. Triaxial accelerometers have the advantage of being able to continuously monitor an animal's standing and lying behaviour without relying on live observations or video recordings. Multiple models of accelerometers have been validated for use in monitoring dairy cattle; however, no units have been validated for use in equines. This study tested Onset Pendant G data loggers attached to the hind limb of each of two mature Standardbred horses for a period of 5 days. Data loggers were set to record their position every 20 s. Horses were monitored via live observations during the day and by video recordings during the night to compare activity against accelerometer data. All lying events occurred overnight (three to five lying bouts per horse per night). Data collected from the loggers was converted and edited using a macro program to calculate the number of bouts and the length of time each animal spent lying down by hour and by day. A paired t-test showed no significant difference between the video observations and the output from the data loggers (P=0.301). The data loggers did not distinguish standing hipshot from standing square. Predictability, sensitivity, and specificity were all >99%. This study has validated the use of Onset Pendant G data loggers to determine the frequency and duration of standing and lying bouts in adult horses when set to sample and register readings at 20 s intervals. PMID:25273864

  1. 78 FR 48764 - South Dakota Disaster # SD-00061

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-09

    ... From the Federal Register Online via the Government Publishing Office SMALL BUSINESS ADMINISTRATION South Dakota Disaster SD-00061 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY...: Submit completed loan applications to: U.S. Small Business Administration, Processing and...

  2. 78 FR 41837 - Establishment of Class E Airspace; Parkston, SD

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-12

    ..., 40113, 40120; E.O. 10854, 24 FR 9565, 3 CFR, 1959-1963 Comp., p. 389. Sec. 71.1 0 2. The incorporation... the Parkston, SD, area, creating controlled airspace at Parkston Municipal Airport (78 FR 25232... ``significant rule'' under DOT Regulatory Policies and Procedures (44 FR 11034; February 26, 1979); and (3)...

  3. 75 FR 4417 - Wind Cave National Park, Custer County, SD

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-27

    ... Wind Cave National Park, Custer County, SD AGENCY: National Park Service. ACTION: Notice of... Statement, Wind Cave National Park, Custer County, South Dakota. SUMMARY: Pursuant to Section 102(2)(C) of... Environmental Impact Statement (Plan), Wind Cave National Park, Custer County, South Dakota. On December 3,...

  4. 76 FR 35935 - South Dakota Disaster Number SD-00041

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-20

    ... From the Federal Register Online via the Government Publishing Office U.S. SMALL BUSINESS ADMINISTRATION South Dakota Disaster Number SD-00041 AGENCY: U.S. Small Business Administration. ACTION... completed loan applications to: U.S. Small Business Administration, Processing and Disbursement...

  5. 76 FR 35936 - South Dakota Disaster Number SD-00041

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-20

    ... From the Federal Register Online via the Government Publishing Office U.S. SMALL BUSINESS ADMINISTRATION South Dakota Disaster Number SD-00041 AGENCY: U.S. Small Business Administration. ACTION... completed loan applications to: U.S. Small Business Administration, Processing and Disbursement...

  6. ICHPER-SD Asia Youth Health Related Physical Fitness Test.

    ERIC Educational Resources Information Center

    Journal of the International Council for Health, Physical Education, Recreation, Sport, and Dance, 1994

    1994-01-01

    Presents necessary information for administering the ICHPER-SD Asia Youth Health Related Physical Fitness Test, including descriptions of and scoring for each test item, needed equipment, notes, and suggested preparations for test leaders. The test includes the endurance run, situps in 60 seconds, pullups, sit and reach test, and skinfold…

  7. Insulin resistance in SD rats chronically treated with ethanol

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We have previously demonstrated that hepatic insulin signaling is disrupted in Sprague-Dawley (SD) rats fed EtOH-containing diets by total enteral nutrition (TEN). To determine if whole body insulin resistance could be demonstrated in the TEN model, we conducted euglycemic-hyperinsulinemic clamp st...

  8. 78 FR 39820 - Standing Rock Sioux Tribe Disaster #SD-00058

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-02

    ... ADMINISTRATION Standing Rock Sioux Tribe Disaster SD-00058 AGENCY: U.S. Small Business Administration. ACTION... Assistance Only for the Standing Rock Indian Reservation (FEMA-4123-DR), dated 06/25/2013. Incident: Severe... adversely affected by the disaster: Primary Area: Standing Rock Indian Reservation. The Interest Rates...

  9. True Triaxial Strength and Failure Modes of Cubic Rock Specimens with Unloading the Minor Principal Stress

    NASA Astrophysics Data System (ADS)

    Li, Xibing; Du, Kun; Li, Diyuan

    2015-11-01

    True triaxial tests have been carried out on granite, sandstone and cement mortar using cubic specimens with the process of unloading the minor principal stress. The strengths and failure modes of the three rock materials are studied in the processes of unloading σ 3 and loading σ 1 by the newly developed true triaxial test system under different σ 2, aiming to study the mechanical responses of the rock in underground excavation at depth. It shows that the rock strength increases with the raising of the intermediate principal stress σ 2 when σ 3 is unloaded to zero. The true triaxial strength criterion by the power-law relationship can be used to fit the testing data. The "best-fitting" material parameters A and n ( A > 1.4 and n < 1.0) are almost located in the same range as expected by Al-Ajmi and Zimmerman (Int J Rock Mech Min Sci 563 42(3):431-439, 2005). It indicates that the end effect caused by the height-to-width ratio of the cubic specimens will not significantly affect the testing results under true triaxial tests. Both the strength and failure modes of cubic rock specimens under true triaxial unloading condition are affected by the intermediate principal stress. When σ 2 increases to a critical value for the strong and hard rocks (R4, R5 and R6), the rock failure mode may change from shear to slabbing. However, for medium strong and weak rocks (R3 and R2), even with a relatively high intermediate principal stress, they tend to fail in shear after a large amount of plastic deformation. The maximum extension strain criterion Stacey (Int J Rock Mech Min Sci Geomech Abstr 651 18(6):469-474, 1981) can be used to explain the change of failure mode from shear to slabbing for strong and hard rocks under true triaxial unloading test condition.

  10. Why are the interband transitions among triaxially strongly deformed bands suppressed in even nuclei?

    SciTech Connect

    Sugawara-Tanabe, Kazuko; Tanabe, Kosai

    2011-05-06

    As top-on-top model has made a great success in explaining triaxially strongly deformed (TSD) bands in odd-A nuclei, we extend this model to even-A nuclei, i.e. two particles in different single-particle orbitals outside the triaxial rotor. In the lowest order approximation, the electromagnetic transitions between TSD bands in even-A case are reduced by a factor of 0.04 compared with odd-A case. It is one of the reasons why TSD bands are not yet explicitly observed in even-A nuclei.

  11. Automated segmentation of serous pigment epithelium detachment in SD-OCT images

    NASA Astrophysics Data System (ADS)

    Sun, Zhuli; Shi, Fei; Xiang, Dehui; Chen, Haoyu; Chen, Xinjian

    2015-03-01

    Pigment epithelium detachment (PED) is an important clinical manifestation of multiple chorio-retinal disease processes, which can cause the loss of central vision. A 3-D method is proposed to automatically segment serous PED in SD-OCT images. The proposed method consists of five steps: first, a curvature anisotropic diffusion filter is applied to remove speckle noise. Second, the graph search method is applied for abnormal retinal layer segmentation associated with retinal pigment epithelium (RPE) deformation. During this process, Bruch's membrane, which doesn't show in the SD-OCT images, is estimated with the convex hull algorithm. Third, the foreground and background seeds are automatically obtained from retinal layer segmentation result. Fourth, the serous PED is segmented based on the graph cut method. Finally, a post-processing step is applied to remove false positive regions based on mathematical morphology. The proposed method was tested on 20 SD-OCT volumes from 20 patients diagnosed with serous PED. The average true positive volume fraction (TPVF), false positive volume fraction (FPVF), dice similarity coefficient (DSC) and positive predictive value (PPV) are 97.19%, 0.03%, 96.34% and 95.59%, respectively. Linear regression analysis shows a strong correlation (r = 0.975) comparing the segmented PED volumes with the ground truth labeled by an ophthalmology expert. The proposed method can provide clinicians with accurate quantitative information, including shape, size and position of the PED regions, which can assist diagnose and treatment.

  12. Carbon abundances of sdO stars from SPY

    NASA Astrophysics Data System (ADS)

    Hirsch, Heiko; Heber, Uli

    2009-06-01

    Ströer et al. (2007) recently suggested a classification of sdOs according to supersolar and subsolar helium abundances, with only the helium-enriched stars showing signes of carbon and/or nitrogen in their optical spectra. We aim to derive reliable carbon and nitrogen abundances by fitting synthetic spectra to data obtained with the UVES spectrograph at ESO. Here we present our first results of the analysis of carbon abundances in hot subdwarf O stars. By constructing a grid of model atmospheres consisting of hydrogen, helium and carbon we were able to derive atmospheric parameters of nine carbon rich sdOs. We find log(NC/Ntotal) up to ten times higher than the solar value, while the mean value for the effective temperature and the surface gravity is slightly lower than derived by helium-hydrogen models only. Surprisingly, we also find three fast rotators among our program stars.

  13. Gray-shading for the SD-4060 graphics device

    NASA Technical Reports Server (NTRS)

    Gloeckler, C.

    1975-01-01

    Grays, a FORTRAN program, is described which will generate gray shading for the SD-4060 graphics device. The program produces 10 shades of gray ranging from no shading at all to complete coverage of the film frame. The graphing capabilities are summarized and illustrated. The figures displayed are representative of the microfilm output, but the distinction between various intensities is much clearer on the film, especially at the more intense shading.

  14. Shell Model Depiction of Isospin Mixing in sd Shell

    SciTech Connect

    Lam, Yi Hua; Smirnova, Nadya A.; Caurier, Etienne

    2011-11-30

    We constructed a new empirical isospin-symmetry breaking (ISB) Hamiltonian in the sd(1s{sub 1/2}, 0d{sub 5/2} and 0d{sub 3/2}) shell-model space. In this contribution, we present its application to two important case studies: (i){beta}-delayed proton emission from {sup 22}Al and (ii) isospin-mixing correction to superallowed 0{sup +}{yields}0{sup +}{beta}-decay ft-values.

  15. A highly triaxial N-body system tumbling about is intermediate axis

    NASA Technical Reports Server (NTRS)

    Duncan, Martin J.; Levison, Harold F.

    1989-01-01

    The results are presented of an N-body simulation which shows that it is possible for a highly triaxial self-gravitating system in dynamical equilibrium to exhibit stable figure rotation about its intermediate axis. The system is long-lived, lasting at least 20 half-mass crossing times of the final system. The nature of the simulation is summarized.

  16. Destructive interference of E2 matrix elements in a triaxial rotor model

    NASA Astrophysics Data System (ADS)

    Allmond, J. M.; Wood, J. L.; Kulp, W. D.

    2010-05-01

    A triaxial rotor model with independent inertia and electric quadrupole tensors is applied to nuclei that have certain E2 matrix elements equal to zero. It is shown that such vanishing E2 matrix elements are explained by the model as a destructive interference effect. The example of Pt196 is considered.

  17. Destructive interference of E2 matrix elements in a triaxial rotor model

    SciTech Connect

    Allmond, James M; Wood, J. L.; Kulp, W. D.

    2010-01-01

    A triaxial rotor model with independent inertia and electric quadrupole tensors is applied to nuclei that have certain E2 matrix elements equal to zero. It is shown that such vanishing E2 matrix elements are explained by the model as a destructive interference effect. The example of 196Pt is considered.

  18. Simulation of a true-triaxial deformation test on anisotropic gneiss using FLAC3D

    NASA Astrophysics Data System (ADS)

    Ye, Shenghua; Sehizadeh, Mehdi; Nasseri, Mohammad; Young, Paul

    2016-04-01

    A series of true-triaxial experiments have been carried out at the University of Toronto's Rock Fracture Dynamics Laboratory. Isotropic pegmatite and gneiss have been used to systematically study the effect of anisotropy on the strength, behaviour and seismic response. Samples were loaded under true-triaxial stress conditions and subjected to complex loading and unloading histories associated with rock deformation around underground openings. The results show expected patterns of weakness from preferentially oriented samples and highlight the importance of unloading history under true-triaxial conditions on the deformation and seismic response of the samples. These tests have been used to validate a synthetic simulation using the Itasca FLAC3D numerical code. The paper describes the FLAC3D simulations of the complex true-triaxial loading and unloading history of the different anisotropic samples. Various parameters were created to describe the physico-mechanical properties of the synthetic rock samples. Foliation planes of preferential orientations with respect to the primary loading direction were added to the synthetic rock samples to reflect the anisotropy of the gneiss. These synthetic rock samples were subjected to the same loading and unloading paths as the real rock samples, and failed in the same mechanism as what was observed from the experiments, and thus it proved the validity of this numerical simulation with FLAC3D.

  19. Simplifying touch data from tri-axial sensors using a new data visualization tool.

    PubMed

    Salud, Lawrence H; Kwan, Calvin; Pugh, Carla M

    2013-01-01

    Quantification and evaluation of palpation is a growing field of research in medicine and engineering. A newly developed tri-axial touch sensor has been designed to capture a multi-dimensional profile of touch-loaded forces. We have developed a data visualization tool as a first step in simplifying interpretation of touch for assessing hands-on clinical performance.

  20. Exact diagonalization of the Bohr Hamiltonian for rotational nuclei: Dynamical {gamma} softness and triaxiality

    SciTech Connect

    Caprio, M. A.

    2011-06-15

    Detailed quantitative predictions are obtained for phonon and multiphonon excitations in well-deformed rotor nuclei within the geometric framework, by exact numerical diagonalization of the Bohr Hamiltonian in an SO(5) basis. Dynamical {gamma} deformation is found to significantly influence the predictions through its coupling to the rotational motion. Basic signatures for the onset of rigid triaxial deformation are also obtained.

  1. Comparison of Mechanical Properties of Fiber-Reinforced Sand under Triaxial Compression and Direct Shear

    NASA Astrophysics Data System (ADS)

    Noorzad, Reza; Zarinkolaei, Seyed Taher Ghoreyshi

    2015-10-01

    This research investigates the behavior of sand reinforced with polypropylene fiber. To do this, 40 direct shear tests and 40 triaxial tests were performed on the coastal beaches of Babolsar, a city in the North of Iran. The effect of parameters such as fiber content, length of fiber and normal or confining pressure on the behavior of Babolsar sand have been studied. In this study, four various fiber contents (0, 0.25, 0.5 and 1 percent), three different lengths of fiber (6, 12 and 18 mm) and four normal or confining pressures (50, 100, 200 and 400 kPa) have been employed. The test results show that fiber inclusion has a significant effect on the behavior of sand. In both direct shear and triaxial tests, the addition of fibers improved shear strength parameters (C, '), increased peak shear strength and axial strain at failure, and also limited the amount of post-peak reduction in shear resistance. The comparison of the test results revealed that due to better fiber orientation toward the direction of principal tensile strain in triaxial test as compared to direct shear tests, the fiber efficiency and its effect on soil behavior is much more significant in triaxial specimens.

  2. Experimental study on properties of methane diffusion of coal block under triaxial compressive stress.

    PubMed

    Zhao, Hong-Bao

    2014-01-01

    Taking the standard size coal block samples defined by ISRM as research objects, both properties of methane diffusion of coal block under triaxial compressive stress and characteristic influences caused by methane pressure were systematically studied with thermo-fluid-solid coupling with triaxial servocontrolled seepage equipment of methane-containing coal. The result shows the methane diffusion property of coal block under triaxial compressive stress was shown in four-stage as follow, first is sharply reduce stage, second is hyperbolic reduce stage, third is close to a fixed value stage, fourth stage is 0. There is a special point making the reduced rate of characteristic curve of methane diffusion speed become sharply small; the influences of shape of methane diffusion speed characteristic curve caused by methane pressure are not obvious, which only is shown in numerical size of methane diffusion speed. Test time was extended required by appear of the special point makes the reduce rate of methane diffusion speed become sharply small. The fitting four-phase relation of methane diffusion of coal block under triaxial compressive stress was obtained, and the idea is proposed that influences of the fitting four-phase relation caused by methane pressure were only shown in value of fitting parameters.

  3. Experimental Study on Properties of Methane Diffusion of Coal Block under Triaxial Compressive Stress

    PubMed Central

    Zhao, Hong-Bao

    2014-01-01

    Taking the standard size coal block samples defined by ISRM as research objects, both properties of methane diffusion of coal block under triaxial compressive stress and characteristic influences caused by methane pressure were systematically studied with thermo-fluid-solid coupling with triaxial servocontrolled seepage equipment of methane-containing coal. The result shows the methane diffusion property of coal block under triaxial compressive stress was shown in four-stage as follow, first is sharply reduce stage, second is hyperbolic reduce stage, third is close to a fixed value stage, fourth stage is 0. There is a special point making the reduced rate of characteristic curve of methane diffusion speed become sharply small; the influences of shape of methane diffusion speed characteristic curve caused by methane pressure are not obvious, which only is shown in numerical size of methane diffusion speed. Test time was extended required by appear of the special point makes the reduce rate of methane diffusion speed become sharply small. The fitting four-phase relation of methane diffusion of coal block under triaxial compressive stress was obtained, and the idea is proposed that influences of the fitting four-phase relation caused by methane pressure were only shown in value of fitting parameters. PMID:25531000

  4. Acoustic-emissive memory effect in coal samples under triaxial axial-symmetric compression

    SciTech Connect

    Shkuratnik, V.L.; Filimonov, Y.L.; Kuchurin, S.V.

    2006-05-15

    The experimental data are presented for production and manifestation of the Kaiser effect in coal samples subjected to triaxial loading by the Karman scheme in the first cycle and to various loading modes in the second cycle. The Kaiser effect is identified with the help of a deformation memory effect.

  5. Features of the Kaiser effect in coal specimens at different stages of the triaxial axisymmetric deformation

    SciTech Connect

    Shkuratnik, V.L.; Filimonov, Y.L.; Kuchurin, S.V.

    2007-01-15

    The experimental data are presented for the features of formation and manifestation of the acoustic-emission and deformation memory effects in specimens of anthracite at different stages of the triaxial cyclic deformation by the Karman scheme in the pre-limiting and post-limiting zones.

  6. On the Components of Segregation Distortion in Drosophila Melanogaster. V. Molecular Analysis of the Sd Locus

    PubMed Central

    Powers, P. A.; Ganetzky, B.

    1991-01-01

    Segregation Distorter (SD) is a naturally occurring meiotic drive system comprising at least three distinct loci: Sd, Rsp and E(SD). Heterozygous SD/SD(+) males transmit the SD chromosome in vast excess over the normal homolog. The distorted transmission involves the induced dysfunction of the spermatids that receive the SD(+) chromosome. In the 220-kb region of DNA that contains the Sd gene, we identified a 5-kb tandem duplication that is uniquely associated with all SD chromosomes, absent in SD(+) chromosomes, and detectably altered in Sd revertants. On northern blots, genomic probes from the tandem duplication detect an SD-specific 4-kb transcript in addition to several smaller transcripts present in both SD and SD(+). Seven classes of cDNAs derived from these transcripts have been isolated. All of these cDNAs share extensive sequence identity at their 3' ends but differ at their 5' ends. Sequence analysis indicates that these cDNAs potentially encode four distinct, but related, polypeptides. Introduction of the tandem duplication into SD(+) flies by germline transformation did not confer the dominant gain-of-function Sd phenotype. This result, taken together with our analysis of the Sd cDNAs, suggests that the duplication is part of a much larger gene that encodes several different polypeptides. PMID:1936954

  7. Differential binding of human blood group Sd(a+) and Sd(a-) Tamm-Horsfall glycoproteins with Dolichos biflorus and Vicia villosa-B4 agglutinins.

    PubMed

    Wu, A M; Wu, J H; Watkins, W M; Chen, C P; Song, S C; Chen, Y Y

    1998-06-16

    The binding patterns of human blood group Sd(a+) and Sd(a-) Tamm-Horsfall glycoproteins (THGPs) with respect to four GalNAc specific agglutinins were studied by quantitative precipitin assay (QPA) and enzyme linked lectinosorbent assay (ELLSA). Of the native and asialo Sd(a+) and Sd(a-) THGP tested by QPA and ELLSA, only native and asialo Sd(a+) bound well with Dolichos biflorus (DBA) and Vicia villosa-B4 (VVA-B4), while Sd(a-) THGP reacted poorly with these two lectins. Neither Sd(a+) nor Sd(a-) THGPs reacted with two other GalNAc alpha-anomer specific lectins: Codium fragile subspecies tomentosoides and Artocarpus integrifolia. Furthermore, the binding of asialo Sd(a+)THGP-VVA-B4 and native Sd(a+)THGP-DBA through GalNAc beta--> was confirmed by inhibition assay. These results demonstrate that DBA and VVA-B4 are useful reagents to differentiate between Sd(a+) and Sd(a-) THGP.

  8. Complex dynamics of an archetypal self-excited SD oscillator driven by moving belt friction

    NASA Astrophysics Data System (ADS)

    Zhi-Xin, Li; Qing-Jie, Cao; Léger, Alain

    2016-01-01

    We propose an archetypal self-excited system driven by moving belt friction, which is constructed with the smooth and discontinuous (SD) oscillator proposed by the Cao et al. and the classical moving belt. The moving belt friction is modeled as the Coulomb friction to formulate the mathematical model of the proposed self-excited SD oscillator. The equilibrium states of the unperturbed system are obtained to show the complex equilibrium bifurcations. Phase portraits are depicted to present the hyperbolic structure transition, the multiple stick regions, and the friction-induced asymmetry phenomena. The numerical simulations are carried out to demonstrate the friction-induced vibration of multiple stick-slip phenomena and the stick-slip chaos in the perturbed self-excited system. The results presented here provide an opportunity for us to get insight into the mechanism of the complex friction-induced nonlinear dynamics in mechanical engineering and geography. Project supported by the National Natural Science Foundation of China (Grant Nos. 11372082 and 11572096) and the National Basic Research Program of China (Grant No. 2015CB057405).

  9. Automated Drusen Segmentation and Quantification in SD-OCT Images

    PubMed Central

    Chen, Qiang; Leng, Theodore; Zheng, Luoluo; Kutzscher, Lauren; Ma, Jeffrey; de Sisternes, Luis; Rubin, Daniel L.

    2013-01-01

    Spectral domain optical coherence tomography (SD-OCT) is a useful tool for the visualization of drusen, a retinal abnormality seen in patients with age-related macular degeneration (AMD); however, objective assessment of drusen is thwarted by the lack of a method to robustly quantify these lesions on serial OCT images. Here, we describe an automatic drusen segmentation method for SD-OCT retinal images, which leverages a priori knowledge of normal retinal morphology and anatomical features. The highly reflective and locally connected pixels located below the retinal nerve fiber layer (RNFL) are used to generate a segmentation of the retinal pigment epithelium (RPE) layer. The observed and expected contours of the RPE layer are obtained by interpolating and fitting the shape of the segmented RPE layer, respectively. The areas located between the interpolated and fitted RPE shapes (which have nonzero area when drusen occurs) are marked as drusen. To enhance drusen quantification, we also developed a novel method of retinal projection to generate an en face retinal image based on the RPE extraction, which improves the quality of drusen visualization over the current approach to producing retinal projections from SD-OCT images based on a summed-voxel projection (SVP), and it provides a means of obtaining quantitative features of drusen in the en face projection. Visualization of the segmented drusen is refined through several post-processing steps, drusen detection to eliminate false positive detections on consecutive slices, drusen refinement on a projection view of drusen, and drusen smoothing. Experimental evaluation results demonstrate that our method is effective for drusen segmentation. In a preliminary analysis of the potential clinical utility of our methods, quantitative drusen measurements, such as area and volume, can be correlated with the drusen progression in non-exudative AMD, suggesting that our approach may produce useful quantitative imaging biomarkers

  10. Development of a triaxially formed fabric for use in an improved restraint layer in the shuttle space suit

    NASA Technical Reports Server (NTRS)

    1977-01-01

    A series of materials for use as an improved restraint layer in the shuttle space suit was developed. The feasibility of weaving triaxial fabrics in tight, low porosity configurations with yarns of appropriate sizes and materials was demonstrated along with the stability and isotropy of triaxial fabrics. The triaxial fabric constructions, BP44P and BP40M, can be reproduced on a production basis. Both fabric constructions afford excellent strength-to-weight ratio and exhibit improved tear strength and shear resistance over biaxial fabrics.

  11. Comparisons of interacting-boson-fermion approximation and triaxial calculations for odd-mass N =80 nuclei

    SciTech Connect

    Aryaeinejad, R.; Chou, W.; McHarris, W.C. )

    1989-09-01

    The interacting-boson-fermion-approximation and triaxial models were used to calculate excitation energies and mixing ratios for the {ital N}=80 nuclei, {sup 139}Pr, {sup 141}Pm, and {sup 143}Eu. For low-lying negative- and positive-parity states both models yield roughly the same numbers, in good agreement with experimental results. For high-lying states we find that the interacting-boson-fermion-approximation model describes the level structure considerably better than the triaxial model. On the other hand, the triaxial model gives more satisfactory results in predicting the mixing ratios.

  12. FUSE Observations of He-rich sdB Stars

    NASA Technical Reports Server (NTRS)

    Swiegart, A. V.; Lanz, T.; Brown, T. M.; Hubeny, I.; Landsman, W. B.

    2003-01-01

    Most subdwarf B stars are extremely deficient in helium and selected light elements, but a minority are helium-rich. New evolutionary calculations suggest that these helium-rich sdB stars are the result of a delayed helium-core flash on the white dwarf cooling curve, which leads to extensive mixing between the hydrogen envelope and helium core. Such mixed stars should show greatly enhanced helium and carbon with respect to the other heavy elements. We have recently obtained FUSE spectra of two helium-rich sdB stars, PG1544+488 and JL87, revealing huge C Ill lines at 977 and 1176 A. Our analysis shows that PG1544+488 has a surface composition of 97% He, 2% C, and 1% N, in agreement with the new evolutionary scenario. While JL87 also reveals a large enrichment in carbon and nitrogen (1.4% and 0.4%, respectively), there is still a significant amount of hydrogen in its atmosphere.

  13. DETECTING TRIAXIALITY IN THE GALACTIC DARK MATTER HALO THROUGH STELLAR KINEMATICS

    SciTech Connect

    Rojas-Nino, Armando; Valenzuela, Octavio; Pichardo, Barbara; Aguilar, Luis A. E-mail: barbara@astro.unam.mx

    2012-10-01

    Assuming the dark matter halo of the Milky Way to be a non-spherical potential (i.e., triaxial, prolate, oblate), we show how the assembling process of the Milky Way halo may have left long-lasting stellar halo kinematic fossils due to the shape of the dark matter halo. In contrast with tidal streams, which are associated with recent satellite accretion events, these stellar kinematic groups will typically show inhomogeneous chemical and stellar population properties. However, they may be dominated by a single accretion event for certain mass assembling histories. If the detection of these peculiar kinematic stellar groups were confirmed, they would be the smoking gun for the predicted triaxiality of dark halos in cosmological galaxy formation scenarios.

  14. Evidence for a Triaxial Milky Way Dark Matter Halo from the Sagittarius Stellar Tidal Stream

    NASA Astrophysics Data System (ADS)

    Law, David R.; Majewski, S. R.; Johnston, K. V.

    2010-01-01

    Observations of the lengthy tidal streams produced by the destruction of the Sagittarius dwarf spheroidal galaxy (Sgr dSph) are capable of providing strong constraints on the shape of the Galactic gravitational potential. However, previous work, based on modeling different stream properties in axisymmetric Galactic models has yielded conflicting results: while the angular precession of the Sgr leading arm is most consistent with a spherical or slightly oblate halo, the radial velocities of stars in this arm are only reproduced by prolate halo models. We demonstrate that this apparent paradox can be resolved by instead adopting a triaxial potential. Our new Galactic halo model, which simultaneously fits all well-established phase space constraints from the Sgr stream, provides the first conclusive evidence for, and tentative measurement of, triaxiality in an individual dark matter halo. In this model, the minor axis of the dark halo is approximately coincident with the Galactic X axis connecting the Sun and the Galactic Center.

  15. Design of a piezoresistive triaxial force sensor probe using the sidewall doping method

    NASA Astrophysics Data System (ADS)

    Kan, Tetsuo; Takahashi, Hidetoshi; Binh-Khiem, Nguyen; Aoyama, Yuichiro; Takei, Yusuke; Noda, Kentaro; Matsumoto, Kiyoshi; Shimoyama, Isao

    2013-03-01

    In this study, we propose a triaxial force measurement sensor probe with piezoresistors fabricated via sidewall doping using rapid thermal diffusion. The device was developed as a tool for measuring micronewton-level forces as vector quantities. The device consists of a 15 µm thick cantilever, two sensing beams and four wiring beams. The length and width of the cantilever are 1240 µm and 140 µm, respectively, with a beam span of 1200 µm and a width of 10-15 µm. The piezoresistors are formed at the root of the cantilever and the sidewalls of the two sensing beams. The sensor spring constants for each axis were measured at kx = 1.5 N m-1, ky = 3.5 N m-1 and kz = 0.64 N m-1. We confirmed that our device was capable of measuring triaxial forces with a minimum detectable force at the submicronewton level.

  16. Molecular dynamics simulations of void effect of the copper nanocubes under triaxial tensions

    NASA Astrophysics Data System (ADS)

    Yang, Zailin; Zhang, Guowei; Zhao, Jianwei

    2016-02-01

    The isotropic copper nanocubes with different size cubic voids under triaxial tensions are investigated by the molecular dynamics method. For accuracy we present the hydrostatic stress, Mises stress, true stress, logarithmic strain and relationship between each other. In the simulation the number of model atoms is formulized and the hydrostatic stresses can replace triaxial stresses of model. We demonstrate that the yielding strengths will decrease with increase of void, particularly when the void percentage is reaching 0.2%. The models are breaking at 45 angle dislocation with tiny differences. Also, the Gurson model cannot well describe the trend of damage; instead the authors propose a modified model by relationship between Mises stress and hydrostatic stress.

  17. Motion in the ER3BP with an oblate primary and a triaxial stellar companion

    NASA Astrophysics Data System (ADS)

    Umar, Aishetu; Hussain, Aminu Abubakar

    2016-10-01

    The triangular points of the elliptic restricted three-body problem under an oblate primary and a triaxial and radiating secondary are investigated. Their positions and stability are found to be affected by the eccentricity, semi-major axis, oblateness, triaxiality and radiation pressure. Using Low and High Mass X-ray binaries (LMXB and HMXB), we highlight the effects of the said parameters on the positions of the triangular points of PSR J1903+0327, CEN X-4 and RXJ 04050.01.5658. The triangular points are found to be stable for 0 < μ < μC; where μ is the mass ratio ( μ ≤ 1/2 ). The effects of the parameters on the regions of stability are shown graphically within the stable interval, highlighting their destabilizing tendencies.

  18. Nanofibers Fabricated Using Triaxial Electrospinning as Zero Order Drug Delivery Systems.

    PubMed

    Yu, Deng-Guang; Li, Xiao-Yan; Wang, Xia; Yang, Jun-He; Bligh, S W Annie; Williams, Gareth R

    2015-08-26

    A new strategy for creating functional trilayer nanofibers through triaxial electrospinning is demonstrated. Ethyl cellulose (EC) was used as the filament-forming matrix in the outer, middle, and inner working solutions and was combined with varied contents of the model active ingredient ketoprofen (KET) in the three fluids. Triaxial electrospinning was successfully carried out to generate medicated nanofibers. The resultant nanofibers had diameters of 0.74 ± 0.06 μm, linear morphologies, smooth surfaces, and clear trilayer nanostructures. The KET concentration in each layer gradually increased from the outer to the inner layer. In vitro dissolution tests demonstrated that the nanofibers could provide linear release of KET over 20 h. The protocol reported in this study thus provides a facile approach to creating functional nanofibers with sophisticated structural features.

  19. Biological Parameters and the Segregation Distortion (SD) Phenomenon in DROSOPHILA MELANOGASTER

    PubMed Central

    Trippa, G.; Cicchetti, R.; Loverre, A.; Micheli, A.

    1981-01-01

    The relationship between some biological parameters (mortality, longevity, fertility, fecundity and sex ratio) and segregation of second chromosomes in heterozygous and homozygous SD males has been analyzed. The results obtained in SD/SD+ heterozygous males show: (1) their reduced fertility with respect to that of control males, (2) an alteration in the sex ratio in the SD+ progeny only, and (3) inversely related sex-ratio and segregation distortion values. In SDi/SDj combinations: (1) surprisingly, fertility is intermediate between that of SD/SD+ heterozygous males and that of control males, (2) the segregation ratios of the second chromosomes are normal (0.50), and (3) the sex ratio = 0.50 in both classes of SD progeny. The relationship between mortality (and therefore longevity) and fertility of the different genotypes and fecundity per male indicates that the total productivity of heterozygous males is less than that so far claimed. Indeed, their productivity depends not only on the mechanism of nonformation of the SD+ sperm, but also on their reduced longevity. The k = 0.50 and the high fecundity of SDi/SDj combinations indicate that in these males the SD phenomenon is partially suppressed, the SD chromosomes being insensitive to each other, thus implying that particular Rsp alleles are sensitive to given Sd alleles. The complementation pattern for male fertility of SD homozygous males again supports previous evidence that Sd factors from natural populations are, in effect, different Sd genes. PMID:6795081

  20. The planar restricted three-body problem when both primaries are triaxial rigid bodies: Equilibrium points and periodic orbits

    NASA Astrophysics Data System (ADS)

    Elshaboury, S. M.; Abouelmagd, Elbaz I.; Kalantonis, V. S.; Perdios, E. A.

    2016-09-01

    The restricted three-body problem when the primaries are triaxial rigid bodies is considered and its basic dynamical features are studied. In particular, the equilibrium points are identified as well as their stability is determined in the special case when the Euler angles of rotational motion are accordingly θi = ψi = π/2 and φi = π/2, i = 1, 2. It is found that three unstable collinear equilibrium points exist and two triangular such points which may be stable. Special attention has also been paid to the study of simple symmetric periodic orbits and 31 families consisting of such orbits have been determined. It has been found that only one of these families consists entirely of unstable members while the remaining families contain stable parts indicating that other families bifurcate from them. Finally, using the grid-search technique a global solution in the space of initial conditions is obtained which comprises simple and of higher multiplicities symmetric periodic orbits as well as escape and collision orbits.

  1. Triaxial shape with rotation around the longest principal axis in Gd142

    NASA Astrophysics Data System (ADS)

    Carlsson, B. G.; Ragnarsson, I.; Bengtsson, R.; Lieder, E. O.; Lieder, R. M.; Pasternak, A. A.

    2008-09-01

    The cranking model is used to describe rotational bands. We investigate the approach of using diabatic configurations and minimizing the particle-number projected energy in a mesh of both λ,Δ and deformation parameters. We use the method to interpret recent experimental data in Gd142 and conclude that for the highest spin states observed (I≈30), the nucleus is triaxial and builds spin by rotating around the classically unfavored longest axis.

  2. Experimental observation of dynamic ductile damage development under various triaxiality conditions - description of the principle

    NASA Astrophysics Data System (ADS)

    Pillon, L.

    2012-08-01

    The Gurson model has been extended by Perrin to describe damage evolution in ductile viscoplastic materials. The so-called Gurson-Perrin model allows representing damage development with respect to strain-rate conditions. In order to fill a lack in current experimental procedures, we propose an experimental project able to test and validate the Gurson-Perrin model under various dynamic conditions and for different stress triaxiality levels.

  3. Open sd-shell nuclei from first principles

    DOE PAGESBeta

    Jansen, Gustav R.; Signoracci, Angelo J.; Hagen, Gaute; Navratil, Petr

    2016-07-05

    We extend the ab initio coupled-cluster e ective interaction (CCEI) method to open-shell nuclei with protons and neutrons in the valence space, and compute binding energies and excited states of isotopes of neon and magnesium. We employ a nucleon-nucleon and three-nucleon interaction from chiral e ective eld theory evolved to a lower cuto via a similarity renormalization group transformation. We nd good agreement with experiment for binding energies and spectra, while charge radii of neon isotopes are underestimated. For the deformed nuclei 20Ne and 24Mg we reproduce rotational bands and electric quadrupole transitions within uncertainties estimated from an e ectivemore » eld theory for deformed nuclei, thereby demonstrating that collective phenomena in sd-shell nuclei emerge from complex ab initio calculations.« less

  4. Study on the Particle Size Distribution Nano-Particles of Mining Minerals on Whiteness of Triaxial Body

    NASA Astrophysics Data System (ADS)

    Mathur, Ravi; Soni, Aditi

    White wares produced worldwide represent the foundation of much of the ceramic industry; Porcelain bodies fabricated from triaxial mixtures of clay, quartz and feldspar with different size and amounts of nano particles were investigated. Although the purity of raw materials has a strong effect on the colour of the fired bodies, the particle size of raw materials also effect the whiteness The raw material mining minerals china Clay, Feldspar, quarts were prepared of various sized nano particles contains 10.60 -20.22%, 56.84- 70.80 % and 34.87-50.76 % of 100nm respectively. The fired bodies of raw mining minerals and triaxial bodies were subjected to colour measurement. The differences in whiteness were compared and discussed. The studies so far carried out is upto 400 mesh size while the present study has included up to 100nm particle size. A statistical correlation between whiteness of feldspar and triaxial body was also carried out. The correlation between china clay and triaxial body are 0.53, 0.57 and 0.66 for china clay similarly correlation for feldspar is 0.49, 0.73 and 0.83 for triaxial body it are 0.97, 0.84 and 0.75 for A1, A2 and A3 samples. Correlation between china clay and feldspar with triaxial body are 0.79 and 0.92 respectively.

  5. The Effects of Stress Triaxiality, Temperature and Strain Rate on the Fracture Characteristics of a Nickel-Base Superalloy

    NASA Astrophysics Data System (ADS)

    Wang, Jianjun; Guo, Weiguo; Guo, Jin; Wang, Ziang; Lu, Shengli

    2016-05-01

    In this work, to study the effects of stress triaxiality, temperature, and strain rate on the fracture behaviors of a single-crystal Nickel-base superalloy, a series of experiments over a temperature range of 293 to 1373 K, strain rate range of 0.001 to 4000/s, and stress triaxiality range of -0.6 to 1.1 are conducted. Anomalous peak of stress is noticed in the yield stress versus temperature curves, and strain rate effect on the anomalous peak of yield stress is analyzed. The anomalous peak shifts to higher temperature as the strain rate increases. Then the effects of stress triaxiality, temperature, and strain rate on its fracture behaviors, including strain to fracture, path of crack propagation, and fracture surface, are observed and analyzed. A valley of the fracture strain is formed in the fracture strain versus temperature curve over the selected temperature range. The micrograph of fracture surface is largely dependent on the temperature, stress triaxiality, and strain rate. Finally, the original Johnson-Cook (J-C) fracture criterion cannot describe the effect of stress triaxiality and temperature on the fracture behaviors of single-crystal Nickel-base superalloy. A modified J-C fracture criterion is developed, which takes the anomalous stress triaxiality and temperature effects on the fracture behaviors of single-crystal Nickel-base superalloy into account.

  6. Charge radii of neon isotopes across the sd neutron shell

    SciTech Connect

    Marinova, K.; Geithner, W.; Kappertz, S.; Kloos, S.; Kotrotsios, G.; Neugart, R.; Wilbert, S.; Kowalska, M.; Keim, M.; Blaum, K.; Lievens, P.; Simon, H.

    2011-09-15

    We report on the changes in mean square charge radii of unstable neon nuclei relative to the stable {sup 20}Ne, based on the measurement of optical isotope shifts. The studies were carried out using collinear laser spectroscopy on a fast beam of neutral neon atoms. High sensitivity on short-lived isotopes was achieved thanks to nonoptical detection based on optical pumping and state-selective collisional ionization, which was complemented by an accurate determination of the beam kinetic energy. The new results provide information on the structural changes in the sequence of neon isotopes all across the neutron sd shell, ranging from the proton drip line nucleus and halo candidate {sup 17}Ne up to the neutron-rich {sup 28}Ne in the vicinity of the ''island of inversion.'' Within this range the charge radius is smallest for {sup 24}Ne with N=14 corresponding to the closure of the neutron d{sub 5/2} shell, while it increases toward both neutron shell closures, N=8 and N=20. The general trend of the charge radii correlates well with the deformation effects which are known to be large for several neon isotopes. In the neutron-deficient isotopes, structural changes arise from the onset of proton-halo formation for {sup 17}Ne, shell closure in {sup 18}Ne, and clustering effects in {sup 20,21}Ne. On the neutron-rich side the transition to the island of inversion plays an important role, with the radii in the upper part of the sd shell confirming the weakening of the N=20 magic number. The results add new information to the radii systematics of light nuclei where data are scarce because of the small contribution of nuclear-size effects to the isotope shifts which are dominated by the finite-mass effect.

  7. Falls classification using tri-axial accelerometers during the five-times-sit-to-stand test.

    PubMed

    Doheny, Emer P; Walsh, Cathal; Foran, Timothy; Greene, Barry R; Fan, Chie Wei; Cunningham, Clodagh; Kenny, Rose Anne

    2013-09-01

    The five-times-sit-to-stand test (FTSS) is an established assessment of lower limb strength, balance dysfunction and falls risk. Clinically, the time taken to complete the task is recorded with longer times indicating increased falls risk. Quantifying the movement using tri-axial accelerometers may provide a more objective and potentially more accurate falls risk estimate. 39 older adults, 19 with a history of falls, performed four repetitions of the FTSS in their homes. A tri-axial accelerometer was attached to the lateral thigh and used to identify each sit-stand-sit phase and sit-stand and stand-sit transitions. A second tri-axial accelerometer, attached to the sternum, captured torso acceleration. The mean and variation of the root-mean-squared amplitude, jerk and spectral edge frequency of the acceleration during each section of the assessment were examined. The test-retest reliability of each feature was examined using intra-class correlation analysis, ICC(2,k). A model was developed to classify participants according to falls status. Only features with ICC>0.7 were considered during feature selection. Sequential forward feature selection within leave-one-out cross-validation resulted in a model including four reliable accelerometer-derived features, providing 74.4% classification accuracy, 80.0% specificity and 68.7% sensitivity. An alternative model using FTSS time alone resulted in significantly reduced classification performance. Results suggest that the described methodology could provide a robust and accurate falls risk assessment.

  8. DOES THE SAGITTARIUS STREAM CONSTRAIN THE MILKY WAY HALO TO BE TRIAXIAL?

    SciTech Connect

    Ibata, R.; Martin, N. F.; Lewis, G. F.; Bellazzini, M.; Correnti, M.

    2013-03-01

    Recent analyses of the stellar stream of the Sagittarius dwarf galaxy have suggested that the kinematics and three-dimensional location of the M-giant stars in this structure constrain the dark matter halo of our Galaxy to possess a triaxial shape that is extremely flattened, being essentially an oblate ellipsoid oriented perpendicular to the Galactic disk. Using a new stream-fitting algorithm, based on a Markov Chain Monte Carlo procedure, we investigate whether this claim remains valid if we allow the density profile of the Milky Way halo greater freedom. We find stream solutions that fit the leading and trailing arms of this structure even in a spherical halo, although this would need a rising Galactic rotation curve at large Galactocentric radius. However, the required rotation curve is not ruled out by current constraints. It appears therefore that for the Milky Way, halo triaxiality, despite its strong theoretical motivation, is not required to explain the Sagittarius stream. This degeneracy between triaxiality and the halo density profile suggests that, in future endeavors to model this structure, it will be advantageous to relax the strict analytic density profiles that have been used to date.

  9. Experimental Study of Slabbing and Rockburst Induced by True-Triaxial Unloading and Local Dynamic Disturbance

    NASA Astrophysics Data System (ADS)

    Du, Kun; Tao, Ming; Li, Xi-bing; Zhou, Jian

    2016-09-01

    Slabbing/spalling and rockburst are unconventional types of failure of hard rocks under conditions of unloading and various dynamic loads in environments with high and complex initial stresses. In this study, the failure behaviors of different rock types (granite, red sandstone, and cement mortar) were investigated using a novel testing system coupled to true-triaxial static loads and local dynamic disturbances. An acoustic emission system and a high-speed camera were used to record the real-time fracturing processes. The true-triaxial unloading test results indicate that slabbing occurred in the granite and sandstone, whereas the cement mortar underwent shear failure. Under local dynamically disturbed loading, none of the specimens displayed obvious fracturing at low-amplitude local dynamic loading; however, the degree of rock failure increased as the local dynamic loading amplitude increased. The cement mortar displayed no failure during testing, showing a considerable load-carrying capacity after testing. The sandstone underwent a relatively stable fracturing process, whereas violent rockbursts occurred in the granite specimen. The fracturing process does not appear to depend on the direction of local dynamic loading, and the acoustic emission count rate during rock fragmentation shows that similar crack evolution occurred under the two test scenarios (true-triaxial unloading and local dynamically disturbed loading).

  10. A High Performance Sensor for Triaxial Cutting Force Measurement in Turning

    PubMed Central

    Zhao, You; Zhao, Yulong; Liang, Songbo; Zhou, Guanwu

    2015-01-01

    This paper presents a high performance triaxial cutting force sensor with excellent accuracy, favorable natural frequency and acceptable cross-interference for high speed turning process. Octagonal ring is selected as sensitive element of the designed sensor, which is drawn inspiration from ring theory. A novel structure of two mutual-perpendicular octagonal rings is proposed and three Wheatstone full bridge circuits are specially organized in order to obtain triaxial cutting force components and restrain cross-interference. Firstly, the newly developed sensor is tested in static calibration; test results indicate that the sensor possesses outstanding accuracy in the range of 0.38%–0.83%. Secondly, impacting modal tests are conducted to identify the natural frequencies of the sensor in triaxial directions (i.e., 1147 Hz, 1122 Hz and 2035 Hz), which implies that the devised sensor can be used for cutting force measurement in a high speed lathe when the spindle speed does not exceed 17,205 rev/min in continuous cutting condition. Finally, an application of the sensor in turning process is operated to show its performance for real-time cutting force measurement; the measured cutting forces demonstrate a good accordance with the variation of cutting parameters. Thus, the developed sensor possesses perfect properties and it gains great potential for real-time cutting force measurement in turning. PMID:25855035

  11. What's up in the Milky Way? The orientation of the disc relative to the triaxial halo

    NASA Astrophysics Data System (ADS)

    Debattista, Victor P.; Roškar, Rok; Valluri, Monica; Quinn, Thomas; Moore, Ben; Wadsley, James

    2013-10-01

    Models of the Sagittarius stream have consistently found that the Milky Way disc is oriented such that its short axis is along the intermediate axis of the triaxial dark matter halo. We attempt to build models of disc galaxies in such an `intermediate-axis orientation'. We do this with three models. In the first two cases we simply rigidly grow a disc in a triaxial halo such that the disc ends up perpendicular to the global intermediate axis. We also attempt to coax a disc to form in an intermediate-axis orientation by producing a gas+dark matter triaxial system with gas angular momentum about the intermediate axis. In all cases we fail to produce systems which remain with stellar angular momentum aligned with the halo's intermediate axis, even when the disc's potential flattens the inner halo such that the disc is everywhere perpendicular to the halo's local minor axis. For one of these unstable simulations we show that the potential is even rounder than the models of the Milky Way potential in the region probed by the Sagittarius stream. We conclude that the Milky Way's disc is very unlikely to be in an intermediate-axis orientation. However we find that a disc can persist off one of the principal planes of the potential. We propose that the disc of the Milky Way must be tilted relative to the principal axes of the dark matter halo. Direct confirmation of this prediction would constitute a critical test of Modified Newtonian Dynamics.

  12. Evidence for a Triaxial Milky Way Dark Matter Halo from the Sagittarius Stellar Tidal Stream

    NASA Astrophysics Data System (ADS)

    Law, David R.; Majewski, Steven R.; Johnston, Kathryn V.

    2009-09-01

    Observations of the lengthy tidal streams produced by the destruction of the Sagittarius dwarf spheroidal (Sgr dSph) are capable of providing strong constraints on the shape of the Galactic gravitational potential. However, previous work, based on modeling different stream properties in axisymmetric Galactic models, has yielded conflicting results: while the angular precession of the Sgr leading arm is most consistent with a spherical or slightly oblate halo, the radial velocities of stars in this arm are reproduced only by prolate halo models. We demonstrate that this apparent paradox can be resolved by instead adopting a triaxial potential. Our new Galactic halo model, which simultaneously fits all well-established phase space constraints from the Sgr stream, provides the first conclusive evidence for, and tentative measurement of, triaxiality in an individual dark matter halo. The Milky Way halo within ~60 kpc is best characterized by a minor/major axis ratio of the isovelocity contours c/a ≈ 0.67, intermediate/major axis ratio b/a ≈ 0.83, and triaxiality parameter T ~ 0.56. In this model, the minor axis of the dark halo is coincident with the Galactic X-axis connecting the Sun and the Galactic center to within ~15°, while the major axis also lies in the Galactic plane, approximately along the Galactic Y-axis.

  13. Full-Field Strain Methods for Investigating Failure Mechanisms in Triaxial Braided Composites

    NASA Technical Reports Server (NTRS)

    Littell, Justin D.; Binienda, Wieslaw K.; Goldberg, Robert K.; Roberts, Gary D.

    2008-01-01

    Recent advancements in braiding technology have led to commercially viable manufacturing approaches for making large structures with complex shape out of triaxial braided composite materials. In some cases, the static load capability of structures made using these materials has been higher than expected based on material strength properties measured using standard coupon tests. A more detailed investigation of deformation and failure processes in large-unit-cell-size triaxial braid composites is needed to evaluate the applicability of standard test methods for these materials and to develop alternative testing approaches. This report presents some new techniques that have been developed to investigate local deformation and failure using digital image correlation techniques. The methods were used to measure both local and global strains during standard straight-sided coupon tensile tests on composite materials made with 12- and 24-k yarns and a 0 /+60 /-60 triaxial braid architecture. Local deformation and failure within fiber bundles was observed and correlations were made between these local failures and global composite deformation and strength.

  14. Experimental observation of dynamic ductile damage development under various triaxiality conditions

    NASA Astrophysics Data System (ADS)

    Pillon, Laurianne; Adolf, Lise-Marie

    2015-06-01

    Fracture in ductile materials finds its origin in microscopic mechanisms: the nucleation of voids that grow and coalesce in order to form a crack. The most popular of these models, proposed by Gurson, aims at describing the damage development with respect to the plastic behavior of porous material. The Gurson model has been extended by Perrin to describe damage evolution in ductile viscoplastic porous materials. The Gurson-Perrin model (GPm) allows representing damage development with respect to the stress triaxiality and strain-rate conditions. We propose a new experimental design able to test and validate the GPm under various dynamic conditions and for different triaxiality levels. The experimental project will be detailed. A notch is drawn in the Cu cylindrical target where damage develops and the local failure occurs. A variation of the notch radius enables a variation in the triaxiality level. Three notch radii have been tested. Observations with numerical cameras allow following the shape of the notch, a characteristic of damage development. Several PDV measurements have been performed around the target. A first analysis of this experimental process will be shown and comparisons with numerical simulations will be presented.

  15. Fully alternating, triaxial electric or magnetic fields offer new routes to fluid vorticity

    DOE PAGESBeta

    Martin, James E.; Solis, Kyle J.

    2014-10-31

    Noncontact methods of generating strong fluid vorticity are important to problems involving heat and mass transfer, fluid mixing, active wetting, and droplet transport. Furthermore, because zero or even negative shear viscosities can be induced, vorticity can greatly extend the control range of the smart fluids used in magnetorheological devices. In recent work we have shown that a particular class of ac/ac/dc triaxial fields (so-called symmetry-breaking rational fields) can create strong vorticity in magnetic particle suspensions and have presented a theory of the vorticity that is based on the symmetry of the 2-d Lissajous trajectories of the field and its converse.more » In this paper we demonstrate that there are three countably infinite sets of fully alternating ac/ac/ac triaxial fields whose frequencies form rational triads that have the symmetry required to drive fluid vorticity. The symmetry of the 3-d Lissajous trajectories of the field and its converse can be derived and from this the direction of the vorticity axis can be predicted, as can the dependence of the sign of the vorticity on the phase relations between the three field components. Experimental results are presented that validate the symmetry theory. These discoveries significantly broaden the class of triaxial fields that can be exploited to produce strong noncontact flow.« less

  16. Fully alternating, triaxial electric or magnetic fields offer new routes to fluid vorticity

    SciTech Connect

    Martin, James E.; Solis, Kyle J.

    2014-10-31

    Noncontact methods of generating strong fluid vorticity are important to problems involving heat and mass transfer, fluid mixing, active wetting, and droplet transport. Furthermore, because zero or even negative shear viscosities can be induced, vorticity can greatly extend the control range of the smart fluids used in magnetorheological devices. In recent work we have shown that a particular class of ac/ac/dc triaxial fields (so-called symmetry-breaking rational fields) can create strong vorticity in magnetic particle suspensions and have presented a theory of the vorticity that is based on the symmetry of the 2-d Lissajous trajectories of the field and its converse. In this paper we demonstrate that there are three countably infinite sets of fully alternating ac/ac/ac triaxial fields whose frequencies form rational triads that have the symmetry required to drive fluid vorticity. The symmetry of the 3-d Lissajous trajectories of the field and its converse can be derived and from this the direction of the vorticity axis can be predicted, as can the dependence of the sign of the vorticity on the phase relations between the three field components. Experimental results are presented that validate the symmetry theory. These discoveries significantly broaden the class of triaxial fields that can be exploited to produce strong noncontact flow.

  17. Ectopic expression of Capsicum-specific cell wall protein Capsicum annuum senescence-delaying 1 (CaSD1) delays senescence and induces trichome formation in Nicotiana benthamiana.

    PubMed

    Seo, Eunyoung; Yeom, Seon-In; Jo, Sunghwan; Jeong, Heejin; Kang, Byoung-Cheorl; Choi, Doil

    2012-04-01

    Secreted proteins are known to have multiple roles in plant development, metabolism, and stress response. In a previous study to understand the roles of secreted proteins, Capsicum annuum secreted proteins (CaS) were isolated by yeast secretion trap. Among the secreted proteins, we further characterized Capsicum annuum senescence-delaying 1 (CaSD1), a gene encoding a novel secreted protein that is present only in the genus Capsicum. The deduced CaSD1 contains multiple repeats of the amino acid sequence KPPIHNHKPTDYDRS. Interestingly, the number of repeats varied among cultivars and species in the Capsicum genus. CaSD1 is constitutively expressed in roots, and Agrobacterium-mediated transient overexpression of CaSD1 in Nicotiana benthamiana leaves resulted in delayed senescence with a dramatically increased number of trichomes and enlarged epidermal cells. Furthermore, senescence- and cell division-related genes were differentially regulated by CaSD1-overexpressing plants. These observations imply that the pepper-specific cell wall protein CaSD1 plays roles in plant growth and development by regulating cell division and differentiation.

  18. Modeling of Failure for Analysis of Triaxial Braided Carbon Fiber Composites

    NASA Technical Reports Server (NTRS)

    Goldberg, Robert K.; Littell, Justin D.; Binienda, Wieslaw K.

    2010-01-01

    In the development of advanced aircraft-engine fan cases and containment systems, composite materials are beginning to be used due to their low weight and high strength. The design of these structures must include the capability of withstanding impact loads from a released fan blade. Relatively complex triaxially braided fiber architectures have been found to yield the best performance for the fan cases. To properly work with and design these structures, robust analytical tools are required that can be used in the design process. A new analytical approach models triaxially braided carbon fiber composite materials within the environment of a transient dynamic finite-element code, specifically the commercially available transient dynamic finite-element code LS-DYNA. The geometry of the braided composites is approximated by a series of parallel laminated composites. The composite is modeled by using shell finite elements. The material property data are computed by examining test data from static tests on braided composites, where optical strain measurement techniques are used to examine the local strain variations within the material. These local strain data from the braided composite tests are used along with a judicious application of composite micromechanics- based methods to compute the stiffness properties of an equivalent unidirectional laminated composite required for the shell elements. The local strain data from the braided composite tests are also applied to back out strength and failure properties of the equivalent unidirectional composite. The properties utilized are geared towards the application of a continuum damage mechanics-based composite constitutive model available within LS-DYNA. The developed model can be applied to conduct impact simulations of structures composed of triaxially braided composites. The advantage of this technology is that it facilitates the analysis of the deformation and damage response of a triaxially braided polymer matrix

  19. Influence of dynamical equatorial flattening and orientation of a triaxial core on prograde diurnal polar motion

    NASA Astrophysics Data System (ADS)

    Sun, Rong; Shen, WenBin

    2016-04-01

    The noise floor of empirical models of diurnal Earth Rotation could reach as low as 1μas as shown by several recent studies. In another aspect, the differences between these empirical models with the theoretical model predictions given by IERS Convention (2010) for certain diurnal frequencies are more than 10 μas (e.g. K1). The traxiality of the core is ignored in the theoretical model given by IERS Convention (2010) because it is highly uncertain. To explain the difference between the empirical model and theoretical model, we consider the possible influence of a triaxial core. We use the difference between empirical models and theoretical model predictions given by IERS Convention (2010) as input to invert the traxiality parameter of the core. In the inversion, we assume the ocean tide response obeys the admittance theory. So extra six admittance parameters are introduced to model the difference between smooth responses inferred from empirical models and that given by theoretical model predictions from IERS Convention (2010). The results show that adding core triaxiality into the theoretical model could narrow the difference between empirical model and theoretical model at diurnal frequencies. The residual of amplitude becomes smaller. For a set of tide components consisting of seven diurnal frequencies (Q1, O1, M1, P1, K1, J1, Oo1), the root mean square of the residual of this set have decreased from more than 10μas to 2˜3μas for most of the empirical models. As for the dynamical equatorial flattening of the core, estimates inverted based on different empirical models are consistent within standard deviation. The results also suggest that the principal axes of the triaxial core does not coincidence with the principal axes of the whole Earth. This study is supported by National 973 Project China (grant No. 2013CB733305), NSFC (grant Nos. 41174011, 41210006, 41504019).

  20. A Study of Soil Dynamic Behaviors Over Large Scale Strians During Unconsolidated-Undrained Triaxial Testing

    NASA Astrophysics Data System (ADS)

    Lu, Z.

    2002-12-01

    In this study, a conventional triaxial cell was modified to measure the compressional wave velocity during a triaxial test. Two air-dry remolded soil samples, taken from the counties of Sharkey and Neshoba, MS respectively, were chosen for the study. Unconsolidated-undrained triaxial tests (UU tests) with pore pressure measurement were carried out under different confining pressures. Soils were compressed axially with axial strain levels up to 22% and subjected to unload - reload stress path cycles before and after soil failure. The velocities of the compressional wave in the axial direction as a function of the axial strain were measured along with the measurement of the stress-strain response. The dynamic behavior of soils versus the effective stress during the isotropic loading, normally consolidated compression and unload-reload stress path cycles were examined. It is found that the acoustic velocity and the deviator stress behave similarly. The linear increments in both the acoustic velocity and the deviator stress are observed in the early stage of compression. The rates of increment of these two parameters decrease at mediate axial strains, which reveals the nonlinear behavior of soil. The acoustic velocity and the deviator stress exhibit maximums when the soils were sheared to failure and they change slowly after failure. During unload-reload cycle tests, the acoustic velocity and the deviator stress vary steeply and present the load-history dependent properties. The compressional wave velocity increases linearly with the effective stresses under the isotropic loading and normal consolidation compression phases. The relationship between the acoustic velocity and the effective stress displays complex hysteresis phenomena during unload-reload stress path cycles.

  1. Uniaxial and triaxial compression tests of silicon carbide ceramics under quasi-static loading condition.

    SciTech Connect

    Brannon, Rebecca Moss; Lee, Moo Yul; Bronowski, David R.

    2005-02-01

    To establish mechanical properties and failure criteria of silicon carbide (SiC-N) ceramics, a series of quasi-static compression tests has been completed using a high-pressure vessel and a unique sample alignment jig. This report summarizes the test methods, set-up, relevant observations, and results from the constitutive experimental efforts. Results from the uniaxial and triaxial compression tests established the failure threshold for the SiC-N ceramics in terms of stress invariants (I{sub 1} and J{sub 2}) over the range 1246 < I{sub 1} < 2405. In this range, results are fitted to the following limit function (Fossum and Brannon, 2004) {radical}J{sub 2}(MPa) = a{sub 1} - a{sub 3}e -a{sub 2}(I{sub 1}/3) + a{sub 4} I{sub 1}/3, where a{sub 1} = 10181 MPa, a{sub 2} = 4.2 x 10{sup -4}, a{sub 3} = 11372 MPa, and a{sub 4} = 1.046. Combining these quasistatic triaxial compression strength measurements with existing data at higher pressures naturally results in different values for the least-squares fit to this function, appropriate over a broader pressure range. These triaxial compression tests are significant because they constitute the first successful measurements of SiC-N compressive strength under quasistatic conditions. Having an unconfined compressive strength of {approx}3800 MPa, SiC-N has been heretofore tested only under dynamic conditions to achieve a sufficiently large load to induce failure. Obtaining reliable quasi-static strength measurements has required design of a special alignment jig and load-spreader assembly, as well as redundant gages to ensure alignment. When considered in combination with existing dynamic strength measurements, these data significantly advance the characterization of pressure-dependence of strength, which is important for penetration simulations where failed regions are often at lower pressures than intact regions.

  2. Interband B (E2) ratios in the rigid triaxial model, a review

    NASA Astrophysics Data System (ADS)

    Gupta, J. B.; Sharma, S.

    1989-01-01

    Uptodate accurate extensive data on γ-g B(E2) ratios for even-even rare-earth nuclei is compared with the predictions of the rigid triaxial model of collective rotation to search for a correlation between the nuclear structure variation with Z, N and the γ0 parameter of the model. The internal consistency in the predictions of the model is investigated and the spectral features vis-a-vis the γ-soft and the γ-rigid potential are discussed.

  3. Triaxial strongly deformed bands in {sup 164}Hf and the effect of elevated yrast line

    SciTech Connect

    Ma Wenchao

    2012-10-20

    Two exotic rotational bands have been identified in {sup 164}Hf and linked to known states. They are interpreted as being associated with the calculated triaxial strongly deformed (TSD) potential energy minimum. The bands are substantially stronger and are located at much lower spins than the previously discovered TSD bands in {sup 168}Hf. In addition to the proton and neutron shell gaps at large trixiality, it was proposed that the relative excitation energy of TSD bands above the yrast line plays an important role in the population of TSD bands.

  4. A low-power fall detection algorithm based on triaxial acceleration and barometric pressure.

    PubMed

    Wang, Changhong; Narayanan, Michael R; Lord, Stephen R; Redmond, Stephen J; Lovell, Nigel H

    2014-01-01

    This paper proposes a low-power fall detection algorithm based on triaxial accelerometry and barometric pressure signals. The algorithm dynamically adjusts the sampling rate of an accelerometer and manages data transmission between sensors and a controller to reduce power consumption. The results of simulation show that the sensitivity and specificity of the proposed fall detection algorithm are both above 96% when applied to a previously collected dataset comprising 20 young actors performing a combination of simulated falls and activities of daily living. This level of performance can be achieved despite a 10.9% reduction in power consumption.

  5. Galactic spiral pattern beyond the optical size induced by the triaxial dark halo

    NASA Astrophysics Data System (ADS)

    Butenko, M.; Khoperskov, A.; Khoperskov, S.

    We suggest a possible mechanism for the formation of non-tidal gaseous structures in galactic outskirts. According to recent observations, extended spiral structures are detected beyond the optical radii Ropt in numerous disk galaxies. Such features can be clearly seen in deep HI and UV images (e.g., NGC 3198, NGC 3359, NGC 2841, NGC 3198). We argue, based on our gas-dynamical simulations, that such outer spirals could form as a result of the interaction of the galactic disk with the triaxial host dark matter halo.

  6. Level set discrete element method for three-dimensional computations with triaxial case study

    NASA Astrophysics Data System (ADS)

    Kawamoto, Reid; Andò, Edward; Viggiani, Gioacchino; Andrade, José E.

    2016-06-01

    In this paper, we outline the level set discrete element method (LS-DEM) which is a discrete element method variant able to simulate systems of particles with arbitrary shape using level set functions as a geometric basis. This unique formulation allows seamless interfacing with level set-based characterization methods as well as computational ease in contact calculations. We then apply LS-DEM to simulate two virtual triaxial specimens generated from XRCT images of experiments and demonstrate LS-DEM's ability to quantitatively capture and predict stress-strain and volume-strain behavior observed in the experiments.

  7. Chiral geometry of higher excited bands in triaxial nuclei with particle-hole configuration

    NASA Astrophysics Data System (ADS)

    Chen, Q. B.; Yao, J. M.; Zhang, S. Q.; Qi, B.

    2010-12-01

    The lowest six rotational bands have been studied in the particle-rotor model with the particle-hole configuration πh11/21⊗νh11/2-1 and different values of the triaxiality parameter γ. Both constant and spin-dependent variable moments of inertia (CMI and VMI, respectively) are introduced. The energy spectra, electromagnetic transition probabilities, angular momentum components, and K distribution are examined. It is shown that, besides bands 1 and 2, the predicted bands 3 and 4 in the calculations with both CMI and VMI for atomic nuclei with γ=30° could be interpreted as chiral doublet bands.

  8. Selection rules for electromagnetic transitions in triaxially deformed odd-A nuclei

    SciTech Connect

    Tanabe, Kosai; Sugawara-Tanabe, Kazuko

    2008-06-15

    The approximate selection rules for the interband and intraband electromagnetic transitions are predicted referring to two quantum numbers, which are derived from an algebraic solution for the particle-rotor model with one high-j nucleon coupled to a triaxially deformed core. It is shown that the inclusion of angular momentum dependence for moments of inertia reproduces the experimental excitation energies relative to a reference quite well both for positive and negative parity TSD bands in {sup 161,163,165,167}Lu.

  9. A low-power fall detection algorithm based on triaxial acceleration and barometric pressure.

    PubMed

    Wang, Changhong; Narayanan, Michael R; Lord, Stephen R; Redmond, Stephen J; Lovell, Nigel H

    2014-01-01

    This paper proposes a low-power fall detection algorithm based on triaxial accelerometry and barometric pressure signals. The algorithm dynamically adjusts the sampling rate of an accelerometer and manages data transmission between sensors and a controller to reduce power consumption. The results of simulation show that the sensitivity and specificity of the proposed fall detection algorithm are both above 96% when applied to a previously collected dataset comprising 20 young actors performing a combination of simulated falls and activities of daily living. This level of performance can be achieved despite a 10.9% reduction in power consumption. PMID:25570023

  10. Multiple asteroid rendezvous missions

    NASA Technical Reports Server (NTRS)

    Bender, D. F.; Friedlander, A. L.

    1979-01-01

    Asteroid missions, centered on multiple asteroid rendezvous missions to main belt asteroids, are discussed and the required solar electric propulsion for these missions as well as the current performance estimates are examined. A brief statistical analysis involving asteroid availability transfer requirements and propulsion system capabilities is given, leading to a prediction that 5 to 8 asteroids can be encountered with a single launch. Measurement techniques include visual imaging, radio tracking, magnetometry, and in the case of landers, seismometry. The spacecraft will be propelled by a solar electric system with a power level of 25 kW to 40 kW and tour possibilities for 13 different asteroids have been developed. Preliminary estimates of asteroid triaxiality are made to calculate the effect of close orbits.

  11. An improved suppression method of the transverse-electromagnetic mode leakage with two reflectors in the triaxial klystron amplifier

    SciTech Connect

    Qi, Zumin; Zhang, Jun; Zhong, Huihuang; Zhang, Qiang; Zhu, Danni

    2014-07-15

    Suppression of the transverse-electromagnetic (TEM) mode leakage is crucial in the design of a triaxial klystron amplifier with high gain, because a small microwave leakage from the buncher or the output cavity could overwhelm the input signal with low power. In this paper, a specially designed reflector is proposed to suppress the TEM mode leakage, whose axial electric field is approximately zero at the beam radial position. Theoretical analysis indicates that the reflector introduces little influence on the normal modulation of the beam while keeping a high reflection coefficient. By using two such reflectors with different eigen frequencies located in front of the buncher cavity and the output cavity, respectively, an improved triaxial klystron amplifier is presented. The simulation results show that the reflectors substantially decrease the TEM mode leakage power and achieve very good isolation among the cavities. The improved triaxial klystron amplifier can operate normally with 10's kW microwave injection without self-oscillations.

  12. Combined triaxial accelerometry and heart rate telemetry for the physiological characterization of Latin dance in non-professional adults.

    PubMed

    Domene, Pablo A; Easton, Chris

    2014-03-01

    The purpose of this study was to value calibrate, cross-validate, and determine the reliability of a combined triaxial accelerometry and heart rate telemetry technique for characterizing the physiological and physical activity parameters of Latin dance. Twenty-two non-professional adult Latin dancers attended two laboratory-based dance trials each. After familiarization and a standardized warm-up, a multi-stage (3 x 5-minute) incremental (based on song tempo) Afro-Cuban salsa choreography was performed while following a video displayed on a projection screen. Data were collected with a portable indirect calorimeter, a heart rate telemeter, and wrist-, hip-, and ankle-mounted ActiGraph GT3X+ accelerometers. Prediction equations for energy expenditure and step count were value calibrated using forced entry multiple regression and cross-validated using a delete-one jackknife approach with additional Bland-Altman analysis. The average dance intensity reached 6.09 ± 0.96 kcal/kg/h and demanded 45.9 ± 11.3% of the heart rate reserve. Predictive ability of the derived models was satisfactory, where R(2) = 0.80; SEE = 0.44 kcal/kg/h and R(2) = 0.74; SEE = 3 step/min for energy expenditure and step count, respectively. Dependent t-tests indicated no differences between predicted and measured values for both energy expenditure (t65 = -0.25, p = 0.80) and step count (t65 = -0.89, p = 0.38). The 95% limits of agreement for energy expenditure and step count were -0.98 to 0.95 kcal/kg/h and -7 to 7 step/min, respectively. Latin dance to salsa music elicits physiological responses representative of moderate to vigorous physical activity, and a wrist-worn accelerometer with simultaneous heart rate measurement constitutes a valid and reliable technique for the prediction of energy expenditure and step count during Latin dance.

  13. Triaxial shapes in the ground states of even-even neutron-rich Ru isotopes

    SciTech Connect

    Ahmad, I.; Lister, C.J.; Morss, L.R.

    1995-08-01

    Partial level schemes for {sup 108,110,112}Ru, and {sup 114}Ru about which nothing was previously known, were determined from the measurement of prompt, triple-gamma coincidences in {sup 248}Cm fission fragments. A 5-mg {sup 249}Cm source, mixed with 65-mg KCl and pressed in the form of a 7-mm diameter pellet, was used for the experiment. Prompt {gamma} rays emitted from the fission fragments were detected with the Eurogam array at Daresbury, which at that time consisted of 45 Compton suppressed Ge detectors and 5 LEPS spectrometers. Transitions in Ru were identified by gating on {gamma} rays in the complementary Te fragments. Figure I-25 shows the technique used to identify the previously unknown transitions in {sup 114}Ru and its partial level scheme. High spin states up to spin 10 h were observed and the {gamma}-ray branching ratios were determined. The ratios of electric quadrupole transition probabilities deduced from the experimental branching ratios were found to be in good agreement with the predictions of a simple model of rigid triaxial rotor. Our analysis shows that gamma deformation in Ru isotopes is increasing with the neutron number and the gamma value for {sup 112}Ru and {sup 114}Ru is {approximately} 25 degrees. This is one of the highest gamma values encountered in nuclei, suggesting soft triaxial shapes for {sup 112}Ru and {sup 114}Ru. The results of this investigation were published.

  14. Multistep triaxial strength tests: Investigating strength parameters and pore pressure effects on Opalinus Clay

    NASA Astrophysics Data System (ADS)

    Gräsle, W.

    Natural variability between rock samples often hampers a detailed analysis of material properties. For the investigation of strength parameters the concept of multistep triaxial strength tests was developed to avoid the impact of sample variability. The limit of linear elastic behavior, shear strength and residual strength were measured at different confining pressure on a single specimen. Appropriate tools for near real time data analysis were developed to facilitate a precise and timely control of the test procedure. This is essential to minimize the problem of sample degradation during the test. The feasibility of the test concept was proven on three samples of Opalinus Clay from the Mont Terri rock laboratory. Each investigated strength parameter displayed a distinct deviation from a linear dependency on confining pressure or mean stress respectively. Instead, curves consisting of two linear branches almost perfectly fit the test results. These results could be explained in the framework of poroelastic theory. Although it is not possible to determine Skempton’s B-parameter ( Skempton, 1954) and the Biot-Willis poroelastic parameter ( Biot and Willis, 1957) separately from multistep strength tests, the product of both parameters can be derived from the test results. Although material anisotropy was found by the test results, numerous simple strength tests ( Gräsle and Plischke, 2010) as well as true triaxial tests ( Naumann et al., 2007) provide a more efficient way to investigate anisotropy.

  15. A Mode Matched Triaxial Vibratory Wheel Gyroscope with Fully Decoupled Structure.

    PubMed

    Xia, Dunzhu; Kong, Lun; Gao, Haiyu

    2015-11-17

    To avoid the oscillation of four unequal masses seen in previous triaxial linear gyroscopes, a modified silicon triaxial gyroscope with a rotary wheel is presented in this paper. To maintain a large sensitivity and suppress the coupling of different modes, this novel gyroscope structure is designed be perfectly symmetrical with a relatively large size of about 9.8 mm × 9.8 mm. It is available for differentially detecting three-axis angular rates simultaneously. To overcome the coupling between drive and sense modes, numerous necessary frames, beams, and anchors are delicately figured out and properly arranged. Besides, some frequency tuning and feedback mechanisms are addressed in the case of post processing after fabrication. To facilitate mode matched function, a new artificial fish swarm algorithm (AFSA) performed faster than particle swarm optimization (PSO) with a frequency split of 108 Hz. Then, by entrusting the post adjustment of the springs dimensions to the finite element method (FEM) software ANSYS, the final frequency splits can be below 3 Hz. The simulation results demonstrate that the modal frequencies in drive and different sense modes are respectively 8001.1, 8002.6, 8002.8 and 8003.3 Hz. Subsequently, different axis cross coupling effects and scale factors are also analyzed. The simulation results effectively validate the feasibility of the design and relevant theoretical calculation.

  16. Characterization and Analysis of Triaxially Braided Polymer Composites under Static and Impact Loads

    NASA Technical Reports Server (NTRS)

    Goldberg, Robert K.; Roberts, Gary D.; Blinzler, Brina J.; Kohlman, Lee W.; Binienda, Wieslaw K.

    2012-01-01

    In order to design impact resistant aerospace components made of triaxially-braided polymer matrix composite materials, a need exists to have reliable impact simulation methods and a detailed understanding of the material behavior. Traditional test methods and specimen designs have yielded unrealistic material property data due to material mechanisms such as edge damage. To overcome these deficiencies, various alternative testing geometries such as notched flat coupons have been examined to alleviate difficulties observed with standard test methods. The results from the coupon level tests have been used to characterize and validate a macro level finite element-based model which can be used to simulate the mechanical and impact response of the braided composites. In the analytical model, the triaxial braid unit cell is approximated by using four parallel laminated composites, each with a different fiber layup, which roughly simulates the braid architecture. In the analysis, each of these laminated composites is modeled as a shell element. Currently, each shell element is considered to be a smeared homogeneous material. Simplified micromechanics techniques and lamination theory are used to determine the equivalent stiffness properties of each shell element, and results from the coupon level tests on the braided composite are used to back out the strength properties of each shell element. Recent improvements to the model include the incorporation of strain rate effects into the model. Simulations of ballistic impact tests have been carried out to investigate and verify the analysis approach.

  17. Investigation of a Macromechanical Approach to Analyzing Triaxially-Braided Polymer Composites

    NASA Technical Reports Server (NTRS)

    Goldberg, Robert K.; Blinzler, Brina J.; Binienda, Wieslaw K.

    2010-01-01

    A macro level finite element-based model has been developed to simulate the mechanical and impact response of triaxially-braided polymer matrix composites. In the analytical model, the triaxial braid architecture is simulated by using four parallel shell elements, each of which is modeled as a laminated composite. The commercial transient dynamic finite element code LS-DYNA is used to conduct the simulations, and a continuum damage mechanics model internal to LS-DYNA is used as the material constitutive model. The material stiffness and strength values required for the constitutive model are determined based on coupon level tests on the braided composite. Simulations of quasi-static coupon tests of a representative braided composite are conducted. Varying the strength values that are input to the material model is found to have a significant influence on the effective material response predicted by the finite element analysis, sometimes in ways that at first glance appear non-intuitive. A parametric study involving the input strength parameters provides guidance on how the analysis model can be improved.

  18. Self-consistent models for triaxial galaxies with flat rotation curves - The disk case

    NASA Technical Reports Server (NTRS)

    Kuijken, Konrad

    1993-01-01

    We examine the possibility of constructing scale-free triaxial logarithmic potentials self-consistently, using Schwarzschild's linear programing method. In particular, we explore the limit of nonaxisymmetric disks. In this case it is possible to reduce the problem to the self-consistent reconstruction of the disk surface density on the unit circle, a considerably simpler problem than the usual 2D or 3D one. Models with surface densities of the form Sigma = (x exp n + (y/q) exp n) exp - 1/n with n = 2 or 4 are investigated. We show that the complicated shapes of the 'boxlet' orbit families (which replace the box orbit family found in potentials with smooth cores) limit the possibility of building self-consistent models, though elliptical disks of axis ratio above 0.7 and a restricted range of boxier models can be constructed. This result relies on using sufficiently fine bins, smaller than the 10 deg bins commonly used in 2D or 3D investigations. It also indicates the need for caution in interpreting N-body models of triaxial halos in which the core of the potential is numerically smoothed.

  19. A Mode Matched Triaxial Vibratory Wheel Gyroscope with Fully Decoupled Structure.

    PubMed

    Xia, Dunzhu; Kong, Lun; Gao, Haiyu

    2015-01-01

    To avoid the oscillation of four unequal masses seen in previous triaxial linear gyroscopes, a modified silicon triaxial gyroscope with a rotary wheel is presented in this paper. To maintain a large sensitivity and suppress the coupling of different modes, this novel gyroscope structure is designed be perfectly symmetrical with a relatively large size of about 9.8 mm × 9.8 mm. It is available for differentially detecting three-axis angular rates simultaneously. To overcome the coupling between drive and sense modes, numerous necessary frames, beams, and anchors are delicately figured out and properly arranged. Besides, some frequency tuning and feedback mechanisms are addressed in the case of post processing after fabrication. To facilitate mode matched function, a new artificial fish swarm algorithm (AFSA) performed faster than particle swarm optimization (PSO) with a frequency split of 108 Hz. Then, by entrusting the post adjustment of the springs dimensions to the finite element method (FEM) software ANSYS, the final frequency splits can be below 3 Hz. The simulation results demonstrate that the modal frequencies in drive and different sense modes are respectively 8001.1, 8002.6, 8002.8 and 8003.3 Hz. Subsequently, different axis cross coupling effects and scale factors are also analyzed. The simulation results effectively validate the feasibility of the design and relevant theoretical calculation. PMID:26593916

  20. Effective detection method for falls according to the distance between two tri-axial accelerometers

    NASA Astrophysics Data System (ADS)

    Kim, Jae-Hyung; Park, Geun-Chul; Kim, Soo-Hong; Kim, Soo-Sung; Lee, Hae-Rim; Jeon, Gye-Rok

    2016-04-01

    Falls and fall-related injuries are a significant problem in the elderly population. A number of different approaches for detecting falls and activities of daily living (ADLs) have been conducted in recent years. However, distinguishing between real falls and certain fall-like ADL is often difficult. The aim of this study is to discriminate falls from fall-like ADLs such as jogging, jumping, and jumping down. The distance between two tri-axial accelerometers attached to the abdomen and the sternum was increased from 10 to 30 cm in 10-cm intervals. Experiments for falls and ADLs were performed to investigate the feasibility of the detection system for falls developed in this study. When the distances between the two tri-axial electrometers were 20 and 30 cm, fall-like ADLs were effectively distinguished from falls. The thresholds for three parameters — SVM, Diff Z, and Sum_diff_Z — were set; falls could be distinguished from ADL action sequences when the SVM value was larger than 4 g (TH1), the Diff_Z parameter was larger than 1.25 g (TH2), and the Sum_diff_Z parameter was larger than 15 m/s (TH3). In particular, when the SVM, Diff_Z, and Sum_diff_Z parameter were sequentially applied to thresholds (TH1, TH2, and TH3), fall-like ADL action sequences were accurately discriminated from falls.

  1. Attenuation Properties of Fontainebleau Sandstone During True-Triaxial Deformation using Active and Passive Ultrasonics

    NASA Astrophysics Data System (ADS)

    Goodfellow, S. D.; Tisato, N.; Ghofranitabari, M.; Nasseri, M. H. B.; Young, R. P.

    2015-11-01

    Active and passive ultrasonic methods were used to study the evolution of attenuation properties in a sample of Fontainebleau sandstone during true-triaxial deformation. A cubic sample of Fontainebleau sandstone (80 mm × 80 mm × 80 mm) was deformed under true-triaxial stresses until failure. From the stress state: σ _3 = 5 MPa and σ _1 = σ _2 = 35 MPa, σ _1 was increased at a constant displacement rate until the specimen failed. Acoustic emission (AE) activity was monitored by 18 piezoelectric sensors and bandpass filtered between 100 kHz and 1 MHz. A source location analysis was performed on discrete AE data harvested from the continuous record where 48,502 events were locatable inside the sample volume. AE sensors were sequentially pulsed during periodic P-wave surveys among 135 raypaths. Analytical solutions for Biot, squirt flow, viscous shear, and scattering attenuation were used to discuss to observed attenuation at various stages of the experiment. We concluded that initial attenuation anisotropy was stress induced and resulted from friction and squirt flow. Later attenuation of the high-frequency spectrum was attributed to scattering as a result of the formation of large macroscopic vertical fractures. Passive (AE) ultrasonic data produced similar information to that from active data but with enhanced temporal and spacial resolution.

  2. A Mode Matched Triaxial Vibratory Wheel Gyroscope with Fully Decoupled Structure

    PubMed Central

    Xia, Dunzhu; Kong, Lun; Gao, Haiyu

    2015-01-01

    To avoid the oscillation of four unequal masses seen in previous triaxial linear gyroscopes, a modified silicon triaxial gyroscope with a rotary wheel is presented in this paper. To maintain a large sensitivity and suppress the coupling of different modes, this novel gyroscope structure is designed be perfectly symmetrical with a relatively large size of about 9.8 mm × 9.8 mm. It is available for differentially detecting three-axis angular rates simultaneously. To overcome the coupling between drive and sense modes, numerous necessary frames, beams, and anchors are delicately figured out and properly arranged. Besides, some frequency tuning and feedback mechanisms are addressed in the case of post processing after fabrication. To facilitate mode matched function, a new artificial fish swarm algorithm (AFSA) performed faster than particle swarm optimization (PSO) with a frequency split of 108 Hz. Then, by entrusting the post adjustment of the springs dimensions to the finite element method (FEM) software ANSYS, the final frequency splits can be below 3 Hz. The simulation results demonstrate that the modal frequencies in drive and different sense modes are respectively 8001.1, 8002.6, 8002.8 and 8003.3 Hz. Subsequently, different axis cross coupling effects and scale factors are also analyzed. The simulation results effectively validate the feasibility of the design and relevant theoretical calculation. PMID:26593916

  3. Experimental and Numerical Analysis of Triaxially Braided Composites Utilizing a Modified Subcell Modeling Approach

    NASA Technical Reports Server (NTRS)

    Cater, Christopher; Xiao, Xinran; Goldberg, Robert K.; Kohlman, Lee W.

    2015-01-01

    A combined experimental and analytical approach was performed for characterizing and modeling triaxially braided composites with a modified subcell modeling strategy. Tensile coupon tests were conducted on a [0deg/60deg/-60deg] braided composite at angles of 0deg, 30deg, 45deg, 60deg and 90deg relative to the axial tow of the braid. It was found that measured coupon strength varied significantly with the angle of the applied load and each coupon direction exhibited unique final failures. The subcell modeling approach implemented into the finite element software LS-DYNA was used to simulate the various tensile coupon test angles. The modeling approach was successful in predicting both the coupon strength and reported failure mode for the 0deg, 30deg and 60deg loading directions. The model over-predicted the strength in the 90deg direction; however, the experimental results show a strong influence of free edge effects on damage initiation and failure. In the absence of these local free edge effects, the subcell modeling approach showed promise as a viable and computationally efficient analysis tool for triaxially braided composite structures. Future work will focus on validation of the approach for predicting the impact response of the braided composite against flat panel impact tests.

  4. In situ triaxial magnetic field compensation for the spin-exchange-relaxation-free atomic magnetometer.

    PubMed

    Fang, Jiancheng; Qin, Jie

    2012-10-01

    The spin-exchange-relaxation-free (SERF) atomic magnetometer is an ultra-high sensitivity magnetometer, but it must be operated in a magnetic field with strength less than about 10 nT. Magnetic field compensation is an effective way to shield the magnetic field, and this paper demonstrates an in situ triaxial magnetic field compensation system for operating the SERF atomic magnetometer. The proposed hardware is based on optical pumping, which uses some part of the SERF atomic magnetometer itself, and the compensation method is implemented by analyzing the dynamics of the atomic spin. The experimental setup for this compensation system is described, and with this configuration, a residual magnetic field of strength less than 2 nT (±0.38 nT in the x axis, ±0.43 nT in the y axis, and ±1.62 nT in the z axis) has been achieved after compensation. The SERF atomic magnetometer was then used to verify that the residual triaxial magnetic fields were coincident with what were achieved by the compensation system.

  5. Phase space dynamics of triaxial collapse: joint density-velocity evolution

    NASA Astrophysics Data System (ADS)

    Nadkarni-Ghosh, Sharvari; Singhal, Akshat

    2016-04-01

    We investigate the dynamics of triaxial collapse in terms of eigenvalues of the deformation tensor, the velocity derivative tensor and the gravity Hessian. Using the Bond-Myers model of ellipsoidal collapse, we derive a new set of equations for the nine eigenvalues and examine their dynamics in phase space. The main advantage of this form is that it eliminates the complicated elliptic integrals that appear in the axes evolution equations and is more natural way to understand the interplay between the perturbations. This paper focuses on the density-velocity dynamics. The Zeldovich approximation implies that the three tensors are proportional; the proportionality constant is set by demanding `no decaying modes'. We extend this condition into the non-linear regime and find that the eigenvalues of the gravity Hessian and the velocity derivative tensor are related as {tilde{q}}_d + {tilde{q}}_v=1, where the triaxiality parameter {tilde{q}} = (λ _{max} - λ _{inter})/(λ _{max} - λ _{min}). This is a new universal relation holding true over all redshifts and a range of mass scales to within a few per cent accuracy. The mean density-velocity divergence relation at late times is close to linear, indicating that the dynamics is dictated by collapse along the largest eigendirection. This relation has a scatter, which we show is intimately connected to the velocity shear. Finally, as an application, we compute the PDFs of the two variables and compare with other forms in the literature.

  6. Tension Strength, Failure Prediction and Damage Mechanisms in 2D Triaxial Braided Composites with Notch

    NASA Technical Reports Server (NTRS)

    Norman, Timothy L.; Anglin, Colin

    1995-01-01

    The unnotched and notched (open hole) tensile strength and failure mechanisms of two-dimensional (2D) triaxial braided composites were examined. The effect of notch size and notch position were investigated. Damage initiation and propagation in notched and unnotched coupons were also examined. Theory developed to predict the normal stress distribution near an open hole and failure for tape laminated composites was evaluated for its applicability to 2D triaxial braided textile composite materials. Four different fiber architectures were considered; braid angle, yarn and braider size, percentage of longitudinal yarns and braider angle varied. Tape laminates equivalent to textile composites were also constructed for comparison. Unnotched tape equivalents were stronger than braided textiles but exhibited greater notch sensitivity. Notched textiles and tape equivalents have roughly the same strength at large notch sizes. Two common damage mechanisms were found: braider yarn cracking and near notch longitudinal yarn splitting. Cracking was found to initiate in braider yarns in unnotched and notched coupons, and propagate in the direction of the braider yarns until failure. Damage initiation stress decreased with increasing braid angle. No significant differences in prediction of near notch strain between textile and tape equivalents could be detected for small braid angle, but the correlations were weak for textiles with large braid angle. Notch strength could not be predicted using existing anisotropic theory for braided textiles due to their insensitivity to notch.

  7. On the origin of vorticity in magnetic particle suspensions subjected to triaxial fields.

    PubMed

    Martin, James E

    2016-07-01

    We have recently reported that two classes of time-dependent triaxial magnetic fields can induce vorticity in magnetic particle suspensions. The first class - symmetry-breaking fields - is comprised of two ac components and one dc component. The second class - rational triad fields - is comprised of three ac components. In both cases deterministic vorticity occurs when the ratios of the field frequencies form rational numbers. A strange aspect of these fields is that they produce fluid vorticity without generally having a circulating field vector, such as would occur in a rotating field. It has been shown, however, that the symmetry of the field trajectory, considered jointly with that of the converse field, allows vorticity to occur around one particular field axis. This axis might be any of the field components, and is determined by the relative frequencies of the field components. However, the symmetry theories give absolutely no insight into why vorticity should occur. In this paper we propose a particle-based model of vorticity in these driven fluids. This model proposes that particles form volatile chains that follow, but lag behind, the dynamic field vector. This model is consistent with the predictions of symmetry theory and gives reasonable agreement with previously reported torque density measurements for a variety of triaxial fields. PMID:27263641

  8. On the origin of vorticity in magnetic particle suspensions subjected to triaxial fields

    DOE PAGESBeta

    Martin, James E.

    2016-06-06

    We have recently reported that two classes of time-dependent triaxial magnetic fields can induce vorticity in magnetic particle suspensions. The first class – symmetry-breaking fields – is comprised of two ac components and one dc component. The second class – rational triad fields – is comprised of three ac components. In both cases deterministic vorticity occurs when the ratios of the field frequencies form rational numbers. A strange aspect of these fields is that they produce fluid vorticity without generally having a circulating field vector, such as would occur in a rotating field. It has been shown, however, that themore » symmetry of the field trajectory, considered jointly with that of the converse field, allows vorticity to occur around one particular field axis. This axis might be any of the field components, and is determined by the relative frequencies of the field components. However, the symmetry theories give absolutely no insight into why vorticity should occur. In this paper we propose a particle-based model of vorticity in these driven fluids. This model proposes that particles form volatile chains that follow, but lag behind, the dynamic field vector. Furthermore, this model is consistent with the predictions of symmetry theory and gives reasonable agreement with previously reported torque density measurements for a variety of triaxial fields.« less

  9. A Modeling Technique and Representation of Failure in the Analysis of Triaxial Braided Carbon Fiber Composites

    NASA Technical Reports Server (NTRS)

    Littell, Justin D.; Binienda, Wieslaw K.; Goldberg, Robert K.; Roberts, Gary D.

    2008-01-01

    Quasi-static tests have been performed on triaxially braided carbon fiber composite materials with large unit cell sizes. The effects of different fibers and matrix materials on the failure mode were investigated. Simulations of the tests have been performed using the transient dynamic finite element code, LS-DYNA. However, the wide range of failure modes observed for the triaxial braided carbon fiber composites during tests could not be simulated using composite material models currently available within LS-DYNA. A macroscopic approach has been developed that provides better simulation of the material response in these materials. This approach uses full-field optical measurement techniques to measure local failures during quasi-static testing. Information from these experiments is then used along with the current material models available in LS-DYNA to simulate the influence of the braided architecture on the failure process. This method uses two-dimensional shell elements with integration points through the thickness of the elements to represent the different layers of braid along with a new analytical method for the import of material stiffness and failure data directly. The present method is being used to examine the effect of material properties on the failure process. The experimental approaches used to obtain the required data will be described, and preliminary results of the numerical analysis will be presented.

  10. Activity classification using a single chest mounted tri-axial accelerometer.

    PubMed

    Godfrey, A; Bourke, A K; Olaighin, G M; van de Ven, P; Nelson, J

    2011-11-01

    Accelerometer-based activity monitoring sensors have become the most suitable means for objective assessment of mobility trends within patient study groups. The use of minimal, low power, IC (integrated circuit) components within these sensors enable continuous (long-term) monitoring which provides more accurate mobility trends (over days or weeks), reduced cost, longer battery life, reduced size and weight of sensor. Using scripted activities of daily living (ADL) such as sitting, standing, walking, and numerous postural transitions performed under supervised conditions by young and elderly subjects, the ability to discriminate these ADL were investigated using a single tri-axial accelerometer, mounted on the trunk. Data analysis was performed using Matlab® to determine the accelerations performed during eight different ADL. Transitions and transition types were detected using the scalar (dot) product technique and vertical velocity estimates on a single tri-axial accelerometer was compared to a proven discrete wavelet transform method that incorporated accelerometers and gyroscopes. Activities and postural transitions were accurately detected by this simplified low-power kinematic sensor and activity detection algorithm with a sensitivity and specificity of 86-92% for young healthy subjects in a controlled setting and 83-89% for elderly healthy subjects in a home environment. PMID:21636308

  11. Experimental and Numerical Analysis of Triaxially Braided Composites Utilizing a Modified Subcell Modeling Approach

    NASA Technical Reports Server (NTRS)

    Cater, Christopher; Xiao, Xinran; Goldberg, Robert K.; Kohlman, Lee W.

    2015-01-01

    A combined experimental and analytical approach was performed for characterizing and modeling triaxially braided composites with a modified subcell modeling strategy. Tensile coupon tests were conducted on a [0deg/60deg/-60deg] braided composite at angles [0deg, 30deg, 45deg, 60deg and 90deg] relative to the axial tow of the braid. It was found that measured coupon strength varied significantly with the angle of the applied load and each coupon direction exhibited unique final failures. The subcell modeling approach implemented into the finite element software LS-DYNA was used to simulate the various tensile coupon test angles. The modeling approach was successful in predicting both the coupon strength and reported failure mode for the 0deg, 30deg and 60deg loading directions. The model over-predicted the strength in the 90deg direction; however, the experimental results show a strong influence of free edge effects on damage initiation and failure. In the absence of these local free edge effects, the subcell modeling approach showed promise as a viable and computationally efficient analysis tool for triaxially braided composite structures. Future work will focus on validation of the approach for predicting the impact response of the braided composite against flat panel impact tests.

  12. Elastic-plastic deformations of a beam with the SD-effect

    SciTech Connect

    Pavilaynen, Galina V.

    2015-03-10

    The results for the bending of a cantilever beam with the SD-effect under a concentrated load are discussed. To solve this problem, the standard Bernoulli-Euler hypotheses for beams and the Ilyushin model of perfect plasticity are used. The problem is solved analytically for structural steel A40X. The SD-effect for elastic-plastic deformations is studied. The solutions for beam made of isotropic material and material with the SD-effect are compared.

  13. From dilatancy to contraction: Stress-dependent failure mode progression in two porous sandstones subjected to true triaxial testing

    NASA Astrophysics Data System (ADS)

    Ma, Xiaodong; Haimson, Bezalel

    2013-04-01

    Porous sedimentary rocks such as sandstones are typical oil-bearing formations in which failure due to high stress concentration is likely to occur during wellbore drilling and subsequent operations. The objective of this research was to investigate the effect of ?2 on strength, failure-plane angle, and failure mode under realistically simulated field conditions (?1 ×?2 ×?3). A series of true triaxial compression tests were conducted on two representative porous sandstones: Coconino (17.5% porosity, 99% quartz, with rounded and well-sorted 0.1 mm grains that are bonded by suturing and some quartz overgrowth), and Bentheim (24% porosity, 95% quartz, with sub-rounded 0.3 mm grains that are bonded exclusively by suturing). Square cuboidal specimens (19 x 19 x 38mm) were subjected to independent loads in three principal directions, using the University of Wisconsin testing apparatus, creating a true triaxial state of stress (?1 ×?2 ×?3). In all tests, ?3 and ?2 were maintained constant at predetermined levels, while ?1 was raised monotonically until failure occurred. The magnitude of ?3 varied between 0 and 150 MPa, covering the range of brittle behavior, brittle-ductile transition, and the threshold to the ductile zone in the weaker Bentheim sandstone. It was found that in both rocks the compressive strength (?1,peak) for a given ?3 increases as the preset ?2 is raised between tests, and reaches a peak (15% over ?1,peak when ?2 = ?3 in the Coconino, and less than 10% in the Bentheim), beyond which it gradually drops, such that when ?2 ? ?1,peak, the strength is approximately the same as when ?2 = ?3. This strengthening effect is considerably lower than that in previously tested crystalline rocks, such as Westerly granite and KTB amphibolite (more than 50%, Haimson, 2006). Plotting the test data in the ?oct vs. ?oct domain, where the two stress invariants ?oct, the octahedral shear stress, and ?oct,the mean normal stress, are both taken at failure), Coconino shows

  14. Case study of preliminary cyclic load evaluation and triaxial soil testing in offshore wind farm planning

    NASA Astrophysics Data System (ADS)

    Otto, Daniel; Ossig, Benjamin; Kreiter, Stefan; Kouery, Saed; Moerz, Tobias

    2010-05-01

    In 2020 Germany aims to produce 20% of its electrical power trough renewable energy sources. Assigned Offshore Wind farms in the German exclusive economic zone of the North- and the Baltic Sea are important step toward a fulfilment of this goal. However the save erecting of 5-6 MW wind power plants (total construction size: > 200m) in water depth of around 40 m is related to unprecedented technical, logistical and financial challenges. With an intended lifetime expectation of 50 years for the foundations, construction materials and the soils around the foundation are subject to high and continued stresses from self-weight, waves, wind and current. These stresses are not only static, but have also a significant cyclic component. An estimated 250 million cyclic load changes may lead to an accumulation of plastic deformation in the soil that potentially may affect operability or lifespan of the plant. During a preliminary geotechnical site survey of one of the largest (~150 km2) offshore wind project sites within the German Bight (~45 km North off the island Juist) a total of 16 drill cores with in situ cone penetration data and a total sample length of ~800 m where recovered. Preliminary foundation designs and static self weight and lateral load calculations were used to design a cycling triaxial lab testing program on discrete natural soil samples. Individual tests were performed by foundation type and at vertical and lateral load maxima to evaluate the long-term soil behaviour under cyclic load. Tests have been performed on granular, cohesive and intermediate natural soils. Following an introduction to the unique MARUM triaxial apparatus and testing conditions, the cyclic triaxial test results are shown and explained. Furthermore cyclic shear strength and stiffness are compared to their static counterparts. Unique soil behaviour like abrupt partial failure, pore pressure response and unexpected in part load independent cyclic deformation behaviour is discussed and

  15. Effect of Anisotropic Velocity Structure on Acoustic Emission Source Location during True-Triaxial Deformation Experiments

    NASA Astrophysics Data System (ADS)

    Ghofrani Tabari, Mehdi; Goodfellow, Sebastian; Young, R. Paul

    2016-04-01

    Although true-triaxial testing (TTT) of rocks is now more extensive worldwide, stress-induced heterogeneity due to the existence of several loading boundary effects is not usually accounted for and simplified anisotropic models are used. This study focuses on the enhanced anisotropic velocity structure to improve acoustic emission (AE) analysis for an enhanced interpretation of induced fracturing. Data from a TTT on a cubic sample of Fontainebleau sandstone is used in this study to evaluate the methodology. At different stages of the experiment the True-Triaxial Geophysical Imaging Cell (TTGIC), armed with an ultrasonic and AE monitoring system, performed several velocity surveys to image velocity structure of the sample. Going beyond a hydrostatic stress state (poro-elastic phase), the rock sample went through a non-dilatational elastic phase, a dilatational non-damaging elasto-plastic phase containing initial AE activity and finally a dilatational and damaging elasto-plastic phase up to the failure point. The experiment was divided into these phases based on the information obtained from strain, velocity and AE streaming data. Analysis of the ultrasonic velocity survey data discovered that a homogeneous anisotropic core in the center of the sample is formed with ellipsoidal symmetry under the standard polyaxial setup. Location of the transducer shots were improved by implementation of different velocity models for the sample starting from isotropic and homogeneous models going toward anisotropic and heterogeneous models. The transducer shot locations showed a major improvement after the velocity model corrections had been applied especially at the final phase of the experiment. This location improvement validated our velocity model at the final phase of the experiment consisting lower-velocity zones bearing partially saturated fractures. The ellipsoidal anisotropic velocity model was also verified at the core of the cubic rock specimen by AE event location of

  16. Numerical Simulation of Rock Fracturing under Laboratory True-Triaxial Stress Conditions

    NASA Astrophysics Data System (ADS)

    Ghofrani Tabari, Mehdi; Hazzard, Jim; Young, R. Paul

    2016-04-01

    A True-triaxial test (TTT) also known as polyaxial test was carried out on saturated Fontainebleau sandstone to elevate our knowledge about the role of the intermediate principal stress on deformation, fracturing and failure patterns of the rock using acoustic emission (AE) monitoring. The induced AE activities were studied by location of the AE events and mapping them on the captured features in the post-mortem CT scan images of the failed sample. The time-lapse monitoring of the velocity structure and AE activity in the sample portrayed a deformational path which led to propagation of fractures and formation of failure patterns in the rock. Having these experimental results, we aimed at running a numerical model of our true-triaxial testing system using an Itasca software based on three-dimensional explicit finite-difference method called FLAC3D. The loads were applied at the end of each platen while the steel platens transferred the stress to the surface of the cubic specimen. In order to simulate the failure, randomly distributed strength demonstrated by Mohr-Columb failure criterion was implemented in the spatial elements of the model representing the random distribution of the micro-cracks. During the experiment, pseudo-boundary surfaces were formed along the minimum and intermediate principal stress axes in the rock due to non-uniform distribution of stress as a result of geometrical constraints including the corner effects and friction on the platen-rock surfaces. Both the real AE data as well as the numerical simulation verified that coalescence of micro-cracks mainly occurred around these pseudo-boundaries with highest stress gradients as well as highest velocity gradients in the rock specimen and formed curvi-planar fractures. The rock specimen strength and brittleness in the macro-scale was also obtained from the stress-strain curve which was consistent with the experimental laboratory measurements. Eventually, the failure of the rock specimen was

  17. Full-field Strain Methods for Investigating Failure Mechanisms in Triaxial Braided Composites

    NASA Technical Reports Server (NTRS)

    Littell, Justin D.; Binienda, Wieslaw K.; Goldberg, Robert K.; Roberts, Gary D.

    2008-01-01

    Composite materials made with triaxial braid architecture and large tow size carbon fibers are beginning to be used in many applications, including composite aircraft and engine structures. Recent advancements in braiding technology have led to commercially viable manufacturing approaches for making large structures with complex shape. Although the large unit cell size of these materials is an advantage for manufacturing efficiency, the fiber architecture presents some challenges for materials characterization, design, and analysis. In some cases, the static load capability of structures made using these materials has been higher than expected based on material strength properties measured using standard coupon tests. A potential problem with using standard tests methods for these materials is that the unit cell size can be an unacceptably large fraction of the specimen dimensions. More detailed investigation of deformation and failure processes in large unit cell size triaxial braid composites is needed to evaluate the applicability of standard test methods for these materials and to develop alternative testing approaches. In recent years, commercial equipment has become available that enables digital image correlation to be used on a more routine basis for investigation of full field 3D deformation in materials and structures. In this paper, some new techniques that have been developed to investigate local deformation and failure using digital image correlation techniques are presented. The methods were used to measure both local and global strains during standard straight-sided coupon tensile tests on composite materials made with 12 and 24 k yarns and a 0/+60/-60 triaxial braid architecture. Local deformation and failure within fiber bundles was observed, and this local failure had a significant effect on global stiffness and strength. The matrix material had a large effect on local damage initiation for the two matrix materials used in this investigation

  18. Genetics Home Reference: multiple system atrophy

    MedlinePlus

    ... OPCA progressive autonomic failure with multiple system atrophy SDS Shy-Drager syndrome sporadic olivopontocerebellar atrophy Related Information ... A, Hulot JS, Morrison KE, Renton A, Sussmuth SD, Landwehrmeyer BG, Ludolph A, Agid Y, Brice A, ...

  19. Cytokeratin 8 in Association with sdLDL and ELISA Development

    PubMed Central

    Ashmaig, Mohmed

    2015-01-01

    Background: Cardiovascular disease (CVD) remains the leading cause of morbidity and mortality worldwide. Cytokeratins (CKs) which may also be expressed in vascular smooth muscle cells (SMCs) are generally considered to be markers for the differentiation of epithelial cells. Small, dense, low-density lipoprotein (sdLDL) particles, also termed LDL-IV, independently predict risk of CVD. Aims: The aims of this study were to develop an analytical method, apart from ultracentrifugation capable of isolating sdLDL in order to study any associated proteins. Materials and Methods: Using modified gradient gel electrophoresis (GGE), de-identified sdLDL-enriched plasma was used to physically elute and isolate sdLDL particles. To validate the finding, additional plasma from 77 normal and 48 higher risk subjects were used to measure sdLDL particles and CK8. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting method were used to identify the characteristics of proteins associated with sdLDL. An enzyme-linked immunosorbent assay (ELISA) method was developed and validated for the measurement of CK8 in plasma. Results: The validation of the CK8 ELISA method showed good analytical performance. The isolated sdLDL particles were verified with nondenaturing GGE with the apolipoprotein B component confirmed by Western immunoblotting. Confirmed by SDS-PAGE and Western immunoblotting, CK8 was associated with sdLDL. Two-tailed statistical analysis showed that CK8 and sdLDL particles were significantly higher in the high-risk CVD group compared to control group (P < 0.01 and P < 0.01, respectively). Conclusion: This study reports a novel association between CK8 and sdLDL in individuals with CVD who have a predominance of sdLDL. PMID:26713292

  20. Tri-Axial Accelerometry and Heart Rate Telemetry: Relation and Agreement with Behavioral Observation in Elementary Physical Education

    ERIC Educational Resources Information Center

    Scruggs, Philip W.; Beveridge, Sandy K.; Clocksin, Brian D.

    2005-01-01

    The relation and agreement of tri-axial accelerometry and heart rate telemetry in measuring moderate to vigorous physical activity were examined in association to behavioral observation during 1st- and 2nd-grade physical education. In Study 1, physical activity measures of heart rate and behavioral observation were collected on 346 participants…

  1. On the Components of Segregation Distortion in DROSOPHILA MELANOGASTER. II. Deletion Mapping and Dosage Analysis of the SD Locus

    PubMed Central

    Brittnacher, John G.; Ganetzky, Barry

    1983-01-01

    Segregation distorter (SD) chromosomes are preferentially transmitted to offspring from heterozygous SD/SD+ males owing to the induced dysfunction of the SD+-bearing sperm. This phenomenon involves at least two major loci: the Sd locus whose presence is necessary for distortion to occur and the Rsp locus which acts as the site of Sd action. Several additional loci on SD chromosomes enhance distortion.—In a previous study deletions were used to map the Sd locus and to determine some of its properties. We have extended this analysis with the isolation and characterization of 14 new deletions in the Sd region. From our results we conclude (1) SD chromosomes contain a single Sd locus located in region 37D2-6 of the salivary gland chromosome map. Deletion of this locus in any of three SD chromosomes now studied results in complete loss of ability to distort a sensitive chromosome; (2) the reduced male fecundity observed in many homozygous SD or SDi/SDj combinations is due at least in part to the action of the Sd locus. The fecundity of these males can be substantially increased by deletion of one Sd locus. Thus, it is the presence of two doses of Sd rather than the absence of Sd+ that produces the lowered male fecundity in SD homozygotes; (3) Sd behaves as a neomorph, whereas Sd+, if it exists at all, is amorphic with respect to segregation distortion; (4) these results support a model in which the Sd product is made in limiting amounts and the interaction of this product with the Rsp locus causes sperm dysfunction. The Sd product appears to act preferentially at Rsps (sensitive-Responder) but may also act at Rspi (insensitive-Responder). PMID:17246120

  2. Occurrence of Spontaneous Tumors in the Central Nervous System (CNS) of F344 and SD Rats

    PubMed Central

    Nagatani, Mariko; Kudo, Kayoko; Yamakawa, Seiki; Ohira, Toko; Yamaguchi, Yuko; Ikezaki, Shinichiro; Suzuki, Isamu; Saito, Tsubasa; Hoshiya, Toru; Tamura, Kazutoshi; Uchida, Kazuyuki

    2013-01-01

    In order to accurately assess the carcinogenicity of chemicals with regard to rare tumors such as rat CNS tumors, sufficient information about spontaneous tumors are very important. This paper presents the data on the type, incidence and detected age of CNS tumors in F344/DuCrlCrlj (a total of 1363 males and 1363 females) and Crl:CD(SD) rats (a total of 1650 males and 1705 females) collected from in-house background data-collection studies and control groups of carcinogenicity studies at our laboratory, together with those previously reported in F344 and SD rats. The present data on F344/DuCrlCrlj rats (F344 rats) and Crl:CD(SD) rats (SD rats) clarified the following. (1) The incidences of all CNS tumors observed in F344 rats were less than 1%. (2) The incidences of malignant astrocytoma and granular cell tumor were higher in male SD rats than in female SD rats. (3) The incidences of astrocytoma and granular cell tumor were higher in SD rats than in F344 rats. (4) Among astrocytoma, oligodendroglioma and granular cell tumor, oligodendroglioma was detected at the youngest age, followed by astrocytoma, and ultimately, granular cell tumor developed in both strains. The incidences observed in our study were almost consistent with those previously reported in F344 and SD rats. PMID:24155559

  3. Quantum phase transitional patterns in the SD-pair shell model

    SciTech Connect

    Luo Yanan; Meng Xiangfei; Zhang Yu; Pan Feng; Draayer, Jerry P.

    2009-07-15

    Patterns of shape-phase transition in the proton-neutron coupled systems are studied within the SD-pair shell model. The results show that some transitional patterns in the SD-pair shell model are similar to the U(5)-SU(3) and U(5)-SO(6) transitions with signatures of the critical point symmetry of the interacting boson model.

  4. 32. DETAIL OF WALL SHOWN IN SD231. BEHIND WALL FRAMING ...

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

    32. DETAIL OF WALL SHOWN IN SD-2-31. BEHIND WALL FRAMING IS SAMPLING ROOM WITH WOOD SAMPLING ELEVATOR. CRUSHED OXIDIZED ORE BIN ON LEFT (SOUTH). - Bald Mountain Gold Mill, Nevada Gulch at head of False Bottom Creek, Lead, Lawrence County, SD

  5. The effects of specimen width on tensile properties of triaxially braided textile composites

    NASA Technical Reports Server (NTRS)

    Masters, John E.; Ifju, Peter G.; Pastore, Christopher M.; Bogdanovich, Alexander E.

    1993-01-01

    The objective of this study was to examine the effect of the unit cell architecture on the mechanical response of textile reinforced composite materials. Specifically, the study investigated the effect of unit cell size on the tensile properties of 2D triaxially braided graphite epoxy laminates. The figures contained in this paper reflect the presentation given at the conference. They may be divided into four sections: (1) a short definition of the material system tested; (2) a statement of the problem and a review of the experimental results; (3) experimental results consist of a Moire interferometry study of the strain distribution in the material plus modulus and strength measurements; and (4) a short summary and a description of future work will close the paper.

  6. Triaxial rotor model description of E2 properties in Os186,188,190,192

    NASA Astrophysics Data System (ADS)

    Allmond, J. M.; Zaballa, R.; Oros-Peusquens, A. M.; Kulp, W. D.; Wood, J. L.

    2008-07-01

    The triaxial rotor model with independent inertia and electric quadrupole tensors is applied to the description of the extensive set of E2 matrix elements available for Os186,188,190,192. Most large and medium transition E2 matrix elements can be reproduced to within ~10%, and most diagonal elements to within ~30%. Most small transition matrix elements can be reproduced to within ~30%, and they support the interference effect exhibited by the model between the inertia and E2 tensors: this is a new feature of quantum rotor models. The diagonal E2 matrix elements at higher spins in the K=2 band are extremely sensitive to admixtures of higher K values: the low experimental values in Os190,192 indicate significant admixtures of K=4 components. Attention is given to the Kπ=4+ bands in these nuclei and the controversial issue of whether they are of quadrupole or hexadecapole nature.

  7. The effects of compressive sensing on extracted features from tri-axial swallowing accelerometry signals

    NASA Astrophysics Data System (ADS)

    Sejdić, Ervin; Movahedi, Faezeh; Zhang, Zhenwei; Kurosu, Atsuko; Coyle, James L.

    2016-05-01

    Acquiring swallowing accelerometry signals using a comprehensive sensing scheme may be a desirable approach for monitoring swallowing safety for longer periods of time. However, it needs to be insured that signal characteristics can be recovered accurately from compressed samples. In this paper, we considered this issue by examining the effects of the number of acquired compressed samples on the calculated swallowing accelerometry signal features. We used tri-axial swallowing accelerometry signals acquired from seventeen stroke patients (106 swallows in total). From acquired signals, we extracted typically considered signal features from time, frequency and time-frequency domains. Next, we compared these features from the original signals (sampled using traditional sampling schemes) and compressively sampled signals. Our results have shown we can obtain accurate estimates of signal features even by using only a third of original samples.

  8. Experimental and Analytical Characterization of the Macromechanical Response for Triaxial Braided Composite Materials

    NASA Technical Reports Server (NTRS)

    Littell, Justin D.

    2013-01-01

    Increasingly, carbon composite structures are being used in aerospace applications. Their highstrength, high-stiffness, and low-weight properties make them good candidates for replacing many aerospace structures currently made of aluminum or steel. Recently, many of the aircraft engine manufacturers have developed new commercial jet engines that will use composite fan cases. Instead of using traditional composite layup techniques, these new fan cases will use a triaxially braided pattern, which improves case performance. The impact characteristics of composite materials for jet engine fan case applications have been an important research topic because Federal regulations require that an engine case be able to contain a blade and blade fragments during an engine blade-out event. Once the impact characteristics of these triaxial braided materials become known, computer models can be developed to simulate a jet engine blade-out event, thus reducing cost and time in the development of these composite jet engine cases. The two main problems that have arisen in this area of research are that the properties for these materials have not been fully determined and computationally efficient computer models, which incorporate much of the microscale deformation and failure mechanisms, are not available. The research reported herein addresses some of the deficiencies present in previous research regarding these triaxial braided composite materials. The current research develops new techniques to accurately quantify the material properties of the triaxial braided composite materials. New test methods are developed for the polymer resin composite constituent and representative composite coupons. These methods expand previous research by using novel specimen designs along with using a noncontact measuring system that is also capable of identifying and quantifying many of the microscale failure mechanisms present in the materials. Finally, using the data gathered, a new hybrid

  9. Finite Element Model for Failure Study of Two-Dimensional Triaxially Braided Composite

    NASA Technical Reports Server (NTRS)

    Li, Xuetao; Binienda, Wieslaw K.; Goldberg, Robert K.

    2010-01-01

    A new three-dimensional finite element model of two-dimensional triaxially braided composites is presented in this paper. This meso-scale modeling technique is used to examine and predict the deformation and damage observed in tests of straight sided specimens. A unit cell based approach is used to take into account the braiding architecture as well as the mechanical properties of the fiber tows, the matrix and the fiber tow-matrix interface. A 0 deg / plus or minus 60 deg. braiding configuration has been investigated by conducting static finite element analyses. Failure initiation and progressive degradation has been simulated in the fiber tows by use of the Hashin failure criteria and a damage evolution law. The fiber tow-matrix interface was modeled by using a cohesive zone approach to capture any fiber-matrix debonding. By comparing the analytical results to those obtained experimentally, the applicability of the developed model was assessed and the failure process was investigated.

  10. A generalized Nadai failure criterion for both crystalline and clastic rocks based on true triaxial tests

    NASA Astrophysics Data System (ADS)

    Haimson, Bezalel; Chang, Chandong; Ma, Xiaodong

    2016-04-01

    The UW true triaxial testing system enables the application of independent compressive loads to cuboidal specimens (19×19×38 mm) along three principal directions. We used the apparatus to conduct extensive series of experiments in three crystalline rocks (Westerly granite, KTB amphibolite, and SAFOD granodiorite) and three clastic rocks of different porosities [TCDP siltstone (7%), Coconino sandstone (17%), and Bentheim sandstone (24%)]. For each rock, several magnitudes of σ3 were employed, between 0 MPa and 100-160 MPa, and for every σ3, σ2 was varied from test to test between σ2 = σ3 and σ2=(0.4 to 1.0) σ1.Testing consisted of keeping σ2and σ3constant, and raising σ1to failure (σ1,peak). The results, plotted as σ1,peakvs. σ2for each σ3 used, highlight the undeniable effect of σ2on the compressive failure of rocks. For each level of σ3, the lowest σ2 tested (σ2 = σ3) yielded the data point used for conventional-triaxial failure criterion. However, for the same σ3 and depending on σ2 magnitude, the maximum stress bringing about failure (σ1,peak) may be considerably higher, by as much as 50% in crystalline rocks, or 15% in clastic rocks, over that in a conventional triaxial test. An important consequence is that use of a Mohr-type criterion leads to overly conservative predictions of failure. The true triaxial test results demonstrate that a criterion in terms of all (three principal stresses is necessary to characterize failure. Thus, we propose a 'Generalized Nadai Criterion' (GNC) based on Nadai (1950), i.e. expressed in terms of the two stress invariants at failure (f), τoct,f = βσoct,f, where τoct,f = 1/3[(σ1,peak ‑σ2)2+(σ2 ‑σ3)2+(σ3 ‑σ1,peak)2]0.5 and σoct,f = (σ1,peak + σ2 + σ3)/3, and β is a function that varies from rock to rock. Moreover, the criterion depends also on the relative magnitude of σ2, represented by a parameter b [= (σ2 - σ3)/(σ1,peak - σ3)]. For each octahedral shear stress at failure (

  11. Critical point symmetry for the spherical to triaxially deformed shape phase transition

    NASA Astrophysics Data System (ADS)

    Zhang, Yu; Pan, Feng; Luo, Yan-An; Draayer, J. P.

    2015-12-01

    The critical point T(5) symmetry for the spherical to triaxially deformed shape phase transition is introduced from the Bohr Hamiltonian by approximately separating variables at a given γ deformation with 0 ° ≤ γ ≤ 30 °. The resulting spectral and E2 properties have been investigated in detail. The results indicate that the original X(5) and Z(5) critical point symmetries can be naturally realized within the T(5) model in the γ = 0 ° and γ = 30 ° limit, respectively, which thus provides a dynamical connection between the two symmetries. Comparison of the theoretical calculations for 148Ce, 160Yb, 192Pt and 194Pt with the corresponding experimental data is also made, which indicates that, to some extent, possible asymmetric deformation may be involved in these transitional nuclei.

  12. The Fracture Characteristic of Three Collinear Cracks under True Triaxial Compression

    PubMed Central

    Liu, Jianjun; Zhu, Zheming; Wang, Bo

    2014-01-01

    The mechanical behavior of multicracks under compression has become a very important project in the field of fracture mechanics and rock mechanics. In this paper, experimental and numerical studies on the fracture property of three collinear cracks under compression were implemented. The specimens were a square concrete plate, and the cracks were made by a very thin film. The tests were conducted by using true triaxial loading device. In the numerical study, the Abaqus code was employed. The effect of crack orientation and the confining stress on cracked specimen compressive strength were investigated. The results show that the critical stresses of cracked specimens change with crack inclination angles, and, as the angle is 45°, the critical stress is the lowest; the critical stresses increase with the confining stresses. PMID:24790569

  13. The fracture characteristic of three collinear cracks under true triaxial compression.

    PubMed

    Liu, Jianjun; Zhu, Zheming; Wang, Bo

    2014-01-01

    The mechanical behavior of multicracks under compression has become a very important project in the field of fracture mechanics and rock mechanics. In this paper, experimental and numerical studies on the fracture property of three collinear cracks under compression were implemented. The specimens were a square concrete plate, and the cracks were made by a very thin film. The tests were conducted by using true triaxial loading device. In the numerical study, the Abaqus code was employed. The effect of crack orientation and the confining stress on cracked specimen compressive strength were investigated. The results show that the critical stresses of cracked specimens change with crack inclination angles, and, as the angle is 45°, the critical stress is the lowest; the critical stresses increase with the confining stresses. PMID:24790569

  14. Assessment of the mechanical properties of sisal fiber-reinforced silty clay using triaxial shear tests.

    PubMed

    Wu, Yankai; Li, Yanbin; Niu, Bin

    2014-01-01

    Fiber reinforcement is widely used in construction engineering to improve the mechanical properties of soil because it increases the soil's strength and improves the soil's mechanical properties. However, the mechanical properties of fiber-reinforced soils remain controversial. The present study investigated the mechanical properties of silty clay reinforced with discrete, randomly distributed sisal fibers using triaxial shear tests. The sisal fibers were cut to different lengths, randomly mixed with silty clay in varying percentages, and compacted to the maximum dry density at the optimum moisture content. The results indicate that with a fiber length of 10 mm and content of 1.0%, sisal fiber-reinforced silty clay is 20% stronger than nonreinforced silty clay. The fiber-reinforced silty clay exhibited crack fracture and surface shear fracture failure modes, implying that sisal fiber is a good earth reinforcement material with potential applications in civil engineering, dam foundation, roadbed engineering, and ground treatment.

  15. Triaxial digital fluxgate magnetometer for NASA applications explorer mission: Results of tests of critical elements

    NASA Technical Reports Server (NTRS)

    Mcleod, M. G.; Means, J. D.

    1977-01-01

    Tests performed to prove the critical elements of the triaxial digital fluxgate magnetometer design were described. A method for improving the linearity of the analog to digital converter portion of the instrument was studied in detail. A sawtooth waveform was added to the signal being measured before the A/D conversion, and averaging the digital readings over one cycle of the sawtooth. It was intended to reduce bit error nonlinearities present in the A/D converter which could be expected to be as much as 16 gamma if not reduced. No such nonlinearities were detected in the output of the instrument which included the feature designed to reduce these nonlinearities. However, a small scale nonlinearity of plus or minus 2 gamma with a 64 gamma repetition rate was observed in the unit tested. A design improvement intended to eliminate this small scale nonlinearity was examined.

  16. Assessment of the mechanical properties of sisal fiber-reinforced silty clay using triaxial shear tests.

    PubMed

    Wu, Yankai; Li, Yanbin; Niu, Bin

    2014-01-01

    Fiber reinforcement is widely used in construction engineering to improve the mechanical properties of soil because it increases the soil's strength and improves the soil's mechanical properties. However, the mechanical properties of fiber-reinforced soils remain controversial. The present study investigated the mechanical properties of silty clay reinforced with discrete, randomly distributed sisal fibers using triaxial shear tests. The sisal fibers were cut to different lengths, randomly mixed with silty clay in varying percentages, and compacted to the maximum dry density at the optimum moisture content. The results indicate that with a fiber length of 10 mm and content of 1.0%, sisal fiber-reinforced silty clay is 20% stronger than nonreinforced silty clay. The fiber-reinforced silty clay exhibited crack fracture and surface shear fracture failure modes, implying that sisal fiber is a good earth reinforcement material with potential applications in civil engineering, dam foundation, roadbed engineering, and ground treatment. PMID:24982951

  17. Speed estimation from a tri-axial accelerometer using neural networks.

    PubMed

    Song, Yoonseon; Shin, Seungchul; Kim, Seunghwan; Lee, Doheon; Lee, Kwang H

    2007-01-01

    We propose a speed estimation method with human body accelerations measured on the chest by a tri-axial accelerometer. To estimate the speed we segmented the acceleration signal into strides measuring stride time, and applied two neural networks into the patterns parameterized from each stride calculating stride length. The first neural network determines whether the subject walks or runs, and the second neural network with different node interactions according to the subject's status estimates stride length. Walking or running speed is calculated with the estimated stride length divided by the measured stride time. The neural networks were trained by patterns obtained from 15 subjects and then validated by 2 untrained subjects' patterns. The result shows good agreement between actual and estimated speeds presenting the linear correlation coefficient r=0.9874. We also applied the method to the real field and track data.

  18. Transition saddle points and associated defects for a triaxially stretched FCC crystal

    NASA Astrophysics Data System (ADS)

    Delph, T. J.; Zimmerman, J. A.

    2016-05-01

    We demonstrate the use of a single-ended method for locating saddle points on the potential energy surface for a triaxially stretched FCC crystal governed by a Lennard-Jones potential. Single-ended methods require no prior knowledge of the defected state and are shown to have powerful advantages in this application, principally because the nature of the associated defects can be quite complicated and hence extremely difficult to predict ab initio. We find that while classical spherical cavitation occurs for high stretch values, for lower values the defect mode transitions to a non-spherical pattern without any apparent symmetries. This non-spherical mode plays the primary role in harmonic transition state theory predictions that are used to examine how instabilities vary with applied loading rate. Such a defect mode would be difficult to determine using double-ended methods for finding saddle points.

  19. A Table-Shaped Tactile Sensor for Detecting Triaxial Force on the Basis of Strain Distribution

    PubMed Central

    Lee, Jeong Il; Kim, Min-Gyu; Shikida, Mitsuhiro; Sato, Kazuo

    2013-01-01

    A slim and flexible tactile sensor applicable to the interaction of human and intelligent robots is presented. In particular, a simple sensing principle for decoupling of three-dimensional force is proposed. Sensitivity of the proposed tactile sensor is tested experimentally. To improve the sensitivity of the sensor, a table-shaped sensing element was designed. Table-shaped structure can convert an external acting force into concentrated internal stress. A “triaxial force decoupling algorithm” was developed by combining two-dimensional mapping data calculated by finite element analysis. The sensor was calibrated under normal and tangential forces. The external loads applied to the sensor could be decoupled independently as a function of the strain-gauge responses. PMID:24287546

  20. Ultrahigh-spin spectroscopy of {sup 159,160}Er: Observation of triaxial strongly deformed structures

    SciTech Connect

    Ollier, J.; Simpson, J.; Wang, X.; Riley, M. A.; Aguilar, A.; Teal, C.; Paul, E. S.; Nolan, P. J.; Petri, M.; Rigby, S. V.; Thomson, J.; Unsworth, C.; Carpenter, M. P.; Janssens, R. V. F.; Kondev, F. G.; Lauritsen, T.; Zhu, S.; Hartley, D. J.; Darby, I. G.; Ragnarsson, I.

    2009-12-15

    Three weakly populated high-spin rotational bands associated with the {gamma} decay of {sup 159}Er and {sup 160}Er were observed in fusion-evaporation reactions involving a beam of {sup 48}Ca at an energy of 215 MeV incident on a {sup 116}Cd target. The {gamma} decays were detected using the highly efficient Gammasphere spectrometer. The discovery of these bands, which extend discrete-line spectroscopy in these nuclei to ultrahigh spin of {approx}60({Dirac_h}/2{pi}), is consistent with recent observations of high-spin collective structures in isotopes of Er, Yb, and Tm around N=90. Cranked Nilsson-Strutinsky calculations suggest that these bands may arise from well-deformed triaxial configurations with either positive or negative {gamma} deformation.

  1. A new experimental technique for the analysis of concrete under high triaxial loading

    NASA Astrophysics Data System (ADS)

    Gabet, T.; Vu, X. H.; Malecot, Y.; Daudeville, L.

    2006-08-01

    Concrete is a building material used for sensitive infrastructures like dams or nuclear power reactors; however its behaviour remains badly known under extreme dynamical loading like rock falls, explosions or ballistic impacts. It is due both to the difficulty of reproducing experimentally such a loading and to the intrinsic complexity of concrete behaviour. Predicting its response under dynamic loading needs the experimental characterization of its static behaviour in compression under very high confinement. This paper first presents a new large capacity triaxial press and the manufacturing and testing procedures developed to perform the tests. Plain concrete specimens (centimetric aggregate dimension) were submitted to different loading paths up to an ultimate state associated to failure.

  2. Loading and Boundary Condition Influences in a Poroelastic Finite Element Model of Cartilage Stresses in a Triaxial Compression Bioreactor

    PubMed Central

    Kallemeyn, Nicole A; Grosland, Nicole M; Pedersen, Doug R; Martin, James A; Brown, Thomas D

    2006-01-01

    Background: We developed a poroelastic finite element (FE) model of cartilage in dynamic triaxial compression to parametrically analyze the effects of loading and boundary conditions on a baseline model. Conventional mechanical tests on articular cartilage such as confined and unconfined compression, indentation, etc., do not fully allow for modulation of compression and shear at physiological levels whereas triaxial compression does. A Triaxial Compression Bioreactor, or TRIAX, has been developed to study chondrocyte responses to multi-axial stress conditions under cyclic loading. In the triaxial setting, however, a cartilage explant's physical testing environment departs from the ideal homogeneous stress state that would occur from strict linear superposition of the applied axial and transverse pressure. Method of Approach: An axisymmetric poroelastic FE model of a cartilage explant (4 mm diameter, 1.5 mm thick) in cyclic triaxial compression was created. Axial and transverse loads (2 MPa at 1 Hz.) were applied via a platen and containment sheath. Parameters of interest included the rise time and magnitude of the applied load, in addition to the containment sheath modulus and the friction coefficient at the cartilage/platen interfaces. Metrics of interest in addition to whole explant axial strain included axial (surface normal) stress, shear stress, pore pressure, and the fluid load carriage fraction within the explant. Results: Strain results were compared to experimental data from explants tested in the TRIAX under conditions similar to the baseline model. Explant biomechanics varied considerably over numbers of load cycles and parameter values. Cyclic loading caused an increase in accumulated strain for the various loading and boundary conditions. Conclusions: Unlike what would be expected from linear superposition of the homogeneous stresses from the applied axial and transverse pressure, we have shown that the stress state within the TRIAX is considerably

  3. Evaluation of Instability Phenomena in Sands: Plane Strain Versus Triaxial Conditions

    NASA Technical Reports Server (NTRS)

    Alshibli, Khalid A.

    2001-01-01

    Extensive research was carried out in the 1950s on theories of plasticity to extend the concepts developed for metals to materials that failed according to the Mohr-Coulomb criterion. The new ideas made it possible to merge the two distinct concepts (strength and deformation techniques) into one that relies on better understanding of plasticity and resulted in a rapid growth in the field of constitutive modeling of soil behavior. At the same time advanced experimental apparatuses and laboratory procedures were developed to calibrate the models. However, most laboratory experiments on granular materials are performed under Conventional Triaxial Conditions (CTC) for the purposes of evaluating constitutive behavior and stability properties, whereas most geotechnical field problems are closer to the Plane Strain (PS) condition. The triaxial tests performed in most laboratories comprise a simplification over in situ states and allow easier and robust experimentation. Most landslide problems, failure of soils beneath shallow and deep foundations, and failure of retaining structures, are cases that can generally be considered as plane strain. Strength and deformation characteristics of granular materials loaded in plane strain may be considerably different from those observed in CTC. Most studies on sands were limited to evaluating the constitutive behavior and in some cases extended to briefly describing the associated instability phenomena. This paper presents the results of a series of PS and CTC experiments performed on fine uniform silica sand known as F-75 Ottawa sand. Advanced analysis techniques were used to study the instability phenomena, which yielded very accurate measurements of shear bands occurrences and patterns. Destructive thin-sectioning technique along with monitoring the specimen surface deformation was used in the PS experiments and Computed Tomography (CT) was used to investigate the progress of primary and secondary shear bands in specimens

  4. Mineralogic variation in drill holes USW NRG-6, NRG-7/7a, SD-7, SD-9, SD-12, and UZ{number_sign}14: New data from 1996--1997 analyses

    SciTech Connect

    Chipera, S.J.; Vaniman, D.T.; Bish, D.L.; Carey, J.W.

    1997-05-30

    New quantitative X-ray diffraction (QXRD) mineralogic data have been obtained for samples from drill holes NRG-6, NRG-7/7A, SD-7, SD-9, SD- 12, and UZ{number_sign}14. In addition, new QXRD analyses were obtained on samples located in a strategic portion of drill hole USW H-3. These data improve our understanding of the mineral stratigraphy at Yucca Mountain, and they further constrain the 3-D Mineralogic Model of Yucca Mountain. Some of the unexpected findings include the occurrence of the zeolite chabazite in the vitric zone of USW SD-7, broad overlap of vitric and zeolitic horizons (over vertical ranges up to 70 m), and the previously unrecognized importance of the bedded tuft beneath the Calico Hills Formation as a subunit with generally more extensive zeolitization than the Calico Hills Formation in the southern part of the potential repository area. Reassessment of data from drill hole USW H-5 suggests that the zeolitization of this bedded unit occurs in the northwestern part of the repository exploration block as well. Further analyses of the same interval in USW H-3, however, have not permitted the same conclusion to be reached for the southwestern part of the repository block because of the much poorer quality of the cuttings in H-3 compared with those from H-5. X-ray fluorescence (XRF) chemical data for drill holes USW SD-7, 9, and 12 show that the zeolitic horizons provide a >10 million year record of retardation of Sr transport, although the data also show that simplistic models of one-dimensional downward flow in the unsaturated zone (UZ) are inadequate. Complex interstratification of zeolites and glass, with highly variable profiles between drill cores, point to remaining problems in constructing detailed mineral stratigraphies. However, the new data in this report provide important information for constructing bounding models of zeolite stratigraphy for transport calculations.

  5. Bar formation and evolution in disc galaxies with gas and a triaxial halo: morphology, bar strength and halo properties

    NASA Astrophysics Data System (ADS)

    Athanassoula, E.; Machado, Rubens E. G.; Rodionov, S. A.

    2013-03-01

    We follow the formation and evolution of bars in N-body simulations of disc galaxies with gas and/or a triaxial halo. We find that both the relative gas fraction and the halo shape play a major role in the formation and evolution of the bar. In gas-rich simulations, the disc stays near-axisymmetric much longer than in gas-poor ones, and, when the bar starts growing, it does so at a much slower rate. Because of these two effects combined, large-scale bars form much later in gas-rich than in gas-poor discs. This can explain the observation that bars are in place earlier in massive red disc galaxies than in blue spirals. We also find that the morphological characteristics in the bar region are strongly influenced by the gas fraction. In particular, the bar at the end of the simulation is much weaker in gas-rich cases. The quality of our simulations is such as to allow us to discuss the question of bar longevity because the resonances are well resolved and the number of gas particles is sufficient to describe the gas flow adequately. In no case did we find a bar which was destroyed. Halo triaxiality has a dual influence on bar strength. In the very early stages of the simulation it induces bar formation to start earlier. On the other hand, during the later, secular evolution phase, triaxial haloes lead to considerably less increase of the bar strength than spherical ones. The shape of the halo evolves considerably with time. We confirm previous results of gas-less simulations that find that the inner part of an initially spherical halo can become elongated and develop a halo bar. However we also show that, on the contrary, in gas-rich simulations, the inner parts of an initially triaxial halo can become rounder with time. The main body of initially triaxial haloes evolves towards sphericity, but in initially strongly triaxial cases it stops well short of becoming spherical. Part of the angular momentum absorbed by the halo generates considerable rotation of the halo

  6. Novel triaxial structure in low-lying states of neutron-rich nuclei around A ≈100

    NASA Astrophysics Data System (ADS)

    Xiang, J.; Yao, J. M.; Fu, Y.; Wang, Z. H.; Li, Z. P.; Long, W. H.

    2016-05-01

    Background: In recent years, the study of triaxiality in the low-lying states of atomic nuclei with transition character or shape coexistence has been of great interest. Previous studies indicate that the neutron-rich nuclei in the A ˜100 mass region with Z ˜40 ,N ˜60 serve as good grounds for examining the role of triaxiality in nuclear low-lying states. Purpose: The aim of this work is to provide a microscopic study of low-lying states for nuclei in the A ˜100 mass regions and to examine in detail the role of triaxiality in the shape-coexistence phenomena and the variation of shape with the isospin and spin values at the beyond mean-field level. Method: The starting point of our method is a set of relativistic mean-field plus BCS wave functions generated with a constraint on triaxial deformations (β ,γ ) . The excitation energies and electric multipole transition strengths of low-lying states are calculated by solving a five-dimensional collective Hamiltonian (5DCH) with parameters determined by the mean-field wave functions. Results: The low-lying states of Mo isotopes and of N =60 isotones in the A ˜100 mass region are calculated. The results indicate that triaxiality is essential to reproduce the data of excitation energies and electric quadrupole transition strengths in low-lying states and plays an important role in the shape evolution as a function of nucleon number. However, the decrease of nuclear collectivity with the increase of angular momentum in neutron-rich Mo isotopes has not been reproduced. Conclusions: The evolution of nuclear collectivity in the low-lying states of neutron-rich nuclei in the A ˜100 mass region as a function of nucleon number is governed by the novel triaxial structure. However, the mechanism that governs the variation of nuclear shape with spin in Mo isotopes remains unclear and deserves further investigation by taking into account the effects other than the collective motions.

  7. Molecular Characterization of a Novel Bovine Viral Diarrhea Virus Isolate SD-15

    PubMed Central

    Zhu, Lisai; Lu, Haibing; Cao, Yufeng; Gai, Xiaochun; Guo, Changming; Liu, Yajing; Liu, Jiaxu; Wang, Xinping

    2016-01-01

    As one of the major pathogens, bovine viral diarrhea virus caused a significant economic loss to the livestock industry worldwide. Although BVDV infections have increasingly been reported in China in recent years, the molecular aspects of those BVDV strains were barely characterized. In this study, we reported the identification and characterization of a novel BVDV isolate designated as SD-15 from cattle, which is associated with an outbreak characterized by severe hemorrhagic and mucous diarrhea with high morbidity and mortality in Shandong, China. SD-15 was revealed to be a noncytopathic BVDV, and has a complete genomic sequence of 12,285 nucleotides that contains a large open reading frame encoding 3900 amino acids. Alignment analysis showed that SD-15 has 93.8% nucleotide sequence identity with BVDV ZM-95 isolate, a previous BVDV strain isolated from pigs manifesting clinical signs and lesions resembling to classical swine fever. Phylogenetic analysis clustered SD-15 to a BVDV-1m subgenotype. Analysis of the deduced amino acid sequence of glycoproteins revealed that E2 has several highly conserved and variable regions within BVDV-1 genotypes. An additional N-glycosylation site (240NTT) was revealed exclusively in SD-15-encoded E2 in addition to four potential glycosylation sites (Asn-X-Ser/Thr) shared by all BVDV-1 genotypes. Furthermore, unique amino acid and linear epitope mutations were revealed in SD-15-encoded Erns glycoprotein compared with known BVDV-1 genotype. In conclusion, we have isolated a noncytopathic BVDV-1m strain that is associated with a disease characterized by high morbidity and mortality, revealed the complete genome sequence of the first BVDV-1m virus originated from cattle, and found a unique glycosylation site in E2 and a linear epitope mutation in Erns encoded by SD-15 strain. Those results will broaden the current understanding of BVDV infection and lay a basis for future investigation on SD-15-related pathogenesis. PMID:27764206

  8. Plastic cap evolution law derived from induced transverse isotropy in dilatational triaxial compression.

    SciTech Connect

    Macon, David James; Brannon, Rebecca Moss; Strack, Otto Eric

    2014-02-01

    Mechanical testing of porous materials generates physical data that contain contributions from more than one underlying physical phenomenon. All that is measurable is the (3z(Bensemble(3y (Bhardening modulus. This thesis is concerned with the phenomenon of dilatation in triaxial compression of porous media, which has been modeled very accurately in the literature for monotonic loading using models that predict dilatation under triaxial compression (TXC) by presuming that dilatation causes the cap to move outwards. These existing models, however, predict a counter-intuitive (and never validated) increase in hydrostatic compression strength. This work explores an alternative approach for modeling TXC dilatation based on allowing induced elastic anisotropy (which makes the material both less stiff and less strong in the lateral direction) with no increase in hydrostatic strength. Induced elastic anisotropy is introduced through the use of a distortion operator. This operator is a fourth-order tensor consisting of a combination of the undeformed stiffness and deformed compliance and has the same eigenprojectors as the elastic compliance. In the undeformed state, the distortion operator is equal to the fourth-order identity. Through the use of the distortion operator, an evolved stress tensor is introduced. When the evolved stress tensor is substituted into an isotropic yield function, a new anisotropic yield function results. In the case of the von Mises isotropic yield function (which contains only deviatoric components), it is shown that the distortion operator introduces a dilatational contribution without requiring an increase in hydrostatic strength. In the thesis, an introduction and literature review of the cap function is given. A transversely isotropic compliance is presented, based on a linear combination of natural bases constructed about a transverse-symmetry axis. Using a probabilistic distribution of cracks constructed for the case of transverse isotropy

  9. Effect of Microscopic Damage Events on Static and Ballistic Impact Strength of Triaxial Braid Composites

    NASA Technical Reports Server (NTRS)

    Littell, Justin D.; Binienda, Wieslaw K.; Arnold, William A.; Roberts, Gary d.; Goldberg, Robert K.

    2008-01-01

    In previous work, the ballistic impact resistance of triaxial braided carbon/epoxy composites made with large flat tows (12k and 24k) was examined by impacting 2 X2 X0.125" composite panels with gelatin projectiles. Several high strength, intermediate modulus carbon fibers were used in combination with both untoughened and toughened matrix materials. A wide range of penetration thresholds were measured for the various fiber/matrix combinations. However, there was no clear relationship between the penetration threshold and the properties of the constituents. During some of these experiments high speed cameras were used to view the failure process, and full-field strain measurements were made to determine the strain at the onset of failure. However, these experiments provided only limited insight into the microscopic failure processes responsible for the wide range of impact resistance observed. In order to investigate potential microscopic failure processes in more detail, quasi-static tests were performed in tension, compression, and shear. Full-field strain measurement techniques were used to identify local regions of high strain resulting from microscopic failures. Microscopic failure events near the specimen surface, such as splitting of fiber bundles in surface plies, were easily identified. Subsurface damage, such as fiber fracture or fiber bundle splitting, could be identified by its effect on in-plane surface strains. Subsurface delamination could be detected as an out-of-plane deflection at the surface. Using this data, failure criteria could be established at the fiber tow level for use in analysis. An analytical formulation was developed to allow the microscopic failure criteria to be used in place of macroscopic properties as input to simulations performed using the commercial explicit finite element code, LS-DYNA. The test methods developed to investigate microscopic failure will be presented along with methods for determining local failure criteria

  10. Integral equation model of light scattering by an oriented monodisperse system of triaxial dielectric ellipsoids: application in ectacytometry.

    PubMed

    Stamatakos, G S; Yova, D; Uzunoglu, N K

    1997-09-01

    A novel mathematical model of light scattering by an oriented monodisperse system of triaxial dielectric ellipsoids of complex index of refraction is presented. It is based on an integral equation solution to the scattering of a plane electromagnetic wave by a single triaxial dielectric ellipsoid. Both the position and the orientation of a single representative scatterer in a given coordinate system are considered arbitrary. A Monte Carlo simulation is developed to reproduce the diffraction pattern of a population of aligned ellipsoids. As an example of practical importance, light scattering by a population of erythrocytes subjected to intense shear stress is modeled. Agreement with experimental observations and the anomalous diffraction theory is illustrated. Thus a novel check of the electromagnetic basis of ektacytometry is provided. Furthermore, the versatility of the integral equation method, particularly in the advent of parallel processing systems, is demonstrated. PMID:18259511

  11. High-spin level structure of {sup 115}Rh: Evolution of triaxiality in odd-even Rh isotopes

    SciTech Connect

    Liu, S. H.; Gelberg, A.; Gu, L.; Yeoh, E. Y.; Zhu, S. J.; Luo, Y. X.; Rasmussen, J. O.; Ma, W. C.; Daniel, A. V.; Oganessian, Yu. Ts.; Ter-Akopian, G. M.

    2011-07-15

    High-spin excited states in the neutron-rich nucleus {sup 115}Rh have been identified for the first time by studying prompt {gamma} rays from the spontaneous fission of {sup 252}Cf with the Gammasphere detector array. A new yrast band and a sideband are built in {sup 115}Rh. This level scheme is proposed to be built on the 7/2{sup +} ground state. The existence of a large signature splitting and an yrare band in {sup 115}Rh shows typical features of a triaxially deformed nucleus. The rigid triaxial rotor plus particle model is used to interpret the level structure of {sup 115}Rh. The level energies, the {gamma} branching ratios, the large signature splitting in the yrast band, and the inverted signature splitting in the yrare band in {sup 115}Rh are reproduced very well. Strong K mixing occurs in {sup 115}Rh at high spin.

  12. Real-time estimation of daily physical activity intensity by a triaxial accelerometer and a gravity-removal classification algorithm.

    PubMed

    Ohkawara, Kazunori; Oshima, Yoshitake; Hikihara, Yuki; Ishikawa-Takata, Kazuko; Tabata, Izumi; Tanaka, Shigeho

    2011-06-01

    We have recently developed a simple algorithm for the classification of household and locomotive activities using the ratio of unfiltered to filtered synthetic acceleration (gravity-removal physical activity classification algorithm, GRPACA) measured by a triaxial accelerometer. The purpose of the present study was to develop a new model for the immediate estimation of daily physical activity intensities using a triaxial accelerometer. A total of sixty-six subjects were randomly assigned into validation (n 44) and cross-validation (n 22) groups. All subjects performed fourteen activities while wearing a triaxial accelerometer in a controlled laboratory setting. During each activity, energy expenditure was measured by indirect calorimetry, and physical activity intensities were expressed as metabolic equivalents (MET). The validation group displayed strong relationships between measured MET and filtered synthetic accelerations for household (r 0·907, P < 0·001) and locomotive (r 0·961, P < 0·001) activities. In the cross-validation group, two GRPACA-based linear regression models provided highly accurate MET estimation for household and locomotive activities. Results were similar when equations were developed by non-linear regression or sex-specific linear or non-linear regressions. Sedentary activities were also accurately estimated by the specific linear regression classified from other activity counts. Therefore, the use of a triaxial accelerometer in combination with a GRPACA permits more accurate and immediate estimation of daily physical activity intensities, compared with previously reported cut-off classification models. This method may be useful for field investigations as well as for self-monitoring by general users.

  13. Self-Consistent Tilted-Axis-Cranking Study of Triaxial Strongly Deformed Bands in ^{158}Er at Ultrahigh Spin

    SciTech Connect

    Shi, Yue; Dobaczewski, J.; Frauendorf, S.; Nazarewicz, Witold; Pei, J. C.; Xu, F. R.; Nikolov, N.

    2012-01-01

    Stimulated by recent experimental discoveries, triaxial strongly deformed (TSD) states in ^{158}Er at ultrahigh spins have been studied by means of the Skyrme-Hartree-Fock model and the tilted-axis-cranking method. Restricting the rotational axis to one of the principal axes - as done in previous cranking calculations - two well-defined TSD minima in the total Routhian surface are found for a given configuration: one with positive and another with negative triaxial deformation gamma. By allowing the rotational axis to change direction, the higher-energy minimum is shown to be a saddle point. This resolves the long-standing question of the physical interpretation of the two triaxial minima at a very similar quadrupole shape obtained in the principal axis cranking approach. Several TSD configurations have been predicted, including a highly deformed band expected to cross lesser elongated TSD bands at the highest spins. Its transitional quadrupole moment Q_{t} ~ 10.5 eb is close to the measured value of ~11 eb; hence, it is a candidate for the structure observed in experiment.

  14. The Triaxial Ellipsoid Diameters and Rotational Pole of Asteroid (9) Metis from AO at Gemini and Keck

    NASA Astrophysics Data System (ADS)

    Drummond, Jack D.; Merline, W. J.; Conrad, A.; Dumas, C.; Tamblyn, P.; Christou, J.; Carry, B.; Chapman, C.

    2012-10-01

    From Adaptive Optics (AO) images of (9) Metis at 14 epochs over 2008 December 8 and 9 at Gemini North, triaxial ellipsoid diameters of 218x175x112 km are derived with fitting uncertainties of 3x3x47 km. However, by including just two more AO images from Keck-II in June and August of 2003 in a global fit, the fitting uncertainty of the small axis drops by more than a third because of the lower sub-Earth latitude afforded in 2003 (-28°) compared to 2008 (+47°), and the triaxial ellipsoid diameters become 218x175x129 km with fitting uncertainties of 3x3x14 km. We have estimated the systematic uncertainty of our method to be 4.1, 2.7, and 3.8%, respectively, for the three diameters. These values were recently derived (Drummond et al., in prep) from a comparison of KOALA (Carry et al, Planetary and Space Science 66, 200-212) and our triaxial ellipsoid analysis of four asteroids. Quadratically adding this systematic error with the fitting error, the total uncertainty for Metis becomes 9x5x15 km. Concurrently, we find an EQJ2000 rotational pole at [RA; Dec]=[185° +19°] or in ecliptic coordinates, [λ ; β ]=[176° +20°] (ECJ2000).

  15. Detecting Triaxiality in the Galactic Dark Matter Halo through Stellar Kinematics. II. Dependence on Nature of Dark Matter and Gravity

    NASA Astrophysics Data System (ADS)

    Rojas-Niño, Armando; Martínez-Medina, Luis A.; Pichardo, Barbara; Valenzuela, Octavio

    2015-05-01

    Recent studies have presented evidence that the Milky Way global potential may be non-spherical. In this case, the assembling process of the Galaxy may have left long-lasting stellar halo kinematic fossils due to the shape of the dark matter halo, potentially originated by orbital resonances. We further investigate such a possibility, now considering potential models further away from ΛCDM halos, like scalar field dark matter halos and Modified Newtonian Dynamics (MOND), and including several other factors that may mimic the emergence and permanence of kinematic groups, such as a spherical and triaxial halo with an embedded disk potential. We find that regardless of the density profile (DM nature), kinematic groups only appear in the presence of a triaxial halo potential. For the case of a MOND-like gravity theory no kinematic structure is present. We conclude that the detection of these kinematic stellar groups could confirm the predicted triaxiality of dark halos in cosmological galaxy formation scenarios.

  16. Silicon nanowire-based ring-shaped tri-axial force sensor for smart integration on guidewire

    NASA Astrophysics Data System (ADS)

    Han, Beibei; Yoon, Yong-Jin; Hamidullah, Muhammad; Tsu-Hui Lin, Angel; Park, Woo-Tae

    2014-06-01

    A ring-shaped tri-axial force sensor with a 200 µm × 200 µm sensor area using silicon nanowires (SiNWs) as piezoresistive sensing elements is developed and characterized. The sensor comprises a suspended ring structure located at the center of four suspended beams that can be integrated on the distal tip of a guidewire by passing through the hollow core of the sensor. SiNWs with a length of 6 µm and a cross section of 90 nm × 90 nm are embedded at the anchor of each silicon bridge along <1 1 0> direction as the piezoresistive sensing element. Finite element analysis has been used to determine the location of maximum stress and the simulation results are verified with the experimental measurements. Taking advantage of the high sensitivity of SiNWs, the fabricated ring-shaped sensor is capable of detecting small displacement in nanometer ranges with a sensitivity of 13.4 × 10-3 µm-1 in the z-direction. This tri-axial force sensor also shows high linearity (>99.9%) to the applied load and no obvious hysteresis is observed. The developed SiNW-based tri-axial force sensor provides new opportunities to implement sensing capability on medical instruments such as guidewires and robotic surgical grippers, where ultra-miniaturization and high sensitivity are essential.

  17. Two-dimensional imaging of Debye-Scherrer ring for tri-axial stress analysis of industrial materials

    NASA Astrophysics Data System (ADS)

    Sasaki, T.; Maruyama, Y.; Ohba, H.; Ejiri, S.

    2014-07-01

    In this study, an application of the two-dimensional imaging technology to the X ray tri-axial stress analysis was studied. An image plate (IP) was used to obtain a Debye-Scherre ring and the image data was analized for determining stress. A new principle for stress analysis which is suitable to two-dimensional imaging data was used. For the verification of this two-dimensional imaging type X-ray stress measurement method, an experiment was conducted using a ferritic steel sample which was processed with a surface grinder. Tri-axial stress analysis was conducted to evaluate the sample. The conventional method for X-ray tri-axial stress analysis proposed by Dölle and Hauk was used to evaluate residual stress in order to compare with the present method. As a result, it was confirmed that a sufficiently highly precise and high-speed stress measurement was enabled with the two-dimensional imaging technology compared with the conventional method.

  18. Effects of preform architecture on modulus and strength of 2-D triaxially braided textile composites

    NASA Technical Reports Server (NTRS)

    Masters, John E.; Naik, Rajiv; Minguet, Pierre J.

    1995-01-01

    Laminates formed using braided fibrous preforms have been extensively investigated during the course of the past few years as alternatives to unidirectional prepreg tape systems. This paper focused on one aspect of that work. It defined the role of the fibrous preform architecture in controlling a laminate's mechanical properties. The presentation was divided into four sections as the outline listed above illustrates. The presentation began with a brief introduction which defined the objectives of the study and detailed the materials studied. This was followed by a review of empirical test results. The materials' moduli and strengths were measured in both tension and compression. Their shear moduli were also experimentally determined. The review of the empirical data comprised the bulk of the presentation. A comparison of the experimental data to results predicted analytically was then presented. The presentation concluded with a few summary remarks. The specimens studied in this investigation featured 2-D triaxially braided AS4 graphite fiber preforms impregnated with Shell 1895 epoxy resin.

  19. Insights into Nuclear Triaxiality from Interference Effects in E2 Matrix Elements

    NASA Astrophysics Data System (ADS)

    Allmond, J. M.; Wood, J. L.; Kulp, W. D.

    2007-10-01

    Recently, we have introduced [1] a triaxial rotor model with independent inertia and E2 tensors. The E2 matrix elements [2] of the osmium isotopes (186, 188, 190, and 192) are studied in the framework of this model (59 of 84 E2 matrix elements deviate by 30% or less). It is shown that interference effects in the inertia tensor (K-mixing) and the E2 tensor can lead to significant reductions in the diagonal E2 matrix elements. In some instances, the diagonal E2 matrix elements may decrease with increasing spin. Additionally, a sum rule for diagonal E2 matrix elements is shown and used to explore missing strength from K-admixtures. [1] J.L. Wood, A-M. Oros-Peusquens, R. Zaballa, J.M. Allmond, and W.D. Kulp, Phys. Rev. C 70, 024308 (2004). [2] C.Y. Wu, D. Cline, T. Czosnyka, A. Backlin, C. Baktash, R.M. Diamond, G.D. Dracoulis, L. Hasselgren, H. Kluge, et al., Nucl. Phys. A607, 178 (1996).

  20. Gallery of Melt Textures Developed in Westerly Granite During High-Pressure Triaxial Friction Experiments

    USGS Publications Warehouse

    Moore, Diane E.; Lockner, David A.; Kilgore, Brian D.; Beeler, Nicholas M.

    2016-09-23

    IntroductionMelting occurred during stick-slip faulting of granite blocks sheared at room-dry, room-temperature conditions in a triaxial apparatus at 200–400 megapascals (MPa) confining pressure. Petrographic examinations of melt textures focused largely on the 400-MPa run products. This report presents an overview of the petrographic data collected on those samples, followed by brief descriptions of annotated versions of all the images.Scanning electron microscope (SEM) images of the starting materials and the three examined 400-MPa samples are presented in this report. Secondary-electron (SE) and backscattered-electron (BSE) imaging techniques were used on different samples. The SE images look down on the sawcut surfaces, yielding topographic and three-dimensional textural information. The BSE imaging was done on samples cut to provide cross-sectional views of the glass-filled shear band (or zone) that developed along the sawcut. Brightness in the BSE images increases with increasing mean atomic number of the material. Additional chemical information about the quenched melt and adjoining minerals was obtained using the energy dispersive system of the SEM during BSE examinations. However, the very narrow shear-band thicknesses and common occurrence of very fine lamellar compositional layering limited the usefulness of this technique for estimating melt chemistry.

  1. A new code for orbit analysis and Schwarzschild modelling of triaxial stellar systems

    NASA Astrophysics Data System (ADS)

    Vasiliev, Eugene

    2013-10-01

    We review the methods used to study the orbital structure and chaotic properties of various galactic models and to construct self-consistent equilibrium solutions by Schwarzschild's orbit superposition technique. These methods are implemented in a new publicly available software tool, SMILE, which is intended to be a convenient and interactive instrument for studying a variety of 2D and 3D models, including arbitrary potentials represented by a basis-set expansion, a spherical-harmonic expansion with coefficients being smooth functions of radius (splines) or a set of fixed point masses. We also propose two new variants of Schwarzschild modelling, in which the density of each orbit is represented by the coefficients of the basis-set or spline spherical-harmonic expansion, and the orbit weights are assigned in such a way as to reproduce the coefficients of the underlying density model. We explore the accuracy of these general-purpose potential expansions and show that they may be efficiently used to approximate a wide range of analytic density models and serve as smooth representations of discrete particle sets (e.g. snapshots from an N-body simulation), for instance, for the purpose of orbit analysis of the snapshot. For the variants of Schwarzschild modelling, we use two test cases - a triaxial Dehnen model containing a central black hole and a model re-created from an N-body snapshot obtained by a cold collapse. These tests demonstrate that all modelling approaches are capable of creating equilibrium models.

  2. Gallery of melt textures developed in Westerly Granite during high-pressure triaxial friction experiments

    USGS Publications Warehouse

    Moore, Diane E.; Lockner, David A.; Kilgore, Brian D.; Beeler, Nicholas M.

    2016-09-23

    IntroductionMelting occurred during stick-slip faulting of granite blocks sheared at room-dry, room-temperature conditions in a triaxial apparatus at 200–400 megapascals (MPa) confining pressure. Petrographic examinations of melt textures focused largely on the 400-MPa run products. This report presents an overview of the petrographic data collected on those samples, followed by brief descriptions of annotated versions of all the images.Scanning electron microscope (SEM) images of the starting materials and the three examined 400-MPa samples are presented in this report. Secondary-electron (SE) and backscattered-electron (BSE) imaging techniques were used on different samples. The SE images look down on the sawcut surfaces, yielding topographic and three-dimensional textural information. The BSE imaging was done on samples cut to provide cross-sectional views of the glass-filled shear band (or zone) that developed along the sawcut. Brightness in the BSE images increases with increasing mean atomic number of the material. Additional chemical information about the quenched melt and adjoining minerals was obtained using the energy dispersive system of the SEM during BSE examinations. However, the very narrow shear-band thicknesses and common occurrence of very fine lamellar compositional layering limited the usefulness of this technique for estimating melt chemistry.

  3. Tri-axial telecoil hearing aid for improved connection to public induction loops.

    PubMed

    Riehle, Timothy H; Knuesel, Robert J; Lichter, Patrick A; Panescu, Dorin

    2015-01-01

    Telecoils in hearing aids serve a dual purpose: to enhance telephone conversation and enable hearing aids to serve as a wireless interface for public audio broadcasts. When broadcasting audio signals, the signal is transmitted to the telecoil sensor (a magnetic field sensor located in the hearing aid) via magnetic energy from an induction wire loop located near the listener. This induction loop can be a small assembly located in the handset of the telephone or a large wire loop within a public venue like a theatre. Current hearing aids detect the magnetic signal using a single telecoil. If the telecoil is not aligned with the magnetic field, the strength of the detected signal is diminished. Unfortunately, public induction loops and telephone handsets seldom share a common alignment to the hearing aid, leading to sub-optimal performance by one or both in hearing aids available today. In this research, a prototype behind-the-ear (BTE) hearing aid with tri-axial telecoils was developed and DSP algorithms to process and combine the three signals were developed. The resulting hearing aid was evaluated in a human trial and provided better performance than a similar quality conventional telecoil hearing aid.

  4. Variation in deformation properties of processed MSWI bottom ash: results from triaxial tests.

    PubMed

    Arm, Maria

    2004-01-01

    This study is part of a larger study of the mechanical properties of processed municipal solid waste incinerator bottom ash. The aim was to investigate the variation in deformation properties of the ash for future use in unbound road layers. The effect of the material variation was analysed in particular. Specimens of bottom ash from four different incinerator plants and four sampling periods over a period of one year were tested by means of cyclic load triaxial tests. The results showed that there were variations in the deformation properties of the materials. Although there were significant differences between incinerator plants, the seasonal fluctuations were not significant. The differences were mainly due to the organic matter content. For the cyclic stress levels used, the resilient modulus ranged between 60 and 140 MPa, which is comparable to that of sand, but the plastic/permanent deformation was lower than for sand. It was also shown that the organic content has a limiting effect on the resilient modulus. For the material studied, the resilient modulus increased by 50% when the content of organic matter was halved. PMID:15567668

  5. Evaluation of Test Methods for Triaxially Braided Composites using a Meso-Scale Finite Element Model

    SciTech Connect

    Zhang, Chao

    2015-10-01

    The characterization of triaxially braided composite is complicate due to the nonuniformity of deformation within the unit cell as well as the possibility of the freeedge effect related to the large size of the unit cell. Extensive experimental investigation has been conducted to develop more accurate test approaches in characterizing the actual mechanical properties of the material we are studying. In this work, a meso-scale finite element model is utilized to simulate two complex specimens: notched tensile specimen and tube tensile specimen, which are designed to avoid the free-edge effect and free-edge effect induced premature edge damage. The full field strain data is predicted numerically and compared with experimental data obtained by Digit Image Correlation. The numerically predicted tensile strength values are compared with experimentally measured results. The discrepancy between numerically predicted and experimentally measured data, the capability of different test approaches are analyzed and discussed. The presented numerical model could serve as assistance to the evaluation of different test methods, and is especially useful in identifying potential local damage events.

  6. Triaxial rotor model description of E2 properties in {sup 186,188,190,192}Os

    SciTech Connect

    Allmond, J. M.; Zaballa, R.; Oros-Peusquens, A. M.; Kulp, W. D.; Wood, J. L.

    2008-07-15

    The triaxial rotor model with independent inertia and electric quadrupole tensors is applied to the description of the extensive set of E2 matrix elements available for {sup 186,188,190,192}Os. Most large and medium transition E2 matrix elements can be reproduced to within {approx}10%, and most diagonal elements to within {approx}30%. Most small transition matrix elements can be reproduced to within {approx}30%, and they support the interference effect exhibited by the model between the inertia and E2 tensors: this is a new feature of quantum rotor models. The diagonal E2 matrix elements at higher spins in the K=2 band are extremely sensitive to admixtures of higher K values: the low experimental values in {sup 190,192}Os indicate significant admixtures of K=4 components. Attention is given to the K{sup {pi}}=4{sup +} bands in these nuclei and the controversial issue of whether they are of quadrupole or hexadecapole nature.

  7. A laboratory study on the MSW mechanical behavior in triaxial apparatus.

    PubMed

    Karimpour-Fard, Mehran; Machado, Sandro Lemos; Shariatmadari, Nader; Noorzad, Ali

    2011-08-01

    Shear strength characterization of MSW materials is a mandatory task when performing analyses related to landfill design and landfill geometry improvements. Despite the considerable amount of research focusing on MSW mechanical behavior there remain certain aspects which are not completely understood and deserve attention in particular the case of the undrained behavior of MSW. This paper presents the results of a comprehensive laboratory testing program using a large-scale triaxial apparatus at the Federal University of Bahia, Salvador, Brazil. The effect of factors such as confining pressure, unit weight, fiber content, rate of loading and over-consolidation on the MSW mechanical response were investigated. Tested samples presented typical MSW shear/strain curves (concave upward) in all the tests, despite the pore water pressure reaching levels almost equal to the confining pressure. The obtained results show that increasing confining stress, unit weight, loading rate, fiber content and over-consolidation lead to an increase in the MSW shear strength. The importance of the fibrous components in the waste behavior is highlighted and graphs showing the variation of the MSW shear strength with fiber content in different drainage conditions are shown. The authors believe these results could be of interest to many companies, especially considering the new trend of plastic material recycling (prior landfilling) for energy recovery purposes. PMID:21478006

  8. Extremely Low-Stress Triaxiality Tests in Calibration of Fracture Models in Metal-Cutting Simulation

    NASA Astrophysics Data System (ADS)

    Šebek, František; Kubík, Petr; Petruška, Jindřich; Hůlka, Jiří

    2016-04-01

    The cutting process is now combined with machining, milling, or drilling as one of the widespread manufacturing operations. It is used across various fields of engineering. From an economical point of view, it is desirable to maintain the process in the most effective way in terms of the fracture surface quality or minimizing the burr. It is not possible to manage this experimentally in mass production. Therefore, it is convenient to use numerical computation. To include the crack initiation and propagation in the computations, it is necessary to implement a suitable ductile fracture criterion. Uncoupled ductile fracture models need to be calibrated first from fracture tests when the test selection is crucial. In the present article, there were selected widespread uncoupled ductile fracture models calibrated with, among others, an extremely low-stress triaxiality test realized through the compression of a cylinder with a specific recess. The whole experimental program together with the cutting process experiment were carried out on AISI 1045 carbon steel. After the fracture models were calibrated and the cutting process was simulated with their use, fracture surfaces and force responses from computations were compared with those experimentally obtained and concluding remarks were made.

  9. Mechanical behavior of a triaxially braided textile composite at high temperature

    NASA Astrophysics Data System (ADS)

    El Mourid, Amine

    The work presented in this thesis aimed at understanding the influence of viscoelasticity, temperature and aging on the mechanical behaviour of a textile composite using experimental, analytical and numerical tools. The studied material was a triaxially braided composite with fibres in the 0°/+/-60° directions. The yarns were made of carbon fibres, embedded in an MVK10 temperature resistant polyimide matrix. The first step consisted in developing analytical and numerical frameworks to predict viscoelastic behaviour in textile composites. Simulations were performed for both braided and woven textile architectures, at different stiffness contrasts and yarns volume fractions. The analytical framework accuracy was verified with the help of the numerical simulations. An important finding of this study was that the analytical framework, combined with the Mori-Tanaka model, leads to relatively accurate predictions for both the permanent and transient parts. Therefore, the authors believe that the Mori-Tanaka model with an adjusted aspect ratio to take into account yarn curvature is reliable for predicting viscoelastic behaviour in textile composites. The textile composite that was studied in this project did not display viscoelastic behaviour, due to the high yarn volume fraction. However, the framework remains relevant for higher temperature applications or lower yarn volume fractions. The second step was to investigate the temperature effect on the tensile behavior of the carbon/MVK10 triaxially braided composite material studied in this project. To achieve this goal, a series of room and high temperature tensile tests on both matrix and composite samples were performed. The tests on composite samples were performed along two different material directions at the maximum service temperature allowed by the Federal Aviation Administration for aircraft components, and a dedicated replication technique was developed in order to track crack densities as a function of

  10. Extremely Low-Stress Triaxiality Tests in Calibration of Fracture Models in Metal-Cutting Simulation

    NASA Astrophysics Data System (ADS)

    Šebek, František; Kubík, Petr; Petruška, Jindřich; Hůlka, Jiří

    2016-11-01

    The cutting process is now combined with machining, milling, or drilling as one of the widespread manufacturing operations. It is used across various fields of engineering. From an economical point of view, it is desirable to maintain the process in the most effective way in terms of the fracture surface quality or minimizing the burr. It is not possible to manage this experimentally in mass production. Therefore, it is convenient to use numerical computation. To include the crack initiation and propagation in the computations, it is necessary to implement a suitable ductile fracture criterion. Uncoupled ductile fracture models need to be calibrated first from fracture tests when the test selection is crucial. In the present article, there were selected widespread uncoupled ductile fracture models calibrated with, among others, an extremely low-stress triaxiality test realized through the compression of a cylinder with a specific recess. The whole experimental program together with the cutting process experiment were carried out on AISI 1045 carbon steel. After the fracture models were calibrated and the cutting process was simulated with their use, fracture surfaces and force responses from computations were compared with those experimentally obtained and concluding remarks were made.

  11. Characterization of Biaxial and Triaxial Braids: Fiber Architecture and Mechanical Properties

    NASA Astrophysics Data System (ADS)

    Birkefeld, Karin; Röder, Mirko; von Reden, Tjark; Bulat, Martina; Drechsler, Klaus

    2012-06-01

    Biaxial and triaxial carbon fiber braids with off-axis braiding angles of 30°, 45° and 55° are characterized with respect to their fiber architecture. All braids are produced on a round mandrel with constant cross section. Detailed geometric information on the different braids, like roving dimensions, roving shapes and the degree of nesting is given. The findings from measurements in photomicrographs are used to construct meso-model yarn architectures at the unit cell level which are then analyzed with the WiseTex software (Lomov et al. Compos. Sci. Technol. 60:2083-2095, 2000). The results of the models' analysis with TexComp and comparison of mechanical properties with tests are consistent and essential for further steps in predictive modeling. Predictive modeling was also performed for biaxial braids based on the packing density in the material and parameters of the braiding process. The good conformance of the predictive models gives a validated starting point for development of braided structures concerning stiffness behavior. In addition, the information about the fiber architecture can be used for failure analysis on unit cell level.

  12. Effect of Microscopic Damage Events on Static and Ballistic Impact Strength of Triaxial Braid Composites

    NASA Technical Reports Server (NTRS)

    Littell, Justin D.; Binienda, Wieslaw K.; Arnold, William A.; Roberts, Gary D.; Goldberg, Robert K.

    2010-01-01

    The reliability of impact simulations for aircraft components made with triaxial-braided carbon-fiber composites is currently limited by inadequate material property data and lack of validated material models for analysis. Methods to characterize the material properties used in the analytical models from a systematically obtained set of test data are also lacking. A macroscopic finite element based analytical model to analyze the impact response of these materials has been developed. The stiffness and strength properties utilized in the material model are obtained from a set of quasi-static in-plane tension, compression and shear coupon level tests. Full-field optical strain measurement techniques are applied in the testing, and the results are used to help in characterizing the model. The unit cell of the braided composite is modeled as a series of shell elements, where each element is modeled as a laminated composite. The braided architecture can thus be approximated within the analytical model. The transient dynamic finite element code LS-DYNA is utilized to conduct the finite element simulations, and an internal LS-DYNA constitutive model is utilized in the analysis. Methods to obtain the stiffness and strength properties required by the constitutive model from the available test data are developed. Simulations of quasi-static coupon tests and impact tests of a represented braided composite are conducted. Overall, the developed method shows promise, but improvements that are needed in test and analysis methods for better predictive capability are examined.

  13. Proposed triaxial atomic force microscope contact-free tweezers for nanoassembly.

    PubMed

    Brown, Keith A; Westervelt, Robert M

    2009-09-23

    We propose a triaxial atomic force microscope contact-free tweezer (TACT) for the controlled assembly of nanoparticles suspended in a liquid. The TACT overcomes four major challenges faced in nanoassembly, as follows. (1) The TACT can hold and position a single nanoparticle with spatial accuracy smaller than the nanoparticle size (approximately 5 nm). (2) The nanoparticle is held away from the surface of the TACT by negative dielectrophoresis to prevent van der Waals forces from making it stick to the TACT. (3) The TACT holds nanoparticles in a trap that is size-matched to the particle and surrounded by a repulsive region so that it will only trap a single particle at a time. (4) The trap can hold a semiconductor nanoparticle in water with a trapping energy greater than the thermal energy. For example, a 5 nm radius silicon nanoparticle is held with 10 k(B)T at room temperature. We propose methods for using the TACT as a nanoscale pick-and-place tool to assemble semiconductor quantum dots, biological molecules, semiconductor nanowires, and carbon nanotubes.

  14. The triaxial particle plus rotor model and wobbling mode: A semiclassical view

    SciTech Connect

    Gupta, Rajiv; Malik, S. S.; Jain, A. K.; Jain, S. R.

    2010-11-24

    A systematic analysis of the triaxial particle rotor model with single-j shell configuration is carried out to explain the prominent features of observed wobbling excitations in odd A nuclei. The equations of motion for the angular momentum vectors I-vector and j-vector generate two types of equilibrium (i.e., (i) the axes aligned and (ii) the planar) states. The planar equilibrium states involve mainly the orientation degree of freedom {gamma} and their Jacobian matrix J gives purely imaginary eigenvalues in conjugate pairs. Also, our dynamical results show a substantial projection of angular momentum vectors on all the three principal axes, which implies that the resultant angular momentum lies outside the planes of three axes. Both these signatures confirm the spontaneous breakdown of time reversal (T) plus rotation by 180 deg. (R{sub {pi}}) i.e., R{sub {pi}T} symmetry and as a result nearly two identical bands consisting of even and odd spins emerge. We have tested our dynamical formalism for the wobbling mode observed in {sup 163}Lu.

  15. Triaxial Klystron for Efficient, Long-Pulse, High-Power Microwave Generation

    NASA Astrophysics Data System (ADS)

    Pasour, J. A.; Smithe, D.; Friedman, M.

    1998-11-01

    The Triaxial Klystron has intrinsic advantages over alternative klystron configurations. It consists of a thin annular electron beam propagating in an annular drift region, with cavity structures located inside and outside the beam. This geometry fundamentally alters the usual klystron frequency scaling, allowing the overall diameter to be increased to accommodate higher beam current and microwave power. Beam transport and stability are also enhanced by the division of image charges and return current between the inner and outer conductors. Initial X-band experiments at NRL have demonstrated stable beam transport (400 keV, 15 kA) and strong bunching. (M. Friedman, J. Pasour, and D. Smithe, Appl. Phys. Lett. 71, 3724 (1997).) MAGIC simulations of a 400-keV, 2-15 kA, 6-cm radius by 3-mm-thick annular beam show strong bunching at X-band and efficient (50%) energy extraction from a specially designed radial cavity structure. We will describe ongoing work to improve this non-optimized structure and to examine scaling to higher frequencies (up to 30 GHz). Efforts now underway at MRC to build a μs-duration version of this device will also be discussed.

  16. Implementation of a real-time human movement classifier using a triaxial accelerometer for ambulatory monitoring.

    PubMed

    Karantonis, Dean M; Narayanan, Michael R; Mathie, Merryn; Lovell, Nigel H; Celler, Branko G

    2006-01-01

    The real-time monitoring of human movement can provide valuable information regarding an individual's degree of functional ability and general level of activity. This paper presents the implementation of a real-time classification system for the types of human movement associated with the data acquired from a single, waist-mounted triaxial accelerometer unit. The major advance proposed by the system is to perform the vast majority of signal processing onboard the wearable unit using embedded intelligence. In this way, the system distinguishes between periods of activity and rest, recognizes the postural orientation of the wearer, detects events such as walking and falls, and provides an estimation of metabolic energy expenditure. A laboratory-based trial involving six subjects was undertaken, with results indicating an overall accuracy of 90.8% across a series of 12 tasks (283 tests) involving a variety of movements related to normal daily activities. Distinction between activity and rest was performed without error; recognition of postural orientation was carried out with 94.1% accuracy, classification of walking was achieved with less certainty (83.3% accuracy), and detection of possible falls was made with 95.6% accuracy. Results demonstrate the feasibility of implementing an accelerometry-based, real-time movement classifier using embedded intelligence.

  17. Hypertension during chronic exposure to cold: Comparison between Sprague Dawley (SD) and Long Evans (LE) strains

    SciTech Connect

    Riesselmann, A.; Baron, A.; Fregly, M.J. )

    1991-03-11

    Hypertension accompanies chronic exposure of SD rats to cold (5-6C), including elevation of systolic, diastolic, and mean blood pressures and cardiac hypertrophy. The renin-angiotensin system may play an important role. Earlier studies suggested that the LE strain may have a decrease in angiotensin I converting enzyme (ACE) activity. Measurement of ACE activity in plasmas of SE and LE strains revealed that basal activity of ACE in the plasma of the LE strain was significantly less than that of the SD strain. A second study was carried out in which both strains were exposed to cold for 7 weeks. There were clear differences between strains. Rats of the SD strain had a significant elevation in their blood pressure; a significantly increased urinary output of norepinephrine (NE) and epinephrine (E); and significant increases in weights of heart, kidneys, adrenals, and brown adipose tissue (IBAT) compared to their controls maintained at 26C. In contrast, rats of the LE strain were less responsive to cold in that blood pressure failed to rise as sharply and to attain as high a level; NE and E outputs, as well as weights of heart and IBAT were significantly less than those of rats of the cold-treated SD strain. Thus, the lower ACE activity in plasma of LE strain, as well as a reduced secretion of catecholamines, may protect these rats against the rise of blood pressure characteristically observed when rats of the SD strain are exposed to cold.

  18. Synthesis and size characterization of silica nanospheres using sedimentation field-flow fractionation (SdFFF).

    PubMed

    Kim, Woon Jung; Ahn, Se Young; Kim, Jai Hoon; Chun, Jong Han; Yu, Jong Shin; Jung, Euo Chang; Lee, Seungho

    2012-01-01

    Silica nanoparticles were synthesized by a conventional emulsion polymerization by mixing ethanol, ammonium hydroxide, water and tetra ethyl orthosilicate (TEOS). A new reaction apparatus was assembled for a large scale synthesis of silica nanospheres in the laboratory, which was designed for uniform mixing of the reactants. The apparatus was equipped with a disc type agitator with six rectangular propellers. The new apparatus allowed high reproducibility in terms of the mean size and the size distribution of the silica nanoparticles with the relative standard deviation of less than about 6%. Sedimentation field-flow fractionation (SdFFF) was employed for determination of the size distribution of the silica nanoparticles. SdFFF provided size-based separation of the silica nanoparticles, with the retention time increasing with the size. When SdFFF analysis was repeated three times for the same sample, the standard deviation was less than 4%, showing reliability of SdFFF in size measurement. SdFFF seems to provide more accurate size distribution than DLS, particularly for those having broad and multimodal size distributions. Change in the agitation speed resulted in significant change in the mean diameter of the silica nanoparticles. Agitation speed of 400 rpm in 3 L reaction vessel yielded silica particles of about 100 nm in diameter, while at 200 rpm in 1 L vessel yielded those of about 500 nm. PMID:22524028

  19. Characterization of Two Segregation Distorter Revertants: Evidence That the Tandem Duplication Is Necessary for Sd Activity in Drosophila Melanogaster

    PubMed Central

    Palopoli, M. F.; Doshi, P.; Wu, C. I.

    1994-01-01

    Segregation Distorter (SD) is a naturally occurring system of meiotic drive in Drosophila melanogaster. Males heterozygous for an SD second chromosome and a normal homolog (SD(+)) transmit predominantly SD-bearing sperm. To accomplish this, the Segregation distorter (Sd) locus induces the dysfunction of those spermatids that receive the SD(+) chromosome. Recently, P. A. Powers and B. Ganetzky isolated overlapping DNA clones spanning the region of DNA known to contain the Sd gene and identified a 5-kb tandem duplication that is present on all SD chromosomes examined, but is apparently absent from wild-type chromosomes. Here we report a molecular analysis of two spontaneous revertants from an Australian SD chromosome (SD-Arm28). Both of these revertants have lost the 5-kb tandem duplication along with the ability to distort transmission; the critical observation, however, is that they retain the DNA haplotype in the flanking regions (both proximally and distally) that is characteristic of the original SD-Arm28. We propose unequal sister chromatid exchange between the tandem repeats as the only plausible explanation for loss of a repeat while retaining flanking markers. This provides direct evidence that the tandem duplication is indeed necessary for the Sd phenotype. Further, we examined testes-specific levels of both RNA and protein for the nearby Topoisomerase 2 gene. Neither revealed a consistent difference between SD and SD(+) strains. We also measured testes-specific levels of RNA using the tandem duplication itself as probe. Our results suggest that there is strong up-regulation of one or several 2.0-2.3-kb transcripts from the duplicated region in the testes of an SD strain. Whether it is this overexpression of transcripts that causes segregation distortion remains to be investigated. PMID:8138158

  20. Hydromechanical Behaviour of Unconsolidated Granular Materials under Proportional Triaxial Compression Tests

    NASA Astrophysics Data System (ADS)

    Nguyen, V.; Gland, N. F.; Dautriat, J.; Guelard, J.; David, C.

    2010-12-01

    During the production of petroleum reservoirs, compaction due to depletion (pore fluid pressure reduction) can lead to emphasis of natural permeability anisotropy and significant permeability reduction. Under such effective stress increase, weakly consolidated reservoirs will undergo strong deformation inducing important modifications of the transport properties, which control the fluid flows in the reservoir and the productivity of the wells. Classically the mechanical loadings applied in the laboratory are either hydrostatic or deviatoric at constant confining pressure; however the 'in-situ' stress paths experienced by the reservoirs differ; it is thus important to perform loading tests with more appropriate conditions such as ‘proportional triaxial’ and ‘oedometric’. This study focuses on the elastoplatic behaviour of non to weakly consolidated reservoir rocks (analogues) and the influence of the stress path (K=ΔσH/ΔσV) on the evolutions of porosity and permeability. Generally, permeability of pourous rocks evolves in three stages: (1) initial decrease related to compaction (soft rocks) or closing of pre-existing microflaws (compact rocks), (2) small reduction associated to the 'linear' deformation regime, (3) drop due to a strong compaction linked to porosity collapse and grain crushing mechanisms. The intensity of this reduction depends on the stress path coefficient, the grain sharpness and the granular texture. We use a triaxial cell (maximum axial load of 80kN and maximum confinement of 69MPa) to perform proportional triaxial compression tests (0

  1. A New sdO+dM Binary with Extreme Eclipses and Reflection Effect

    NASA Astrophysics Data System (ADS)

    Derekas, A.; Németh, P.; Southworth, J.; Borkovits, T.; Sárneczky, K.; Pál, A.; Csák, B.; Garcia-Alvarez, D.; Maxted, P. F. L.; Kiss, L. L.; Vida, K.; Szabó, Gy. M.; Kriskovics, L.

    2015-08-01

    We report the discovery of a new totally eclipsing binary (R.A. = {06}{{h}}{40}{{m}}{29}{{s}}11; decl. = +38°56‧52″2 J = 2000.0; Rmax = 17.2 mag) with an sdO primary and a strongly irradiated red dwarf companion. It has an orbital period of Porb = 0.187284394(11) day and an optical eclipse depth in excess of 5 mag. We obtained 2 low-resolution classification spectra with GTC/OSIRIS and 10 medium-resolution spectra with WHT/ISIS to constrain the properties of the binary members. The spectra are dominated by H Balmer and He ii absorption lines from the sdO star, and phase-dependent emission lines from the irradiated companion. A combined spectroscopic and light curve analysis implies a hot subdwarf temperature of Teff(spec) = 55,000 ± 3000 K, surface gravity of log g (phot) = 6.2 ± 0.04 (cgs), and a He abundance of {log}(n{He}/n{{H}})=-2.24+/- 0.40. The hot sdO star irradiates the red dwarf companion, heating its substellar point to about 22,500 K. Surface parameters for the companion are difficult to constrain from the currently available data: the most remarkable features are the strong H Balmer and C ii-iii lines in emission. Radial velocity estimates are consistent with the sdO+dM classification. The photometric data do not show any indication of sdO pulsations with amplitudes greater than 7 mmag, and Hα-filter images do not provide evidence for the presence of a planetary nebula associated with the sdO star.

  2. Assessing head and trunk symmetry during sleep using tri-axial accelerometers.

    PubMed

    Sato, Haruhiko; Ikura, Daiki; Tsunoda, Masahiro

    2015-03-01

    Using two types of small, lightweight tri-axial accelerometers, we obtained evidence for the effectiveness of an approach for assessing head-trunk symmetrical or asymmetrical positions during sleep. First, we assessed the accuracy of our monitoring system in five healthy young adults (age range, 22-24 years). The participants wore acceleration monitors on the sternum and forehead; then spent 5 min in six different positions. Once accuracy was confirmed, we assessed head-trunk symmetry during night-time sleep in 10 healthy children (age range, 3-13 years) and 10 young adults (age range, 21-26 years) in their home environments. All participants wore the monitors during one night's sleep in their homes. After computing head-trunk positions using the orientation data obtained by the accelerometers, head and trunk symmetry were evaluated. The head and trunk positions were correctly detected: the positional data from the trunk had 99% agreement, and the data from the head had 96% agreement. Both the young adults and children were observed to spend time with the head-trunk in asymmetric positions; however, the subjects changed position frequently so the asymmetrical postures were mobile. We concluded that the proposed monitoring system is a reliable and valid approach for assessing head-trunk symmetry during sleep at home. Implications for Rehabilitation We propose a head and trunk symmetry monitoring system using accelerometers. The proposed system could accurately identify head and trunk position. Asymmetrical positioning was seen in healthy participants but it was not immobile. PMID:24274623

  3. Drained response of municipal solid waste in large-scale triaxial shear testing.

    PubMed

    Zekkos, Dimitrios; Bray, Jonathan D; Riemer, Michael F

    2012-10-01

    A comprehensive laboratory investigation was performed on municipal solid waste (MSW) from a landfill located in northern California using a large-scale triaxial (TX) apparatus. An improved, standardized waste specimen preparation method was developed and used to prepare 27 large-scale TX specimens (d=300 mm, h=600-630 mm). The effects of waste composition, confining stress, unit weight, loading rate, and stress path on the drained stress-strain response of MSW were investigated. Waste composition has a significant effect on its stress-strain response. The commonly observed upward curvature of the stress-strain response of specimens composed of larger-sized waste materials results from the fibrous constituents (primarily paper, plastic and wood) reinforcing the waste matrix. This effect is greatest when the MSW specimen is sheared across the long axis of the fibrous particles. Due to this significant strain hardening effect and waste's in situ stress state, a limiting strain failure criterion of 5% axial strain from the K(o) field consolidation state is judged to be most appropriate. Results from this test program and data from the literature indicate that the TX compression secant friction angle of MSW varies from 34° to 44°, with 39° as a best estimate, at a confining stress of one atmosphere (assuming c=0). The friction angle decreases as confining stress increases. The friction angles measured in this testing program are representative of failure surfaces that are oriented at an angle to the predominant orientation of the long axis of the fibrous waste particles. These friction angles are higher than those obtained in direct shear tests where shearing typically occurs parallel to the orientation of the fibrous waste particles. PMID:22704000

  4. Physical activity levels in three Brazilian birth cohorts as assessed with raw triaxial wrist accelerometry

    PubMed Central

    da Silva, Inácio CM; van Hees, Vincent T; Ramires, Virgílio V; Knuth, Alan G; Bielemann, Renata M; Ekelund, Ulf; Brage, Soren; Hallal, Pedro C

    2014-01-01

    Background: Data on objectively measured physical activity are lacking in low- and middle-income countries. The aim of this study was to describe objectively measured overall physical activity and time spent in moderate-to-vigorous physical activity (MVPA) in individuals from the Pelotas (Brazil) birth cohorts, according to weight status, socioeconomic status (SES) and sex. Methods: All children born in 1982, 1993 and 2004 in hospitals in the city of Pelotas, Brazil, constitute the sampling frame; of these 99% agreed to participate. The most recent follow-ups were conducted between 2010 and 2013. In total, 8974 individuals provided valid data derived from raw triaxial wrist accelerometry. The average acceleration is presented in milli-g (1 mg = 0.001g), and time (min/d) spent in MVPA (>100 mg) is presented in 5- and 10-min bouts. Results: Mean acceleration in the 1982 (mean age 30.2 years), 1993 (mean age 18.4 years) and 2004 (mean age 6.7 years) cohorts was 35 mg, 39 mg and 60 mg, respectively. Time spent in MVPA was 26 [95% confidence interval (CI) 25; 27], 43 (95% CI 42; 44) and 45 (95% CI 43; 46) min/d in the three cohorts, respectively, using 10-min bouts. Mean MVPA was on average 42% higher when using 5-min bouts. Males were more active than females and physical activity was inversely associated with age of the cohort and SES. Normal-weight individuals were more active than underweight, overweight and obese participants. Conclusions: Overall physical activity and time spent in MVPA differed by cohort (age), sex, weight status and SES. Higher levels of activity in low SES groups may be explained by incidental physical activity. PMID:25361583

  5. Assessing head and trunk symmetry during sleep using tri-axial accelerometers.

    PubMed

    Sato, Haruhiko; Ikura, Daiki; Tsunoda, Masahiro

    2015-03-01

    Using two types of small, lightweight tri-axial accelerometers, we obtained evidence for the effectiveness of an approach for assessing head-trunk symmetrical or asymmetrical positions during sleep. First, we assessed the accuracy of our monitoring system in five healthy young adults (age range, 22-24 years). The participants wore acceleration monitors on the sternum and forehead; then spent 5 min in six different positions. Once accuracy was confirmed, we assessed head-trunk symmetry during night-time sleep in 10 healthy children (age range, 3-13 years) and 10 young adults (age range, 21-26 years) in their home environments. All participants wore the monitors during one night's sleep in their homes. After computing head-trunk positions using the orientation data obtained by the accelerometers, head and trunk symmetry were evaluated. The head and trunk positions were correctly detected: the positional data from the trunk had 99% agreement, and the data from the head had 96% agreement. Both the young adults and children were observed to spend time with the head-trunk in asymmetric positions; however, the subjects changed position frequently so the asymmetrical postures were mobile. We concluded that the proposed monitoring system is a reliable and valid approach for assessing head-trunk symmetry during sleep at home. Implications for Rehabilitation We propose a head and trunk symmetry monitoring system using accelerometers. The proposed system could accurately identify head and trunk position. Asymmetrical positioning was seen in healthy participants but it was not immobile.

  6. In-shoe plantar tri-axial stress profiles during maximum-effort cutting maneuvers.

    PubMed

    Cong, Yan; Lam, Wing Kai; Cheung, Jason Tak-Man; Zhang, Ming

    2014-12-18

    Soft tissue injuries, such as anterior cruciate ligament rupture, ankle sprain and foot skin problems, frequently occur during cutting maneuvers. These injuries are often regarded as associated with abnormal joint torque and interfacial friction caused by excessive external and in-shoe shear forces. This study simultaneously investigated the dynamic in-shoe localized plantar pressure and shear stress during lateral shuffling and 45° sidestep cutting maneuvers. Tri-axial force transducers were affixed at the first and second metatarsal heads, lateral forefoot, and heel regions in the midsole of a basketball shoe. Seventeen basketball players executed both cutting maneuvers with maximum efforts. Lateral shuffling cutting had a larger mediolateral braking force than 45° sidestep cutting. This large braking force was concentrated at the first metatarsal head, as indicated by its maximum medial shear stress (312.2 ± 157.0 kPa). During propulsion phase, peak shear stress occurred at the second metatarsal head (271.3 ± 124.3 kPa). Compared with lateral shuffling cutting, 45° sidestep cutting produced larger peak propulsion shear stress (463.0 ± 272.6 kPa) but smaller peak braking shear stress (184.8 ± 181.7 kPa), of which both were found at the first metatarsal head. During both cutting maneuvers, maximum medial and posterior shear stress occurred at the first metatarsal head, whereas maximum pressure occurred at the second metatarsal head. The first and second metatarsal heads sustained relatively high pressure and shear stress and were expected to be susceptible to plantar tissue discomfort or injury. Due to different stress distribution, distinct pressure and shear cushioning mechanisms in basketball footwear might be considered over different foot regions.

  7. Epoxy encapsulation of the Cernox™ SD thermometer for measuring the temperature of surfaces in liquid helium

    NASA Astrophysics Data System (ADS)

    Dhuley, R. C.; Van Sciver, S. W.

    2016-07-01

    We describe a procedure to pot a Cernox™ thermometer with the SD package in Stycast epoxy. The potting adapts the thermometer for measuring the temperature of a surface immersed in liquid helium (LHe) and other cryogens. The technique thermally insulates the sensor chip from the cryogen while preserving the surface mounting capability of the SD package. The potting introduced <1% shift in the resistance, <0.5% shift in the calibration at 4.2 K and 77 K, and provided repeatable measurements during thermal cycles between room temperature and 4.2 K.

  8. Initial results from the Solar Dynamic (SD) Ground Test Demonstration (GTD) project at NASA Lewis

    NASA Technical Reports Server (NTRS)

    Shaltens, Richard K.; Boyle, Robert V.

    1995-01-01

    A government/industry team designed, built, and tested a 2 kWe solar dynamic space power system in a large thermal/vacuum facility with a simulated sun at the NASA Lewis Research Center. The Lewis facility provides an accurate simulation of temperatures, high vacuum, and solar flux as encountered in low earth orbit. This paper reviews the goals and status of the Solar Dynamic (SD) Ground Test Demonstration (GTD) program and describes the initial testing, including both operational and performance data. This SD technology has the potential as a future power source for the International Space Station Alpha.

  9. Shell-model study for neutron-rich sd-shell nuclei

    SciTech Connect

    Kaneko, Kazunari; Sun Yang; Mizusaki, Takahiro; Hasegawa, Munetake

    2011-01-15

    The microscopic structure of neutron-rich sd-shell nuclei is investigated by using the spherical-shell model in the sd-pf valence space with the extended pairing plus quadrupole-quadrupole forces accompanied by the monopole interaction (EPQQM). The calculation reproduces systematically the known energy levels for even-even and odd-mass nuclei including the recent data for {sup 43}S, {sup 46}S, and {sup 47}Ar. In particular, the erosion of the N=28 shell closure in {sup 42}Si can be explained. Our EPQQM results are compared with other shell-model calculations with the SDPF-NR and SDPF-U effective interactions.

  10. Pore-water extraction from unsaturated tuff by triaxial and one-dimensional compression methods, Nevada Test Site, Nevada

    USGS Publications Warehouse

    Mower, Timothy E.; Higgins, Jerry D.; Yang, In C.; Peters, Charles A.

    1994-01-01

    Study of the hydrologic system at Yucca Mountain, Nevada, requires the extraction of pore-water samples from welded and nonwelded, unsaturated tuffs. Two compression methods (triaxial compression and one-dimensional compression) were examined to develop a repeatable extraction technique and to investigate the effects of the extraction method on the original pore-fluid composition. A commercially available triaxial cell was modified to collect pore water expelled from tuff cores. The triaxial cell applied a maximum axial stress of 193 MPa and a maximum confining stress of 68 MPa. Results obtained from triaxial compression testing indicated that pore-water samples could be obtained from nonwelded tuff cores that had initial moisture contents as small as 13 percent (by weight of dry soil). Injection of nitrogen gas while the test core was held at the maximum axial stress caused expulsion of additional pore water and reduced the required initial moisture content from 13 to 11 percent. Experimental calculations, together with experience gained from testing moderately welded tuff cores, indicated that the triaxial cell used in this study could not apply adequate axial or confining stress to expel pore water from cores of densely welded tuffs. This concern led to the design, fabrication, and testing of a one-dimensional compression cell. The one-dimensional compression cell used in this study was constructed from hardened 4340-alloy and nickel-alloy steels and could apply a maximum axial stress of 552 MPa. The major components of the device include a corpus ring and sample sleeve to confine the sample, a piston and base platen to apply axial load, and drainage plates to transmit expelled water from the test core out of the cell. One-dimensional compression extracted pore water from nonwelded tuff cores that had initial moisture contents as small as 7.6 percent; pore water was expelled from densely welded tuff cores that had initial moisture contents as small as 7

  11. Wireless Tri-Axial Trunk Accelerometry Detects Deviations in Dynamic Center of Mass Motion Due to Running-Induced Fatigue

    PubMed Central

    2015-01-01

    Small wireless trunk accelerometers have become a popular approach to unobtrusively quantify human locomotion and provide insights into both gait rehabilitation and sports performance. However, limited evidence exists as to which trunk accelerometry measures are suitable for the purpose of detecting movement compensations while running, and specifically in response to fatigue. The aim of this study was therefore to detect deviations in the dynamic center of mass (CoM) motion due to running-induced fatigue using tri-axial trunk accelerometry. Twenty runners aged 18–25 years completed an indoor treadmill running protocol to volitional exhaustion at speeds equivalent to their 3.2 km time trial performance. The following dependent measures were extracted from tri-axial trunk accelerations of 20 running steps before and after the treadmill fatigue protocol: the tri-axial ratio of acceleration root mean square (RMS) to the resultant vector RMS, step and stride regularity (autocorrelation procedure), and sample entropy. Running-induced fatigue increased mediolateral and anteroposterior ratios of acceleration RMS (p < .05), decreased the anteroposterior step regularity (p < .05), and increased the anteroposterior sample entropy (p < .05) of trunk accelerometry patterns. Our findings indicate that treadmill running-induced fatigue might reveal itself in a greater contribution of variability in horizontal plane trunk accelerations, with anteroposterior trunk accelerations that are less regular from step-to-step and are less predictable. It appears that trunk accelerometry parameters can be used to detect deviations in dynamic CoM motion induced by treadmill running fatigue, yet it is unknown how robust or generalizable these parameters are to outdoor running environments. PMID:26517261

  12. Wireless Tri-Axial Trunk Accelerometry Detects Deviations in Dynamic Center of Mass Motion Due to Running-Induced Fatigue.

    PubMed

    Schütte, Kurt H; Maas, Ellen A; Exadaktylos, Vasileios; Berckmans, Daniel; Venter, Rachel E; Vanwanseele, Benedicte

    2015-01-01

    Small wireless trunk accelerometers have become a popular approach to unobtrusively quantify human locomotion and provide insights into both gait rehabilitation and sports performance. However, limited evidence exists as to which trunk accelerometry measures are suitable for the purpose of detecting movement compensations while running, and specifically in response to fatigue. The aim of this study was therefore to detect deviations in the dynamic center of mass (CoM) motion due to running-induced fatigue using tri-axial trunk accelerometry. Twenty runners aged 18-25 years completed an indoor treadmill running protocol to volitional exhaustion at speeds equivalent to their 3.2 km time trial performance. The following dependent measures were extracted from tri-axial trunk accelerations of 20 running steps before and after the treadmill fatigue protocol: the tri-axial ratio of acceleration root mean square (RMS) to the resultant vector RMS, step and stride regularity (autocorrelation procedure), and sample entropy. Running-induced fatigue increased mediolateral and anteroposterior ratios of acceleration RMS (p < .05), decreased the anteroposterior step regularity (p < .05), and increased the anteroposterior sample entropy (p < .05) of trunk accelerometry patterns. Our findings indicate that treadmill running-induced fatigue might reveal itself in a greater contribution of variability in horizontal plane trunk accelerations, with anteroposterior trunk accelerations that are less regular from step-to-step and are less predictable. It appears that trunk accelerometry parameters can be used to detect deviations in dynamic CoM motion induced by treadmill running fatigue, yet it is unknown how robust or generalizable these parameters are to outdoor running environments.

  13. 75 FR 426 - Notice of Application for Disclaimer of Interest, Brookings County, SD

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-05

    ... Bureau of Land Management Notice of Application for Disclaimer of Interest, Brookings County, SD AGENCY... Recordable Disclaimer of Interest from the United States for an easement in Brookings County, South Dakota... Recordable Disclaimer of Interest, if issued, will confirm that the United States has no valid interest...

  14. Cluster aspects of p-shell and sd-shell nuclei

    SciTech Connect

    Kanada-En'yo, Y.; Kobayashi, F.; Suhara, T.; Kimura, M.; Taniguchi, Y.

    2011-05-06

    We report some topics on cluster structures studied by using a theoretical method of antisymmetrized molecular dynamics(AMD). Cluster features of p-shell and sd-shell nuclei are discussed. In particular, three alpha cluster structures in the excited states of {sup 12}C and {sup 14}C are focused. Dineutron correlations in neutron-rich nuclei are also discussed.

  15. High Production of Squalene Using a Newly Isolated Yeast-like Strain Pseudozyma sp. SD301.

    PubMed

    Song, Xiaojin; Wang, Xiaolong; Tan, Yanzhen; Feng, Yingang; Li, Wenli; Cui, Qiu

    2015-09-30

    A yeast-like fungus, termed strain SD301, with the ability to produce a high concentration of squalene, was isolated from Shuidong Bay, China. The nucleotide sequence analysis of the internal transcribed spacer (ITS) region of SD301 indicated the strain belonged to Pseudozyma species. The highest biomass and squalene production of SD301 were obtained when glucose and yeast extracts were used as the carbon and nitrogen sources, respectively, with a C/N ratio of 3. The optimal pH and temperature were 6 and 25 °C, with 15 g L(-1) of supplemented sea salt. The maximum squalene productivity reached 0.039 g L(-1) h(-1) in batch fermentation, while the maximum squalene yield of 2.445 g L(-1) was obtained in fed-batch fermentation. According to our knowledge, this is the highest squalene yield produced thus far using fermentation technology, and the newly isolated strain Pseudozyma sp. SD301 is a promising candidate for commercial squalene production.

  16. AmeriFlux US-SdH Nebraska SandHills Dry Valley

    SciTech Connect

    Arkebauer, Tim J.; Billesbach, Dave

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site US-SdH Nebraska SandHills Dry Valley. Site Description - The Nebraska SandHills Dry Valley tower is located on public land owned by the University of Nebraska-Lincoln. The site is on a research cattle ranch where grazing primarily takes place.

  17. Linear in-wavenumber optical spectrum registration in SD-OCT

    NASA Astrophysics Data System (ADS)

    Gelikonov, Grigory V.; Gelikonov, Valentin M.; Shilyagin, Pavel A.

    2012-01-01

    An efficient technique of linear in-wavenumber optical spectrum registration in SD-OCT is proposed. Methods of partial phase correction of registered optical spectrum for in-wavenumber linearization are described and investigated. The decrease sensitivity decay with depth increasing degeneration is presented. The experimental results for sample media are presented.

  18. High Production of Squalene Using a Newly Isolated Yeast-like Strain Pseudozyma sp. SD301.

    PubMed

    Song, Xiaojin; Wang, Xiaolong; Tan, Yanzhen; Feng, Yingang; Li, Wenli; Cui, Qiu

    2015-09-30

    A yeast-like fungus, termed strain SD301, with the ability to produce a high concentration of squalene, was isolated from Shuidong Bay, China. The nucleotide sequence analysis of the internal transcribed spacer (ITS) region of SD301 indicated the strain belonged to Pseudozyma species. The highest biomass and squalene production of SD301 were obtained when glucose and yeast extracts were used as the carbon and nitrogen sources, respectively, with a C/N ratio of 3. The optimal pH and temperature were 6 and 25 °C, with 15 g L(-1) of supplemented sea salt. The maximum squalene productivity reached 0.039 g L(-1) h(-1) in batch fermentation, while the maximum squalene yield of 2.445 g L(-1) was obtained in fed-batch fermentation. According to our knowledge, this is the highest squalene yield produced thus far using fermentation technology, and the newly isolated strain Pseudozyma sp. SD301 is a promising candidate for commercial squalene production. PMID:26350291

  19. 76 FR 48120 - Black Hills National Forest, Custer, SD-Mountain Pine Beetle Response Project

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-08

    ... Forest Service Black Hills National Forest, Custer, SD--Mountain Pine Beetle Response Project AGENCY...: This project proposes to treat areas newly infested by mountain pine beetles on approximately 325,000...-rocky-mountain-black-hills@fs.fed.us , with ``MPB Response Project'' in the subject line....

  20. 78 FR 24228 - Lake Andes National Wildlife Refuge Complex, Lake Andes, SD; Final Comprehensive Conservation Plan

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-24

    ... review and comment following the announcement in the Federal Register on October 29, 2012 ] (77 FR 65574... Fish and Wildlife Service Lake Andes National Wildlife Refuge Complex, Lake Andes, SD; Final... Complex (Complex), which includes Lake Andes NWR, Karl E. Mundt NWR, and Lake Andes Wetland...

  1. 77 FR 65574 - Lake Andes National Wildlife Refuge Complex, Lake Andes, SD; Draft Comprehensive Conservation...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-29

    ... Complex. We started this process through a notice in the Federal Register (72 FR 27328; May, 15, 2007... Fish and Wildlife Service Lake Andes National Wildlife Refuge Complex, Lake Andes, SD; Draft... assessment (EA) for the Lake Andes National Wildlife Refuge Complex (Complex), which includes Lake Andes...

  2. Quasicontinuous spectrum of γ rays which feed and depopulate SD in ^194Pb.

    NASA Astrophysics Data System (ADS)

    McNabb, D. P.; Cizewski, J. A.; Ding, K.-Y.; Younes, W.; Khoo, T. L.; Lauritsen, T.; Archer, D. E.; Bauer, R. W.; Becker, J. A.; Bernstein, L. A.; Hauschild, K.; Clark, R. M.; Deleplanque, M. A.; Diamond, R. M.; Fallon, P.; Lee, I. Y.; Macchiavelli, A. O.; Stephens, F. S.; Kelly, W. H.

    1996-10-01

    The mechanism for decay from superdeformed (SD) to ``normal'' (ND) states in ^192Hg results in a large quasicontinuum component which can be fit by a statistical model.(R.G. Henry, et al., Phys. Rev. Lett. 73), 777 (1994). Recent experiments(M.J. Brinkman, et al., Phys. Rev. C53), R1461 (1996); T.L. Khoo, et al., Phys. Rev. Lett. 76, 1583 (1996). have also identified discrete one-step decays from SD to ND states in ^194Pb and ^194Hg which have allowed for the determination of excitation energy and spin of the second wells in these nuclei. We used the ^174Yb(^25Mg,5n) reaction at 130 MeV with a backed target and Gammasphere to study the total spectrum of γ rays in coincidence with the yrast SD band in ^194Pb. The response functions of the detectors were previously determined. The results of the preliminary analysis on the quasicontinuous γ rays which feed and depopulate the yrast SD band will be presented. This work was supported in part by the National Science Foundation and the U.S. Department of Energy.

  3. 78 FR 39310 - Niobrara Confluence and Ponca Bluffs Conservation Areas, NE and SD; Draft Environmental Impact...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-01

    ..., NE and SD; Draft Environmental Impact Statement and Land Protection Plan; Extension of the Public... Bluffs Conservation Areas Draft Environmental Impact Statement and Land Protection Plan until September... Ponca Bluff Conservation Areas. We are extending the public comment period until September 30, 2013....

  4. A wearable force plate system for the continuous measurement of triaxial ground reaction force in biomechanical applications

    NASA Astrophysics Data System (ADS)

    Liu, Tao; Inoue, Yoshio; Shibata, Kyoko

    2010-08-01

    The ambulatory measurement of ground reaction force (GRF) and human motion under free-living conditions is convenient, inexpensive and never restricted to gait analysis in a laboratory environment and is therefore much desired by researchers and clinical doctors in biomedical applications. A wearable force plate system was developed by integrating small triaxial force sensors and three-dimensional (3D) inertial sensors for estimating dynamic triaxial GRF in biomechanical applications. The system, in comparison to existent systems, is characterized by being lightweight, thin and easy-to-wear. A six-axial force sensor (Nitta Co., Japan) was used as a verification measurement device to validate the static accuracy of the developed force plate. To evaluate the precision during dynamic gait measurements, we compared the measurements of the triaxial GRF and the center of pressure (CoP) by using the developed system with the reference measurements made using a stationary force plate and an optical motion analysis system. The root mean square (RMS) differences of the two transverse components (x- and y-axes) and the vertical component (z-axis) of the GRF were 4.3 ± 0.9 N, 6.0 ± 1.3 N and 12.1 ± 1.1 N, respectively, corresponding to 5.1 ± 1.1% and 6.5 ± 1% of the maximum of each transverse component and 1.3 ± 0.2% of the maximum vertical component of GRF. The RMS distance between the two systems' CoP traces was 3.2 ± 0.8 mm, corresponding to 1.2 ± 0.3% of the length of the shoe. Moreover, based on the results of the assessment of the influence of the system on natural gait, we found that gait was almost never affected. Therefore, the wearable system as an alternative device can be a potential solution for measuring CoP and triaxial GRF in non-laboratory environments.

  5. New O(6) region near A = 130 and the interplay of triaxiality and gamma-softness in the IBA

    SciTech Connect

    Casten, R.F.

    1984-01-01

    A simple approach to the IBA is described, which exploits the consistent Q-formalism to describe both symmetries and transition regions with a minimum of parameters. Some results with this approach are discussed and compared with the data for deformed and transitional nuclei. Following this introduction, a new region of O(6) symmetry is presented and compared with the Pt region with which it is found to share many similarities. Discrepancies with the strict limiting symmetry are described in terms of symmetry breaking via a small triaxial potential. 28 refs., 15 figs.

  6. Location and stability of L1 for the elliptic restricted three-body problem with oblate and triaxial primaries

    NASA Astrophysics Data System (ADS)

    Masoud, Akram; Rahoma, Walid Ali; Abd El-Salam, Fawzy

    2016-07-01

    My subject of study is the point L1 with oblate and triaxial primaries in the elliptic restricted three-body problem (ERTBP). The study contains a mathematical determination of the location of this point in the form of a power series in the mass ratio and a discussion of its stability. The difference between the location of L1 in the perturbed ERTBP and in the classical circular restricted three-body problem (CRTBP) is graphically represented versus the mass ratio. To study the effect of a small displacement, a test particle is assumed to be subjected in the location of L1.

  7. Effects of radiation and triaxiality of primaries on triangular equilibrium points in elliptic restricted three body problem

    NASA Astrophysics Data System (ADS)

    Usha, T.; Narayan, A.; Ishwar, B.

    2014-01-01

    This paper studies the motion of an infinitesimal mass around triangular equilibrium points in the elliptic restricted three body problem assuming bigger primary as a source of radiation and the smaller one a triaxial rigid body. A practical application of this case could be the study of motion of a satellite under the effect of Sun and Earth. We have exploited the method of averaging used by Grebnikov (Nauka, Moscow, revised 1986) throughout the analysis of stability of the system. The critical mass ratio depends on the radiation pressure, oblateness, eccentricity and semi major axis of the elliptic orbits and the range of stability decreases as the radiation parameter increases.

  8. Poisson equations of rotational motion for a rigid triaxial body with application to a tumbling artificial satellite

    NASA Technical Reports Server (NTRS)

    Liu, J. J. F.; Fitzpatrick, P. M.

    1975-01-01

    A mathematical model is developed for studying the effects of gravity gradient torque on the attitude stability of a tumbling triaxial rigid satellite. Poisson equations are used to investigate the rotation of the satellite (which is in elliptical orbit about an attracting point mass) about its center of mass. An averaging method is employed to obtain an intermediate set of differential equations for the nonresonant, secular behavior of the osculating elements which describe the rotational motions of the satellite, and the averaged equations are then integrated to obtain long-term secular solutions for the osculating elements.

  9. Evolution from spherical single-particle structure to stable triaxiality at high spins in {sup 140}Nd

    SciTech Connect

    Petrache, C.M.; Fantuzi, M.; LoBianco, G.; Mengoni, D.; Neusser-Neffgen, A.; Huebel, H.; Al-Khatib, A.; Bringel, P.; Buerger, A.; Nenoff, N.; Schoenwasser, G.; Singh, A.K.; Ragnarsson, I.; Hagemann, G.B.; Herskind, B.; Jensen, D.R.; Sletten, G.; Fallon, P.; Goergen, A.; Bednarczyk, P.

    2005-12-15

    The level structure of {sub 60}{sup 140}Nd{sub 80} has been established up to spin 48 by in-beam {gamma}-ray spectroscopy by use of the {sup 96}Zr({sup 48}Ca, 4n) reaction. High-fold {gamma}-ray coincidences were measured with the EUROBALL spectrometer. Twelve new rotational bands have been discovered at high spins. They are interpreted as being formed in a deep triaxial minimum at {epsilon}{sub 2}{approx_equal}0.25 and {gamma}{approx_equal}35 deg. Possible configurations are assigned to the observed bands on the basis of configuration-dependent cranked Nilsson-Strutinsky calculations.

  10. The importance of triaxial shapes in spin aligned configurations in the A = 170-180 mass region

    SciTech Connect

    Bengtsson, R.

    1990-01-01

    Deformations determined from total routhian surfaces (TRS) for the yrast states of even-even isotopes of W, Os, and Pt are presented. The calculated deformations imply a number of specific features for the yrast line, resulting from deformation changes and the alignment of specific pairs of quasiparticles. The triaxial shapes predicted from the TRS are important for determining the character of the aligning particles as well as for making a correct interpretation of the strength of the interaction between crossing bands and the bandcrossing frequencies. 19 refs., 9 figs.

  11. Differential Susceptibility of SD and CD Rats to a Novel Rat Theilovirus

    PubMed Central

    Drake, Michael T; Riley, Lela K; Livingston, Robert S

    2008-01-01

    Antibodies to rat theilovirus (RTV) have been detected in rats for many years because of their serologic crossreactivity with strains of Theiler murine encephalomyelitis virus (TMEV) of mice. Little information exists regarding this pathogen, yet it is among the most common viruses detected in serologic surveys of rats used in research. In the study reported here, a novel isolate of RTV, designated RTV1, was cultured from the feces of infected rats. The RTV1 genome contained 8094 nucleotides and had approximately 95% identity with another rat theilovirus, NSG910, and 73% identity with TMEV strains. In addition, the genome size of RTV1 was similar to those of TMEV strains but larger than that reported for NSG910. Oral inoculation of Sprague–Dawley (SD) and CD male rats (n = 10 each group) with RTV1 revealed that SD rats were more susceptible than CD rats to RTV1 infection. At 14 d postinoculation, 100% of SD rats shed virus in the feces, and 70% were positive for RTV serum antibodies. By 56 d postinoculation 30% of SD rats continued to have detectable virus in the feces, and 90% had seroconverted. In contrast, in inoculated CD rats RTV was detected only in the feces at 14 d postinoculation, at which time 40% of CD rats were fecal positive. By 56 d postinoculation only 20% of CD rats had detectable RTV serum antibodies. Our data provide additional sequence information regarding a rat-specific Cardiovirus and indicate that SD rats are more susceptible than CD rats to RTV1 infection. PMID:19004372

  12. Strain Measurement of Geological Samples Subjected to Triaxial Stresses Experienced During Hydraulic Loading

    SciTech Connect

    An, Ke; Anovitz, Lawrence {Larry} M; Dessieux Jr, Luc Lucius

    2014-01-01

    locations, subjected to a triaxial stress state. The basis of the method and initial results for simple load conditions were reported at last year s Stanford Geothermal Workshop. This work will report results from recent neutron diffraction strain measurement experiments in which marble samples were subjected to load conditions more representative of hydraulic fracturing operations within a pressure cell specially designed for the reported strain measurement technique.

  13. Triaxiality, principal axis orientation and non-thermal pressure in Abell 383

    NASA Astrophysics Data System (ADS)

    Morandi, Andrea; Limousin, Marceau

    2012-04-01

    While clusters of galaxies are regarded as one of the most important cosmological probes, the conventional spherical modelling of the intracluster medium and the dark matter (DM), and the assumption of strict hydrostatic equilibrium (i.e. the equilibrium gas pressure is provided entirely by thermal pressure) are very approximate at best. Extending our previous works, we developed further a method to reconstruct for the first time the full 3D structure (triaxial shape and principal-axis orientation) of both DM and intracluster (IC) gas, and the level of non-thermal pressure of the IC gas. We outline an application of our method to the galaxy cluster Abell 383, taken as part of the Cluster Lensing and Supernova Survey with Hubble (CLASH) multicycle treasury programme, presenting results of a joint analysis of X-ray and strong lensing measurements. We find that the intermediate-major and minor-major axis ratios of the DM are 0.71 ± 0.10 and 0.55 ± 0.06, respectively, and the major axis of the DM halo is inclined with respect to the line of sight of 21?1 ± 10?1. The level of non-thermal pressure has been evaluated to be about 10 per cent of the total energy budget. We discuss the implications of our method for the viability of the cold dark matter (CDM) scenario, focusing on the concentration parameter C and the inner slope of the DM, γ, since the cuspiness of DM density profiles in the central regions is one of the critical tests of the CDM paradigm for structure formation: we measure γ= 1.02 ± 0.06 on scales down to 25 Kpc, and C= 4.76 ± 0.51, values which are close to the predictions of the standard model, and providing further evidences that support the CDM scenario. Our method allows us to recover the 3D physical properties of clusters in a bias-free way, overcoming the limitations of the standard spherical modelling and enhancing the use of clusters as more precise cosmological probes.

  14. Triaxial testing of Lopez Fault gouge at 150 MPa mean effective stress

    USGS Publications Warehouse

    Scott, D.R.; Lockner, D.A.; Byerlee, J.D.; Sammis, C.G.

    1994-01-01

    Triaxial compression experiments were performed on samples of natural granular fault gouge from the Lopez Fault in Southern California. This material consists primarily of quartz and has a self-similar grain size distribution thought to result from natural cataclasis. The experiments were performed at a constant mean effective stress of 150 MPa, to expose the volumetric strains associated with shear failure. The failure strength is parameterized by the coefficient of internal friction ??, based on the Mohr-Coulomb failure criterion. Samples of remoulded Lopez gouge have internal friction ??=0.6??0.02. In experiments where the ends of the sample are constrained to remain axially aligned, suppressing strain localisation, the sample compacts before failure and dilates persistently after failure. In experiments where one end of the sample is free to move laterally, the strain localises to a single oblique fault at around the point of failure; some dilation occurs but does not persist. A comparison of these experiments suggests that dilation is confined to the region of shear localisation in a sample. Overconsolidated samples have slightly larger failure strengths than normally consolidated samples, and smaller axial strains are required to cause failure. A large amount of dilation occurs after failure in heavily overconsolidated samples, suggesting that dilation is occurring throughout the sample. Undisturbed samples of Lopez gouge, cored from the outcrop, have internal friction in the range ??=0.4-0.6; the upper end of this range corresponds to the value established for remoulded Lopez gouge. Some kind of natural heterogeneity within the undisturbed samples is probably responsible for their low, variable strength. In samples of simulated gouge, with a more uniform grain size, active cataclasis during axial loading leads to large amounts of compaction. Larger axial strains are required to cause failure in simulated gouge, but the failure strength is similar to that of

  15. Understanding the mechanical and acoustical characteristics of sand aggregates compacting under triaxial conditions

    NASA Astrophysics Data System (ADS)

    Hangx, Suzanne; Brantut, Nicolas

    2016-04-01

    Mechanisms such as grain rearrangement, coupled with elastic deformation, grain breakage, grain rearrangement, grain rotation, and intergranular sliding, play a key role in determining porosity and permeability reduction during burial of clastic sediments. Similarly, in poorly consolidated, highly porous sands and sandstones, grain rotation, intergranular sliding, grain failure, and pore collapse often lead to significant reduction in porosity through the development of compaction bands, with the reduced porosity and permeability of such bands producing natural barriers to flow within reservoir rocks. Such time-independent compaction processes operating in highly porous water- and hydrocarbon-bearing clastic reservoirs can exert important controls on production-related reservoir deformation, subsidence, and induced seismicity. We performed triaxial compression experiments on sand aggregates consisting of well-rounded Ottawa sand (d = 300-400 μm; φ = 36.1-36.4%) at room temperature, to systematically investigate the effect of confining pressure (Pceff = 5-100 MPa), strain rate (10-6-10-4 s-1) and chemical environment (decane vs. water; Pf = 5 MPa) on compaction. For a limited number of experiments grain size distribution (d = 180-500 μm) and grain shape (subangular Beaujean sand; d = 180-300 μm) were varied to study their effect. Acoustic emission statistics and location, combined with microstructural and grain size analysis, were used to verify the operating microphysical compaction mechanisms. All tests showed significant pre-compaction during the initial hydrostatic (set-up) phase, with quasi-elastic loading behaviour accompanied by permanent deformation during the differential loading stage. This permanent volumetric strain involved elastic grain contact distortion, particle rearrangement, and grain failure. From the acoustic data and grain size analysis, it was evident that at low confining pressure grain rearrangement controlled compaction, with grain

  16. Modifications to the Paterson triaxial rock deformation apparatus to allow combined stress testing

    NASA Astrophysics Data System (ADS)

    May, S.; Mecklenburgh, J.; Xiao, W. F.; Covey-Crump, S. J.; Rutter, E. H.

    2010-12-01

    Almost all rock deformation experiments are performed in pure shear (axial compression or extension) or simple shear (torsion). However, in general, natural deformation can be expected to occur under some combination of these end member loading geometries. One of the most widely used apparatus for deforming geological samples at elevated temperatures and confining pressures is the Paterson triaxial rock deformation apparatus which is now installed in several experimental rock deformation facilities worldwide. In basic design this apparatus has the capacity for deforming samples under simultaneously applied axial loads and torques but modifications are required to the way in which axial load and torque are measured during such experiments if the mechanical data acquired are to be meaningful. Two design complications in particular arise. Firstly, at present axial load and torque are measured by a single slotted elastic element which undergoes measurable (and hence able to be calibrated) elastic distortions in response to applied axial loads and torques. The use of a single element presents no difficulties if either axial loads or torques are applied but when they are applied together the torque leads to an apparent but not real axial load and vice versa. Secondly, in a torsion test it is important to be able to detect the point during twisting at which all the slack within the rig - needed to allow test assembly - has been taken up and initial torque is applied to the sample. In a pure torsion test this is achieved by having a gap between the axial ram (containing the load cell) and the sample assembly but when there is a simultaneously applied axial load this gap is closed and the resulting friction at this surface means that torque is transferred to the load cell from the onset of twisting. In this contribution we show how a low-friction thrust bearing assembly located between the axial ram and sample assembly can be used to provide a relatively easy and

  17. Potential application of a triaxial three-dimensional fabric (3-DF) as an implant.

    PubMed

    Shikinami, Y; Kawarada, H

    1998-01-01

    Various three-dimensional fabrics (3-DFs) woven with a triaxial three-dimensional (3A-3D) structure in which the warps, wefts and vertical fibres are three-dimensionally orientated with orthogonal, off-angle, cylindrical or complex fibre alignments using a single long fibre, which may be one of several kinds of fibres, have been developed. The physical strengths and behaviour of these fabrics under different external forces were measured for such stress-strain relationships as compressive, tensile and cyclic bending, compressing torsional and compressive tensile systems to evaluate the effect of the continuous loading caused by living body movements over a long period of time. The 3-DFs led to downward convex 'J'-shaped curves in stress-strain profiles, because they were markedly flexible at low strain levels, but became rigid as strain increased. In this behaviour they reflected the behaviour of natural cartilage rather than that of conventional artificial biomaterials. There were also some 3-DFs that showed hysteresis loss curves with quite similar mechanical strengths and behaviour to natural intervertebral discs with regard to the compressive-tensile cyclic stress and showed little variation from the first 'J'-shaped hysteresis profile even after 100,000 deformation cycles. Accordingly, it has been shown that, without a doubt, 3-DFs can be effective implants possessing both design and mechanical biocompatibilities as well as the durability necessary for long-term implantation in the living body. The surface of bioinert linear low-density polyethylene coating on multifilaments of ultra-high molecular weight polyethylene, a constructional fibre of 3A-3D weaving, was modified by treatment with corona-discharge and spray-coating of unsintered hydroxyapatite powder to impart chemical (surface) compatibility and biological activity, respectively. Since the modified surface of the 3-DF was ascertained to have affinity and activity with simulated body fluid, an

  18. Energy Dissipation and Release During Coal Failure Under Conventional Triaxial Compression

    NASA Astrophysics Data System (ADS)

    Peng, Ruidong; Ju, Yang; Wang, J. G.; Xie, Heping; Gao, Feng; Mao, Lingtao

    2015-03-01

    Theoretical and experimental studies have revealed that energy dissipation and release play an important role in the deformation and failure of coal rocks. To determine the relationship between energy transformation and coal failure, the mechanical behaviors of coal specimens taken from a 600-m deep mine were investigated by conventional triaxial compression tests using five different confining pressures. Each coal specimen was scanned by microfocus computed tomography before and after testing to examine the crack patterns. Sieve analysis was used to measure the post-failure coal fragments, and a fractal model was developed for describing the size distribution of the fragments. Based on the test results, a damage evolution model of the rigidity degeneration of coal before the peak strength was also developed and used to determine the initial damage and critical damage variables. It was found that the peak strength increased with increasing confining pressure, but the critical damage variable was almost invariant. More new cracks were initiated in the coal specimens when there was no confining pressure or the pressure was too high. The parameters of failure energy ratio β and stress drop coefficient α are further proposed to describe the failure mode of coal under different confining pressures. The test results revealed that β was approximately linearly related to the fractal dimension of the coal fragments and that a higher failure energy ratio corresponded to a larger fractal dimension and more severe failure. The stress drop coefficient α decreased approximately exponentially with increasing confining pressure, and could be used to appropriately describe the evolution of the coal failure mode from brittle to ductile with increasing confining pressure. A large β and small α under a high confining pressure were noticed during the tests, which implied that the failure of the coal was a kind of pseudo-ductile failure. Brittle failure occurred when the confining

  19. Design and evaluation of a novel triaxial isometric trunk muscle strength measurement system.

    PubMed

    Azghani, M R; Farahmand, F; Meghdari, A; Vossoughi, G; Parnianpour, M

    2009-08-01

    Maximal strength measurements of the trunk have been used to evaluate the maximum functional capacity of muscles and the potential mechanical overload or overuse of the lumbar spine tissues in order to estimate the risk of developing musculoskeletal injuries. A new triaxial isometric trunk strength measurement system was designed and developed in the present study, and its reliability and performance was investigated. The system consisted of three main revolute joints, equipped with torque sensors, which intersect at L5-S1 and adjustment facilities to fit the body anthropometry and to accommodate both symmetric and asymmetric postures in both seated and standing positions. The dynamics of the system was formulated to resolve validly the moment generated by trunk muscles in the three anatomic planes. The optimal gain and offset of the system were obtained using deadweights based on the least-squares linear regression analysis. The R2 results of calibration for all loading courses of all joints were higher than 0.99, which indicated an excellent linear correlation. The results of the validation analysis of the regression model suggested that the mean absolute error and the r.m.s. error were less than 2 per cent of the applied load. The maximum value of the minimum detectable change was found to be 1.63 Nm for the sagittal plane torque measurement, 0.8 per cent of the full-scale load. The trial-to-trial variability analysis of the device using deadweights provided intra-class correlation coefficients of higher than 0.99, suggesting excellent reliability. The cross-talk analysis of the device indicated maximum cross-talks of 1.7 per cent and 3.4 per cent when the system was subjected to flexion-extension and lateral bending torques respectively. The trial-to-trial variability of the system during in-vivo strength measurement tests resulted in good to excellent reliability, with intra-class correlation coefficients ranging from 0.69 to 0.91. The results of the maximum

  20. Automated Segmentability Index for Layer Segmentation of Macular SD-OCT Images

    PubMed Central

    Lee, Kyungmoo; Buitendijk, Gabriëlle H.S.; Bogunovic, Hrvoje; Springelkamp, Henriët; Hofman, Albert; Wahle, Andreas; Sonka, Milan; Vingerling, Johannes R.; Klaver, Caroline C.W.; Abràmoff, Michael D.

    2016-01-01

    Purpose To automatically identify which spectral-domain optical coherence tomography (SD-OCT) scans will provide reliable automated layer segmentations for more accurate layer thickness analyses in population studies. Methods Six hundred ninety macular SD-OCT image volumes (6.0 × 6.0 × 2.3 mm3) were obtained from one eyes of 690 subjects (74.6 ± 9.7 [mean ± SD] years, 37.8% of males) randomly selected from the population-based Rotterdam Study. The dataset consisted of 420 OCT volumes with successful automated retinal nerve fiber layer (RNFL) segmentations obtained from our previously reported graph-based segmentation method and 270 volumes with failed segmentations. To evaluate the reliability of the layer segmentations, we have developed a new metric, segmentability index SI, which is obtained from a random forest regressor based on 12 features using OCT voxel intensities, edge-based costs, and on-surface costs. The SI was compared with well-known quality indices, quality index (QI), and maximum tissue contrast index (mTCI), using receiver operating characteristic (ROC) analysis. Results The 95% confidence interval (CI) and the area under the curve (AUC) for the QI are 0.621 to 0.805 with AUC 0.713, for the mTCI 0.673 to 0.838 with AUC 0.756, and for the SI 0.784 to 0.920 with AUC 0.852. The SI AUC is significantly larger than either the QI or mTCI AUC (P < 0.01). Conclusions The segmentability index SI is well suited to identify SD-OCT scans for which successful automated intraretinal layer segmentations can be expected. Translational Relevance Interpreting the quantification of SD-OCT images requires the underlying segmentation to be reliable, but standard SD-OCT quality metrics do not predict which segmentations are reliable and which are not. The segmentability index SI presented in this study does allow reliable segmentations to be identified, which is important for more accurate layer thickness analyses in research and population studies. PMID:27066311

  1. Permeability Changes of Coal Cores and Briquettes under Tri-Axial Stress Conditions

    NASA Astrophysics Data System (ADS)

    Wierzbicki, Mirosław; Konečný, Pavel; Kožušníková, Alena

    2014-12-01

    The paper is dealing with the permeability of coal in triaxial state of stress. The permeability of coal, besides coal's methane capacity, is the main parameter determining the quantity of methane inflow into underground excavations. The stress in a coal seam is one of the most important factors influencing coal permeability therefore the permeability measurements were performed in tri-axial state of stress. The hydrostatic three-axial state of stress was gradually increased from 5 MPa with steps of 5 MPa up to a maximum of 30 MPa. Nitrogen was applied as a gas medium in all experiments. The results of the permeability measurements of coal cores from the "Zofiówka" mine, Poland, and three mines from the Czech Republic are presented in this paper. As a "reference", permeability measurements were also taken for coal briquettes prepared from coal dust with defined porosity. It was confirmed that the decreasing porosity of coal briquettes affects the decreasing permeability. The advantage of experimentation on coal briquettes is its good repeatability. From the experimental results, an empirical relation between gas permeability and confining pressure has also been identified. The empirical relation for coal briquettes is in good correspondence with published results. However, for coal cores, the character of change differs. The influence of confining pressure has a different character and the decrease in permeability is stronger due to the increasing confining pressure Przepuszczalność węgla, oprócz pojemności sorpcyjnej względem metanu jest głównym parametrem określającym dopływ metanu do podziemnych wyrobiskach górniczych. W warunkach naturalnych wartość przepuszczalności jest ściśle związana ze stanem naprężenia w pokładzie węgla. W pracy przedstawiono wyniki pomiarów przepuszczalności wykonanych w trójosiowym stanie naprężenia. Hydrostatyczny trójosiowy stan naprężenia stopniowo zwiększano od 5 MPa do maksymalnie 30 MPa z krokiem

  2. Dynamic made-to-measure: A method of making dynamically self-consistent triaxial dark matter halos

    NASA Astrophysics Data System (ADS)

    Deg, Nathan James

    2010-11-01

    In this thesis we modify the Made-To-Measure (M2M) algorithm to be dynamically self-consistent and apply it to the problem of generating equilibrium collisionless systems with non-spherical halos. Our M2M algorithm systematically adjusts the masses of particles in a system slowly, keeping the system in equilibrium. The adjustments are performed according to some given constraints and proceed until pseudo-observations of the system match the constraints. We use this algorithm to generate isolated triaxial dark matter halos and disk-halo systems with prolate halos. The isolated triaxial dark-matter halo simulations provide a test for the algorithm. These tests show that our algorithm can generate equilibrium collisionless systems with non-spherical halos, but we also find that our algorithm requires a large amount of computational time to converge to the final target system. The disk-halo simulations show that prolate halos modify the morphology and velocity profile of dark matter dominated disks that cause errors in the measurement of the inclination and understanding the rotation curve. As a result of these errors, a mass estimate from the observed rotation curve of a disk in a prolate halo will depend on the observers position relative to the disk. The mass estimates from the same disk observed at different positions may vary by up to a factor of three.

  3. Some like it triaxial: the universality of dark matter halo shapes and their evolution along the cosmic time

    NASA Astrophysics Data System (ADS)

    Despali, Giulia; Giocoli, Carlo; Tormen, Giuseppe

    2014-10-01

    We present a detailed analysis of dark matter halo shapes, studying how the distributions of ellipticity, prolateness and axial ratios evolve as a function of time and mass. With this purpose in mind, we analysed the results of three cosmological simulations, running an ellipsoidal halo finder to measure triaxial halo shapes. The simulations have different scales, mass limits and cosmological parameters, which allows us to ensure a good resolution and statistics in a wide mass range, and to investigate the dependence of halo properties on the cosmological model. We confirm the tendency of haloes to be prolate at all times, even if they become more triaxial going to higher redshifts. Regarding the dependence on mass, more massive haloes are also less spherical at all redshifts, since they are the most recent forming systems and so still retain memory of their original shape at the moment of collapse. We then propose a rescaling of the shape-mass relations, using the variable ν = δc/σ to represent the mass, which absorbs the dependence on both cosmology and time, allowing us to find universal relations between halo masses and shape parameters (ellipticity, prolateness and the axial ratios) which hold at any redshift. This may be very useful to determine prior distributions of halo shapes for observational studies.

  4. Effect of open hole on tensile failure properties of 2D triaxial braided textile composites and tape equivalents

    NASA Technical Reports Server (NTRS)

    Norman, Timothy L.; Anglin, Colin; Gaskin, David; Patrick, Mike

    1995-01-01

    The unnotched and notched (open hole) tensile strength and failure mechanisms of two-dimensional (2D) triaxial braided composites were examined. The effect of notch size and notch position were investigated. Damage initiation and propagation in notched and unnotched coupons were also examined. Theory developed to predict the normal stress distribution near an open hole and failure for tape laminated composites was evaluated for its applicability to triaxial braided textile composite materials. Four fiber architectures were considered with different combinations of braid angle, longitudinal and braider yam size, and percentage of longitudinal yarns. Tape laminates equivalent to textile composites were also constructed for comparison. Unnotched tape equivalents were stronger than braided textiles but exhibited greater notch sensitivity. Notched textiles and tape equivalents have roughly the same strength at large notch sizes. Two common damage mechanisms were found: braider yams cracking and near notch longitudinal yarn splitting. Cracking was found to initiate in braider yarns in unnotched and notched coupons, and propagate in the direction of the braider yarns until failure. Longitudinal yarn splitting occurred in three of four architectures that were longitudinally fiber dominated. Damage initiation stress decreased with increasing braid angle. No significant differences in prediction of near notch stress between measured and predicted stress were weak for textiles with large braid angle. Notch strength could not be predicted using existing anisotropic theory for braided textiles due to their insensitivity to notch.

  5. Modification of a Macromechanical Finite-Element Based Model for Impact Analysis of Triaxially-Braided Composites

    NASA Technical Reports Server (NTRS)

    Goldberg, Robert K.; Blinzler, Brina J.; Binienda, Wieslaw K.

    2010-01-01

    A macro level finite element-based model has been developed to simulate the mechanical and impact response of triaxially-braided polymer matrix composites. In the analytical model, the triaxial braid architecture is simulated by using four parallel shell elements, each of which is modeled as a laminated composite. For the current analytical approach, each shell element is considered to be a smeared homogeneous material. The commercial transient dynamic finite element code LS-DYNA is used to conduct the simulations, and a continuum damage mechanics model internal to LS-DYNA is used as the material constitutive model. The constitutive model requires stiffness and strength properties of an equivalent unidirectional composite. Simplified micromechanics methods are used to determine the equivalent stiffness properties, and results from coupon level tests on the braided composite are utilized to back out the required strength properties. Simulations of quasi-static coupon tests of several representative braided composites are conducted to demonstrate the correlation of the model. Impact simulations of a represented braided composites are conducted to demonstrate the capability of the model to predict the penetration velocity and damage patterns obtained experimentally.

  6. Properties of triaxial, strongly deformed bands in {sup 167}Ta and {sup 167}Lu and the top-on-top model

    SciTech Connect

    Sugawara-Tanabe, Kazuko; Tanabe, Kosai

    2010-11-15

    Based on the particle-rotor model with one particle coupled to a triaxially deformed rotor, the experimental excitation energy relative to a reference E*-aI(I+1) and the ratio between interband and intraband electromagnetic transitions are well reproduced for {sup 167}Ta with {gamma}=19 deg. The same parameter set for the angular-momentum-dependent rigid-body moments of inertia attains good agreement with experimental data for the positive-parity triaxial, strongly deformed (TSD) band levels in {sup 167}Lu. An attempt is made to investigate the negative-parity TSD band in {sup 167}Lu.

  7. Quantification of soil/dust (SD) on the hands of children from Hubei Province, China using hand wipes.

    PubMed

    Wang, Siyu; Ma, Jin; Pan, Libo; Lin, Chunye; Wang, Beibei; Duan, Xiaoli

    2015-10-01

    A total of 120 children (58 males and 62 females) between the ages of 2 and 17 years were randomly selected from Wuhan City and Wufeng County in Hubei Province, China. We gathered hand SD samples from these children using hand wipes. We determined approximate amounts of hand SD and concentrations of three tracer soil elements (Ce, Y, V) in these samples. The approximate amounts of hand SD ranged from 6.35 to 85.42mg with a median value of 20.62mg. In addition, mean amounts of hand SD estimated using concentrations of Ce, Y, and V in samples were 1.07, 1.00, and 0.92mg, respectively. The amounts of hand SD varied greatly among age groups: primary school children had more hand SD than kindergarten and middle school children, males had more hand SD than females, and children from rural areas had more hand SD than those from urban areas. The rates of daily ingestion of hand SD for kindergarten, primary school, and middle school children were estimated as 1.79, 2.12, and 0.49mg/d, respectively.

  8. Fragmentation-aware service provisioning for advance reservation multicast in SD-EONs.

    PubMed

    Li, Shengru; Lu, Wei; Liu, Xiahe; Zhu, Zuqing

    2015-10-01

    In this paper, we study the service provisioning schemes for dynamic advance reservation (AR) multicast requests in elastic optical networks (EONs). We first propose several algorithms that can handle the service scheduling and routing and spectrum assignment (RSA) of AR multicast requests jointly, including an integrated two-dimensional fragmentation-aware RSA (2D-FMA) that can alleviate the 2D fragmentation caused by light-tree provisioning. Then, we leverage the idea of software-defined EONs (SD-EONs) that utilizes OpenFlow (OF) in the control plane to demonstrate and evaluate the proposed algorithms. Specifically, we build an SD-EON control plane testbed, implement the algorithms in it, and perform control plane experiments on dynamic AR multicast provisioning. The results indicate that 2D-FMA achieves the best blocking performance and provides the shortest average setup delay.

  9. Correlations of excited states for sd bosons in the presence of random interactions

    SciTech Connect

    Lei, Y.; Zhao, Y. M.; Yoshida, N.; Arima, A.

    2011-04-15

    In this work we study the yrast states of sd-boson systems in the presence of random interactions. It is found that the yrast states with spin-zero ground states among the random ensemble exhibit strong correlations, characterized by anharmonic vibration, s-boson or d-boson condensation, as well as vibrational and rotational motions. We study these correlations explicitly based on their wave functions and the features of two-body interactions in the random ensemble.

  10. FUV Spectroscopy of the sdOB Primary of the Eclipsing Binary System AA Dor

    NASA Astrophysics Data System (ADS)

    Fleig, J.; Rauch, T.; Werner, K.; Kruk, J. W.

    AADor is an eclipsing, close, post common-envelope binary (PCEB). We present a detailed spectral analysis of its sdOB primary based on observations obtained with the Far Ultraviolet Spectroscopic Explorer (FUSE). Due to a strong contamination by interstellar absorption, we had to model both, the stellar spectrum as well as the interstellar line absorption in order to reproduce the FUV observation well and to determine the photospheric parameters precisely.

  11. Inversion for Eigenvalues and Modes Using Sierra-SD and ROL.

    SciTech Connect

    Walsh, Timothy; Aquino, Wilkins; Ridzal, Denis; Kouri, Drew Philip

    2015-12-01

    In this report we formulate eigenvalue-based methods for model calibration using a PDE-constrained optimization framework. We derive the abstract optimization operators from first principles and implement these methods using Sierra-SD and the Rapid Optimization Library (ROL). To demon- strate this approach, we use experimental measurements and an inverse solution to compute the joint and elastic foam properties of a low-fidelity unit (LFU) model.

  12. The genome of Shigella dysenteriae strain Sd1617 comparison to representative strains in evaluating pathogenesis

    PubMed Central

    Vongsawan, Ajchara A.; Kapatral, Vinayak; Vaisvil, Benjamin; Burd, Henry; Serichantalergs, Oralak; Venkatesan, Malabi M.; Mason, Carl J.

    2015-01-01

    We sequenced and analyzed Shigella dysenteriae strain Sd1617 serotype 1 that is widely used as model strain for vaccine design, trials and research. A combination of next-generation sequencing platforms and assembly yielded two contigs representing a chromosome size of 4.34 Mb and the large virulence plasmid of 177 kb. This genome sequence is compared with other Shigella genomes in order to understand gene complexity and pathogenic factors. PMID:25743074

  13. Scientific Use of the Sampler, Drill and Distribution Subsystem (SD2)

    NASA Astrophysics Data System (ADS)

    Armellin, R.; Di Lizia, P.; Crepaldi, M.; Bernelli-Zazzera, F.; Ercoli Finzi, A.

    Rosetta is the third cornerstone mission of the European Space Agency scientific program "Horizon 2000". Rosetta will be the first spacecraft to orbit around a comet nucleus. It was launched in March 2004 and will reach the comet 67P/ChurymovGerasimenko in 2014. A lander (Philae) will be released and land on the comet surface for in-situ investigation. One of the key subsystems of the lander Philae is the Sampler, Drill and Distribution (SD2) subsystem. SD2 provides in-situ operations devoted to soil drilling, samples collection, and their distribution to two evolved gas analyzers (COSAC and PTOLEMY) and one imaging instrument (ÇIVA). Recent studies have proven the existence of a correlation between the drill behavior during perforation and the mechanical characteristics of the cometary soil. This outlines the possibility of using SD2 not only as a tool to support other instruments, but also as a scientific instrument itself. In this paper the possibility of using the drill as a quasi-static penetrator is presented. Within this approach, laboratory tests on glass-foam specimens of different porosity show that the drill behaviour during penetration can be exploited for cometary soil characterization.

  14. [Inactivation of HIV-1 in human femur heads using a heat disinfection system (Lobator SD-1)].

    PubMed

    von Garrel, T; Knaepler, H; Gürtler, L

    1997-05-01

    The use of allogenic bone transplants in surgery has been greatly diminished owing to the risk of transmitting infectious diseases. This risk can be reduced by the use of a thermal disinfection system (Lobator SD-1). This is achieved by increasing the temperature to 80 degrees C, inactivating a number of bacterial and viral agents. In this study the decay of HIV at high temperature in the Lobator SD-1 was researched. In the center of human femoral heads 100 microliters of a highly concentrated suspension of free and cell-bound HIV (10(10)) was exposed to the thermal process at intervals of 5, 10, 20, 30, 40, 50 and 62 min. For the recultivation HUT-78 cells were used through titration of the virus suspension in ten-fold dilutions over ten dilution steps and incubation up to a maximum of 21 days. Evidence of the virus was checked through observing giant cell formations and quantitative determination of p24 antigen using an Elisa test. Linear virus inactivation was found based upon the time the virus was exposed to heat. After a treatment of 40 min in the disinfection system, total virus inactivation was achieved. The normal disinfection process time using Lobator SD-1 is 92 min. A temperature of 80 degrees C is reached after approximately 45 min. The results prove that this system totally inactivates HIV in human femoral heads.

  15. Symmetry of Isoscalar Matrix Elements and Systematics in the sd and beginning of fp shells

    NASA Astrophysics Data System (ADS)

    Orce, J. N.; Petkov, P.; Velázquez, V.; McKay, C. J.; Lesher, S. R.; Choudry, S.; Mynk, M.; Linnemann, A.; Jolie, J.; von Brentano, P.; Werner, V.; Yates, S. W.; McEllistrem, M. T.

    2006-03-01

    A careful determination of the lifetime and measurement of the branching ratio for decay of the first 2T=1+ state in 42Sc has allowed an accurate experimental test of charge independence in the A = 42 isobaric triplet. A lifetime of 69(17) fs was measured at the University of Kentucky, while relative intensities for the 975 keV and 1586 keV transitions depopulating the first 2T=1+ state have been determined at the University of Cologne as 100(1) and 8(1), respectively. Both measurements give an isoscalar matrix element, M0, of 6.4(9) (W.u.)1/2. This result confirms charge independence for the A=42 isobaric triplet. Shell model calculations have been carried out for understanding the global trend of M0 values for A = 4n + 2 isobaric triplets ranging from A = 18 to A = 42. The 21 (T=1)+ → 01 (T=1)+ transition energies, reduced transition probabilities and M0 values are reproduced to a high degree of accuracy. The trend of M0 strength along the sd shell is interpreted in terms of the shell structure. Certain discrepancies arise at the extremes of the sd shell, for the A = 18 and A = 38 isobaric triplets, which might be explained in terms of the low valence space at the extremes of the sd shell.

  16. Metabolomics approach to serum biomarker for loperamide-induced constipation in SD rats.

    PubMed

    Kim, Ji-Eun; Lee, Young-Ju; Kwak, Moon-Hwa; Jun, Go; Koh, Eun-Kyoung; Song, Sung-Hwa; Seong, Ji-Eun; Kim, Ji Won; Kim, Kyu-Bong; Kim, Suhkmann; Hwang, Dae-Youn

    2014-03-01

    Loperamide has long been known as an opioid-receptor agonist useful as a drug for treatment of diarrhea resulting from gastroenteritis or inflammatory bowel disease as well as to induce constipation. To determine and characterize putative biomarkers that can predict constipation induced by loperamide treatment, alteration of endogenous metabolites was measured in the serum of Sprague Dawley (SD) rats treated with loperamide for 3 days using (1)H nuclear magnetic resonance ((1)H NMR) spectral data. The amounts and weights of stool and urine excretion were significantly lower in the loperamide-treated group than the No-treated group, while the thickness of the villus, crypt layer, and muscle layer was decreased in the transverse colon of the same group. The concentrations of aspartate aminotransferase (AST), lactate dehydrogenase (LDH) and creatinine (Cr) were also slightly changed in the loperamide-treated group, although most of the serum components were maintained at a constant level. Furthermore, pattern recognition of endogenous metabolites showed completely separate clustering of the serum analysis parameters between the No-treated group and loperamide-treated group. Among 35 endogenous metabolites, four amino acids (alanine, glutamate, glutamine and glycine) and six endogenous metabolites (acetate, glucose, glycerol, lactate, succinate and taurine) were dramatically decreased in loperamide-treated SD rats. These results provide the first data pertaining to metabolic changes in SD rats with loperamide-induced constipation. Additionally, these findings correlate the changes in 10 metabolites with constipation. PMID:24707303

  17. Metabolomics approach to serum biomarker for loperamide-induced constipation in SD rats

    PubMed Central

    Kim, Ji-Eun; Lee, Young-Ju; Kwak, Moon-Hwa; Jun, Go; Koh, Eun-Kyoung; Song, Sung-Hwa; Seong, Ji-Eun; Kim, Ji Won; Kim, Kyu-Bong; Kim, Suhkmann

    2014-01-01

    Loperamide has long been known as an opioid-receptor agonist useful as a drug for treatment of diarrhea resulting from gastroenteritis or inflammatory bowel disease as well as to induce constipation. To determine and characterize putative biomarkers that can predict constipation induced by loperamide treatment, alteration of endogenous metabolites was measured in the serum of Sprague Dawley (SD) rats treated with loperamide for 3 days using 1H nuclear magnetic resonance (1H NMR) spectral data. The amounts and weights of stool and urine excretion were significantly lower in the loperamide-treated group than the No-treated group, while the thickness of the villus, crypt layer, and muscle layer was decreased in the transverse colon of the same group. The concentrations of aspartate aminotransferase (AST), lactate dehydrogenase (LDH) and creatinine (Cr) were also slightly changed in the loperamide-treated group, although most of the serum components were maintained at a constant level. Furthermore, pattern recognition of endogenous metabolites showed completely separate clustering of the serum analysis parameters between the No-treated group and loperamide-treated group. Among 35 endogenous metabolites, four amino acids (alanine, glutamate, glutamine and glycine) and six endogenous metabolites (acetate, glucose, glycerol, lactate, succinate and taurine) were dramatically decreased in loperamide-treated SD rats. These results provide the first data pertaining to metabolic changes in SD rats with loperamide-induced constipation. Additionally, these findings correlate the changes in 10 metabolites with constipation. PMID:24707303

  18. Multimodal segmentation of optic disc and cup from stereo fundus and SD-OCT images

    NASA Astrophysics Data System (ADS)

    Miri, Mohammad Saleh; Lee, Kyungmoo; Niemeijer, Meindert; Abràmoff, Michael D.; Kwon, Young H.; Garvin, Mona K.

    2013-03-01

    Glaucoma is one of the major causes of blindness worldwide. One important structural parameter for the diagnosis and management of glaucoma is the cup-to-disc ratio (CDR), which tends to become larger as glaucoma progresses. While approaches exist for segmenting the optic disc and cup within fundus photographs, and more recently, within spectral-domain optical coherence tomography (SD-OCT) volumes, no approaches have been reported for the simultaneous segmentation of these structures within both modalities combined. In this work, a multimodal pixel-classification approach for the segmentation of the optic disc and cup within fundus photographs and SD-OCT volumes is presented. In particular, after segmentation of other important structures (such as the retinal layers and retinal blood vessels) and fundus-to-SD-OCT image registration, features are extracted from both modalities and a k-nearest-neighbor classification approach is used to classify each pixel as cup, rim, or background. The approach is evaluated on 70 multimodal image pairs from 35 subjects in a leave-10%-out fashion (by subject). A significant improvement in classification accuracy is obtained using the multimodal approach over that obtained from the corresponding unimodal approach (97.8% versus 95.2%; p < 0:05; paired t-test).

  19. Geology of the USW SD-12 drill hole Yucca Mountain, Nevada

    SciTech Connect

    Rautman, C.A.; Engstrom, D.A.

    1996-11-01

    Drill hole USW SD-12 is one of several holes drilled under Site Characterization Plan Study 8.3.1.4.3.1, also known as the {open_quotes}Systematic Drilling Program,{close_quotes} as part of the U.S. Department of Energy characterization program at Yucca Mountain, Nevada, which has been proposed as the potential location of a repository for high-level nuclear waste. The SD-12 drill hole is located in the central part of the potential repository area, immediately to the west of the Main Test Level drift of the Exploratory Studies Facility and slightly south of midway between the North Ramp and planned South Ramp declines. Drill hole USW SD-12 is 2166.3 ft (660.26 m) deep, and the core recovered essentially complete sections of ash-flow tuffs belonging to the lower half of the Tiva Canyon Tuff, the Pah Canyon Tuff, and the Topopah Spring Tuff, all of which are part of the Miocene Paintbrush Group. A virtually complete section of the Calico Hills Formation was also recovered, as was core from the entire Prow Pass Tuff formation of the Crater Flat Group.

  20. Uncertainty resulting from multiple data usage in statistical downscaling

    NASA Astrophysics Data System (ADS)

    Kannan, S.; Ghosh, Subimal; Mishra, Vimal; Salvi, Kaustubh

    2014-06-01

    Statistical downscaling (SD), used for regional climate projections with coarse resolution general circulation model (GCM) outputs, is characterized by uncertainties resulting from multiple models. Here we observe another source of uncertainty resulting from the use of multiple observed and reanalysis data products in model calibration. In the training of SD, for Indian Summer Monsoon Rainfall (ISMR), we use two reanalysis data as predictors and three gridded data products for ISMR from different sources. We observe that the uncertainty resulting from six possible training options is comparable to that resulting from multiple GCMs. Though the original GCM simulations project spatially uniform increasing change of ISMR, at the end of 21st century, the same is not obtained with SD, which projects spatially heterogeneous and mixed changes of ISMR. This is due to the differences in statistical relationship between rainfall and predictors in GCM simulations and observed/reanalysis data, and SD considers the latter.

  1. Using Tri-Axial Accelerometers to Assess the Dynamic Control of Head Posture During Gait

    NASA Technical Reports Server (NTRS)

    Lawrence, John H., III

    2003-01-01

    Long duration spaceflight is known to cause a variety of biomedical stressors to the astronaut. One of the more functionally destabilizing effects of spaceflight involves microgravity-induced changes in vestibular or balance control. Balance control requires the integration of the vestibular, visual, and proprioceptive systems. In the microgravity environment, the normal gravity vector present on Earth no longer serves as a reference for the balance control system. Therefore, adaptive changes occur to the vestibular system to affect control of body orientation with altered, or non-present, gravity and/or proprioceptive inputs. Upon return to a gravity environment, the vestibular system must re-incorporate the gravity vector and gravity-induced proprioceptive inputs into the balance control regime. The result is often a period of postural instability, which may also be associated with space motion sickness (oscillopsia, nausea, and vertigo). Previous studies by the JSC Neuroscience group have found that returning astronauts often employ alterations in gait mechanics to maintain postural control during gait. It is believed that these gait alterations are meant to decrease the transfer of heel strike shock energy to the head, thus limiting the contradictory head and eye movements that lead to gait instability and motion sickness symptoms. We analyzed pre- and post-spaceflight tri-axial accelerometer data from the NASA/MIR long duration spaceflight missions to assess the heel to head transfer of heel strike shock energy during locomotion. Up to seven gait sessions (three preflight, four postflight) of head and shank (lower leg) accelerometer data was previously collected from six astronauts who engaged in space flights of four to six months duration. In our analysis, the heel to head transmission of shock energy was compared using peak vertical acceleration (a), peak jerk (j) ratio, and relative kinetic energy (a). A host of generalized movement variables was produced

  2. Geology of the USW SD-7 drill hole Yucca Mountain, Nevada

    SciTech Connect

    Rautman, C.A.; Engstrom, D.A.

    1996-09-01

    The USW SD-7 drill hole is one of several holes drilled under Site Characterization Plan Study 8.3.1.4.3.1, also known as the Systematic Drilling Program, as part of the U.S. Department of Energy characterization program at Yucca Mountain, Nevada. The Yucca Mountain site has been proposed as the potential location of a repository for high-level nuclear waste. The SD-7 drill hole is located near the southern end of the potential repository area and immediately to the west of the Main Test Level drift of the Exploratory Studies Facility. The hole is not far from the junction of the Main Test Level drift and the proposed South Ramp decline. Drill hole USW SD-7 is 2675.1 ft (815.3 m) deep, and the core recovered nearly complete sections of ash-flow tuffs belonging to the lower half of the Tiva Canyon Tuff, the Pah Canyon Tuff, and the Topopah Spring Tuff, all of which are part of the Miocene Paintbrush Group. Core was recovered from much of the underlying Calico Hills Formation, and core was virtually continuous in the Prow Pass Tuff and the Bullfrog Tuff. The SD-7 drill hole penetrated the top several tens of feet into the Tram Tuff, which underlies the Prow Pass and Bullfrog Tuffs. These latter three units are all formations of the Crater Flat Group, The drill hole was collared in welded materials assigned to the crystal-poor middle nonlithophysal zone of the Tiva Canyon Tuff; approximately 280 ft (85 m) of this ash-flow sheet was penetrated by the hole. The Yucca Mountain Tuff appears to be missing from the section at the USW SD-7 location, and the Pah Canyon Tuff is only 14.5 ft thick. The Pah Canyon Tuff was not recovered in core because of drilling difficulties, suggesting that the unit is entirely nonwelded. The presence of this unit is inferred through interpretation of down-hole geophysical logs.

  3. Creation of short microwave ablation zones: In Vivo Characterization of single and paired Modified Triaxial Antennas Laboratory Investigation

    PubMed Central

    Lubner, Meghan G.; Ziemlewicz, Tim J; Hinshaw, J. Louis; Lee, Fred T.; Sampson, Lisa J.; Brace, Chris L.

    2014-01-01

    Purpose To characterize modified triaxial microwave antennas configured to produce short ablation zones. Materials and Methods 50 single- and 27 paired-antenna hepatic ablations were performed in domestic swine (n=11) with 17-gauge, gas-cooled modified triaxial antennas powered at 65W from a 2.45 GHz generator. Single-antenna ablations were performed at 2 (n=16), 5 (n=21), and 10 (n=13) minutes. Paired-antenna ablations were performed at 1-cm and 2-cm spacing for 5 (n=7, n=8) and 10 minutes (n=7, n=5). Mean transverse width, length and aspect ratio of sectioned ablation zones were measured and compared. Results For single antennas, mean ablation zone length was 2.9±0.45, 3.5±0.55 and 4.2±0.40 cm at 2, 5, and 10 minutes respectively. Mean width was 1.8±0.3, 2.0±0.32, 2.5±0.25 cm at 2, 5, and 10 minutes. For paired antennas, mean length at 5 min 1 and 2 cm and 10 min 1 and 2 cm spacing was 4.2±0.9, 4.4±0.9, 4.8±0.5 and 4.3±0.9 cm respectively. Mean width was 3.1±1.0, 4.0±0.8 and 3.8±0.4, 4.2±0.6 cm respectively. Paired-antenna ablations were more spherical (aspect ratios 0.72-0.79 for 5-10 min) than single-antenna ablations (0.57-0.59). For paired-antenna ablations, 1 cm spacing appeared optimal, with improved circularity and decreased clefting compared to 2 cm spacing (circ 1 cm 0.85, 2 cm 0.78). Conclusion Modified triaxial antennas can generate relatively short, spherical ablation zones. Paired-antenna ablations were rounder and larger in transverse dimension compared to single antenna ablations, with 1 cm spacing optimal for confluence of the ablation zone. PMID:25156644

  4. Complete Genome Sequence of Geobacter anodireducens SD-1T, a Salt-Tolerant Exoelectrogenic Microbe in Bioelectrochemical Systems.

    PubMed

    Sun, Dan; Cheng, Shaoan; Wang, Aijie; Huang, Fangliang; Liu, Wenzong; Xia, Xue

    2016-01-01

    Strain SD-1 is the type strain of the species Geobacter anodireducens, which was originally isolated from a microbial fuel cell reactor in the United States. The characteristic of this bacterium is its high electrochemical activity. Here, we report the fully assembled genome and plasmid sequence of G. anodireducens SD-1(T). PMID:27257213

  5. Complete Genome Sequence of Geobacter anodireducens SD-1T, a Salt-Tolerant Exoelectrogenic Microbe in Bioelectrochemical Systems

    PubMed Central

    Wang, Aijie; Huang, Fangliang; Liu, Wenzong; Xia, Xue

    2016-01-01

    Strain SD-1 is the type strain of the species Geobacter anodireducens, which was originally isolated from a microbial fuel cell reactor in the United States. The characteristic of this bacterium is its high electrochemical activity. Here, we report the fully assembled genome and plasmid sequence of G. anodireducens SD-1T. PMID:27257213

  6. Tri-axial magnetic anisotropies in RE{sub 2}Ba{sub 4}Cu{sub 7}O{sub 15−y} superconductors

    SciTech Connect

    Horii, Shigeru Doi, Toshiya; Okuhira, Shota; Yamaki, Momoko; Kishio, Kohji; Shimoyama, Jun-ichi

    2014-03-21

    We report a novel quantification method of tri-axial magnetic anisotropy in orthorhombic substances containing rare earth (RE) ions using tri-axial magnetic alignment and tri-axial magnetic anisotropies depending on the type of RE in RE-based cuprate superconductors. From the changes in the axes for magnetization in magnetically aligned powders of (RE′{sub 1−x}RE″{sub x}){sub 2}Ba{sub 4}Cu{sub 7}O{sub y} [(RE′,RE″)247] containing RE ions with different single-ion magnetic anisotropies, the ratios of three-dimensional magnetic anisotropies between RE′247 and RE″247 could be determined. The results in (Y,Er)247, (Dy,Er)247, (Ho,Er)247, and (Y,Eu)247 systems suggest that magnetic anisotropies largely depended on the type of RE′ (or RE″), even in the heavy RE ions with higher magnetic anisotropies. An appropriate choice of RE ions in RE-based cuprate superconductors enables the reduction of the required magnetic field for the production of their bulks and thick films based on the tri-axial magnetic alignment technique using modulated rotation magnetic fields.

  7. Self-cementing properties of crushed demolished concrete in unbound layers: results from triaxial tests and field tests.

    PubMed

    Arm, M

    2001-01-01

    A 2-year study is underway to evaluate the expected growth in stiffness in layers of crushed concrete from demolished structures. This growth is said to be a result of self-cementing properties. The study consists of repeated load triaxial tests on manufactured specimens after different storing time together with falling weight deflectometer, FWD, measurements on test sections. Results so far show a clear increase with time in resilient modulus and in back-calculated layer modulus for all concrete materials. The increase is the largest in the first months and then diminishes. The field measurements show a more considerable growth in stiffness than the laboratory tests, with a doubled value two years after construction. Comparative investigations on natural aggregates, mostly crushed granite do not show any growth in stiffness, neither in the laboratory nor in the field. Consequences for the choice of design modulus are discussed.

  8. Child activity recognition based on cooperative fusion model of a triaxial accelerometer and a barometric pressure sensor.

    PubMed

    Nam, Yunyoung; Park, Jung Wook

    2013-03-01

    This paper presents a child activity recognition approach using a single 3-axis accelerometer and a barometric pressure sensor worn on a waist of the body to prevent child accidents such as unintentional injuries at home. Labeled accelerometer data are collected from children of both sexes up to the age of 16 to 29 months. To recognize daily activities, mean, standard deviation, and slope of time-domain features are calculated over sliding windows. In addition, the FFT analysis is adopted to extract frequency-domain features of the aggregated data, and then energy and correlation of acceleration data are calculated. Child activities are classified into 11 daily activities which are wiggling, rolling, standing still, standing up, sitting down, walking, toddling, crawling, climbing up, climbing down, and stopping. The overall accuracy of activity recognition was 98.43% using only a single- wearable triaxial accelerometer sensor and a barometric pressure sensor with a support vector machine.

  9. Critical study of the method of calculating virgin rock stresses from measurement results of the CSIR triaxial strain cell

    NASA Astrophysics Data System (ADS)

    Vreede, F. A.

    1981-05-01

    The manual of instructions for the user of the CSIR triaxial rock stress measuring equipment is critically examined. It is shown that the values of the rock stresses can be obtained from the strain gauge records by means of explicit formulae, which makes the manual's computer program obsolete. Furthermore statistical methods are proposed to check for faulty data and inhomogeneity in rock properties and virgin stress. The possibility of non-elastic behavior of the rock during the test is also checked. A new computer program based on the explicit functions and including the check calculations is presented. It is much more efficient than the one in the manual since it does not require computer sub-routines, allowing it to be used directly on any modern computer. The output of the new program is in a format suitable for direct inclusion in the report of an investigation using strain cell results.

  10. Triaxial tunable mechanical monolithic sensors for large band low frequency monitoring and characterization of sites and structures

    NASA Astrophysics Data System (ADS)

    Barone, F.; Giordano, G.; Acernese, F.; Romano, R.

    2016-04-01

    This paper describes the application of the monolithic UNISA Folded Pendulum, optimized as inertial sensor (seismometer) for low frequency applications for characterization of sites (including underground sites) and structures (e.g. buildings, bridges, historical monuments), but, in general, for applications requiring large band low-frequency performances coupled with high sensitivities. The main characteristics of this class of sensors are high sensitivity, large measurement band, compactness, lightness, scalability, tunability of the resonance frequency, low thermal noise and very good immunity to environmental noises. The horizontal and vertical versions of folded pendulum allow an effective state-of-the-art mechanical implementation of triaxial sensors, configurable both as seismometer and/or as accelerometer.

  11. The Mysterious sdO X-ray Binary BD+37°442

    NASA Astrophysics Data System (ADS)

    Heber, U.; Geier, S.; Irrgang, A.; Schneider, D.; Barbu-Barna, I.; Mereghetti, S.; La Palombara, N.

    2014-04-01

    Pulsed X-ray emission in the luminous, helium-rich sdO BD +37°442 has recently been discovered (La Palombara et al. 2012). It was suggested that the sdO star has a neutron star or white dwarf companion with a spin period of 19.2 s. After HD 49798, which has a massive white dwarf companion spinning at 13.2 s in an 1.55 day orbit, this is only the second O-type subdwarf from which X-ray emission has been detected. We report preliminary results of our ongoing campaign to obtain time-resolved high-resolution spectroscopy using the CAFE instrument at Calar Alto observatory and SARG at the Telescopio Nationale Galileo. Atmospheric parameters were derived via a quantitative NLTE spectral analysis. The line fits hint at an unusually large projected rotation velocity. Therefore it seemed likely that BD +37°442 is a binary similar to HD 49798 and that the orbital period is also similar. The level of X-ray emission from BD +37°442 could be explained by accretion from the sdO wind by a neutron star orbiting at a period of less than ten days. Hence, we embarked on radial velocity monitoring in order to derive the binary parameters of the BD+37°442 system and obtained 41 spectra spread out over several month in 2012. Unlike for HD 49798, no radial velocity variations were found and, hence, there is no dynamical evidence for the existence of a compact companion yet. The origin of the pulsed X-ray emission remains as a mystery.

  12. Correlation between SD-OCT, immunocytochemistry and functional findings in an animal model of retinal degeneration

    PubMed Central

    Cuenca, Nicolás; Fernández-Sánchez, Laura; Sauvé, Yves; Segura, Francisco J.; Martínez-Navarrete, Gema; Tamarit, José Manuel; Fuentes-Broto, Lorena; Sanchez-Cano, Ana; Pinilla, Isabel

    2014-01-01

    Purpose: The P23H rhodopsin mutation is an autosomal dominant cause of retinitis pigmentosa (RP). The degeneration can be tracked using different anatomical and functional methods. In our case, we evaluated the anatomical changes using Spectral-Domain Optical Coherence Tomography (SD-OCT) and correlated the findings with retinal thickness values determined by immunocytochemistry.Methods: Pigmented rats heterozygous for the P23H mutation, with ages between P18 and P180 were studied. Function was assessed by means of optomotor testing and ERGs. Retinal thicknesses measurements, autofluorescence and fluorescein angiography were performed using Spectralis OCT. Retinas were studied by means of immunohistochemistry. Results: Between P30 and P180, visual acuity decreased from 0.500 to 0.182 cycles per degree (cyc/deg) and contrast sensitivity decreased from 54.56 to 2.98 for a spatial frequency of 0.089 cyc/deg. Only cone-driven b-wave responses reached developmental maturity. Flicker fusions were also comparable at P29 (42 Hz). Double flash-isolated rod-driven responses were already affected at P29. Photopic responses revealed deterioration after P29.A reduction in retinal thicknesses and morphological modifications were seen in OCT sections. Statistically significant differences were found in all evaluated thicknesses. Autofluorescence was seen in P23H rats as sparse dots. Immunocytochemistry showed a progressive decrease in the outer nuclear layer (ONL), and morphological changes. Although anatomical thickness measures were significantly lower than OCT values, there was a very strong correlation between the values measured by both techniques.Conclusions: In pigmented P23H rats, a progressive deterioration occurs in both retinal function and anatomy. Anatomical changes can be effectively evaluated using SD-OCT and immunocytochemistry, with a good correlation between their values, thus making SD-OCT an important tool for research in retinal degeneration. PMID:25565976

  13. A complex noise reduction method for improving visualization of SD-OCT skin biomedical images

    NASA Astrophysics Data System (ADS)

    Myakinin, Oleg O.; Zakharov, Valery P.; Bratchenko, Ivan A.; Kornilin, Dmitry V.; Khramov, Alexander G.

    2014-05-01

    In this paper we consider the original method of solving noise reduction problem for visualization's quality improvement of SD-OCT skin and tumors biomedical images. The principal advantages of OCT are high resolution and possibility of in vivo analysis. We propose a two-stage algorithm: 1) process of raw one-dimensional A-scans of SD-OCT and 2) remove a noise from the resulting B(C)-scans. The general mathematical methods of SD-OCT are unstable: if the noise of the CCD is 1.6% of the dynamic range then result distortions are already 25-40% of the dynamic range. We use at the first stage a resampling of A-scans and simple linear filters to reduce the amount of data and remove the noise of the CCD camera. The efficiency, improving productivity and conservation of the axial resolution when using this approach are showed. At the second stage we use an effective algorithms based on Hilbert-Huang Transform for more accurately noise peaks removal. The effectiveness of the proposed approach for visualization of malignant and benign skin tumors (melanoma, BCC etc.) and a significant improvement of SNR level for different methods of noise reduction are showed. Also in this study we consider a modification of this method depending of a specific hardware and software features of used OCT setup. The basic version does not require any hardware modifications of existing equipment. The effectiveness of proposed method for 3D visualization of tissues can simplify medical diagnosis in oncology.

  14. Sex differences in the behavioral response to methylphenidate in three adolescent rat strains (WKY, SHR, SD).

    PubMed

    Chelaru, Mircea I; Yang, Pamela B; Dafny, Nachum

    2012-01-01

    Methylphenidate (MPD) is the most widely used drug in the treatment of attention-deficit hyperactivity disorder (ADHD). ADHD has a high incidence in children and can persist in adolescence and adulthood. The relation between sex and the effects of acute and chronic MPD treatment was examined using adolescent male and female rats from three genetically different strains: spontaneously hyperactive rat (SHR), Wistar-Kyoto (WKY) and Sprague-Dawley (SD). Rats from each strain and sex were randomly divided into a control group that received saline injections and three MPD groups that received either 0.6 or 2.5 or 10mg/kg MPD injections. All rats received saline on experimental day 1 (ED1). On ED2 to ED7 and ED11, the rats were injected either with saline or MPD and received no treatment on ED8-ED10. The open field assay was used to assess the dose-response of acute and chronic MPD administration. Significant sex differences were found. Female SHR and SD rats were significantly more active after MPD injections than their male counterparts, while the female WKY rats were less active than the male WKY rats. Dose dependent behavioral sensitization or tolerance to MPD treatment was not observed for SHR or SD rats, but tolerance to MPD was found in WKY rats for the 10mg/kg MPD dose. The use of dose-response protocol and evaluating different locomotor indices provides the means to identify differences between the sexes and the genetic strain in adolescent rats. In addition these differences suggest that the differences to MPD treatment between the sexes are not due to the reproductive hormones.

  15. EXOTIME: Searching for planets and measuring \\dot{P} in sdB pulsators

    NASA Astrophysics Data System (ADS)

    Lutz, R.; Schuh, S.; Silvotti, R.

    2012-12-01

    We review the status of the EXOTIME project (EXOplanet search with the TIming MEthod). The two main goals of EXOTIME are to search for sub-stellar companions to sdB stars in wide orbits, and to measure the secular variation of the pulsation periods, which are related to the evolutionary change of the stellar structure. Now, after four years of dense monitoring, we start to see some results and present the brown dwarf and exoplanet candidates V1636 Ori b and DW Lyn b.

  16. The Evolution of the Globular Cluster System in a Triaxial Galaxy: Can a Galactic Nucleus Form by Globular Cluster Capture?

    NASA Astrophysics Data System (ADS)

    Capuzzo-Dolcetta, Roberto

    1993-10-01

    Among the possible phenomena inducing evolution of the globular cluster system in an elliptical galaxy, dynamical friction due to field stars and tidal disruption caused by a central nucleus is of crucial importance. The aim of this paper is the study of the evolution of the globular cluster system in a triaxial galaxy in the presence of these phenomena. In particular, the possibility is examined that some galactic nuclei have been formed by frictionally decayed globular clusters moving in a triaxial potential. We find that the initial rapid growth of the nucleus, due mainly to massive clusters on box orbits falling in a short time scale into the galactic center, is later slowed by tidal disruption induced by the nucleus itself on less massive clusters in the way described by Ostriker, Binney, and Saha. The efficiency of dynamical friction is such to carry to the center of the galaxy enough globular cluster mass available to form a compact nucleus, but the actual modes and results of cluster-cluster encounters in the central potential well are complicated phenomena which remains to be investigated. The mass of the resulting nucleus is determined by the mutual feedback of the described processes, together with the initial spatial, velocity, and mass distributions of the globular cluster family. The effect on the system mass function is studied, showing the development of a low- and high-mass turnover even with an initially flat mass function. Moreover, in this paper is discussed the possibility that the globular cluster fall to the galactic center has been a cause of primordial violent galactic activity. An application of the model to M31 is presented.

  17. Microscopic spin dephasing and magnetization relaxation in an s-d model

    NASA Astrophysics Data System (ADS)

    Schneider, Hans Christian; Baral, Alexander

    2014-03-01

    We calculate the spin dynamics in a model of itinerant carriers coupled antiferromagnetically to a macrospin (''s-d model''). The dephasing comes in via the coupling to a phonon bath in the presence of spin-orbit coupling, which we take to be of the Bychkov-Rashba type. Using a mean-field approximation for the s-d model with an antiferromagnetic exchange coupling, we derive Boltzmann scattering integrals for itinerant-carrier spin density matrix, i.e., for the distributions and spin coherences. The spin density matrix is needed because of a constant change of the longitudinal and transverse directions during the coupled dynamics of the itinerant spins and the macrospin. Due to the Rashba spin-orbit coupling, the resulting model describes a form of Elliot-Yafet type carrier-spin relaxation due to electron-phonon scattering within an equation-of-motion formalism. We extrapolate dephasing- and magnetization times T1 and T2 and draw a comparison to phenomenological equations such as the Landau-Lifshitz or Landau-Lifshitz Gilbert equations. We then analyze the magnetization precession and relaxation of the coupled carrier spins and macrospin in an anisotropy field, and find a carrier mediated dephasing of the macrospin via mean-field

  18. Narrowing of the neutron sd- pf shell gap in 29Na

    NASA Astrophysics Data System (ADS)

    Hurst, A. M.; Wu, C. Y.; Becker, J. A.; Stoyer, M. A.; Pearson, C. J.; Hackman, G.; Schumaker, M. A.; Svensson, C. E.; Austin, R. A. E.; Ball, G. C.; Bandyopadhyay, D.; Barton, C. J.; Boston, A. J.; Boston, H. C.; Churchman, R.; Cline, D.; Colosimo, S. J.; Cross, D. S.; Demand, G.; Djongolov, M.; Drake, T. E.; Garrett, P. E.; Gray-Jones, C.; Green, K. L.; Grint, A. N.; Hayes, A. B.; Leach, K. G.; Kulp, W. D.; Lee, G.; Lloyd, S.; Maharaj, R.; Martin, J.-P.; Millar, B. A.; Mythili, S.; Nelson, L.; Nolan, P. J.; Oxley, D. C.; Padilla-Rodal, E.; Phillips, A. A.; Porter-Peden, M.; Rigby, S. V.; Sarazin, F.; Sumithrarachchi, C. S.; Triambak, S.; Walker, P. M.; Williams, S. J.; Wong, J.; Wood, J. L.

    2009-04-01

    The wave-function composition for the low-lying states in 29Na was explored by measuring their electromagnetic properties using the Coulomb-excitation technique. A beam of 29Na ions, postaccelerated to 70 MeV, bombarded a 110Pd target with a rate of up to 600 particles per second at the recently commissioned ISAC-II facility at TRIUMF. Six segmented HPGe clover detectors of the TIGRESS γ-ray spectrometer were used to detect deexcitation γ rays in coincidence with scattered or recoiling charged particles in the segmented silicon detector, BAMBINO. The reduced transition matrix element | <5/2 1 + | | E 2 | |3/2 gs + > | in 29Na was derived to be 0.237(21) e b from the measured γ-ray yields for both projectile and target. This first-time measured value is consistent with the most recent Monte Carlo shell-model calculation, indicating a significant admixture of both sd and pf components in the wave function, and also providing evidence for the narrowing of the neutron sd- pf shell gap from ∼ 6 MeV for stable nuclei to ∼ 3 MeV for 29Na.

  19. The role of glutathione detoxification pathway in MCLR-induced hepatotoxicity in SD rats.

    PubMed

    Li, Shangchun; Chen, Jun; Xie, Ping; Guo, Xiaochun; Fan, Huihui; Yu, Dezhao; Zeng, Cheng; Chen, Liang

    2015-12-01

    In the present study, we investigated the role of glutathione (GSH) and its related enzymes in Sprague Dawley (SD) rats subjected to microcystin-leucine-arginine (MCLR)-induced hepatotoxicity. SD rats were intraperitoneally (i.p.) injected with MCLR after pretreating with or without buthionine-(S,R)-sulfoximine (BSO), an inhibitor of GSH synthesis. The depletion of GSH with BSO enhanced MCLR-induced oxidative stress, resulting in more severe liver damage and higher MCLR accumulation. Similarly, the contents of malondialdehyde (MDA), total GSH (T-GSH), oxidized GSH (GSSG) and GSH were significantly enhanced in BSO pretreated rats following MCLR treatment. The study showed that the transcription of GSH-related enzymes such as glutathione-S-transferase (GST), γ-glutamylcysteine synthetase (γ-GCS), glutathione reductase (GR) varied in different ways (expect for glutathione peroxidase (GPx), whose gene expression was induced in all treated groups) with or without BSO pretreatment before MCLR exposure, suggesting an adaptative response of GSH-related enzymes at transcription level to combat enhancement of oxidative stress induced by MCLR when pretreated with BSO. These data suggested the tissues with low GSH concentration are highly vulnerable to MCLR toxicity and GSH was critical for the detoxification in MCLR-induced hepatotoxicity in vivo.

  20. A framework for classification and segmentation of branch retinal artery occlusion in SD-OCT

    NASA Astrophysics Data System (ADS)

    Guo, Jingyun; Shi, Fei; Zhu, Weifang; Chen, Haoyu; Chen, Xinjian

    2016-03-01

    Branch retinal artery occlusion (BRAO) is an ocular emergency which could lead to blindness. Quantitative analysis of BRAO region in the retina is very needed to assessment of the severity of retinal ischemia. In this paper, a fully automatic framework was proposed to classify and segment BRAO based on 3D spectral-domain optical coherence tomography (SD-OCT) images. To the best of our knowledge, this is the first automatic 3D BRAO segmentation framework. First, a support vector machine (SVM) based classifier is designed to differentiate BRAO into acute phase and chronic phase, and the two types are segmented separately. To segment BRAO in chronic phase, a threshold-based method is proposed based on the thickness of inner retina. While for segmenting BRAO in acute phase, a two-step segmentation is performed, which includes the bayesian posterior probability based initialization and the graph-search-graph-cut based segmentation. The proposed method was tested on SD-OCT images of 23 patients (12 of acute and 11 of chronic phase) using leave-one-out strategy. The overall classification accuracy of SVM classifier was 87.0%, and the TPVF and FPVF for acute phase were 91.1%, 5.5%; for chronic phase were 90.5%, 8.7%, respectively.

  1. FUV, UV, and Optical Observations of the He-sdO Star BD+39 3226

    NASA Astrophysics Data System (ADS)

    Chayer, Pierre; Green, E. M.; Fontaine, G.

    2014-01-01

    Based on observations carried out with the Far Ultraviolet Spectroscopic Explorer, the Space Telescope Imaging Spectrograph, the MMT Observatory, and the Keck telescope HIRES spectrograph, we present a spectral analysis of the He-sdO star BD+39 3226. By fitting the MMT spectrum we obtain a gravity that is 0.7 dex higher than the one reported in the literature. The new atmospheric parameters will have an impact on the measurement of the HI column density toward BD+39 3226, and by this very fact on the deuterium abundance. The high-resolution spectra show stellar absorption lines coming from C, N, O, Si, P, S, Fe, and Ni. The spectra also show lines from heavy elements such as Ge, As, and Sn. On the other hand, neither Zr nor Pb absorption lines are detected. The non-detection of lead in BD+39 3226 indicates that the star does not belong to the newly discovered group of lead-rich He-sdO stars. P.C. is supported by the Canadian Space Agency under a Public Works and Government Services of Canada contract.

  2. Geology of the USW SD-9 drill hole, Yucca Mountain, Nevada

    SciTech Connect

    Engstrom, D.A.; Rautman, C.A.

    1996-10-01

    Drill hole USW SD-9 is one of several holes drilled under Site Characterization Plan Study as part of the characterization program at Yucca Mountain, Nevada, which has been proposed as the potential location of a repository for high-level nuclear waste. The SD-9 drill hole is located in the northern part of the potential repository area. Quantitative and semiquantitative data are included in this report for cover recovery, rock-quality designation (RQD), lithophysal cavity abundance, and fracturing. These data are spatially variable, both within and among the major formational-level stratigraphic units. Nonwelded intervals in general exhibit higher recoveries and more intact (higher) RQD values than welded intervals. The most intact, highest-RQD materials encountered within the Topopah Spring belong to the lower 33.3 ft of the middle nonlithophysal zone. This report includes quantitative data for the framework material properties of porosity, bulk and particle density, and saturated hydraulic conductivity. Graphical analysis of variations in these laboratory hydrologic properties indicates first-order control of material properties by the degree of welding and the presence of zeolite minerals. Many major lithostratigraphic contacts are not well expressed in the material-property profiles; contacts of material-property units are related more to changes in the intensity of welding. Approximate in-situ saturation data of samples preserved immediately upon recovery from the hole are included in the data tabulation.

  3. Secondary metabolites from Penicillium pinophilum SD-272, a marine sediment-derived fungus.

    PubMed

    Wang, Ming-Hui; Li, Xiao-Ming; Li, Chun-Shun; Ji, Nai-Yun; Wang, Bin-Gui

    2013-06-01

    Two new secondary metabolites, namely, pinodiketopiperazine A (1) and 6,7-dihydroxy-3-methoxy-3-methylphthalide (2), along with alternariol 2,4-dimethyl ether (3) and L-5-oxoproline methyl ester (4), which were isolated from a natural source for the first time but have been previously synthesized, were characterized from the marine sediment-derived fungus Penicillium pinophilum SD-272. In addition, six known metabolites (5-10) were also identified. Their structures were elucidated by analysis of the NMR and mass spectroscopic data. The absolute configuration of compound 1 was determined by experimental and calculated ECD spectra. Compound 2 displayed potent brine shrimp (Artemia salina) lethality with LD₅₀ 11.2 μM. PMID:23792827

  4. Absolute density measurement of SD radicals in a supersonic jet at the quantum-noise-limit.

    PubMed

    Mizouri, Arin; Deng, L Z; Eardley, Jack S; Nahler, N Hendrik; Wrede, Eckart; Carty, David

    2013-12-01

    The absolute density of SD radicals in a supersonic jet has been measured down to (1.1 ± 0.1) × 10(5) cm(-3) in a modestly specified apparatus that uses a cross-correlated combination of cavity ring-down and laser-induced fluorescence detection. Such a density corresponds to 215 ± 21 molecules in the probe volume at any given time. The minimum detectable absorption coefficient was quantum-noise-limited and measured to be (7.9 ± 0.6) × 10(-11) cm(-1), in 200 s of acquisition time, corresponding to a noise-equivalent absorption sensitivity for the apparatus of (1.6 ± 0.1) × 10(-9) cm(-1) Hz(-1/2).

  5. Support vector machine based IS/OS disruption detection from SD-OCT images

    NASA Astrophysics Data System (ADS)

    Wang, Liyun; Zhu, Weifang; Liao, Jianping; Xiang, Dehui; Jin, Chao; Chen, Haoyu; Chen, Xinjian

    2014-03-01

    In this paper, we sought to find a method to detect the Inner Segment /Outer Segment (IS/OS)disruption region automatically. A novel support vector machine (SVM) based method was proposed for IS/OS disruption detection. The method includes two parts: training and testing. During the training phase, 7 features from the region around the fovea are calculated. Support vector machine (SVM) is utilized as the classification method. In the testing phase, the training model derived is utilized to classify the disruption and non-disruption region of the IS/OS, and calculate the accuracy separately. The proposed method was tested on 9 patients' SD-OCT images using leave-one-out strategy. The preliminary results demonstrated the feasibility and efficiency of the proposed method.

  6. Isospin Symmetry Along The N=Z Line In The sd Shell

    SciTech Connect

    Della Vedova, F.; Lenzi, S. M.; Farnea, E.; Nespolo, M.; Bazzacco, D.; Brandolini, F.; Lunardi, S.; Menegazzo, R.; Rossi Alvarez, C.; Ur, C.A.; Ionescu-Bujor, M.; Bucurescu, D.; Iordachescu, A.; Marginean, N.; De Angelis, G.; Axiotis, M.; Napoli, D. R.; Bizzeti-Sona, A.; Bizzeti, P.G.

    2005-04-05

    Excited states have been studied in sd-shell nuclei following the 16O (70 MeV) + 24Mg (400 {mu}g/cm2) fusion-evaporation reaction. The GASP spectrometer in conjunction with the charged-particle detector ISIS and the Neutron ring allowed the detection of the {gamma}-rays in coincidence with evaporated light particles. New data on the mirror pairs A=31 and A=35 have been obtained. In particular, the comparison between the level schemes of 35Ar and 35Cl has confirmed the importance of the electromagnetic spin-orbit term, which explains the large Mirror Energy Difference values. Evidence of isospin mixing can be deduced from the E1 transitions.

  7. Rate tables for the weak processes of sd-shell nuclei in stellar matter

    SciTech Connect

    Oda, Takeshi; Hino, Masayuki; Muto, Kazuo ); Takahara, Mariko ); Sato, Katsuhiko )

    1994-03-01

    The weak interaction rates in stellar matter are calculated for the sd-shell nuclei in the full-shell model configurations using the effective interaction of Wildenthal, taking into account the recent extensive compilations of experimental energy levels and Gamow-Teller [beta] decay rates. Based on comparisons between the present calculation and that of Fuller, Fowler, and Newman (FFN), it is pointed out that correct treatment of nuclear structure effects is decisive in attaining reliable weak interaction rates in stellar matter. The weak rates are tabulated at the same grid points of density and temperature as those of FFN, for the ranges 10 [le] pY[sub e] (g[center dot]cm[sup [minus]3]) [le] 10[sup 11] and 0.01 [times] 10[sup 9] [le] T (K) [le] 30 [times] 10[sup 9]. 33 refs., 3 figs., 2 tabs.

  8. Electrical Characterization of the RCA CDP1822SD Random Access Memory, Volume 1, Appendix a

    NASA Technical Reports Server (NTRS)

    Klute, A.

    1979-01-01

    Electrical characteristization tests were performed on 35 RCA CDP1822SD, 256-by-4-bit, CMOS, random access memories. The tests included three functional tests, AC and DC parametric tests, a series of schmoo plots, rise/fall time screening, and a data retention test. All tests were performed on an automated IC test system with temperatures controlled by a thermal airstream unit. All the functional tests, the data retention test, and the AC and DC parametric tests were performed at ambient temperatures of 25 C, -20 C, -55 C, 85 C, and 125 C. The schmoo plots were performed at ambient temperatures of 25 C, -55 C, and 125 C. The data retention test was performed at 25 C. Five devices failed one or more functional tests and four of these devices failed to meet the expected limits of a number of AC parametric tests. Some of the schmoo plots indicated a small degree of interaction between parameters.

  9. Source identification in acoustics and structural mechanics using Sierra/SD.

    SciTech Connect

    Walsh, Timothy Francis; Aquino, Wilkins; Ross, Michael

    2013-03-01

    In this report we derive both time and frequency-domain methods for inverse identification of sources in elastodynamics and acoustics. The inverse/design problem is cast in a PDE-constrained optimization framework with efficient computation of gradients using the adjoint method. The implementation of source inversion in Sierra/SD is described, and results from both time and frequency domain source inversion are compared to actual experimental data for a weapon store used in captive carry on a military aircraft. The inverse methodology is advantageous in that it provides a method for creating ground based acoustic and vibration tests that can reduce the actual number of flight tests, and thus, saving costs and time for the program.

  10. Lactogenic Activity of an Enzymatic Hydrolysate from Octopus vulgaris and Carica papaya in SD Rats.

    PubMed

    Cai, Bingna; Chen, Hua; Sun, Han; Sun, Huili; Wan, Peng; Chen, Deke; Pan, Jianyu

    2015-11-01

    The traditional Chinese medicine theory believes that octopus papaya soup can stimulate milk production in lactating women. The objective of this study was to determine whether dietary supplementation with an enzymatic hydrolysate of Octopus vulgaris and Carica papaya (EHOC) could increase milk production and nutritional indexes in Sprague Dawley (SD) rats. Female SD rats (n = 24) were fed a control diet (n = 8), EHOC-supplemented diet, or a positive control diet (Shengruzhi) from day 10 of pregnancy to day 10 of lactation. Maternal serum, mammary gland (day 10 of lactation), milk, and pup weight (daily) were collected for analysis. Results showed that the EHOC diet obviously elevated daily milk yield and pup weight compared to the control group (P < .05). The EHOC diet was found to increase the concentration of prolactin (PRL), progesterone (P), estradiol (E2), and growth hormone (GH) significantly in the circulation and mammary gland. Mammary glands of EHOC-treated dams showed clear lobuloalveolar development and proliferation of myoepithelial cells, but no striking variations were observed among the groups. Furthermore, the nutrition content and immune globulin concentration in the milk of EHOC-supplemented dams were higher than those of the control group, especially the cholesterol, glucose, and IgG were higher by 44.98% (P < .001), 42.76% (P < .01), and 42.23% (P < .01), respectively. In conclusion, this article demonstrates that EHOC administration has beneficial effects on milk production in the dams and on performance of the dam and pup. These results indicate that EHOC could be explored as a potentially lactogenic nutriment for lactating women. PMID:26270883

  11. Lactogenic Activity of an Enzymatic Hydrolysate from Octopus vulgaris and Carica papaya in SD Rats.

    PubMed

    Cai, Bingna; Chen, Hua; Sun, Han; Sun, Huili; Wan, Peng; Chen, Deke; Pan, Jianyu

    2015-11-01

    The traditional Chinese medicine theory believes that octopus papaya soup can stimulate milk production in lactating women. The objective of this study was to determine whether dietary supplementation with an enzymatic hydrolysate of Octopus vulgaris and Carica papaya (EHOC) could increase milk production and nutritional indexes in Sprague Dawley (SD) rats. Female SD rats (n = 24) were fed a control diet (n = 8), EHOC-supplemented diet, or a positive control diet (Shengruzhi) from day 10 of pregnancy to day 10 of lactation. Maternal serum, mammary gland (day 10 of lactation), milk, and pup weight (daily) were collected for analysis. Results showed that the EHOC diet obviously elevated daily milk yield and pup weight compared to the control group (P < .05). The EHOC diet was found to increase the concentration of prolactin (PRL), progesterone (P), estradiol (E2), and growth hormone (GH) significantly in the circulation and mammary gland. Mammary glands of EHOC-treated dams showed clear lobuloalveolar development and proliferation of myoepithelial cells, but no striking variations were observed among the groups. Furthermore, the nutrition content and immune globulin concentration in the milk of EHOC-supplemented dams were higher than those of the control group, especially the cholesterol, glucose, and IgG were higher by 44.98% (P < .001), 42.76% (P < .01), and 42.23% (P < .01), respectively. In conclusion, this article demonstrates that EHOC administration has beneficial effects on milk production in the dams and on performance of the dam and pup. These results indicate that EHOC could be explored as a potentially lactogenic nutriment for lactating women.

  12. SAMI3/SD-WACCM-X simulations of ionospheric variability during northern winter 2009

    NASA Astrophysics Data System (ADS)

    McDonald, S. E.; Sassi, F.; Mannucci, A. J.

    2015-09-01

    We have performed simulations using the Naval Research Laboratory's physics-based model of the ionosphere, Sami3 is A Model of the Ionosphere (SAMI3), to illustrate how neutral wind dynamics is responsible for day-to-day variability of the ionosphere. We have used neutral winds specified from the extended version of the specified dynamics Whole Atmosphere Community Climate Model (SD-WACCM-X), in which meteorology below 92 km is constrained by atmospheric specifications from an operational weather forecast model and reanalysis. To assess the realism of the simulations against observations, we have carried out a case study during January-February 2009, a dynamically disturbed time characterized by a sudden stratospheric warming (SSW) commencing 24 January 2009. Model results are compared with total electron content (TEC) from Jet Propulsion Laboratory global ionospheric maps. We show that SAMI3/SD-WACCM-X captures longitudinal variability in the equatorial ionization anomaly associated with nonmigrating tides, with strongest contributions coming from the diurnal eastward wave number 2 (DE2) and DE3. Both migrating and nonmigrating tides contribute to significant day-to-day variability, with TEC varying up to 16%. Our simulation during the SSW period reveals that at the Jicamarca longitude (285°E) on 27 January 2009 nonmigrating tides contribute to an enhancement of the electron density in the morning followed by a decrease in the afternoon. An enhancement of the semidiurnal eastward wave number 2 (SE2) and SE3 nonmigrating tides, likely associated with the appearance of the SSW, suggests that these tides increase the longitudinal variability of the SSW impact on the ionosphere. The conclusion is that realistic meteorology propagating upward from the lower atmosphere influences the dynamo region and reproduces aspects of the observed variability in the ionosphere.

  13. Local Variability of Macular Thickness Measurements With SD-OCT and Influencing Factors

    PubMed Central

    Miraftabi, Arezoo; Amini, Navid; Gornbein, Jeff; Henry, Sharon; Romero, Pablo; Coleman, Anne L.; Caprioli, Joseph; Nouri-Mahdavi, Kouros

    2016-01-01

    Purpose To compare the intrasession variability of spectral-domain optical coherence tomography (SD-OCT)-derived local macular thickness measures and explore influencing factors. Methods One hundred two glaucomatous eyes (102 patients) and 21 healthy eyes (21 subjects) with three good quality macular images during the same session were enrolled. Thickness measurements were calculated for 3° superpixels for the inner plexiform (IPL), ganglion cell (GCL), or retinal nerve fiber layers (mRNFL), GC/IPL, ganglion cell complex, and full macular thickness. Spatial distribution and magnitude of measurement errors (ME; differences between the 3 individual superpixel values and their mean) and association between MEs and thickness, age, axial length, and image quality were explored. Results MEs had a normal distribution with mostly random noise along with a small fraction of outliers (1.2%–6.6%; highest variability in mRNFL and on the nasal border) based on M-estimation. Boundaries of 95% prediction intervals for variability reached a maximum of 3 μm for all layers and diagnostic groups after exclusion of outliers. Correlation between proportion of outliers and thickness measures varied among various parameters. Age, axial length, or image quality did not influence MEs (P > 0.05 for both groups). Conclusions Local variability of macular SD-OCT measurements is low and uniform across the macula. The relationship between superpixel thickness and outlier proportion varied as a function of the parameter of interest. Translational Relevance Given the low and uniform variability within and across eyes, definition of an individualized ‘variability space' seems unnecessary. The variability measurements from this study could be used for designing algorithms for detection of glaucoma progression. PMID:27486555

  14. Does repetitive Ritalin injection produce long-term effects on SD female adolescent rats?

    PubMed

    Lee, Min J; Yang, Pamela B; Wilcox, Victor T; Burau, Keith D; Swann, Alan C; Dafny, Nachum

    2009-09-01

    Methylphenidate (MPD), or Ritalin, is a psychostimulant that is prescribed for an extended period of time to children and adolescents with attention deficit hyperactivity disorder. Adolescence is a time of critical brain maturation and development, and the drug exposure during this time could lead to lasting changes in the brain that endure into the adulthood. Circadian rhythms are 24 h rhythms of physiological processes that are synchronized by the master-clock, the suprachiasmatic nucleus, to keep the body stable in a changing environment. The aim of present study is to observe the effect of repeated MPD exposure on the locomotor diurnal rhythm activity patterns of female adolescent Sprague-Dawley (SD) rats using the open field assay. 31 female adolescent SD rats were divided into four groups: control, 0.6 mg/kg, 2.5 mg/kg, and 10 mg/kg MPD group. On experimental day 1, all groups were given an injection of saline. On experimental days 2-7, animals were injected once a day with either saline, 0.6 mg/kg, 2.5 mg/kg, or 10 mg/kg MPD, and experimental days 8-10 were the washout period. A re-challenge injection was given to each animal on experimental day 11 with the similar dose as the experimental days 2-7. The locomotor movements were counted by the computerized animal activity monitoring system. The data were analyzed statistically to find out whether the diurnal rhythm activity patterns were altered. The obtained data showed that repeated administrations of 2.5 mg/kg and 10 mg/kg MPD were able to change the locomotor diurnal rhythm patterns, which suggests that these MPD doses exerts long-term effects.

  15. [Bone bank management using a thermal disinfection system (Lobator SD-1). A critical analysis].

    PubMed

    Hofmann, C; von Garrel, T; Gotzen, L

    1996-07-01

    In the study presented on 380 allogenic bone donations from living and organ donors, we analyzed the safety of allograft handling bone-band documentation, logistics and costs. For transplant treatment we routinely used a thermal disinfection system (Lobator SD-1). From 380 allograft donors, 400 bone transplants were gained. The rejection rate was 12.2%. After thermal disinfection for 1 h at 80 degrees C, the grafts were cryopreserved at -80 degrees C and released from the bone bank for potential transplantation after 14-16 days. Five of 730 microbiological specimens showed bacterial contamination after thermal graft decontamination. The bacterial species found on the allografts normally have an inactivation temperature under 80 degrees C. Therefore, only secondary contamination can explain the positive bacteriological test results. With reform of the health care system the economical aspects of bone banking have triggered more interest. The cost for one bone transplant released from the bone bank was 424.75 DM: the overall cost for the bone bank in one year was 75,076 DM. Laboratory (58.2%) and material costs (22.5%) were the major factors. Personnel costs and apparatus costs were relatively low (< 20%). With introduction of the thermal disinfection system (Lobator SD-1) into the bone bank, the safety of allogenic bone transplants was greatly improved. Clinical and serological donor screening must be performed according to international bone bank directives. Considering the low rejection rate and the short turnover rate, the economical costs could be reduced. Using an appropriate disinfection system (thermal disinfection at 80 degrees C), laboratory tests covering venereal diseases, malaria and cytomegalia are no longer required. Also, secondary HIV testing of living donors can be omitted without reducing the safety of the transplant.

  16. THE ROMER DELAY AND MASS RATIO OF THE sdB+dM BINARY 2M 1938+4603 FROM KEPLER ECLIPSE TIMINGS

    SciTech Connect

    Barlow, Brad N.; Wade, Richard A.; Liss, Sandra E.

    2012-07-10

    The eclipsing binary system 2M 1938+4603 consists of a pulsating hot subdwarf B star and a cool M dwarf companion in an effectively circular three-hour orbit. The light curve shows both primary and secondary eclipses, along with a strong reflection effect from the cool companion. Here, we present constraints on the component masses and eccentricity derived from the Romer delay of the secondary eclipse. Using six months of publicly available Kepler photometry obtained in short-cadence mode, we fit model profiles to the primary and secondary eclipses to measure their centroid values. We find that the secondary eclipse arrives on average 2.06 {+-} 0.12 s after the midpoint between primary eclipses. Under the assumption of a circular orbit, we calculate from this time delay a mass ratio of q = 0.2691 {+-} 0.0018 and individual masses of M{sub sd} = 0.372 {+-} 0.024 M{sub Sun} and M{sub c} = 0.1002 {+-} 0.0065 M{sub Sun} for the sdB and M dwarf, respectively. These results differ slightly from those of a previously published light-curve modeling solution; this difference, however, may be reconciled with a very small eccentricity, ecos {omega} Almost-Equal-To 0.00004. We also report a decrease in the orbital period of P-dot = (-1.23 {+-} 0.07) Multiplication-Sign 10{sup -10}.

  17. Important operational parameters of membrane bioreactor-sludge disintegration (MBR-SD) system for zero excess sludge production.

    PubMed

    Yoon, Seong-Hoon

    2003-04-01

    In order to prevent excess sludge production during wastewater treatment, a membrane bioreactor-sludge disintegration (MBR-SD) system has been introduced, where the disintegrated sludge is recycled to the bioreactor as a feed solution. In this study, a mathematical model was developed by incorporating a sludge disintegration term into the conventional activated sludge model and the relationships among the operational parameters were investigated. A new definition of F/M ratio for the MBR-SD system was suggested to evaluate the actual organic loading rate. The actual F/M ratio was expected to be much higher than the apparent F/M ratio in MBR-SD. The kinetic parameters concerning the biodegradability of organics hardly affect the system performance. Instead, sludge solubilization ratio (alpha) in the SD process and particulate hydrolysis rate constant (k(h)) in biological reaction determine the sludge disintegration number (SDN), which is related with the overall economics of the MBR-SD system. Under reasonable alpha and k(h) values, SDN would range between 3 and 5 which means the amount of sludge required to be disintegrated would be 3-5 times higher for preventing a particular amount of sludge production. Finally, normalized sludge disintegration rate (q/V) which is needed to maintain a certain level of MLSS in the MBR-SD system was calculated as a function of F/V ratio.

  18. Negative Segregation Distortion in the Sd System of Drosophila Melanogaster: A Challenge to the Concept of Differential Sensitivity of Rsp Alleles

    PubMed Central

    Hiraizumi, Y.

    1990-01-01

    Current models of segregation distortion based on previous experimental results predict that, in the Sd heterozygous Rsp(i)/Rsp(s) male, the chromosome carrying the sensitive Rsp(s) allele is distorted or transmitted in a frequency smaller than that of the expected Mendelian 0.5 relative to the chromosome carrying the insensitive Rsp(i) allele. The present study presents a case where this does not occur, that is, when the genotype of the males is supp-X(SD)/Y; Sd E(SD)Rsp(i) M(SD)(+)/Sd(+) E(SD)(+) Rsp(s) M(SD)(+) where supp-X(SD) is an X chromosome carrying a strong suppressor or suppressors of SD activity and SD(+) E(SD)(+) Rsp(s) M(SD)(+) is the standard cn bw chromosome. Following the ``inseminated female transfer'' procedure, young males of the above genotype carrying the standard-X instead of the supp-X(SD) chromosome show k values for the SD chromosome (frequencies of the SD chromosome recovered among progeny) of about 0.75, but with the supp-X(SD) chromosome, the k values are reduced to 0.36-0.41. Several possibilities other than the mechanism of segregation distortion to explain the reduced k values are ruled out. The occurrence of ``negative segregation distortion'' is clearly demonstrated, where the chromosome carrying the Rsp(i) allele is distorted, but the chromosome with the Rsp(s) allele is not. This result requires a major modification of the current models or even a new model for the mechanism of segregation distortion to accommodate Rsp allele sensitivity or insensitivity. The present study also shows that males of the genotype, Sd Rsp(ss) M(SD)(+)/Sd(+) Rsp(ss) M(SD), are almost completely sterile, but their fertility is considerably increased when SD activity is suppressed by the presence of the supp-X(SD) chromosome. This result suggests that the amount of the Sd product is not limited with respect to the interacting sites available, that is, the amount is large enough to interact with both of the Rsp(ss) alleles. PMID:2116354

  19. Finite element modeling tests of the seven moment tensor approximation of ground displacement from tri-axial pressurized ellipsoids.

    NASA Astrophysics Data System (ADS)

    Luongo, Annamaria; Amoruso, Antonella; Crescentini, Luca

    2015-04-01

    Volcanic unrests can be studied through the induced surface deformation; one limiting factor however is the small number of available deformation source models. Till 2011, the only available (approximate or exact) expressions for finite expansion sources referred to spheres, prolate spheroids, and horizontal circular cracks embedded in a homogeneous half-space. Cervelli (2013) derived more general approximate expressions for displacement from a finite spheroid of arbitrary orientation and aspect ratio, embedded in a homogeneous half-space. The only approximate expressions for displacements and stresses from the inflation of a finite pressurized tri-axial ellipsoid in a (possibly heterogeneous) half-space were published by Amoruso and Crescentini (2011). Starting from the equivalence (exact for an infinite elastic medium) between the external displacement field due to a pressurized ellipsoidal cavity and the displacement field given by a uniform distribution of seismic moments, Amoruso and Crescentini (2011) accounted for source finiteness by using an approach similar to the multipole expansion of the gravitational potential outside a mass distribution. The dipole term is null because of symmetry; terms to quadrupole order are kept. The resulting expressions can be evaluated by combining the effects of seven moment tensors (SMT model) and are approximately valid also for a heterogeneous half-space. In case of a layered half-space, the appropriate displacement Green functions can be evaluated analitically and the SMT model has already been used to invert ground deformation data of the Campi Flegrei Caldera, Italy. In case of a heterogeneous medium, the appropriate displacement Green functions can be computed, once and for all, using FEM, so that the SMT model still allows fast forward computations and can be included into inversion codes. Amoruso and Crescentini (2011) could test the goodness of their approach only in case of spherical and prolate spheroidal cavities

  20. Tri-Axial Accelerometer-Determined Daily Physical Activity and Sedentary Behavior of Suburban Community-Dwelling Older Japanese Adults

    PubMed Central

    Chen, Tao; Narazaki, Kenji; Honda, Takanori; Chen, Sanmei; Haeuchi, Yuki; Nofuji, Yu Y; Matsuo, Eri; Kumagai, Shuzo

    2015-01-01

    Knowledge regarding accelerometer-derived physical activity (PA) and sedentary behavior (SED) levels is scarce for Japanese older adults. The aims of this study were therefore to 1) describe levels of PA and SED in Japanese community-dwelling older adults, using tri-axial accelerometer; 2) examine the variation of PA and SED with respect to sex, age, and body mass index (BMI). Participants of this study were from the baseline survey of the Sasaguri Genkimon Study, who were 65 years or older and not certified as those requiring long-term care. PA was assessed objectively for seven consecutive days using tri-axial accelerometer. A total of 1,739 participants (median age: 72 years, men: 38.0%) with valid PA data were included. Overall, participants in the present study spent 54.5% of their waking time being sedentary and 45.5% being active, of which 5.4% was moderate-to-vigorous physical activity (MVPA). Women accumulated more minutes of light physical activity (LPA) and MVPA compared with men. In contrast, men spent more time being sedentary. Mean steps per day did not differ between sexes. Furthermore, participants with higher BMI (BMI ≥25) had lower PA levels, and longer SED compared with those with lower BMI (BMI <). PA levels were lower and SED was longer with age. The present study is the first to demonstrate that the levels of PA and SED differed by sex, age, and BMI in Japanese community-dwelling older adults. In particular, women were more active compared with men, providing unique insight into the current level of PA in older adults. Data presented in the study will enable further investigation of additional determinants of PA and SED in order to develop effective population-based intervention strategies to promote PA and reduce prolonged SED in the Japanese population and possibly other rapidly aging societies. Key points Accelerometer, that is capable to assess PA more precisely in large scale epidemiological studies, provides opportunity for improving

  1. Physical properties of the ESA Rosetta target asteroid (21) Lutetia. I. The triaxial ellipsoid dimensions, rotational pole, and bulk density

    NASA Astrophysics Data System (ADS)

    Drummond, J. D.; Conrad, A.; Merline, W. J.; Carry, B.; Chapman, C. R.; Weaver, H. A.; Tamblyn, P. M.; Christou, J. C.; Dumas, C.

    2010-11-01

    Context. Asteroid (21) Lutetia was the target of the ESA Rosetta mission flyby in 2010 July. Aims: We seek the best size estimates of the asteroid, the direction of its spin axis, and its bulk density, assuming its shape is well described by a smooth featureless triaxial ellipsoid. We also aim to evaluate the deviations from this assumption. Methods: We derive these quantities from the outlines of the asteroid in 307 images of its resolved apparent disk obtained with adaptive optics (AO) at Keck II and VLT, and combine these with recent mass determinations to estimate a bulk density. Results: Our best triaxial ellipsoid diameters for Lutetia, based on our AO images alone, are a × b × c = 132 × 101 × 93 km, with uncertainties of 4 × 3 × 13 km including estimated systematics, with a rotational pole within 5° of ECJ2000 [λβ] = [45° - 7°] , or EQJ2000 [RA Dec] = [44° + 9°] . The AO model fit itself has internal precisions of 1 × 1 × 8 km, but it is evident both from this model derived from limited viewing aspects and the radius vector model given in a companion paper, that Lutetia significantly departs from an idealized ellipsoid. In particular, the long axis may be overestimated from the AO images alone by about 10 km. Therefore, we combine the best aspects of the radius vector and ellipsoid model into a hybrid ellipsoid model, as our final result, of diameters 124 ± 5 × 101 ± 4 × 93 ± 13 km that can be used to estimate volumes, sizes, and projected areas. The adopted pole position is within 5° of [λβ] = [52° - 6°] or [RA Dec] = [52° + 12°]. Conclusions: Using two separately determined masses and the volume of our hybrid model, we estimate a density of 3.5±1.1 or 4.3±0.8 g cm-3. From the density evidence alone, we argue that this favors an enstatite-chondrite composition, although other compositions are formally allowed at the extremes (low-porosity CV/CO carbonaceous chondrite or high-porosity metallic). We discuss this in the context of

  2. Configuration mixing of angular-momentum-projected triaxial relativistic mean-field wave functions. II. Microscopic analysis of low-lying states in magnesium isotopes

    SciTech Connect

    Yao, J. M.; Mei, H.; Chen, H.; Meng, J.; Ring, P.; Vretenar, D.

    2011-01-15

    The recently developed structure model that uses the generator coordinate method to perform configuration mixing of angular-momentum projected wave functions, generated by constrained self-consistent relativistic mean-field calculations for triaxial shapes (3DAMP+GCM), is applied in a systematic study of ground states and low-energy collective states in the even-even magnesium isotopes {sup 20-40}Mg. Results obtained using a relativistic point-coupling nucleon-nucleon effective interaction in the particle-hole channel and a density-independent {delta} interaction in the pairing channel are compared to data and with previous axial 1DAMP+GCM calculations, both with a relativistic density functional and the nonrelativistic Gogny force. The effects of the inclusion of triaxial degrees of freedom on the low-energy spectra and E2 transitions of magnesium isotopes are examined.

  3. Investigation of the interface characteristics of Y2O3/GaAs under biaxial strain, triaxial strain, and non-strain conditions

    NASA Astrophysics Data System (ADS)

    Shi, Li-Bin; Liu, Xu-Yang; Dong, Hai-Kuan

    2016-09-01

    We investigate the interface behaviors of Y2O3/GaAs under biaxial strain, triaxial strain, and non-strain conditions. This study is performed by first principles calculations based on density functional theory (DFT). First of all, the biaxial strain is realized by changing the lattice constants in ab plane. Averaged electrostatic potential (AEP) is aligned by establishing Y2O3 and GaAs (110) surfaces. The band offsets of Y2O3/GaAs interface under biaxial strain are investigated by generalized gradient approximation and Heyd-Scuseria-Ernzerhof (HSE) functionals. The interface under biaxial strain is suitable for the design of metal oxide semiconductor (MOS) devices because the valence band offsets (VBO) and conduction band offsets (CBO) are larger than 1 eV. Second, the triaxial strain is applied to Y2O3/GaAs interface by synchronously changing the lattice constants in a, b, and c axis. The band gaps of Y2O3 and GaAs under triaxial strain are investigated by HSE functional. We compare the VBO and CBO under triaxial strain with those under biaxial strain. Third, in the absence of lattice strain, the formation energies, charge state switching levels, and migration barriers of native defects in Y2O3 are assessed. We investigate how they will affect the MOS device performance. It is found that VO+2 and Oi-2 play a very dangerous role in MOS devices. Finally, a direct tunneling leakage current model is established. The model is used to analyze current and voltage characteristics of the metal/Y2O3/GaAs.

  4. Vector magnetometer design study: Analysis of a triaxial fluxgate sensor design demonstrates that all MAGSAT Vector Magnetometer specifications can be met

    NASA Technical Reports Server (NTRS)

    Adams, D. F.; Hartmann, U. G.; Lazarow, L. L.; Maloy, J. O.; Mohler, G. W.

    1976-01-01

    The design of the vector magnetometer selected for analysis is capable of exceeding the required accuracy of 5 gamma per vector field component. The principal elements that assure this performance level are very low power dissipation triaxial feedback coils surrounding ring core flux-gates and temperature control of the critical components of two-loop feedback electronics. An analysis of the calibration problem points to the need for improved test facilities.

  5. A non-uniform three-gap buncher cavity with suppression of transverse-electromagnetic mode leakage in the triaxial klystron amplifier

    SciTech Connect

    Qi, Zumin; Zhang, Jun Zhong, Huihuang; Zhu, Danni; Qiu, Yongfeng

    2014-01-15

    The triaxial klystron amplifier is an efficient high power relativistic klystron amplifier operating at high frequencies due to its coaxial structure with large radius. However, the coaxial structures result in coupling problems among the cavities as the TEM mode is not cut-off in the coaxial tube. Therefore, the suppression of the TEM mode leakage, especially the leakage from the buncher cavity to the input cavity, is crucial in the design of a triaxial klystron amplifier. In this paper, a non-uniform three-gap buncher cavity is proposed to suppress the TEM mode leakage. The cold cavity analysis shows that the non-uniform three-gap buncher cavity can significantly suppress the TEM mode generation compared to a uniform three-gap buncher cavity. Particle-in-cell simulation shows that the power leakage to the input cavity is less than 1.5‰ of the negative power in the buncher cavity and the buncher cavity can efficiently modulate an intense relativistic electron beam free of self-oscillations. A fundamental current modulation depth of 117% is achieved by employing the proposed non-uniform buncher cavity into an X-band triaxial amplifier, which results in the high efficiency generation of high power microwave.

  6. A non-uniform three-gap buncher cavity with suppression of transverse-electromagnetic mode leakage in the triaxial klystron amplifier

    NASA Astrophysics Data System (ADS)

    Qi, Zumin; Zhang, Jun; Zhong, Huihuang; Zhu, Danni; Qiu, Yongfeng

    2014-01-01

    The triaxial klystron amplifier is an efficient high power relativistic klystron amplifier operating at high frequencies due to its coaxial structure with large radius. However, the coaxial structures result in coupling problems among the cavities as the TEM mode is not cut-off in the coaxial tube. Therefore, the suppression of the TEM mode leakage, especially the leakage from the buncher cavity to the input cavity, is crucial in the design of a triaxial klystron amplifier. In this paper, a non-uniform three-gap buncher cavity is proposed to suppress the TEM mode leakage. The cold cavity analysis shows that the non-uniform three-gap buncher cavity can significantly suppress the TEM mode generation compared to a uniform three-gap buncher cavity. Particle-in-cell simulation shows that the power leakage to the input cavity is less than 1.5‰ of the negative power in the buncher cavity and the buncher cavity can efficiently modulate an intense relativistic electron beam free of self-oscillations. A fundamental current modulation depth of 117% is achieved by employing the proposed non-uniform buncher cavity into an X-band triaxial amplifier, which results in the high efficiency generation of high power microwave.

  7. Evaluation of SD-208, a TGF-β-RI Kinase Inhibitor, as an Anticancer Agent in Retinoblastoma.

    PubMed

    Fadakar, Puran; Akbari, Abolfazl; Ghassemi, Fariba; Mobini, Gholam Reza; Mohebi, Masoumeh; Bolhassani, Manzar; Abed Khojasteh, Hoda; Heidari, Mansour

    2016-06-01

    Retinoblastoma is the most common intraocular tumor in children resulting from genetic alterations and transformation of mature retinal cells. The objective of this study was to investigate the effects of SD-208, TGF-β-RI kinase inhibitor, on the expression of some miRNAs including a miR-17/92 cluster in retinoblastoma cells. Prior to initiate this work, the cell proliferation was studied by Methyl Thiazolyl Tetrazolium (MTT) and bromo-2'-deoxyuridine (BrdU) assays. Then, the expression patterns of four miRNAs (18a, 20a, 22, and 34a) were investigated in the treated SD-208 (0.0, 1, 2 and 3 µM) and untreated Y-79 cells. A remarkable inhibition of the cell proliferation was found in Y-79 cells treated with SD-208 versus untreated cells. Also, the expression changes were observed in miRNAs 18a, 20a, 22 and 34a in response to SD-208 treatment (P<0.05). The findings of the present study suggest that the anti-cancer effect of SD-208 may be exerted due to the regulation of specific miRNAs, at least in this particular retinoblastoma cell line. To the best of the researchers' knowledge, this is the first report demonstrating that the SD-208 could alter the expression of tumor suppressive miRNAs as well as oncomiRs in vitro. In conclusion, the present data suggest that SD-208 could be an alternative agent in retinoblastoma treatment. PMID:27306340

  8. Order-Order Transition of C → sdG → sL → S in ABC Triblock Copolymer Thin Film Induced by Solvent Vapor.

    PubMed

    Luo, Chunxia; Huang, Weihuan; Han, Yanchun

    2009-04-01

    The morphology transition of polystyrene-block-poly(butadiene)-block-poly(2-vinylpyridine) (SBV) triblock thin film induced in benzene vapor showing weak selectivity for PS is investigated. The order-order transitions (OOT) in the sequence of core-shell cylinders (C), sphere in 'diblock gyroid' (sdG), sphere in lamella (sL) and sphere (S) are observed. The projection along (111) direction in Gyroid phase (sdG(111)) is found to epitaxially grow from C(001) in the film. Instead of sdG(111), sdG(110)(0.1875) develops to the phase of sL. Consequently, the film experiences the transition sequence of sdG(111) → sdG(211) → sdG(110)(0.25)  → sdG(110)(0.1875) between C and sL. The mechanism is analyzed from the total surface area of the blocks.

  9. Experimental evaluation of a constitutive model for inelastic flow and damage evolution in solids subjected to triaxial compression

    SciTech Connect

    Fossum, A.F.; Brodsky, N.S.; Munson, D.E.

    1992-12-31

    Recent concern over the potential for creep induced development of a damaged rock zone adjacent to shafts and rooms at the Waste Isolation Pilot Plant (WIPP) has motivated the formulation of a coupled constitutive description of continuum salt creep and damage. This constitutive model gives time-dependent inelastic flow and pressure-sensitive damage in crystalline solids. Initially the constitutive model was successfully used to simulate multiaxial, i.e. true triaxial, experiments obtained at relatively high, 2.5 to 20 MPa, confining pressures. Predictions of the complete creep curve, including the heretofore unmodeled tertiary creep, were also demonstrated. However, comparisons of model predictions with data were hampered because the bulk of the creep data existing on WIPP salt was intentionally obtained under confining pressures typically greater than 15 MPa, in an attempt to match the underground in situ lithostatic pressure level. It was realized that the high confining pressures suppressed tertiary creep and resulted in better defined steady state creep responses. To address the tertiary creep process directly, a number of creep tests were conducted at lower confining pressures for the explicit purpose of creating dilatant behavior.

  10. Experimental evaluation of a constitutive model for inelastic flow and damage evolution in solids subjected to triaxial compression

    SciTech Connect

    Fossum, A.F.; Brodsky, N.S. ); Chan, K.S. ); Munson, D.E. )

    1992-01-01

    Recent concern over the potential for creep induced development of a damaged rock zone adjacent to shafts and rooms at the Waste Isolation Pilot Plant (WIPP) has motivated the formulation of a coupled constitutive description of continuum salt creep and damage. This constitutive model gives time-dependent inelastic flow and pressure-sensitive damage in crystalline solids. Initially the constitutive model was successfully used to simulate multiaxial, i.e. true triaxial, experiments obtained at relatively high, 2.5 to 20 MPa, confining pressures. Predictions of the complete creep curve, including the heretofore unmodeled tertiary creep, were also demonstrated. However, comparisons of model predictions with data were hampered because the bulk of the creep data existing on WIPP salt was intentionally obtained under confining pressures typically greater than 15 MPa, in an attempt to match the underground in situ lithostatic pressure level. It was realized that the high confining pressures suppressed tertiary creep and resulted in better defined steady state creep responses. To address the tertiary creep process directly, a number of creep tests were conducted at lower confining pressures for the explicit purpose of creating dilatant behavior.

  11. Gait Analysis of Conventional Total Knee Arthroplasty and Bicruciate Stabilized Total Knee Arthroplasty Using a Triaxial Accelerometer.

    PubMed

    Tomite, Takenori; Saito, Hidetomo; Aizawa, Toshiaki; Kijima, Hiroaki; Miyakoshi, Naohisa; Shimada, Yoichi

    2016-01-01

    One component of conventional total knee arthroplasty is removal of the anterior cruciate ligament, and the knee after total knee arthroplasty has been said to be a knee with anterior cruciate ligament dysfunction. Bicruciate stabilized total knee arthroplasty is believed to reproduce anterior cruciate ligament function in the implant and provide anterior stability. Conventional total knee arthroplasty was performed on the right knee and bicruciate stabilized total knee arthroplasty was performed on the left knee in the same patient, and a triaxial accelerometer was fitted to both knees after surgery. Gait analysis was then performed and is reported here. The subject was a 78-year-old woman who underwent conventional total knee arthroplasty on her right knee and bicruciate stabilized total knee arthroplasty on her left knee. On the femoral side with bicruciate stabilized total knee arthroplasty, compared to conventional total knee arthroplasty, there was little acceleration in the x-axis direction (anteroposterior direction) in the early swing phase. Bicruciate stabilized total knee arthroplasty may be able to replace anterior cruciate ligament function due to the structure of the implant and proper anteroposterior positioning. PMID:27648328

  12. A microcomputer-based data acquisition and control system for the direct shear, ring shear, triaxial shear, and consolidation tests

    USGS Publications Warehouse

    Powers, Philip S.

    1983-01-01

    This report is intended to provide internal documentation for the U.S. Geological Survey laboratory's automatic data acquisition system. The operating procedures for each type of test are designed to independently lead a first-time user through the various stages of using the computer to control the test. Continuing advances in computer technology and the availability of desktop microcomputers with a wide variety of peripheral equipment at a reasonable cost can create an efficient automated geotechnical testing environment. A geotechnical testing environment is shown in figure 1. Using an automatic data acquisition system, laboratory test data from a variety of sensors can be collected, and manually or automatically recorded on a magnetic device at the same apparent time. The responses of a test can be displayed graphically on a CRT in a matter of seconds, giving the investigator an opportunity to evaluate the test data, and to make timely, informed decisions on such matters as whether to continue testing, abandon a test, or modify procedures. Data can be retrieved and results reported in tabular form, or graphic plots, suitable for publication. Thermistors, thermocouples, load cells, pressure transducers, and linear variable differential transformers are typical sensors which are incorporated in automated systems. The geotechnical tests which are most practical to automate are the long-term tests which often require readings to be recorded outside normal work hours and on weekends. Automation applications include incremental load consolidation tests, constant-rate-of-strain consolidation tests, direct shear tests, ring shear tests, and triaxial shear tests.

  13. A triaxial accelerometer-based physical-activity recognition via augmented-signal features and a hierarchical recognizer.

    PubMed

    Khan, Adil Mehmood; Lee, Young-Koo; Lee, Sungyoung Y; Kim, Tae-Seong

    2010-09-01

    Physical-activity recognition via wearable sensors can provide valuable information regarding an individual's degree of functional ability and lifestyle. In this paper, we present an accelerometer sensor-based approach for human-activity recognition. Our proposed recognition method uses a hierarchical scheme. At the lower level, the state to which an activity belongs, i.e., static, transition, or dynamic, is recognized by means of statistical signal features and artificial-neural nets (ANNs). The upper level recognition uses the autoregressive (AR) modeling of the acceleration signals, thus, incorporating the derived AR-coefficients along with the signal-magnitude area and tilt angle to form an augmented-feature vector. The resulting feature vector is further processed by the linear-discriminant analysis and ANNs to recognize a particular human activity. Our proposed activity-recognition method recognizes three states and 15 activities with an average accuracy of 97.9% using only a single triaxial accelerometer attached to the subject's chest.

  14. Unified framework for triaxial accelerometer-based fall event detection and classification using cumulants and hierarchical decision tree classifier

    PubMed Central

    Kambhampati, Satya Samyukta; Singh, Vishal; Ramkumar, Barathram

    2015-01-01

    In this Letter, the authors present a unified framework for fall event detection and classification using the cumulants extracted from the acceleration (ACC) signals acquired using a single waist-mounted triaxial accelerometer. The main objective of this Letter is to find suitable representative cumulants and classifiers in effectively detecting and classifying different types of fall and non-fall events. It was discovered that the first level of the proposed hierarchical decision tree algorithm implements fall detection using fifth-order cumulants and support vector machine (SVM) classifier. In the second level, the fall event classification algorithm uses the fifth-order cumulants and SVM. Finally, human activity classification is performed using the second-order cumulants and SVM. The detection and classification results are compared with those of the decision tree, naive Bayes, multilayer perceptron and SVM classifiers with different types of time-domain features including the second-, third-, fourth- and fifth-order cumulants and the signal magnitude vector and signal magnitude area. The experimental results demonstrate that the second- and fifth-order cumulant features and SVM classifier can achieve optimal detection and classification rates of above 95%, as well as the lowest false alarm rate of 1.03%. PMID:26609414

  15. Gait Analysis of Conventional Total Knee Arthroplasty and Bicruciate Stabilized Total Knee Arthroplasty Using a Triaxial Accelerometer

    PubMed Central

    Saito, Hidetomo; Aizawa, Toshiaki; Miyakoshi, Naohisa; Shimada, Yoichi

    2016-01-01

    One component of conventional total knee arthroplasty is removal of the anterior cruciate ligament, and the knee after total knee arthroplasty has been said to be a knee with anterior cruciate ligament dysfunction. Bicruciate stabilized total knee arthroplasty is believed to reproduce anterior cruciate ligament function in the implant and provide anterior stability. Conventional total knee arthroplasty was performed on the right knee and bicruciate stabilized total knee arthroplasty was performed on the left knee in the same patient, and a triaxial accelerometer was fitted to both knees after surgery. Gait analysis was then performed and is reported here. The subject was a 78-year-old woman who underwent conventional total knee arthroplasty on her right knee and bicruciate stabilized total knee arthroplasty on her left knee. On the femoral side with bicruciate stabilized total knee arthroplasty, compared to conventional total knee arthroplasty, there was little acceleration in the x-axis direction (anteroposterior direction) in the early swing phase. Bicruciate stabilized total knee arthroplasty may be able to replace anterior cruciate ligament function due to the structure of the implant and proper anteroposterior positioning. PMID:27648328

  16. Inversion of sparse photometric data of asteroids using triaxial ellipsoid shape models and a Lommel-Seeliger scattering law

    NASA Astrophysics Data System (ADS)

    Cellino, A.; Muinonen, K.; Hestroffer, D.; Carbognani, A.

    2015-12-01

    The inversion of sparse photometric data of asteroids to derive from them information about the spin and shape properties of the objects is a hot topic in the era of the Gaia space mission. We have used a rigorous analytical treatment of the Lommel-Seeliger light-scattering law computed for the particular case of bodies having the shapes of ideal triaxial ellipsoids, and we have implemented this in the software developed for the treatment of Gaia photometric data for asteroids. In a set of numerical simulations, the performances of the photometry inversion code improve significantly with respect to the case in which purely geometric scattering is taken into account. When applied to real photometric data of asteroids obtained in the past by the Hipparcos satellite, however, we do not see any relevant improvement of the performances, due to the poor accuracy of these measurements. These results suggest that the role played by the light-scattering properties of asteroid surfaces is indeed relevant. On the other hand, any refined treatment of light-scattering effects cannot improve the reliability of photometric inversion when the quantity and quality of available data are much worse than what we expect to obtain from Gaia.

  17. Numerical Analysis of Free-Edge Effect on Size-Influenced Mechanical Properties of Single-Layer Triaxially Braided Composites

    NASA Astrophysics Data System (ADS)

    Zhang, Chao; Binienda, Wieslaw K.

    2014-12-01

    The mechanical properties of triaxially braided composites under transverse loads are found to be size-dependent, due to the presence of free-edge effect. Numerical studies of the mechanical behaviors of straight-sided coupon specimens and an infinitely large plate under both axial and transverse tension loads were conducted using a meso-scale finite element model. The numerical model correlates well with experimental results, successfully capturing the free-edge warping phenomena under transverse tension. Free-edge effect is observed as out-of-plane warping, and it can be correlated to the premature damage initiation in the affected area. The numerical results characterize the impact of free-edge effects on the global stress-strain response and local failure mechanisms. By conducting dimensional analysis, the relationships of effective stiffness and strength against specimen width are quantified using Weibull equations. The results of this study indicate that the free-edge effect is an inherent behavior of braided architecture. The free-edge effect produces significantly reduced transverse tension modulus and strength measurements.

  18. Understanding differences between healthy swallows and penetration-aspiration swallows via compressive sensing of tri-axial swallowing accelerometry signals

    NASA Astrophysics Data System (ADS)

    Sejdić, Ervin; Dudik, Joshua M.; Kurosu, Atsuko; Jestrović, Iva; Coyle, James L.

    2014-05-01

    Swallowing accelerometry is a promising tool for non-invasive assessment of swallowing difficulties. A recent contribution showed that swallowing accelerometry signals for healthy swallows and swallows indicating laryn- geal penetration or tracheal aspiration have different time-frequency structures, which may be problematic for compressive sensing schemes based on time-frequency dictionaries. In this paper, we examined the effects of dif- ferent swallows on the accuracy of a compressive sensing scheme based on modulated discrete prolate spheroidal sequences. We utilized tri-axial swallowing accelerometry signals recorded from four patients during routinely schedule videofluoroscopy exams. In particular, we considered 77 swallows approximately equally distributed between healthy swallows and swallows presenting with some penetration/aspiration. Our results indicated that the swallow type does not affect the accuracy of a considered compressive sensing scheme. Also, the results con- firmed previous findings that each individual axis contributes different information. Our findings are important for further developments of a device which is to be used for long-term monitoring of swallowing difficulties.

  19. Modelos autoconsistentes de sistemas estelares cuspidales y triaxiales con distribución de velocidades casi isotrópica

    NASA Astrophysics Data System (ADS)

    Carpintero, D. D.; Muzzio, J. C.; Navone, H. D.; Zorzi, A. F.

    It has been shown in many works that it is possible to build stable, self-consistent models of triaxial stellar systems, even with cusps, and containing high percentages of chaotic orbits. Since all these models have been obtained from cold collapses, their velocity distributions are strongly radial. Also, chaos was computed using either Lyapunov exponents or SALI. However, models obtained by adiabatic deformation of spherical systems, in which the velocity distribution is more isotropic, showed a very low level of chaos, though it must be noted that the method of detecting chaos used in this case, namely the variation of orbital frequencies, is less sensitive than the abovementioned methods. In this work, we present models obtained by adiabatic deformation, in which we compute the fraction of chaotic orbits using both Lyapunov exponents and variation of orbital frequencies. Our results show that the percentages of chaotic orbits is significant, though they are smaller than those obtained in models with strong radial velocity components. FULL TEXT IN SPANISH

  20. Validity of using tri-axial accelerometers to measure human movement - Part I: Posture and movement detection.

    PubMed

    Lugade, Vipul; Fortune, Emma; Morrow, Melissa; Kaufman, Kenton

    2014-02-01

    A robust method for identifying movement in the free-living environment is needed to objectively measure physical activity. The purpose of this study was to validate the identification of postural orientation and movement from acceleration data against visual inspection from video recordings. Using tri-axial accelerometers placed on the waist and thigh, static orientations of standing, sitting, and lying down, as well as dynamic movements of walking, jogging and transitions between postures were identified. Additionally, subjects walked and jogged at self-selected slow, comfortable, and fast speeds. Identification of tasks was performed using a combination of the signal magnitude area, continuous wavelet transforms and accelerometer orientations. Twelve healthy adults were studied in the laboratory, with two investigators identifying tasks during each second of video observation. The intraclass correlation coefficients for inter-rater reliability were greater than 0.95 for all activities except for transitions. Results demonstrated high validity, with sensitivity and positive predictive values of greater than 85% for sitting and lying, with walking and jogging identified at greater than 90%. The greatest disagreement in identification accuracy between the algorithm and video occurred when subjects were asked to fidget while standing or sitting. During variable speed tasks, gait was correctly identified for speeds between 0.1m/s and 4.8m/s. This study included a range of walking speeds and natural movements such as fidgeting during static postures, demonstrating that accelerometer data can be used to identify orientation and movement among the general population.

  1. Experimental Techniques for Evaluating the Effects of Aging on Impact and High Strain Rate Properties of Triaxial Braided Composite Materials

    NASA Technical Reports Server (NTRS)

    Pereira, J. Michael; Roberts, Gary D.; Ruggeri, Charles R.; Gilat, Amos; Matrka, Thomas

    2010-01-01

    An experimental program is underway to measure the impact and high strain rate properties of triaxial braided composite materials and to quantify any degradation in properties as a result of thermal and hygroscopic aging typically encountered during service. Impact tests are being conducted on flat panels using a projectile designed to induce high rate deformation similar to that experienced in a jet engine fan case during a fan blade-out event. The tests are being conducted on as-fabricated panels and panels subjected to various numbers of aging cycles. High strain rate properties are being measured using a unique Hopkinson bar apparatus that has a larger diameter than conventional Hopkinson bars. This larger diameter is needed to measure representative material properties because of the large unit cell size of the materials examined in this work. In this paper the experimental techniques used for impact and high strain rate testing are described and some preliminary results are presented for both as-fabricated and aged composites.

  2. Gait Analysis of Conventional Total Knee Arthroplasty and Bicruciate Stabilized Total Knee Arthroplasty Using a Triaxial Accelerometer

    PubMed Central

    Saito, Hidetomo; Aizawa, Toshiaki; Miyakoshi, Naohisa; Shimada, Yoichi

    2016-01-01

    One component of conventional total knee arthroplasty is removal of the anterior cruciate ligament, and the knee after total knee arthroplasty has been said to be a knee with anterior cruciate ligament dysfunction. Bicruciate stabilized total knee arthroplasty is believed to reproduce anterior cruciate ligament function in the implant and provide anterior stability. Conventional total knee arthroplasty was performed on the right knee and bicruciate stabilized total knee arthroplasty was performed on the left knee in the same patient, and a triaxial accelerometer was fitted to both knees after surgery. Gait analysis was then performed and is reported here. The subject was a 78-year-old woman who underwent conventional total knee arthroplasty on her right knee and bicruciate stabilized total knee arthroplasty on her left knee. On the femoral side with bicruciate stabilized total knee arthroplasty, compared to conventional total knee arthroplasty, there was little acceleration in the x-axis direction (anteroposterior direction) in the early swing phase. Bicruciate stabilized total knee arthroplasty may be able to replace anterior cruciate ligament function due to the structure of the implant and proper anteroposterior positioning.

  3. Classification accuracy of a single tri-axial accelerometer for training background and experience level in runners.

    PubMed

    Kobsar, Dylan; Osis, Sean T; Hettinga, Blayne A; Ferber, Reed

    2014-07-18

    Accelerometers are increasingly used tools for gait analysis, but there remains a lack of research on their application to running and their ability to classify running patterns. The purpose of this study was to conduct an exploratory examination into the capability of a tri-axial accelerometer to classify runners of different training backgrounds and experience levels, according to their 3-dimensional (3D) accelerometer data patterns. Training background was examined with 14 competitive soccer players and 12 experienced marathon runners, and experience level was examined with 16 first-time and the same 12 experienced marathon runners. Discrete variables were extracted from 3D accelerations during a short run using root mean square, wavelet transformation, and autocorrelation procedures. A principal component analysis (PCA) was conducted on all variables, including gait speed to account for covariance. Eight PCs were retained, explaining 88% of the variance in the data. A stepwise discriminant analysis of PCs was used to determine the binary classification accuracy for training background and experience level, with and without the PC of Speed. With Speed, the accelerometer correctly classified 96% of runners for both training background and experience level. Without Speed, the accelerometer correctly classified 85% of runners based on training background, but only 68% based on experience level. These findings suggest that the accelerometer is effective in classifying athletes of different training backgrounds, but is less effective for classifying runners of different experience levels where gait speed is the primary discriminator. PMID:24837221

  4. Understanding differences between healthy swallows and penetration-aspiration swallows via compressive sensing of tri-axial swallowing accelerometry signals.

    PubMed

    Sejdić, Ervin; Dudik, Joshua M; Kurosu, Atsuko; Jestrović, Iva; Coyle, James L

    2014-05-23

    Swallowing accelerometry is a promising tool for non-invasive assessment of swallowing difficulties. A recent contribution showed that swallowing accelerometry signals for healthy swallows and swallows indicating laryngeal penetration or tracheal aspiration have different time-frequency structures, which may be problematic for compressive sensing schemes based on time-frequency dictionaries. In this paper, we examined the effects of different swallows on the accuracy of a compressive sensing scheme based on modulated discrete prolate spheroidal sequences. We utilized tri-axial swallowing accelerometry signals recorded from four patients during routinely schedule videofluoroscopy exams. In particular, we considered 77 swallows approximately equally distributed between healthy swallows and swallows presenting with some penetration/aspiration. Our results indicated that the swallow type does not affect the accuracy of a considered compressive sensing scheme. Also, the results confirmed previous findings that each individual axis contributes different information. Our findings are important for further developments of a device which is to be used for long-term monitoring of swallowing difficulties.

  5. Understanding differences between healthy swallows and penetration-aspiration swallows via compressive sensing of tri-axial swallowing accelerometry signals

    PubMed Central

    Sejdić, Ervin; Dudik, Joshua M.; Kurosu, Atsuko; Jestrović, Iva; Coyle, James L.

    2014-01-01

    Swallowing accelerometry is a promising tool for non-invasive assessment of swallowing difficulties. A recent contribution showed that swallowing accelerometry signals for healthy swallows and swallows indicating laryngeal penetration or tracheal aspiration have different time-frequency structures, which may be problematic for compressive sensing schemes based on time-frequency dictionaries. In this paper, we examined the effects of different swallows on the accuracy of a compressive sensing scheme based on modulated discrete prolate spheroidal sequences. We utilized tri-axial swallowing accelerometry signals recorded from four patients during routinely schedule videofluoroscopy exams. In particular, we considered 77 swallows approximately equally distributed between healthy swallows and swallows presenting with some penetration/aspiration. Our results indicated that the swallow type does not affect the accuracy of a considered compressive sensing scheme. Also, the results confirmed previous findings that each individual axis contributes different information. Our findings are important for further developments of a device which is to be used for long-term monitoring of swallowing difficulties. PMID:25332758

  6. Refractive Error and Ocular Parameters: Comparison of Two SD-OCT Systems

    PubMed Central

    Ostrin, Lisa A.; Yuzuriha, Jill; Wildsoet, Christine F.

    2015-01-01

    Purpose Spectral domain optical coherence tomography (SD-OCT) was used to examine the influence of refractive error (RE) on foveal retinal and choroidal thicknesses and scleral canal width (SCW). The performance of the Cirrus and Bioptigen SD-OCT instruments was compared in the same eyes. Methods Both eyes of forty healthy human subjects, ages 22 to 38 years, were dilated and imaged, with the Cirrus OCT, using 6 mm 5-line rasters collapsed into one line, one centered on the fovea and one bisecting the optic nerve head. Seventy-two of the same eyes were imaged with the Bioptigen OCT, using 6 mm × 6 mm scans, one centered on the fovea and one on the optic nerve head. Subfoveal retinal and choroidal thicknesses and SCW were measured. Axial lengths (AL) and REs were obtained using an IOLMaster and a Grand Seiko autorefractor, respectively. Results Only right eyes were included in analyses. Spherical equivalent REs ranged from −12.18 to +8.12 D (mean: −3.44 ± 4.06 D), and ALs ranged from 20.56 to 29.17 mm (mean: 24.86 ± 1.91 mm). Myopia was associated with relatively thin choroids at the fovea (p<0.05) but normal retinal thickness. SCW was significantly correlated with AL as measured with the Bioptigen OCT (p<0.05). Retinal and choroidal thicknesses recorded with the Bioptigen OCT tended to be smaller than values obtained with the Cirrus OCT (mean difference: 5.63 and 24.76 µm, respectively), while the converse was true for the SCW (mean difference: 25.45 µm). Conclusions The finding that high myopes tend to have a thinner subfoveal choroid is consistent with previous studies. That high myopia was linked to enlarged scleral canals may help to explain the increased risk of glaucoma in myopia. Observed differences obtained with the Cirrus and Bioptigen instruments urge caution in comparing results collected with different instruments. PMID:25785537

  7. Macular SD-OCT Outcome Measures: Comparison of Local Structure-Function Relationships and Dynamic Range

    PubMed Central

    Miraftabi, Arezoo; Amini, Navid; Morales, Esteban; Henry, Sharon; Yu, Fei; Afifi, Abdolmonem; Coleman, Anne L.; Caprioli, Joseph; Nouri-Mahdavi, Kouros

    2016-01-01

    Purpose We tested the hypothesis that the macular ganglion cell layer (GCL) thickness demonstrates a stronger structure-function (SF) relationship and extends the useful range of macular measurements compared with combined macular inner layer or full thickness. Methods Ninety-eight glaucomatous eyes and eight normal eyes with macular spectral domain optical coherence tomography (SD-OCT) volume scans and 10-2 visual fields were enrolled. Inner plexiform layer (IPL), GCL, macular retinal nerve fiber layer (mRNFL), ganglion cell-inner plexiform layer (GCIPL), ganglion cell complex (GCC), and full thickness (FT) measurements were calculated for 8 × 8 arrays of 3° superpixels. Main outcome measures were local structure-function relationships between macular superpixels and corresponding sensitivities on 10-2 fields after adjusting for ganglion cell displacement, dynamic range of measurements, and the change point (total deviation value where macular parameters reached measurement floor). Results Median (interquartile range [IQR]) mean deviation was −7.2 (−11.6 to −3.2) dB in glaucoma eyes. Strength of SF relationships was highest for GCIPL, GCL, GCC, and IPL (ρ = 0.635, 0.627, 0.621, and 0.577, respectively; P ≤ 0.046 for comparisons against GCIPL). Highest SF correlations coincided with the peak of GCL thickness, where the dynamic range was widest for FT (81.1 μm), followed by GCC (65.7 μm), GCIPL (54.9 μm), GCL (35.2 μm), mRNFL (27.5 μm), and IPL (20.9 μm). Change points were similar for all macular parameters (−7.8 to −8.9 dB). Conclusions GCIPL, GCL, and GCC demonstrated comparable SF relationships while FT, GCC, and GCIPL had the widest dynamic range. Measurement of GCL did not extend the range of useful structural measurements. Measuring GCL does not provide any advantage for detection of progression with current SD-OCT technology. PMID:27623336

  8. Leveraging master-slave OpenFlow controller arrangement to improve control plane resiliency in SD-EONs.

    PubMed

    Chen, Xiaoliang; Zhao, Bin; Ma, Shoujiang; Chen, Cen; Hu, Daoyun; Zhou, Wenshuang; Zhu, Zuqing

    2015-03-23

    In this paper, we study how to improve the control plane resiliency of software-defined elastic optical networks (SD-EONs) and design a master-slave OpenFlow (OF) controller arrangement. Specifically, we introduce two OF controllers (OF-Cs), i.e., the master and slave OF-Cs, and make them work in a collaborative way to protect the SD-EON against controller failures. We develop a controller communication protocol (CCP) to facilitate the cooperation of the two OF-Cs. With the CCP, the master OF-C (M-OF-C) can synchronize network status to the slave OF-C (S-OF-C) in real time, while S-OF-C can quickly detect the failure of M-OF-C and take over the network control and management (NC&M) tasks timely to avoid service disruption. We implement the proposed framework in an SD-EON control plane testbed built with high-performance servers, and perform NC&M experiments with different network failure scenarios to demonstrate its effectiveness. Experimental results indicate that the proposed system can restore services in both the data and control planes of SD-EON jointly while maintaining relatively good scalability. To the best of our knowledge, this is the first demonstration that realizes control plane resiliency in SD-EONs.

  9. Spectrum of {gamma} rays from the decay of SD to normal states in {sup 191}Hg

    SciTech Connect

    Gassmann, D.; Khoo, T.L.; Lauritsen, T.

    1995-08-01

    In B.a.7. we propose that the statistical spectrum emitted from a sharp single excited state serves as a probe of pairing in excited states. A specific test of this proposal is the comparison of the spectra from even-even and odd-even nuclei. Whereas a pair gap exists in an even-even nucleus, it gets filled in an odd-even nucleus. Consequently, low-energy transitions can arise in the latter case, whereas they are calculated to be absent in the former case because very few levels exist in the cold gap region. In addition, transitions between 1.4 - 2.2 MeV, which {open_quotes}jump{close_quotes} across the gap, are predicted to have lower yield in the odd-even nuclei. Serendipitously, decay from a superdeformed state serves as a good initial excited sharp state. We extracted the spectrum pairwise-coincident with SD lines in {sup 191}Hg from Gammasphere data and compared it with the equivalent spectra from the even-even nuclei {sup 192,194}Hg. The differences that are predicted to occur are indeed observed. Thus, the data support our proposal that the reduction of pairing with thermal excitation energy can be probed with statistical decay spectra.

  10. Neutron Skins and Halo Orbits in the sd and pf Shells.

    PubMed

    Bonnard, J; Lenzi, S M; Zuker, A P

    2016-05-27

    The strong dependence of Coulomb energies on nuclear radii makes it possible to extract the latter from calculations of the former. The resulting estimates of neutron skins indicate that two mechanisms are involved. The first one-isovector monopole polarizability-amounts to noting that when a particle is added to a system it drives the radii of neutrons and protons in different directions, tending to equalize the radii of both fluids independently of the neutron excess. This mechanism is well understood and the Duflo-Zuker (small) neutron skin values derived 14 years ago are consistent with recent measures and estimates. The alternative mechanism involves halo orbits whose huge sizes tend to make the neutron skins larger and have a subtle influence on the radial behavior of sd and pf shell nuclei. In particular, they account for the sudden rise in the isotope shifts of nuclei beyond N=28 and the near constancy of radii in the A=40-56 region. This mechanism, detected here for the first time, is not well understood and may well go beyond the Efimov physics usually associated with halo orbits.

  11. Can chest trauma patients provide breath sample with Lion SD-400 Alcometer?

    PubMed

    Rathinam, Sridhar; Luke, David; Nanjaiah, Prakash; Kalkat, Maninder S; Steyn, Richard S

    2009-06-01

    Various investigators have addressed the minimum lung function required to activate breathalyzers, and the impact of comorbid respiratory illness. We postulated that subjects with significant chest trauma may have difficulty in providing an adequate breathalyzer sample. A prospective self-controlled study of 20 patients who underwent thoracotomy was conducted between August 2005 and December 2005, using a Lion Alcometer SD-400. The mean age of the patients was 69.3 years (range, 37-83 years). Preoperatively, their mean forced expiratory volume was 1.97 L (range, 1.19-2.46 L), and peak expiratory flow rate was 240 L min(-1) (range, 126-520 L min(-1)). Postoperatively, mean forced expiratory volume was 1.14 L (range, 0.34-2.2 L) and peak expiratory flow rate was 179 L min(-1) (range, 36-492 L min(-1)). These decreases were highly significant. All patients activated the breathalyzer device preoperatively, but only 2 (10%) could activate it postoperatively. Extrapolating this to patients with chest injury, most may find it impossible to activate breathalyzers. PMID:19643853

  12. Risk and Vulnerability Analysis of Satellites Due to MM/SD with PIRAT

    NASA Astrophysics Data System (ADS)

    Kempf, Scott; Schafer, Frank Rudolph, Martin; Welty, Nathan; Donath, Therese; Destefanis, Roberto; Grassi, Lilith; Janovsky, Rolf; Evans, Leanne; Winterboer, Arne

    2013-08-01

    Until recently, the state-of-the-art assessment of the threat posed to spacecraft by micrometeoroids and space debris was limited to the application of ballistic limit equations to the outer hull of a spacecraft. The probability of no penetration (PNP) is acceptable for assessing the risk and vulnerability of manned space mission, however, for unmanned missions, whereby penetrations of the spacecraft exterior do not necessarily constitute satellite or mission failure, these values are overly conservative. The newly developed software tool PIRAT (Particle Impact Risk and Vulnerability Analysis Tool) has been developed based on the Schäfer-Ryan-Lambert (SRL) triple-wall ballistic limit equation (BLE), applicable for various satellite components. As a result, it has become possible to assess the individual failure rates of satellite components. This paper demonstrates the modeling of an example satellite, the performance of a PIRAT analysis and the potential for subsequent design optimizations with respect of micrometeoroid and space debris (MM/SD) impact risk.

  13. Effect and mechanism of Salicornia bigelovii Torr. plant salt on blood pressure in SD rats.

    PubMed

    Zhang, Shumeng; Wei, Mingqian; Cao, Chunjie; Ju, Yaoyao; Deng, Yanqun; Ye, Tianwen; Xia, Zufeng; Chen, Meizhen

    2015-03-01

    In this paper, the effect and mechanism of Salicornia bigelovii Torr. plant salt (SPS) on blood pressure in Sprague Dawley (SD) rats were investigated. The results showed that the edible salt induced hypertension, but the SPS did not. Organ indices and Hematoxylin-Eosin (HE) staining analysis indicated that SPS had a protective effect on the kidney and liver. In comparison with the edible salt-treated group, nitric oxide (NO) content, angiotensin-II (Ang-II) and endothelin-1 (ET-1) levels in the serum of the SPS-treated group had no obvious changes, but serum creatinine concentration significantly decreased. Moreover, superoxide dismutase (SOD) and Na(+)-K(+)-ATPase activity increased while malondialdehyde (MDA) content decreased in the SPS-treated group. In conclusion, a long-term high salt intake could lead to hypertension. SPS, as a salt substitute, could increase the body's antioxidant ability to protect the kidney and liver from the damage caused by a high salt intake and effectively avoid the occurrence of hypertension. PMID:25631641

  14. Neutron Skins and Halo Orbits in the sd and pf Shells.

    PubMed

    Bonnard, J; Lenzi, S M; Zuker, A P

    2016-05-27

    The strong dependence of Coulomb energies on nuclear radii makes it possible to extract the latter from calculations of the former. The resulting estimates of neutron skins indicate that two mechanisms are involved. The first one-isovector monopole polarizability-amounts to noting that when a particle is added to a system it drives the radii of neutrons and protons in different directions, tending to equalize the radii of both fluids independently of the neutron excess. This mechanism is well understood and the Duflo-Zuker (small) neutron skin values derived 14 years ago are consistent with recent measures and estimates. The alternative mechanism involves halo orbits whose huge sizes tend to make the neutron skins larger and have a subtle influence on the radial behavior of sd and pf shell nuclei. In particular, they account for the sudden rise in the isotope shifts of nuclei beyond N=28 and the near constancy of radii in the A=40-56 region. This mechanism, detected here for the first time, is not well understood and may well go beyond the Efimov physics usually associated with halo orbits. PMID:27284653

  15. Alleviating anastrozole induced bone toxicity by selenium nanoparticles in SD rats.

    PubMed

    Vekariya, Kiritkumar K; Kaur, Jasmine; Tikoo, Kulbhushan

    2013-04-15

    Aromatase inhibitors like anastrozole play an undisputed key role in the treatment of breast cancer, but on the other hand, various side effects like osteoporosis and increased risk of bone fracture accompany the chronic administration of these drugs. Here we show for the first time that selenium nanoparticles, when given in conjugation to anastrozole, lower the bone toxicity caused by anastrozole and thus reduce the probable damage to the bone. Selenium nanoparticles at a dose of 5μg/ml significantly reduced the cell death caused by anastrozole (1μM) in HOS (human osteoblast) cells. In addition, our results also highlighted that in female SD rat model, SeNPs (0.25, 0.5, 1mg/kg/day) significantly prevented the decrease in bone density and increase in biochemical markers of bone resorption induced by anastrozole (0.2mg/kg/day) treatment. Histopathological examination of the femurs of SeNP treated group revealed ossification, mineralization, calcified cartilaginous deposits and a marginal osteoclastic activity, all of which indicate a marked restorative action, suggesting the protective action of the SeNPs. Interestingly, SeNPs (1mg/kg/day) also exhibited protective effect in ovariectomized rat model, by preventing osteoporosis, which signifies that bone loss due to estrogen deficiency can be effectively overcome by using SeNPs.

  16. Effect and mechanism of Salicornia bigelovii Torr. plant salt on blood pressure in SD rats.

    PubMed

    Zhang, Shumeng; Wei, Mingqian; Cao, Chunjie; Ju, Yaoyao; Deng, Yanqun; Ye, Tianwen; Xia, Zufeng; Chen, Meizhen

    2015-03-01

    In this paper, the effect and mechanism of Salicornia bigelovii Torr. plant salt (SPS) on blood pressure in Sprague Dawley (SD) rats were investigated. The results showed that the edible salt induced hypertension, but the SPS did not. Organ indices and Hematoxylin-Eosin (HE) staining analysis indicated that SPS had a protective effect on the kidney and liver. In comparison with the edible salt-treated group, nitric oxide (NO) content, angiotensin-II (Ang-II) and endothelin-1 (ET-1) levels in the serum of the SPS-treated group had no obvious changes, but serum creatinine concentration significantly decreased. Moreover, superoxide dismutase (SOD) and Na(+)-K(+)-ATPase activity increased while malondialdehyde (MDA) content decreased in the SPS-treated group. In conclusion, a long-term high salt intake could lead to hypertension. SPS, as a salt substitute, could increase the body's antioxidant ability to protect the kidney and liver from the damage caused by a high salt intake and effectively avoid the occurrence of hypertension.

  17. Classification of SD-OCT Volumes Using Local Binary Patterns: Experimental Validation for DME Detection.

    PubMed

    Lemaître, Guillaume; Rastgoo, Mojdeh; Massich, Joan; Cheung, Carol Y; Wong, Tien Y; Lamoureux, Ecosse; Milea, Dan; Mériaudeau, Fabrice; Sidibé, Désiré

    2016-01-01

    This paper addresses the problem of automatic classification of Spectral Domain OCT (SD-OCT) data for automatic identification of patients with DME versus normal subjects. Optical Coherence Tomography (OCT) has been a valuable diagnostic tool for DME, which is among the most common causes of irreversible vision loss in individuals with diabetes. Here, a classification framework with five distinctive steps is proposed and we present an extensive study of each step. Our method considers combination of various preprocessing steps in conjunction with Local Binary Patterns (LBP) features and different mapping strategies. Using linear and nonlinear classifiers, we tested the developed framework on a balanced cohort of 32 patients. Experimental results show that the proposed method outperforms the previous studies by achieving a Sensitivity (SE) and a Specificity (SP) of 81.2% and 93.7%, respectively. Our study concludes that the 3D features and high-level representation of 2D features using patches achieve the best results. However, the effects of preprocessing are inconsistent with different classifiers and feature configurations. PMID:27555965

  18. Optimization of a bioactive exopolysaccharide production from endophytic Fusarium solani SD5.

    PubMed

    Mahapatra, Subhadip; Banerjee, Debdulal

    2013-09-12

    Endophytic fungi were less investigated for exopolysaccharide production. In this study endophytic Fusarium solani SD5 was used for optimization of exopolysaccharide production. One variable at a time method and response surface methodology were employed to explore the optimum medium compositions and fermentation conditions. The organism produced maximum exopolysaccharide after 13.68 days of incubation at 28 °C in potato dextrose broth supplemented with (g%/l) glucose, 9.8; yeast extract, 0.69; KCl, 0.05; KH₂PO₄, 0.05 with medium pH 6.46. Use of 50 ml medium in 250 ml Erlenmeyer flask gives highest exopolysaccharide production. The organism produced more than two times higher exopolysaccharide (2.276 ± 0.032 g/l EPS) at optimized condition compared to pre-optimized condition (0.96 ± 0.021). In vivo toxicity test established nontoxic nature of the EPS (≤400 mg EPS/Kg of body weight). The EPS slightly altered intestinal indigenous bacteria and influenced the growth of beneficial Lactobacillus spp.

  19. Classification of SD-OCT Volumes Using Local Binary Patterns: Experimental Validation for DME Detection

    PubMed Central

    Cheung, Carol Y.; Wong, Tien Y.; Lamoureux, Ecosse; Milea, Dan; Mériaudeau, Fabrice; Sidibé, Désiré

    2016-01-01

    This paper addresses the problem of automatic classification of Spectral Domain OCT (SD-OCT) data for automatic identification of patients with DME versus normal subjects. Optical Coherence Tomography (OCT) has been a valuable diagnostic tool for DME, which is among the most common causes of irreversible vision loss in individuals with diabetes. Here, a classification framework with five distinctive steps is proposed and we present an extensive study of each step. Our method considers combination of various preprocessing steps in conjunction with Local Binary Patterns (LBP) features and different mapping strategies. Using linear and nonlinear classifiers, we tested the developed framework on a balanced cohort of 32 patients. Experimental results show that the proposed method outperforms the previous studies by achieving a Sensitivity (SE) and a Specificity (SP) of 81.2% and 93.7%, respectively. Our study concludes that the 3D features and high-level representation of 2D features using patches achieve the best results. However, the effects of preprocessing are inconsistent with different classifiers and feature configurations. PMID:27555965

  20. Classification of SD-OCT Volumes Using Local Binary Patterns: Experimental Validation for DME Detection.

    PubMed

    Lemaître, Guillaume; Rastgoo, Mojdeh; Massich, Joan; Cheung, Carol Y; Wong, Tien Y; Lamoureux, Ecosse; Milea, Dan; Mériaudeau, Fabrice; Sidibé, Désiré

    2016-01-01

    This paper addresses the problem of automatic classification of Spectral Domain OCT (SD-OCT) data for automatic identification of patients with DME versus normal subjects. Optical Coherence Tomography (OCT) has been a valuable diagnostic tool for DME, which is among the most common causes of irreversible vision loss in individuals with diabetes. Here, a classification framework with five distinctive steps is proposed and we present an extensive study of each step. Our method considers combination of various preprocessing steps in conjunction with Local Binary Patterns (LBP) features and different mapping strategies. Using linear and nonlinear classifiers, we tested the developed framework on a balanced cohort of 32 patients. Experimental results show that the proposed method outperforms the previous studies by achieving a Sensitivity (SE) and a Specificity (SP) of 81.2% and 93.7%, respectively. Our study concludes that the 3D features and high-level representation of 2D features using patches achieve the best results. However, the effects of preprocessing are inconsistent with different classifiers and feature configurations.

  1. Mercury(II) and methyl mercury speciation on Streptococcus pyogenes loaded Dowex Optipore SD-2.

    PubMed

    Tuzen, Mustafa; Uluozlu, Ozgur Dogan; Karaman, Isa; Soylak, Mustafa

    2009-09-30

    A solid phase extraction procedure based on speciation of mercury(II) and methyl mercury on Streptococcus pyogenes immobilized on Dowex Optipore SD-2 has been established. Selective and sequential elution with 0.1 mol L(-1) HCl for methyl mercury and 2 mol L(-1) HCl for mercury(II) were performed at pH 8. The determination of mercury levels was performed by cold vapour atomic absorption spectrometry (CVAAS). Optimal analytical conditions including pH, amounts of biosorbent, sample volumes, etc., were investigated. The influences of the some alkaline and earth alkaline ions and some transition metals on the recoveries were also investigated. The capacity of biosorbent for mercury(II) and methyl mercury was 4.8 and 3.4 mg g(-1). The detection limit (3 sigma) of the reagent blank for mercury(II) and methyl mercury was 2.1 and 1.5 ng L(-1). Preconcentration factor was calculated as 25. The relative standard deviations of the procedure were below 7%. The validation of the presented procedure is performed by the analysis of standard reference material (NRCC-DORM 2 Dogfish Muscle). The procedure was successfully applied to the speciation of mercury(II) and methyl mercury in natural water and environmental samples.

  2. Multiple Pregnancy

    MedlinePlus

    ... is called multiple pregnancy . If more than one egg is released during the menstrual cycle and each ... fraternal twins (or more). When a single fertilized egg splits, it results in multiple identical embryos. This ...

  3. Multiple myeloma

    MedlinePlus

    Plasma cell dyscrasia; Plasma cell myeloma; Malignant plasmacytoma; Plasmacytoma of bone; Myeloma - multiple ... Multiple myeloma most commonly causes: Low red blood cell count ( anemia ), which can lead to fatigue and ...

  4. Multiple Sclerosis

    MedlinePlus

    Multiple sclerosis (MS) is a nervous system disease that affects your brain and spinal cord. It damages the ... attacks healthy cells in your body by mistake. Multiple sclerosis affects women more than men. It often begins ...

  5. Finger Multiplication

    ERIC Educational Resources Information Center

    Simanihuruk, Mudin

    2011-01-01

    Multiplication facts are difficult to teach. Therefore many researchers have put a great deal of effort into finding multiplication strategies. Sherin and Fuson (2005) provided a good survey paper on the multiplication strategies research area. Kolpas (2002), Rendtorff (1908), Dabell (2001), Musser (1966) and Markarian (2009) proposed the finger…

  6. Multiple Sclerosis

    MedlinePlus

    ... Awards Enhancing Diversity Find People About NINDS NINDS Multiple Sclerosis Information Page Condensed from Multiple Sclerosis: Hope Through ... en Español Additional resources from MedlinePlus What is Multiple Sclerosis? An unpredictable disease of the central nervous system, ...

  7. Formation and tidal synchronization of sdB stars in binaries an asteroseismic investigation using Kepler Observations

    NASA Astrophysics Data System (ADS)

    Pablo, Herbert William

    Subdwarf B (sdB) stars are low mass (0.5 M sun) helium burning stars with thin hydrogen envelopes and Teff 22000-40000 K. Many of these stars are found in binary systems. One common proposed formation mechanism is common envelope (CE) ejection, where the companion spirals deep into the star's envelope ejecting the outer layers and forming a close binary system. In this dissertation, we use short cadence (tint=58.86 s) Kepler photometric time-series data to study three close sdB binaries with P ≈ 10 hours and g-mode pulsations. Asteroseismic analysis finds that each system has a constant period spacing of ΔP ≈ 250 s consistent with single sdB stars. This analysis also shows the presence of rotational multiplets which we used to find the rotation period. In all three cases the binary system is far from tidal synchronization with a rotation period an order of magnitude longer than the orbital period. These observations agree with predictions using the Zahn formulation of tidal evolution which predicts a synchronization time longer than the sdB lifetime (108 yr). We use this synchronization time to backtrack the sdB's rotation history and find its initial rotation period as it is first exiting the CE. This is one of the only observationally based constraints that has been placed on CE evolution. Preliminary investigations of single sdB stars show similar rotation periods, indicating that the rotation period may be independent of the formation channel.

  8. Discovery, characterization and in vivo activity of pyocin SD2, a protein antibiotic from Pseudomonas aeruginosa

    PubMed Central

    McCaughey, Laura C.; Josts, Inokentijs; Grinter, Rhys; White, Paul; Byron, Olwyn; Tucker, Nicholas P.; Matthews, Jacqueline M.; Kleanthous, Colin; Whitchurch, Cynthia B.; Walker, Daniel

    2016-01-01

    Increasing rates of antibiotic resistance among Gram-negative pathogens such as Pseudomonas aeruginosa means alternative approaches to antibiotic development are urgently required. Pyocins, produced by P. aeruginosa for intraspecies competition, are highly potent protein antibiotics known to actively translocate across the outer membrane of P. aeruginosa. Understanding and exploiting the mechanisms by which pyocins target, penetrate and kill P. aeruginosa is a promising approach to antibiotic development. In this work we show the therapeutic potential of a newly identified tRNase pyocin, pyocin SD2, by demonstrating its activity in vivo in a murine model of P. aeruginosa lung infection. In addition, we propose a mechanism of cell targeting and translocation for pyocin SD2 across the P. aeruginosa outer membrane. Pyocin SD2 is concentrated at the cell surface, via binding to the common polysaccharide antigen (CPA) of P. aeruginosa lipopolysaccharide (LPS), from where it can efficiently locate its outer membrane receptor FpvAI. This strategy of utilizing both the CPA and a protein receptor for cell targeting is common among pyocins as we show that pyocins S2, S5 and SD3 also bind to the CPA. Additional data indicate a key role for an unstructured N-terminal region of pyocin SD2 in the subsequent translocation of the pyocin into the cell. These results greatly improve our understanding of how pyocins target and translocate across the outer membrane of P. aeruginosa. This knowledge could be useful for the development of novel anti-pseudomonal therapeutics and will also support the development of pyocin SD2 as a therapeutic in its own right. PMID:27252387

  9. Discovery, characterization and in vivo activity of pyocin SD2, a protein antibiotic from Pseudomonas aeruginosa.

    PubMed

    McCaughey, Laura C; Josts, Inokentijs; Grinter, Rhys; White, Paul; Byron, Olwyn; Tucker, Nicholas P; Matthews, Jacqueline M; Kleanthous, Colin; Whitchurch, Cynthia B; Walker, Daniel

    2016-08-01

    Increasing rates of antibiotic resistance among Gram-negative pathogens such as Pseudomonas aeruginosa means alternative approaches to antibiotic development are urgently required. Pyocins, produced by P. aeruginosa for intraspecies competition, are highly potent protein antibiotics known to actively translocate across the outer membrane of P. aeruginosa. Understanding and exploiting the mechanisms by which pyocins target, penetrate and kill P. aeruginosa is a promising approach to antibiotic development. In this work we show the therapeutic potential of a newly identified tRNase pyocin, pyocin SD2, by demonstrating its activity in vivo in a murine model of P. aeruginosa lung infection. In addition, we propose a mechanism of cell targeting and translocation for pyocin SD2 across the P. aeruginosa outer membrane. Pyocin SD2 is concentrated at the cell surface, via binding to the common polysaccharide antigen (CPA) of P. aeruginosa lipopolysaccharide (LPS), from where it can efficiently locate its outer membrane receptor FpvAI. This strategy of utilizing both the CPA and a protein receptor for cell targeting is common among pyocins as we show that pyocins S2, S5 and SD3 also bind to the CPA. Additional data indicate a key role for an unstructured N-terminal region of pyocin SD2 in the subsequent translocation of the pyocin into the cell. These results greatly improve our understanding of how pyocins target and translocate across the outer membrane of P. aeruginosa. This knowledge could be useful for the development of novel anti-pseudomonal therapeutics and will also support the development of pyocin SD2 as a therapeutic in its own right. PMID:27252387

  10. Aquaporin 4-specific T cells and NMO-IgG cause primary retinal damage in experimental NMO/SD.

    PubMed

    Zeka, Bleranda; Hastermann, Maria; Kaufmann, Nathalie; Schanda, Kathrin; Pende, Marko; Misu, Tatsuro; Rommer, Paulus; Fujihara, Kazuo; Nakashima, Ichiro; Dahle, Charlotte; Leutmezer, Fritz; Reindl, Markus; Lassmann, Hans; Bradl, Monika

    2016-01-01

    Neuromyelitis optica/spectrum disorder (NMO/SD) is a severe, inflammatory disease of the central nervous system (CNS). In the majority of patients, it is associated with the presence of pathogenic serum autoantibodies (the so-called NMO-IgGs) directed against the water channel aquaporin 4 (AQP4), and with the formation of large, astrocyte-destructive lesions in spinal cord and optic nerves. A large number of recent studies using optical coherence tomography (OCT) demonstrated that damage to optic nerves in NMO/SD is also associated with retinal injury, as evidenced by retinal nerve fiber layer (RNFL) thinning and microcystic inner nuclear layer abnormalities. These studies concluded that retinal injury in NMO/SD patients results from secondary neurodegeneration triggered by optic neuritis.However, the eye also contains cells expressing AQP4, i.e., Müller cells and astrocytes in the retina, epithelial cells of the ciliary body, and epithelial cells of the iris, which raised the question whether the eye can also be a primary target in NMO/SD. Here, we addressed this point in experimental NMO/SD (ENMO) induced in Lewis rat by transfer of AQP4268-285-specific T cells and NMO-IgG.We show that these animals show retinitis and subsequent dysfunction/damage of retinal axons and neurons, and that this pathology occurs independently of the action of NMO-IgG. We further show that in the retinae of ENMO animals Müller cell side branches lose AQP4 reactivity, while retinal astrocytes and Müller cell processes in the RNFL/ganglionic cell layers are spared. These changes only occur in the presence of both AQP4268-285-specific T cells and NMO-IgG.Cumulatively, our data show that damage to retinal cells can be a primary event in NMO/SD. PMID:27503347

  11. Multiplicity Counting

    SciTech Connect

    Geist, William H.

    2015-12-01

    This set of slides begins by giving background and a review of neutron counting; three attributes of a verification item are discussed: 240Pueff mass; α, the ratio of (α,n) neutrons to spontaneous fission neutrons; and leakage multiplication. It then takes up neutron detector systems – theory & concepts (coincidence counting, moderation, die-away time); detector systems – some important details (deadtime, corrections); introduction to multiplicity counting; multiplicity electronics and example distributions; singles, doubles, and triples from measured multiplicity distributions; and the point model: multiplicity mathematics.

  12. Primordial SdS universe from a 5D vacuum: scalar field fluctuations on Schwarzschild and Hubble horizons

    SciTech Connect

    Aguilar, José Edgar Madriz; Bellini, Mauricio E-mail: mbellini@mdp.edu.ar

    2010-11-01

    We study scalar field fluctuations of the inflaton field in an early inflationary universe on an effective 4D Schwarzschild-de Sitter (SdS) metric, which is obtained after make a planar coordinate transformation on a 5D Ricci-flat Schwarzschild-de Sitter (SdS) static metric. We obtain the important result that the spectrum of fluctuations at zeroth order is independent of the scalar field mass M on Schwarzschild scales, while on cosmological scales it exhibits a mass dependence. However, in the first-order expansion, the spectrum depends of the inflaton mass and the amplitude is linear with the Black-Hole (BH) mass m.

  13. Heterologous Expression and Characterization of the Manganese-Oxidizing Protein from Erythrobacter sp. Strain SD21

    PubMed Central

    Nakama, Katherine; Medina, Michael; Lien, Ahn; Ruggieri, Jordan; Collins, Krystle

    2014-01-01

    The manganese (Mn)-oxidizing protein (MopA) from Erythrobacter sp. strain SD21 is part of a unique enzymatic family that is capable of oxidizing soluble Mn(II). This enzyme contains two domains, an animal heme peroxidase domain, which contains the catalytic site, followed by a C-terminal calcium binding domain. Different from the bacterial Mn-oxidizing multicopper oxidase enzymes, little is known about MopA. To gain a better understanding of MopA and its role in Mn(II) oxidation, the 238-kDa full-length protein and a 105-kDa truncated protein containing only the animal heme peroxidase domain were cloned and heterologously expressed in Escherichia coli. Despite having sequence similarity to a peroxidase, hydrogen peroxide did not stimulate activity, nor was activity significantly decreased in the presence of catalase. Both pyrroloquinoline quinone (PQQ) and hemin increased Mn-oxidizing activity, and calcium was required. The Km for Mn(II) of the full-length protein in cell extract was similar to that of the natively expressed protein, but the Km value for the truncated protein in cell extract was approximately 6-fold higher than that of the full-length protein, suggesting that the calcium binding domain may aid in binding Mn(II). Characterization of the heterologously expressed MopA has provided additional insight into the mechanism of bacterial Mn(II) oxidation, which will aid in understanding the role of MopA and Mn oxidation in bioremediation and biogeochemical cycling. PMID:25172859

  14. Improved determination of the atmospheric parameters of the pulsating sdB star Feige 48

    SciTech Connect

    Latour, M.; Fontaine, G.; Brassard, P.; Green, E. M.; Chayer, P.

    2014-06-10

    As part of a multifaceted effort to better exploit the asteroseismological potential of the pulsating sdB star Feige 48, we present an improved spectroscopic analysis of that star based on new grids of NLTE, fully line-blanketed model atmospheres. To that end, we gathered four high signal-to-noise ratio time-averaged optical spectra of varying spectral resolutions from 1.0 Å to 8.7 Å, and we made use of the results of four independent studies to fix the abundances of the most important metals in the atmosphere of Feige 48. The mean atmospheric parameters we obtained from our four spectra of Feige 48 are: T {sub eff} = 29,850 ± 60 K, log g = 5.46 ± 0.01, and log N(He)/N(H) = –2.88 ± 0.02. We also modeled, for the first time, the He II line at 1640 Å from the STIS archive spectrum of the star, and with this line we found an effective temperature and a surface gravity that match well with the values obtained with the optical data. With some fine tuning of the abundances of the metals visible in the optical domain, we were able to achieve a very good agreement between our best available spectrum and our best-fitting synthetic one. Our derived atmospheric parameters for Feige 48 are in rather good agreement with previous estimates based on less sophisticated models. This underlines the relatively small effects of the NLTE approach combined with line blanketing in the atmosphere of this particular star, implying that the current estimates of the atmospheric parameters of Feige 48 are reliable and secure.

  15. Purification and Characterization of the Manganese(II) Oxidizing Protein from Erythrobacter sp. SD-21

    NASA Astrophysics Data System (ADS)

    Nakama, K. R.; Lien, A.; Johnson, H. A.

    2013-12-01

    The manganese(II) oxidizing protein (Mop) found in the alpha-proteobacterium Erythrobacter sp. SD-21 catalyzes the formation of insoluble Mn(III/IV) oxides from soluble Mn(II). These Mn(III/IV) oxides formed are one of the strongest naturally occurring oxides, next to oxygen, and can be used to adsorb and oxidize toxic chemicals from the surrounding environment. Because of the beneficial use in the treatment of contaminated sources, the mechanism and biochemical properties of this novel enzyme are being studied. Due to low expression levels in the native host strain, purification of Mop has been problematic. To overcome this problem the gene encoding Mop, mopA, was cloned from the native host into a C-terminal histidine tag vector and expressed in Escherichia coli cells. Affinity chromatography under denaturing conditions have been applied in attempts to purify an active Mop. Western blots have confirmed that the protein is being expressed and is at the expected size of 250 kDa. Preliminary characterization on crude extract containing Mop has shown a Km and vmax value of 2453 uM and 0.025 uM min-1, respectively. Heme and pyrroloquinoline quinone can stimulate Mn(II) oxidizing activity, but hydrogen peroxide does not affect activity, despite the sequence similarity to animal heme peroxidase proteins. Research has been shown that calcium is essential for Mop activity. Purifying an active Mn(II) oxidizing protein will allow for a better understanding behind the enigmatic process of Mn(II) oxidation.

  16. Alleviating anastrozole induced bone toxicity by selenium nanoparticles in SD rats

    SciTech Connect

    Vekariya, Kiritkumar K.; Kaur, Jasmine; Tikoo, Kulbhushan

    2013-04-15

    Aromatase inhibitors like anastrozole play an undisputed key role in the treatment of breast cancer, but on the other hand, various side effects like osteoporosis and increased risk of bone fracture accompany the chronic administration of these drugs. Here we show for the first time that selenium nanoparticles, when given in conjugation to anastrozole, lower the bone toxicity caused by anastrozole and thus reduce the probable damage to the bone. Selenium nanoparticles at a dose of 5 μg/ml significantly reduced the cell death caused by anastrozole (1 μM) in HOS (human osteoblast) cells. In addition, our results also highlighted that in female SD rat model, SeNPs (0.25, 0.5, 1 mg/kg/day) significantly prevented the decrease in bone density and increase in biochemical markers of bone resorption induced by anastrozole (0.2 mg/kg/day) treatment. Histopathological examination of the femurs of SeNP treated group revealed ossification, mineralization, calcified cartilaginous deposits and a marginal osteoclastic activity, all of which indicate a marked restorative action, suggesting the protective action of the SeNPs. Interestingly, SeNPs (1 mg/kg/day) also exhibited protective effect in ovariectomized rat model, by preventing osteoporosis, which signifies that bone loss due to estrogen deficiency can be effectively overcome by using SeNPs. - Highlights: ► SeNPs significantly reduce bone toxicity in anastrozole treated rats. ► SeNPs successfully prevented osteoporosis in ovariectomized rats. ► SeNP treatment lowered the levels of TRAP and increased the levels of ALKP.

  17. Travel Times of Later Phases for Transmitting Waves through a Fracturing Westerly Granite Sample under a Triaxial Compressive Condition

    NASA Astrophysics Data System (ADS)

    Imahori, A.; Kawakata, H.; Hirano, S.; Yoshimitsu, N.; Takahashi, N.

    2015-12-01

    In laboratory, it is well-known that the elastic wave speed varies prior to compression fracture of the rock (e.g., Lockner et al., 1977, JGR). Using an enough number of travel times of elastic wave paths in a sample, we can estimate internal structure of the sample. However, the number of the elastic wave transducers is limited, and only the travel times of the first arrival are available in most experiments. Employing broadband transducers (Yoshimitsu et al., 2014, GRL), later phases become available to be analyzed. In the present study, we conduct a triaxial compressive test at room temperature under a dry condition and a confining pressure of 50 MPa, using a cylindrical Westerly granite sample of 100 mm long by 50 mm in diameter. Eight transducers are attached on the sample surface. One of the transducers is used as a wave source and voltage steps are repeatedly applied to it. The elastic waves passing through the sample are sensed by the other broadband transducers, and recorded at a sampling rate of 20 Msps. P-wave speed is estimated from the travel time of the direct P, and Vp/Vs value is assumed to be the √3 to give S-wave speed. We assume that all wave paths never bend except at the top and bottom surface of the sample. We calculate the travel times of later phases reflected at the top and/or bottom surfaces within 3 times. We collate the calculated travel times with observed waveforms. We can identify the travel time of two phases: single reflection from both top and bottom of the sample. On the other hand, some other observed and calculated phase arrivals do not match with each other. Then, we try to identify some remarkable phases using the calculated travel times of PS and SP converted waves and interfacial waves, taking into consideration of wave speed anisotropy.

  18. Phase-space transport in cuspy triaxial potentials: can they be used to construct self-consistent equilibria?

    NASA Astrophysics Data System (ADS)

    Siopis, Christos; Kandrup, Henry E.

    2000-11-01

    This paper focuses on the statistical properties of chaotic orbit ensembles evolved in triaxial generalizations of the Dehnen potential which have been proposed recently to model realistic ellipticals that have a strong density cusp and manifest significant deviations from axisymmetry. Allowance is made for a possible supermassive black hole, as well as low-amplitude friction, noise, and periodic driving which can mimic irregularities associated with discreteness effects and/or an external environment. The chaos exhibited by these potentials is quantified by determining (1) how the relative number of chaotic orbits depends on the steepness of the cusp, as probed by γ, the power-law exponent with which density diverges, and MBH, the black hole mass, (2) how the size of the largest Lyapunov exponent varies with γ and MBH, and (3) the extent to which Arnold webs significantly impede phase-space transport, both with and without perturbations. The most important conclusions dynamically are (1) that, in the absence of irregularities, chaotic orbits tend to be extremely `sticky', so that different pieces of the same chaotic orbit can behave very differently for times ~10000tD or more, but (2) that even very low-amplitude perturbations can prove efficient in erasing many - albeit not all - of these differences. The implications of these facts are discussed both for the structure and evolution of real galaxies and for the possibility of constructing approximate near-equilibrium models using Schwarzschild's method. For example, when trying to use Schwarzschild's method to construct model galaxies containing significant numbers of chaotic orbits, it seems advantageous to build libraries with chaotic orbits evolved in the presence of low-amplitude friction and noise, since such noisy orbits are more likely to represent reasonable approximations to time-independent building blocks. Much of the observed qualitative behaviour can be reproduced with a toy potential given as the

  19. Development of a Subcell Based Modeling Approach for Modeling the Architecturally Dependent Impact Response of Triaxially Braided Polymer Matrix Composites

    NASA Technical Reports Server (NTRS)

    Sorini, Chris; Chattopadhyay, Aditi; Goldberg, Robert K.; Kohlman, Lee W.

    2016-01-01

    Understanding the high velocity impact response of polymer matrix composites with complex architectures is critical to many aerospace applications, including engine fan blade containment systems where the structure must be able to completely contain fan blades in the event of a blade-out. Despite the benefits offered by these materials, the complex nature of textile composites presents a significant challenge for the prediction of deformation and damage under both quasi-static and impact loading conditions. The relatively large mesoscale repeating unit cell (in comparison to the size of structural components) causes the material to behave like a structure rather than a homogeneous material. Impact experiments conducted at NASA Glenn Research Center have shown the damage patterns to be a function of the underlying material architecture. Traditional computational techniques that involve modeling these materials using smeared homogeneous, orthotropic material properties at the macroscale result in simulated damage patterns that are a function of the structural geometry, but not the material architecture. In order to preserve heterogeneity at the highest length scale in a robust yet computationally efficient manner, and capture the architecturally dependent damage patterns, a previously-developed subcell modeling approach where the braided composite unit cell is approximated as a series of four adjacent laminated composites is utilized. This work discusses the implementation of the subcell methodology into the commercial transient dynamic finite element code LS-DYNA (Livermore Software Technology Corp.). Verification and validation studies are also presented, including simulation of the tensile response of straight-sided and notched quasi-static coupons composed of a T700/PR520 triaxially braided [0deg/60deg/-60deg] composite. Based on the results of the verification and validation studies, advantages and limitations of the methodology as well as plans for future work

  20. Validity of Using Tri-Axial Accelerometers to Measure Human Movement - Part I: Posture and Movement Detection

    PubMed Central

    Lugade, Vipul; Fortune, Emma; Morrow, Melissa; Kaufman, Kenton

    2013-01-01

    A robust method for identifying movement in the free-living environment is needed to objectively measure physical activity. The purpose of this study was to validate the identification of postural orientation and movement from acceleration data against visual inspection from video recordings. Using tri-axial accelerometers placed on the waist and thigh, static orientations of standing, sitting, and lying down, as well as dynamic movements of walking, jogging and transitions between postures were identified. Additionally, subjects walked and jogged at self-selected slow, comfortable, and fast speeds. Identification of tasks was performed using a combination of the signal magnitude area, continuous wavelet transforms and accelerometer orientations. Twelve healthy adults were studied in the laboratory, with two investigators identifying tasks during each second of video observation. The intraclass correlation coefficients for inter-rater reliability were greater than 0.95 for all activities except for transitions. Results demonstrated high validity, with sensitivity and positive predictive values of greater than 85% for sitting and lying, with walking and jogging identified at greater than 90%. The greatest disagreement in identification accuracy between the algorithm and video occurred when subjects were asked to fidget while standing or sitting. During variable speed tasks, gait was correctly identified for speeds between 0.1m/s and 4.8m/s. This study included a range of walking speeds and natural movements such as fidgeting during static postures, demonstrating that accelerometer data can be used to identify orientation and movement among the general population. PMID:23899533

  1. Investigating Forearc Strength by Triaxial Testing of Marine Sediments from the Costa Rica Seismogenesis Project (IODP Expeditions 334 and 344)

    NASA Astrophysics Data System (ADS)

    Stipp, M.; Kurzawski, R. M.; Doose, R.; Schulte-Kortnack, D.

    2015-12-01

    Forearc stability and inherent tectonic failure processes at active continental margins very much depend on the strength of the composing sediments. Forearc sediments can either be prone to fracturing and more localized deformation or alternatively to creep and distributed deformation. Strength and deformation behavior can vary significantly depending on small differences in composition and fabric of the sediments as has been shown in a similar study on samples from the Nankai trench and forearc (Stipp et al., 2013). Cylindrical core samples with diameters of 30 and 50 mm recovered during IODP Expeditions 334 and 344 from a depth range of 7-788 m below sea floor were experimentally deformed in two different triaxial deformation apparatus under consolidated and undrained conditions at confining pressures of 0.4-20 MPa, room temperature, variable axial displacement rates of ~0.01-0.5 mm/min, and up to axial compressive strains of ~50%. Experimental results show great differences in the consolidation state and the related mechanical behavior of upper plate and incoming plate sediments. Similar to previous findings from the Nankai trench and forearc, structurally weak and structurally strong samples can be distinguished. One sample from shallow depth in the incoming plate shows a transition from structurally strong to structurally weak behavior with increasing confining pressure that has not been observed for Nankai samples. The differences in mechanical behavior may be the key for strain localization, faulting and surface breakage at active erosive as well as accretionary continental margins. Reference: Stipp, M., Rolfs, M., Kitamura, Y., Behrmann, J.H., Schumann, K., Schulte-Kortnack, D. and Feeser, V. (2013). - Geochemistry, Geophysics, Geosystems 14/11, doi: 10.1002/ggge.20290.

  2. Fracture and Consequences of Caprock and Cement Observed by Integrated Triaxial Coreflood and X-ray Tomography

    NASA Astrophysics Data System (ADS)

    Carey, J. W.; Frash, L.

    2015-12-01

    Mechanical damage to caprock and wellbore systems threatens the long-term integrity of CO2 storage reservoirs. While it is widely recognized that CO2 injection can generate damage-causing stresses, there is little information on the hydrologic consequences of the resulting fractures in terms of the magnitude of potential CO2 leakage. In this study, we perform experiments at reservoir conditions designed to fracture caprock and cement while simultaneously observing changes in permeability coupled with direct observation of fracture growth using x-ray video radiography and fracture geometry by x-ray tomography. Triaxial coreflood experiments using a direct-shear configuration were performed at confining pressures ranging from 3-22 MPa at 20 oC. Permeability was strongly dependent on confining pressure but also on the orientation of the fractures in relation to bedding. Samples fractured at high confining pressures had low permeability (typically <0.1 mD). Samples fractured at low confining pressures had permeabilities that ranged from 10s of mD across bedding to as high as 1 D parallel to bedding. Video radiography was collected through observations parallel to the direct shear plane. These captured the rate of fracture growth (on the order of seconds) and were used in relation to the onset of elevated permeability to investigate fracture-permeability dynamics. X-ray tomography was conducted at pressure but under static conditions and showed that fracture apertures at high confining pressures were significantly smaller than fracture apertures recovered at atmospheric conditions. Preliminary results suggest that increasing material plasticity accompanying high confining pressures resulted in decreased permeability, smaller apertures, and more poorly connected fracture networks. Typical sequestration conditions correspond to the higher confining pressures used in this study, suggesting that the failure characteristics of caprock and cement may be capable of limiting

  3. Validity of using tri-axial accelerometers to measure human movement - Part I: Posture and movement detection.

    PubMed

    Lugade, Vipul; Fortune, Emma; Morrow, Melissa; Kaufman, Kenton

    2014-02-01

    A robust method for identifying movement in the free-living environment is needed to objectively measure physical activity. The purpose of this study was to validate the identification of postural orientation and movement from acceleration data against visual inspection from video recordings. Using tri-axial accelerometers placed on the waist and thigh, static orientations of standing, sitting, and lying down, as well as dynamic movements of walking, jogging and transitions between postures were identified. Additionally, subjects walked and jogged at self-selected slow, comfortable, and fast speeds. Identification of tasks was performed using a combination of the signal magnitude area, continuous wavelet transforms and accelerometer orientations. Twelve healthy adults were studied in the laboratory, with two investigators identifying tasks during each second of video observation. The intraclass correlation coefficients for inter-rater reliability were greater than 0.95 for all activities except for transitions. Results demonstrated high validity, with sensitivity and positive predictive values of greater than 85% for sitting and lying, with walking and jogging identified at greater than 90%. The greatest disagreement in identification accuracy between the algorithm and video occurred when subjects were asked to fidget while standing or sitting. During variable speed tasks, gait was correctly identified for speeds between 0.1m/s and 4.8m/s. This study included a range of walking speeds and natural movements such as fidgeting during static postures, demonstrating that accelerometer data can be used to identify orientation and movement among the general population. PMID:23899533

  4. 76 FR 58241 - Designation for the Aberdeen, SD; Decatur, IL; Hastings, NE; Fulton, IL; the State of Missouri...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-20

    ..., Federal Register (76 FR 15937), GIPSA requested applications for designation to provide official services... Grain Inspection, Packers and Stockyards Administration Designation for the Aberdeen, SD; Decatur, IL; Hastings, NE; Fulton, IL; the State of Missouri, and the State of South Carolina Areas AGENCY:...

  5. Application of chirally-deuterated (S)-D-(6-2H1)glucose to conformational studies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Deuterated sugars are widely used to elucidate mechanisms of biosynthesis and of chemical reactions, and to confirm assignments of complex NMR or mass spectra. To date, however, there are few reported syntheses for regio and stereospecifically deuterated pyranoses. Chirally-deuterated (S)-D-(6-**2...

  6. 40 CFR Table 28 to Subpart G of... - Deck Seam Length Factors a (SD) for Internal Floating Roof Tanks

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Deck Seam Length Factors a (SD) for Internal Floating Roof Tanks 28 Table 28 to Subpart G of Part 63 Protection of Environment ENVIRONMENTAL... specific information is available, these factors can be assumed to represent the most common bolted...

  7. Identification of a New Marine Bacterial Strain SD8 and Optimization of Its Culture Conditions for Producing Alkaline Protease.

    PubMed

    Cui, Hongxia; Yang, Muyang; Wang, Liping; Xian, Cory J

    2015-01-01

    While much attention has been given to marine microorganisms for production of enzymes, which in general are relatively more stable and active compared to those from plants and animals, studies on alkaline protease production from marine microorganisms have been very limited. In the present study, the alkaline protease producing marine bacterial strain SD8 isolated from sea muds in the Geziwo Qinhuangdao sea area of China was characterized and its optimal culture conditions were investigated. Strain SD8 was initially classified to belong to genus Pseudomonas by morphological, physiological and biochemical characterizations, and then through 16S rDNA sequence it was identified to be likely Pseudomonas hibiscicola. In addition, the culture mediums, carbon sources and culture conditions of strain SD8 were optimized for maximum production of alkaline protease. Optimum enzyme production (236U/mL when cultured bacteria being at 0.75 mg dry weight/mL fermentation broth) was obtained when the isolate at a 3% inoculum size was grown in LB medium at 20 mL medium/100mL Erlenmeyer flask for 48h culture at 30°C with an initial of pH 7.5. This was the first report of strain Pseudomonas hibiscicola secreting alkaline protease, and the data for its optimal cultural conditions for alkaline protease production has laid a foundation for future exploration for the potential use of SD8 strain for alkaline protease production.

  8. Rapid, accurate, and non-invasive measurement of zebrafish axial length and other eye dimensions using SD-OCT allows longitudinal analysis of myopia and emmetropization.

    PubMed

    Collery, Ross F; Veth, Kerry N; Dubis, Adam M; Carroll, Joseph; Link, Brian A

    2014-01-01

    Refractive errors in vision can be caused by aberrant axial length of the eye, irregular corneal shape, or lens abnormalities. Causes of eye length overgrowth include multiple genetic loci, and visual parameters. We evaluate zebrafish as a potential animal model for studies of the genetic, cellular, and signaling basis of emmetropization and myopia. Axial length and other eye dimensions of zebrafish were measured using spectral domain-optical coherence tomography (SD-OCT). We used ocular lens and body metrics to normalize and compare eye size and relative refractive error (difference between observed retinal radial length and controls) in wild-type and lrp2 zebrafish. Zebrafish were dark-reared to assess effects of visual deprivation on eye size. Two relative measurements, ocular axial length to body length and axial length to lens diameter, were found to accurately normalize comparisons of eye sizes between different sized fish (R2=0.9548, R2=0.9921). Ray-traced focal lengths of wild-type zebrafish lenses were equal to their retinal radii, while lrp2 eyes had longer retinal radii than focal lengths. Both genetic mutation (lrp2) and environmental manipulation (dark-rearing) caused elongated eye axes. lrp2 mutants had relative refractive errors of -0.327 compared to wild-types, and dark-reared wild-type fish had relative refractive errors of -0.132 compared to light-reared siblings. Therefore, zebrafish eye anatomy (axial length, lens radius, retinal radius) can be rapidly and accurately measured by SD-OCT, facilitating longitudinal studies of regulated eye growth and emmetropization. Specifically, genes homologous to human myopia candidates may be modified, inactivated or overexpressed in zebrafish, and myopia-sensitizing conditions used to probe gene-environment interactions. Our studies provide foundation for such investigations into genetic contributions that control eye size and impact refractive errors.

  9. Rapid, Accurate, and Non-Invasive Measurement of Zebrafish Axial Length and Other Eye Dimensions Using SD-OCT Allows Longitudinal Analysis of Myopia and Emmetropization

    PubMed Central

    Collery, Ross F.; Veth, Kerry N.; Dubis, Adam M.; Carroll, Joseph; Link, Brian A.

    2014-01-01

    Refractive errors in vision can be caused by aberrant axial length of the eye, irregular corneal shape, or lens abnormalities. Causes of eye length overgrowth include multiple genetic loci, and visual parameters. We evaluate zebrafish as a potential animal model for studies of the genetic, cellular, and signaling basis of emmetropization and myopia. Axial length and other eye dimensions of zebrafish were measured using spectral domain-optical coherence tomography (SD-OCT). We used ocular lens and body metrics to normalize and compare eye size and relative refractive error (difference between observed retinal radial length and controls) in wild-type and lrp2 zebrafish. Zebrafish were dark-reared to assess effects of visual deprivation on eye size. Two relative measurements, ocular axial length to body length and axial length to lens diameter, were found to accurately normalize comparisons of eye sizes between different sized fish (R2 = 0.9548, R2 = 0.9921). Ray-traced focal lengths of wild-type zebrafish lenses were equal to their retinal radii, while lrp2 eyes had longer retinal radii than focal lengths. Both genetic mutation (lrp2) and environmental manipulation (dark-rearing) caused elongated eye axes. lrp2 mutants had relative refractive errors of −0.327 compared to wild-types, and dark-reared wild-type fish had relative refractive errors of −0.132 compared to light-reared siblings. Therefore, zebrafish eye anatomy (axial length, lens radius, retinal radius) can be rapidly and accurately measured by SD-OCT, facilitating longitudinal studies of regulated eye growth and emmetropization. Specifically, genes homologous to human myopia candidates may be modified, inactivated or overexpressed in zebrafish, and myopia-sensitizing conditions used to probe gene-environment interactions. Our studies provide foundation for such investigations into genetic contributions that control eye size and impact refractive errors. PMID:25334040

  10. TGF-β-RI Kinase Inhibitor SD-208 Reduces the Development and Progression of Melanoma Bone Metastases

    PubMed Central

    Mohammad, Khalid S.; Javelaud, Delphine; Fournier, Pierrick G. J.; Niewolna, Maria; McKenna, C. Ryan; Peng, Xiang H.; Duong, Vu; Dunn, Lauren K.; Mauviel, Alain; Guise, Theresa A.

    2010-01-01

    Melanoma often metastasizes to bone where it is exposed to high concentrations of TGF-β. Constitutive Smad signaling occurs in human melanoma. Because TGF-β promotes metastases to bone by several types of solid tumors including breast cancer, we hypothesized that pharmacologic blockade of the TGF-β signaling pathway may interfere with the capacity of melanoma cells to metastasize to bone. In this study, we tested the effect of a small molecule inhibitor of TGF-β receptor I kinase (TβRI), SD-208, on various parameters affecting the development and progression of melanoma, both in vitro and in a mouse model of human melanoma bone metastasis. In melanoma cell lines, SD-208 blocked TGF-β induction of Smad3 phosphorylation, Smad3/4-specific transcription, Matrigel invasion and expression of the TGF-β target genes PTHrP, IL-11, CTGF and RUNX2. To assess effects of SD-208 on melanoma development and metastasis, nude mice were inoculated with 1205Lu melanoma cells into the left cardiac ventricle and drug was administered by oral gavage on prevention or treatment protocols. SD-208 (60mg/kg/day), started 2 days before tumor inoculation prevented the development of osteolytic bone metastases compared with vehicle. In mice with established bone metastases, the size of osteolytic lesions was significantly reduced after 4 weeks treatment with SD-208 compared to vehicle-treated mice. Our results demonstrate that therapeutic targeting of TGF-β may prevent the development of melanoma bone metastases and decrease the progression of established osteolytic lesions. PMID:21084275

  11. Growth of (Y1-x Ca x )Ba2Cu4O8 in ambient pressure and its tri-axial magnetic alignment

    NASA Astrophysics Data System (ADS)

    Horii, S.; Yamaki, M.; Shimoyama, J.; Kishio, K.; Doi, T.

    2015-10-01

    We report the growth of single crystals in ambient pressure and tri-axial orientation under modulated rotation magnetic fields (MRFs) for (Y1-x Ca x )Ba2Cu4O8 [(Y1-x Ca x )124] with x ≤ 0.1. Rectangular (Y1-x Ca x )124 crystals approximately 50 μm in size have been successfully grown for x ≤ 0.1 in a growth temperature region from 650 °C to 750 °C. Their critical temperatures increased with x and exhibited approximately 91 K for x = 0.1. By applying an MRF of 10 T, pulverised powders of (Y1-x Ca x )124 were tri-axially aligned in epoxy resin at room temperature in a whole x region below x = 0.1. The magnitude relationship of the magnetic susceptibilities (χ) along crystallographic directions for (Y1-x Ca x )124 was χ c > χ a > χ b at room temperature and was unchanged with a change in x. From changes in the degrees of the c-axis and the in-plane orientation (Δω) for the (Y1-x Ca x )124 powder samples aligned under three different MRF conditions, it was found that MRFs above at least 1 T were required to achieve almost complete tri-axial alignment with Δω < 5°. Irreversibility lines for H//c were successfully determined even from the powder samples by the introduction of magnetic alignment without using single crystalline samples. The present study indicates that magnetic alignment is a useful process for the fabrication of quasi-single-crystals from the perspective of solid-state physics and the production of cuprate superconducting materials.

  12. Representing Multiplication

    ERIC Educational Resources Information Center

    Harries, Tony; Barmby, Patrick

    2008-01-01

    In this study, the authors wish to explore the use of visual representations in facilitating the understanding of multiplication. In doing so, they examine the different aspects of multiplication that they can access through different representations. In addition, they draw on a study that they have been carrying out looking at pupils' actual use…

  13. Further comments on the application of the method of averaging to the study of the rotational motions of a triaxial rigid body, part 3

    NASA Technical Reports Server (NTRS)

    Liu, J. J. F.; Fitzpatrick, P. M.

    1973-01-01

    Variational equations were applied to the case of a rapidly spinning triaxial body moving in an elliptic orbit, in which the orbital plane is regressing at a constant rate. The explicit differential equations obtained in this application were integrated by the method of averaging to develop secular analytical expressions, which, to first-order in a small parameter, describe the complete space motions of the rigid body under the influence of nonresonant gravity-gradient perturbations. The effects of aerodynamic torque on the rotational motion of an orbiting satellite are studied, as another example of the application of the variational equations derived and the method of averaging.

  14. Southern galaxies. VIII - Surface photometry of the SD spiral NGC 7793

    NASA Astrophysics Data System (ADS)

    de Vaucouleurs, G.; Davoust, E.

    1980-08-01

    Detailed surface photometry in blue light of the SA(s)d galaxy NGC 7793, the faintest of the five major members of the Sculptor group, is obtained from photoelectrically calibrated Mount Stromlo and McDonald photographs. The luminosity distribution is dominated by an exponential disk of effective radius αe = 2'.11 = 1.92 kpc contributing 98.6% of the total luminosity BT = 9.51 ± 0.06. The corrected face-on magnitude BT0 = 9.13 corresponds to MT0 = -18.35 at the revised distance Δ = 3.1 Mpc (Appendix C). The spheroidal component visible only in the vicinity of the nucleus can be represented by an r1/4 law of effective radius rIe = 6".0 = 91 pc and total magnitude BTI = 14.13 or 1.4% of the total luminosity of the galaxy. The position angle of the major axis is 97°, the mean axis ratio is q = b/a = 0.61, and the inclination = 53°. The concentration indices C21 = 1.68 and C32 = 1.48 are consistent with the Sd classification. The integrated colors from UBV aperture photometry are essentially constant at = 0.56 ± 0.02, = -0.07 ± 0.02, the corrected face-on colors are (B - V)T0 = 0.46, (U - B)T0 = -0.15 in close agreement with the colors of M33 and the mean values for type Scd. A decomposition of the disk into an underlying old component and a young arm component shows that 65.570 of the total luminosity comes from the old component which has a corrected central luminosity μcα(0) = 21.06 and an effective radius re = 1'.76 = 1.60 kpc. The neutral H I mass MH = 0.67 × 109 Msun corresponds to a hydrogen-luminosity ratio MH/LB = 0.14 which is less than half the average for the morphological type and luminosity class of NGC 7793. The large number of H ii regions and the strength of the Hα emission in the disk suggest that a large fraction of the hydrogen is ionized. The integrated magnitude of the brightest superassociation (Hodge Nr 20) B, = 16.0 ± 0.1 is derived in Appendix A. The effect of resolution on the apparent peak brightness is illustrated in Appendix B

  15. Deformation and Brittle Failure of Folded Gneiss in Triaxial Compression: Failure Modes, Acoustic Signatures and Microfabric Controls

    NASA Astrophysics Data System (ADS)

    Agliardi, F.; Vinciguerra, S.; Dobbs, M. R.; Zanchetta, S.

    2014-12-01

    Fabric anisotropy is a key control of rock behavior in different geological settings and over different timescales. However, the effect of tectonically folded fabrics on the brittle strength and failure mode of metamorphic rocks is poorly understood. Recent data, obtained from uniaxial compression experiments on folded gneiss (Agliardi et al., 2014), demonstrated that their brittle failure modes depend upon the arrangement of two anisotropies (i.e. foliation and fold axial planes) and that rock strength correlates with failure mode. Since lithostatic pressure may significantly affect this rock behavior, we investigated its effect in triaxial compression experiments. We tested the Monte Canale Gneiss (Italian Alps), characterized by low phyllosilicate content and compositional layering folded at the cm-scale. We used a servo-controlled hydraulic loading system to test 19 air-dry cylindrical specimens (ø = 54 mm) that were characterized both in terms of fold geometry and orientation of foliation and fold axial planes to the axial load direction. The specimens were instrumented with direct contact axial and circumferential strain gauges. Acoustic emissions and P- and S-wave velocities were measured by piezoelectric transducers mounted in the compression platens. The tests were performed at confining pressures of 40 MPa and axial strain rates of 5*10-6 s-1. Post-failure study of fracture mechanisms and related microfabric controls was undertaken using X-ray CT, optical microscopy and SEM. Samples failed in three distinct brittle modes produced by different combinations of fractures parallel to foliation, fractures parallel to fold axial planes, or mm-scale shear bands. The failure modes, consistent with those described in uniaxial compression experiments, were found to be associated with distinct stress-strain and acoustic emission signatures. Failure modes involving quartz-dominated axial plane anisotropy correspond to higher peak strength and axial strain, less

  16. Triaxial modulation of the acceleration induced in the lower extremity during whole-body vibration training: a pilot study.

    PubMed

    Cook, David P; Mileva, Katya N; James, Darren C; Zaidell, Lisa N; Goss, Victor G; Bowtell, Joanna L

    2011-02-01

    The purpose of the present study was to quantify vibration transmissibility through the lower extremity during exercise on a whole-body vibration (WBV) platform. Six healthy adults completed 20 trials of 30-second static squat exercise at 30 or 40 degrees of knee flexion angle on a WBV platform working at combinations of 5 frequencies (VF: 20, 25, 30, 35, 40 Hz) and 2 amplitudes (VA: low, 1.5 mm or high, 3 mm). Accelerations induced by the platform were recorded simultaneously at the shank and the thigh using triaxial accelerometers positioned at the segmental center of mass. Root-mean-square (RMS) acceleration amplitude and transmission ratios between the platform and the leg segments were calculated and compared between the experimental conditions. An alpha level of 0.05 was set to establish significance. Shank vertical acceleration was greatest at the lower VF (p = 0.028), higher VA (p = 0.028), and deeper squat (p = 0.048). Thigh vertical acceleration was not affected by depth of squat (p = 0.25), but it was greatest at higher VA (p = 0.046) and lower VF (p = 0.028). Medial-lateral shank acceleration was greatest at higher VF and deeper squat (both p = 0.046) and at higher VA (p = 0.028). Medial-lateral thigh acceleration was positively related to both VF (p = 0.046) and VA (p = 0.028) but was not affected by knee angle (p = 0.46). Anterior-posterior shank acceleration was higher at deeper squat (p = 0.046) and at lower VF and higher VA (both p = 0.028). Anterior-posterior thigh acceleration was related positively to the VA (p = 0.028), inversely to the VF (p = 0.028), and not dependent on knee angle (p = 0.75). Identification of specific vibration parameters and posture, which underpin WBV training efficacy, will enable coaches and athletes to design WBV training programs to specifically target shank or thigh muscles for enhanced performance.

  17. Multiple homicides.

    PubMed

    Copeland, A R

    1989-09-01

    A study of multiple homicides or multiple deaths involving a solitary incident of violence by another individual was performed on the case files of the Office of the Medical Examiner of Metropolitan Dade County in Miami, Florida, during 1983-1987. A total of 107 multiple homicides were studied: 88 double, 17 triple, one quadruple, and one quintuple. The 236 victims were analyzed regarding age, race, sex, cause of death, toxicologic data, perpetrator, locale of the incident, and reason for the incident. This article compares this type of slaying with other types of homicide including those perpetrated by serial killers. Suggestions for future research in this field are offered.

  18. An X-Ray, Optical, and Radio Search for Supernova Remnants in the Nearby Sculptor Group Sd Galaxy NGC 7793

    NASA Astrophysics Data System (ADS)

    Pannuti, Thomas G.; Duric, Nebojsa; Lacey, Christina K.; Ferguson, Annette M. N.; Magnor, Marcus A.; Mendelowitz, Caylin

    2002-02-01

    This paper is the second in a series devoted to examining the multiwavelength properties of supernova remnants (SNRs) located in nearby galaxies. We consider here the resident SNRs in the nearby Sculptor group Sd galaxy NGC 7793. Using our own Very Large Array (VLA) radio observations at 6 and 20 cm, as well as archived ROSAT X-ray data, previously published optical results, and our own Hα image, we have searched for X-ray and radio counterparts to previously known optically identified SNRs and for new previously unidentified SNRs at these two wavelength regimes. Consistent with our prior results for NGC 300, only a tiny minority of the optically identified SNRs have been found at another wavelength. The most noteworthy source in our study is N7793-S26, which is the only SNR in this galaxy that is detected at all three wavelengths (X-ray, optical, and radio). It features a long (~450 pc) filamentary morphology that is clearly seen in both the optical and the radio images. N7793-S26's radio luminosity exceeds that of the Galactic SNR Cas A, and based on equipartition calculations we determine that an energy of at least 1052 ergs is required to maintain this source. Such a result argues for the source being created by multiple supernova explosions rather than by a single supernova event. A second optically identified SNR, N7793-S11, has detectable radio emission but no detectable X-ray emission. A radio-selected sample of candidate SNRs has also been prepared by searching for coincidences between nonthermal radio sources and regions of Hα emission in this galaxy. This search has produced five new candidate radio SNRs to be added to the 28 SNRs that have already been detected by optical methods. A complementary search for new candidate X-ray SNRs has also been conducted by searching for soft-spectrum sources (kT<1 keV) that are coincident with regions of Hα emission. That search has yielded a candidate X-ray SNR that is coincident with one (and possibly two) of the

  19. Systematics of band moment of inertia of yrast and excited SD bands of even-even nuclei in A~150 mass region

    NASA Astrophysics Data System (ADS)

    Sharma, Neha; Mittal, H. M.

    2015-07-01

    A four parameter formula has been applied to all the yrast and excited superdeformed (SD) bands of even-even nuclei in the A 150 mass region to obtain band moment of inertia J0. In even-even nuclei, totally three yrast SD bands and 16 excited SD bands have been fitted. The measured Qt values and hence the axes ratios have been used to calculate the rigid body J0 values and compared with the fitted values of J0. It is interesting to look at the yrast SD band 152Dy(1), the doubly magic SD nucleus and the first one to be discovered that the J0 values are quite larger than that extracted from Qt measurement. We found that all the excited SD bands in even-even nuclei are signature partner SD bands because the J0 value of each signature partner SD band is almost identical. Among all these excited SD bands, 150Gd(4) is found to be super-rigid in nature having J0 value larger than that observed from the measured Qt value.

  20. Data Qualification and Data Summary Report: Intact Rock Properties Data on Tensile Strength, Schmidt Hammer Rebound Hardness, and Rock Triaxial Creep

    SciTech Connect

    E.M. Cikanek; R.J. Blakely; T.A. Grant; L.E. Safley

    2003-07-29

    This report presents a systematic review of the available data in the TDMS that are relevant to the following intact rock properties: rock tensile strength, Schmidt hammer rebound hardness, and rock triaxial creep. Relevant data are compiled from qualified and unqualified sources into the summary DTNs and these DTNs are evaluated for qualification using the method of corroborating data as defined in AP-SIII.2Q, ''Qualification of Unqualified Data''. This report also presents a summary of the compiled information in the form of descriptive statistics and recommended values that will be contained in a Reference Information Base (RIB) item prepared in accordance with AP-SIII.4Q, ''Development, Review, Online Placement, and Maintenance of Individual Reference Information Base Data Items''. The primary purpose of this report is to produce qualified sets of data that include all relevant intact rock tensile strength, Schmidt hammer rebound hardness, and rock triaxial creep testing done over the course of the Yucca Mountain Project (YMP). A second purpose is to provide a qualified summary (i.e., a RIB data item) of the test results using descriptive statistics. The immediate purpose of the report is to support the data needs of repository design; however, the products are designed to be appropriate for general use by the YMP. The appropriateness and limitations, if any, of the data, with respect to the intended use, are addressed in this report.

  1. A real-time and self-calibrating algorithm based on triaxial accelerometer signals for the detection of human posture and activity.

    PubMed

    Curone, Davide; Bertolotti, Gian Mario; Cristiani, Andrea; Secco, Emanuele Lindo; Magenes, Giovanni

    2010-07-01

    Assessment of human activity and posture with triaxial accelerometers provides insightful information about the functional ability: classification of human activities in rehabilitation and elderly surveillance contexts has been already proposed in the literature. In the meanwhile, recent technological advances allow developing miniaturized wearable devices, integrated within garments, which may extend this assessment to novel tasks, such as real-time remote surveillance of workers and emergency operators intervening in harsh environments. We present an algorithm for human posture and activity-level detection, based on the real-time processing of the signals produced by one wearable triaxial accelerometer. The algorithm is independent of the sensor orientation with respect to the body. Furthermore, it associates to its outputs a "reliability" value, representing the classification quality, in order to launch reliable alarms only when effective dangerous conditions are detected. The system was tested on a customized device to estimate the computational resources needed for real-time functioning. Results exhibit an overall 96.2% accuracy when classifying both static and dynamic activities.

  2. Focal thinning of the cerebral cortex in multiple sclerosis.

    PubMed

    Sailer, Michael; Fischl, Bruce; Salat, David; Tempelmann, Claus; Schönfeld, Mircea Ariel; Busa, Evelina; Bodammer, Nils; Heinze, Hans-Jochen; Dale, Anders

    2003-08-01

    Brain atrophy as determined by quantitative MRI can be used to characterize disease progression in multiple sclerosis. Many studies have addressed white matter (WM) alterations leading to atrophy, while changes of the cerebral cortex have been studied to a lesser extent. In vivo, the cerebral cortex has been difficult to study due to its complex structure and regional variability. Measurement of cerebral cortex thickness at different disease stages may provide new insights into grey matter (GM) pathology. In the present investigation, we evaluated in vivo cortical thickness and its relationship to disability, disease duration, WM T2 hyper-intense and T1 hypo-intense lesion volumes. High-resolution MRI brain scans were obtained in 20 patients with clinically definite multiple sclerosis and 15 age-matched normal subjects. A novel method of automated surface reconstruction yielded measurements of the cortical thickness for each subject's entire brain and computed cross-subject statistics based on the cortical anatomy. Statistical thickness difference maps were generated by performing t-tests between patient and control groups and individual thickness measures were submitted to analyses of variance to investigate the relationship between cortical thickness and clinical variables. The mean overall thickness of the cortical ribbon was reduced in multiple sclerosis patients compared with controls [2.30 mm (SD 0.14) versus 2.48 mm (SD 0.11)], showing a significant main effect of group (controls versus patients). In patients, we found significant main effects for disability, disease duration, T2 and T1 lesion volumes. The visualization of statistical difference maps of the cortical GM thickness on inflated brains across the cortical surface revealed a distinct distribution of significant focal thinning of the cerebral cortex in addition to the diffuse cortical atrophy. Focal cortical thinning in frontal [2.37 mm (SD 0.17) versus 2.73 mm (SD 0.25)] and in temporal [2.65 mm

  3. Evaluation of antitumor activity of a TGF-beta receptor I inhibitor (SD-208) on human colon adenocarcinoma

    PubMed Central

    2014-01-01

    Background Transforming growth factor-β (TGF-β) pathway is involved in primary tumor progression and in promoting metastasis in a considerable proportion of human cancers such as colorectal cancer (CRC). Therefore, blockage of TGF-β pathway signaling via an inhibitor could be a valuable tool in CRC treatment. Methods To evaluate the efficacy of systemic targeting of the TGF-β pathway for therapeutic effects on CRC, we investigated the effects of a TGβRI (TGF-β receptor 1) or TβRI kinase inhibitor, SD-208, on SW-48, colon adenocarcinoma cells. In this work, in vitro cell proliferation was studied by methyl thiazolyl tetrazolium (MTT) and bromo-2′-deoxyuridine (BrdU) assays. Also, the histopathological and immunohistochemical evaluations were conducted by hematoxylin and eosin, and Ki-67 and CD34 markers were stained, respectively. Results Our results showed no significant reduction in cell proliferation and vessel formation (170 ± 70 and 165 ± 70, P > 0.05) in treated SW-48 cells with SD-208 compared to controls. Conclusion Our data suggested that SD-208 could not significantly reduce tumor growth and angiogenesis in human colorectal cancer model at least using SW-48 cells. PMID:24902843

  4. Fatty Acid Composition of Adipose Tissues in Obese Mice and SD Rats Fed with Isaria sinclairii Powder

    PubMed Central

    Ahn, Mi Young; Seo, Yun Jung; Ji, Sang Deok; Han, Jea Woong; Hwang, Jae Sam; Yun, Eun Young

    2010-01-01

    Isaria sinclairii (Cicada Dongchunghacho) was studied as a potential crude natural food in powdered form. The role of tissue fatty acids in relation to the anti-obesity effects of I. sinclairii (IS) was examined by feeding the powder to SD rats ad libitum at 0, 1.25, 2.5, 5 and 10% (calculated about 8 g/kg) of the feed for a period of 3 months and 6 months. The fatty acid composition profile as indicated GC-MS, showed significantly slight dose-dependent increases in the levels of unsaturated fatty acids, particularly, arachidonic acid (C20: 4n6) , oleic acid, linoleic acid, eicosadienoic acid, eicosapentaenoic acid (EPA) (C20: 5) concentration in the the ad libitum IS-fed groups compared to the control group in SD abdominal fat over 6 month period. Over viewing of the SD and Ob mice treated Isaria sinclairii powder; there were increases in the single (mono) unsaturated fatty acids ratio but decreases in polyunsaturated fatty acid. In IS-fed groups in proportion to the treatment period, this Dongchunghacho also induced an increase in the level of same result of unsaturated fatty acid in C57BL/6 obese (ob/ob) mice over a 6-month period treatment compared to those given 10% dry mulberry leaf powder (ML) or silkworm powder mixed with the standard diet. PMID:24278523

  5. [Glucose transponer type 1 deficiency síndrome (GLUT-1 SD) treated with ketogenic diet. Report of one case].

    PubMed

    Cornejo, Verónica E; Cabello, Juan Francisco A; Colombo, Marta C; Raimann, Erna B

    2007-05-01

    The glucose transporter type 1 deficiency syndrome (GLUT-1 SD) (OMIM 606777) is an inborn error of metabolism of brain glucose transport. The characteristic clinical manifestations are seizures, hypotonia, developmental delay, microcephaly and hypoglycorrhachia. We report a girl with normal weight and height at birth. At 6 weeks of age she started with convulsions reaching up to 20 myoclonic seizures a day. She was treated with valproate, phenobarbital and carbamazepine without response. Blood analysis including aminoacids and acylcarnitines were all normal. The brain MRI showed frontal atrophy with an increased subarachnoidal space and Electroencephalography was abnormal. Blood glucose was 84 mg/dl and spinal fluid glucose 26 mg/dl with a ratio of 0.31 (Normal Ratio >0.65+/-00.1). These results suggested the diagnosis of GLUT-1 SD, and was confirmed with erythrocyte glucose uptake of 44% (Normal range 80-100%). A molecular study found the mutation 969del, C971T in exon 6 of the gene Glut-1. Treatment with a ketogenic diet was started immediately and after 7 days with this diet seizures ceased. Anticonvulsants were progressively suspended. At present, the patient is 6 years old, she continues on a ketogenic diet and supplements with L-carnitine, lipoic acid, vitamins and minerals. Growth and development are normal with an intelligence quotient of 103. It is concluded that it is necessary to include GLUT-1 SD in the differential diagnosis of children with early seizures that are non responsive to pharmacological treatment.

  6. Using asymmetry analysis to reduce normal variability of Spectral Domain Optical Coherence Tomography (SD-OCT) macular thickness

    NASA Astrophysics Data System (ADS)

    Alluwimi, Muhammed Saad

    Purpose: To investigate the use of asymmetry analysis to reduce normal between-subject variability of macular thickness measurements using SD-OCT. Methods: 63 volunteers free of eye disease were recruited: 33 young subjects (ages 21 to 35 years with mean and SD of 25 +/- 1.7), and 30 older subjects (ages 45 to 85 years with mean and SD of 66.7 +/- 9.0). All participants passed a comprehensive ophthalmic examination within the past two years. Macular images were gathered with the Spectralis OCT (V 5.4, Heidelberg Engineering, GmbH). The overlay 8x8 grid was manually centered on the fovea and aligned with the foveal-disc axis, then divided into five zones per hemifield following the method of Um et al (2012 IOVS 53:1139); asymmetry was computed as the difference between superior and inferior zone thicknesses. We assumed that the lowest variation and the highest density of ganglion cells will be found ~3° to 6° from the foveal center, corresponding to zones 1 and 2. For each zone and age group, between-subject standard deviations (SDs) were compared for retinal thickness (RT) versus asymmetry using an F-test. To account for repeated measures, a probability of p < 0.0125 was required for statistical significance. Axial length (AL) and corneal curvature (CC) were measured with an IOLMaster by the same operator and during the same imaging session. Results: For OD, asymmetry analysis reduced between-subject variability in zones 1 and 2 in both groups (F > 3.2, p < 0.001). SD for zone 1 dropped from 12.0 to 3.0 mum in the young group and from 11.7 to 2.6 mum in the older group. SD for zone 2 dropped from 13.6 to 5.3 mum (young) and from 11.1 to 5.8 mum (older). Combining all subjects, neither RT nor asymmetry showed a strong correlation with AL or CC (R2 < 0.01). Analysis for OS yielded the same pattern of results, as did asymmetry analyses between eyes (F > 3.8, p < 0.0001). Conclusions: Asymmetry analysis reduced between-subject variability. These findings demonstrate

  7. Failure-plane angle in Bentheim sandstone subjected to true triaxial stresses: experimental results and theoretical prediction

    NASA Astrophysics Data System (ADS)

    Ma, Xiaodong; Rudnicki, John; Haimson, Bezalel

    2014-05-01

    We conducted true triaxial tests in the high-porosity (n = 24%), quartz-rich (95%), Bentheim sandstone. An important objective was to investigate the dependence of failure-plane angle θ (angle between the normal to the plane and σ1 direction) on the prevailing stress conditions. We employed two distinct loading paths, and seven σ3 magnitudes (between 0 and 150 MPa). In tests using the common loading path, σ2 and σ3 were fixed, while σ1 was raised monotonically to failure. In tests using the novel loading path (which facilitate comparison with theoretical predictions), σ3 was fixed, and the Lode angle, Θ (= tan-1 [(σ1 - 2σ2 + σ3) / 30.5(σ1 - σ3)]) was kept constant by raising σ1 and σ2 simultaneously at a set ratio b [= (σ2 -σ3)/(σ1 -σ3)] until failure occurred. Six stress ratios b (= 0, 1/6, 1/3, 1/2, 3/4, 1), i.e. six Θ (= tan-1 [(1-2b) / 30.5]) values from +π/6 (axisymmetric compression) to -π/6 (axisymmetric extension) were used. In axisymmetric common loading path tests, failure-plane angle θ generally declined as the applied σ3 = σ2 increased from about 80° at σ3 = σ2 = 0 MPa to 0° at σ3 = σ2 = 150 MPa (forming compaction bands). In tests where σ3 ≠ σ2, the resulting failure-plane strike was consistently parallel to σ2 direction. For low σ3, θ typically rose by up to 12° as σ2 rose from σ2 = σ3 to σ2 = σ1. However, the rise in θ with σ2 tended to diminish at higher σ3. A limiting case occurred at σ3 = 150 MPa, where failure plane remained at 0° , regardless of the rise in σ2. In the novel loading path tests, failure-plane angle θ declined monotonically for any given Lode angle Θ, from roughly 80° to 0° , as the mean stress at failure (σoct,f) rose from about 20 MPa to around 220 MPa; for a constant σoct,f, θ typically increased from 10° (at σoct,f = 20 MPa) to 30° (at σoct,f = 220 MPa) as Θ dropped from +π/6 (σ2 = σ3) to -π/6 (σ2 = σ1). We compared the measured θ with that predicted using

  8. Non extensive statistical physics applied in fracture-induced electric signals during triaxial deformation of Carrara marble

    NASA Astrophysics Data System (ADS)

    Cartwright-Taylor, Alexis; Vallianatos, Filippos; Sammonds, Peter

    2014-05-01

    We have conducted room-temperature, triaxial compression experiments on samples of Carrara marble, recording concurrently acoustic and electric current signals emitted during the deformation process as well as mechanical loading information and ultrasonic wave velocities. Our results reveal that in a dry non-piezoelectric rock under simulated crustal pressure conditions, a measurable electric current (nA) is generated within the stressed sample. The current is detected only in the region beyond (quasi-)linear elastic deformation; i.e. in the region of permanent deformation beyond the yield point of the material and in the presence of microcracking. Our results extend to shallow crustal conditions previous observations of electric current signals in quartz-free rocks undergoing uniaxial deformation and support the idea of a universal electrification mechanism related to deformation. Confining pressure conditions of our slow strain rate (10-6 s-1) experiments range from the purely brittle regime (10 MPa) to the semi-brittle transition (30-100MPa) where cataclastic flow is the dominant deformation mechanism. Electric current is generated under all confining pressures,implying the existence of a current-producing mechanism during both microfracture and frictional sliding. Some differences are seen in the current evolution between these two regimes, possibly related to crack localisation. In all cases, the measured electric current exhibits episodes of strong fluctuations over short timescales; calm periods punctuated by bursts of strong activity. For the analysis, we adopt an entropy-based statistical physics approach (Tsallis, 1988), particularly suited to the study of fracture related phenomena. We find that the probability distribution of normalised electric current fluctuations over short time intervals (0.5 s) can be well described by a q-Gaussian distribution of a form similar to that which describes turbulent flows. This approach yields different entropic

  9. Multiple Sclerosis.

    ERIC Educational Resources Information Center

    Plummer, Nancy; Michael, Nancy, Ed.

    This module on multiple sclerosis is intended for use in inservice or continuing education programs for persons who administer medications in long-term care facilities. Instructor information, including teaching suggestions, and a listing of recommended audiovisual materials and their sources appear first. The module goal and objectives are then…

  10. Experimental Investigation on the Basic Law of the Fracture Spatial Morphology for Water Pressure Blasting in a Drillhole Under True Triaxial Stress

    NASA Astrophysics Data System (ADS)

    Huang, Bingxiang; Li, Pengfeng

    2015-07-01

    The present literature on the morphology of water pressure blasting fractures in drillholes is not sufficient and does not take triaxial confining stress into account. Because the spatial morphology of water pressure blasting fractures in drillholes is not clear, the operations lack an exact basis. Using a large true triaxial water pressure blasting experimental system and an acoustic emission 3-D positioning system, water pressure blasting experiments on cement mortar test blocks (300 mm × 300 mm × 300 mm) were conducted to study the associated basic law of the fracture spatial morphology. The experimental results show that water pressure blasting does not always generate bubble pulsation. After water pressure blasting under true triaxial stress, a crushed compressive zone and a blasting fracture zone are formed from the inside, with the blasting section of the naked drillhole as the center, to the outside. The shape of the outer edges of the two zones is ellipsoidal. The range of the blasting fracture is large in the radial direction of the drillhole, where the surrounding pressure is large, i.e., the range of the blasting fracture in the drillhole radial cross-section is approximately ellipsoidal. The rock near the drillhole wall is affected by a tensile stress wave caused by the test block boundary reflection, resulting in more flake fractures appearing in the fracturing crack surface in the drillhole axial direction and parallel to the boundary surface. The flake fracture is thin, presenting a small-range flake fracture. The spatial morphology of the water pressure blasting fracture in the drillhole along the axial direction is similar to a wide-mouth Chinese bottle: the crack extent is large near the drillhole orifice, gradually narrows inward along the drillhole axial direction, and then increases into an approximate ellipsoid in the internal naked blasting section. Based on the causes of the crack generation, the blasting cracks are divided into three

  11. Prenylated indolediketopiperazine peroxides and related homologues from the marine sediment-derived fungus Penicillium brefeldianum SD-273.

    PubMed

    An, Chun-Yan; Li, Xiao-Ming; Li, Chun-Shun; Xu, Gang-Ming; Wang, Bin-Gui

    2014-02-01

    Three new indolediketopiperazine peroxides, namely, 24-hydroxyverruculogen (1), 26-hydroxyverruculogen (2), and 13-O-prenyl-26-hydroxyverruculogen (3), along with four known homologues (4-7), were isolated and identified from the culture extract of the marine sediment-derived fungus Penicillium brefeldianum SD-273. Their structures were determined based on the extensive spectroscopic analysis and compound 1 was confirmed by X-ray crystallographic analysis. The absolute configuration of compounds 1-3 was determined using chiral HPLC analysis of their acidic hydrolysates. Each of the isolated compounds was evaluated for antibacterial and cytotoxic activity as well as brine shrimp (Artemia salina) lethality. PMID:24473173

  12. [Metabolomic approach to evaluating the effect of the mixed decoction of kelp and licorice on system metabolism of SD rats].

    PubMed

    Sun, Run-bin; Yu, Xiao-yi; Mao, Yong; Ge, Chun; Yang Na; A, Ji-ye; Tang, Yu-ping; Duan, Jin-ao; Ma, Zi-teng; Wu, Xu-tong; Zhu, Xuan-xuan; Wang, Guang-ji

    2015-03-01

    The aim of the study is to evaluate the effects of the single and mixed decoction of Thallus laminariae (kelp) and Glycyrrhiza glabra (licorice) on the metabolism and their difference. The mixed decoction of kelp and licorice and the single decoction were made and intragastrically administered to the SD rats. The effect on system metabolism, the toxicity of liver and kidney were assessed by GC-MS profiling of the endogenous molecules in serum, routine biochemical assays and histographic inspection of tissues from SD rats, separately. The mixed decoction of kelp and licorice induced more obvious pathological abnormalities in SD rats than a single decoction of kelp, while the extracts of licorice did not show any pathological change. Neither the mixed, nor the single decoction showed abnormal histopathology. After intragastric administration of extracts for 5 days, the mixed decoction induced a decrease of ALT (no significant change in the groups of single decoction) and an increase of BUN (so did the single decoction of kelp). Metabolomic profile of the molecules in serum revealed that the metabolic patterns were all obviously affected for the three groups, i.e., the mixed and single decoction of kelp and licorice. The rats given with the single decoction of kelp showed a similar pattern to that of the mixed decoction, indicating that the kelp primarily contributed the perturbation of metabolism for the mixed decoction. All three groups induced a decrease of branched chain amino acids, TCA cycle intermediates and glycolysis intermediates (e.g., pyruvic acid and lactic acid) and an increase of 3-hydroxybutyric acid. Kelp decoction showed stronger potential in reducing TCA cycle intermediates and glycolysis intermediates than the other two groups, while the levels of branched chain amino acids were the lowest after licorice extracts were given. These results suggested that the effect of the mixed decoction on metabolism was closely associated with both kelp and

  13. The NPOESS Preparatory Project Science Data Segment (SDS) Data Depository and Distribution Element (SD3E) System Architecture

    NASA Technical Reports Server (NTRS)

    Ho, Evelyn L.; Schweiss, Robert J.

    2008-01-01

    The National Polar-orbiting Operational Environmental Satellite System (NPOESS) Preparatory Project (NPP) Science Data Segment (SDS) will make daily data requests for approximately six terabytes of NPP science products for each of its six environmental assessment elements from the operational data providers. As a result, issues associated with duplicate data requests, data transfers of large volumes of diverse products, and data transfer failures raised concerns with respect to the network traffic and bandwidth consumption. The NPP SDS Data Depository and Distribution Element (SD3E) was developed to provide a mechanism for efficient data exchange, alleviate duplicate network traffic, and reduce operational costs.

  14. Prenylated Indolediketopiperazine Peroxides and Related Homologues from the Marine Sediment-Derived Fungus Penicillium brefeldianum SD-273

    PubMed Central

    An, Chun-Yan; Li, Xiao-Ming; Li, Chun-Shun; Xu, Gang-Ming; Wang, Bin-Gui

    2014-01-01

    Three new indolediketopiperazine peroxides, namely, 24-hydroxyverruculogen (1), 26-hydroxyverruculogen (2), and 13-O-prenyl-26-hydroxyverruculogen (3), along with four known homologues (4–7), were isolated and identified from the culture extract of the marine sediment-derived fungus Penicillium brefeldianum SD-273. Their structures were determined based on the extensive spectroscopic analysis and compound 1 was confirmed by X-ray crystallographic analysis. The absolute configuration of compounds 1–3 was determined using chiral HPLC analysis of their acidic hydrolysates. Each of the isolated compounds was evaluated for antibacterial and cytotoxic activity as well as brine shrimp (Artemia salina) lethality. PMID:24473173

  15. Myeloma (multiple)

    PubMed Central

    2006-01-01

    Introduction Multiple myeloma is the most common primary cancer of the bones in adults, representing about 1% of all cancers diagnosed in the US in 2004, and 14% of all haematological malignancies. In the UK, multiple myeloma accounts for 1% of all new cases of cancer diagnosed each year. Methods and outcomes We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of treatment in people with asymptomatic early stage multiple myeloma (stage I)? What are the effects of first-line treatments in people with advanced stage multiple myeloma (stages II and III)? What are the effect of salvage treatments, or supportive therapy, in people with advanced stage multiple myeloma (stages II and III)? We searched: Medline, Embase, The Cochrane Library and other important databases up to November 2004 (Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). Results We found 71 systematic reviews, RCTs, or observational studies that met our inclusion criteria. Conclusions In this systematic review we present information relating to the effectiveness and safety of the following interventions: allogenic transplant (non-myeloablative), autologous stem cell transplant (early or late transplantation, double or single, purging of), bisphosphonates, bone marrow stem cells, bortezomib, chemotherapy (combination, conventional dose, intermediate dose plus stem cell rescue, high-dose plus stem cell rescue), combination chemotherapy plus corticosteroids, deferred treatment (in stage I disease), early chemotherapy plus corticosteroids (in stage I disease), epoetin alpha, first-line treatments, infection prophylaxis, interferon, maintenance therapy (in advanced multiple myeloma), melphalan (normal dose

  16. Chiral geometry in multiple chiral doublet bands

    NASA Astrophysics Data System (ADS)

    Zhang, Hao; Chen, Qibo

    2016-02-01

    The chiral geometry of multiple chiral doublet bands with identical configuration is discussed for different triaxial deformation parameters γ in the particle rotor model with . The energy spectra, electromagnetic transition probabilities B(M1) and B(E2), angular momenta, and K-distributions are studied. It is demonstrated that the chirality still remains not only in the yrast and yrare bands, but also in the two higher excited bands when γ deviates from 30°. The chiral geometry relies significantly on γ, and the chiral geometry of the two higher excited partner bands is not as good as that of the yrast and yrare doublet bands. Supported by Plan Project of Beijing College Students’ Scientific Research and Entrepreneurial Action, Major State 973 Program of China (2013CB834400), National Natural Science Foundation of China (11175002, 11335002, 11375015, 11461141002), National Fund for Fostering Talents of Basic Science (NFFTBS) (J1103206), Research Fund for Doctoral Program of Higher Education (20110001110087) and China Postdoctoral Science Foundation (2015M580007)

  17. Time dependence of mesoscopic strain distribution for triaxial woven carbon-fiber-reinforced polymer under creep loading measured by digital image correlation

    NASA Astrophysics Data System (ADS)

    Koyanagi, Jun; Nagayama, Hideo; Yoneyama, Satoru; Aoki, Takahira

    2016-06-01

    This paper presents the time dependence of the mesoscopic strain of a triaxial woven carbon-fiber-reinforced polymer under creep loading measured using digital image correlation (DIC). Two types of DIC techniques were employed for the measurement: conventional subset DIC and mesh DIC. Static tensile and creep tests were carried out, and the time dependence of the mesoscopic strain distribution was investigated by applying these techniques. The ultimate failure of this material is dominated by inter-bundle decohesion caused by relative rigid rotation and relating shear stress. Therefore, these were focused on in the present study. During the creep tests, the fiber directional strain, shear strain, and rotation were monitored using the DIC, and the mechanism for the increase in the specimen's macro-strain over time was investigated based on the results obtained by the DIC measurement.

  18. High-spin states in {sup 191,193}Au and {sup 192}Pt: Evidence for oblate deformation and triaxial shapes

    SciTech Connect

    Oktem, Y.; Akkus, B.; Bostan, M.; Cakirli, R. B.; Erduran, M. N.; Balabanski, D. L.; Beausang, C. W.; Casten, R. F.; Kruecken, R.; Novak, J. R.; Danchev, M.; Djongolov, M.; Riedinger, L. L.; Zeidan, O.; Erturk, S.; Gladniski, K. A.; Rainovski, G.; Guerdal, G.; Goon, J. Tm.; Hartley, D. J.

    2007-10-15

    High-spin states of {sup 191,193}Au and {sup 192}Pt have been populated in the {sup 186}W({sup 11}B, xn) and {sup 186}W({sup 11}B, p4n) reactions, respectively, at a beam energy of 68 MeV and their {gamma} decay was studied using the YRAST Ball detector array at the Wright Nuclear Structure Laboratory at Yale University. The level scheme of {sup 193}Au has been extended up to I{sup {pi}}=55/2{sup +}. New transitions were observed also in {sup 191}Au and {sup 192}Pt. Particle-plus-Triaxial-Rotor (PTR) and Total Routhian Surface (TRS) calculations were performed to determine the equilibrium deformations of the Au isotopes. The predictions for oblate deformations in these nuclei are in agreement with the experimental data. Development of nonaxial shapes is discussed within the framework of the PTR model.

  19. Neutron stress measurement of triaxial residual stress tensors in an aerospace weldment before and after post-weld heat-treatment

    SciTech Connect

    Winholtz, R.A.; Krawitz, A.D.

    1996-12-31

    Triaxial stress tensors and their corresponding principal stresses were determined with neutron diffraction, before and after post-weld heat-treatment, at 14 positions in and near a circumferential weld in a subscale model cylinder of the NASA-Advanced Solid Rocket Motor. No principal stress directions were assumed in making the measurements. The principal stresses range from {minus}393 to +1,045 MPa in the as-welded condition and decreased to a range of {minus}212 to +421 MPa after post-weld heat-treatment. The largest as-welded tensile stresses were located around the cap pass heat affected zone in the interior of the material and were aligned with the hoop direction of the cylinder.

  20. A phoenics model for the triaxial loading of an initially cylindrical mass of rate-type material with provisions for bulging and yield

    NASA Technical Reports Server (NTRS)

    French, K. W., Jr.

    1986-01-01

    This work traces the response of a granular material via the Ten Coefficient Truesdell rate-type constituitive model into the simplest meaningful loading: the triaxial test configuration. A functional relation has been posed for computing the rather peculiar relation between average applied stress and average porosity. Using that relation an attack has been mounted on the dilemma that exists between dynamic and constitutive use of the pressure variable; that is relating dynamic pressure, thermodynamic pressure, stress deviator and higher stress invariants. The resolution was as a linear superposition with a one-way feedback, in that while the dynamic component could not effect the constituitive component, the converse was not true since density appears in the momentum transport relation.

  1. Care Partners and Multiple Sclerosis

    PubMed Central

    Quig, Mary Elizabeth; Tyry, Tuula; Marrie, Ruth Ann; Cutter, Gary; Shearin, Edward; Johnson, Kamau; Simsarian, James

    2015-01-01

    Background: Caring for someone with multiple sclerosis (MS) can be a stressful experience that requires clinical attention. We investigated the impact of caregiver stress on the emotional well-being and physical health of the MS care partner using the North American Research Committee on Multiple Sclerosis (NARCOMS) Registry. Methods: Care partners of NARCOMS participants were invited to complete an online questionnaire that captured demographic characteristics, health status, caregiver burden as measured by the Zarit Caregiver Burden Interview, and impact of caregiving on employment. Results: Of 1446 care partners who agreed to participate, 1333 had complete data. Most were men (n = 825, 61.9%), with a mean (SD) age of 51.1 (11.2) years. The mean (SD) Zarit total score was 24.6 (15.1), placing the overall group in the mild caregiver burden range. Compared with male care partners, female care partners reported higher levels of burden and stress and more medication use for stress/anxiety and mood disorders. Male care partners were more likely to report physical concerns. Care partners of people with primary progressive MS reported greater perceived burden than did partners of people with secondary progressive MS and relapsing-remitting MS. More than 40% of care partners (559 of 1288) had missed work during the past year owing to caregiving responsibilities. Conclusions: Care partners of people with MS have substantial physical and psychological health concerns and experience an adverse impact on employment. Future research should evaluate how to mitigate the adverse effects of caregiving and evaluate positive aspects of the role. PMID:26664330

  2. Concurrent validity of accelerations measured using a tri-axial inertial measurement unit while walking on firm, compliant and uneven surfaces.

    PubMed

    Cole, Michael H; van den Hoorn, Wolbert; Kavanagh, Justin K; Morrison, Steven; Hodges, Paul W; Smeathers, James E; Kerr, Graham K

    2014-01-01

    Although accelerometers are extensively used for assessing gait, limited research has evaluated the concurrent validity of these devices on less predictable walking surfaces or the comparability of different methods used for gravitational acceleration compensation. This study evaluated the concurrent validity of trunk accelerations derived from a tri-axial inertial measurement unit while walking on firm, compliant and uneven surfaces and contrasted two methods used to remove gravitational accelerations; i) subtraction of the best linear fit from the data (detrending); and ii) use of orientation information (quaternions) from the inertial measurement unit. Twelve older and twelve younger adults walked at their preferred speed along firm, compliant and uneven walkways. Accelerations were evaluated for the thoracic spine (T12) using a tri-axial inertial measurement unit and an eleven-camera Vicon system. The findings demonstrated excellent agreement between accelerations derived from the inertial measurement unit and motion analysis system, including while walking on uneven surfaces that better approximate a real-world setting (all differences <0.16 m.s(-2)). Detrending produced slightly better agreement between the inertial measurement unit and Vicon system on firm surfaces (delta range: -0.05 to 0.06 vs. 0.00 to 0.14 m.s(-2)), whereas the quaternion method performed better when walking on compliant and uneven walkways (delta range: -0.16 to -0.02 vs. -0.07 to 0.07 m.s(-2)). The technique used to compensate for gravitational accelerations requires consideration in future research, particularly when walking on compliant and uneven surfaces. These findings demonstrate trunk accelerations can be accurately measured using a wireless inertial measurement unit and are appropriate for research that evaluates healthy populations in complex environments.

  3. Concurrent Validity of Accelerations Measured Using a Tri-Axial Inertial Measurement Unit while Walking on Firm, Compliant and Uneven Surfaces

    PubMed Central

    Cole, Michael H.; van den Hoorn, Wolbert; Kavanagh, Justin K.; Morrison, Steven; Hodges, Paul W.; Smeathers, James E.; Kerr, Graham K.

    2014-01-01

    Although accelerometers are extensively used for assessing gait, limited research has evaluated the concurrent validity of these devices on less predictable walking surfaces or the comparability of different methods used for gravitational acceleration compensation. This study evaluated the concurrent validity of trunk accelerations derived from a tri-axial inertial measurement unit while walking on firm, compliant and uneven surfaces and contrasted two methods used to remove gravitational accelerations; i) subtraction of the best linear fit from the data (detrending); and ii) use of orientation information (quaternions) from the inertial measurement unit. Twelve older and twelve younger adults walked at their preferred speed along firm, compliant and uneven walkways. Accelerations were evaluated for the thoracic spine (T12) using a tri-axial inertial measurement unit and an eleven-camera Vicon system. The findings demonstrated excellent agreement between accelerations derived from the inertial measurement unit and motion analysis system, including while walking on uneven surfaces that better approximate a real-world setting (all differences <0.16 m.s−2). Detrending produced slightly better agreement between the inertial measurement unit and Vicon system on firm surfaces (delta range: −0.05 to 0.06 vs. 0.00 to 0.14 m.s−2), whereas the quaternion method performed better when walking on compliant and uneven walkways (delta range: −0.16 to −0.02 vs. −0.07 to 0.07 m.s−2). The technique used to compensate for gravitational accelerations requires consideration in future research, particularly when walking on compliant and uneven surfaces. These findings demonstrate trunk accelerations can be accurately measured using a wireless inertial measurement unit and are appropriate for research that evaluates healthy populations in complex environments. PMID:24866262

  4. Concurrent validity of accelerations measured using a tri-axial inertial measurement unit while walking on firm, compliant and uneven surfaces.

    PubMed

    Cole, Michael H; van den Hoorn, Wolbert; Kavanagh, Justin K; Morrison, Steven; Hodges, Paul W; Smeathers, James E; Kerr, Graham K

    2014-01-01

    Although accelerometers are extensively used for assessing gait, limited research has evaluated the concurrent validity of these devices on less predictable walking surfaces or the comparability of different methods used for gravitational acceleration compensation. This study evaluated the concurrent validity of trunk accelerations derived from a tri-axial inertial measurement unit while walking on firm, compliant and uneven surfaces and contrasted two methods used to remove gravitational accelerations; i) subtraction of the best linear fit from the data (detrending); and ii) use of orientation information (quaternions) from the inertial measurement unit. Twelve older and twelve younger adults walked at their preferred speed along firm, compliant and uneven walkways. Accelerations were evaluated for the thoracic spine (T12) using a tri-axial inertial measurement unit and an eleven-camera Vicon system. The findings demonstrated excellent agreement between accelerations derived from the inertial measurement unit and motion analysis system, including while walking on uneven surfaces that better approximate a real-world setting (all differences <0.16 m.s(-2)). Detrending produced slightly better agreement between the inertial measurement unit and Vicon system on firm surfaces (delta range: -0.05 to 0.06 vs. 0.00 to 0.14 m.s(-2)), whereas the quaternion method performed better when walking on compliant and uneven walkways (delta range: -0.16 to -0.02 vs. -0.07 to 0.07 m.s(-2)). The technique used to compensate for gravitational accelerations requires consideration in future research, particularly when walking on compliant and uneven surfaces. These findings demonstrate trunk accelerations can be accurately measured using a wireless inertial measurement unit and are appropriate for research that evaluates healthy populations in complex environments. PMID:24866262

  5. High-resolution spectrometer: solution to the axial resolution and ranging depth trade-off of SD-OCT

    NASA Astrophysics Data System (ADS)

    Marvdashti, Tahereh; Lee, Hee Yoon; Ellerbee, Audrey K.

    2013-03-01

    We demonstrate a cross-dispersed spectrometer for Spectral Domain Optical Coherence Tomography (SD-OCT). The resolution of a conventional SD-OCT spectrometer is limited by the available sizes of the linear array detectors. The adverse consequences of this finite resolution is a trade-off between achieving practical field of view (i.e. ranging depth) and maintaining high axial resolution. Inspired by spectrometer designs for astronomy, we take advantage of very high pixel-density 2D CCD arrays to map a single-shot 2D spectrum to an OCT A-scan. The basic system can be implemented using a high-resolution Echelle grating crossed with a prism in a direction orthogonal to the dispersion axis. In this geometry, the interferometric light returning from the OCT system is dispersed in two dimensions; the resulting spectrum can achieve more pixels than a traditional OCT spectrometer (which increases the ranging depth) and maintains impressive axial resolution because of the broad bandwidth of the detected OCT light. To the best of our knowledge, we present the first demonstration of OCT data using an Echelle-based cross-dispersed spectrometer. Potential applications for such a system include high-resolution imaging of the retina or the anterior segment of the eye over extended imaging depths and small animal imaging.

  6. Pattern of inner retinal layers involvement in pigmented paravenous retinochoroidal atrophy as determined by SD-OCT: case report.

    PubMed

    Junqueira, Daniela Laura Melo; Lopes, Flavio Siqueira Santos; Biteli, Luís Gustavo; Prata, Tiago Santos

    2013-01-01

    Pigmented paravenous retinochoroidal atrophy is an ocular disease characterized by outer retina and choroidal atrophy often with overlying intraretinal bone spicule pigment deposition along the retinal veins. As a rare condition, there is scant information in the literature regarding the pattern of inner retinal layers involvement. We present a case of a 41-year-old white man initially referred for a glaucoma evaluation. Fundoscopy revealed patches of retinochoroidal atrophy and light pigmentation extending from the optic nerve head along the inferior-temporal retinal veins in both eyes. Using different spectral-domain optical coherence tomography (SD-OCT) protocols we identified a significant thinning of the inner retinal layers along the inferior-temporal veins, but with a lucid interval surrounding the optic nerve head. Standard automated perimetry revealed a superior absolute arcuate scotoma sparing the central fixation (good structure-functional correlation). This pattern of inner retinal layers involvement was not previously described. We believe SD-OCT added significantly to the anatomical description of this case. Physicians should consider these new anatomical findings and correlate them with functional status while assessing these patients.

  7. The physical structure of planetary nebulae around sdO stars: Abell 36, DeHt 2, and RWT 152

    NASA Astrophysics Data System (ADS)

    Aller, A.; Miranda, L. F.; Olguín, L.; Vázquez, R.; Guillén, P. F.; Oreiro, R.; Ulla, A.; Solano, E.

    2015-01-01

    We present narrow-band Hα and [O III] images, and high-resolution, long-slit spectra of the planetary nebulae (PNe) Abell 36, DeHt 2, and RWT 152 aimed at studying their morphology and internal kinematics. These data are complemented with intermediate-resolution, long-slit spectra to describe the spectral properties of the central stars and nebulae. The morphokinematical analysis shows that Abell 36 consists of an inner spheroid and two bright point-symmetric arcs; DeHt 2 is elliptical with protruding polar regions and a bright non-equatorial ring; and RWT 152 is bipolar. The formation of Abell 36 and DeHt 2 requires several ejection events including collimated bipolar outflows that probably are younger than and have disrupted the main shell. The nebular spectra of the three PNe show a high excitation and also suggest a possible deficiency in heavy elements in DeHt 2 and RWT 152. The spectra of the central stars strongly suggest an sdO nature and their association with PNe points out that they have most probably evolved through the asymptotic giant branch. We analyse general properties of the few known sdOs associated with PNe and find that most of them are relatively or very evolved PNe, show complex morphologies, host binary central stars, and are located at relatively high Galactic latitudes.

  8. Multiple Sclerosis

    PubMed Central

    2013-01-01

    Multiple sclerosis (MS) is a chronic progressive demyelinating disease of the central nervous system. Common manifestations include paresthesias, diplopia, loss of vision, numbness or weakness of the limbs, bowel or bladder dysfunction, spasticity, ataxia, fatigue, and mental changes. Four main patterns of MS are recognized: relapsing remitting, primary progressive, secondary progressive, and progressive relapsing. The cause of MS is unknown, although it appears to be an autoimmune disease. Much of what is known about MS has been learned from an animal model of the disease, experimental allergic encephalomyelitis. PMID:24381825

  9. Multiple Sclerosis.

    PubMed

    Schiess, Nicoline; Calabresi, Peter A

    2016-08-01

    It is estimated that there are 300,000 people with multiple sclerosis (MS) in the United States and 2.3 million worldwide. Each MS attack can affect function in cognitive, emotional, motoric, sensory, or visual domains. Patients are often struck in the prime of their lives as they attempt to move forward with career, and family. Since the previous 2010 Seminars in Neurology Pearls and Pitfalls issue, the world of MS has drastically changed and advanced. Here the authors address the ever-changing MS world in both treatment options and diagnostics, covering easily missed differential diagnoses, newly available immunomodulatory therapy, and the challenges of safely treating patients. PMID:27643903

  10. Multiple myeloma

    PubMed Central

    Rajkumar, S. Vincent

    2008-01-01

    Multiple myeloma is a clonal plasma cell malignancy that accounts for slightly more than 10% of all hematologic cancers. In this paper, we present a historically focused review of the disease, from the description of the first case in 1844 to the present. The evolution of drug therapy and stem-cell transplantation for the treatment of myeloma, as well as the development of new agents, is discussed. We also provide an update on current concepts of diagnosis and therapy, with an emphasis on how treatments have emerged from a historical perspective after certain important discoveries and the results of experimental studies. PMID:18332230

  11. [Multiple myeloma].

    PubMed

    Abe, Masahiro; Miki, Hirokazu; Nakamura, Shingen

    2016-03-01

    Owing to the positive clinical benefits obtained with new agents, complete remission (CR) can be used as a surrogate for overall survival, and should be achieved. Although multiple myeloma is a heterogeneous disease in terms of myeloma cell- and patient-related risk factors, patients should receive the most effective combination therapy based on proteasome inhibitors and/or immunomodulatory drugs (IMiDs) as backbone medication irrespective of the risks encountered in the setting of induction therapy ("one-size-fits-all" therapy), followed by consolidation/maintenance therapy to achieve CR with the ultimate goal of extended survival. Myeloma-defining biomarkers have been established to identify high-risk smoldering myeloma requiring treatment. The development of salvage treatments yielding better outcomes for relapsed/refractory myeloma is urgently needed. Upcoming novel molecular targeting agents with different modes of action and immunotherapeutic agents will be integrated into myeloma treatment regimens with a great therapeutic impact, and further evolution of the treatment paradigm for multiple myeloma is eagerly anticipated. PMID:27076236

  12. Activation of c-myb by 5' retrovirus promoter insertion in myeloid neoplasms is dependent upon an intact alternative splice donor site (SD') in gag

    SciTech Connect

    Ramirez, Jean Marie; Houzet, Laurent; Koller, Richard; Bies, Juraj; Wolff, Linda; Mougel, Marylene . E-mail: mmougel@univ-montp1.fr

    2004-12-20

    Alternative splicing in Mo-MuLV recruits a splice donor site, SD', within the gag that is required for optimal replication in vitro. Remarkably, this SD' site was also found to be utilized for production of oncogenic gag-myb fusion RNA in 100% of murine-induced myeloid leukemia (MML) in pristane-treated BALB/c mice. Therefore, we investigated the influence of silent mutations of SD' in this model. Although there was no decrease in the overall incidence of disease, there was a decrease in the incidence of myeloid leukemia with a concomitant increase in lymphoid leukemia. Importantly, there was a complete lack of myeloid tumors associated with 5' insertional mutagenic activation of c-myb, suggesting the specific requirement of the SD' site in this mechanism.

  13. Continuous imaging of the blood vessels in tumor mouse dorsal skin window chamber model by using SD-OCT

    NASA Astrophysics Data System (ADS)

    Peng, Xiao; Yang, Shaozhuang; Yu, Bin; Wang, Qi; Lin, Danying; Gao, Jian; Zhang, Peiqi; Ma, Yiqun; Qu, Junle; Niu, Hanben

    2016-03-01

    Optical Coherence Tomography (OCT) has been widely applied into microstructure imaging of tissues or blood vessels with a series of advantages, including non-destructiveness, real-time imaging, high resolution and high sensitivity. In this study, a Spectral Domain OCT (SD-OCT) system with higher sensitivity and signal-to-noise ratio (SNR) was built up, which was used to observe the blood vessel distribution and blood flow in the dorsal skin window chamber of the nude mouse tumor model. In order to obtain comparable data, the distribution images of blood vessels were collected from the same mouse before and after tumor injection. In conclusion, in vivo blood vessel distribution images of the tumor mouse model have been continuously obtained during around two weeks.

  14. Theoretical study of structure and production of F19Λ as a gateway to sd-shell hypernuclei

    NASA Astrophysics Data System (ADS)

    Umeya, Atsushi; Motoba, Toshio

    2016-10-01

    Energy level structures of the typical light sd-shell hypernucleus F19Λ, together with 18F, have been studied in detail with the multi-configuration shell model. Both positive-parity and negative-parity nuclear core excitations are fully taken into account by removing the spurious center-of-mass excitation effects. Corresponding to the J-PARC proposal of the 19F (K- ,π- γ) F19Λ experiment, the production cross sections have been estimated extensively, including the angular distributions. Starting with the elementary amplitudes for the K- n → Λπ- process, the microscopic DWIA calculations at high energy kaon momenta up to 1.8 GeV / c have been carried out for the first time. The calculated wave functions are also used to estimate the electromagnetic transition probabilities for both 18F and F19Λ. The detailed γ-decay schemes are presented and discussed.

  15. Chemical profile of the secondary metabolites produced by a deep-sea sediment-derived fungus Penicillium commune SD-118

    NASA Astrophysics Data System (ADS)

    Shang, Zhuo; Li, Xiaoming; Meng, Li; Li, Chunshun; Gao, Shushan; Huang, Caiguo; Wang, Bingui

    2012-03-01

    Bioassay-guided fractionation of the crude extract from Penicillium commune SD-118, a fungus obtained from a deep-sea sediment sample, resulted in the isolation of a known antibacterial compound, xanthocillin X ( 1), and 14 other known compounds comprising three steroids ( 2-4), two ceramides ( 5 and 6), six aromatic compounds ( 7-12), and three alkaloids ( 13-15). Xanthocillin X ( 1) was isolated for the first time from a marine fungus. In the bioassay, xanthocillin X ( 1) displayed remarkable antimicrobial activity against Staphylococcus aureus and Escherichia coli, and significant cytotoxicity against MCF-7, HepG2, H460, Hela, Du145, and MDA-MB-231 cell lines. Meleagrin ( 15) exhibited cytotoxicity against HepG2, Hela, Du145, and MDA-MB-231 cell lines. This is the first report of the cytotoxicity of xanthocillin X ( 1).

  16. Analysis of Genes for Succinoyl Trehalose Lipid Production and Increasing Production in Rhodococcus sp. Strain SD-74

    PubMed Central

    Inaba, Tomohiro; Tokumoto, Yuta; Miyazaki, Yusuke; Inoue, Naoyuki; Maseda, Hideaki; Nakajima-Kambe, Toshiaki; Uchiyama, Hiroo

    2013-01-01

    Succinoyl trehalose lipids (STLs) are promising glycolipid biosurfactants produced from n-alkanes that are secreted by Rhodococcus species bacteria. These compounds not only exhibit unique interfacial properties but also demonstrate versatile biochemical actions. In this study, three novel types of genes involved in the biosynthesis of STLs, including a putative acyl coenzyme A (acyl-CoA) transferase (tlsA), fructose-bisphosphate aldolase (fda), and alkane monooxygenase (alkB), were identified. The predicted functions of these genes indicate that alkane metabolism, sugar synthesis, and the addition of acyl groups are important for the biosynthesis of STLs. Based on these results, we propose a biosynthesis pathway for STLs from alkanes in Rhodococcus sp. strain SD-74. By overexpressing tlsA, we achieved a 2-fold increase in the production of STLs. This study advances our understanding of bacterial glycolipid production in Rhodococcus species. PMID:24038682

  17. Toxic Effects of Tetrabromobisphenol A on Thyroid Hormones in SD Rats and the Derived-reference Dose.

    PubMed

    Yang, Yan; Ni, Wei Wei; Yu, Lin; Cai, Ze; Yu, Yun Jiang

    2016-04-01

    The present study determined the thyroid hormone interference of tetrabromobisphenol A (TBBPA) in Sprague-Dawley (SD) rats, and the derived-reference dose (RfD) of different endpoint effects on mammals based on experimental results and data collection. Based on repeated exposure toxicity tests on mammals and extensive research, the present study used BMDS240 Software to derive a benchmark dose, and analyzed the accuracy and uncertainty, and similarity with other studies. Test results on triiodothyronine (T3), thyroxine (T4), and thyroid stimulating hormone (TSH) demonstrated that all the indicators presented a non-monotonous dose-effect relationship clearly, except TSH in male rats exposed to 0-1000 mg/kg BW per day. Therefore, RfDs were derived from different critical effects. In summary, RfD for mammals in the present study was found to be 0.6 mg/kg per day. PMID:27241741

  18. Supercontinuum generation in nonlinear fibers using high-energy figure-of-eight mode-locked fiber laser for SD-OCT application

    NASA Astrophysics Data System (ADS)

    Xu, Bo; Nagata, Tsubasa; Yamashita, Shinji

    2014-05-01

    Generation of flat and broadband supercontinum is demonstrated in an all fiber system using the high-energy noise-like pulses from a stable figure-of-eight fiber laser and nonlinear fibers. This SC source is successfully applied to the spectral domain optical coherence tomography (SD-OCT). The axial resolution is significantly improved compared with the case of the superluminescent diode source. SD-OCT imaging is also demonstrated.

  19. Expression and purification of a single-chain Type IV restriction enzyme Eco94GmrSD and determination of its substrate preference.

    PubMed

    He, Xinyi; Hull, Victoria; Thomas, Julie A; Fu, Xiaoqing; Gidwani, Sonal; Gupta, Yogesh K; Black, Lindsay W; Xu, Shuang-yong

    2015-05-19

    The first reported Type IV restriction endonuclease (REase) GmrSD consists of GmrS and GmrD subunits. In most bacteria, however, the gmrS and gmrD genes are fused together to encode a single-chain protein. The fused coding sequence for ECSTEC94C_1402 from E. coli strain STEC_94C was expressed in T7 Express. The protein designated as Eco94GmrSD displays modification-dependent ATP-stimulated REase activity on T4 DNA with glucosyl-5-hydroxymethyl-cytosines (glc-5hmC) and T4gt DNA with 5-hydroxymethyl-cytosines (5hmC). A C-terminal 6xHis-tagged protein was purified by two-column chromatography. The enzyme is active in Mg(2+) and Mn(2+) buffer. It prefers to cleave large glc-5hmC- or 5hmC-modified DNA. In phage restriction assays, Eco94GmrSD weakly restricted T4 and T4gt, whereas T4 IPI*-deficient phage (Δip1) were restricted more than 10(6)-fold, consistent with IPI* protection of E. coli DH10B from lethal expression of the closely homologous E. coli CT596 GmrSD. Eco94GmrSD is proposed to belong to the His-Asn-His (HNH)-nuclease family by the identification of a putative C-terminal REase catalytic site D507-H508-N522. Supporting this, GmrSD variants D507A, H508A, and N522A displayed no endonuclease activity. The presence of a large number of fused GmrSD homologs suggests that GmrSD is an effective phage exclusion protein that provides a mechanism to thwart T-even phage infection.

  20. Complete Genome Sequence of Herbinix luporum SD1D, a New Cellulose-Degrading Bacterium Isolated from a Thermophilic Biogas Reactor

    PubMed Central

    Koeck, Daniela E.; Maus, Irena; Wibberg, Daniel; Winkler, Anika; Zverlov, Vladimir V.; Liebl, Wolfgang; Pühler, Alfred; Schwarz, Wolfgang H.

    2016-01-01

    A novel cellulolytic bacterial strain was isolated from an industrial-scale biogas plant. The 16S rRNA gene sequence of the strain SD1D showed 96.4% similarity to Herbinix hemicellulosilytica T3/55T, indicating a novel species within the genus Herbinix (family Lachnospiraceae). Here, the complete genome sequence of Herbinix luporum SD1D is reported. PMID:27445379