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Sample records for parameter pair m3

  1. Hot HB Stars in Globular Clusters: Physical Parameters and Consequences for Theory. VI; The Second Parameter Pair M 3 and M 13

    NASA Technical Reports Server (NTRS)

    Moehler, S.; Landsman, W. B.; Sweigart, A. V.; Grundahl, F.

    2003-01-01

    We present the results of spectroscopic analyses of hot horizontal branch (HB) stars in M 13 and M 3, which form a famous "second parameter" pair. F rom the spectra and Stromgren photometry we derived - for the first time in M 13 - atmospheric parameters (effective temperature and surface gravity). For stars with Stromgren temperatures between 10,000 and 12,000 K we found excellent agreement between the atmospheric parameters derived from Stromgren photometry and those derived from Balmer line profile fits. However, for cooler stars there is a disagreement in the parameters derived by the two methods, for which we have no satisfactory explanation. Stars hotter than 12,000 K show evidence for helium depletion and iron enrichment, both in M 3 and M 13. Accounting for the iron enrichment substantially improves the agreement with canonical evolutionary models, although the derived gravities and masses are still somewhat too low. This remaining discrepancy may be an indication that scaled-solar metal-rich model atmospheres do not adequately represent the highly non-solar abundance ratios found in blue HB stars affected by diffusion. We discuss the effects of an enhancement in the envelope helium abundance on the atmospheric parameters of the blue HB stars, as might be caused by deep mixing on the red giant branch or primordial pollution from an earlier generation of intermediate mass asymptotic giant branch stars. Key words. Stars: atmospheres - Stars: evolution - Stars: horizontal branch - Globular clusters: individual: M 3 - Globular clusters: individual: M 13

  2. Hot HB Stars in Globular Clusters - Physical Parameters and Consequences for Theory. VI. The Second Parameter Pair M3 and M13

    NASA Technical Reports Server (NTRS)

    Moehler, S.; Landsman, W. B.; Sweigart, A. V.; Grundahl, F.

    2002-01-01

    We present the results of spectroscopic analyses of hot horizontal branch (HB) stars in M13 and M3, which form a famous second parameter pair. From the spectra we derived - for the first time in M13 - atmospheric parameters (effective temperature and surface gravity) as well as abundances of helium, magnesium, and iron. Consistent with analyses of hot HB stars in other globular clusters we find evidence for helium depletion and iron enrichment in stars hotter than about 12,000 K in both M3 and M13. Accounting for the iron enrichment substantially improves the agreement with canonical evolutionary models, although the derived gravities and masses are still somewhat too low. This remaining discrepancy may be an indication that scaled-solar metal-rich model atmospheres do not adequately represent the highly non-solar abundance ratios found in blue HB stars with radiative levitation. We discuss the effects of an enhancement in the envelope helium abundance on the atmospheric parameters of the blue HB stars, as might be caused by deep mixing on the red giant branch or primordial pollution from an earlier generation of intermediate mass asymptotic giant branch stars.

  3. Geometrical parameters of E+S pairs

    NASA Technical Reports Server (NTRS)

    Rampazzo, Roberto; Sulentic, Jack W.

    1990-01-01

    Local environmental conditions (i.e., density and angular momentum properties of protogalactic clouds) are thought to be factors affecting the ultimate morphology of a galaxy. The existence of significant numbers of mixed morphology (E/SO+S) pairs of galaxies would represent a direct challenge to this idea unless all early-type components are formed by mergers. The authors wished to isolate candidate E+S pairs for detailed study. The authors have observed 22 pairs of mixed morphology galaxies (containing at least one early-type component) selected from a catalog of Sulentic (1988: unpublished) based upon the ESO sky survey. The observed sample and relevant morphological and interaction characteristics are summarized in tabular form. The authors report the relevant geometrical properties of the galaxies in another table. They list the maximum values measured for the ellipticity and the a(4)/a shape parameter together with the total measured twisting along the profile beyond the seeing disk (they set an inner limit of 3 arcsed). An asterisk indicates objects in which a(4)/a is neither predominantly boxy nor disky. They found a large number of true mixed pairs with 13/22 E+S pairs in the present sample. The remaining objects include 5 disk pairs (composed of SO and S members) and 3 early-type pairs comprising E and SO members. They estimate that between 25 and 50 percent of the pairs in any complete sample will be of the E+S type. This suggests that 100 to 200 such pairs exist on the sky brighter than m sub pg = 16.0. They found no global evidence for a difference between E members of this sample and those in more general samples (e.g., Bender et al. 1989). In particular, they found that about 30 percent of the early-type galaxies cannot be classified either predominantly boxy or disky because the a(4)/a profile shows both of these features at a comparable level or does not show any significant trend. Isophotal twisting is observed with a range and distribution

  4. Possibilities of paired comparison of receptor binding parameters obtained in a single experiment

    SciTech Connect

    Mashilova, K.V.; Kiriakov, G.V.; Malin, K.M.; Rozhanets, V.V.

    1987-09-01

    The authors explore the use of comparing control and experimental groups on the basis of extrapolation parameters obtained from a single pair of experiments. One of the experiments study the parameters of specific binding of /sup 3/H-D-ala-2-enkephelin-5-D-leucine in the striatum of different groups of rats. The analysis was done by the Cornish-Bowden method.

  5. Finite Momentum Pairing and Spatially Varying Order Parameter in Proximitized HgTe Quantum Wells

    NASA Astrophysics Data System (ADS)

    Yacoby, Amir

    Conventional s-wave superconductivity is understood to arise from singlet pairing of electrons with opposite Fermi momenta, forming Cooper pairs whose net momentum is zero. Several recent studies have focused on structures where such conventional s-wave superconductors are coupled to systems with an unusual configuration of electronic spin and momentum at the Fermi surface. Under these conditions, the nature of the paired state can be modified and the system may even undergo a topological phase transition. Here we present measurements and theoretical calculations of several HgTe quantum wells coupled to either aluminum or niobium superconductors and subject to a magnetic field in the plane of the quantum well. By studying the oscillatory response of Josephson interference to the magnitude of the in-plane magnetic field, we find that the induced pairing within the quantum well oscillates between singlet and triplet pairing and is spatially varying. Cooper pairs acquire a tunable momentum that grows with magnetic field strength, directly reflecting the response of the spin-dependent Fermi surfaces to the in-plane magnetic field. Our new understanding of the interplay between spin physics and superconductivity introduces a way to spatially engineer the order parameter, as well as a general framework within which to investigate electronic spin texture at the Fermi surface of materials.

  6. Thermodynamic contribution and nearest-neighbor parameters of pseudouridine-adenosine base pairs in oligoribonucleotides

    PubMed Central

    Hudson, Graham A.; Bloomingdale, Richard J.; Znosko, Brent M.

    2013-01-01

    Pseudouridine (Ψ) is the most common noncanonical nucleotide present in naturally occurring RNA and serves a variety of roles in the cell, typically appearing where structural stability is crucial to function. Ψ residues are isomerized from native uridine residues by a class of highly conserved enzymes known as pseudouridine synthases. In order to quantify the thermodynamic impact of pseudouridylation on U-A base pairs, 24 oligoribonucleotides, 16 internal and eight terminal Ψ-A oligoribonucleotides, were thermodynamically characterized via optical melting experiments. The thermodynamic parameters derived from two-state fits were used to generate linearly independent parameters for use in secondary structure prediction algorithms using the nearest-neighbor model. On average, internally pseudouridylated duplexes were 1.7 kcal/mol more stable than their U-A counterparts, and terminally pseudouridylated duplexes were 1.0 kcal/mol more stable than their U-A equivalents. Due to the fact that Ψ-A pairs maintain the same Watson-Crick hydrogen bonding capabilities as the parent U-A pair in A-form RNA, the difference in stability due to pseudouridylation was attributed to two possible sources: the novel hydrogen bonding capabilities of the newly relocated imino group as well as the novel stacking interactions afforded by the electronic configuration of the Ψ residue. The newly derived nearest-neighbor parameters for Ψ-A base pairs may be used in conjunction with other nearest-neighbor parameters for accurately predicting the most likely secondary structure of A-form RNA containing Ψ-A base pairs. PMID:24062573

  7. Thermodynamic contribution and nearest-neighbor parameters of pseudouridine-adenosine base pairs in oligoribonucleotides.

    PubMed

    Hudson, Graham A; Bloomingdale, Richard J; Znosko, Brent M

    2013-11-01

    Pseudouridine (Ψ) is the most common noncanonical nucleotide present in naturally occurring RNA and serves a variety of roles in the cell, typically appearing where structural stability is crucial to function. Ψ residues are isomerized from native uridine residues by a class of highly conserved enzymes known as pseudouridine synthases. In order to quantify the thermodynamic impact of pseudouridylation on U-A base pairs, 24 oligoribonucleotides, 16 internal and eight terminal Ψ-A oligoribonucleotides, were thermodynamically characterized via optical melting experiments. The thermodynamic parameters derived from two-state fits were used to generate linearly independent parameters for use in secondary structure prediction algorithms using the nearest-neighbor model. On average, internally pseudouridylated duplexes were 1.7 kcal/mol more stable than their U-A counterparts, and terminally pseudouridylated duplexes were 1.0 kcal/mol more stable than their U-A equivalents. Due to the fact that Ψ-A pairs maintain the same Watson-Crick hydrogen bonding capabilities as the parent U-A pair in A-form RNA, the difference in stability due to pseudouridylation was attributed to two possible sources: the novel hydrogen bonding capabilities of the newly relocated imino group as well as the novel stacking interactions afforded by the electronic configuration of the Ψ residue. The newly derived nearest-neighbor parameters for Ψ-A base pairs may be used in conjunction with other nearest-neighbor parameters for accurately predicting the most likely secondary structure of A-form RNA containing Ψ-A base pairs.

  8. Skylab ATM/S-056 X-ray event analyzer: Instrument description, parameter determination, and analysis example (15 June 1973 1B/M3 flare)

    NASA Technical Reports Server (NTRS)

    Wilson, R. M.

    1976-01-01

    The Skylab ATM/S-056 X-Ray Event Analyzer, part of an X-ray telescope experiment, is described. The techniques employed in the analysis of its data to determine electron temperatures and emission measures are reviewed. The analysis of a sample event - the 15 June 1973 1B/M3 flare - is performed. Comparison of the X-Ray Event Analyzer data with that of the SolRad 9 observations indicates that the X-Ray Event Analyzer accurately monitored the sun's 2.5 to 7.25 A X-ray emission and to a lesser extent the 6.1 to 20 A emission. A mean average peak temperature of 15 million K at 1,412 UT and a mean average peak electron density (assuming a flare volume of 10 to the 13 power cu km) of 27 million/cu mm at 1,416 to 1,417 UT are deduced for the event. The X-Ray Event Analyzer data, having a 2.5 s time resolution, should be invaluable in comparisons with other high-time resolution data (e.g., radio bursts).

  9. Parameter dependence in the atmospheric decoherence of modally entangled photon pairs

    NASA Astrophysics Data System (ADS)

    Ibrahim, Alpha Hamadou; Roux, Filippus S.; Konrad, Thomas

    2014-11-01

    When a pair of photons that are entangled in terms of their transverse modes, such as an orbital angular momentum (OAM) basis, propagates through atmospheric turbulence, the scintillation causes a decay of the entanglement. Here, we use numerical simulations to study how this decoherence process depends on the various dimension parameters of the system. The relevant dimension parameters are the propagation distance, the wavelength, the beam radius, and the refractive index structure constant, indicating the strength of the turbulence. We show that beyond the weak scintillation regime, the entanglement evolution cannot be accurately modeled by a single phase screen that is specified by a single dimensionless parameter. Two dimensionless parameters are necessary to describe the OAM entanglement evolution. Furthermore, it is found that higher OAM modes are not more robust in turbulence beyond the weak scintillation regime.

  10. Correlation of leptin and soluble leptin receptor levels with anthropometric parameters in mother-newborn pairs

    PubMed Central

    Marino-Ortega, Linda A; Molina-Bello, Adiel; Polanco-García, Julio C; Muñoz-Valle, José F; Salgado-Bernabé, Aralia B; Guzmán-Guzmán, Iris P; Parra-Rojas, Isela

    2015-01-01

    The aim of this study was to investigate if anthropometric parameters are associated with both leptin and soluble leptin receptor (sLEPR) levels in newborns and their mothers. This cross-sectional study was performed in 118 mother-newborn pairs. The venous blood sample of mothers was taken before delivery and immediately after delivery an umbilical cord blood sample was collected. Levels of leptin and sLEPR in maternal and umbilical cord sera were assessed by ELISA. Maternal serum concentration of leptin and sLEPR (6.2 and 25.7 ng/ml, respectively) were higher than in umbilical cord blood (2.4 and 14.2 ng/ml, respectively). However, the newborns and their mothers had higher sLEPR levels than leptin levels. In mothers was observed that leptin levels increase with weight gain in pregnancy and decreased sLEPR levels. Cord leptin levels correlated with neonatal birth weight and length, the body circumferences, placental weight and maternal leptin levels. Cord sLEPR levels correlated with maternal sLEPR and leptin levels. Maternal serum concentration of leptin correlated with pre-pregnancy BMI, weight gain, cord sLEPR and leptin levels. Maternal sLEPR concentration correlated with cord sLEPR levels. The leptin and sLEPR levels in mother-newborn pairs are related with anthropometric parameters and an inverse correlation between leptin levels and sLEPR was observed in pairs. PMID:26379933

  11. Effects of pairing correlations on the inverse level density parameter of hot rotating nuclei

    NASA Astrophysics Data System (ADS)

    Thi Quynh Huong, Le; Quang Hung, Nguyen; Thi Quynh Trang, Le

    2016-06-01

    Angular momentum dependence of the inverse level density parameter K in the excitation-energy region of ˜ 30 - 40 MeV is studied within the finite-temperature Bardeen-Cooper-Schrieffer (FTBCS) theory and the FTBCS theory that includes the effect due to quasiparticle-number fluctuations (FTBCS1). The two theories take into account the noncollective rotation of the nucleus at nonzero values of z-projection M of the total angular momentum. The comparison between the results obtained within the FTBCS and FTBCS1 as well as the case without pairing correlations and the experimental data for two medium-mass even-even nuclei 108Cd and 122Te shows that by including the pairing corrections the FTBCS and FTBCS1 reproduces quite well all the experimental data, whereas the non-pairing case always overestimates the data. Due to the effect of quasiparticle-number fluctuations, the FTBCS1 gaps at different M values do not collapse at critical temperature TC as in the FTBCS ones but monotonously decrease with increasing T and being finite even at high T. As the result, the values of K obtained within the FTBCS1 are always closer to the experimental data than those obtained within the FTBCS.

  12. Detecting non-stationary hydrologic model parameters in a paired catchment system using data assimilation

    NASA Astrophysics Data System (ADS)

    Pathiraja, S.; Marshall, L.; Sharma, A.; Moradkhani, H.

    2016-08-01

    Non-stationarity represents one of the major challenges facing hydrologists. There exists a need to develop modelling systems that are capable of accounting for potential catchment changes, in order to provide useful predictions for the future. Such changes may be due to climatic temporal variations or human induced changes to land cover. Extensive research has been undertaken on the impacts of land-use change on hydrologic behaviour, however, few studies have examined this issue in a predictive modelling context. In this paper, we investigate whether a time varying model parameter estimation framework that uses the principles of Data Assimilation can improve prediction for two pairs of experimental catchments in Western Australia. All catchments were initially forested, but after three years one catchment was fully cleared whilst another had only 50% of its area cleared. Their adjacent catchments remained unchanged as a control. Temporal variations in parameters were detected for both treated catchments, with no comparable variations for the control catchments. Improved streamflow prediction and representation of soil moisture dynamics were also seen for the time varying parameter case, compared to when a time invariant parameter set from the calibration period was used. While we use the above mentioned catchments to illustrate the usefulness of the approach, the methods are generic and equally applicable in other settings. This study serves as an important validation step to demonstrate the potential for time varying model structures to improve both predictions and modelling of changing catchments.

  13. Graph theory for analyzing pair-wise data: application to geophysical model parameters estimated from interferometric synthetic aperture radar data at Okmok volcano, Alaska

    NASA Astrophysics Data System (ADS)

    Reinisch, Elena C.; Cardiff, Michael; Feigl, Kurt L.

    2016-07-01

    Graph theory is useful for analyzing time-dependent model parameters estimated from interferometric synthetic aperture radar (InSAR) data in the temporal domain. Plotting acquisition dates (epochs) as vertices and pair-wise interferometric combinations as edges defines an incidence graph. The edge-vertex incidence matrix and the normalized edge Laplacian matrix are factors in the covariance matrix for the pair-wise data. Using empirical measures of residual scatter in the pair-wise observations, we estimate the relative variance at each epoch by inverting the covariance of the pair-wise data. We evaluate the rank deficiency of the corresponding least-squares problem via the edge-vertex incidence matrix. We implement our method in a MATLAB software package called GraphTreeTA available on GitHub (https://github.com/feigl/gipht). We apply temporal adjustment to the data set described in Lu et al. (Geophys Res Solid Earth 110, 2005) at Okmok volcano, Alaska, which erupted most recently in 1997 and 2008. The data set contains 44 differential volumetric changes and uncertainties estimated from interferograms between 1997 and 2004. Estimates show that approximately half of the magma volume lost during the 1997 eruption was recovered by the summer of 2003. Between June 2002 and September 2003, the estimated rate of volumetric increase is (6.2 ± 0.6) × 10^6~m^3/year . Our preferred model provides a reasonable fit that is compatible with viscoelastic relaxation in the five years following the 1997 eruption. Although we demonstrate the approach using volumetric rates of change, our formulation in terms of incidence graphs applies to any quantity derived from pair-wise differences, such as range change, range gradient, or atmospheric delay.

  14. The pulse-pair algorithm as a robust estimator of turbulent weather spectral parameters using airborne pulse Doppler radar

    NASA Technical Reports Server (NTRS)

    Baxa, Ernest G., Jr.; Lee, Jonggil

    1991-01-01

    The pulse pair method for spectrum parameter estimation is commonly used in pulse Doppler weather radar signal processing since it is economical to implement and can be shown to be a maximum likelihood estimator. With the use of airborne weather radar for windshear detection, the turbulent weather and strong ground clutter return spectrum differs from that assumed in its derivation, so the performance robustness of the pulse pair technique must be understood. Here, the effect of radar system pulse to pulse phase jitter and signal spectrum skew on the pulse pair algorithm performance is discussed. Phase jitter effect may be significant when the weather return signal to clutter ratio is very low and clutter rejection filtering is attempted. The analysis can be used to develop design specifications for airborne radar system phase stability. It is also shown that the weather return spectrum skew can cause a significant bias in the pulse pair mean windspeed estimates, and that the poly pulse pair algorithm can reduce this bias. It is suggested that use of a spectrum mode estimator may be more appropriate in characterizing the windspeed within a radar range resolution cell for detection of hazardous windspeed gradients.

  15. Dynamics of a hypoid gear pair considering the effects of time-varying mesh parameters and backlash nonlinearity

    NASA Astrophysics Data System (ADS)

    Wang, Jun; Lim, Teik C.; Li, Mingfeng

    2007-11-01

    A generalized nonlinear time-varying (NLTV) dynamic model of a hypoid gear pair with backlash nonlinearity is formulated which is also applicable to spur, helical, spiral bevel and worm gears. Firstly, the fundamental harmonic form of time-varying mesh parameters is used to study the effects of mesh parameter variations on the dynamic response, and the interactions between them and backlash nonlinearity. The analysis also examines the effects of mean load and mesh damping. Secondly, based on a three-dimensional quasi-static tooth contact analysis, a new significantly more exact time-varying mesh model is proposed, which describes the true mesh characteristics of hypoid gear pairs. The enhanced time-varying mesh model is applied to perform further dynamic analysis. Computational results reveal numerous interesting nonlinear characteristics, such as jump discontinuities, sub-harmonic and chaotic behaviors, especially for lightly loaded and lightly damped cases.

  16. Studying temperature dependence of pairing gap parameter in a nucleus as a small superconducting system

    NASA Astrophysics Data System (ADS)

    Rahmatinejad, A.; Razavi, R.; Kakavand, T.

    2016-07-01

    In this paper, we have taken the effect of small size of nucleus and static fluctuations into account in the Bardeen-Cooper-Schrieffer (BCS) theory of superconductivity calculations of 45Ti nucleus. Thermodynamic quantities of 45Ti have been extracted within the BCS model with the inclusion of the average value of the pairing gap square, extracted by the modified Ginzburg-Landau (MGL) method for small systems. Calculated values of the excitation energy and entropy within the MGL+BCS method improve the extracted results within the usual BCS model and show a smooth behavior around the critical temperature with a very good agreement with the semi-empirical values. The result of using MGL+BCS method for the heat capacity of 45Ti is compared with the corresponding semi-empirical values and the calculated values within the BCS, static path approximation (SPA) and Modified Pairing gap BCS (MPBCS) which is a method that was proposed in our previous publications. Both MGL+BCS and MPBCS avoid the discontinuity of the heat capacity curve, which is observed in the usual BCS method, and lead to an S-shaped curve with a good agreement with the semi-empirical results.

  17. Comprehensive derivation of bond-valence parameters for ion pairs involving oxygen

    PubMed Central

    Gagné, Olivier Charles; Hawthorne, Frank Christopher

    2015-01-01

    Published two-body bond-valence parameters for cation–oxygen bonds have been evaluated via the root mean-square deviation (RMSD) from the valence-sum rule for 128 cations, using 180 194 filtered bond lengths from 31 489 coordination polyhedra. Values of the RMSD range from 0.033–2.451 v.u. (1.1–40.9% per unit of charge) with a weighted mean of 0.174 v.u. (7.34% per unit of charge). The set of best published parameters has been determined for 128 ions and used as a benchmark for the determination of new bond-valence parameters in this paper. Two common methods for the derivation of bond-valence parameters have been evaluated: (1) fixing B and solving for R o; (2) the graphical method. On a subset of 90 ions observed in more than one coordination, fixing B at 0.37 Å leads to a mean weighted-RMSD of 0.139 v.u. (6.7% per unit of charge), while graphical derivation gives 0.161 v.u. (8.0% per unit of charge). The advantages and disadvantages of these (and other) methods of derivation have been considered, leading to the conclusion that current methods of derivation of bond-valence parameters are not satisfactory. A new method of derivation is introduced, the GRG (generalized reduced gradient) method, which leads to a mean weighted-RMSD of 0.128 v.u. (6.1% per unit of charge) over the same sample of 90 multiple-coordination ions. The evaluation of 19 two-parameter equations and 7 three-parameter equations to model the bond-valence–bond-length relation indicates that: (1) many equations can adequately describe the relation; (2) a plateau has been reached in the fit for two-parameter equations; (3) the equation of Brown & Altermatt (1985 ▸) is sufficiently good that use of any of the other equations tested is not warranted. Improved bond-valence parameters have been derived for 135 ions for the equation of Brown & Altermatt (1985 ▸) in terms of both the cation and anion bond-valence sums using the GRG method and our complete data set. PMID

  18. Derivation of Pitzer Interaction Parameters for an Aqueous Species Pair of FeCitrate- and Mg2+

    NASA Astrophysics Data System (ADS)

    Jang, J.; Olivas, T.; Nemer, M.

    2013-12-01

    The Waste Isolation Pilot Plant (WIPP) is a deep underground repository for the disposal of transuranic (TRU) radioactive waste developed by the U.S. Department of Energy (DOE). The WIPP is located within the bedded salts of the Permian Salado Formation, which consists of interbedded halite and anhydrite layers overlaying the Castile Formation. The waste includes, but is not limited to, the salts of citric acid and iron. To calculate the solution chemistry for brines of WIPP-relevance, WIPP Performance Assessment (PA) employs the Pitzer formulation to determine the activity coefficients of aqueous species in brine. The current WIPP thermodynamic database, however, does not include iron species and their Pitzer parameters, in spite of the fact that there will be a large amount of iron in the WIPP. Iron would be emplaced as part of the waste, as well as the containers for the waste. The objective of this analysis is to derive the Pitzer binary interaction parameters for the pair of Mg2+ and FeCitrate-. Briefly, an aqueous model for dissolution of Fe(OH)2(s) in MgNa2Citrate solution was fitted to the experimentally measured solubility data. The aqueous model consists of several chemical reactions and related Pitzer interaction parameters. Specifically, Pitzer binary interaction parameters for the Mg2+ and FeCitrate- pair (β(0), β(1), and Cφ) were fitted to the experimental data. Anoxic gloveboxes were used to keep the oxygen level low (less than 6 ppm) throughout the experiments. Aging time was more than 800 days to ensure equilibrium. EQ3NR packaged in EQ3/6 v.8.0a calculates the aqueous speciation and saturation index using an aqueous model addressed in EQ3/6's database. The saturation index indicates how far the system is from equilibrium with respect to the solid of interest. Thus, the smaller the sum of squared saturation indices that the aqueous model calculates for the given number of experiments, the more closely the model attributes equilibrium to each

  19. Identification of the battery state-of-health parameter from input-output pairs of time series data

    NASA Astrophysics Data System (ADS)

    Li, Yue; Chattopadhyay, Pritthi; Ray, Asok; Rahn, Christopher D.

    2015-07-01

    As a paradigm of dynamic data-driven application systems (DDDAS), this paper addresses real-time identification of the State of Health (SOH) parameter over the life span of a battery that is subjected to approximately repeated cycles of discharging/recharging current. In the proposed method, finite-length data of interest are selected via wavelet-based segmentation from the time series of synchronized input-output (i.e., current-voltage) pairs in the respective two-dimensional space. Then, symbol strings are generated by partitioning the selected segments of the input-output time series to construct a special class of probabilistic finite state automata (PFSA), called D-Markov machines. Pertinent features of the statistics of battery dynamics are extracted as the state emission matrices of these PFSA. This real-time method of SOH parameter identification relies on the divergence between extracted features. The underlying concept has been validated on (approximately periodic) experimental data, generated from a commercial-scale lead-acid battery. It is demonstrated by real-time analysis of the acquired current-voltage data on in-situ computational platforms that the proposed method is capable of distinguishing battery current-voltage dynamics at different aging stages, as an alternative to computation-intensive and electrochemistry-dependent analysis via physics-based modeling.

  20. Derivation of Pitzer Interaction Parameters for an Aqueous Species Pair of Sodium and Iron(II)-Citrate Complex

    NASA Astrophysics Data System (ADS)

    Jang, J. H.; Nemer, M.

    2015-12-01

    The U.S. DOE Waste Isolation Pilot Plant (WIPP) is a deep underground repository for the permanent disposal of transuranic (TRU) radioactive waste. The WIPP is located in the Permian Delaware Basin near Carlsbad, New Mexico, U.S.A. The TRU waste includes, but is not limited to, iron-based alloys and the complexing agent, citric acid. Iron is also present from the steel used in the waste containers. The objective of this analysis is to derive the Pitzer activity coefficients for the pair of Na+ and FeCit- complex to expand current WIPP thermodynamic database. An aqueous model for the dissolution of Fe(OH)2(s) in a Na3Cit solution was fitted to the experimentally measured solubility data. The aqueous model consists of several chemical reactions and related Pitzer interaction parameters. Specifically, Pitzer interaction parameters for the Na+ and FeCit- pair (β(0), β(1), and Cφ) plus the stability constant for species of FeCit- were fitted to the experimental data. Anoxic gloveboxes were used to keep the oxygen level low (<1 ppm) throughout the experiments due to redox sensitivity. EQ3NR, a computer program for geochemical aqueous speciation-solubility calculations, packaged in EQ3/6 v.8.0a, calculates the aqueous speciation and saturation index using an aqueous model addressed in EQ3/6's database. The saturation index indicates how far the system is from equilibrium with respect to the solid of interest. Thus, the smaller the sum of squared saturation indices that the aqueous model calculates for the given number of experiments, the more closely the model attributes equilibrium to each individual experiment with respect to the solid of interest. The calculation of aqueous speciation and saturation indices was repeated by adjusting stability constant of FeCit-, β(0), β(1), and Cφ in the database until the values are found that make the sum of squared saturation indices the smallest for the given number of experiments. Results will be presented at the time of

  1. Calibration and data collection protocols for reliable lattice parameter values in electron pair distribution function (ePDF) studies

    DOE PAGES

    Abeykoon, A. M. Milinda; Hu, Hefei; Wu, Lijun; Zhu, Yimei; Billinge, Simon J. L.

    2015-02-01

    We explore and describe different protocols for calibrating electron pair distribution function (ePDF) measurements for quantitative studies on nano-materials. We find the most accurate approach to determine the camera-length is to use a standard calibration sample of Au nanoparticles from National Institute of Standards and Technology. Different protocols for data collection are also explored, as are possible operational errors, to find the best approaches for accurate data collection for quantitative ePDF studies.

  2. Theoretical investigations of the optical spectra and EPR parameters for the isolated and pairs of trivalent ytterbium ions in Li6Y(BO3)3 crystal

    NASA Astrophysics Data System (ADS)

    Liu, Hong-Gang; Zheng, Wen-Chen

    2015-11-01

    The optical spectra and electron paramagnetic resonance (EPR) parameters (g factors and hyperfine structure constants A) for an isolated Yb3+ ion in Li6Y(BO3)3 (LYB) crystal are investigated first by the complete diagonalization method based on the superposition model. The obtained results are in reasonable agreement with the experimental ones. For a pair of coupled Yb3+ ions in crystals, the extensively used formulas to calculate EPR splitting lines for such pair cannot be directly adopted in the present study and thus we extend them to the case of arbitrarily directed vector R connecting the two Yb3+ ions in crystal. By these amended formulas, we find that in addition to the interacting Yb3+ pair with nearest distance R (=0.385 nm), the Yb3+ pair with next-nearest distance R (=0.662 nm) would also make contribution to experimental EPR spectra. This point which was not noticed in previous works would help us further understand the energy transfer scheme between two Yb3+ ions in crystals.

  3. Pair Identity and Smooth Variation Rules Applicable for the Spectroscopic Parameters of H2O Transitions Involving High-J States

    NASA Technical Reports Server (NTRS)

    Ma, Q.; Tipping, R. H.; Lavrentieva, N. N.

    2010-01-01

    Two basic rules (i.e. the pair identity and the smooth variation) applicable for H2O transitions involving high-J states have been discovered. The origins of these rules are the properties of the energy levels and wavefunctions of H2O states with the quantum number J above certain boundaries. As a result, for lines involving high-J states in individually defined groups, all their spectroscopic parameters (i.e. the transition wavenumber, intensity, pressure-broadened half-width, pressure-induced shift, and temperature exponent) must follow these rules. One can use these rules to screen spectroscopic data provided by databases and to identify possible errors. In addition, by using extrapolation methods within the individual groups, one is able to predict the spectroscopic parameters for lines in this group involving very high-J states. The latter are required in developing high-temperature molecular spectroscopic databases such as HITEMP.

  4. log(MPl/m3/2)

    SciTech Connect

    Loaiza-Brito, Oscar; Martin, Johannes; Nilles, Hans Peter; Ratz, Michael

    2005-12-02

    Flux compactifications of string theory seem to require the presence of a fine-tuned constant in the superpotential. We discuss a scheme where this constant is replaced by a dynamical quantity which we argue to be a 'continuous Chern-Simons term'. In such a scheme, the gaugino condensate generates the hierarchically small scale of supersymmetry breakdown rather than adjusting its size to a constant. A crucial ingredient is the appearance of the hierarchically small quantity exp(-) which corresponds to the scale of gaugino condensation. Under rather general circumstances, this leads to a scenario of moduli stabilization, which is endowed with a hierarchy between the mass of the lightest modulus, the gravitino mass and the scale of the soft terms, mmodulus {approx} m3/2 {approx} 2 msoft. The 'little hierarchy' is given by the logarithm of the ratio of the Planck scale and the gravitino mass, {approx} log(MPl/m3/2) {approx} 4{pi}2. This exhibits a new mediation scheme of supersymmetry breakdown, called mirage mediation. We highlight the special properties of the scheme, and their consequences for phenomenology and cosmology.

  5. Orbital and physical parameters of eclipsing binaries from the ASAS catalogue - IX. Spotted pairs with red giants

    NASA Astrophysics Data System (ADS)

    Ratajczak, M.; Hełminiak, K. G.; Konacki, M.; Smith, A. M. S.; Kozłowski, S. K.; Espinoza, N.; Jordán, A.; Brahm, R.; Hempel, M.; Anderson, D. R.; Hellier, C.

    2016-09-01

    We present spectroscopic and photometric solutions for three spotted systems with red giant components. Absolute physical and orbital parameters for these double-lined detached eclipsing binary stars are presented for the first time. These were derived from the V-, and I-band ASAS and WASP photometry, and new radial velocities calculated from high quality optical spectra we obtained with a wide range of spectrographs and using the two-dimensional cross-correlation technique (TODCOR). All of the investigated systems (ASAS J184949-1518.7, BQ Aqr, and V1207 Cen) show the differential evolutionary phase of their components consisting of a main-sequence star or a subgiant and a red giant, and thus constitute very informative objects in terms of testing stellar evolution models. Additionally, the systems show significant chromospheric activity of both components. They can be also classified as classical RS CVn-type stars. Besides the standard analysis of radial velocities and photometry, we applied spectral disentangling to obtain separate spectra for both components of each analysed system which allowed for a more detailed spectroscopic study. We also compared the properties of red giant stars in binaries that show spots, with those that do not, and found that the activity phenomenon is substantially suppressed for stars with Rossby number higher than ˜1 and radii larger than ˜20 R⊙.

  6. The red dwarf pair GJ65 AB: inflated, spinning twins of Proxima. Fundamental parameters from PIONIER, NACO, and UVES observations

    NASA Astrophysics Data System (ADS)

    Kervella, P.; Mérand, A.; Ledoux, C.; Demory, B.-O.; Le Bouquin, J.-B.

    2016-10-01

    The nearby red dwarf binary GJ65 AB (UV+BL Ceti, M5.5Ve+M6Ve) is a cornerstone system to probe the physics of very low-mass stars. The radii of the two stars are currently known only from indirect photometric estimates, however, and this prevents us from using GJ65 AB as calibrators for the mass-radius (M-R) relation. We present new interferometric measurements of the angular diameters of the two components of GJ65 with the VLTI/PIONIER instrument in the near-infrared H band: θUD(A) = 0.558 ± 0.008 ± 0.020 mas and θUD(B) = 0.539 ± 0.009 ± 0.020 mas. They translate into limb-darkened angular diameters of θLD(A) = 0.573 ± 0.021 mas and θLD(B) = 0.554 ± 0.022 mas. Based on the known parallax, the linear radii are R(A) = 0.165 ± 0.006 R⊙ and R(B) = 0.159 ± 0.006 R⊙ (σ(R) /R = 4%). We searched for the signature of flares and faint companions in the interferometric visibilities and closure phases, but we did not identify any significant signal. We also observed GJ65 with the VLT/NACO adaptive optics and refined the orbital parameters and infrared magnitudes of the system. We derived masses for the two components of m(A) = 0.1225 ± 0.0043 M⊙ and m(B) = 0.1195 ± 0.0043 M⊙ (σ(m) /m = 4%). To derive the radial and rotational velocities of the two stars as well as their relative metallicity with respect to Proxima, we also present new individual UVES high-resolution spectra of the two components. Placing GJ65 A and B in the mass-radius diagram shows that their radii exceed expectations from recent models by 14 ± 4% and 12 ± 4%, respectively. Following previous theories, we propose that this discrepancy is caused by the inhibition of convective energy transport by a strong internal magnetic field generated by dynamo effect in these two fast-rotating stars. A comparison with the almost identical twin Proxima, which is rotating slowly, strengthens this hypothesis because the radius of Proxima does not appear to be inflated compared to models. Based on

  7. Magnetic isotope effect on kinetic parameters and quantum beats of radical pairs in micellar solution studied by optically detected esr using pulsed microwave.

    PubMed

    Kitahama, Yasutaka; Sakaguchi, Yoshio

    2008-01-17

    We investigated the quantum beats, the oscillation between singlet and triplet states of radical pairs induced by the microwave field resonant to one of the component radicals. They were observed as the alternation of the yields of the component radicals by a nanosecond time-resolved optical absorption with the X-band (9.15 GHz) resonant microwave pulse. This technique was applied to the photochemical reaction of benzophenone, benzophenone-d(10), and benzophenone-carbonyl-(13)C in a sodium dodecylsulfate micellar solution with a step-by-step increase of the resonant microwave pulse width. The yields of the component radicals showed alternation with an increase of the microwave pulse width. This indicates that the radical pair retains spin coherence in the micellar solution. The magnetic isotope effect on the amplitude of the quantum beat was observed. The MW effect on the quantum beat of BP-(13)C decreases from 80% to 60% of that of BP by irradiation of the pi-pulse MW due to spin-locking. The kinetic parameters were also determined using the X- or Ku-band (17.44 GHz) region. They are almost similar to each other except for the intersystem recombination rate in the system of BP-(13)C, which may be slightly higher than those in other systems.

  8. Formando planetas habitables en estrellas M3

    NASA Astrophysics Data System (ADS)

    Dugaro, A.; de Elía, G. C.; Brunini, A.

    2016-08-01

    Studies of stellar evolution allow us to infer that the low-mass stars are the most abundant in the galaxy. In the present investigation, we analyze the formation of planetary systems without gas giants around M3-type stars, which have a mass of 0.29 M. In particular, we are interested in studying the terrestrial-like planet formation processes and water delivery in the Habitable Zone (HZ) of those systems. To develop this investigation, we assume massive protoplanetary disks for such stars, which have 5 of the mass of the central star. Once defined the working disk, we use a semi-analytical model, which is able to determine the distribution of planetary embryos and planetesimals at the end of the gaseous phase. Then, these distributions are used as initial conditions for running -body simulations. Due to the stochastic nature of the accretion process, we carry out ten -body simulations in order to analyze the evolution of the planetary systems after the gas dissipation. Our results suggest the efficient formation of terrestrial-like planets in the HZ with a wide range of masses and water contents. The planets formed in the HZ of the system have masses between 0.07 M and 0.15 M and final water contents between 5.4 and 29 by mass. The physical properties of the terrestrial-like planets formed in the HZ of our simulations suggest that they should be able to retain a permanent and substantial atmosphere.

  9. Reassessment of the recombination parameters of chromium in n- and p-type crystalline silicon and chromium-boron pairs in p-type crystalline silicon

    SciTech Connect

    Sun, Chang Rougieux, Fiacre E.; Macdonald, Daniel

    2014-06-07

    Injection-dependent lifetime spectroscopy of both n- and p-type, Cr-doped silicon wafers with different doping levels is used to determine the defect parameters of Cr{sub i} and CrB pairs, by simultaneously fitting the measured lifetimes with the Shockley-Read-Hall model. A combined analysis of the two defects with the lifetime data measured on both n- and p-type samples enables a significant tightening of the uncertainty ranges of the parameters. The capture cross section ratios k = σ{sub n}/σ{sub p} of Cr{sub i} and CrB are determined as 3.2 (−0.6, +0) and 5.8 (−3.4, +0.6), respectively. Courtesy of a direct experimental comparison of the recombination activity of chromium in n- and p-type silicon, and as also suggested by modelling results, we conclude that chromium has a greater negative impact on carrier lifetimes in p-type silicon than n-type silicon with similar doping levels.

  10. Detecting to secret folded composite lamina package pairs in cores related slump dump structures and seismites with high resolution sampling of physical parameters

    NASA Astrophysics Data System (ADS)

    Acar, Dursun; Cagatay, Namik; Feray Meydan, Aysegul; Eris, Kadir; Sari, Erol; Akcer, Sena; Makaroglu, Ozlem; Alkislar, Hakan; Biltekin, Demet; Nagehan Arslan, Tugce

    2016-04-01

    The core retrieved from Lake Van consists of seismites that were possibly deposited during the earthquakes around the Van region. Deformed parts of the core sediments display folded laminations that can be attributed to seismites. The problem arises that if the fold axis is deposited perpendicular to the liner and, if the hinge line is far enough, describing the true laminations might be impossible related to real age of basin evolution because extra laminae seem deposited to the area. Scientist must pay attention such problem that dating method like varve counting and basin evolution estimates can totally change due to extra laminae that explained before. For eliminate to wrong interpretations considering reversal reflected anomalies even with angularity effects to one package of pair can show significant difference than other symmetric one due to angle of the hinge line or soft sediment deformation. Considering the situation explained, p-wave is not enough to support the idea however; chemical analyses (x-ray florescence), ICP-MS (asdasd) analysis can provide appropriate results to identify laminae that appear on the limbs of the reversed micro folds. New easy designed extra U-Channel drive tray framework prepared by us. U-Channels are prepared well conditioned, saturated enough to well contact between sediment surface and plastic shield of u-channel samples from cores. Physical parameters are measured by Multi sensor core logger (MSCL) with high resolution step ratio fixed to 1mm. At the p- wave and gamma ray results, we observed together stair upwards form and reverse reflected downward data graphics, thus our interpretation of identifying the fold limbs are now visible. We understand that laminae packages are exactly the same. XRF and MSCL are totally supporting to origin of pairs generated after their sedimentation age with mechanical forces. For this reason, in this study, we attended to solve such problem to analyze deformed folded laminations that must be

  11. Aminoxyl Radicals of B/P Frustrated Lewis Pairs: Refinement of the Spin-Hamiltonian Parameters by Field- and Temperature-Dependent Pulsed EPR Spectroscopy

    PubMed Central

    de Oliveira, Marcos; Knitsch, Robert; Sajid, Muhammad; Stute, Annika; Elmer, Lisa-Maria; Kehr, Gerald; Erker, Gerhard; Magon, Claudio J.; Jeschke, Gunnar; Eckert, Hellmut

    2016-01-01

    Q-band and X-band pulsed electron paramagnetic resonance spectroscopic methods (EPR) in the solid state were employed to refine the parameters characterizing the anisotropic interactions present in six nitroxide radicals prepared by N,N addition of NO to various borane-phosphane frustrated Lewis pairs (FLPs). The EPR spectra are characterized by the g-anisotropy as well as by nuclear hyperfine coupling between the unpaired electron and the 11B/10B, 14N and 31P nuclear magnetic moments. It was previously shown that continuous-wave spectra measured at X-band frequency (9.5 GHz) are dominated by the magnetic hyperfine coupling to 14N and 31P, whereas the g-tensor values and the 11B hyperfine coupling parameters cannot be refined with high precision from lineshape fitting. On the other hand, the X-band electron spin echo envelope modulation (ESEEM) and hyperfine sublevel correlation (HYSCORE) spectra are completely dominated by the nuclear hyperfine coupling to the 11B nuclei, allowing a selective determination of their interaction parameters. In the present work this analysis has been further validated by temperature dependent ESEEM measurements. In addition, pulsed EPR data measured in the Q-band (34 GHz) are reported, which present an entirely different situation: the g-tensor components can be measured with much higher precision, and the ESEEM and HYSCORE spectra contain information about all of the 10B, 11B, 14N and 31P hyperfine interaction parameters. Based on these new results, we report here high-accuracy and precision data of the EPR spin Hamiltonian parameters measured on six FLP-NO radical species embedded in their corresponding hydroxylamine host structures. While the ESEEM spectra at Q-band frequency turn out to be very complex (due to the multinuclear contribution to the overall signal) in the HYSCORE experiment the extension over two dimensions renders a better discrimination between the different nuclear species, and the signals arising from hyperfine

  12. Aminoxyl Radicals of B/P Frustrated Lewis Pairs: Refinement of the Spin-Hamiltonian Parameters by Field- and Temperature-Dependent Pulsed EPR Spectroscopy.

    PubMed

    de Oliveira, Marcos; Knitsch, Robert; Sajid, Muhammad; Stute, Annika; Elmer, Lisa-Maria; Kehr, Gerald; Erker, Gerhard; Magon, Claudio J; Jeschke, Gunnar; Eckert, Hellmut

    2016-01-01

    Q-band and X-band pulsed electron paramagnetic resonance spectroscopic methods (EPR) in the solid state were employed to refine the parameters characterizing the anisotropic interactions present in six nitroxide radicals prepared by N,N addition of NO to various borane-phosphane frustrated Lewis pairs (FLPs). The EPR spectra are characterized by the g-anisotropy as well as by nuclear hyperfine coupling between the unpaired electron and the 11B/10B, 14N and 31P nuclear magnetic moments. It was previously shown that continuous-wave spectra measured at X-band frequency (9.5 GHz) are dominated by the magnetic hyperfine coupling to 14N and 31P, whereas the g-tensor values and the 11B hyperfine coupling parameters cannot be refined with high precision from lineshape fitting. On the other hand, the X-band electron spin echo envelope modulation (ESEEM) and hyperfine sublevel correlation (HYSCORE) spectra are completely dominated by the nuclear hyperfine coupling to the 11B nuclei, allowing a selective determination of their interaction parameters. In the present work this analysis has been further validated by temperature dependent ESEEM measurements. In addition, pulsed EPR data measured in the Q-band (34 GHz) are reported, which present an entirely different situation: the g-tensor components can be measured with much higher precision, and the ESEEM and HYSCORE spectra contain information about all of the 10B, 11B, 14N and 31P hyperfine interaction parameters. Based on these new results, we report here high-accuracy and precision data of the EPR spin Hamiltonian parameters measured on six FLP-NO radical species embedded in their corresponding hydroxylamine host structures. While the ESEEM spectra at Q-band frequency turn out to be very complex (due to the multinuclear contribution to the overall signal) in the HYSCORE experiment the extension over two dimensions renders a better discrimination between the different nuclear species, and the signals arising from hyperfine

  13. Critical Schwinger Pair Production.

    PubMed

    Gies, Holger; Torgrimsson, Greger

    2016-03-01

    We investigate Schwinger pair production in spatially inhomogeneous electric backgrounds. A critical point for the onset of pair production can be approached by fields that marginally provide sufficient electrostatic energy for an off-shell long-range electron-positron fluctuation to become a real pair. Close to this critical point, we observe features of universality which are analogous to continuous phase transitions in critical phenomena with the pair-production rate serving as an order parameter: electric backgrounds can be subdivided into universality classes and the onset of pair production exhibits characteristic scaling laws. An appropriate design of the electric background field can interpolate between power-law scaling, essential Berezinskii-Kosterlitz-Thouless-type scaling, and a power-law scaling with log corrections. The corresponding critical exponents only depend on the large-scale features of the electric background, whereas the microscopic details of the background play the role of irrelevant perturbations not affecting criticality. PMID:26991162

  14. Pick a Pair. Pancake Pairs

    ERIC Educational Resources Information Center

    Miller, Pat

    2005-01-01

    Cold February weather and pancakes are a traditional pairing. Pancake Day began as a way to eat up the foods that were abstained from in Lent--traditionally meat, fat, eggs and dairy products. The best-known pancake event is The Pancake Day Race in Buckinghamshire, England, which has been run since 1445. This column describes pairs of books that…

  15. Tissue Regeneration in Urodela on Foton-M3

    NASA Astrophysics Data System (ADS)

    Grigoryan, E. N.; Poplinskaya, V. A.; Domaratskaya, E. I.; Novikova, Y. P.; Aleinikova, K. S.; Dvorochkin, N.; Almeida, E. A. C.

    2008-06-01

    In the experiment "Regeneration" flown on Foton-M3 in 2007 we continued our study of tissue and organ regeneration in Urodela. Special attention was given to the regulatory mechanisms that could induce peculiarities of regeneration during the spaceflight. The results obtained showed that lens regeneration in space-flown animals was synchronized and about 0.5 to 1 stage more advanced than in synchronous 1g controls. In both groups of animals cytokine FGFb expression increased in parallel with lens cell mitotic activity and was localized in the growth zone and iris of regenerating eyes. Lens regeneration was also accompanied by an increase of stress protein (HSP90) expression in retinal macroglia. Evaluation of HSP90 and FGFb expression by immuno-staining showed that it was higher in the eyes of space-flown animals than in synchronous controls. BrdU assay demonstrated incorporation of the precursor into populations of DNA synthesizing cells in both animal groups and mirrored cell growth in regenerating tissues. Tail regeneration in space-flown and synchronous control animals reached the stages IV to V. Computer morphometry showed that tail size parameters were similar though the tail area was slightly decreased in the space-flown newts. In contrast, remarkable changes in tail tip morphology were found between animal groups: flight and aquarium-control tail regenerates were identical in shape, while synchronous controls developed distinct dorsoventral asymmetry. Histological examinations suggested that morphogenetic differences were caused by different rates of epidermal cell growth in tail regenerates of newts exposed to microgravity and 1 g.

  16. The Moon mineralogy mapper (M3) on Chandrayaan-1

    USGS Publications Warehouse

    Pieters, C.M.; Boardman, J.; Buratti, B.; Chatterjee, A.; Clark, R.; Glavich, T.; Green, R.; Head, J.; Isaacson, P.; Malaret, E.; McCord, T.; Mustard, J.; Petro, N.; Runyon, C.; Staid, M.; Sunshine, J.; Taylor, L.; Tompkins, S.; Varanasi, P.; White, M.

    2009-01-01

    The Moon Mineralogy Mapper (M3) is a NASA-supported guest instrument on ISRO's remote sensing mission to Moon, Chandrayaan-1. The M3 is an imaging spectrometer that operates from the visible into the near-infrared (0.42-3.0 ??m) where highly diagnostic mineral absorption bands occur. Over the course of the mission M3 will provide low resolution spectroscopic data for the entire lunar surface at 140 m/pixel (86 spectral channels) to be used as a base-map and high spectral resolution science data (80 m/pixel; 260 spectral channels) for 25-50% of the surface. The detailed mineral assessment of different lunar terrains provided by M3 is principal information needed for understanding the geologic evolution of the lunar crust and lays the foundation for focused future in-depth exploration of the Moon.

  17. Mars Methane Analogue Mission (M3): Analytical Techniques and Operations

    NASA Astrophysics Data System (ADS)

    Cloutis, E.; Vrionis, H.; Qadi, A.; Bell, J. F.; Berard, G.; Boivin, A.; Ellery, A.; Jamroz, W.; Kruzelecky, R.; Mann, P.; Samson, C.; Stromberg, J.; Strong, K.; Tremblay, A.; Whyte, L.; Wing, B.

    2011-03-01

    The Mars Methane Analogue Mission (M3) project is designed to simulate a rover-based search for, and analysis of, methane sources on Mars at a serpentinite open pit mine in Quebec, using a variety of instruments.

  18. Effects of an essential fatty acid deficiency, pair-feeding and level of dietary corn oil on the hypothalamic-pituitary-gonadal axis and other physiological parameters in the male chicken.

    PubMed

    Engster, H M; Carew, L B; Cunningham, F J

    1978-06-01

    Two studies were conducted to observe the effects of an essential fatty acid (EFA) deficiency, added dietary corn oil and pair-feeding on growth, reproduction and other physiological parameters in the mature cockerel. A purified, linoleic acid (LA)-deficient diet (0.01% LA), or additions of 5% (3.01% LA) or 15% (9.04% LA) corn oil, were fed ad libitum from hatching through 24 weeks of age. Reductions in growth, feed consumption, and comb, and testes size, incomplete spermatogenesis, increased tissue eicosatrienoic acid (20: 3 omega 9) and changes in weights of selected internal organs were observed in deficient cockerels. Total pituitary gonadotropic activity was measured by two bioassay procedures and blood luteinizing hormone was measured by radioimmunoassay. By maturity both of these parameters were significantly reduced in deficient chickens. When these chickens were fed diets with 5% or 15% corn oil under pair-feeding or ad libitum conditions from 20 to 24 weeks, the reduced growth, comb and testes size and gonadotropin metabolism appeared to be caused by depressions in appetite and energy intake rather than EFA per se. The degenerate testicular histology of the 20-week old deficient cockerels, while responding fully to the ad libitum intake of the diets containing corn oil, showed only partial rehabilitation of spermatogenesis when diets with either 5% or 15% corn oil were pair-fed. In general, increasing the level of dietary fat from 5% to 15% did not cause many physiological changes.

  19. Resonantly paired fermionic superfluids

    NASA Astrophysics Data System (ADS)

    Gurarie, V.; Radzihovsky, L.

    2007-01-01

    We present a theory of a degenerate atomic Fermi gas, interacting through a narrow Feshbach resonance, whose position and therefore strength can be tuned experimentally, as demonstrated recently in ultracold trapped atomic gases. The distinguishing feature of the theory is that its accuracy is controlled by a dimensionless parameter proportional to the ratio of the width of the resonance to Fermi energy. The theory is therefore quantitatively accurate for a narrow Feshbach resonance. In the case of a narrow s-wave resonance, our analysis leads to a quantitative description of the crossover between a weakly paired BCS superconductor of overlapping Cooper pairs and a strongly paired molecular Bose-Einstein condensate of diatomic molecules. In the case of pairing via a p-wave resonance, that we show is always narrow for a sufficiently low density, we predict a detuning-temperature phase diagram, that in the course of a BCS-BEC crossover can exhibit a host of thermodynamically distinct phases separated by quantum and classical phase transitions. For an intermediate strength of the dipolar anisotropy, the system exhibits a px + i py paired superfluidity that undergoes a topological phase transition between a weakly coupled gapless ground state at large positive detuning and a strongly paired fully gapped molecular superfluid for a negative detuning. In two dimensions the former state is characterized by a Pfaffian ground state exhibiting topological order and non-Abelian vortex excitations familiar from fractional quantum Hall systems.

  20. M3D project for simulation studies of plasmas

    SciTech Connect

    Park, W.; Belova, E.V.; Fu, G.Y.; Strauss, H.R.; Sugiyama, L.E.

    1998-12-31

    The M3D (Multi-level 3D) project carries out simulation studies of plasmas of various regimes using multi-levels of physics, geometry, and mesh schemes in one code package. This paper and papers by Strauss, Sugiyama, and Belova in this workshop describe the project, and present examples of current applications. The currently available physics models of the M3D project are MHD, two-fluids, gyrokinetic hot particle/MHD hybrid, and gyrokinetic particle ion/two-fluid hybrid models. The code can be run with both structured and unstructured meshes.

  1. Quality Assurance Information for R Packages "aqfig" and "M3"

    EPA Science Inventory

    R packages “aqfig" and “M3" are optional modules for use with R statistical software (http://www.r-project.org). Package “aqfig" contains functions to aid users in the preparation of publication-quality figures for the display of air quality and other environmental data (e.g., le...

  2. A Pair of Identical Twins Discordant for Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Differ in Physiological Parameters and Gut Microbiome Composition

    PubMed Central

    Giloteaux, Ludovic; Hanson, Maureen R.; Keller, Betsy A.

    2016-01-01

    Patient: Male, 34 Final Diagnosis: ME/CFS Symptoms: Exertion intolerance • loss of functional capacity • pain • severe fatigue Medication: — Clinical Procedure: Cardiopulmonary exercise test Specialty: Sports Medicine Objective: Unknown ethiology Background: Patients with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) present with profound fatigue, flu-like symptoms, pain, cognitive impairment, orthostatic intolerance, post-exertional malaise (PEM), and exacerbation of some or all of the baseline symptoms. Case Report: We report on a pair of 34-year-old monozygotic twins discordant for ME/CFS, with WELL, the non-affected twin, and ILL, the affected twin. Both twins performed a two-day cardiopulmonary exercise test (CPET), preand post-exercise blood samples were drawn, and both provided stool samples for biochemical and molecular analyses. At peak exertion for both CPETs, ILL presented lower VO2peak and peak workload compared to WELL. WELL demonstrated normal reproducibility of VO2@ventilatory/anaerobic threshold (VAT) during CPET2, whereas ILL experienced an abnormal reduction of 13% in VAT during CPET2. A normal rise in lactate dehydrogenase (LDH), creatine kinase (CK), adrenocorticotropic hormone (ACTH), cortisol, creatinine, and ferritin content was observed following exercise for both WELL and ILL at each CPET. ILL showed higher increases of resistin, soluble CD40 ligand (sCD40L), and soluble Fas ligand (sFasL) after exercise compared to WELL. The gut bacterial microbiome and virome were examined and revealed a lower microbial diversity in ILL compared to WELL, with fewer beneficial bacteria such as Faecalibacterium and Bifidobacterium, and an expansion of bacteriophages belonging to the tailed dsDNA Caudovirales order. Conclusions: Results suggest dysfunctional immune activation in ILL following exercise and that prokaryotic viruses may contribute to mucosal inflammation and bacterial dysbiosis. Therefore, a two-day CPET and molecular

  3. Exploring the Mineralogy of the Moon with M3

    NASA Technical Reports Server (NTRS)

    Pieters, C. M.; Boardman, J.; Buratti, B.; Clark, R.; Green, R.; Head, J. W. III; McCord, T. B.; Mustard, J.; Runyon, C.; Staid, M.

    2006-01-01

    From the initial era or lunar exploration, we have learned that many processes active on the early Moon are common to most terrestrial planets, including the record of early and late impact bombardment. Since most major geologic activity ceased on the Moon approx. 3 Gy ago, the Moon's surface provides a record of the earliest era of terrestrial planet evolution. The type and composition of minerals that comprise a planetary surface are a direct result of the initial composition and subsequent thermal and physical processing. Lunar mineralogy seen today is thus a direct record of the early evolution of the lunar crust and subsequent geologic processes. Specifically, the distribution and concentration of specific minerals is closely tied to magma ocean products, lenses of intruded or remelted plutons, basaltic volcanism and fire-fountaining, and any process (e.g. cratering) that might redistribute or transform primary and secondary lunar crustal materials. The Moon Mineralogy Mapper (M3, or "m-cube") is a state-of-the-art imaging spectrometer that will fly on Chandrayaan-1, the Indian Space Research Organization (ISRO) mission to be launched late 2007 to early 2008. M3 is one of several foreign instruments chosen by ISRO to be flown on Chandrayaan-1 to complement the strong ISRO payload package. M3 was selected through a peer-review process as part of NASA s Discovery Program. It is under the oversight of PI Carle Pieters at Brown University and is being built by an experienced team at the Jet Propulsion Laboratory. Data analysis and calibration are carried out by a highly qualified and knowledgeable Science Team. To characterize diagnostic properties of lunar minerals, M3 acquires high spectral resolution reflectance data from 700 to 3000 nm (optional to 430 nm). M3 operates as a pushbroom spectrometer with a slit oriented orthogonal to the S/C orbital motion. Measurements are obtained simultaneously for 640 cross track spatial elements and 261 spectral elements

  4. Higher Order Lagrange Finite Elements In M3D

    SciTech Connect

    J. Chen; H.R. Strauss; S.C. Jardin; W. Park; L.E. Sugiyama; G. Fu; J. Breslau

    2004-12-17

    The M3D code has been using linear finite elements to represent multilevel MHD on 2-D poloidal planes. Triangular higher order elements, up to third order, are constructed here in order to provide M3D the capability to solve highly anisotropic transport problems. It is found that higher order elements are essential to resolve the thin transition layer characteristic of the anisotropic transport equation, particularly when the strong anisotropic direction is not aligned with one of the Cartesian coordinates. The transition layer is measured by the profile width, which is zero for infinite anisotropy. It is shown that only higher order schemes have the ability to make this layer converge towards zero when the anisotropy gets stronger and stronger. Two cases are considered. One has the strong transport direction partially aligned with one of the element edges, the other doesn't have any alignment. Both cases have the strong transport direction misaligned with the grid line by some angles.

  5. Extremal Positive Maps on M3(ℂ) and Idempotent Matrices

    NASA Astrophysics Data System (ADS)

    Miller, Marek; Olkiewicz, Robert

    2016-03-01

    A new method of analysing positive bistochastic maps on the algebra of complex matrices M3 has been proposed. By identifying the set of such maps with a convex set of linear operators on ℝ8, one can employ techniques from the theory of compact semigroups to obtain results concerning asymptotic properties of positive maps. It turns out that the idempotent elements play a crucial role in classifying the convex set into subsets, in which representations of extremal positive maps are to be found. It has been shown that all positive bistochastic maps, extremal in the set of all positive maps of M3, that are not Jordan isomorphisms of M3 are represented by matrices that fall into two possible categories, determined by the simplest idempotent matrices: one by the zero matrix, and the other by a one-dimensional orthogonal projection. Some norm conditions for matrices representing possible extremal maps have been specified and examples of maps from both categories have been brought up, based on the results published previously.

  6. Metal Matrix Microencapsulated (M3) fuel neutronics performance in PWRs

    SciTech Connect

    Fratoni, Massimiliano; Terrani, Kurt A

    2012-01-01

    Metal Matrix Microencapsulated (M3) fuel consists of TRISO or BISO coated fuel particles directly dispersed in a matrix of zirconium metal to form a solid rod (Fig. 1). In this integral fuel concept the cladding tube and the failure mechanisms associated with it have been eliminated. In this manner pellet-clad-interactions (PCI), thin tube failure due to oxidation and hydriding, and tube pressurization and burst will be absent. M3 fuel, given the high stiffness of the integral rod design, could as well improve grid-to-rod wear behavior. Overall M3 fuel, compared to existing fuel designs, is expected to provide greatly improved operational performance. Multiple barriers to fission product release (ceramic coating layers in the coated fuel particle and te metal matrix) and the high thermal conductivity zirconium alloy metal matrix contribute to the enhancement in fuel behavior. The discontinuous nature of fissile material encapsulated in coated particles provides additional assistance; for instance if the M3 fuel rod is snapped into multiple pieces, only the limited number of fuel particles at the failure cross section are susceptible to release fission products. This is in contrast to the conventional oxide fuel where the presence of a small opening in the cladding provides the pathway for release of the entire inventory of fission products from the fuel rod. While conventional metal fuels (e.g. U-Zr and U-Mo) are typically expected to experience large swelling under irradiation due to the high degree of damage from fission fragments and introduction of fission gas into the lattice, this is not the case for M3 fuels. The fissile portion of the fuel is contained within the coated particle where enough room is available to accommodate fission gases and kernel swelling. The zirconium metal matrix will not be exposed to fission products and its swelling is known to be very limited when exposed solely to neutrons. Under design basis RIA and LOCA, fuel performance will be

  7. Identification of an H2-M3-Restricted Listeria Epitope: Implications for Antigen Presentation by M3

    PubMed Central

    Lenz, Laurel L.; Dere, Beverley; Bevan, Michael J.

    2009-01-01

    Summary Using expression cloning, we have identified an H2-M3-restricted epitope of the intracellular bacterial pathogen Listeria monocytogenes. Picomolar concentrations of an amino-terminal N-formylated hexapeptide, fMIGWII, targeted cells for lysis by CD8+ cytotoxic T cells, while the nonformylated peptide was approximately 100-fold less active. The sequence of the 185 aa protein source of this epitope predicts a transmembrane protein that retains its N terminus and assumes an Nout–Cin topology. This membrane orientation offers an explanation for the protection of the epitope from deformylases present in the bacterial cell and suggests an explanation for the ability of phagocytes to present H2-M3-restricted bacterial epitopes via a vacuolar TAP-independent mechanism. PMID:8758895

  8. Structure and dynamics of the M3 muscarinic acetylcholine receptor

    SciTech Connect

    Kruse, Andrew C.; Hu, Jianxin; Pan, Albert C.; Arlow, Daniel H.; Rosenbaum, Daniel M.; Rosemond, Erica; Green, Hillary F.; Liu, Tong; Chae, Pil Seok; Dror, Ron O.; Shaw, David E.; Weis, William I.; Wess, Jürgen; Kobilka, Brian K.

    2012-03-01

    Acetylcholine, the first neurotransmitter to be identified, exerts many of its physiological actions via activation of a family of G-protein-coupled receptors (GPCRs) known as muscarinic acetylcholine receptors (mAChRs). Although the five mAChR subtypes (M1-M5) share a high degree of sequence homology, they show pronounced differences in G-protein coupling preference and the physiological responses they mediate. Unfortunately, despite decades of effort, no therapeutic agents endowed with clear mAChR subtype selectivity have been developed to exploit these differences. We describe here the structure of the G{sub q/11}-coupled M3 mAChR ('M3 receptor', from rat) bound to the bronchodilator drug tiotropium and identify the binding mode for this clinically important drug. This structure, together with that of the G{sub i/o}-coupled M2 receptor, offers possibilities for the design of mAChR subtype-selective ligands. Importantly, the M3 receptor structure allows a structural comparison between two members of a mammalian GPCR subfamily displaying different G-protein coupling selectivities. Furthermore, molecular dynamics simulations suggest that tiotropium binds transiently to an allosteric site en route to the binding pocket of both receptors. These simulations offer a structural view of an allosteric binding mode for an orthosteric GPCR ligand and provide additional opportunities for the design of ligands with different affinities or binding kinetics for different mAChR subtypes. Our findings not only offer insights into the structure and function of one of the most important GPCR families, but may also facilitate the design of improved therapeutics targeting these critical receptors.

  9. The Chemical Composition Contrast between M3 and M13 Revisited: New Abundances for 28 Giant Stars in M3

    NASA Astrophysics Data System (ADS)

    Sneden, Christopher; Kraft, Robert P.; Guhathakurta, Puragra; Peterson, Ruth C.; Fulbright, Jon P.

    2004-04-01

    We report new chemical abundances of 23 bright red giant members of the globular cluster M3, based on high-resolution (R~45,000) spectra obtained with the Keck I telescope. The observations, which involve the use of multislits in the HIRES Keck I spectrograph, are described in detail. Combining these data with a previously reported small sample of M3 giants obtained with the Lick 3 m telescope, we compare metallicities and [X/Fe] ratios for 28 M3 giants with a 35-star sample in the similar-metallicity cluster M13, and with Galactic halo field stars having [Fe/H]<-1. For elements having atomic number A>=A(Si), we derive little difference in [X/Fe] ratios in the M3, M13, or halo field samples. All three groups exhibit C depletion with advancing evolutionary state beginning at the level of the red giant branch ``bump,'' but the overall depletion of about 0.7-0.9 dex seen in the clusters is larger than that associated with the field stars. The behaviors of O, Na, Mg, and Al are distinctively different among the three stellar samples. Field halo giants and subdwarfs have a positive correlation of Na with Mg, as predicted from explosive or hydrostatic carbon burning in Type II supernova sites. Both M3 and M13 show evidence of high-temperature proton-capture synthesis from the ON, NeNa, and MgAl cycles, while there is no evidence for such synthesis among halo field stars. But the degree of such extreme proton-capture synthesis in M3 is smaller than it is in M13: the M3 giants exhibit only modest deficiencies of O and corresponding enhancements of Na, less extreme overabundances of Al, fewer stars with low Mg and correspondingly high Na, and no indication that O depletions are a function of advancing evolutionary state, as has been claimed for M13. We have also considered NGC 6752, for which Mg isotopic abundances have been reported by Yong et al. Giants in NGC 6752 and M13 satisfy the same anticorrelation of O abundances with the ratio (25Mg+26Mg)/24Mg, which measures the

  10. Rise of [Ca²⁺]i and apoptosis induced by M-3M3FBS in SCM1 human gastric cancer cells.

    PubMed

    Chen, Wei-Chuan; Chou, Chiang-Ting; Liou, Wen-Chin; Liu, Shiuh-Inn; Lin, Ko-Long; Lu, Ti; Lu, Yi-Chau; Hsu, Shu-Shong; Tsai, Jeng-Yu; Liao, Wei-Chuan; Liang, Wei-Zhe; Jan, Chung-Ren

    2014-02-28

    M-3M3FBS (2,4,6-trimethyl-N-(meta-3-trifluoromethyl-phenyl)-benzenesulfonamide is a presumed phospholipase C activator which induced Ca²⁺ movement and apoptosis in different cell models. How- ever, the effect of m-3M3FBS on cytosolic free Ca²⁺ concentrations ([Ca²⁺]i) and apoptosis in SCM1 human gastric cancer cells is unclear. This study explored whether m-3M3FBS elevated basal [Ca²⁺]i levels in suspended cells by using fura-2 as a Ca²⁺-sensitive fluorescent dye. M-3M3FBS at concentrations between 5-50 μM increased [Ca²⁺]i in a concentration-dependent manner. The Ca²⁺ signal was reduced by half by removing extracellular Ca²⁺. M-3M3FBS-induced Ca²⁺ influx was inhibited by nifedipine, econazole, SK&F96365, aristolochic acid, and GF109203X. In Ca²⁺-free medium, 50 μM m-3M3FBS pretreatment inhibited the [Ca²⁺]i rise induced by the endoplasmic reticulum Ca²⁺ pump inhibitor thapsigargin. Conversely, pretreatment with thapsigargin partly reduced m-3M3FBS-induced [Ca²⁺]i rise. Suppression of inositol 1,4,5-trisphosphate production with U73122 did not change m-3M3FBS- induced [Ca²⁺]i rise. At concentrations between 25 and 50 μM m-3M3FBS killed cells in a concentration- dependent manner. The cytotoxic effect of m-3M3FBS was not reversed by prechelating cytosolic Ca²⁺ with acetoxy-methyl ester of bis-(o-aminophenoxy)-ethane-N,N,N',N'-tetraacetic acid (BAPTA/AM). Annexin V/propidium iodide staining data suggest that m-3M3FBS induced apoptosis at 25 and 50 μM. M-3M3FBS also increased levels of superoxide. Together, in human gastric cancer cells, m-3M3FBS induced a [Ca²⁺]i rise by inducing phospholipase C-independent Ca²⁺ release from the endoplasmic reticulum and Ca²⁺ entry via protein kinase C-sensitive store-operated Ca²⁺ channels. M-3M3FBS induced cell death that might involve apoptosis via reactive oxygen species production.

  11. Pairing Learners in Pair Work Activity

    ERIC Educational Resources Information Center

    Storch, Neomy; Aldosari, Ali

    2013-01-01

    Although pair work is advocated by major theories of second language (L2) learning and research findings suggest that pair work facilitates L2 learning, what is unclear is how to best pair students in L2 classes of mixed L2 proficiency. This study investigated the nature of pair work in an English as a Foreign Language (EFL) class in a college in…

  12. AT on Buried LPG Tanks Over 13 m3: An Innovative and Practical Solution

    NASA Astrophysics Data System (ADS)

    Di Fratta, Crescenzo; Ferraro, Antonio; Tscheliesnig, Peter; Lackner, Gerald; Correggia, Vincenzo; Altamura, Nicola

    In Italy, since 2005, techniques based on Acoustic Emission have been introduced for testing of underground LPG tanks up to 13 m3, according to the European standard EN 12818:2004. The testing procedure for these tanks plans to install one or more pairs of sensors inside the "dome" suited for the access to the valves and fittings of the tank, directly on the accessible metal shell. This methodology is not applicable for the underground LPG buried tanks, where it is necessary to install a larger number of AE sensors, in order to cover at 100% the whole tank shell, even at very deep positions. Already in 2004, the European standard EN 12820 (Appendix C - Informative)give the possibility to use Acoustic Emission testing of LPG underground or buried tanks with a capacity exceeding 13 m3, but no technique was specified for the application. In 2008, TÜV AUSTRIA ITALIA - BLU SOLUTIONS srl - Italian company of TÜV AUSTRIA Group - has developed a technique to get access at tank shell, where tank capacity is greater than 13 m3 and its' diameter greater than 3,5 m. This methodology was fully in comply with the provisions of the European Standard EN 12819:2010, becoming an innovative solution widely appreciated and is used in Italy since this time. Currently, large companies and petrochemical plants, at the occurrence of the tank's requalification, have engaged TÜV AUSTRIA ITALIA - BLU SOLUTIONS to install such permanent predispositions, which allow access to the tank shell - test object - with diameters from 4 to 8 m. Through this access, you can install the AE sensors needed to cover at 100% the tank surface and then to perform AE test. In an economic crisis period, this technique is proving a valid and practically applicable answer, in order to reduce inspection costs and downtime by offering a technically advanced solution (AT), increasing the safety of the involved operators, protecting natural resources and the environment.

  13. Goldschmidt crater and the Moon's north polar region: Results from the Moon Mineralogy Mapper (M3)

    USGS Publications Warehouse

    Cheek, L.C.; Pieters, C.M.; Boardman, J.W.; Clark, R.N.; Combe, J.-P.; Head, J.W.; Isaacson, P.J.; McCord, T.B.; Moriarty, D.; Nettles, J.W.; Petro, N.E.; Sunshine, J.M.; Taylor, L.A.

    2011-01-01

    Soils within the impact crater Goldschmidt have been identified as spectrally distinct from the local highland material. High spatial and spectral resolution data from the Moon Mineralogy Mapper (M3) on the Chandrayaan-1 orbiter are used to examine the character of Goldschmidt crater in detail. Spectral parameters applied to a north polar mosaic of M3 data are used to discern large-scale compositional trends at the northern high latitudes, and spectra from three widely separated regions are compared to spectra from Goldschmidt. The results highlight the compositional diversity of the lunar nearside, in particular, where feldspathic soils with a low-Ca pyroxene component are pervasive, but exclusively feldspathic regions and small areas of basaltic composition are also observed. Additionally, we find that the relative strengths of the diagnostic OH/H2O absorption feature near 3000 nm are correlated with the mineralogy of the host material. On both global and local scales, the strongest hydrous absorptions occur on the more feldspathic surfaces. Thus, M3 data suggest that while the feldspathic soils within Goldschmidt crater are enhanced in OH/H2O compared to the relatively mafic nearside polar highlands, their hydration signatures are similar to those observed in the feldspathic highlands on the farside. Copyright 2011 by the American Geophysical Union.

  14. Low-temperature M =3 flow deceleration by Lorentz force

    NASA Astrophysics Data System (ADS)

    Nishihara, Munetake; Rich, J. William; Lempert, Walter R.; Adamovich, Igor V.; Gogineni, Sivaram

    2006-08-01

    This paper presents results of cold magnetohydrodynamic (MHD) flow deceleration experiments using repetitively pulsed, short pulse duration, high voltage discharge to produce ionization in M =3 nitrogen and air flows in the presence of transverse direct current electric field and transverse magnetic field. MHD effect on the flow is detected from the flow static pressure measurements. Retarding Lorentz force applied to the flow produces a static pressure increase of up to 17%-20%, while accelerating force of the same magnitude results in static pressure increase of up to 5%-7%. The measured static pressure changes are compared with modeling calculations using quasi-one-dimensional MHD flow equations. Comparison of the experimental results with the modeling calculations shows that the retarding Lorentz force increases the static pressure rise produced by Joule heating of the flow, while the accelerating Lorentz force reduces the pressure rise. The effect is produced for two possible combinations of the magnetic field and transverse current directions producing the same Lorentz force direction (both for accelerating and retarding force). This demonstrates that the observed static pressure change is indeed due to the MHD interaction, and not due to Joule heating of the flow in the crossed discharge. No discharge polarity effect on the static pressure was detected in the absence of the magnetic field. The fraction of the discharge input power going into Joule heat in nitrogen and dry air, inferred from the present experiments, is low, α =0.1, primarily because energy remains frozen in the vibrational energy mode of nitrogen. This result provides first direct evidence of cold supersonic flow deceleration by Lorentz force.

  15. Low-temperature M=3 flow deceleration by Lorentz force

    SciTech Connect

    Nishihara, Munetake; Rich, J. William; Lempert, Walter R.; Adamovich, Igor V.; Gogineni, Sivaram

    2006-08-15

    This paper presents results of cold magnetohydrodynamic (MHD) flow deceleration experiments using repetitively pulsed, short pulse duration, high voltage discharge to produce ionization in M=3 nitrogen and air flows in the presence of transverse direct current electric field and transverse magnetic field. MHD effect on the flow is detected from the flow static pressure measurements. Retarding Lorentz force applied to the flow produces a static pressure increase of up to 17%-20%, while accelerating force of the same magnitude results in static pressure increase of up to 5%-7%. The measured static pressure changes are compared with modeling calculations using quasi-one-dimensional MHD flow equations. Comparison of the experimental results with the modeling calculations shows that the retarding Lorentz force increases the static pressure rise produced by Joule heating of the flow, while the accelerating Lorentz force reduces the pressure rise. The effect is produced for two possible combinations of the magnetic field and transverse current directions producing the same Lorentz force direction (both for accelerating and retarding force). This demonstrates that the observed static pressure change is indeed due to the MHD interaction, and not due to Joule heating of the flow in the crossed discharge. No discharge polarity effect on the static pressure was detected in the absence of the magnetic field. The fraction of the discharge input power going into Joule heat in nitrogen and dry air, inferred from the present experiments, is low, {alpha}=0.1, primarily because energy remains frozen in the vibrational energy mode of nitrogen. This result provides first direct evidence of cold supersonic flow deceleration by Lorentz force.

  16. Hemopoietic tissue in newts flown aboard Foton M3

    NASA Astrophysics Data System (ADS)

    Domaratskaya, Elena I.; Almeida, Eduardo; Butorina, Nina N.; Nikonova, Tatyana M.; Grigoryan, Eleonora N.; Poplinskaya, Valentina A.; Souza, Kenneth; Skidmore, Mike

    The effect of 12-day spaceflight aboard the Foton-M3 biosatellite on the hematopoietic tissue of P. waltl newts was studied. These animals used at the same time in regeneration experiments after lens and tail tip amputation. In flight and synchronous groups there were performed video recording, temperature and radiation monitoring and continuous contact (via skin) with thymidine analog BrdU. We took differential blood counts and assessed histologically the liver in the flight (F), basal (BC) and synchronous (SC)control groups of animals. In the peripheral blood, we identified neutrophils, eosinophils, basophils, lymphocytes, and monocytes. Lymphocytes (L) and neutrophils (N) prevailed, accounting for about 60 and 20% of white blood cells, respectively. The spaceflight had no apparent effect on the differential blood count in the F group: neither the L and N contents nor the maturing to mature N - ratio differed from those in the control groups. No significant differences between F, SC and BC groups were observed with respect to the structure of hematopoietic areas and the liver morphology. As in Foton-M2, BrdU labeled cells revealed in blood as well as in the hemopoietic areas of the liver. However, in previous experiments performed at satellites Bion-10 and Foton-M2 the changes in peripheral blood contents were registered in operated F newts, and we supposed it could be the result of additive effects of spaceflight factors and stimulation of reparative potency and stress due to surgical operation. Possibly, the temperature conditions also may provide some influence on blood cell content of newts that belong to poikilothermic animals. Thus, in present experiment F and SC groups were reared in the same temperature regims, whereas it was nearly 3o C differences between SC and F groups exposed on Foton-M2. At the same time as it was found in experiments on Bion-11 and Foton-M2 spaceflight factors did not affect on differential blood counts of intact non

  17. Powered Tate Pairing Computation

    NASA Astrophysics Data System (ADS)

    Kang, Bo Gyeong; Park, Je Hong

    In this letter, we provide a simple proof of bilinearity for the eta pairing. Based on it, we show an efficient method to compute the powered Tate pairing as well. Although efficiency of our method is equivalent to that of the Tate pairing on the eta pairing approach, but ours is more general in principle.

  18. A multilevel multiscale mimetic (M 3) method for two-phase flows in porous media

    NASA Astrophysics Data System (ADS)

    Lipnikov, K.; Moulton, J. D.; Svyatskiy, D.

    2008-07-01

    We describe a multilevel multiscale mimetic (M 3) method for solving two-phase flow (water and oil) in a heterogeneous reservoir. The governing equations are the elliptic equation for the reservoir pressure and the hyperbolic equation for the water saturation. On each time step, we first solve the pressure equation and then use the computed flux in an explicit upwind finite volume method to update the saturation. To reduce the computational cost, the pressure equation is solved on a much coarser grid than the saturation equation. The coarse-grid pressure discretization captures the influence of multiple scales via the subgrid modeling technique for single-phase flow recently proposed in [Yu. A. Kuznetsov. Mixed finite element method for diffusion equations on polygonal meshes with mixed cells. J. Numer. Math., 14 (4) (2006) 305-315; V. Gvozdev. discretization of the diffusion and Maxwell equations on polyhedral meshes. Technical Report Ph.D. Thesis, University of Houston, 2007; Yu. Kuznetsov. Mixed finite element methods on polyhedral meshes for diffusion equations, in: Computational Modeling with PDEs in Science and Engineering, Springer-Verlag, Berlin, in press]. We extend significantly the applicability of this technique by developing a new robust and efficient method for estimating the flux coarsening parameters. Specifically, with this advance the M 3 method can handle full permeability tensors and general coarsening strategies, which may generate polygonal meshes on the coarse grid. These problem dependent coarsening parameters also play a critical role in the interpolation of the flux, and hence, in the advection of saturation for two-phase flow. Numerical experiments for two-phase flow in highly heterogeneous permeability fields, including layer 68 of the SPE Tenth Comparative Solution Project, demonstrate that the M 3 method retains good accuracy for high coarsening factors in both directions, up to 64 for the considered models. Moreover, we demonstrate

  19. Two-Fluid Extensions to the M3D CDX-U Validation Study

    NASA Astrophysics Data System (ADS)

    Breslau, J.; Strauss, H.; Sugiyama, L.

    2005-10-01

    As part of a cross-code verification and validation effort, both the M3D code [1] and the NIMROD code [2] have qualitatively reproduced the nonlinear behavior of a complete sawtooth cycle in the CDX-U tokamak, chosen for the study because its low temperature and small size puts it in a parameter regime easily accessible to both codes. Initial M3D studies on this problem used a resistive MHD model with a large, empirical perpendicular heat transport value and with modest toroidal resolution (24 toroidal planes). The success of this study prompted the pursuit of more quantitatively accurate predictions by the application of more sophisticated physical models and higher numerical resolution. The results of two consequent follow-up studies are presented here. In the first, the toroidal resolution of the original run is doubled to 48 planes. The behavior of the sawtooth in this case is essentially the same as in the lower- resolution study. The sawtooth study has also been repeated using a two-fluid plasma model, with the effects of the &*circ;i term emphasized. The resulting mode rotation, as well as the effects on the reconnection rate (sawtooth crash time), sawtooth period, and overall stability are presented. [1] W. Park, et al., Phys. Plasmas 6, 1796 (1999). [2] C. Sovinec, et al., J. Comp. Phys. 195, 355 (2004).

  20. Stability and Uncertainty of Full Moment Tensor Solutions for M < 3.5 Induced Earthquakes

    NASA Astrophysics Data System (ADS)

    Boyd, O. S.; Dreger, D. S.

    2014-12-01

    The increase in earthquakes associated with industrial activities has created a need to investigate and characterize the source physics of induced seismicity. Many techniques and approaches are available to determine representative source parameters of these events. For M > 3.5 events, high quality seismic data from regional networks can be used to provide reasonable estimates of moment tensor solutions. In this investigation we explore various techniques and datasets to constrain full moment tensor solutions of M < 3.5 induced events, expanding upon the approach developed by Guilhem et al., 2014. Small magnitude events recorded by local seismic networks can yield good quality data with distinct body wave and converted phases depending upon the velocity structure and frequency range. Generating synthetic seismograms or Green's functions to accurately model these high frequency phases can be challenging. To investigate the variability associated with the choice of Green's functions, we test available codes to see how well they capture body wave phases. Other stability and uncertainty measures include the F-test, Jackknife test, residual bootstrap, and Network Sensitivity Solution, (Ford et al., 2009; Ford et al., 2010). Additional datasets to constrain the full moment tensor solution include P-wave first motions and amplitude ratios.

  1. Pairing forces in nuclei

    SciTech Connect

    Chasman, R.R.

    1996-12-31

    In this contribution, the author mentions some features of pairing forces that are unique to nuclei and cover some areas of major interest in nuclear structure research, that involve pairing. At the level of most nuclear structure studies, nuclei are treated as consisting of two kinds of fermions (protons and neutrons) in a valence space with rather few levels. These features give rise to unique aspects of pairing forces in nuclei: (1) n-p pairing in T = 0 as well as the usual T = 1 pairing that is characteristic of like fermions; (2) a need to correct pairing calculations for the (1/N) effects that can typically be neglected in superconducting solids. An issue of current concern is the nature of the pairing interaction: several recent studies suggest a need for a density dependent form of the pairing interaction. There is a good deal of feedback between the questions of accurate calculations of pairing interactions and the form and magnitude of the pairing interaction. Finally, the authors discuss some many-body wave functions that are a generalization of the BCS wave function form, and apply them to a calculation of energy level spacings in superdeformed rotational bands.

  2. Matched-pair classification

    SciTech Connect

    Theiler, James P

    2009-01-01

    Following an analogous distinction in statistical hypothesis testing, we investigate variants of machine learning where the training set comes in matched pairs. We demonstrate that even conventional classifiers can exhibit improved performance when the input data has a matched-pair structure. Online algorithms, in particular, converge quicker when the data is presented in pairs. In some scenarios (such as the weak signal detection problem), matched pairs can be generated from independent samples, with the effect not only doubling the nominal size of the training set, but of providing the structure that leads to better learning. A family of 'dipole' algorithms is introduced that explicitly takes advantage of matched-pair structure in the input data and leads to further performance gains. Finally, we illustrate the application of matched-pair learning to chemical plume detection in hyperspectral imagery.

  3. Paired watershed study design

    SciTech Connect

    Clausen, J.C.; Spooner, J.

    1993-09-01

    The purpose of the fact sheet is to describe the paired watershed approach for conducting nonpoint source (NPS) water quality studies. The basic approach requires a minimum of two watersheds - control and treatment - and two periods of study - calibration and treatment. The basis of the paired watershed approach is that there is a quantifiable relationship between paired water quality data for the two watersheds, and that this relationship is valid until a major change is made in one of the watersheds.

  4. Detecting a preformed pair phase: Response to a pairing forcing field

    NASA Astrophysics Data System (ADS)

    Tagliavini, A.; Capone, M.; Toschi, A.

    2016-10-01

    The normal state of strongly coupled superconductors is characterized by the presence of "preformed" Cooper pairs well above the superconducting critical temperature. In this regime, the electrons are paired, but they lack the phase coherence necessary for superconductivity. The existence of preformed pairs implies the existence of a characteristic energy scale associated with a pseudogap. Preformed pairs are often invoked to interpret systems where some signatures of pairing are present without actual superconductivity, but an unambiguous theoretical characterization of a preformed-pair system is still lacking. To fill this gap, we consider the response to an external pairing field of an attractive Hubbard model, which hosts one of the cleanest realizations of a preformed pair phase, and a repulsive model where s -wave superconductivity cannot be realized. Using dynamical mean-field theory to study this response, we identify the characteristic features which distinguish the reaction of a preformed pair state from a normal metal without any precursor of pairing. The theoretical detection of preformed pairs is associated with the behavior of the second derivative of the order parameter with respect to the external field, as confirmed by analytic calculations in limiting cases. Our findings provide a solid test bed for the interpretation of state-of-the-art calculations for the normal state of the doped Hubbard model in terms of d -wave preformed pairs and, in perspective, of nonequilibrium experiments in high-temperature superconductors.

  5. Vortex pairs on surfaces

    SciTech Connect

    Koiller, Jair

    2009-05-06

    A pair of infinitesimally close opposite vortices moving on a curved surface moves along a geodesic, according to a conjecture by Kimura. We outline a proof. Numerical simulations are presented for a pair of opposite vortices at a close but nonzero distance on a surface of revolution, the catenoid. We conjecture that the vortex pair system on a triaxial ellipsoid is a KAM perturbation of Jacobi's geodesic problem. We outline some preliminary calculations required for this study. Finding the surfaces for which the vortex pair system is integrable is in order.

  6. Pairing Beyond BCS

    NASA Astrophysics Data System (ADS)

    Volya, Alexander; Zelevinsky, Vladimir

    2013-01-01

    We concentrate on the specifics of the nuclear pairing problem from the standpoint of the BCS approach. We consider the properties of nuclear pairing which usually are not discussed in standard texts: how good is the BCS theory in nuclear context compared to the exact large-scale diagonalization, whether it can be improved by the particle number conservation, how to mark the phase transition regions in a mesoscopic system like a nucleus, how may effective many-body forces influence the formation and structure of the pairing condensate, what effect the decay instability has on the paired nuclear structure, etc.

  7. THE SWIFT UVOT STARS SURVEY. II. RR LYRAE STARS IN M3 AND M15

    SciTech Connect

    Siegel, Michael H.; Porterfield, Blair L.; Balzer, Benjamin G.; Hagen, Lea M. Z. E-mail: blp14@psu.edu E-mail: lea.zernow.hagen@gmail.com

    2015-10-15

    We present the first results of a near-ultraviolet (NUV) survey of RR Lyrae stars from the Ultraviolet Optical Telescope (UVOT) on board the Swift Gamma-ray Burst Mission. It is well-established that RR Lyrae stars have large amplitudes in the far- and near-ultraviolet. We have used UVOT’s unique wide-field NUV imaging capability to perform the first systematic NUV survey of variable stars in the Galactic globular clusters M3 and M15. We identify 280 variable stars, comprised of 275 RR Lyrae, 2 anomalous Cepheids, 1 classical Cepheid, 1 SX Phoenicis star, and 1 possible long-period or irregular variable. Only two of these are new discoveries. We compare our results to previous investigations and find excellent agreement in the periods with significantly larger amplitudes in the NUV. We map out, for the first time, an NUV Bailey diagram from globular clusters, showing the usual loci for fundamental mode RRab and first overtone RRc pulsators. We show the unique sensitivity of NUV photometry to both the temperatures and the surface gravities of RR Lyrae stars. Finally, we show evidence of an NUV period–metallicity–luminosity relationship. Future investigations will further examine the dependence of NUV pulsation parameters on metallicity and Oosterhoff classification.

  8. Pair contact process with diffusion of pairs

    NASA Astrophysics Data System (ADS)

    Santos, F. L.; Dickman, Ronald; Fulco, U. L.

    2011-03-01

    The pair contact process (PCP) is a nonequilibrium stochastic model which, like the basic contact process (CP), exhibits a phase transition to an absorbing state. The two models belong to the directed percolation (DP) universality class, despite the fact that the PCP possesses infinitely many absorbing configurations whereas the CP has but one. The critical behavior of the PCP with hopping by particles (PCPD) is as yet unclear. Here we study a version of the PCP in which nearest-neighbor particle pairs can hop but individual particles cannot. Using quasistationary simulations for three values of the diffusion probability (D = 0.1, 0.5 and 0.9), we find convincing evidence of DP-like critical behavior.

  9. Cooper Pairs in Insulators?!

    SciTech Connect

    James Valles

    2008-07-23

    Nearly 50 years elapsed between the discovery of superconductivity and the emergence of the microscopic theory describing this zero resistance state. The explanation required a novel phase of matter in which conduction electrons joined in weakly bound pairs and condensed with other pairs into a single quantum state. Surprisingly, this Cooper pair formation has also been invoked to account for recently uncovered high-resistance or insulating phases of matter. To address this possibility, we have used nanotechnology to create an insulating system that we can probe directly for Cooper pairs. I will present the evidence that Cooper pairs exist and dominate the electrical transport in these insulators and I will discuss how these findings provide new insight into superconductor to insulator quantum phase transitions. 

  10. Cooper Pairs in Insulators?!

    ScienceCinema

    James Valles

    2016-07-12

    Nearly 50 years elapsed between the discovery of superconductivity and the emergence of the microscopic theory describing this zero resistance state. The explanation required a novel phase of matter in which conduction electrons joined in weakly bound pairs and condensed with other pairs into a single quantum state. Surprisingly, this Cooper pair formation has also been invoked to account for recently uncovered high-resistance or insulating phases of matter. To address this possibility, we have used nanotechnology to create an insulating system that we can probe directly for Cooper pairs. I will present the evidence that Cooper pairs exist and dominate the electrical transport in these insulators and I will discuss how these findings provide new insight into superconductor to insulator quantum phase transitions. 

  11. Retinal overexpression of Ten-m3 alters ipsilateral retinogeniculate projections in the wallaby (Macropus eugenii).

    PubMed

    Carr, Owen P; Glendining, Kelly A; Leamey, Catherine A; Marotte, Lauren R

    2014-04-30

    The dorsal lateral geniculate nucleus (dLGN) contains a retinotopic map where input from the two eyes map in register to provide a substrate for binocular vision. Ten-m3, a transmembrane protein, mediates homophilic interactions and has been implicated in the patterning of ipsilateral visual projections. Ease of access to early developmental stages in a marsupial wallaby has been used to manipulate levels of Ten-m3 during the development of retinogeniculate projections. In situ hybridisation showed a high dorsomedial to low ventrolateral gradient of Ten-m3 in the developing dLGN, matching retinotopically with the previously reported high ventral to low dorsal retinal gradient. Overexpression of Ten-m3 in ventronasal but not dorsonasal retina resulted in an extension of ipsilateral projections beyond the normal binocular zone. These results demonstrate that Ten-m3 influences ipsilateral projections and support a role for it in binocular mapping. PMID:24602979

  12. Real-time monitoring of genetically modified Chlamydomonas reinhardtii during the Foton M3 space mission

    NASA Astrophysics Data System (ADS)

    Lambreva, M.; Rea, G.; Antonacci, A.; Serafini, A.; Damasso, M.; Pastorelli, S.; Margonelli, A.; Johanningmeier, U.; Bertalan, I.; Pezzotti, G.; Giardi, M. T.

    2008-09-01

    . We analysed the hourly changes and the daily light/dark trend in the maximum quantum yield of PSII photochemistry, Fv/Fm (Fig.2). Some physiological parameters that characterize the post-flight effect on algae viability and photosynthetic performance were also determined. The dose and particle flux during Foton-M3 flight were monitored in real time by the active spectrum-dosimeter Liulin- Photo, mounted on the top of Photo-II fluorimeter (Fig.2). Liulin-Photo measurements provided information on the amount of the energy released on the samples and the quality of the incident ionizing radiation [3]. The space flight results in relationship with the ground control simulation are discussed.

  13. Collective pairing Hamiltonian in the GCM approximation

    NASA Astrophysics Data System (ADS)

    Góźdź, A.; Pomorski, K.; Brack, M.; Werner, E.

    1985-08-01

    Using the generator coordinate method and the gaussian overlap approximation we derived the collective Schrödinger-type equation starting from a microscopic single-particle plus pairing hamiltonian for one kind of particle. The BCS wave function was used as the generator function. The pairing energy-gap parameter Δ and the gauge transformation anglewere taken as the generator coordinates. Numerical results have been obtained for the full and the mean-field pairing hamiltonians and compared with the cranking estimates. A significant role played by the zero-point energy correction in the collective pairing potential is found. The ground-state energy dependence on the pairing strength agrees very well with the exact solution of the Richardson model for a set of equidistant doubly-degenerate single-particle levels.

  14. Infusion Rate Dependent Pharmacokinetics of Bendamustine with Altered Formation of γ-hydroxybendamustine (M3) Metabolite Following 30- and 60-min Infusion of Bendamustine in Rats.

    PubMed

    Srinivas, N R; Richter, W; Devaraj, V C; Suresh, P S; Bhamdipati, R K; Mullangi, R

    2016-07-01

    Bendamustine is an alkylating agent administered as 1 h intravenous infusion in the clinic for the treatment of malignant haematological cancers. The aim of the study was to evaluate the pharmacokinetics of bendamustine and its key cytochrome P 450 (CYP) 1A2 mediated γ-hydroxybendamustine (M3) metabolite after 30- and 60-min intravenous infusion of bendamustine in rats. 2 groups were assigned to receive bendamustine either as 30- or 60-min infusion and doses were normalized to 15 mg/kg for the sake of statistical evaluation. Serial pharmacokinetic samples were collected and were analysed for the circulatory levels of bendamustine and its M3 metabolite. Standard pharmacokinetic parameters were generated for bendamustine and its M3 metabolite. Regardless of the intravenous regimens, Cmax coincided with end of infusion for both bendamustine and its M3 metabolite. Immediately after stoppage of infusion, a rapid decline in the plasma levels occurred for both bendamustine and M3 metabolite. The Cmax and AUC0-∞ parameters for bendamustine after 60-min infusion were 1.90 and 1.34-fold higher; while CL was lower by 1.32-fold as compared to the 30-min infusion. In contrast, the Cmax and AUC0-∞ after 30-min infusion for the M3 metabolite was 2.15- and 2.78-fold greater; while CL was 2.32-fold lower when compared to the 60-min infusion. However, T1/2 and Vz values were similar between the 2 intravenous treatments for bendamustine or the M3 metabolite. The data unequivocally confirmed the existence of differential pharmacokinetics of bendamustine and its M3 metabolite as the function of the duration of intravenous infusion.

  15. Electron pairing without superconductivity.

    PubMed

    Cheng, Guanglei; Tomczyk, Michelle; Lu, Shicheng; Veazey, Joshua P; Huang, Mengchen; Irvin, Patrick; Ryu, Sangwoo; Lee, Hyungwoo; Eom, Chang-Beom; Hellberg, C Stephen; Levy, Jeremy

    2015-05-14

    Strontium titanate (SrTiO3) is the first and best known superconducting semiconductor. It exhibits an extremely low carrier density threshold for superconductivity, and possesses a phase diagram similar to that of high-temperature superconductors--two factors that suggest an unconventional pairing mechanism. Despite sustained interest for 50 years, direct experimental insight into the nature of electron pairing in SrTiO3 has remained elusive. Here we perform transport experiments with nanowire-based single-electron transistors at the interface between SrTiO3 and a thin layer of lanthanum aluminate, LaAlO3. Electrostatic gating reveals a series of two-electron conductance resonances-paired electron states--that bifurcate above a critical pairing field Bp of about 1-4 tesla, an order of magnitude larger than the superconducting critical magnetic field. For magnetic fields below Bp, these resonances are insensitive to the applied magnetic field; for fields in excess of Bp, the resonances exhibit a linear Zeeman-like energy splitting. Electron pairing is stable at temperatures as high as 900 millikelvin, well above the superconducting transition temperature (about 300 millikelvin). These experiments demonstrate the existence of a robust electronic phase in which electrons pair without forming a superconducting state. Key experimental signatures are captured by a model involving an attractive Hubbard interaction that describes real-space electron pairing as a precursor to superconductivity. PMID:25971511

  16. Electron pairing without superconductivity

    NASA Astrophysics Data System (ADS)

    Levy, Jeremy

    Strontium titanate (SrTiO3) is the first and best known superconducting semiconductor. It exhibits an extremely low carrier density threshold for superconductivity, and possesses a phase diagram similar to that of high-temperature superconductors--two factors that suggest an unconventional pairing mechanism. Despite sustained interest for 50 years, direct experimental insight into the nature of electron pairing in SrTiO3 has remained elusive. Here we perform transport experiments with nanowire-based single-electron transistors at the interface between SrTiO3 and a thin layer of lanthanum aluminate, LaAlO3. Electrostatic gating reveals a series of two-electron conductance resonances--paired electron states--that bifurcate above a critical pairing field Bp of about 1-4 tesla, an order of magnitude larger than the superconducting critical magnetic field. For magnetic fields below Bp, these resonances are insensitive to the applied magnetic field; for fields in excess of Bp, the resonances exhibit a linear Zeeman-like energy splitting. Electron pairing is stable at temperatures as high as 900 millikelvin, well above the superconducting transition temperature (about 300 millikelvin). These experiments demonstrate the existence of a robust electronic phase in which electrons pair without forming a superconducting state. Key experimental signatures are captured by a model involving an attractive Hubbard interaction that describes real-space electron pairing as a precursor to superconductivity. Support from AFOSR, ONR, ARO, NSF, DOE and NSSEFF is gratefully acknowledged.

  17. Drop by drop backscattered signal of a 50 × 50 × 50 m3 volume: A numerical experiment

    NASA Astrophysics Data System (ADS)

    Gires, A.; Tchiguirinskaia, I.; Schertzer, D.

    2016-09-01

    The goal of this paper is to analyse the influence of individual drop positions on a backscattered radar signal. This is achieved through a numerical experiment: a 3D rain drop field generator is developed and implemented over a volume of 50 × 50 × 50 m3, and then the sum of the electromagnetic waves backscattered by its hydrometeors is computed. Finally the temporal evolution over 1 s is modelled with simplistic assumptions. For the rainfall generator, the liquid water content (LWC) distribution is represented with the help of a multiplicative cascade down to 0.5 m, below which it is considered as homogeneous. Within each 0.5 × 0.5 × 0.5 m3 patch, liquid water is distributed into drops, located randomly uniformly according to a pre-defined drop size distribution (DSD). Such configuration is compared with the one consisting of the same drops being uniformly distributed over the entire 50 × 50 × 50 m3 volume. Due to the fact that the radar wave length is much smaller than the size of a rainfall "patch", it appears that, in agreement with the theory, we retrieve an exponential distribution for potential measures on horizontal reflectivity. Much thinner dispersion is noticed for differential reflectivity. We show that a simple ballistic assumption for drop velocities does not enable the reproduction of radar observations, and turbulence should be taken into account. Finally the sensitivity of these outputs to the various model parameters is quantified.

  18. Machining of Christmas tree parts of 06Kh20N8M3D2L corrosion-resistant steel

    SciTech Connect

    Rubinov, S.R.; Balaoglanov, M.M.; Baluyants, E.G.

    1983-09-01

    To address the problem of corrosion cracking, equipment has been developed of 06Kh20N8M3D21 austenitic-ferritic corrosion-resistant multiply alloyed steel. But as this steel is difficult to machine investigations were made to determine the parameters and conditions for machining Christmas tree parts made of this steel. Turning, drilling, thread cutting, and milling are specified. The optimum conditions for machining Christmas tree parts were established in tests. The tests also showed that the coefficient of machinability of the steel is 3 or 4 times less than that of 20KhGSL steel, which is normally used for Christmas tree production.

  19. Image-Subtraction Photometry of the Globular Cluster M3: Identification of New Double-Mode RR Lyrae Stars

    NASA Astrophysics Data System (ADS)

    Clementini, Gisella; Corwin, T. Michael; Carney, Bruce W.; Sumerel, Andrew N.

    2004-02-01

    that double-mode variables are observed to switch their dominant pulsation modes while remaining RRd's. The phenomenon is found to occur in a 1 yr time span, thus suggesting that these stars are undergoing a rapid evolutionary phase and that both redward and blueward evolution may take place among the HB stars in the Oosterhoff type I cluster M3. The unusual behavior of the M3 RRd's is discussed in detail and compared with that of the double-mode RR Lyrae identified so far in globular clusters and in the field of our and other Local Group galaxies. We find a lack of correlation between the presence of RRd variables and any of the cluster structural parameters.

  20. Paired Straight Hearth Furnace

    SciTech Connect

    2009-04-01

    This factsheet describes a research project whose goals are to design, develop, and evaluate the scalability and commercial feasibility of the PSH Paired Straight Hearth Furnace alternative ironmaking process.

  1. Upregulation of M3 muscarinic receptor inhibits cardiac hypertrophy induced by angiotensin II

    PubMed Central

    2013-01-01

    Background M3 muscarinic acetylcholine receptor (M3-mAChR) is stably expressed in the myocardium, but its pathophysiological role remains largely undefined. This study aimed to investigate the role of M3-mAChR in cardiac hypertrophy induced by angiotensin II (Ang II) and elucidate the underlying mechanisms. Methods Cardiac-specific M3-mAChR overexpression transgenic (TG) mice and rat H9c2 cardiomyoblasts with ectopic expression of M3-mAChR were established. Models of cardiac hypertrophy were induced by transverse aortic constriction (TAC) or Ang II infusion in the mice in vivo, and by isoproterenol (ISO) or Ang II treatment of H9c2 cells in vitro. Cardiac hypertrophy was evaluated by electrocardiography (ECG) measurement, hemodynamic measurement and histological analysis. mRNA and protein expression were detected by real-time RT-PCR and Western blot analysis. Results M3-mAChR was upregulated in hypertrophic heart, while M2-mAChR expression did not change significantly. M3-mAChR overexpression significantly attenuated the increased expression of atrial natriuretic peptide and β-myosin heavy chain induced by Ang II both in vivo and in vitro. In addition, M3-mAChR overexpression downregulated AT1 receptor expression and inhibited the activation of MAPK signaling in the heart. Conclusion The upregulation of M3-mAChR during myocardial hypertrophy could relieve the hypertrophic response provoked by Ang II, and the mechanism may involve the inhibition of MAPK signaling through the downregulation of AT1 receptor. PMID:24028210

  2. Pairing theory of high Tc and low Tc superconductors

    NASA Astrophysics Data System (ADS)

    Sang, Boo Nam

    1994-09-01

    New solutions for Tc, the order parameter, and the density of states are obtained, based on the fact that pairs are formed within the pairing interaction range, TD (Debye), via the BCS pairing theory (not the BCS results). They are valiid for all ify = {T D}/{πT c}, and are applicable to low Tc (LTC) and high Tc (HTS) superconductors. The order parameter variation with y is shown to account for all features of HTS. A new density of states via the zero order parameter outside the pairing interaction range is found to account for low energy states observed in HTS. For large y (LTS), the BCS results are reproduced.

  3. Adaptive Pairing Reversible Watermarking.

    PubMed

    Dragoi, Ioan-Catalin; Coltuc, Dinu

    2016-05-01

    This letter revisits the pairwise reversible watermarking scheme of Ou et al., 2013. An adaptive pixel pairing that considers only pixels with similar prediction errors is introduced. This adaptive approach provides an increased number of pixel pairs where both pixels are embedded and decreases the number of shifted pixels. The adaptive pairwise reversible watermarking outperforms the state-of-the-art low embedding bit-rate schemes proposed so far.

  4. M3S: the local network for electric wheelchairs and rehabilitation equipment.

    PubMed

    Linnman, S

    1996-09-01

    M3S is an open electric network standard for connecting rehabilitation equipment, especially electric modules in a wheelchair. It provides bidirectional communication at 250 kbaud via a CAN bus and extra safety lines for "Dead Man's Switch" and a TURN ON key. In an M3S system, the same input device may be used for controlling many different output devices in different operating modes. It provides flexible configuration tools for adapting the system for the individual user. M3S has been demonstrated and tested in more than ten different European development projects.

  5. Cooper Pair Insulators

    NASA Astrophysics Data System (ADS)

    Valles, James

    One of the recent advances in the field of the Superconductor to Insulator Transition (SIT) has been the discovery and characterization of the Cooper Pair Insulator phase. This bosonic insulator, which consists of localized Cooper pairs, exhibits activated transport and a giant magneto-resistance peak. These features differ markedly from the weakly localized transport that emerges as pairs break at a ``fermionic'' SIT. I will describe how our experiments on films nano-patterned with a nearly triangular array of holes have enabled us to 1) distinguish bosonic insulators from fermionic insulators, 2) show that Cooper pairs, rather than quasi-particles dominate the transport in the Cooper Pair insulator phase, 3) demonstrate that very weak, sub nano-meter thickness inhomogeneities control whether a bosonic or fermionic insulator forms at an SIT and 4) reveal that Cooper pairs disintegrate rather than becoming more tightly bound deep in the localized phase. We have also developed a method, using a magnetic field, to tune flux disorder reversibly in these films. I will present our latest results on the influence of magnetic flux disorder and random gauge fields on phenomena near bosonic SITs. This work was performed in collaboration with M. D. Stewart, Jr., Hung Q. Nguyen, Shawna M. Hollen, Jimmy Joy, Xue Zhang, Gustavo Fernandez, Jeffrey Shainline and Jimmy Xu. It was supported by NSF Grants DMR 1307290 and DMR-0907357.

  6. Wall-touching kink mode calculations with the M3D code

    SciTech Connect

    Breslau, J. A. Bhattacharjee, A.

    2015-06-15

    This paper seeks to address a controversy regarding the applicability of the 3D nonlinear extended MHD code M3D [W. Park et al., Phys. Plasmas 6, 1796 (1999)] and similar codes to calculations of the electromagnetic interaction of a disrupting tokamak plasma with the surrounding vessel structures. M3D is applied to a simple test problem involving an external kink mode in an ideal cylindrical plasma, used also by the Disruption Simulation Code (DSC) as a model case for illustrating the nature of transient vessel currents during a major disruption. While comparison of the results with those of the DSC is complicated by effects arising from the higher dimensionality and complexity of M3D, we verify that M3D is capable of reproducing both the correct saturation behavior of the free boundary kink and the “Hiro” currents arising when the kink interacts with a conducting tile surface interior to the ideal wall.

  7. The Distribution and Mineralogy of Anorthosite in the Orientale Basin: New Perspectives from M^3 Data

    NASA Astrophysics Data System (ADS)

    Cheek, L. C.; Donaldson Hanna, K. L.; Pieters, C. M.; Head, J. W.; Whitten, J. L.

    2012-07-01

    A detailed mineralogic analysis of the Orientale Basin using M^3 data reveals that crystalline anorthosite (shocked to <25 GPa) is abundant, and that the most highly pure examples (> ~98% plagioclase) are concentrated in the Inner Rook Mountains.

  8. 27. Naval Facility Engineering Command Drawing 6068752 (463M3) (1975), 'Electrolite ...

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

    27. Naval Facility Engineering Command Drawing 6068752 (463-M-3) (1975), 'Electrolite Aerosol Removal System' - Mare Island Naval Shipyard, Acid Mixing Facility, California Avenue & E Street, Vallejo, Solano County, CA

  9. The Mars Methane Analogue Mission (M3): Results of the 2011 Field Deployment

    NASA Astrophysics Data System (ADS)

    Cloutis, E. A.; Whyte, L.; Qadi, A.; Bell, J. F.; Berard, G.; Boivin, A.; Ellery, A.; Haddad, E.; Jamroz, W.; Kruzelecky, R.; Mann, P.; Olsen, K.; Perrot, M.; Popa, D.; Rhind, T.; Samson, C.; Sharma, R.; Stromberg, J.; Strong, K.; Tremblay, A.; Wilhelm, R.; Wing, B.; Wong, B.

    2012-03-01

    The M3 mission simulated a rover mission to Mars to search for sources of methane. The 2011 campaign found that methane plumes from serpentinite are very localized and target selection based on imagery is preferred over direct methane detection.

  10. Dual GPCR and GAG mimicry by the M3 chemokine decoy receptor

    SciTech Connect

    Alexander-Brett, Jennifer M.; Fremont, Daved H.

    2008-09-23

    Viruses have evolved a myriad of evasion strategies focused on undermining chemokine-mediated immune surveillance, exemplified by the mouse {gamma}-herpesvirus 68 M3 decoy receptor. Crystal structures of M3 in complex with C chemokine ligand 1/lymphotactin and CC chemokine ligand 2/monocyte chemoattractant protein 1 reveal that invariant chemokine features associated with G protein-coupled receptor binding are primarily recognized by the decoy C-terminal domain, whereas the N-terminal domain (NTD) reconfigures to engage divergent basic residue clusters on the surface of chemokines. Favorable electrostatic forces dramatically enhance the association kinetics of chemokine binding by M3, with a primary role ascribed to acidic NTD regions that effectively mimic glycosaminoglycan interactions. Thus, M3 employs two distinct mechanisms of chemical imitation to potently sequester chemokines, thereby inhibiting chemokine receptor binding events as well as the formation of chemotactic gradients necessary for directed leukocyte trafficking.

  11. Transduction of Recombinant M3-p53-R12 Protein Enhances Human Leukemia Cell Apoptosis

    PubMed Central

    Lu, Tsung Chi; Zhao, Guan- Hao; Chen, Yao Yun; Chien, Chia-Ying; Huang, Chi-Hung; Lin, Kwang Hui; Chen, Shen Liang

    2016-01-01

    Tumor suppressor protein p53 plays important roles in initiating cell cycle arrest and promoting tumor cell apoptosis. Previous studies have shown that p53 is either mutated or defective in approximately 50% of human cancers; therefore restoring normal p53 activity in cancer cells might be an effective anticancer therapeutic approach. Herein, we designed a chimeric p53 protein flanked with the MyoD N-terminal transcriptional activation domain (amino acids 1-62, called M3) and a poly-arginine (R12) cell penetrating signal in its N-and C-termini respectively. This chimeric protein, M3-p53-R12, can be expressed in E. coli and purified using immobilized metal ion chromatography followed by serial refolding dialysis. The purified M3-p53-R12 protein retains DNA-binding activity and gains of cell penetrating ability. Using MTT assay, we demonstrated that M3-p53-R12 inhibited the growth of K562, Jurkat as well as HL-60 leukemia cells carrying mutant p53 genes. Results from FACS analysis also demonstrated that transduction of M3-p53-R12 protein induced cell cycle arrest of these leukemia cells. Of special note, M3-p53-R12 has no apoptotic effect on normal mesenchymal stem cells (MSC) and leukocytes, highlighting its differential effects on normal and tumor cells. To sum up, our results reveal that purified recombinant M3-p53-R12 protein has functions of suppressing the leukemia cell lines' proliferation and launching cell apoptosis, suggesting the feasibility of using M3-p53-R12 protein as an anticancer drug. In the future we will test whether this chimeric protein can preferentially trigger the death of malignant cancer cells without affecting normal cells in animals carrying endogenous or xenographic tumors. PMID:27390612

  12. Critical metabolic roles of β-cell M3 muscarinic acetylcholine receptors

    PubMed Central

    de Azua, Inigo Ruiz; Gautam, Dinesh; Jain, Shalini; Guettier, Jean-Marc; Wess, Jürgen

    2013-01-01

    Muscarinic acetylcholine (ACh) receptors (mAChRs; M1–M5) regulate the activity of an extraordinarily large number of important physiological processes. We and others previously demonstrated that pancreatic β-cells are endowed with M3 mAChRs which are linked to G proteins of the Gq family. The activation of these receptors by ACh or other muscarinic agonists leads to the augmentation of glucose-induced insulin release via multiple mechanisms. Interestingly, in humans, ACh acting on human β-cell mAChRs is released from adjacent α-cells which express both choline acetyltransferase (ChAT) and the vesicular acetylcholine transporter (vAChT), indicative of the presence of a non-neuronal cholinergic system in human pancreatic islets. In order to shed light on the physiological roles of β-cell M3 receptors, we recently generated and analyzed various mutant mouse models. Specifically, we carried out studies with mice which overexpressed M3 receptors or mutant M3 receptors in pancreatic β-cells or which selectively lacked M3 receptors or M3-receptor-associated proteins in pancreatic β-cells. Our findings indicate that β-cell M3 receptors play a key role in maintaining proper insulin release and whole body glucose homeostasis and that strategies aimed at enhancing signaling through β-cell M3 receptors may prove useful to improve β-cell function for the treatment of type 2 diabetes (T2D). PMID:22525375

  13. Level of helium enhancement among M3's horizontal branch stars

    NASA Astrophysics Data System (ADS)

    Valcarce, A. A. R.; Catelan, M.; Alonso-García, J.; Contreras Ramos, R.; Alves, S.

    2016-05-01

    other words, the position of an HB star in such a CMD is exactly the same for a given chemical composition for multiple combinations of the parameters Y, MHB, and age along the HB evolutionary track. Other HST UV filters do not appear to be as severely affected by this degeneracy effect, to which visual bandpasses are also immune. On the other hand, such near-UV CMDs can be extremely useful for the hottest stars along the cool BHB end. Conclusions: Based on a reanalysis of the distribution of HB stars in the y vs. (b - y) plane, we find that the coolest BHB stars in M3 (i.e., those with Teff< 8300 K) are very likely enhanced in helium by ΔY ≈ 0.01, compared with the red HB stars in the same cluster. Using near-UV HST photometry, on the other hand, we find evidence of a progressive increase in Y with increasing temperature, reaching ΔY ≈ 0.02 at Teff ≈ 10 900 K.

  14. Identification and molecular characterization of the cDNA encoding Cucumis melo allergen, Cuc m 3, a plant pathogenesis-related protein

    PubMed Central

    Sankian, Mojtaba; Hajavi, Jafar; Moghadam, Malihe; Varasteh, Abdol-Reza

    2014-01-01

    Background: Melon (Cucumis melo) allergy is one of the most common food allergies, characterized by oral allergy syndrome. To date, two allergen molecules, Cuc m 1 and Cuc m 2, have been fully characterized in melon pulp, but there are few reports about the molecular characteristics of Cuc m 3. Methods: The Cuc m 3 cDNA has been characterized by rapid amplification of cDNA ends (RACE), which revealed a 456 base-pair (bp) fragment encoding a 151-amino acid polypeptide with a predicted molecular mass of 16.97 kDa, and identified 79 and 178 bp untranslated sequences at the 5′ and 3´ ends, respectively. Results: In silico analysis showed strong similarities between Cuc m 3 and other plant pathogen-related protein 1s from cucumber, grape, bell pepper, and tomato. Conclusion: Here we report the identification and characterization of the Cuc m 3 cDNA, which will be utilized for further analyses of structural and allergenic features of this allergen. PMID:26989726

  15. Isolation and characterization of rabbit anti-m3 2,2,7G antibodies.

    PubMed

    Luhrmann, R; Appel, B; Bringmann, P; Rinke, J; Reuter, R; Rothe, S; Bald, R

    1982-11-25

    Antibodies specific for intact 2,2,7-trimethylguanosine (m3 2,2,7G) were induced by immunization of rabbits with a nucleoside-human serum albumen (HSA) conjugate. Competition radioimmunoassay showed that the antibody distinguishes well between intact m3 2,2,7G and its alkali-hydrolysed form (m3 2,2,7G*). Antibody specificity is largely dependent on the presence of all three methyl groups in m3 2,2,7G: none of the less extensively methylated nucleosides m7G, m2G and m2 2,2G is able to compete efficiently with the homologous hapten. Little or no competition was observed with m1G, m1A, m6A, m5U and each of the four unmodified ribonucleosides. Binding studies with nucleoplasmic RNAs from Ehrlich ascites cells suggest that the antibody reacts specifically with the m3 2,2,7G-containing cap structure of the small nuclear U-RNAs (U-snRNAs). Thus the antibody should be a valuable tool for studying the role of the 5'-terminal regions of the U-snRNAs of eucaryotic cells. PMID:7155893

  16. Dihydropyridines' metabolites-induced early apoptosis after myocardial infarction in rats; new outlook on preclinical study with M-2 and M-3.

    PubMed

    Mitręga, Katarzyna A; Nożyński, Jerzy; Porc, Maurycy; Spałek, Adrianna M; Krzemiński, Tadeusz F

    2016-02-01

    Our previous studies established cardio-protective effects of furnidipine and its active metabolites called M-2 and M-3. The aim of current research was to compare the effects of single oral pretreatment with 20 mg kg(-1) of M-2 and M-3 on mortality, different forms of arrhythmias, blood pressures parameters and ST-segment changes during occlusion (for 90 min) and reperfusion in the model of myocardial infarction in rats evoked by left anterior descending coronary artery occlusion. Additionally, the development of programmed cell death and biochemical parameters in blood serum were studied at 4th day after infarction. Furnidipines' metabolites effectively reduced mortality index while did not markedly influence on blood pressures parameters, arrhythmias, ST-segment changes as well as biochemical parameters. Intriguingly, programmed cell death study (TUNEL) showed distinct increase in the amount of apoptotic nuclei in post-infarcted myocardium, granulation tissue and what is more in arteriolar walls after M-2 and M-3 application. Moreover, M-2 turned out to be more powerful in stimulation of apoptosis in granulation tissue surrounding infarcted area whereas M-3 presented balanced profile in this matter. Taking into account that programmed cell death plays positive role in post-infarcted heart healing, M-2 presents itself as more attractive agent for oral pretreatment in early stages of ischemia by non-stable individuals due to its more specific action in stimulation repairing processes in granulation tissue as well as in arteriolar walls. While M-2 and M-3 are common metabolites present in degradation pathways of many widely used dihydropyridines in clinic, this key fact put the new outlook on understanding additional mechanism and effects of not only furnidipines' metabolites but also other dihydropyridines.

  17. Multi-pair states in electron-positron pair creation

    NASA Astrophysics Data System (ADS)

    Wöllert, Anton; Bauke, Heiko; Keitel, Christoph H.

    2016-09-01

    Ultra strong electromagnetic fields can lead to spontaneous creation of single or multiple electron-positron pairs. A quantum field theoretical treatment of the pair creation process combined with numerical methods provides a description of the fermionic quantum field state, from which all observables of the multiple electron-positron pairs can be inferred. This allows to study the complex multi-particle dynamics of electron-positron pair creation in-depth, including multi-pair statistics as well as momentum distributions and spin. To illustrate the potential benefit of this approach, it is applied to the intermediate regime of pair creation between nonperturbative Schwinger pair creation and perturbative multiphoton pair creation where the creation of multi-pair states becomes nonnegligible but cascades do not yet set in. Furthermore, it is demonstrated how spin and helicity of the created electrons and positrons are affected by the polarization of the counterpropagating laser fields, which induce the creation of electron-positron pairs.

  18. Stability and size of particle pairs in complex plasmas

    SciTech Connect

    Nosenko, V.; Ivlev, A. V.; Kompaneets, R.; Morfill, G.

    2014-11-15

    Particle pairing in a complex plasma was experimentally studied with the emphasis on pair spatial extent and stability. Micron-size particles were suspended in the (pre)sheath area above the lower electrode in a capacitively coupled radio-frequency discharge in argon. They formed vertical pairs due to the ion wakes created by the flow of ions past particles. We discuss the confinement mechanism for the lower particle, resulting from a combination of the wake field and the field of non-uniform sheath. A model of particle pairs is proposed, which provides good description for the dependence of pair size and stability on experimental parameters.

  19. NMR analysis of base-pair opening kinetics in DNA.

    PubMed

    Szulik, Marta W; Voehler, Markus; Stone, Michael P

    2014-12-12

    Base pairing in nucleic acids plays a crucial role in their structure and function. Differences in the base-pair opening and closing kinetics of individual double-stranded DNA sequences or between chemically modified base pairs provide insight into the recognition of these base pairs by DNA processing enzymes. This unit describes how to quantify the kinetics for localized base pairs by observing changes in the imino proton signals by nuclear magnetic resonance spectroscopy. The determination of all relevant parameters using state-of-the art techniques and NMR instrumentation, including cryoprobes, is discussed.

  20. Strong pairing approximation in comparison with the exact solutions to the pairing Hamiltonian

    NASA Astrophysics Data System (ADS)

    Lunyov, A. V.; Mikhajlov, V. M.

    2016-01-01

    Results of the Strong Pairing Approximation (SPA) as a method with the exact particle number conservation are compared with those of the quasiparticle method (QM). It is shown that SPA comes to the same equations as QM for the gap parameter, chemical potential and one- and two-quasiparticle states. Calculations are performed for 14864Gd84 as an example, and compared with the exact solutions to the pairing Hamiltonian.

  1. A Discussion of the High Energy Density Primary Battery Employed in the FOTON M3 Mission

    NASA Astrophysics Data System (ADS)

    Bennetti, A.; Reece, D.; Spurrett, R.; Schautz, M.; Green, K.

    2008-09-01

    In 2005, ABSL Space Products (ABSL) was contracted by QinetiQ to deliver the lithium sulfuryl chloride primary battery system for the FOTON M3 ESA (European Space Agency) mission. FOTON M3 was led by the ESA Directorate of Human Spaceflight & Exploration and carried a number of materials science, fluid physics and biology experiments as well as technology demonstration payloads. A number of the experiments required a very high energy density primary battery power source. This battery was manufactured by ABSL, and the mission was successfully completed in September 2007 following a twelve days orbiting in Low Earth Orbit (LEO).

  2. Development of RT-components for the M-3 Strawberry Harvesting Robot

    NASA Astrophysics Data System (ADS)

    Yamashita, Tomoki; Tanaka, Motomasa; Yamamoto, Satoshi; Hayashi, Shigehiko; Saito, Sadafumi; Sugano, Shigeki

    We are now developing the strawberry harvest robot called “M-3” prototype robot system under the 4th urgent project of MAFF. In order to develop the control software of the M-3 robot more efficiently, we innovated the RT-middleware “OpenRTM-aist” software platform. In this system, we developed 9 kind of RT-Components (RTC): Robot task sequence player RTC, Proxy RTC for image processing software, DC motor controller RTC, Arm kinematics RTC, and so on. In this paper, we discuss advantages of RT-middleware developing system and problems about operating the RTC-configured robotic system by end-users.

  3. Probing the tides in interacting galaxy pairs

    NASA Technical Reports Server (NTRS)

    Borne, Kirk D.

    1990-01-01

    Detailed spectroscopic and imaging observations of colliding elliptical galaxies revealed unmistakable diagnostic signatures of the tidal interactions. It is possible to compare both the distorted luminosity distributions and the disturbed internal rotation profiles with numerical simulations in order to model the strength of the tidal gravitational field acting within a given pair of galaxies. Using the best-fit numerical model, one can then measure directly the mass of a specific interacting binary system. This technique applies to individual pairs and therefore complements the classical methods of measuring the masses of galaxy pairs in well-defined statistical samples. The 'personalized' modeling of galaxy pairs also permits the derivation of each binary's orbit, spatial orientation, and interaction timescale. Similarly, one can probe the tides in less-detailed observations of disturbed galaxies in order to estimate some of the physical parameters for larger samples of interacting galaxy pairs. These parameters are useful inputs to the more universal problems of (1) the galaxy merger rate, (2) the strength and duration of the driving forces behind tidally stimulated phenomena (e.g., starbursts and maybe quasi steller objects), and (3) the identification of long-lived signatures of interaction/merger events.

  4. Seeing the Moon In a New Light: Educational Resources Developed in Association with M3

    NASA Astrophysics Data System (ADS)

    Runyon, C. J.; Shupla, C.; Shipp, S. S.; Hallau, K.; Boyce, K.; Pieters, C. M.

    2009-12-01

    M3 is a high spatial and spectral resolution spectrometer designed to help scientists better understand the compositional variation of the Moon’s surface. Flown on India’s first spacecraft to the Moon, Chandrayaan-1, M3 collected over 4.6 billion spectra! To facilitate student awareness and understanding of these data and resulting imagery, our team co-sponsors an on-line course, Geology of the Moon, for pre- and in-service teachers through Montana State University and has generated an educator guide: Seeing the Moon: Using Light to Investigate the Moon. This guide is a series of educational inquiry-based and hands-on activity modules created in support of the M3 science. In these modules, students investigate the physics of light and the geologic history of the Moon. Through these dynamic activities, 5th to 8th grade students experiment with light and color; collect and analyze authentic spectral data from rock samples using an ALTA hand-held reflectance spectrometer; map the rock types of the Moon; and develop theories of the Moon's history. M3 classroom loaner kits that include a lunar globe, rock samples, sets of the ALTA reflectance spectrometers, and more are available upon request.

  5. Foton-M3 Unmanned Russian Research Satellite- Development, Implementation and Operations

    NASA Astrophysics Data System (ADS)

    Ilyin, Eugene A.; Skidmore, Michael G.

    2008-06-01

    The Foton-M3 spacecraft launched from Baikonur Cosmodrome (Kazakhstan) on 14 September 2007 and landed 12 days later approximately 130 km south of Kustanay, Northern Kazakhstan. Following the successful National Aeronautics and Space Administration (NASA) and Institute for Biomedical Problems (IMBP) collaboration on the Russian Foton-M2 spaceflight (June 2005), IMBP invited NASA to continue and broaden its participation in four Russian biomedical studies on the Foton-M3 spaceflight. Where the Foton-M2 collaboration had been accomplished without an exchange of funds, the basis for the ongoing bilateral interaction on Foton-M3 was both a cooperative Space Act Agreement and a NASA contract with IMBP. As in Foton-M2, NASA scientists agreed to focus their efforts on research that would be complementary and would facilitate the accomplishment of the original Russian science goals. Foton-M3 hardware enhancements included NASA inserts installed in the IMBP flight hardware to provide programmable in-flight video recording for newts and geckos, drinking water for the geckos, and a preflight "shower" of Bromodeoxyuridine (BrdU) for the newts.

  6. Divergent evolution of the M3A family of metallopeptidases in plants.

    PubMed

    Kmiec, Beata; Teixeira, Pedro F; Murcha, Monika W; Glaser, Elzbieta

    2016-07-01

    Plants, as stationary organisms, have developed mechanisms allowing them efficient resource reallocation and a response to changing environmental conditions. One of these mechanisms is proteome remodeling via a broad peptidase network present in various cellular compartments including mitochondria and chloroplasts. The genome of the model plant Arabidopsis thaliana encodes as many as 616 putative peptidase-coding genes organized in 55 peptidase families. In this study, we describe the M3A family of peptidases, which comprises four members: mitochondrial and chloroplastic oligopeptidase (OOP), cytosolic oligopeptidase (CyOP), mitochondrial octapeptidyl aminopeptidase 1 (Oct1) and plant-specific protein of M3 family (PSPM3) of unknown function. We have analyzed the evolutionary conservation of M3A peptidases across plant species and the functional specialization of the three distinct subfamilies. We found that the subfamily-containing OOP and CyOP-like peptidases, responsible for oligopeptide degradation in the endosymbiotic organelles (OOP) or in the cytosol (CyOP), are highly conserved in all kingdoms of life. The Oct1-like peptidase subfamily involved in pre-protein maturation in mitochondria is conserved in all eukaryotes, whereas the PSPM3-like protein subfamily is strictly conserved in higher plants only and is of unknown function. Specific characteristics within PSPM3 sequences, i.e. occurrence of a N-terminal transmembrane domain and amino acid changes in distal substrate-binding motif, distinguish PSPM3 proteins from other members of M3A family. We performed peptidase activity measurements to analyze the role of substrate-binding residues in the different Arabidopsis M3A paralogs. PMID:27100569

  7. Breaking of Cooper pairs in 108Pd

    NASA Astrophysics Data System (ADS)

    Rahmatinejad, A.; Kakavand, T.; Razavi, R.

    2016-04-01

    In this paper, breaking of Cooper pairs in 108Pd is investigated within the canonical ensemble framework and the BCS model. Our results show an evidence of two phase transitions, which are related to neutron and proton systems. Also, with consideration of pairing interaction, the role of neutron and proton systems in entropy, spin cutoff parameter and as a result in the moment of inertia are investigated. The results show minor role for the proton system at low temperatures and approximately equal roles for both neutron and proton systems after the critical temperature. Good agreement was observed between obtained results and the experimental data.

  8. Reactor performance of a 750 m(3) anaerobic digestion plant: varied substrate input conditions impacting methanogenic community.

    PubMed

    Wagner, Andreas Otto; Malin, Cornelia; Lins, Philipp; Gstraunthaler, Gudrun; Illmer, Paul

    2014-10-01

    A 750 m(3) anaerobic digester was studied over a half year period including a shift from good reactor performance to a reduced one. Various abiotic parameters like volatile fatty acids (VFA) (formic-, acetic-, propionic-, (iso-)butyric-, (iso-)valeric-, lactic acid), total C, total N, NH4 -N, and total proteins, as well as the organic matter content and dry mass were determined. In addition several process parameters such as temperature, pH, retention time and input of substrate and the concentrations of CH4, H2, CO2 and H2S within the reactor were monitored continuously. The present study aimed at the investigation of the abundance of acetogens and total cell numbers and the microbial methanogenic community as derived from PCR-dHPLC analysis in order to put it into context with the determined abiotic parameters. An influence of substrate quantity on the efficiency of the anaerobic digestion process was found as well as a shift from a hydrogenotrophic in times of good reactor performance towards an acetoclastic dominated methanogenic community in times of reduced reactor performance. After the change in substrate conditions it took the methano-archaeal community about 5-6 weeks to be affected but then changes occurred quickly.

  9. Existence of best proximity pairs and equilibrium pairs

    NASA Astrophysics Data System (ADS)

    Kim, Won Kyu; Lee, Kyoung Hee

    2006-04-01

    In this paper, using the fixed point theorem for Kakutani factorizable multifunctions, we shall prove new existence theorems of best proximity pairs and equilibrium pairs for free abstract economies, which include the previous fixed point theorems and equilibrium existence theorems.

  10. M3S-based electrical wheelchair with head-controlled device.

    PubMed

    Chen, Show-Hong; Chen, Yu-Luen; Kuo, Te-Son; Chu, Chiung-Yu; Hung, Chao-Nan

    2006-01-01

    The motivation of this research is to improve the ability of ambulation for people with a certain degree of disability. The control of the wheelchair is using two tilt sensors as an input-controlling module. One of the tilt sensors detects the anterior/posterior tilting of the head and moves the wheelchair forward/backward, the other distinguishes the left/right swing of the head. In order to increase the safety of this system, the M3S protocol established by the European Commission is also applied to this research. The system based on M3S protocol has the advantage of real-time signal transmission and emergent status monitoring for SCI patients with C2-C4 level. PMID:17946659

  11. A supersoft variable low-luminosity X-ray source in the globular cluster M3

    NASA Technical Reports Server (NTRS)

    Hertz, P.; Grindlay, J. E.; Bailyn, C. D.

    1993-01-01

    The globular cluster M3 (NGC 5272) was observed twice with the ROSAT high-resolution imager in order to study the low-luminosity X-ray source 1E 1339.8 + 2837. In 1992 January 1E 1339.8 + 2837 had an X-ray luminosity of 2 x 10 exp 35 ergs/s over an order of magnitude brighter than it was when observed with the Einstein Observatory. The source was unresolved and very soft; such supersoft outbursts would be difficult to detect in the vast majority of globular clusters which are more heavily absorbed than M3. In 1992 June the source was too faint to be detected. The soft outburst luminosity and the blackbody radius suggest that 1E 1339.8 + 2837 is a cataclysmic variable in which much of the luminosity is generated by steady nuclear burning of accreted material on the surface of the white dwarf primary.

  12. The M3A multi-sensor buoy network of the Mediterranean Sea

    NASA Astrophysics Data System (ADS)

    Nittis, K.; Tziavos, C.; Bozzano, R.; Cardin, V.; Thanos, Y.; Petihakis, G.; Schiano, M. E.; Zanon, F.

    2007-05-01

    A network of three multi-sensor timeseries stations able to deliver real time physical and biochemical observations of the upper thermocline has been developed for the needs of the Mediterranean Forecasting System during the MFSTEP project. They follow the experience of the prototype M3A system that was developed during the MFSPP project and has been tested during a pilot pre-operational period of 22 months (2000-2001). The systems integrate sensors for physical (temperature, salinity, turbidity, current speed and direction) as well as optical and chemical observations (dissolved oxygen, chlorophyll-a, PAR, nitrate). The south Aegean system (E1-M3A) follows a modular design using independent mooring lines and collects biochemical data in the upper 100 m and physical data in the upper 500 m of the water column. The south Adriatic buoy system (E2-M3A) uses similar instrumentation but on a single mooring line and also tests a new method of pumping water samples from relatively deep layers, performing analysis in the protected "dry" environment of the buoy interior. The Ligurian Sea system (W1-M3A) is an ideal platform for air-sea interaction processes since it hosts a large number of meteorological sensors while its ocean instrumentation, with real time transmission capabilities, is confined in the upper 50 m layer. Despite their different architecture, the three systems have common sampling strategy, quality control and data management procedures. The network operates in the Mediterranean Sea since autumn 2004 collecting timeseries data for calibration and validation of the forecasting system as well for process studies of regional dynamics.

  13. The M3A multi-sensor buoy network of the Mediterranean Sea

    NASA Astrophysics Data System (ADS)

    Nittis, K.; Tziavos, C.; Bozzano, R.; Cardin, V.; Thanos, Y.; Petihakis, G.; Schiano, M. E.; Zanon, F.

    2006-08-01

    A network of three multi-sensor timeseries stations able to deliver real time physical and biochemical observations of the upper thermocline has been developed for the needs of the Mediterranean Forecasting System during the MFSTEP project. They follow the experience of the prototype M3A system that was developed during the MFSPP project and has been tested during a pilot pre-operational period of 22 months (2000-2001). The systems integrate sensors for physical (temperature, salinity, turbidity, current speed and direction) as well as optical and chemical observations (dissolved oxygen, chlorophyll-a, PAR, nitrate). The south Aegean system (E1-M3A) follows a modular design using independent mooring lines and collects biochemical data in the upper 100 m and physical data in the upper 500 m of the water column. The south Adriatic buoy system (E2-M3A) uses similar instrumentation but on a single mooring line and also tests a new method of pumping water samples from relatively deep layers, performing analysis in the protected ''dry'' environment of the buoy interior. The Ligurian Sea system (W1-M3A) is an ideal platform for air-sea interaction processes since it hosts a large number of meteorological sensors while its ocean instrumentation, with real time transmission capabilities, is confined in the upper 50 m layer. Despite their different architecture, the three systems have common sampling strategy, quality control and data management procedures. The network operates in the Mediterranean Sea since autumn 2004 collecting timeseries data for calibration and validation of the forecasting system as well for process studies of regional dynamics.

  14. Contractions of the mouse prostate elicited by acetylcholine are mediated by M(3) muscarinic receptors.

    PubMed

    White, Carl W; Short, Jennifer L; Haynes, John M; Matsui, Minoru; Ventura, Sabatino

    2011-12-01

    Increased smooth muscle tone in the human prostate contributes to the symptoms associated with benign prostatic hyperplasia. In the mouse prostate gland, cholinergic innervation is responsible for a component of the nerve-mediated contractile response. This study investigates the muscarinic receptor subtype responsible for the cholinergic contractile response in the mouse prostate gland. To characterize the muscarinic receptor subtype, mouse prostates taken from wild-type or M(3) muscarinic receptor knockout mice were mounted in organ baths. The isometric force that tissues developed in response to electrical-field stimulation or exogenously applied cholinergic agonists in the presence or absence of a range of muscarinic receptor antagonists was evaluated. Carbachol elicited reproducible and concentration-dependent contractions of the isolated mouse prostate, which were antagonized by the presence of muscarinic receptor antagonists. Calculation of antagonist affinities (pA(2) values) indicated a rank order of antagonist potencies in the mouse prostate of: darifenacin (9.08) = atropine (9.07) = 1,1-dimethyl-4-diphenylacetoxypiperidinium iodide (9.02) > cyclohexyl-hydroxy-phenyl-(3-piperidin-1-ylpropyl)silane (7.85) > cyclohexyl-(4-fluorophenyl)-hydroxy-(3-piperidin-1-ylpropyl)silane (7.39) > himbacine (7.19) > pirenzipine (6.88) > methoctramine (6.20). Furthermore, genetic deletion of the M(3) muscarinic receptor inhibited prostatic contractions to electrical-field stimulation or exogenous administration of acetylcholine. In this study we identified that the cholinergic component of contraction in the mouse prostate is mediated by the M(3) muscarinic receptor subtype. Pharmacological antagonism of the M(3) muscarinic receptor may be a beneficial additional target for the treatment of benign prostatic hyperplasia in the human prostate gland.

  15. Ten-m3 Is Required for the Development of Topography in the Ipsilateral Retinocollicular Pathway

    PubMed Central

    Dharmaratne, Nuwan; Glendining, Kelly A.; Young, Timothy R.; Tran, Heidi; Sawatari, Atomu; Leamey, Catherine A.

    2012-01-01

    Background The alignment of ipsilaterally and contralaterally projecting retinal axons that view the same part of visual space is fundamental to binocular vision. While much progress has been made regarding the mechanisms which regulate contralateral topography, very little is known of the mechanisms which regulate the mapping of ipsilateral axons such that they align with their contralateral counterparts. Results Using the advantageous model provided by the mouse retinocollicular pathway, we have performed anterograde tracing experiments which demonstrate that ipsilateral retinal axons begin to form terminal zones (TZs) in the superior colliculus (SC), within the first few postnatal days. These appear mature by postnatal day 11. Importantly, TZs formed by ipsilaterally-projecting retinal axons are spatially offset from those of contralaterally-projecting axons arising from the same retinotopic location from the outset. This pattern is consistent with that required for adult visuotopy. We further demonstrate that a member of the Ten-m/Odz/Teneurin family of homophilic transmembrane glycoproteins, Ten-m3, is an essential regulator of ipsilateral retinocollicular topography. Ten-m3 mRNA is expressed in a high-medial to low-lateral gradient in the developing SC. This corresponds topographically with its high-ventral to low-dorsal retinal gradient. In Ten-m3 knockout mice, contralateral ventrotemporal axons appropriately target rostromedial SC, whereas ipsilateral axons exhibit dramatic targeting errors along both the mediolateral and rostrocaudal axes of the SC, with a caudal shift of the primary TZ, as well as the formation of secondary, caudolaterally displaced TZs. In addition to these dramatic ipsilateral-specific mapping errors, both contralateral and ipsilateral retinocollicular TZs exhibit more subtle changes in morphology. Conclusions We conclude that important aspects of adult visuotopy are established via the differential sensitivity of ipsilateral and

  16. Aluminum-air power cell: The M3-3 experiment

    NASA Astrophysics Data System (ADS)

    Maimoni, A.; Muelder, S. A.

    1985-03-01

    The M3-3 experiment was a test of the M3 cell coupled to a crystallizer and hydrocyclone for separation of coarse solids before return of electrolyte to the cell. It was essentially a repeat of the M3-2 experiment, but with increased emphasis to understand the sources of experimental error and the evolution of the particle size distributions during the course of the experiment. A new hydrocyclone, scaled to operation with 1 to 5 cells, was tested in conjunction with peristaltic pumps. The test ran at 14 A for 101 min, followed by 122 A for 269 min at 60 C. The main operational problem was failure of the rubber tubing in the peristaltic pump feeding the hydrocyclone. Primary results include reasonable agreement in the material balances and with the calculated crystallization rates, the 50% cut point of the new hydrocyclone at about 8 (MU)m, and the aluminate concentration decreased from 2.4 M to 1.4 M in 21 h at 30 C in a subsequent batch crystallization experiment. The particle size distributions do not change significantly on aging de-ionized water.

  17. MHD Simulations of Spherical Tori and Compact Stellarators Using M3D

    NASA Astrophysics Data System (ADS)

    Strauss, H. R.; Park, W.; Tang, X.; Fu, G. Y.; Sugiyama, L.

    1999-11-01

    The M3D++ unstructured mesh version of the M3D code is being applied to low aspect ratio spherical torus disruption simulations. In addition to spherical tokamaks (ST), similar to NSTX, we also study spherical pinches (SP). It is possible to produce SP equilibria with 1 > q > 1/2, and toroidal current decreasing to zero at the wall. These SP equilibria have reverse magnetic shear except in a narrow layer near the wall. The equilibria are free of the global m=1 modes that plague low q pinches such as RFPs. However there can be unstable (m,n) = (2,3) modes. The M3D++ code has been extended to have the capability of using a 3D mesh in configuration space, suitable for stellarator equilibrium, stability, and nonlinear studies, including resistive effects. Equilibria can be initialized with VMEC output or generated from initial data. Applications to compact stellarator configurations such as the PPPL quasi axisymmetric design will be presented.

  18. The Moon Mineralogy (M3) Imaging Spectrometer: Early Assessment of the Spectral, Radiometric, Spatial and Uniformity Properties

    NASA Technical Reports Server (NTRS)

    Green, Robert O.; Pieters, C. M.; Boardman, J.; Barr, D.; Bruce, C.; Bousman, J.; Chatterjee, A.; Eastwood, M.; Essandoh, V.; Geier, S.; Glavich, T.; Green, R.; Haemmerle, V.; Hyman, S.; Hovland, L.; Koch, T.; Lee, K.; Lundeen, S.; Motts, E.; Mouroulis, P.; Paulson, S.; Plourde, K.; Racho, C.; Robinson, D.; Rodriquez, J.

    2009-01-01

    The Moon Mineralogy Mapper's (M3) is a high uniformity and high signal-to-noise ratio NASA imaging spectrometer that is a guest instrument on the Indian Chandrayaan-1 Mission to the Moon. The laboratory measured spectral, radiometric, spatial, and uniformity characteristics of the M3 instrument are given. The M3 imaging spectrometer takes advantage of a suite of critical enabling capabilities to achieve its measurement requirement with a mass of 8 kg, power usage of 15 W, and volume of 25X18X12 cm. The M3 detector and spectrometer are cooled by a multi-stage passive cooler. This paper presents early M3 performance assessment results.

  19. M3 spectral analysis of lunar swirls and the link between optical maturation and surface hydroxyl formation at magnetic anomalies

    USGS Publications Warehouse

    Kramer, G.Y.; Besse, S.; Dhingra, D.; Nettles, J.; Klima, R.; Garrick-Bethell, I.; Clark, R.N.; Combe, J.-P.; Head, J. W.; Taylor, L.A.; Pieters, C.M.; Boardman, J.; McCord, T.B.

    2011-01-01

    We examined the lunar swirls using data from the Moon Mineralogy Mapper (M3). The improved spectral and spatial resolution of M3 over previous spectral imaging data facilitates distinction of subtle spectral differences, and provides new information about the nature of these enigmatic features. We characterized spectral features of the swirls, interswirl regions (dark lanes), and surrounding terrain for each of three focus regions: Reiner Gamma, Gerasimovich, and Mare Ingenii. We used Principle Component Analysis to identify spectrally distinct surfaces at each focus region, and characterize the spectral features that distinguish them. We compared spectra from small, recent impact craters with the mature soils into which they penetrated to examine differences in maturation trends on- and off-swirl. Fresh, on-swirl crater spectra are higher albedo, exhibit a wider range in albedos and have well-preserved mafic absorption features compared with fresh off-swirl craters. Albedoand mafic absorptions are still evident in undisturbed, on-swirl surface soils, suggesting the maturation process is retarded. The spectral continuum is more concave compared with off-swirl spectra; a result of the limited spectral reddening being mostly constrained to wavelengths less than ???1500 nm. Off-swirl spectra show very little reddening or change in continuum shape across the entire M3 spectral range. Off-swirl spectra are dark, have attenuated absorption features, and the narrow range in off-swirl albedos suggests off-swirl regions mature rapidly. Spectral parameter maps depicting the relative OH surface abundance for each of our three swirl focus regions were created using the depth of the hydroxyl absorption feature at 2.82 ??m. For each of the studied regions, the 2.82 ??m absorption feature is significantly weaker on-swirl than off-swirl, indicating the swirls are depleted in OH relative to their surroundings. The spectral characteristics of the swirls and adjacent terrains from

  20. Pyroxene-type compounds NaM3+Ge2O6, with M = Ga, Mn, Sc and In.

    PubMed

    Redhammer, Günther J; Tippelt, Gerold

    2014-09-01

    The four title compounds, namely sodium gallium germanate, NaGaGe2O6, sodium manganese vanadate germanate, NaMnV0.1Ge1.9O6, sodium scandium germanate, NaScGe2O6, and sodium indium germanate, NaInGe2O6, adopt the high-temperature structure of the pyroxene-type chain germanates, with monoclinic symmetry and space group C2/c. The lattice parameters, the individual and average bond lengths involving M1, and the distortion parameters scale well with the ionic radius of the M1 cation. NaGaGe2O6 has more distorted M1 sites and more extended tetrahedral chains than NaInGe2O6, in which a high degree of kinking is required to maintain the connection between the octahedral and tetrahedral building units of the pyroxene structure. An exceptional case is NaMnGe2O6, in which the strong Jahn-Teller effect of Mn(3+) results in more distorted octahedral sites than expected according to linear extrapolation from the other NaM(3+)Ge2O6 pyroxenes. In contrast with the literature, minor incorporations of V(5+) in the tetrahedral site and a corresponding reduction of Mn(3+) to Mn(2+) in the octahedral sites in the present sample lower the Jahn-Teller distortion and stabilize the Mn-bearing pyroxene, even allowing its synthesis at ambient pressure. PMID:25186356

  1. Dynamics of a vortex pair in radial flow

    SciTech Connect

    Bannikova, E. Yu. Kontorovich, V. M. Reznik, G. M.

    2007-10-15

    The problem of vortex pair motion in two-dimensional radial flow is solved. Under certain conditions for flow parameters, the vortex pair can reverse its motion within a bounded region. The vortex-pair translational velocity decreases or increases after passing through the source/sink region, depending on whether the flow is diverging or converging, respectively. The rotational motion of a corotating vortex pair in a quiescent environment transforms into motion along a logarithmic spiral in radial flow. The problem may have applications in astrophysics and geophysics.

  2. Schwinger pair production with ultracold atoms

    NASA Astrophysics Data System (ADS)

    Kasper, V.; Hebenstreit, F.; Oberthaler, M. K.; Berges, J.

    2016-09-01

    We consider a system of ultracold atoms in an optical lattice as a quantum simulator for electron-positron pair production in quantum electrodynamics (QED). For a setup in one spatial dimension, we investigate the nonequilibrium phenomenon of pair production including the backreaction leading to plasma oscillations. Unlike previous investigations on quantum link models, we focus on the infinite-dimensional Hilbert space of QED and show that it may be well approximated by experiments employing Bose-Einstein condensates interacting with fermionic atoms. Numerical calculations based on functional integral techniques give a unique access to the physical parameters required to realize QED phenomena in a cold atom experiment. In particular, we use our approach to consider quantum link models in a yet unexplored parameter regime and give bounds for their ability to capture essential features of the physics. The results suggest a paradigmatic change towards realizations using coherent many-body states for quantum simulations of high-energy particle physics phenomena.

  3. Multiprocessor switch with selective pairing

    DOEpatents

    Gara, Alan; Gschwind, Michael K; Salapura, Valentina

    2014-03-11

    System, method and computer program product for a multiprocessing system to offer selective pairing of processor cores for increased processing reliability. A selective pairing facility is provided that selectively connects, i.e., pairs, multiple microprocessor or processor cores to provide one highly reliable thread (or thread group). Each paired microprocessor or processor cores that provide one highly reliable thread for high-reliability connect with a system components such as a memory "nest" (or memory hierarchy), an optional system controller, and optional interrupt controller, optional I/O or peripheral devices, etc. The memory nest is attached to a selective pairing facility via a switch or a bus

  4. Prospective very young asteroid pairs

    NASA Astrophysics Data System (ADS)

    Galád, A.; Vokrouhlický, D.; Zizka, J.

    2014-07-01

    Several tens of asteroid pairs can be discerned from the background main-belt asteroids. The majority of them are thought to have formed within only the last few 10^6 yr. The youngest recognized pairs have formed more than ≈ 10 kyr ago. As some details of pair formation are still not understood well, the study of young pairs is of great importance. It is mainly because the conditions at the time of the pair formation could be deduced much more reliably for young pairs. For example, space weathering on the surfaces of the components, or changes in their rotational properties (in spin rates, tumbling, coordinates of rotational pole) could be negligible since the formation of young pairs. Also, possible strong perturbations by main-belt bodies on pair formation can be reliably studied only for extremely young pairs. Some pairs can quickly blend in with the background asteroids, so even the frequency of asteroid pair formation could be determined more reliably based on young pairs (though only after a statistically significant sample is at disposal). In our regular search for young pairs in the growing asteroid database, only multiopposition asteroids with very similar orbital and proper elements are investigated. Every pair component is represented by a number of clones within orbital uncertainties and drifting in semimajor axis due to the Yarkovsky effect. We found that, if the previously unrecognized pairs (87887) 2000 SS_{286} - 2002 AT_{49} and (355258) 2007 LY_{4} - 2013AF_{40} formed at the recent very close approach of their components, they could become the youngest known pairs. In both cases, the relative encounter velocities of the components were only ˜ 0.1 m s^{-1}. However, the minimum distances between some clones are too large and a few clones of the latter pair did not encounter recently (within ≈ 10 kyr). The age of some prospective young pairs cannot be determined reliably without improved orbital properties (e.g., the second component of a pair

  5. 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.

  6. Multiple origins of asteroid pairs

    NASA Astrophysics Data System (ADS)

    Jacobson, Seth A.

    2016-01-01

    Rotationally fissioned asteroids produce unbound asteroid pairs that have very similar heliocentric orbits. Backward integration of their current heliocentric orbits provides an age of closest proximity that can be used to date the rotational fission event. Most asteroid pairs follow a predicted theoretical relationship between the primary spin period and the mass ratio of the two pair members that is a direct consequence of the YORP-induced rotational fission hypothesis. If the progenitor asteroid has strength, asteroid pairs may have higher mass ratios or faster rotating primaries. However, the process of secondary fission leaves the originally predicted trend unaltered. We also describe the characteristics of pair members produced by four alternative routes from a rotational fission event to an asteroid pair. Unlike direct formation from the event itself, the age of closest proximity of these pairs cannot generally be used to date the rotational fission event since considerable time may have passed.

  7. Lunar Exploration Insights Recognized from Chandrayaan-1 M3 Imaging Spectrometer

    NASA Astrophysics Data System (ADS)

    Pieters, Carle; Green, Robert O.; Boardman, Joseph

    2016-07-01

    One of the most important lessons learned from the renaissance of lunar exploration over the last decade is that new discoveries and surprises occur with every new mission to the Moon. Although the color of the Moon had been measured using Earth-based telescopes even before Apollo, modern instruments sent to orbit the Moon provide a scope of inquiry unimaginable during the last century. Spacecraft have now been successfully sent to the Moon by six different space agencies from around the world and the number is growing. The Indian Chandrayaan- 1 spacecraft carried a suite of indigenous instruments as well as several guest instruments from other countries, including the Moon Mineralogy Mapper (M-cube) supplied by NASA. Even though Chandrayaan's lifetime in orbit was shortened by technical constraints, M3 provided a taste of the power of near-infrared imaging spectroscopy used for science and exploration at the Moon. Contrary to expectations, the lunar surface was discovered to be hydrated, which is now known to result from solar wind H combining with O of rocks and soil. Surficial hydration was found to be pervasive across the Moon and the limited data hint at both local concentrations and temporal variations. The prime objective of M3 was to characterize lunar mineralogy in a spatial context. Working in tandem with related instruments on JAXA's SELENE, M3 readily recognized and mapped known minerals from mare and highland terrains (pyroxenes, olivine) at high resolution, but also detected diagnostic properties of crystalline plagioclase which, when mapped across a spatial context, enabled the unambiguous identification of a massive crustal layer of plagioclase that clearly resulted from an early magma ocean. An additional surprise came with the discovery of a new rock type on the Moon that had not been recognized in samples returned by Apollo and Luna: a Mg-rich spinel anorthosite associated with material excavated from some of the greatest lunar depths. In

  8. Lunar Magma Ocean Bedrock Anorthosites Detected at Orientale Basin by M3

    NASA Astrophysics Data System (ADS)

    Pieters, C. M.; Boardman, J. W.; Burratti, B.; Cheek, L.; Clark, R. N.; Combe, J.; Green, R. O.; Head, J. W.; Hicks, M.; Isaacson, P.; Klima, R.; Kramer, G. Y.; Lundeen, S.; Malaret, E.; McCord, T. B.; Mustard, J. F.; Nettles, J. W.; Petro, N. E.; Runyon, C. J.; Staid, M.; Sunshine, J. M.; Taylor, L. A.; Tompkins, S.; Varanasi, P.

    2009-12-01

    The lunar crust is thought to have formed as a result of global melting of the outer parts of the Moon in its earliest history, a lunar magma ocean (LMO). Crystallization of this magma ocean set the stage for the ensuing history of the planet. Models for the formation of the lunar crust and the evolution of the LMO were derived from individual Apollo samples that could not be placed directly in the context of crustal bedrock with remote sensing data that was available. Data from modern sensors, such as the Moon Mineralogy Mapper (M3) on Chandrayaan-1, now allow such bedrock issues to be addressed. The ~930 km diameter Orientale multi-ringed impact basin in the western highlands provides an opportunity to evaluate the mineralogy of the in situ crust of the Moon in the search for LMO mineralogy and structure. Orientale is the youngest large basin on the Moon, and the basin deposits and ring structures expose progressively deeper bedrock layering that can be used to determine lunar crustal structure and test the LMO model. With its high spatial and spectral resolution, M3 data show that the ejecta of the basin is composed of mixed assemblages of processed feldspathic breccias with small amounts of low-Ca pyroxene comprising the upper kilometers-thick mega-regolith layer of the crust. Exposures in the outermost (Cordillera) ring reveal less processed examples of this material. The M3 data show that the next interior ring (Outer Rook), representing deeper material, is characterized by distinctly more crystalline blocks of impact-shocked anorthosite and noritic anorthosite. Most importantly, M3 data reveal that the mountains of the closest ring toward the basin interior (Inner Rook) consist of pure anorthosite, including outcrops of the unshocked crystalline form. This massive exposure of anorthosite across the entire mountain range provides validation for the LMO hypothesis. These mountains are believed to have originated in the upper crust below the impact fragmented

  9. Cooper pairs spintronics in triplet spin valves.

    PubMed

    Romeo, F; Citro, R

    2013-11-27

    We study a spin valve with a triplet superconductor spacer intercalated between two ferromagnets with noncollinear magnetizations. We show that the magnetoresistance of the triplet spin valve depends on the relative orientations of the d vector, characterizing the superconducting order parameter, and the magnetization directions of the ferromagnetic layers. For devices characterized by a long superconductor, the effects of a polarized current sustained by Cooper pairs only are observed. In this regime, a supermagnetoresistance effect emerges, and the chiral symmetry of the order parameter of the superconducting spacer is easily recognized. Our findings open new perspectives in designing spintronics devices based on the cooperation of ferromagnetic and triplet correlations.

  10. Cooper pairs spintronics in triplet spin valves.

    PubMed

    Romeo, F; Citro, R

    2013-11-27

    We study a spin valve with a triplet superconductor spacer intercalated between two ferromagnets with noncollinear magnetizations. We show that the magnetoresistance of the triplet spin valve depends on the relative orientations of the d vector, characterizing the superconducting order parameter, and the magnetization directions of the ferromagnetic layers. For devices characterized by a long superconductor, the effects of a polarized current sustained by Cooper pairs only are observed. In this regime, a supermagnetoresistance effect emerges, and the chiral symmetry of the order parameter of the superconducting spacer is easily recognized. Our findings open new perspectives in designing spintronics devices based on the cooperation of ferromagnetic and triplet correlations. PMID:24329463

  11. Stereo Pair, Honolulu, Oahu

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Honolulu, on the island of Oahu, is a large and growing urban area. This stereoscopic image pair, combining a Landsat image with topography measured by the Shuttle Radar Topography Mission (SRTM), shows how topography controls the urban pattern. This color image can be viewed in 3-D by viewing the left image with the right eye and the right image with the left eye (cross-eyed viewing), or by downloading and printing the image pair, and viewing them with a stereoscope.

    Features of interest in this scene include Diamond Head (an extinct volcano near the bottom of the image), Waikiki Beach (just above Diamond Head), the Punchbowl National Cemetary (another extinct volcano, near the image center), downtown Honolulu and Honolulu harbor (image left-center), and offshore reef patterns. The slopes of the Koolau mountain range are seen in the right half of the image. Clouds commonly hang above ridges and peaks of the Hawaiian Islands, but in this synthesized stereo rendition appear draped directly on the mountains. The clouds are actually about 1000 meters (3300 feet) above sea level.

    This stereoscopic image pair was generated using topographic data from the Shuttle Radar Topography Mission, combined with a Landsat 7 Thematic Mapper image collected at the same time as the SRTM flight. The topography data were used to create two differing perspectives, one for each eye. When stereoscopically merged, the result is a vertically exaggerated view of the Earth's surface in its full three dimensions. The United States Geological Survey's Earth Resources Observations Systems (EROS) Data Center, Sioux Falls, South Dakota, provided the Landsat data.

    The Shuttle Radar Topography Mission (SRTM), launched on February 11, 2000, used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. The mission was designed to collect three-dimensional measurements of the

  12. Stereo Pair, Pasadena, California

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This stereoscopic image pair is a perspective view that shows the western part of the city of Pasadena, California, looking north toward the San Gabriel Mountains. Portions of the cities of Altadena and La Canada Flintridge are also shown. The cluster of large buildings left of center, at the base of the mountains, is the Jet Propulsion Laboratory. This image shows the power of combining data from different sources to create planning tools to study problems that affect large urban areas. In addition to the well-known earthquake hazards, Southern California is affected by a natural cycle of fire and mudflows. Data shown in this image can be used to predict both how wildfires spread over the terrain and how mudflows are channeled down the canyons.

    The image was created from three datasets: the Shuttle Radar Topography Mission (SRTM) supplied the elevation, U. S. Geological Survey digital aerial photography provided the image detail, and the Landsat Thematic Mapper provided the color. The United States Geological Survey's Earth Resources Observations Systems (EROS) Data Center, Sioux Falls, South Dakota, provided the Landsat data and the aerial photography. The image can be viewed in 3-D by viewing the left image with the right eye and the right image with the left eye (cross-eyed viewing), or by downloading and printing the image pair, and viewing them with a stereoscope.

    The Shuttle Radar Topography Mission (SRTM), launched on February 11, 2000, used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. The mission was designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200-foot) mast, an additional C-band imaging antenna and improved tracking and navigation devices. The mission is a cooperative project between the National Aeronautics and Space Administration

  13. Describing the heavy-ion above-barrier fusion using the bare potentials resulting from Migdal and M3Y double-folding approaches

    NASA Astrophysics Data System (ADS)

    Gontchar, I. I.; Chushnyakova, M. V.

    2016-08-01

    Systematic calculations of the Coulomb barrier parameters for collisions of spherical nuclei are performed within the framework of the double folding approach. The value of the parameter {B}Z={Z}P{Z}T/({A}P{1/3}+{A}T{1/3}) (which estimates the Coulomb barrier height) varies in these calculations from 10 MeV up to 150 MeV. The nuclear densities came from the Hartree-Fock calculations which reproduce the experimental charge densities with good accuracy. For the nucleon-nucleon effective interaction two analytical approximations known in the literature are used: the M3Y and Migdal forces. The calculations show that Migdal interaction always results in the higher Coulomb barrier. Moreover, as B Z increases the difference between the M3Y and Migdal barrier heights systematically increases as well. As the result, the above barrier fusion cross sections calculated dynamically with the M3Y forces and surface friction are in agreement with the data. The cross sections calculated with the Migdal forces are always below the experimental data even without accounting for the dissipation.

  14. Functional renormalization-group study of the pairing symmetry and pairing mechanism of the FeAs-based high-temperature superconductor.

    PubMed

    Wang, Fa; Zhai, Hui; Ran, Ying; Vishwanath, Ashvin; Lee, Dung-Hai

    2009-01-30

    We apply the fermion functional renormalization-group method to determine the pairing symmetry and pairing mechanism of the FeAs-Based materials. Within a five band model with pure repulsive interactions, we find an electronic-driven superconducting pairing instability. For the doping and interaction parameters we have examined, extended s wave, whose order parameter takes on opposite sign on the electron and hole pockets, is always the most favorable pairing symmetry. The pairing mechanism is the inter-Fermi-surface Josephson scattering generated by the antiferromagnetic correlation.

  15. Pygmy stars: first pair.

    PubMed

    Zwicky, F

    1966-07-01

    The binary LP 101-15/16 having the proper motion of 1.62 seconds of arc per year has been studied with the prime-focus spectrograph of the 200-inch (508 cm) telescope. Indications are that LP 101-15/16 is the first pair of pygmy stars ever discovered. One of its components, LP 101-16, is probably a blue pygmy star which is at least four magnitudes fainter than the ordinary white dwarfs. Also, two of the Balmer lines in absorption appear to be displaced toward the red by amounts which indicate the existence of an Einstein gravitational red shift corresponding to about 1000 km sec-1. On the other hand LP 101-15 is red and shows an entirely new type of spectrum, which suggests that it may be a first representative of a type of red pygmy star which is 2.5 magnitudes fainter than the M-type dwarf stars of the main sequence. PMID:17730606

  16. Pygmy stars: first pair.

    PubMed

    Zwicky, F

    1966-07-01

    The binary LP 101-15/16 having the proper motion of 1.62 seconds of arc per year has been studied with the prime-focus spectrograph of the 200-inch (508 cm) telescope. Indications are that LP 101-15/16 is the first pair of pygmy stars ever discovered. One of its components, LP 101-16, is probably a blue pygmy star which is at least four magnitudes fainter than the ordinary white dwarfs. Also, two of the Balmer lines in absorption appear to be displaced toward the red by amounts which indicate the existence of an Einstein gravitational red shift corresponding to about 1000 km sec-1. On the other hand LP 101-15 is red and shows an entirely new type of spectrum, which suggests that it may be a first representative of a type of red pygmy star which is 2.5 magnitudes fainter than the M-type dwarf stars of the main sequence.

  17. Dynamical evolution of comet pairs

    NASA Astrophysics Data System (ADS)

    Sosa, Andrea; Fernández, Julio A.

    2016-10-01

    Some Jupiter family comets in near-Earth orbits (thereafter NEJFCs) show a remarkable similarity in their present orbits, like for instance 169P/NEAT and P/2003 T12 (SOHO), or 252P/LINEAR and P/2016 BA14 (PANSTARRS). By means of numerical integrations we studied the dynamical evolution of these objects. In particular, for each pair of presumably related objects, we are interested in assessing the stability of the orbital parameters for several thousand years, and to find a minimum of their relative spatial distance, coincident with a low value of their relative velocity. For those cases for which we find a well defined minimum of their relative orbital separation, we are trying to reproduce the actual orbit of the hypothetical fragment by modeling a fragmentation of the parent body. Some model parameters are the relative ejection velocity (a few m/s), the orbital point at which the fragmentation could have happened (e.g. perihelion), and the elapsed time since fragmentation. In addition, some possible fragmentation mechanisms, like thermal stress, rotational instability, or collisions, could be explored. According to Fernández J.A and Sosa A. 2015 (Planetary and Space Science 118,pp.14-24), some NEJFCs might come from the outer asteroid belt, and then they would have a more consolidated structure and a higher mineral content than that of comets coming from the trans-Neptunian belt or the Oort cloud. Therefore, such objects would have a much longer physical lifetime in the near-Earth region, and could become potential candidates to produce visible meteor showers (as for example 169P/NEAT which has been identified as the parent body of the alpha-Capricornid meteoroid stream, according to Jenniskens, P., Vaubaillon, J., 2010 (Astron. J. 139), and Kasuga, T., Balam, D.D., Wiegert, P.A., 2010 (Astron. J. 139).

  18. Verrucotoxin inhibits KATP channels in cardiac myocytes through a muscarinic M3 receptor-PKC pathway.

    PubMed

    Wang, Jian-Wu; Yazawa, Kazuto; Hao, Li-Ying; Onoue, Yoshio; Kameyama, Masaki

    2007-06-01

    Verrucotoxin is the major component of venom from the stonefish (Synanceia verrucosa). Stings from the dorsal spines of the stonefish produce intensive pain, convulsions, hypotension, paralysis, respiratory weakness and collapse of the cardiovascular system, occasionally leading to death. It has been reported that verrucotoxin might modulate ATP-sensitive K+ (KATP) current in frog atrial fibers. However, the mechanism by which verrucotoxin acts on KATP current remains unclear. In this study, we examined whether verrucotoxin inhibited KATP current in guinea pig ventricular myocytes, using the patch clamp method. Verrucotoxin suppressed KATP current induced by pinacidil (KATP channel opener) in a concentration-dependent manner, with a half maximum concentration of 16.3 microg/ml. The effect of verrucotoxin on KATP current was suppressed by atropine (1 microM), a muscarinic receptor antagonist, or by 4-diphenylacetoxy-N-methylpiperidine (100 nM), a muscarinic M3 receptor antagonist. Furthermore, the effect of verrucotoxin on KATP current was attenuated by the protein kinase C (PKC) inhibitor chelerythrine (10 microM) and calphostin C (10 microM), yet not by the cAMP-dependent protein kinase (PKA) inhibitor H-89 (0.5 microM). These results suggest that verrucotoxin inhibits KATP current through the muscarinic M3 receptor-PKC pathway. These findings enhance our understanding of the toxic effects of verrucotoxin from the stonefish. PMID:17362922

  19. ON THE MODULATION OF RR LYRAE STARS IN THE GLOBULAR CLUSTER M3

    SciTech Connect

    Jurcsik, J.; Smitola, P.; Nuspl, J.; Hajdu, G.

    2014-12-10

    New, extended time-series photometry of M3 RR Lyrae stars has revealed that 4 of the 10 double-mode stars show large-amplitude Blazhko modulation of both radial modes. The first, detailed analysis of the peculiar behavior of the unique, Blazhko RRd stars is given. While the P1/P0 period ratio is normal, and the overtone mode is dominant in the other RRd stars of the cluster, the period ratio is anomalous and the fundamental mode has a larger (or similar) mean amplitude than the overtone has in Blazhko RRd stars. The modulations of the fundamental and overtone modes are synchronized only in one of the Blazhko RRd stars. No evidence of any connection between the modulations of the modes in the other three stars is found. The Blazhko modulation accounts, at least partly, for the previously reported amplitude and period changes of these stars. Contrary to the ∼50% Blazhko statistics of RRab and RRd stars, Blazhko modulation occurs only in 10% of the overtone variables in M3. Four of the five Blazhko RRc stars are bright, evolved objects, and one has a period and brightness similar to those of Blazhko RRd stars. The regions of the instability strip with high and low occurrence rates of the Blazhko modulation overlap with the regions populated by first- and second-generation stars according to theoretical and observational studies, raising up the possibility that the Blazhko modulation occurs preferentially in first-generation RR Lyrae stars.

  20. Expression of the rat muscarinic receptor gene m3 in Dictyostelium discoideum.

    PubMed

    Voith, G; Kramm, H; Zündorf, I; Winkler, T; Dingermann, T

    1998-10-01

    We functionally expressed the rat muscarinic m3 receptor (rm3) in the cellular slime mold Dictyostelium discoideum under the control of the homologous discoidin I gamma promoter. Cells transfected with the authentic rm3 receptor gene expressed about 100 functional receptor molecules per cell, corresponding to a Bmax for [3H]-NMS of 36 +/- 9 fmol/mg of protein in isolated membranes. Genetic fusion of the Dictyostelium contact site A (csA) leader peptide to the amino terminus of rm3 increased the receptor expression by about 17-fold. Remarkable, in [3H]-NMS ligand binding experiments performed with whole cells no characteristic saturable binding was observed and there was no significant difference in [3H]-NMS binding to whole cells of rm3 and csA/rm3 transformants. The recombinant rm3 receptor showed an about 10-fold higher affinity to the M3-selective antagonist p-F-HHSiD compared to the M2-selective antagonist AQ-RA 741, suggesting that membranes derived from transgenic D. discoideum cells may be useful for the search of new subtype-specific muscarinic receptor ligands. PMID:9812338

  1. NOTE: Adapting a generic BEAMnrc model of the BrainLAB m3 micro-multileaf collimator to simulate a local collimation device

    NASA Astrophysics Data System (ADS)

    Kairn, T.; Aland, T.; Franich, R. D.; Johnston, P. N.; Kakakhel, M. B.; Kenny, J.; Knight, R. T.; Langton, C. M.; Schlect, D.; Taylor, M. L.; Trapp, J. V.

    2010-09-01

    This work is focussed on developing a commissioning procedure so that a Monte Carlo model, which uses BEAMnrc's standard VARMLC component module, can be adapted to match a specific BrainLAB m3 micro-multileaf collimator (µMLC). A set of measurements are recommended, for use as a reference against which the model can be tested and optimized. These include radiochromic film measurements of dose from small and offset fields, as well as measurements of µMLC transmission and interleaf leakage. Simulations and measurements to obtain µMLC scatter factors are shown to be insensitive to relevant model parameters and are therefore not recommended, unless the output of the linear accelerator model is in doubt. Ultimately, this note provides detailed instructions for those intending to optimize a VARMLC model to match the dose delivered by their local BrainLAB m3 µMLC device.

  2. Pairs of promoter pairs in a web of transcription.

    PubMed

    Kaplan, Craig D

    2016-08-30

    A new analysis has characterized a fundamental building block of complex transcribed loci. Constellations of core promoters can generally be reduced to pairs of divergent transcription units, where the distance between the pairs of transcription units correlates with constraints on genomic context, which in turn contribute to transcript fate. PMID:27573684

  3. Pairs of promoter pairs in a web of transcription.

    PubMed

    Kaplan, Craig D

    2016-08-30

    A new analysis has characterized a fundamental building block of complex transcribed loci. Constellations of core promoters can generally be reduced to pairs of divergent transcription units, where the distance between the pairs of transcription units correlates with constraints on genomic context, which in turn contribute to transcript fate.

  4. M3D-K simulations of sawteeth and energetic particle transport in tokamak plasmas

    SciTech Connect

    Shen, Wei; Sheng, Zheng-Mao; Fu, G. Y.; Breslau, J. A.; Wang, Feng

    2014-09-15

    Nonlinear simulations of sawteeth and related energetic particle transport are carried out using the kinetic/magnetohydrodynamic (MHD) hybrid code M3D-K. MHD simulations show repeated sawtooth cycles for a model tokamak equilibrium. Furthermore, test particle simulations are carried out to study the energetic particle transport due to a sawtooth crash. The results show that energetic particles are redistributed radially in the plasma core, depending on pitch angle and energy. For trapped particles, the redistribution occurs for particle energy below a critical value in agreement with existing theories. For co-passing particles, the redistribution is strong with little dependence on particle energy. In contrast, the redistribution level of counter-passing particles decreases with increasing particle energy.

  5. Constraints on Helium Enhancement in the Globular Cluster M3 (NGC 5272): The Horizontal Branch Test

    NASA Technical Reports Server (NTRS)

    Catelan, M.; Grundahl, F.; Sweigart, A. V.; Valcarce, A. A. R.; Cortes, C.

    2007-01-01

    It has recently been suggested that the presence of multiple populations showing various amounts of helium enhancement is a common feature among globular star clusters. In this scenario, such a helium enhancement would be particularly apparent in the enhanced luminosity of thc blue horizontal branch (HB) stars compared to the red HB stars. In this Letter, wc test this scenario in the case of the Galactic globular cluster M3 (NGC 5272), using high-precision Stromgren photometry and spectroscopic gravities for blue HB stars. We find that any helium enhancement among the cluster's blue HB stars must be significantly less than I%, thus ruling out the much higher helium enhancements that have been proposed in the literature.

  6. Magnetic, Thermal and Dynamical Evolution of AN M3.2 Two-Ribbon Flare

    NASA Astrophysics Data System (ADS)

    Collados, Manuel; Kuckein, Christoph; Manso Sainz, Rafael; Asensio Ramos, Andres

    On 2013, 17th May, a two-ribbon M3.2 flare took place in the solar atmosphere on the active region AR 11748. The flare evolution was observed at the German VTT of the Observatorio del Teide using the instrument TIP-II, with spectropolarimetric measurements of the photosphere (Si I at 1082.7 nm) and the chromosphere (Helium triplet at 1083 nm). Simultaneous spectroscopic data of the chromospheric spectral line of Ca II at 854.2 nm and filtergrams at Halpha were also obtained. The flare evolution as observed from the ground can be compared with the changes observed by AIA@SDO at different ultraviolet wavelengths. The ground observations covered several hours, including the pre-flare, impulsive, gradual and post-flare phases. We present maps of the magnetic field, thermal and dynamical properties of the region during its evolution from pre- to post-flare phase.

  7. The phase 0/A study of the ESA M3 mission candidate EChO

    NASA Astrophysics Data System (ADS)

    Puig, Ludovic; Isaak, Kate; Linder, Martin; Escudero, Isabel; Crouzet, Pierre-Elie; Walker, Roger; Ehle, Matthias; Hübner, Jutta; Timm, Rainer; de Vogeleer, Bram; Drossart, Pierre; Hartogh, Paul; Lovis, Christophe; Micela, Giusi; Ollivier, Marc; Ribas, Ignasi; Snellen, Ignas; Swinyard, Bruce; Tinetti, Giovanna; Eccleston, Paul

    2015-12-01

    EChO, the Exoplanet Characterisation Observatory, has been one of the five M-class mission candidates competing for the M3 launch slot within the science programme Cosmic Vision 2015-2025 of the European Space Agency (ESA). As such, EChO has been the subject of a Phase 0/A study that involved European Industry, research institutes and universities from ESA member states and that concluded in September 2013. EChO is a concept for a dedicated mission to measure the chemical composition and structure of hundreds of exoplanet atmospheres using the technique of transit spectroscopy. With simultaneous and uninterrupted spectral coverage from the visible to infrared wavelengths, EChO targets extend from gas giants (Jupiter or Neptune-like) to super-Earths in the very hot to temperate zones of F to M-type host stars, opening up the way to large-scale, comparative planetology that would place our own solar system in the context of other planetary systems in the Milky Way. A review of the performance requirements of the EChO mission was held at ESA at the end of 2013, with the objective of assessing the readiness of the mission to progress to the Phase B1 study phase. No critical issues were identified from a technical perspective, however a number of recommendations were made for future work. Since the mission was not selected for the M3 launch slot, EChO is no longer under study at ESA. In this paper we give an overview of the final mission concept for EChO as of the end of the study, from scientific, technical and operational perspectives.

  8. An Extremely Lithium-rich Bright Red Giant in the Globular Cluster M3

    NASA Astrophysics Data System (ADS)

    Kraft, Robert P.; Peterson, Ruth C.; Guhathakurta, Puragra; Sneden, Christopher; Fulbright, Jon P.; Langer, G. Edward

    1999-06-01

    We have serendipitously discovered an extremely lithium-rich star on the red giant branch of the globular cluster M3 (NGC 5272). An echelle spectrum obtained with the Keck I High-Resolution Echelle Spectrograph reveals a Li I λ6707 resonance doublet of 520 mÅ equivalent width, and our analysis places the star among the most Li-rich giants known: logε(Li)~=+3.0. We determine the elemental abundances of this star, IV-101, and three other cluster members of similar luminosity and color and conclude that IV-101 has abundance ratios typical of giants in M3 and M13 that have undergone significant mixing. We discuss mechanisms by which a low-mass star may be so enriched in Li, focusing on the mixing of material processed by the hydrogen-burning shell just below the convective envelope. While such enrichment could conceivably happen only rarely, it may in fact regularly occur during giant-branch evolution but be rarely detected because of rapid subsequent Li depletion. Based on observations obtained with the Keck I Telescope of the W. M. Keck Observatory, which is operated by the California Association for Research in Astronomy (CARA), Inc., on behalf of the University of California and the California Institute of Technology. This Letter is dedicated to the memory of our beloved colleague Ed Langer, who died after a brief illness on February 16, 1999. Ed brought a unique theoretical perspective to our globular cluster abundance studies. His career truly embodied the academic ideals of inspiration in both teaching and research. He made friends wherever he traveled, and was an inspiration to students. We will miss him greatly.

  9. 12 CFR Appendix M3 to Part 226 - Sample Calculations of Generic Repayment Estimates and Actual Repayment Disclosures

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 3 2010-01-01 2010-01-01 false Sample Calculations of Generic Repayment Estimates and Actual Repayment Disclosures M3 Appendix M3 to Part 226 Banks and Banking FEDERAL RESERVE SYSTEM (CONTINUED) BOARD OF GOVERNORS OF THE FEDERAL RESERVE SYSTEM TRUTH IN LENDING (REGULATION Z)...

  10. Three-component fermion pairing in two dimensions

    SciTech Connect

    De Silva, Theja N.

    2009-07-15

    We study pairing of an interacting three-component Fermi gas in two dimensions. By using a mean-field theory to decouple the interactions between different pairs of Fermi components, we study the free energy landscapes as a function of various system parameters including chemical potentials, binding energies, and temperature. We find that the s-wave pairing channel is determined by both chemical potentials and the interaction strengths between the three available channels. We find a second-order thermal phase transition and a series of first-order quantum phase transitions for a homogenous system as we change the parameters. In particular, for symmetric parameters, we find the simultaneous existence of three superfluid orders as well as re-entrant quantum phase transitions as we tune the parameters.

  11. Assessment Strategies for Pair Programming

    ERIC Educational Resources Information Center

    Hahn, Jan Hendrik; Mentz, Elsa; Meyer, Lukas

    2009-01-01

    Although pair programming has proved its usefulness in teaching and learning programming skills, it is difficult to assess the individual roles and abilities of students whilst programming in pairs. (Note that within this manuscript, the term assessment refers to evaluating individual student performance.) Assessing only the outcomes of a pair…

  12. Soluble M3 proteins of murine gammaherpesviruses 68 and 72 expressed in Escherichia coli: analysis of chemokine-binding properties.

    PubMed

    Matúšková, R; Pančík, P; Štibrániová, I; Belvončíková, P; Režuchová, I; Kúdelová, M

    2015-12-01

    M3 protein of murine gammaherpesvirus 68 (MHV-68) was identified as a viral chemokine-binding protein 3 (vCKBP-3) capable to bind a broad spectrum of chemokines and their receptors. During both acute and latent infection MHV-68 M3 protein provides a selective advantage for the virus by inhibiting the antiviral and inflammatory response. A unique mutation Asp307Gly was identified in the M3 protein of murine gammaherpesvirus 72 (MHV-72), localized near chemokine-binding domain. Study on chemokine-binding properties of MHV-72 M3 protein purified from medium of infected cells implied reduced binding to some chemokines when compared to MHV-68 M3 protein. It was suggested that the mutation in the M3 protein might be involved in the attenuation of immune response to infection with MHV-72. Recently, Escherichia coli cells were used to prepare native recombinant M3 proteins of murine gammaherpesviruses 68 and 72 (Pančík et al., 2013). In this study, we assessed the chemokine-binding properties of three M3 proteins prepared in E. coli Rosetta-gami 2 (DE3) cells, the full length M3 protein of both MHV-68 and MHV-72 and MHV-68 M3 protein truncated in the signal sequence (the first 24 aa). They all displayed binding activity to human chemokines CCL5 (RANTES), CXCL8 (IL-8), and CCL3 (MIP-1α). The truncated MHV-68 M3 protein had more than twenty times reduced binding activity to CCL5, but only about five and three times reduced binding to CXCL8 and CCL3 when compared to its full length counterpart. Binding of the full length MHV-72 M3 protein to all chemokines was reduced when compared to MHV-68 M3 protein. Its binding to CCL5 and CCL3 was reduced over ten and seven times. However, its binding to CXCL8 was only slightly reduced (64.8 vs 91.8%). These data implied the significance of the signal sequence and also of a single mutation (at aa 307) for efficient M3 protein binding to some chemokines.

  13. Insight into the pseudo π-hole interactions in the M3H6(NCF)n (M = C, Si, Ge, Sn, Pb; n = 1, 2, 3) complexes.

    PubMed

    Li, Wei; Zeng, Yanli; Li, Xiaoyan; Sun, Zheng; Meng, Lingpeng

    2016-09-21

    For cyclopropane and its derivatives M3H6 (M = C, Si, Ge, Sn, Pb), "pseudo π-hole" regions above and below the M-M-M three-membered ring have been discovered, and pseudo π-hole interactions between M3H6 and F-CN have been designed and investigated by MP2/aug-cc-pVTZ and MP2/aug-cc-pVTZ-pp calculations. To investigate the enhancing effects of FN halogen bonds on the pseudo π-hole interactions, the termolecular and tetramolecular complexes M3H6(NCF)n (n = 2, 3) were constructed. Energy decomposition analysis shows that the dispersion term contributes the most among the three attractive components in the C3H6(NCF)n (n = 1, 2, 3) complexes while in the Si3H6(NCF)n and Ge3H6(NCF)n complexes, the electrostatic term has the largest contribution. The electrostatic and polarization energies have more effect than the dispersion energy for the enhancement of the FN halogen bond on the pseudo π-hole interactions. With the increase in the number of NCF units from 1 to 3, the VS,min values outside the nitrogen atom of NCF become increasingly negative, the electric field of the lone pair of nitrogen becomes greater and causes a further increase of electron density outside the nitrogen atom and a further decrease of electron density outside the pseudo π-hole region, resulting in a stronger pseudo π-hole interaction.

  14. Insight into the pseudo π-hole interactions in the M3H6(NCF)n (M = C, Si, Ge, Sn, Pb; n = 1, 2, 3) complexes.

    PubMed

    Li, Wei; Zeng, Yanli; Li, Xiaoyan; Sun, Zheng; Meng, Lingpeng

    2016-09-21

    For cyclopropane and its derivatives M3H6 (M = C, Si, Ge, Sn, Pb), "pseudo π-hole" regions above and below the M-M-M three-membered ring have been discovered, and pseudo π-hole interactions between M3H6 and F-CN have been designed and investigated by MP2/aug-cc-pVTZ and MP2/aug-cc-pVTZ-pp calculations. To investigate the enhancing effects of FN halogen bonds on the pseudo π-hole interactions, the termolecular and tetramolecular complexes M3H6(NCF)n (n = 2, 3) were constructed. Energy decomposition analysis shows that the dispersion term contributes the most among the three attractive components in the C3H6(NCF)n (n = 1, 2, 3) complexes while in the Si3H6(NCF)n and Ge3H6(NCF)n complexes, the electrostatic term has the largest contribution. The electrostatic and polarization energies have more effect than the dispersion energy for the enhancement of the FN halogen bond on the pseudo π-hole interactions. With the increase in the number of NCF units from 1 to 3, the VS,min values outside the nitrogen atom of NCF become increasingly negative, the electric field of the lone pair of nitrogen becomes greater and causes a further increase of electron density outside the nitrogen atom and a further decrease of electron density outside the pseudo π-hole region, resulting in a stronger pseudo π-hole interaction. PMID:27545836

  15. Guanidinium Pairing Facilitates Membrane Translocation.

    PubMed

    Allolio, Christoph; Baxova, Katarina; Vazdar, Mario; Jungwirth, Pavel

    2016-01-14

    Ab initio free energy calculations of guanidinium pairing in aqueous solution confirm the counterintuitive conjecture that the like-charge ion pair is thermodynamically stable. Transferring the guanidinium pair to the inside of a POPC lipid bilayer, like-charge ion pairing is found to occur also inside the membrane defect. It is found to contribute to the nonadditivity of ion transfer, thereby facilitating the presence of ions inside the bilayer. The effect is quantified by free energy decomposition and comparison with ammonium ions, which do not form a stable pair. The presence of two charges inside the center of the bilayer leads to the formation of a pore. Potential consequences for cell penetrating peptides and ion conduction are drawn.

  16. Locomotion gaits of a rotating cylinder pair

    NASA Astrophysics Data System (ADS)

    van Rees, Wim M.; Novati, Guido; Koumoutsakos, Petros; Mahadevan, L.

    2015-11-01

    Using 2D numerical simulations of the Navier-Stokes equations, we demonstrate that a simple pair of rotating cylinders can display a range of locomotion patterns of biological and engineering interest. Steadily counter-rotating the cylinders causes the pair to move akin to a vortex dipole for low rotation rates, but as the rotational velocity is increased the direction of motion reverses. Unsteady rotations lead to different locomotion gaits that resemble jellyfish (for in-phase rotations) and undulating swimmers (for out-of-phase rotations). The small number of parameters for this simple system allows us to systematically map the phase space of these gaits, and allows us to understand the underlying physical mechanisms using a minimal model with implications for biological locomotion and engineered analogs.

  17. Resonant tunneling of fluctuation Cooper pairs

    DOE PAGES

    Galda, Alexey; Mel'nikov, A. S.; Vinokur, V. M.

    2015-02-09

    Superconducting fluctuations have proved to be an irreplaceable source of information about microscopic and macroscopic material parameters that could be inferred from the experiment. According to common wisdom, the effect of thermodynamic fluctuations in the vicinity of the superconducting transition temperature, Tc, is to round off all of the sharp corners and discontinuities, which otherwise would have been expected to occur at Tc. Here we report the current spikes due to radiation-induced resonant tunneling of fluctuation Cooper pairs between two superconductors which grow even sharper and more pronounced upon approach to Tc. This striking effect offers an unprecedented tool formore » direct measurements of fluctuation Cooper pair lifetime, which is key to our understanding of the fluctuation regime, most notably to nature of the pseudogap state in high-temperature superconductors. Our finding marks a radical departure from the conventional view of superconducting fluctuations as a blurring and rounding phenomenon.« less

  18. Pseudogap Pairing in Ultracold Fermi Atoms

    SciTech Connect

    Hu Hui; Liu Xiaji; Drummond, Peter D.; Dong Hui

    2010-06-18

    The Bose-Einstein condensate to Bardeen-Cooper-Schrieffer crossover in ultracold Fermi gases creates an ideal environment to enrich our knowledge of many-body systems. It is relevant to a wide range of fields from condensed matter to astrophysics. The nature of pairing in strongly interacting Fermi gases can be readily studied. This aids our understanding of related problems in high-T{sub c} superconductors, whose mechanism is still under debate due to the large interaction parameter. Here, we calculate the dynamical properties of a normal, trapped strongly correlated Fermi gas, by developing a quantum cluster expansion. Our calculations for the single-particle spectral function agree with recent rf spectroscopy measurements, and clearly demonstrate pseudogap pairing in the strongly interacting regime.

  19. Resonant tunneling of fluctuation Cooper pairs

    SciTech Connect

    Galda, Alexey; Mel'nikov, A. S.; Vinokur, V. M.

    2015-02-09

    Superconducting fluctuations have proved to be an irreplaceable source of information about microscopic and macroscopic material parameters that could be inferred from the experiment. According to common wisdom, the effect of thermodynamic fluctuations in the vicinity of the superconducting transition temperature, Tc, is to round off all of the sharp corners and discontinuities, which otherwise would have been expected to occur at Tc. Here we report the current spikes due to radiation-induced resonant tunneling of fluctuation Cooper pairs between two superconductors which grow even sharper and more pronounced upon approach to Tc. This striking effect offers an unprecedented tool for direct measurements of fluctuation Cooper pair lifetime, which is key to our understanding of the fluctuation regime, most notably to nature of the pseudogap state in high-temperature superconductors. Our finding marks a radical departure from the conventional view of superconducting fluctuations as a blurring and rounding phenomenon.

  20. Base pairing and base mis-pairing in nucleic acids

    NASA Technical Reports Server (NTRS)

    Wang, A. H. J.; Rich, A.

    1986-01-01

    In recent years we have learned that DNA is conformationally active. It can exist in a number of different stable conformations including both right-handed and left-handed forms. Using single crystal X-ray diffraction analysis we are able to discover not only additional conformations of the nucleic acids but also different types of hydrogen bonded base-base interactions. Although Watson-Crick base pairings are the predominant type of interaction in double helical DNA, they are not the only types. Recently, we have been able to examine mismatching of guanine-thymine base pairs in left-handed Z-DNA at atomic resolution (1A). A minimum amount of distortion of the sugar phosphate backbone is found in the G x T pairing in which the bases are held together by two hydrogen bonds in the wobble pairing interaction. Because of the high resolution of the analysis we can visualize water molecules which fill in to accommodate the other hydrogen bonding positions in the bases which are not used in the base-base interactions. Studies on other DNA oligomers have revealed that other types of non-Watson-Crick hydrogen bonding interactions can occur. In the structure of a DNA octamer with the sequence d(GCGTACGC) complexed to an antibiotic triostin A, it was found that the two central AT base pairs are held together by Hoogsteen rather than Watson-Crick base pairs. Similarly, the G x C base pairs at the ends are also Hoogsteen rather than Watson-Crick pairing. Hoogsteen base pairs make a modified helix which is distinct from the Watson-Crick double helix.

  1. Stereo Pair: Patagonia, Argentina

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This view of northern Patagonia, near El Cain, Argentina shows complexly eroded volcanic terrain, with basalt mesas, sinkholes, landslide debris, playas, and relatively few integrated drainage channels. Surrounding this site (but also extending far to the east) is a broad plateau capped by basalt, the Meseta de Somuncura. Here, near the western edge of the plateau, erosion has broken through the basalt cap in a variety of ways. On the mesas, water-filled sinkholes (lower left) are most likely the result of the collapse of old lava tubes. Along the edges of the mesas (several locations) the basalt seems to be sliding away from the plateau in a series of slices. Water erosion by overland flow is also evident, particularly in canyons where vegetation blankets the drainage channels (green patterns, bottom of image). However, overland water flow does not extend very far at any location. This entire site drains to local playas, some of which are seen here (blue). While the water can reach the playas and then evaporate, what becomes of the eroded rock debris? Wind might excavate some of the finer eroded debris, but the fate of much of the missing bedrock remains mysterious.

    This cross-eyed stereoscopic image pair was generated using topographic data from the Shuttle Radar Topography Mission, combined with an enhanced Landsat 7 satellite color image. The topography data are used to create two differing perspectives of a single image, one perspective for each eye. In doing so, each point in the image is shifted slightly, depending on its elevation. When stereoscopically merged, the result is a vertically exaggerated view of the Earth's surface in its full three dimensions.

    Landsat satellites have provided visible light and infrared images of the Earth continuously since 1972. SRTM topographic data match the 30-meter (99-foot) spatial resolution of most Landsat images and provide a valuable complement for studying the historic and growing Landsat data archive. The

  2. Stereo Pair, Patagonia, Argentina

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This view of northern Patagonia, at Los Menucos, Argentina shows remnants of relatively young volcanoes built upon an eroded plain of much older and contorted volcanic, granitic, and sedimentary rocks. The large purple, brown, and green 'butterfly' pattern is a single volcano that has been deeply eroded. Large holes on the volcano's flanks indicate that they may have collapsed soon after eruption, as fluid molten rock drained out from under its cooled and solidified outer shell. At the upper left, a more recent eruption occurred and produced a small volcanic cone and a long stream of lava, which flowed down a gully. At the top of the image, volcanic intrusions permeated the older rocks resulting in a chain of small dark volcanic peaks. At the top center of the image, two halves of a tan ellipse pattern are offset from each other. This feature is an old igneous intrusion that has been split by a right-lateral fault. The apparent offset is about 6.6 kilometers (4 miles). Color, tonal, and topographic discontinuities reveal the fault trace as it extends across the image to the lower left. However, young unbroken basalt flows show that the fault has not been active recently.

    This cross-eyed stereoscopic image pair was generated using topographic data from the Shuttle Radar Topography Mission, combined with an enhanced Landsat 7satellite color image. The topography data are used to create two differing perspectives of a single image, one perspective for each eye. In doing so, each point in the image is shifted slightly, depending on its elevation. When stereoscopically merged, the result is a vertically exaggerated view of the Earth's surface in its full three dimensions.

    Landsat satellites have provided visible light and infrared images of the Earth continuously since 1972. SRTM topographic data match the 30-meter (99-foot) spatial resolution of most Landsat images and provide a valuable complement for studying the historic and growing Landsat data archive

  3. Spectral Signature of Lunar Pyroclastic Deposits in Moon Mineralogy (M3) data

    NASA Astrophysics Data System (ADS)

    Besse, Sebastien; Jawin, Erica; Mazrouei, Sara; Gaddis, Lisa; Sunshine, Jessica

    2013-04-01

    Over 100 pyroclastic deposits, or Dark Mantle Deposits (DMDs) have been identified on the Moon, with areas ranging from 10 km2 to over 50,000 km2. These regions of low-albedo, fine-grained material can vary significantly in composition. Larger DMDs such as those at Taurus-Littrow and Mare Vaporum are known to contain iron- and titanium-rich glass and devitrified beads, while smaller DMDs are typically comprised of iron-bearing mafic minerals such as pyroxene and olivine in juvenile and non-juvenile volcanic components. More recently at the large DMD in Sinus Aestuum, chromite spinel has been discovered. In this project we use spectroscopic data from the Moon Mineralogy Mapper (M3) to characterize the composition of various pyroclastic deposits across the lunar nearside. Using these data, we characterized the 1- and 2 μm mafic absorption bands for each pyroclastic region of interest, and analyzed the variation in composition between all regions. DMD compositional variations will help us to understand both the origin and mode of emplacement of these deposits. The four regions of interest chosen for this study include pyroclastic deposits in J. Herschel crater (36.6°W, 61.7°N), Alphonsus crater (3°W, 13.6°S), near the Apollo 17 landing site in the Taurus-Littrow valley (30.7°E, 20.2°N), and western Mare Vaporum (7.9°E, 10°N). There is complete or near-complete coverage of M3 data in these regions, including coverage in orbital periods OP1A, OP1B, OP2A, OP2C1, and OP2C3. Additionally, there is coverage over all four regions of interest in OP1B. This configuration allows studies of the DMDs with the same resolution and detector temperature, factors which can drastically change the spectral behavior of the M3 data. Several color composite images were created to highlight surface composition and to characterize the four pyroclastic deposits. The pyroclastic deposits within a given region of interest share similar spectral characteristics, even at sites where the

  4. High-pressure/high-temperature synthesis and characterization of the first palladium or platinum containing lithium transition-metal sulfides Li2M3S4 (M=Pd, Pt)

    NASA Astrophysics Data System (ADS)

    Heymann, Gunter; Niehaus, Oliver; Krüger, Hannes; Selter, Philipp; Brunklaus, Gunther; Pöttgen, Rainer

    2016-10-01

    The new lithium transition-metal sulfides Li2M3S4 (M=Pd, Pt) were obtained via multianvil high-pressure/high-temperature syntheses at 8 GPa and 1150 °C starting from a stoichiometric mixture of lithium nitride, sulfur, and palladium or platinum. Single crystal structure analyses indicated the space group P21/c (no. 14) with the following lattice parameters and refinement results: a=492.9(1), b=1005.9(2), c=614.9(2) pm, β=110.9 (1)°, R1=0.0165, wR2=0.0308 (all data) for Li2Pd3S4 and a=498.2(1), b=1005.5(2), c=613.0(2) pm, β=110.8(1)°, R1=0.0215, wR2=0.0450 (all data) for Li2Pt3S4. The crystal structures are built up from two distinct Pd/Pt sites, one of which is a special position (0,0,0), two sulfur sites, and one lithium site. The atoms Pd2/Pt2 form isolated square planar PdS4/PtS4 units, whereas the Pd1/Pt1 atoms form pairs of square planar PdS4/PtS4 units, which are connected via a common edge. These two structural motives built up a three-dimensional network structure by linking through common corners. The lithium atoms are positioned inside of the so formed channels. Li2M3S4 (M=Pd, Pt) are isostructural to the minerals jaguéite, Cu2Pd3Se4 and chrisstanleyite, Ag2Pd3Se4, which are up to now the only representatives of this structure type. Both compounds were studied with respect to their magnetic properties and can be classified as Pauli paramagnetic or diamagnetic. Regarding the possibility of lithium mobility inside the channels, of the structure, solid state 7Li NMR and high-temperature single crystal investigations revealed localization of the lithium atoms on their crystallographic sites.

  5. The BIOPAN experiment MARSTOX II of the FOTON M-3 mission

    NASA Astrophysics Data System (ADS)

    Rettberg, P.; Moeller, R.; Rabbow, E.; Panitz, C.; Horneck, G.; Meyer, C.; Lammer, H.; Douki, T.; Cadet, J.

    2008-09-01

    The experiment MARSTOX II on FOTON M-3 mission (September 14 - 26, 2007) was a further step in the study of the Responses of Organisms to the Martian Environment (ROME) which already started with first ground-based experiments in Mars simulation chambers and with the space experiment MARSTOX I, flown in 2005 in the ESA facility BIOPAN (Fig. 1) on FOTON M-2. The survivability of bacterial spores of B. subtilis, a well-characterized model system for highly resistant microorganisms, was investigated under the extreme environmental conditions as they exist on the surface of Mars. By use of exterrestrial UV radiation and cut-off filters the photoprotection and potential UV-phototoxicity of different minerals of the Martian soil were investigated.In MARSTOX II two further aspects were addressed (i) the influence of different concentrations of dust in the Martian atmosphere, which change the solar irradiance on the surface significantly compared to vacuum exposure under the same conditions (experiment parts 'DUST MARS' and 'DUST SPACE'), and (ii) the survivability of spores under martian atmosphere and pressure exposed to a mars-like spectral irradiance compared to vacuum exposure under the same conditions (experiment parts 'MIXED MARS' and 'MIXED SPACE') (Fig. 2 and 3). After exposure to space during the FOTON M-3 mission the sample analysis was performed at CEA in Grenoble, F, and at DLR in Cologne, D, together with parallel samples from the corresponding ground control experiment performed in the space simulation facilities at DLR. As biological endpoints in these investigations survival and UV-induced DNAphotoproducts were analysed.From the results of MARSTOX II the following conclusions can be drawn: (i) Spores mixed with martian soil analogue are protected only to a low degree against UV radiation. The protective effect of several defined layers of spores mixed with Martian soil analogue were quantified. (ii) The two investigated martian soil analogues, MRS07 (47

  6. Electron positron pair production at RHIC and LHC

    SciTech Connect

    Cem Gueclue, M.

    2008-11-11

    The STAR Collaboration at the Relativistic Heavy Ion Collider present data on electron-positron pair production accompanied by nuclear breakup at small impact parameters where the simultaneous excitation of the two ions, mainly the giant dipole resonance GDR, can occur. We calculate the electron-positron pair production cross section relevant for the STAR experimental setup, and compare our results with the other calculations. We have also predictions for the LHC energies.

  7. Comparison of human and porcine gastric clasp and sling fiber contraction by M2 and M3 muscarinic receptors

    PubMed Central

    Vegesna, Anil K.; Braverman, Alan S.; Miller, Larry S.; Tallarida, Ronald J.; Tiwana, Mansoor I.; Khayyam, Umar

    2010-01-01

    To compare the gastroesophageal junction of the human with the pig, M2 and M3 receptor densities and the potencies of M2 and M3 muscarinic receptor subtype selective antagonists were determined in gastric clasp and sling smooth muscle fibers. Total muscarinic and M2 receptors are higher in pig than human clasp and sling fibers. M3 receptors are higher in human compared with pig sling fibers but lower in human compared with pig clasp fibers. Clasp fibers have fewer M3 receptors than sling fibers in both humans and pigs. Similar to human clasp fibers, pig clasp fibers contract significantly less than pig sling fibers. Analysis of the methoctramine Schild plot suggests that M2 receptors are involved in mediating contraction in pig clasp and sling fibers. Darifenacin potency suggests that M3 receptors mediate contraction in pig sling fibers and that M2 and M3 receptors mediate contraction in pig clasp fibers. Taken together, the data suggest that both M2 and M3 muscarinic receptors mediate the contraction in both pig clasp and sling fibers similar to human clasp and sling fibers. PMID:20133950

  8. M3Ag17(SPh)12 Nanoparticles and Their Structure Prediction.

    PubMed

    Wickramasinghe, Sameera; Atnagulov, Aydar; Yoon, Bokwon; Barnett, Robert N; Griffith, Wendell P; Landman, Uzi; Bigioni, Terry P

    2015-09-16

    Although silver nanoparticles are of great fundamental and practical interest, only one structure has been determined thus far: M4Ag44(SPh)30, where M is a monocation, and SPh is an aromatic thiolate ligand. This is in part due to the fact that no other molecular silver nanoparticles have been synthesized with aromatic thiolate ligands. Here we report the synthesis of M3Ag17(4-tert-butylbenzene-thiol)12, which has good stability and an unusual optical spectrum. We also present a rational strategy for predicting the structure of this molecule. First-principles calculations support the structural model, predict a HOMO-LUMO energy gap of 1.77 eV, and predict a new "monomer mount" capping motif, Ag(SR)3, for Ag nanoparticles. The calculated optical absorption spectrum is in good correspondence with the measured spectrum. Heteroatom substitution was also used as a structural probe. First-principles calculations based on the structural model predicted a strong preference for a single Au atom substitution in agreement with experiment.

  9. Molecular Modeling of the M3 Acetylcholine Muscarinic Receptor and Its Binding Site

    PubMed Central

    Martinez-Archundia, Marlet; Cordomi, Arnau; Garriga, Pere; Perez, Juan J.

    2012-01-01

    The present study reports the results of a combined computational and site mutagenesis study designed to provide new insights into the orthosteric binding site of the human M3 muscarinic acetylcholine receptor. For this purpose a three-dimensional structure of the receptor at atomic resolution was built by homology modeling, using the crystallographic structure of bovine rhodopsin as a template. Then, the antagonist N-methylscopolamine was docked in the model and subsequently embedded in a lipid bilayer for its refinement using molecular dynamics simulations. Two different lipid bilayer compositions were studied: one component palmitoyl-oleyl phosphatidylcholine (POPC) and two-component palmitoyl-oleyl phosphatidylcholine/palmitoyl-oleyl phosphatidylserine (POPC-POPS). Analysis of the results suggested that residues F222 and T235 may contribute to the ligand-receptor recognition. Accordingly, alanine mutants at positions 222 and 235 were constructed, expressed, and their binding properties determined. The results confirmed the role of these residues in modulating the binding affinity of the ligand. PMID:22500107

  10. Discovery of a wide planetary-mass companion to the young M3 star GU PSC

    SciTech Connect

    Naud, Marie-Eve; Artigau, Étienne; Malo, Lison; Albert, Loïc; Doyon, René; Lafrenière, David; Gagné, Jonathan; Boucher, Anne; Saumon, Didier; Morley, Caroline V.; Allard, France; Homeier, Derek; Beichman, Charles A.; Gelino, Christopher R.

    2014-05-20

    We present the discovery of a comoving planetary-mass companion ∼42'' (∼2000 AU) from a young M3 star, GU Psc, a likely member of the young AB Doradus Moving Group (ABDMG). The companion was first identified via its distinctively red i – z color (>3.5) through a survey made with Gemini-S/GMOS. Follow-up Canada-France-Hawaii Telescope/WIRCam near-infrared (NIR) imaging, Gemini-N/GNIRS NIR spectroscopy and Wide-field Infrared Survey Explorer photometry indicate a spectral type of T3.5 ± 1 and reveal signs of low gravity which we attribute to youth. Keck/Adaptive Optics NIR observations did not resolve the companion as a binary. A comparison with atmosphere models indicates T {sub eff} = 1000-1100 K and log g = 4.5-5.0. Based on evolution models, this temperature corresponds to a mass of 9-13 M {sub Jup} for the age of ABDMG (70-130 Myr). The relatively well-constrained age of this companion and its very large angular separation to its host star will allow its thorough characterization and will make it a valuable comparison for planetary-mass companions that will be uncovered by forthcoming planet-finder instruments such as Gemini Planet Imager and SPHERE 9.

  11. M3D Simulations of Energetic Particle-driven MHD Mode with Unstructured Mesh

    NASA Astrophysics Data System (ADS)

    Fu, G. Y.; Park, W.; Strauss, H. R.

    2001-10-01

    The energetic particle-driven MHD modes are studied using a multi-level extended MHD code M3D(W. Park et al., Phys. Plasmas 6, 1796 (1999)). In a Extended-MHD model, the plasma is divided into the bulk part and the energetic particle component. The bulk plasma is treated as either a single fluid or two fluids. The energetic particles are described by gyrokinetic particles following the self-consistent electromagnetic field. The model is self-consistent, including nonlinear effects of hot particles on the MHD dynamics and the nonlinear MHD mode coupling. Previously we had shown the results of nonlinear saturation of TAEfootnote G.Y. Fu and W. Park, Phys. Rev. Lett. 74, 1594 (1995), energetic particle stabilization of an internal kink and excitation of fishbone^2, and nonlinear saturation of fishbone in circular tokamaks (G.Y. Fu et al, 2000 Sherwood Meeting, Paper 2C2.). In this work, we extend the simulations to general geometry using unstructured mesh(H.R. Strauss and W. Park, Phys. Plasmas 5, 2676 (1998). We also use a gyrofluid model for fishbone in order to study the role of MHD nonlinearity in saturation near the marginal stability. Results of applications to tokamaks and spherical tokamaks will be presented.

  12. Characterization of the microbiology within a 21 m(3)section of rock from the deep subsurface.

    PubMed

    Haldeman, D L; Amy, P S; Ringelberg, D; White, D C

    1993-09-01

    The distribution of aerobic chemoheterotrophic microorganisms within a 21 m3 section of deep subsurface rock was determined. Nineteen samples for microbiological analysis were aseptically taken by hand from the walls of a 400 m deep subsurface tunnel after an alpine miner created fresh rock faces 0.76, 1.52, 2.28, and 3.04 m into the tunnel wall. The direct counts were several orders of magnitude greater than viable counts in all samples. One of each morphologically distinct bacterial type from each sample was purified and analyzed for fatty acid methyl esters (FAME) using the Microbial Identification System (MIDI). Numbers of bacterial types, diversity, and equitability of recoverable microbial communities were the same or similar using either morphotype or FAME analyses as the basis for distinguishing between bacterial types. Twenty-nine genera (Euclidean distance of [Symbol: see text]25) were found within the rock section, while 28 of the 210 bacterial types isolated were nonculturable under the growth regime required for cluster analysis. Most isolates clustered at the genus level with Arthrobacter, Gordona, and Acinetobacter. Two genera, containing 16 isolates, were unmatched to known organisms within the MIDI data base and clustered with other isolates at a Euclidean distance greater than 50. While some species (Euclidean distance [Symbol: see text]10) were recovered from multiple sites within the rock section, most were found at 1-3 sites and usually without a definitive pattern of distribution.

  13. Conclusions of the M3D/NIMROD Cross-Code Benchmark

    NASA Astrophysics Data System (ADS)

    Breslau, J.; Park, W.; Jardin, S.; Strauss, H.; Schnack, D.; Pankin, A.

    2004-11-01

    Cross-validation of the nonlinear M3D [1] and NIMROD [2] codes in the resistive MHD regime in tokamaks has been brought to a successful conclusion. The small but well-diagnosed CDX-U device was selected for the benchmark because its low temperature (S < 10^5) is readily handled by the two codes. The test problem consisted of determining the growth rates, eigenfunctions, and nonlinear evolution of resistive internal kink modes from a base equilibrium with q_0≈ 0.92. Good agreement between the codes is observed in all three predictions. However, there is an unexpected lack of agreement between these predictions and experimental observations: whereas the 1,1 sawtooth crash in the device is a repeating phenomenon consistent with the survival of the discharge, both codes predict a spectrum of unstable resistive ballooning modes whose growth rate increases with toroidal mode number n>1, occurring near the plasma boundary and present even when q_0>1. These findings call into question the applicability of the resistive MHD model even to low temperature tokamak plasmas and suggest the need for the addition of two-fluid terms or other new physics to make accurate predictions of their behavior. [1] W. Park, et al., Phys. Plasmas 6, 1796 (1999). [2] C.R. Sovinec, et al., Phys. Plasmas 10, 1727 (2003).

  14. Light Curves for Type II Cepheids in M3 and M5

    NASA Astrophysics Data System (ADS)

    Rabidoux, K.; Smith, H. A.; Wells, K.; Randall, J.; Hartley, D.; LaCluyze, A.; De Lee, N.; Ingber, M.; Ireland, M.; KInemuchi, K.; Pellegrini, E.; Purdum, L. E.; Pritzl, B. J.; Lustig, R.; Osborn, W.; Lacy, J.; Curtis, M.; Smolinski, J.

    2005-12-01

    Many of the longer period Cepheids within globular clusters do not have modern light curves in the standard B, V, and Cousins-I photometric bandpasses. As part of a larger program to secure B, V, and I band photometry for these type II Cepheids, we have obtained CCD images of the globular clusters M3 and M5. Data were obtained with the 60-cm telescope at Michigan State University and the 40-cm telescopes at Macalester College and Central Michigan University. Light curves are presented for several Cepheids in these clusters. V84 in M5 shows evidence of alternating high and low maxima, indicative of RV Tauri behavior, and may mark the dividing line between pulsations of the type II Cepheid and RV Tauri variety. Observations have also been obtained for type II Cepheids in the globular clusters M2, M10, M12, and M13. Light curves for these variables will be used to investigate the period-luminosity relation for globular cluster Cepheids and to study their pulsational properties. This work has been supported in part by the National Science Foundation.

  15. Discovery of a Wide Planetary-mass Companion to the Young M3 Star GU Psc

    NASA Astrophysics Data System (ADS)

    Naud, Marie-Eve; Artigau, Étienne; Malo, Lison; Albert, Loïc; Doyon, René; Lafrenière, David; Gagné, Jonathan; Saumon, Didier; Morley, Caroline V.; Allard, France; Homeier, Derek; Beichman, Charles A.; Gelino, Christopher R.; Boucher, Anne

    2014-05-01

    We present the discovery of a comoving planetary-mass companion ~42'' (~2000 AU) from a young M3 star, GU Psc, a likely member of the young AB Doradus Moving Group (ABDMG). The companion was first identified via its distinctively red i - z color (>3.5) through a survey made with Gemini-S/GMOS. Follow-up Canada-France-Hawaii Telescope/WIRCam near-infrared (NIR) imaging, Gemini-N/GNIRS NIR spectroscopy and Wide-field Infrared Survey Explorer photometry indicate a spectral type of T3.5 ± 1 and reveal signs of low gravity which we attribute to youth. Keck/Adaptive Optics NIR observations did not resolve the companion as a binary. A comparison with atmosphere models indicates T eff = 1000-1100 K and log g = 4.5-5.0. Based on evolution models, this temperature corresponds to a mass of 9-13 M Jup for the age of ABDMG (70-130 Myr). The relatively well-constrained age of this companion and its very large angular separation to its host star will allow its thorough characterization and will make it a valuable comparison for planetary-mass companions that will be uncovered by forthcoming planet-finder instruments such as Gemini Planet Imager and SPHERE.

  16. Radiation environment on board Foton-M 3: the neutron component

    NASA Astrophysics Data System (ADS)

    Falzetta, Giuseppe; Zanini, Alba; Chiorra, Katia; Briccarello, Mauro; Belluco, Maurizio; Longo, Francesco; Jerse, Giovanna

    The recoverable capsule Foton-M 3 (ESA mission) was launched from Baikonur on 2007 September 14 and landed on the Russian-Kazakh border 12 days later. The spacecraft carried on board several ESA experiments. During this space mission a study has been performed on the neutron component of the radiation environment inside the capsule. Neutrons are a not avoidable component of the secondary radiation produced by interaction of primary radiation with the spacecraft shielding. Because of their high LET, neutrons could represent a main risk for both the electronic instruments and the health of the astronauts during space missions. Monte Carlo simulations performed by Geant4 code have been carried out using as input primary proton and alpha spectra, obtained by various tools (i.e. Creme 96, Omere, etc . . . ) and the neutron fluxes and doses, as a function of neutron energies, have been evaluated. The simulation results are compared with experimental data obtained by passive neutron detectors. In this study the effectiveness of various shielding materials useful in space mission has been also investigated.

  17. Frustrated Cooper pairing and f-wave supersolidity in cold-atom optical lattices

    SciTech Connect

    Hung, Hsiang-Hsuan; Lee, Wei-Cheng; Wu Congjun

    2011-04-01

    Geometric frustration in quantum magnetism refers to the fact that magnetic interactions on different bonds cannot be simultaneously minimized. The usual Cooper pairing systems favor uniform spatial distributions of pairing phases among different lattice sites without frustration. In contrast, we propose ''frustrated Cooper pairing'' in non-bipartite lattices which leads to supersolid states of Cooper pairs. Not only the amplitudes of the pairing order parameter but also its signs vary from site to site. This exotic pairing state naturally occurs in the p-orbital bands in optical lattices with ultracold spinless fermions. In the triangular lattice, it exhibits an unconventional supersolid state with the f-wave symmetry.

  18. Pairing Correlations at High Spins

    NASA Astrophysics Data System (ADS)

    Ma, Hai-Liang; Dong, Bao-Guo; Zhang, Yan; Fan, Ping; Yuan, Da-Qing; Zhu, Shen-Yun; Zhang, Huan-Qiao; Petrache, C. M.; Ragnarsson, I.; Carlsson, B. G.

    The pairing correcting energies at high spins in 161Lu and 138Nd are studied by comparing the results of the cranked-Nilsson-Strutinsky (CNS) and cranked-Nilsson-Strutinsky-Bogoliubov (CNSB) models. It is concluded that the Coriolis effect rather than the rotational alignment effect plays a major role in the reduction of the pairing correlations in the high spin region. Then we proposed an average pairing correction method which not only better reproduces the experimental data comparing with the CNS model but also enables a clean-cut tracing of the configurations thus the full-spin-range discussion on the various rotating bands.

  19. Pairing Properties of Superheavy Nuclei

    SciTech Connect

    Staszczak, A.; Dobaczewski, J.; Nazarewicz, Witold

    2007-01-01

    Pairing properties of even-even superheavy N=184 isotones are studied within the Skyrme-Hartree-Fock+BCS approach. In the particle-hole channel we take the Skyrme energy density functional SLy4, while in the particle-particle channel we employ the seniority pairing force and zero-range delta-interactions with different forms of density dependence. We conclude that the calculated static fission trajectories weakly depend on the specific form of the delta-pairing interaction. We also investigate the impact of triaxiality on the inner fission barrier and find a rather strong Z dependence of the effect.

  20. Neutron-proton pairing correlations in odd mass systems

    SciTech Connect

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

    2015-03-30

    An expression of the ground-state which describes odd mass systems within the BCS approach in the isovector neutron-proton pairing case is proposed using the blocked level technique. The gap equations as well as the energy expression are then derived. It is shown that they exactly generalize the expressions obtained in the pairing between like-particles case. The various gap parameters and the energy are then numerically studied as a function of the pairing-strength within the schematic one-level model.

  1. Extension of RAPTOR-M3G to r-θ-z Geometry for Use in Reactor Dosimetry Applications

    NASA Astrophysics Data System (ADS)

    Hunter, Melissa A.; Longoni, Gianluca; Anderson, Stanwood L.

    2009-08-01

    The RAPTOR-M3G (RApid Parallel Transport Of Radiation - Multiple 3-D Geometries) is a new deterministic radiation transport code that was originally developed for x-y-z geometry. The development of the r-θ-z version of RAPTOR-M3G and its application to determine ex-vessel neutron dosimetry responses in the cavity of a typical 2-loop pressurized water reactor is presented. The neutron dosimetry responses determined from RAPTOR-M3G and TORT 3-D r-θ-z calculations are compared to actual measured responses.

  2. Matched molecular pair analysis in drug discovery.

    PubMed

    Dossetter, Alexander G; Griffen, Edward J; Leach, Andrew G

    2013-08-01

    Multiple parameter optimisation in drug discovery is difficult, but Matched Molecular Pair Analysis (MMPA) can help. Computer algorithms can process data in an unbiased way to yield design rules and suggest better molecules, cutting the number of design cycles. The approach often makes more suggestions than can be processed manually and methods to deal with this are proposed. However, there is a paucity of contextually specific design rules, which would truly make the technique powerful. By combining extracted information from multiple sources there is an opportunity to solve this problem and advance medicinal chemistry in a matter of months rather than years. PMID:23557664

  3. Dynamical interactions of galaxy pairs

    NASA Technical Reports Server (NTRS)

    Athanassoula, E.

    1990-01-01

    Here the author briefly reviews the dynamics of sinking satellites and the effect of companions on elliptical galaxies. The author then discusses recent work on interacting disk systems, and finally focuses on a favorite interacting pair, NGC 5194/5195.

  4. Pair Excitations in Fermi Fluids

    NASA Astrophysics Data System (ADS)

    Böhm, Helga M.; Krotscheck, Eckhard; Schörkhuber, Karl; Springer, Josef

    2006-09-01

    We present a theory of multi-pair excitations in strongly interacting Fermi systems. Based on an equations-of-motion approach for time-dependent pair correlations it leads to a qualitatively new structure of the density-density response function. Our theory reduces to both, i) the "correlated" random-phase approximation (RPA) for fermions if the two-pair excitations are ignored, and ii) the correlated Brillouin-Wigner perturbation theory for bosons in the appropriate limit. The theory preserves the two first energy-weighted sum rules. A familiar problem of the standard RPA is that its zero-sound mode is energetically much higher than found in experiments. The popular cure of introducing an average effective mass in the Lindhard function violates sum rules and describes the physics incorrectly. We demonstrate that the inclusion of correlated pair excitations gives the correct dispersion. As in 4He, a modification of the effective mass is unnecessary also in 3He.

  5. Mineralogy of young lunar mare basalts: Assessment of temporal and spatial heterogeneity using M3 data from Chandrayaan-1

    NASA Astrophysics Data System (ADS)

    Varatharajan, Indhu; Srivastava, Neeraj; Murty, Sripada V. S.

    2014-07-01

    A comparative assessment of the mineralogy of young basalts (∼1.2 Ga to ∼2.8 Ga) from the western nearside, Moscoviense basin, and the Orientale basin of the Moon has been made using Level 2 Moon Mineralogy Mapper (M3) data from the Chandrayaan-1 mission. Spectral data characteristics of the individual units have been generated from fresh small craters to minimize the complications due to space weathering. Representative spectra for individual units and the derived spectral parameters (band centers and integrated band depth ratio) have been used to study composition of these young basalts. A modified approach of Gaffey et al. (Gaffey, M.J., Cloutis, E.A., Kelley, M.S., Reed, K.L. [2002]. Mineralogy of asteroids. In: Asteroids III. The University of Arizona Press, Tucson, pp. 183-204) (for olivine-pyroxene mixtures) and the methodology of Adams (Adams, J.B. [1974]. J. Geophys. Res. 79, 4829-4836. http://dx.doi.org/10.1029/JB079i032p04829) (for interpreting pyroxene type) have been used to improve our understanding of the spectral behavior of these basalts. Most of the young basalts of Oceanus Procellarum are characterized by abundant olivines and they show complex volcanic history. Vast exposures of olivine concentrated units having higher abundance of olivine content than high-Ca pyroxenes are emplaced in the northern Oceanus Procellarum region. Mostly, they show distinct stratigraphic gradation with the immediately underlying units of relatively lower olivine content. The Moscoviense unit shows signatures of Fe-rich glasses along with clinopyroxenes. The basalts of Orientale basin are typically devoid of olivine and are rich in high-Ca pyroxene. Thus, mineralogy of these mare basalts which erupted during the late stage volcanism vary across the Moon’s surface; however, broader observations reveal apparently higher FeO content in the younger basalts of western nearside and Orientale region.

  6. Fabry-Perot Velocities For Globular Cluster Stars: M15, M3, and M4

    NASA Astrophysics Data System (ADS)

    Gebhardt, Karl; Pryor, Carlton; Williams, T. B.; Hesser, James E.

    1994-12-01

    We are engaged in a continuing project that uses an imaging Fabry-Perot spectrophotometer on the 3.6-m CFHT and the 4 m and 1.5 m telescopes at CTIO to measure both absorption-line integrated-light velocity maps for globular clusters and velocities for large samples of cluster stars (Gebhardt, K., Pryor, C., Williams, T.B., & Hesser, J.E. 1994, AJ, 107, 2067; Gebhardt, et al. 1994, submitted). Our goals are to study such kinematic properties as rotation and the number of high-velocity stars, and to use the velocity dispersion profiles to determine non-parametric mass profiles using the technique of Gebhardt & Fischer (1995, January AJ). Here we present radial velocities with accuracies of 1--5 \\kms\\ for about 600 stars in the cusp cluster M15, 400 stars in the centrally-concentrated cluster M3, and 1900 stars in the nearby cluster M4. The M15 dataset contains three times more stellar velocities throughout the whole cluster and five times more in the inner 10'' than the previous study of Gebhardt & Fischer. This larger sample continues to show no evidence for a central cusp in the velocity dispersion profile. The M4 data constitute one of the largest radial velocity samples yet obtained for a globular cluster. The stars in the sample range from magnitude V=10 to V=18.5. V=18.5 is 2.5 magnitudes below the main-sequence turn-off, so these data are valuable first-epoch information for determining the main-sequence binary fraction. We present two-dimensional velocity maps, velocity dispersion profiles, and radial mass profiles for the three clusters.

  7. MAGNETIC AND DYNAMICAL PHOTOSPHERIC DISTURBANCES OBSERVED DURING AN M3.2 SOLAR FLARE

    SciTech Connect

    Kuckein, C.; Collados, M.; Sainz, R. Manso

    2015-02-01

    This Letter reports on a set of full-Stokes spectropolarimetric observations in the near-infrared He i 10830 Å spectral region covering the pre-flare, flare, and post-flare phases of an M3.2 class solar flare. The flare originated on 2013 May 17 and belonged to active region NOAA 11748. We detected strong He i 10830 Å emission in the flare. The red component of the He i triplet peaks at an intensity ratio to the continuum of about 1.86. During the flare, He i Stokes V is substantially larger and appears reversed compared to the usually larger Si i Stokes V profile. The photospheric Si i inversions of the four Stokes profiles reveal the following: (1) the magnetic field strength in the photosphere decreases or is even absent during the flare phase, as compared to the pre-flare phase. However, this decrease is not permanent. After the flare, the magnetic field recovers its pre-flare configuration in a short time (i.e., 30 minutes after the flare). (2) In the photosphere, the line of sight velocities show a regular granular up- and downflow pattern before the flare erupts. During the flare, upflows (blueshifts) dominate the area where the flare is produced. Evaporation rates of ∼10{sup −3} and ∼10{sup −4} g cm{sup −2} s{sup −1} have been derived in the deep and high photosphere, respectively, capable of increasing the chromospheric density by a factor of two in about 400 s.

  8. Signal transduction by M3 muscarinic acetylcholine receptor in prostate cancer

    PubMed Central

    GUO, LIQIANG; LIU, YUQIANG; DING, ZHIBO; SUN, WENDONG; YUAN, MINGZHEN

    2016-01-01

    The present study aimed to investigate the potential mechanisms used during signal transduction by M3 muscarinic acetylcholine receptor (CHRM3) in prostate cancer. The microarray datasets of GSE3325, including 5 clinically localized primary prostate cancers and 4 benign prostate tissues, were downloaded from the Gene Expression Omnibus database. The differentially-expressed genes (DEGs) in primary prostate cancer tissues compared with benign controls were screened using the Limma package. Gene Ontology and pathway enrichment analyses were performed using the Database for Annotation Visualization and Integrated Discovery. Next, a protein-protein interaction (PPI) network was constructed. Additionally, microRNAs (miRNAs) associated with DEGs were predicted and miRNA-target DEG analysis was performed using a Web-based Gene Set Analysis Toolkit. Finally, the PPI network and the miRNA-target DEG network were integrated using Cytoscape. In total, 224 DEGs were screened in the prostate cancer tissues, including 113 upregulated and 111 downregulated genes. CHRM3 and epidermal growth factor (EGF) were enriched in the regulation of the actin cytoskeleton. EGF and v-myc avian myelocytomatosis viral oncogene homolog (Myc) were enriched in the mitogen-activated protein kinase (MAPK) signaling pathway. EGF with the highest degree of connectivity was the hub node in the PPI network, and miR-34b could interact with Myc directly in the miRNA-target DEG network. EGF and Myc may exhibit significant roles in the progression of prostate cancer via regulation of the actin cytoskeleton and the MAPK signaling pathway. CHRM3 may activate these two pathways in prostate cancer progression. Thus, these two key factors and pathways may be crucial mechanisms during signal transduction by CHRM3 in prostate cancer. PMID:26870222

  9. Remote compositional analysis of lunar olivine-rich lithologies with Moon Mineralogy Mapper (M3) spectra

    USGS Publications Warehouse

    Isaacson, P.J.; Pieters, C.M.; Besse, S.; Clark, R.N.; Head, J.W.; Klima, R.L.; Mustard, J.F.; Petro, N.E.; Staid, M.I.; Sunshine, J.M.; Taylor, L.A.; Thaisen, K.G.; Tompkins, S.

    2011-01-01

    A systematic approach for deconvolving remotely sensed lunar olivine-rich visible to near-infrared (VNIR) reflectance spectra with the Modified Gaussian Model (MGM) is evaluated with Chandrayaan-1 Moon Mineralogy Mapper (M 3) spectra. Whereas earlier studies of laboratory reflectance spectra focused only on complications due to chromite inclusions in lunar olivines, we develop a systematic approach for addressing (through continuum removal) the prominent continuum slopes common to remotely sensed reflectance spectra of planetary surfaces. We have validated our continuum removal on a suite of laboratory reflectance spectra. Suites of olivine-dominated reflectance spectra from a small crater near Mare Moscoviense, the Copernicus central peak, Aristarchus, and the crater Marius in the Marius Hills were analyzed. Spectral diversity was detected in visual evaluation of the spectra and was quantified using the MGM. The MGM-derived band positions are used to estimate the olivine's composition in a relative sense. Spectra of olivines from Moscoviense exhibit diversity in their absorption features, and this diversity suggests some variation in olivine Fe/Mg content. Olivines from Copernicus are observed to be spectrally homogeneous and thus are predicted to be more compositionally homogeneous than those at Moscoviense but are of broadly similar composition to the Moscoviense olivines. Olivines from Aristarchus and Marius exhibit clear spectral differences from those at Moscoviense and Copernicus but also exhibit features that suggest contributions from other phases. If the various precautions discussed here are weighed carefully, the methods presented here can be used to make general predictions of absolute olivine composition (Fe/Mg content). Copyright ?? 2011 by the American Geophysical Union.

  10. Study of the continuum removal method for the Moon Mineralogy Mapper (M3) and its application to Mare Humorum and Mare Nubium

    NASA Astrophysics Data System (ADS)

    Zhang, Xun-Yu; Ouyang, Zi-Yuan; Zhang, Xiao-Meng; Chen, Yuan; Tang, Xiao; Xu, Ao-Ao; Tang, Ze-Sheng; Wu, Yun-Zhao

    2016-07-01

    The absorption band center of visible and near infrared reflectance spectra is a key spectral parameter for lunar mineralogical studies, especially for the mafic minerals (olivine and pyroxene) of mare basalts, which have two obvious absorption bands at 1000 nm (Band I) and 2000nm (Band II). Removal of the continuum from spectra, which was developed by Clark and Roush and used to isolate the particular absorption feature, is necessary to estimate this parameter. The Moon Mineralogy Mapper (M3) data are widely used for lunar mineral identification. However, M3 data show a residual thermal effect, which interferes with the continuum removal, and systematic differences exist among optical data taken during different optical periods. This study investigated a suitable continuum removal method and compared the difference between two sets of M3 data taken during different optical periods, Optical Period 1B (OP1B) and Optical Period 2A (OP2A). Two programs for continuum removal are reported in this paper. Generally, a program respectively constructs two straight lines across Band I and Band II to remove the continuum, which is recommended for locating band centers, because it can find the same Band I center with different right endpoints. The optimal right endpoint for continuum removal is mainly dominated by two optical period data at approximately 2480 and 2560nm for OP1B and OP2A data, respectively. The band center values derived from OP1B data are smaller than those derived from OP2A data in Band I but larger in Band II, especially for the spectra using longer right endpoints (>2600 nm). This may be due to the spectral slopes of OP1B data being steeper than those of OP2A data in Band I but gentler in Band II. These results were applied to Mare Humorum and Mare Nubium, and the measurements were found to mainly vary from intermediate- to high-Ca pyroxene.

  11. New Halo Stars of the Galactic Globular Clusters M3 and M13 in the LAMOST DR1 Catalog

    NASA Astrophysics Data System (ADS)

    Navin, Colin A.; Martell, Sarah L.; Zucker, Daniel B.

    2016-10-01

    M3 and M13 are Galactic globular clusters with previous reports of surrounding stellar halos. We present the results of a search for members and extratidal cluster halo stars within and outside of the tidal radius of these clusters in the LAMOST Data Release 1. We find seven candidate cluster members (inside the tidal radius) of both M3 and M13, respectively. In M3 we also identify eight candidate extratidal cluster halo stars at distances up to ∼9.8 times the tidal radius, and in M13 we identify 12 candidate extratidal cluster halo stars at distances up to ∼13.8 times the tidal radius. These results support previous indications that both M3 and M13 are surrounded by extended stellar halos, and we find that the GC destruction rates corresponding to the observed mass loss are generally significantly higher than theoretical studies predict.

  12. Non-Ideal ELM Stability and Non-Axisymmetric Field Penetration Calculations with M3D-C1

    NASA Astrophysics Data System (ADS)

    Ferraro, N. M.; Chu, M. S.; Snyder, P. B.; Jardin, S. C.; Luo, X.

    2009-11-01

    Numerical studies of ELM stability and non-axisymmetric field penetration in diverted DIII-D and NSTX equilibria are presented, with resistive and finite Larmor radius effects included. These results are obtained with the nonlinear two-fluid code M3D-C1, which has recently been extended to allow linear non-axisymmetric calculations. Benchmarks of M3D-C1 with ideal codes ELITE and GATO show good agreement for the linear stability of peeling-ballooning modes in the ideal limit. New calculations of the resistive stability of ideally stable DIII-D equilibria are presented. M3D-C1 has also been used to calculate the linear response to non-axisymmetric external fields; these calculations are benchmarked with Surfmn and MARS-F. New numerical methods implemented in M3D-C1 are presented, including the treatment of boundary conditions with C^1 elements in a non-rectangular mesh.

  13. Superconductivity: The persistence of pairs

    SciTech Connect

    Edelman, Alex; Littlewood, Peter

    2015-05-20

    Superconductivity stems from a weak attraction between electrons that causes them to form bound pairs and behave much like bosons. These so-called Cooper pairs are phase coherent, which leads to the astonishing properties of zero electrical resistance and magnetic flux expulsion typical of superconducting materials. This coherent state may be qualitatively understood within the Bose–Einstein condensate (BEC) model, which predicts that a gas of interacting bosons will become unstable below a critical temperature and condense into a phase of matter with a macroscopic, coherent population in the lowest energy state, as happens in 4He or cold atomic gases. The successful theory proposed by Bardeen, Cooper and Schrieffer (BCS) predicts that at the superconducting transition temperature Tc, electrons simultaneously form pairs and condense, with no sign of pairing above Tc. Theorists have long surmised that the BCS and BEC models are opposite limits of a single theory and that strong interactions or low density can, in principle, drive the system to a paired state at a temperature Tpair higher than Tc, making the transition to the superconducting state BEC-like (Fig. 1). Yet most superconductors to date are reasonably well described by BCS theory or its extensions, and there has been scant evidence in electronic materials for the existence of pairing independent of the full superconducting state (though an active debate rages over the cuprate superconductors). Writing in Nature, Jeremy Levy and colleagues have now used ingenious nanostructured devices to provide evidence for electron pairing1. Perhaps surprisingly, the material they have studied is a venerable, yet enigmatic, low-temperature superconductor, SrTiO3.

  14. Improving the Apollo 12 landing site mapping with Chandrayaan M3 data

    NASA Astrophysics Data System (ADS)

    Chemin, Yann; Crawford, Ian; Bugiolacchi, Roberto; Irfan, Huma; Alexander, Louise

    2014-05-01

    The geology of the Apollo 12 landing site has been the subject of many studies, including recently by Korotev et al. (2011) and Snape et al. (2013). This research attempts to bring additional understanding from a remote sensing perspective using the Moon Mineralogy Mapper (M3) sensor data, onboard the Chandrayaan lunar orbiter. This has a higher spatial-spectral resolution sensor than the Clementine UV-Vis sensor and provides the opportunity to study the lunar surface with detailed spectral signatures. Mapping of FeO (wt%) and TiO2 (wt%) is done using the methods of Lucey et al. (2000) and Wilcox et al. (2005). A FeO & TiO2 processing module (i.feotio2) is made specifically for this research within the Free & Open Source Software GRASS GIS. Attempts will be made to estimate the lava flow thickness using the method of Bugiolacchi et al. (2006) and individual lava layers thicknesses (Weider et al., 2010). Integration of this new information will be put in perspective and integrated with previous work. Analysis from the combined higher spatial and spectral resolutions will improve the accuracy of the geological mapping at the Apollo 12 landing site. References Bugiolacchi, R., Spudis, P.D., Guest, J.E., 2006. Stratigraphy and composition of lava flows in Mare Nubium and Mare Cognitum. Meteoritics & Planetary Science. 41(2):285-304. Korotev, R.L., Jolliff, B.L., Zeigler, R.A., Seddio, S.M., Haskin, L.A., 2011. Apollo 12 revisited. Geochimica et Cosmochimica Acta. 75(6):1540-1573. Lucey, P.G., Blewett, D.T., Jolliff, B.L., 2000. Lunar iron and titanium abundance algorithms based on final processing of Clementine ultraviolet-visible images. J. Geophys. Res. 105(E8): 20297-20305. Snape, J.F., Alexander, L., Crawford, I.A., Joy, K.H., 2013. Basaltic Regolith Sample 12003,314: A New Member of the Apollo 12 Feldspathic Basalt Suite? Lunar and Planetary Institute Science Conference Abstracts 44:1044. Weider, S.Z., Crawford, I.A. and Joy, K.H., "Individual lava flow

  15. Peculiarities of lens and tail regeneration detected in newts after spaceflight aboard Foton M3

    NASA Astrophysics Data System (ADS)

    Grigoryan, Eleonora N.; Almeida, Eduardo; Poplinskaya, Valentina; Novikova, Julia; Domaratskaya, Elena; Aleinikova, Karina; Souza, Kenneth; Skidmore, Mike; Grigoryan, Eleonora N.

    In September 2007 the joint, 12 day long experiment was carried out aboard Russian satellite Foton M3. The goal of the experiment was to study eye lens, tail and forelimb toe regeneration in adult 16 newts (Pl. waltl.) operated 10 days before taking-off. In spaceflight and synchronous ground control we used video recording, temperature and irradiation control, as well as constant availability of thymidine analog BrdU for its absorption via animals' skin. New techniques allowed us to analyze animals' behavior in hyperand microgravity periods of time, to take proper account of spaceflight factors, and measure accumulated pools of DNA-synthesizing cells in regenerating tissues. All tissue specimens obtained from animals were isolated in the day of landing and then prepared for morphological, immunochemical and molecular investigations. Synchronous control was shifted for two days and reproduced flight conditions except changes of gravity influence. As a result in flown animals as compared with synchronous ground control we found lens regeneration of 0.5-1 stage speeded up and an increased BrdU+ (S-phase) cell number in eye cornea, growth zone, limbus and newly forming lens. These features of regeneration were accompanied by an increase of FGF2 expression in eye growth zone and heat shock protein (HSP90) induction purely in retinal macroglial cells of regenerating eyes. Toe regeneration rate was equal and achieved the stage of accomplished healing of amputation area in both groups - "flown" and control animals. We found no essential differences in tail regeneration rate and tail regenerate sizes in the newts exposed to space and on ground. In both groups tail regeneration reached the stage IV-V when tail length and square were around 4.4 mm and 15.5 mm2, correspondingly. However we did observe remarkable changes of tail regenerate form and some of pigmentation. Computer morphometrical analysis showed that only in ground control animals the evident dorso

  16. Origin of Aristarchus Olivine Deposits Based on M3, WAC, and Diviner Analyses

    NASA Astrophysics Data System (ADS)

    Wiseman, S. M.; Mustard, J. F.; Donaldson Hanna, K. L.; Isaacson, P.; Jolliff, B. L.; Besse, S.; Staid, M.; Pieters, C. M.

    2011-12-01

    The Aristarchus region contains geologically diverse deposits and the Aristarchus impact crater, located on the SE margin of the plateau near the contact between plateau materials and western Procellarum basalts, has exposed materials with variable compositions. Of particular interest is the origin of olivine-bearing deposits that occur on the SE portion of the crater rim and ejecta in association with impact melt [1]. NW portions of the rim and ejecta expose plateau materials and are spectrally dominated by pyroxene in the VNIR. Spectra of the NW rim and ejecta are consistent with a noritic composition and with the inferred origin of the plateau as uplifted upper crust [2,3,4]. Therefore, it is unlikely that the olivine- bearing materials, which exhibit a strong 1 micron olivine absorption and only minor pyroxene contributions, are derived from plateau materials similar to those exposed in the NW portion of the crater. Potential sources of the olivine-bearing material excavated by the impact include western Procellarum basalts or buried material associated with the Marius Hills volcanic complex. Alternatively, the olivine-bearing deposits could be derived from a shallow pluton that is not represented by other surface exposures or could have formed as re-crystallized impact melt. Both the western Procellarum basalts [5,6] and some units associated with the Marius Hills [7] are olivine-bearing. In order to differentiate between these hypotheses, we are integrating spectral data in the UV/VIS (LRO WAC), VIS/NIR (Chandrayaan-1 M3), and TIR (LRO Diviner) to further characterize the assemblages of minerals that occur in association with the olivine-bearing deposits in Aristarchus crater, western Procellarum, and units within the Marius Hills volcanic complex. [1] Mustard et al., 2011, JGR 116. [2] McEwen et al., 1994, Science 266. [3] Lucey et al., 1986, LPSC 16. [4] Chevrel et al., 2009, Icarus 199. [5] Staid and Pieters 2001, JGR. [6] Staid et al., 2011, JGR 116. [7

  17. Pair extended coupled cluster doubles

    SciTech Connect

    Henderson, Thomas M.; Scuseria, Gustavo E.; Bulik, Ireneusz W.

    2015-06-07

    The accurate and efficient description of strongly correlated systems remains an important challenge for computational methods. Doubly occupied configuration interaction (DOCI), in which all electrons are paired and no correlations which break these pairs are permitted, can in many cases provide an accurate account of strong correlations, albeit at combinatorial computational cost. Recently, there has been significant interest in a method we refer to as pair coupled cluster doubles (pCCD), a variant of coupled cluster doubles in which the electrons are paired. This is simply because pCCD provides energies nearly identical to those of DOCI, but at mean-field computational cost (disregarding the cost of the two-electron integral transformation). Here, we introduce the more complete pair extended coupled cluster doubles (pECCD) approach which, like pCCD, has mean-field cost and reproduces DOCI energetically. We show that unlike pCCD, pECCD also reproduces the DOCI wave function with high accuracy. Moreover, pECCD yields sensible albeit inexact results even for attractive interactions where pCCD breaks down.

  18. Spectroscopy of asteroid pairs - new observations support previous conclusions

    NASA Astrophysics Data System (ADS)

    Polishook, David; Oszkiewicz, Dagmara Anna; None Kwiatkowski, Tomasz

    2015-08-01

    Asteroid pairs were split due to fast rotation of a strengthless body. Study them can reveal fundamental principles in asteroid interiors and evolution. We continue our spectroscopic survey of asteroid pairs in the near-IR range (IRTF) and work on completing the spectral coverage in the visible wavelength (SALT, NOT).Our new observations support our previous conclusions (Polishook et al. 2014):1. Primary and secondary members have very similar reflectance spectra supporting the claim that every pair originated from a single progenitor. We measured 2 more pairs that present the same taxonomy (4905-7813, 15107-291188). This increases to 22 the number of asteroid pairs with spectral similarities and supports the claim of a single progenitor for each pair to a significance of over 5 sigma.2. Rotational fission is not a function of the asteroid composition rather the asteroid’s structure. We present new reflectance spectra of S- and C-complex pairs that differ in their composition.3. Some asteroid pairs present spectral parameters that imply a fresh, non-weathered surface. This includes spectral slope, and a deep and wide absorption band at 1 micron. Among these, the asteroid 8306 can now be re-classified as a Q-type asteroid, a common class in the near-Earth environment, but rare in the main belt. 8306 is the 4th Q-type discovered within asteroid pairs (all locate in the main belt).4. A secondary member of an asteroid pair composed of ordinary chondrite (S-complex) might present a reflectance spectrum with lower spectral slope compared to its primary member. This is seen in the new measured reflectance spectrum of secondary 291188). This result supports the theory of Jacobson & Scheeres (2011) of continuous disintegration of the secondaries while still in the vicinity of their primaries.5. With time, the fresh surface becomes weathered. Dynamical calculations limit the disintegration time of the progenitor of the pair 4905-7813 to 1.65 millions years ago, what makes

  19. Pair-Starved Pulsar Magnetospheres

    NASA Technical Reports Server (NTRS)

    Muslimov, Alex G.; Harding, Alice K.

    2009-01-01

    We propose a simple analytic model for the innermost (within the light cylinder of canonical radius, approx. c/Omega) structure of open-magnetic-field lines of a rotating neutron star (NS) with relativistic outflow of charged particles (electrons/positrons) and arbitrary angle between the NS spin and magnetic axes. We present the self-consistent solution of Maxwell's equations for the magnetic field and electric current in the pair-starved regime where the density of electron-positron plasma generated above the pulsar polar cap is not sufficient to completely screen the accelerating electric field and thus establish thee E . B = 0 condition above the pair-formation front up to the very high altitudes within the light cylinder. The proposed mode1 may provide a theoretical framework for developing the refined model of the global pair-starved pulsar magnetosphere.

  20. Theoretical study of nascent solvation in Ni+ (benzene)m, m = 3 and 4, clusters.

    PubMed

    Castro, Miguel; Flores, Raul; Duncan, Michael A

    2013-11-27

    The ligand versus solvent behavior of Ni(+)(C6H6)3,4 complexes was studied using density functional theory all-electron calculations. Dispersion corrections were included with the BPW91-D2 method using the 6-311++G(2d,2p) basis set. The ground state (GS) for Ni(+)(C6H6)3 has three benzene rings 3d-π bonded to the metal. A two-layer isomer with two moieties coordinated η(3)-η(2) with Ni(+), and the other one adsorbed by van der Waals interactions to the Ni(+)(C6H6)2 subcluster, i.e., a 2 + 1 structure, is within about 8.4 kJ/mol of the GS. Structures with 3 + 1 and 2 + 2 ligand coordination were found for Ni(+)(C6H6)4. The binding energies (D0) of 28.9 and 26.0 kJ/mol for the external moieties of Ni(+)(C6H6)3,4 are much smaller than that for Ni(+)(C6H6)2, 193.0 kJ/mol, obtained also with BPW91-D2. This last D0 overestimates somehow the experimental value, of 146.7 ± 11.6 kJ/mol, for Ni(+)(C6H6)2. The abrupt fall for D0(Ni(+)(C6H6)3,4) shows that such molecules are bound externally as solvent species. These results agree with the D0(Ni(+)(C6H6)3) < 37.1 kJ/mol limit found experimentally for this kind of two-layer clusters. The ionization energies also decrease for m = 2, 3, and 4 (580.8, 573.1, and 558.6 kJ/mol). For Ni(+)(C6H6)3,4, each solvent moiety bridges the benzenes of Ni(+)(C6H6)2; their position and that of one internal ring mimics the tilted T-shape geometry of the benzene dimer (Bz2). The distances from the center of the external to the center of the internal rings for m = 3 (4.686 Å) and m = 4 (4.523 Å) are shorter than that for Bz2 (4.850 Å). This and charge transfer effects promote the (C(δ-)-H(δ+))(int) dipole-π(ext) interactions in Ni(+)(C6H6)3,4; π-π interactions also occur. The predicted IR spectra, having multiplet structure in the C-H region, provide insight into the experimental spectra of these ions. PMID:24218987

  1. ON THE POLAR CAP CASCADE PAIR MULTIPLICITY OF YOUNG PULSARS

    SciTech Connect

    Timokhin, A. N.; Harding, A. K.

    2015-09-10

    We study the efficiency of pair production in polar caps of young pulsars under a variety of conditions to estimate the maximum possible multiplicity of pair plasma in pulsar magnetospheres. We develop a semi-analytic model for calculation of cascade multiplicity which allows efficient exploration of the parameter space and corroborate it with direct numerical simulations. Pair creation processes are considered separately from particle acceleration in order to assess different factors affecting cascade efficiency, with acceleration of primary particles described by recent self-consistent non-stationary model of pair cascades. We argue that the most efficient cascades operate in the curvature radiation/synchrotron regime, the maximum multiplicity of pair plasma in pulsar magnetospheres is ∼few × 10{sup 5}. The multiplicity of pair plasma in magnetospheres of young energetic pulsars weakly depends on the strength of the magnetic field and the radius of curvature of magnetic field lines and has a stronger dependence on pulsar inclination angle. This result questions assumptions about very high pair plasma multiplicity in theories of pulsar wind nebulae.

  2. Applicability of effective pair potentials for active Brownian particles.

    PubMed

    Rein, Markus; Speck, Thomas

    2016-09-01

    We have performed a case study investigating a recently proposed scheme to obtain an effective pair potential for active Brownian particles (Farage et al., Phys. Rev. E 91, 042310 (2015)). Applying this scheme to the Lennard-Jones potential, numerical simulations of active Brownian particles are compared to simulations of passive Brownian particles interacting by the effective pair potential. Analyzing the static pair correlations, our results indicate a limited range of activity parameters (speed and orientational correlation time) for which we obtain quantitative, or even qualitative, agreement. Moreover, we find a qualitatively different behavior for the virial pressure even for small propulsion speeds. Combining these findings we conclude that beyond linear response active particles exhibit genuine non-equilibrium properties that cannot be captured by effective pair interaction alone. PMID:27628695

  3. Muscarinic Acetylcholine Receptor M3 Modulates Odorant Receptor Activity via Inhibition of β-Arrestin-2 Recruitment

    PubMed Central

    Jiang, Yue; Li, Yun Rose; Tian, Huikai; Ma, Minghong; Matsunami, Hiroaki

    2015-01-01

    The olfactory system in rodents serves a critical function in social, reproductive, and survival behaviors. Processing of chemosensory signals in the brain is dynamically regulated in part by an animal's physiological state. We previously reported that type 3 muscarinic acetylcholine receptors (M3-Rs) physically interact with odorant receptors (ORs) to promote odor-induced responses in a heterologous expression system. However, it is not known how M3-Rs affect the ability of olfactory sensory neurons (OSNs) to respond to odors. Here, we show that an M3-R antagonist attenuates odor-induced responses in OSNs from wild-type, but not M3-R-null mice. Using a novel molecular assay, we demonstrate that the activation of M3-Rs inhibits the recruitment of β-arrestin-2 to ORs, resulting in a potentiation of odor-induced response in OSNs. These results suggest a role for acetylcholine in modulating olfactory processing at the initial stages of signal transduction in the olfactory system. PMID:25800153

  4. Hypocholesterolemic effects of Kluyveromyces marxianus M3 isolated from Tibetan mushrooms on diet-induced hypercholesterolemia in rat.

    PubMed

    Xie, Yuanhong; Zhang, Hongxing; Liu, Hui; Xiong, Lixia; Gao, Xiuzhi; Jia, Hui; Lian, Zhengxing; Tong, Nengsheng; Han, Tao

    2015-06-01

    To investigate the effects of Kluyveromyces marxianus M3 isolated from Tibetan mushrooms on diet-induced hypercholesterolemia in rats, female Wistar rats were fed a high-cholesterol diet (HCD) for 28 d to generate hyperlipidemic models. Hyperlipidemic rats were assigned to four groups, which were individually treated with three different dosages of K. marxianus M3+HCD or physiological saline+HCD via oral gavage for 28 d. The total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) levels in the serum and liver of the rats were measured using commercially available enzyme kits. In addition, the liver morphology was also examined using hematoxylin and eosin staining and optical microscopy. According to our results, the serum and liver TC, TG, LDL-C levels and atherogenic index (AI) were significantly decreased in rats orally administered K. marxianus M3 (p <0.01), and the HDL-C levels and anti atherogenic index (AAI) were significantly increased (p <0.01) compared to the control group. Moreover, K. marxianus M3 treatment also reduced the build-up of lipid droplets in the liver and exhibited normal hepatocytes, suggesting a protective effect of K. marxianus M3 in hyperlipidemic rats.

  5. Genetic environments of the transferable plasmid-mediated blaCTX-M-3 gene in Serratia marcescens isolates.

    PubMed

    Chu, Pei-Yu; Peng, Chien-Fang

    2014-01-01

    In this study, genetic environments of the transferable plasmid-mediated blaCTX-M-3 gene were characterized among 14 isolates of cefotaxime-resistant Serratia marcescens using PCR and BLAST DNA sequence analysis. A total of 3 types of genetic architectures in the regions surrounding this blaCTX-M-3 gene were identified. Type I architecture was characterized by the presence of a complete insertion sequence of tnpA-ISEcp1, identified as interrupting a reverse IS26 sequence in the upstream region of the blaCTX-M-3 gene. A reverse-directional orf477 fragment was located downstream of the blaCTX-M-3 gene, which was in the same direction of the mucA gene. A common region containing the orf513 element was located upstream of the mucA gene. Moreover, a copy of the 3'-CS2 element was located immediately upstream of the orf513 element. A novel complex class 1 integron was characterized by the presence of the dfrA19 gene, which was flanked by two copies of class 1 integrons. This is the first report to describe the dfrA19 gene within a novel complex class 1 integron in S. marcescens isolates from Taiwan. This novel complex class 1 integron structure was located distantly upstream of the blaCTX-M-3 gene.

  6. Hypocholesterolemic effects of Kluyveromyces marxianus M3 isolated from Tibetan mushrooms on diet-induced hypercholesterolemia in rat

    PubMed Central

    Xie, Yuanhong; Zhang, Hongxing; Liu, Hui; Xiong, Lixia; Gao, Xiuzhi; Jia, Hui; Lian, Zhengxing; Tong, Nengsheng; Han, Tao

    2015-01-01

    To investigate the effects of Kluyveromyces marxianus M3 isolated from Tibetan mushrooms on diet-induced hypercholesterolemia in rats, female Wistar rats were fed a high-cholesterol diet (HCD) for 28 d to generate hyperlipidemic models. Hyperlipidemic rats were assigned to four groups, which were individually treated with three different dosages of K. marxianus M3+HCD or physiological saline+HCD via oral gavage for 28 d. The total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) levels in the serum and liver of the rats were measured using commercially available enzyme kits. In addition, the liver morphology was also examined using hematoxylin and eosin staining and optical microscopy. According to our results, the serum and liver TC, TG, LDL-C levels and atherogenic index (AI) were significantly decreased in rats orally administered K. marxianus M3 (p <0.01), and the HDL-C levels and anti atherogenic index (AAI) were significantly increased (p <0.01) compared to the control group. Moreover, K. marxianus M3 treatment also reduced the build-up of lipid droplets in the liver and exhibited normal hepatocytes, suggesting a protective effect of K. marxianus M3 in hyperlipidemic rats. PMID:26273253

  7. Real-time monitoring of genetically modified Chlamydomonas reinhardtii during the Foton M3 space mission and ground irradiation experiment

    NASA Astrophysics Data System (ADS)

    Lambreva, Maya; Rea, Giuseppina; Antonacci, Amina; Serafini, Agnese; Damasso, Mario; Margonelli, Andrea; Johanningmeier, Udo; Bertalan, Ivo; Pezzotti, Gianni; Giardi, Maria Teresa

    Long-term space exploration, colonization or habitation requires biological life support systems capable to cope with the deleterious space environment. The use of oxygenic photosynthetic microrganisms is an intriguing possibility mainly for food, O2 and nutraceutical compounds production. The critical points of utilizing plantsor algae-based life support systems are the microgravity and the ionizing radiation, which can influence the performance of these organisms. The aim of the present study was to assess the effects of space environment on the photosynthetic activity of various microrganisms and to select space stress-tolerant strains. Site-directed and random mutants of the unicellular green alga Chlamydomonas reinhardtii of Photosystem II D1 protein were used as a model system to test and select the amino acid substitutions capable to account for space stress tolerance. We focussed our studies also on the accumulation of the Photosystem II photoprotective carotenoids (the xantophylls violaxanthin, anteraxanthin and zeaxanthin), powerful antioxidants that epidemiological studies demonstrated to be human vision protectors. Metabolite profiling by quantitative HPLC methods revealed the organisms and the stress conditions capable to accumulate the highest pigment levels. In order to develop a project for a rationale metabolic engineering of algal secondary metabolites overproduction, we are performing expression analyses on the carotenoid biosynthetic pathway under physiological and mimicked space conditions. To identify the consequences of the space environment on the photosynthetic apparatus the changes in the Photosystem II efficiency were monitored in real time during the ESA-Russian Foton-M3 mission in September 2007. For the space flight a high-tech, multicell fluorescence biosensor, Photo-II, was designed and built by the Centre for Advanced Research in Space Optics in collaboration with Kayser-Italy, Biosensor and DAS. Photo-II is an automatic device

  8. Missing energies at pair creation

    NASA Technical Reports Server (NTRS)

    El-Ela, A. A.; Hassan, S.; Bagge, E. R.

    1985-01-01

    Wilson cloud chamber measurements of the separated spectra of positrons and electrons produced by gamma quanta of 6.14 MeV differ considerably from the theoretically predicted spectra by BETHE and HEITLER, but are in good agreement with those of a modified theory of pair creation.

  9. Cooper pair transfer in nuclei

    NASA Astrophysics Data System (ADS)

    Potel, G.; Idini, A.; Barranco, F.; Vigezzi, E.; Broglia, R. A.

    2013-10-01

    The second-order distorted wave Born approximation implementation of two-particle transfer direct reactions which includes simultaneous and successive transfer, properly corrected by non-orthogonality effects, is tested with the help of controlled nuclear structure and reaction inputs against data spanning the whole mass table, and showed to constitute a quantitative probe of nuclear pairing correlations.

  10. Pick a Pair. Being Bony

    ERIC Educational Resources Information Center

    Miller, Pat

    2004-01-01

    This column suggests pairings of fiction and nonfiction books to meet curricular needs and help students to compare/contrast the texts as they may be asked on state tests. The author of this paper focuses on activities surrounding Halloween. Since many schools are discouraged from teaching about Halloween, this can be a great time to investigate…

  11. Pairing Linguistic and Music Intelligences

    ERIC Educational Resources Information Center

    DiEdwardo, MaryAnn Pasda

    2005-01-01

    This article describes how music in the language classroom setting can be a catalyst for developing reading, writing, and understanding skills. Studies suggest that pairing music and linguistic intelligences in the college classroom improves students' grades and abilities to compose theses statements for research papers in courses that emphasize…

  12. Characterization of V0162, a new long-acting antagonist at human M3 muscarinic acetylcholine receptors.

    PubMed

    Heusler, Peter; Cussac, Didier; Naline, Emmanuel; Tardif, Stéphanie; Clerc, Thierry; Devillier, Philippe

    2015-10-01

    The anticholinergic properties of the mequitazine enantiomer V0162 make it a drug candidate for the treatment of chronic obstructive airway diseases. Here, we compared V0162's in vitro pharmacological activity at recombinant human M3 muscarinic acetylcholine receptors (hM3Rs) with that of other anticholinergics, using (i) a radioligand binding assay, (ii) a functional reporter gene assay and (iii) a bronchoconstriction inhibition assay on human bronchial preparations. V0162 had high affinity for hM3Rs, with a pKi varying from 9.01 after a 2 h incubation to 9.21 after 23 h. The other mequitazine enantiomer (V0114) was less potent. V0162 displayed rapid off-kinetics and a biphasic time course of binding. V0162 was found to be an antagonist behaving as an inverse agonist for hM3R-mediated reporter gene activation, with much the same efficacy as atropine, ipratropium and tiotropium. However, in contrast to ipratropium and atropine, V0162's inhibitory potency was only slightly affected by compound washout. V0162 antagonized acetylcholine-mediated contractions in a human bronchial preparation; the pA2 values increased with the incubation time (up to 2 h). Moreover, there was a progressive increase in V0162's ability to inhibit electrically-induced contractions, which persisted after compound washout. In conclusion, V0162 is the most active mequitazine enantiomer at hM3Rs and shows a complex pattern of binding to the membrane compartment. These particular features may be of therapeutic value when persistent antagonism at hM3Rs is required. PMID:26241178

  13. Characterization of V0162, a new long-acting antagonist at human M3 muscarinic acetylcholine receptors.

    PubMed

    Heusler, Peter; Cussac, Didier; Naline, Emmanuel; Tardif, Stéphanie; Clerc, Thierry; Devillier, Philippe

    2015-10-01

    The anticholinergic properties of the mequitazine enantiomer V0162 make it a drug candidate for the treatment of chronic obstructive airway diseases. Here, we compared V0162's in vitro pharmacological activity at recombinant human M3 muscarinic acetylcholine receptors (hM3Rs) with that of other anticholinergics, using (i) a radioligand binding assay, (ii) a functional reporter gene assay and (iii) a bronchoconstriction inhibition assay on human bronchial preparations. V0162 had high affinity for hM3Rs, with a pKi varying from 9.01 after a 2 h incubation to 9.21 after 23 h. The other mequitazine enantiomer (V0114) was less potent. V0162 displayed rapid off-kinetics and a biphasic time course of binding. V0162 was found to be an antagonist behaving as an inverse agonist for hM3R-mediated reporter gene activation, with much the same efficacy as atropine, ipratropium and tiotropium. However, in contrast to ipratropium and atropine, V0162's inhibitory potency was only slightly affected by compound washout. V0162 antagonized acetylcholine-mediated contractions in a human bronchial preparation; the pA2 values increased with the incubation time (up to 2 h). Moreover, there was a progressive increase in V0162's ability to inhibit electrically-induced contractions, which persisted after compound washout. In conclusion, V0162 is the most active mequitazine enantiomer at hM3Rs and shows a complex pattern of binding to the membrane compartment. These particular features may be of therapeutic value when persistent antagonism at hM3Rs is required.

  14. Mineralogy of the Lunar Crust in Spatial Context: First Results from the Moon Mineralogy Mapper (M3)

    NASA Technical Reports Server (NTRS)

    Pieters, C. M.; Boardman, J.; Buratti, B.; Clark, R.; Combe, J-P; Green, R.; Goswami, J. N.; Head, J. W., III; Hicks, M.; Isaacson, P.; Klima, R.; Kramer, G.; Kumar, S.; Lundeen, S.; Malaret, E.; McCord, T. B.; Mustard, J.; Nettles, J.; Petro, N.; Runyon, C.; Staid, M. I.; Sunshine, J.; Taylor, L.; Tompkins, S.; Varanasi, P.

    2009-01-01

    India's Chandrayaan-1 successfully launched October 22, 2008 and went into lunar orbit a few weeks later. Commissioning of instruments began in late November and was near complete by the end of the year. Initial data for NASA's Moon Mineralogy Mapper (M3) were acquired across the Orientale Basin and the science results are discussed here. M 3 image-cube data provide mineralogy of the surface in geologic context. A major new result is that the existence and distribution of massive amounts of anorthosite as a continuous stratigraphic crustal layer is now irrefutable.

  15. Observation of M3 isomeric transition from 156mPm through the βdecay of 156Nd

    NASA Astrophysics Data System (ADS)

    Shibata, M.; Suematsu, O.; Kojima, Y.; Kawade, K.; Taniguchi, A.; Kawase, Y.

    2007-02-01

    An M3 transition in a doubly odd nucleus of 156Pm was identified by internal conversion electron measurement through the β-decay of 156Nd which was separated from the fission products of 235U using the on-line mass separator KUR-ISOL. The isomeric state at 150.3keV de-excites to the ground state with the M3 transition, and the spin-parity is considered to be 1-. Nilsson configurations are also discussed on the basis of the systematics.

  16. Observing RR Lyrae Variables in the M3 Globular Cluster with the BYU West Mountain Observatory (Abstract)

    NASA Astrophysics Data System (ADS)

    Joner, M. D.

    2016-06-01

    (Abstract only) We have utilized the 0.9-meter telescope of the Brigham Young University West Mountain Observatory to secure data on the northern hemisphere globular cluster NGC 5272 (M3). We made 216 observations in the V filter spaced between March and August 2012. We present light curves of the M3 RR Lyrae stars using different techniques. We compare light curves produced using DAOPHOT and ISIS software packages for stars in both the halo and core regions of this globular cluster. The light curve fitting is done using FITLC.

  17. Electrostatic ion waves in non-Maxwellian pair-ion plasmas

    SciTech Connect

    Arshad, Kashif; Mahmood, S.

    2010-12-15

    The electrostatic ion waves are studied for non-Maxwellian or Lorentzian distributed unmagnetized pair-ion plasmas. The Vlasov equation is solved and damping rates are calculated for electrostatic waves in Lorentzian pair-ion plasmas. The damping rates of the electrostatic ion waves are studied for the equal and different ion temperatures of pair-ion species. It is found that the Landau damping rate of the ion plasma wave is increased in Lorentzian plasmas in comparison with Maxwellian pair-ion plasmas. The numerical results are also presented for illustration by taking into account the parameters reported in fullerene pair-ion plasma experiments.

  18. Pairing state with a time-reversal symmetry breaking in FeAs-based superconductors.

    PubMed

    Lee, Wei-Cheng; Zhang, Shou-Cheng; Wu, Congjun

    2009-05-29

    We investigate the competition between the extended s+/--wave and dx2-y2-wave pairing order parameters in the iron-based superconductors. Because of the frustrating pairing interactions among the electron and the hole Fermi pockets, a time-reversal symmetry breaking s+id pairing state could be favored. We analyze this pairing state within the Ginzburg-Landau theory and explore the experimental consequences. In such a state, spatial inhomogeneity induces a supercurrent near a nonmagnetic impurity and the corners of a square sample. The resonance mode between the s+/-- and dx2-y2-wave order parameters can be detected through the B1g Raman spectroscopy.

  19. Pairing state with a time-reversal symmetry breaking in FeAs-based superconductors

    SciTech Connect

    Lee, Wei-Sheng

    2010-05-26

    We investigate the competition between the extended s{+-} wave and dx2-y2 -wave pairing order parameters in the iron-based superconductors. Because of the frustrating pairing interactions among the electron and the hole fermi pockets, a time-reversal symmetry breaking s + id pairing state could be favored. We analyze this pairing state within the Ginzburg-Landau theory, and explore the experimental consequences. In such a state, spatial inhomogeneity induces supercurrent near a non-magnetic impurity and the corners of a square sample. The resonance mode between the s{+-} and dx2?y2 -wave order parameters can be detected through the B1g-Raman spectroscopy.

  20. 1450 m^3 at 10^-9 Pa: One of the KATRIN Challenges

    SciTech Connect

    Christian Day; R. Gumbsheimer; W. Herz; J. Wolf; J. Bonn; R. Reid; G.R. Myneni

    2006-11-12

    The KATRIN project is a challenging experiment to measure the mass of the electron neutrino directly with a sensitivity of 0.2 eV. It is a next generation tritium beta-decay experiment scaling up the size and precision of previous experiments by an order of magnitude as well as the intensity of the tritium beta source. Ultrafine spectrometric analysis of the energy distribution of the decay electrons at their very endpoint of 18.57 keV is the key to derive the neutrino mass. This is provided by a high-resolution spectrometer of unique size (10 m in diameter, 22 m in length). To avoid any negative influence from residual gas, the spectrometer vessel is designed to UHV/XHV conditions (an ultimate total pressure of below 10{sup -9} Pa and a wall outgassing rate below 10{sup -13} Pam{sup 3}/scm{sup 2}). The paper shortly describes the experimental idea behind KATRIN. The emphasis will then be given to the pumping concept for how to achieve the target parameters and to the manufacturing of the spectrometer tank. Critical issues will also be discussed (surface treatment, welding, transportation). Finally, a description of the current status and an outlook on the overall KATRIN schedule completes the paper.

  1. The horizontal branch in the UV colour-magnitude diagrams - II. The case of M3, M13 and M79

    NASA Astrophysics Data System (ADS)

    Dalessandro, E.; Salaris, M.; Ferraro, F. R.; Mucciarelli, A.; Cassisi, S.

    2013-03-01

    We present a detailed comparison between far-ultraviolet (UV)/optical colour-magnitude diagrams obtained with high-resolution Hubble Space Telescope data and suitable theoretical models for three Galactic globular clusters: M3, M13 and M79. These systems represents a `classical' example of clusters in the intermediate-metallicity regime that, even sharing similar metal content and age, show remarkably different horizontal branch morphologies. As a consequence, the observed differences in the colour distributions of horizontal branch stars cannot be interpreted in terms of either first (metallicity) or a second parameter such as age. We investigate here the possible role of variations of initial helium abundance (Y). Thanks to the use of a proper setup of far-UV filters, we are able to put strong constraints on the maximum Y (Ymax) values compatible with the data. We find differences Δ Y_max˜ 0.02-0.04 between the clusters with M13 showing the largest value (Ymax ˜ 0.30) and M3 the smallest (Ymax ˜ 0.27). In general, we observe that these values are correlated with the colour extensions of their horizontal branches and with the range of the observed NaO anticorrelations.

  2. Reactor Dosimetry Applications Using RAPTOR-M3G:. a New Parallel 3-D Radiation Transport Code

    NASA Astrophysics Data System (ADS)

    Longoni, Gianluca; Anderson, Stanwood L.

    2009-08-01

    The numerical solution of the Linearized Boltzmann Equation (LBE) via the Discrete Ordinates method (SN) requires extensive computational resources for large 3-D neutron and gamma transport applications due to the concurrent discretization of the angular, spatial, and energy domains. This paper will discuss the development RAPTOR-M3G (RApid Parallel Transport Of Radiation - Multiple 3D Geometries), a new 3-D parallel radiation transport code, and its application to the calculation of ex-vessel neutron dosimetry responses in the cavity of a commercial 2-loop Pressurized Water Reactor (PWR). RAPTOR-M3G is based domain decomposition algorithms, where the spatial and angular domains are allocated and processed on multi-processor computer architectures. As compared to traditional single-processor applications, this approach reduces the computational load as well as the memory requirement per processor, yielding an efficient solution methodology for large 3-D problems. Measured neutron dosimetry responses in the reactor cavity air gap will be compared to the RAPTOR-M3G predictions. This paper is organized as follows: Section 1 discusses the RAPTOR-M3G methodology; Section 2 describes the 2-loop PWR model and the numerical results obtained. Section 3 addresses the parallel performance of the code, and Section 4 concludes this paper with final remarks and future work.

  3. Application of Paired-Comparison Methods to Hearing Aids

    PubMed Central

    Amlani, Amyn M.; Schafer, Erin C.

    2009-01-01

    The method of paired comparisons was introduced into the hearing aid literature nearly 50 years ago. Over time, studies have found paired comparisons to be sensitive, valid, and reliable in determining either the perceptual difference or relative ranking among hearing aids and electroacoustic characteristics. With the increasing number of adjustable electroacoustic parameters in today's digital hearing aids—and the lack of procedural guidelines necessary to fit many of them—the method of paired comparisons provides the clinician with the ability to compare different devices, electroacoustic characteristics, memory settings, or combinations of these variables under the listener's everyday listening conditions. Furthermore, this procedure provides the clinician with the ability to individualize the prescriptive approach—which is predicated mainly on hearing threshold data and listening in quiet—so that a combination of parameters can be set to optimize the user's listening needs in a given environment. In this article, the authors present an overview of the theoretical principle supporting this procedure, the various paired-comparison strategies and associated approaches, the advantages of this method, and recommended procedures for implementing the method of paired comparisons in the fitting of today's sophisticated hearing aids. PMID:20150188

  4. Pair production in inhomogeneous fields

    SciTech Connect

    Gies, Holger; Klingmueller, Klaus

    2005-09-15

    We employ the recently developed worldline numerics, which combines string-inspired field theory methods with Monte Carlo techniques, to develop an algorithm for the computation of pair-production rates in scalar QED for inhomogeneous background fields. We test the algorithm with the classic Sauter potential, for which we compute the local production rate for the first time. Furthermore, we study the production rate for a superposition of a constant E field and a spatially oscillating field for various oscillation frequencies. Our results reveal that the approximation by a local derivative expansion already fails for frequencies small compared to the electron-mass scale, whereas for strongly oscillating fields a derivative expansion for the averaged field represents an acceptable approximation. The worldline picture makes the nonlocal nature of pair production transparent and facilitates a profound understanding of this important quantum phenomenon.

  5. Flux Quantization Without Cooper Pairs

    NASA Astrophysics Data System (ADS)

    Kadin, Alan

    2013-03-01

    It is universally accepted that the superconducting flux quantum h/2e requires the existence of a phase-coherent macroscopic wave function of Cooper pairs, each with charge 2e. On the contrary, we assert that flux quantization can be better understood in terms of single-electron quantum states, localized on the scale of the coherence length and organized into a real-space phase-antiphase structure. This packing configuration is consistent with the Pauli exclusion principle for single-electron states, maintains long-range phase coherence, and is compatible with much of the BCS formalism. This also accounts for h/2e in the Josephson effect, without Cooper pairs. Experimental evidence for this alternative picture may be found in deviations from h/2e in loops and devices much smaller than the coherence length. A similar phase-antiphase structure may also account for superfluids, without the need for boson condensation.

  6. One-dimensional Cooper pairing

    NASA Astrophysics Data System (ADS)

    Mendoza, R.; Fortes, M.; de Llano, M.; Solís, M. A.

    2011-09-01

    We study electron pairing in a one-dimensional (1D) fermion gas at zero temperature under zero- and finite-range, attractive, two-body interactions. The binding energy of Cooper pairs (CPs) with zero total or center-of-mass momentum (CMM) increases with attraction strength and decreases with interaction range for fixed strength. The excitation energy of 1D CPs with nonzero CMM display novel, unique properties. It satisfies a dispersion relation with two branches: a phonon-like linear excitation for small CP CMM; this is followed by roton-like quadratic excitation minimum for CMM greater than twice the Fermi wavenumber, but only above a minimum threshold attraction strength. The expected quadratic-in-CMM dispersion in vacuo when the Fermi wavenumber is set to zero is recovered for any coupling. This paper completes a three-part exploration initiated in 2D and continued in 3D.

  7. Lead generation using pharmacophore mapping and three-dimensional database searching: application to muscarinic M(3) receptor antagonists.

    PubMed

    Marriott, D P; Dougall, I G; Meghani, P; Liu, Y J; Flower, D R

    1999-08-26

    By using a pharmacophore model, a geometrical representation of the features necessary for molecules to show a particular biological activity, it is possible to search databases containing the 3D structures of molecules and identify novel compounds which may possess this activity. We describe our experiences of establishing a working 3D database system and its use in rational drug design. By using muscarinic M(3) receptor antagonists as an example, we show that it is possible to identify potent novel lead compounds using this approach. Pharmacophore generation based on the structures of known M(3) receptor antagonists, 3D database searching, and medium-throughput screening were used to identify candidate compounds. Three compounds were chosen to define the pharmacophore: a lung-selective M(3) antagonist patented by Pfizer and two Astra compounds which show affinity at the M(3) receptor. From these, a pharmacophore model was generated, using the program DISCO, and this was used subsequently to search a UNITY 3D database of proprietary compounds; 172 compounds were found to fit the pharmacophore. These compounds were then screened, and 1-[2-(2-(diethylamino)ethoxy)phenyl]-2-phenylethanone (pA(2) 6.67) was identified as the best hit, with N-[2-(piperidin-1-ylmethyl)cycohexyl]-2-propoxybenz amide (pA(2) 4. 83) and phenylcarbamic acid 2-(morpholin-4-ylmethyl)cyclohexyl ester (pA(2) 5.54) demonstrating lower activity. As well as its potency, 1-[2-(2-(diethylamino)ethoxy)phenyl]-2-phenylethanone is a simple structure with limited similarity to existing M(3) receptor antagonists.

  8. Segmentation and the pairing hypothesis.

    PubMed

    Bragason, Orn

    2004-09-30

    The effect of stimulus contiguity and response contingency on responding in chain schedules was examined in two experiments. In Experiment 1, four pigeons were trained on two simple three-link chain schedules that alternated within sessions. Initial links were correlated with a variable-interval 30s schedule, and middle and terminal links were correlated with interdependent variable-interval 30s variable-interval 30s schedules. The combined duration of the interdependent schedules summed to 60s. The two chains differed with respect to signaling of the schedule components: a two-stimulus chain had one stimulus paired with the initial link and one stimulus paired with both the middle and the terminal link, while a three-stimulus chain had a different stimulus paired with the each of the three links. The results showed that the two-stimulus chain maintained lower initial-link responding than the three-stimulus chain. In Experiment 2, four pigeons were exposed to three separate conditions, the two- and three-stimulus chains of Experiment 1 and a three-stimulus chain that had a 3s delay to terminal-link entry from the middle-link response that produced it. The two-stimulus chain maintained lower initial-link responding than the three-stimulus chain, as in Experiment 1, and a similar initial-link responding was maintained by the two-stimulus chain and the three-stimulus chain with the delay contingency. The results demonstrate that a stimulus noncontiguous with food can maintain responding that is sometimes greater than a stimulus contiguous with food, depending on the response contingency for terminal-link entry. The results are contrary to the pairing hypothesis of conditioned reinforcement.

  9. Asymmetric Ion-Pairing Catalysis

    PubMed Central

    Brak, Katrien

    2014-01-01

    Charged intermediates and reagents are ubiquitous in organic transformations. The interaction of these ionic species with chiral neutral, anionic, or cationic small molecules has emerged as a powerful strategy for catalytic, enantioselective synthesis. This review describes developments in the burgeoning field of asymmetric ion-pairing catalysis with an emphasis on the insights that have been gleaned into the structural and mechanistic features that contribute to high asymmetric induction. PMID:23192886

  10. Floquet theory of radical pairs in radiofrequency magnetic fields

    NASA Astrophysics Data System (ADS)

    Hiscock, Hamish G.; Kattnig, Daniel R.; Manolopoulos, David E.; Hore, P. J.

    2016-09-01

    We present a new method for calculating the product yield of a radical pair recombination reaction in the presence of a weak time-dependent magnetic field. This method successfully circumvents the computational difficulties presented by a direct solution of the Liouville-von Neumann equation for a long-lived radical pair containing many hyperfine-coupled nuclear spins. Using a modified formulation of Floquet theory, treating the time-dependent magnetic field as a perturbation, and exploiting the slow radical pair recombination, we show that one can obtain a good approximation to the product yield by considering only nearly degenerate sub-spaces of the Floquet space. Within a significant parameter range, the resulting method is found to give product yields in good agreement with exact quantum mechanical results for a variety of simple model radical pairs. Moreover it is considerably more efficient than the exact calculation, and it can be applied to radical pairs containing significantly more nuclear spins. This promises to open the door to realistic theoretical investigations of the effect of radiofrequency electromagnetic radiation on the photochemically induced radical pair recombination reactions in the avian retina which are believed to be responsible for the magnetic compass sense of migratory birds.

  11. Conveniently assembled multiple-electrode-pair CO2 laser

    NASA Astrophysics Data System (ADS)

    Ye, Lihua; Li, Xiangyen; He, Anzhi

    2000-04-01

    A conveniently assembled multiple-electrode-pair (MEP) transversely excited amplify (TEA) CO2 laser is introduced in this paper. The laser is described from the view of device configuration, power supply, control circuit, and etc. The laser output is variable from single pulse to double pulse and multiple pulse with different assembly. We adopt a new alignment method for cavity. The pulse time interval given by control system is continuously adjustable from 0 to 150 microseconds. Experiments prove that the pulse series property is stable and that the pulse parameters are perfect. The conveniently assembled laser lay a foundation for the industry application of multiple-electrode-pair CO2 laser.

  12. Isospin-dependent pairing interaction from nuclear matter calculations

    SciTech Connect

    Zhang, S. S.; Cao, L. G.; Lombardo, U.; Zhao, E. G.; Zhou, S. G.

    2010-04-15

    The isospin dependence of the effective pairing interaction is discussed on the basis of the Bardeen, Cooper, and Schrieffer theory of superfluid asymmetric nuclear matter. It is shown that the energy gap, calculated within the mean field approximation in the range from symmetric nuclear matter to pure neutron matter, is not linearly dependent on the symmetry parameter owing to the nonlinear structure of the gap equation. Moreover, the construction of a zero-range effective pairing interaction compatible with the neutron and proton gaps in homogeneous matter is investigated, along with some recent proposals of isospin dependence tested on the nuclear data table.

  13. Coupling of the pairing vibrations with the fission mode

    NASA Astrophysics Data System (ADS)

    Staszczak, A.; Baran, A.; Pomorski, K.; Böning, K.

    1985-10-01

    The influence of collective pairing vibrations on the spontaneous fission lifetimes are studied. The Nilsson single-particle potential plus the monopole pairing residual interaction are used. The collective hamiltonian is obtained within the cranking model. The fission lifetimes are evaluated in the WKB approximation along the least-action trajectory in the three-dimensional space (ε 24, Δ p, Δ n) . When taking into account the mean paring-field parameters (Δ p, Δ n) as dynamical variables, the theoretical fission lifetimes decrease by a few orders of magnitude.

  14. Passive estimation of the waveguide invariant per pair of modes.

    PubMed

    Le Gall, Yann; Bonnel, Julien

    2013-08-01

    In many oceanic waveguides, acoustic propagation is characterized by a parameter called waveguide invariant. This property is used in many passive and active sonar applications where knowledge of the waveguide invariant value is required. The waveguide invariant is classically considered as scalar but several studies show that it is better modeled by a distribution because of its dependence on frequency and mode pairs. This paper presents a new method for estimating the waveguide invariant distribution. Using the noise radiated by a distant ship and a single hydrophone, the proposed methodology allows estimating the waveguide invariant for each pair of modes in shallow water. Performance is evaluated on simulated data.

  15. Pairing phase transition and thermodynamical quantities in 148,149Sm

    NASA Astrophysics Data System (ADS)

    Razavi, R.; Behkami, A. N.; Dehghani, V.

    2014-10-01

    The nuclear level densities and entropies in 148,149Sm have been calculated in the framework of the superconducting theory that includes modified nuclear pairing gap. For modified pairing gap parameter the smooth transition from the BCS to the Fermi type distributions is used. By applying modified pairing gap, the extracted S-shaped heat capacity as a function of nuclear temperature exhibits a physical and smoother behavior instead of the singular behavior predicted by the BCS equations at critical temperature.

  16. A synthetic snRNA m3G-CAP enhances nuclear delivery of exogenous proteins and nucleic acids.

    PubMed

    Moreno, Pedro M D; Wenska, Malgorzata; Lundin, Karin E; Wrange, Orjan; Strömberg, Roger; Smith, C I Edvard

    2009-04-01

    Accessing the nucleus through the surrounding membrane poses one of the major obstacles for therapeutic molecules large enough to be excluded due to nuclear pore size limits. In some therapeutic applications the large size of some nucleic acids, like plasmid DNA, hampers their access to the nuclear compartment. However, also for small oligonucleotides, achieving higher nuclear concentrations could be of great benefit. We report on the synthesis and possible applications of a natural RNA 5'-end nuclear localization signal composed of a 2,2,7-trimethylguanosine cap (m(3)G-CAP). The cap is found in the small nuclear RNAs that are constitutive part of the small nuclear ribonucleoprotein complexes involved in nuclear splicing. We demonstrate the use of the m(3)G signal as an adaptor that can be attached to different oligonucleotides, thereby conferring nuclear targeting capabilities with capacity to transport large-size cargo molecules. The synthetic capping of oligos interfering with splicing may have immediate clinical applications.

  17. Pair Tunneling through Single Molecules

    NASA Astrophysics Data System (ADS)

    Raikh, Mikhail

    2007-03-01

    Coupling to molecular vibrations induces a polaronic shift, and can lead to a negative charging energy, U. For negative U, the occupation of the ground state of the molecule is even. In this situation, virtual pair transitions between the molecule and the leads can dominate electron transport. At low temperature, T, these transitions give rise to the charge-Kondo effect [1]. We developed the electron transport theory through the negative-U molecule [2] at relatively high T, when the Kondo correlations are suppressed. Two physical ingredients distinguish our theory from the transport through a superconducting grain coupled to the normal leads [3]: (i) in parallel with sequential pair-tunneling processes, single-particle cotunneling processes take place; (ii) the electron pair on the molecule can be created (or annihilated) by two electrons tunneling in from (or out to) opposite leads. We found that, even within the rate-equation description, the behavior of differential conductance through the negative-U molecule as function of the gate voltage is quite peculiar: the height of the peak near the degeneracy point is independent of temperature, while its width is proportional to T. This is in contrast to the ordinary Coulomb-blockade conductance peak, whose integral strength is T-independent. At finite source-drain bias, V>>T, the width of the conductance peak is ˜V, whereas the conventional Coulomb-blockade peak at finite V splits into two sharp peaks at detunings V/2, and -V/2. Possible applications to the gate-controlled current rectification and switching will be discussed. [1] A. Taraphder and P. Coleman, Phys. Rev. Lett. 66, 2814 (1991). [2] J. Koch, M. E. Raikh, and F. von Oppen, Phys. Rev. Lett. 96, 056803 (2006). [3] F. W. J. Hekking, L. I. Glazman, K. A. Matveev, and R. I. Shekhter, Phys. Rev. Lett. 70, 4138 (1993).

  18. Electrochemical properties of mixed conducting (La,M)(CoFe) oxide perovskites (M=3DSr, Ca, and Ba)

    SciTech Connect

    Stevenson, J.W.; Armstrong, T.R.; Bates, J.L.

    1996-04-01

    Electrical properties and oxygen permeation properties of solid mixed-conducting electrolytes (La,M)(CoFe) oxide perovskites (M=3DSr, Ca, and Ba) have been characterized. These materials are potentially useful as passive membranes to separate high purity oxygen from air and as the cathode in a fuel cell. Dilatometric linear expansion measurements were performed as a function of temperature and oxygen partial pressure to evaluate the stability.

  19. Meeting Report: "Metagenomics, Metadata and Meta-analysis" (M3) Workshop at the Pacific Symposium on Biocomputing 2010.

    PubMed

    Hirschman, Lynette; Sterk, Peter; Field, Dawn; Wooley, John; Cochrane, Guy; Gilbert, Jack; Kolker, Eugene; Kyrpides, Nikos; Meyer, Folker; Mizrachi, Ilene; Nakamura, Yasukazu; Sansone, Susanna-Assunta; Schriml, Lynn; Tatusova, Tatiana; White, Owen; Yilmaz, Pelin

    2010-06-15

    This report summarizes the M3 Workshop held at the January 2010 Pacific Symposium on Biocomputing. The workshop, organized by Genomic Standards Consortium members, included five contributed talks, a series of short presentations from stakeholders in the genomics standards community, a poster session, and, in the evening, an open discussion session to review current projects and examine future directions for the GSC and its stakeholders.

  20. Biphasic MO2+x-M3O8-z domain of the U-Pu-O phase diagram.

    PubMed

    Strach, Michal; Belin, Renaud C; Richaud, Jean-Christophe; Rogez, Jacques

    2015-09-21

    The reduction of six mixed-oxide samples containing 14, 24, 35, 46, 54, and 62 mol % Pu was studied in situ by X-ray diffraction. The samples were first oxidized in air and subsequently reduced in a controlled atmosphere corresponding to a stoichiometric composition with an O/M = 2.00. After oxidation, we observed two structures, one cubic and one orthorhombic, MO2+x and M3O8-z. The two phases were subsequently reduced back to their stoichiometric O/M = 2.00 in a controlled atmosphere. The plutonium contents of the two resulting cubic structures differed from the initial one. We conclude that strong cation transport took place during oxidation, according to the shape of the tie lines in the biphasic MO2+x/M4O9-M3O8-z domain. The resulting overall O/M after oxidation was estimated. We propose the shape of the tie lines in the aforementioned biphasic domain and suggest a maximal plutonium solubility in the M3O8 structure at 8 ± 2 mol % (Pu/U + Pu) at 1573 K. PMID:26360606

  1. Pair Cascades in Blazars and Radio Galaxies

    NASA Astrophysics Data System (ADS)

    Roustazadeh Sheikhyousefi, Parisa

    2012-05-01

    magnetic field in the AGN environment, secondary particles produced by gamma-gamma absorption can be isotropized. I suggested that the Compton emission from VHE gamma-ray induced pair cascades can explain the detection of radio galaxies as high energy sources. I presented fits to the the Fermi fluxes and spectra of the radio galaxies Cen A and NGC 1275. In the last part of my Ph. D. research work, I developed my Monte-Carlo code to include energy loss of particles by synchrotron radiation between to successive Compton scatterings and the angle dependence of the synchrotron output from the cascade. This can be important for situations when the magnetic field in the AGN environment is not negligible. I showed that the synchrotron radiation from the cascades in the radio galaxies NGC 1275 and Cen A with the parameters used in my first and second paper are much smaller than the synchrotron radiation from the jets and neglecting synchrotron radiation in those works is justified. I found that the magnetic field can not be determined from a fit of the cascade emission to the gamma-ray spectrum alone. I studied this scenario for the case of NGC 1275 and showed that the degeneracy of the magnetic field can only be lifted if the synchrotron emission from the cascade is observed as well. I suggest that the big blue bump (BBB) observed in the spectral energy distribution (SED) of several blazars can be due to the synchrotron radiation from cascades. This can be an alternative explanation of the BBB signature and I illustrate this idea on the blazar 3C 279. I have investigated the apparent absorption feature observed in the SEDs of some blazars such as W Comae and S5 0716+714 in the 10-100 GeV energy range and point out that this can be due to gamma-gamma absorption of primary gamma-ray photons by soft photons from the BLR or dust torus. During this study, I participated in three observing runs at the MDM observatory on Kitt Peak near Tucson, Arizona and I monitored the optical

  2. Topological superconductivity and unconventional pairing in oxide interfaces.

    PubMed

    Scheurer, Mathias S; Schmalian, Jörg

    2015-01-28

    Pinpointing the microscopic mechanism for superconductivity has proven to be one of the most outstanding challenges in the physics of correlated quantum matter. Thus far, the most direct evidence for an electronic pairing mechanism is the observation of a new symmetry of the order parameter, as done in the cuprate high-temperature superconductors. Alternatively, global, topological invariants allow for a sharp discrimination between states of matter that cannot be transformed into each other adiabatically. Here we propose an unconventional pairing state for the electron fluid in two-dimensional oxide interfaces and establish a direct link to the emergence of non-trivial topological invariants. Topological signatures, in particular Majorana edge states, can then be used to detect the microscopic origin of superconductivity. In addition, we show that also the density wave states that compete with superconductivity sensitively depend on the nature of the pairing interaction.

  3. Topological superconductivity and unconventional pairing in oxide interfaces.

    PubMed

    Scheurer, Mathias S; Schmalian, Jörg

    2015-01-01

    Pinpointing the microscopic mechanism for superconductivity has proven to be one of the most outstanding challenges in the physics of correlated quantum matter. Thus far, the most direct evidence for an electronic pairing mechanism is the observation of a new symmetry of the order parameter, as done in the cuprate high-temperature superconductors. Alternatively, global, topological invariants allow for a sharp discrimination between states of matter that cannot be transformed into each other adiabatically. Here we propose an unconventional pairing state for the electron fluid in two-dimensional oxide interfaces and establish a direct link to the emergence of non-trivial topological invariants. Topological signatures, in particular Majorana edge states, can then be used to detect the microscopic origin of superconductivity. In addition, we show that also the density wave states that compete with superconductivity sensitively depend on the nature of the pairing interaction. PMID:25629433

  4. Kinetic pathways of ion pair dissociation in water

    SciTech Connect

    Geissler, P.L.; Dellago, C.; Chandler, D.

    1999-05-06

    The authors have successfully applied the transition path sampling method to the deterministic dynamics of a many-body system with long-ranged interactions. The process they investigate, dissociation of a model Na{sup +}Cl{sup {minus}} ion pair in water, involves a wide range of transition pathways in which collective solvent motions play an important role. Transition states along these pathways encompass a broad distribution of ionic separations. Ion pairs in contact remain associated for {approximately}20 ps on average, a time scale considerably longer than the {approximately}3ps predicted by transition state theory with ionic separation as the order parameter. In contrast to theories of barrier crossing based upon frictional effects (with or without memory), the authors find that the discrepancy between these time scales arises from neglected solvent free energy barriers rather than stochastic buffeting of the ion pair.

  5. Pairing in bulk nuclear matter beyond BCS

    SciTech Connect

    Ding, D.; Dickhoff, W. H.; Dussan, H.; Witte, S. J.; Rios, A.; Polls, A.

    2014-10-15

    The influence of short-range correlations on the spectral distribution of neutrons is incorporated in the solution of the gap equation for the {sup 3}P{sub 2}−{sup 3}F{sub 2} coupled channel in pure neutron matter. This effect is studied for different realistic interactions including one based on chiral perturbation theory. The gap in this channel vanishes at all relevant densities due to the treatment of these correlations. We also consider the effect of long-range correlations by including polarization terms in addition to the bare interaction which allow the neutrons to exchange density and spin fluctuations governed by the strength of Landau parameters allowed to have reasonable values consistent with the available literature. Preliminary results indicate that reasonable values of these parameters do not generate a gap in the {sup 3}P{sub 2}−{sup 3}F{sub 2} coupled channel either for all three realistic interactions although the pairing interaction becomes slightly more attractive.

  6. Rashba Splitting of Cooper Pairs

    NASA Astrophysics Data System (ADS)

    Shekhter, R. I.; Entin-Wohlman, O.; Jonson, M.; Aharony, A.

    2016-05-01

    We investigate theoretically the properties of a weak link between two superconducting leads, which has the form of a nonsuperconducting nanowire with a strong Rashba spin-orbit coupling caused by an electric field. In the Coulomb-blockade regime of single-electron tunneling, we find that such a weak link acts as a "spin splitter" of the spin states of Cooper pairs tunneling through the link, to an extent that depends on the direction of the electric field. We show that the Josephson current is sensitive to interference between the resulting two transmission channels, one where the spins of both members of a Cooper pair are preserved and one where they are both flipped. As a result, the current is a periodic function of the strength of the spin-orbit interaction and of the bending angle of the nanowire (when mechanically bent); an identical effect appears due to strain-induced spin-orbit coupling. In contrast, no spin-orbit induced interference effect can influence the current through a single weak link connecting two normal metals.

  7. Rashba Splitting of Cooper Pairs.

    PubMed

    Shekhter, R I; Entin-Wohlman, O; Jonson, M; Aharony, A

    2016-05-27

    We investigate theoretically the properties of a weak link between two superconducting leads, which has the form of a nonsuperconducting nanowire with a strong Rashba spin-orbit coupling caused by an electric field. In the Coulomb-blockade regime of single-electron tunneling, we find that such a weak link acts as a "spin splitter" of the spin states of Cooper pairs tunneling through the link, to an extent that depends on the direction of the electric field. We show that the Josephson current is sensitive to interference between the resulting two transmission channels, one where the spins of both members of a Cooper pair are preserved and one where they are both flipped. As a result, the current is a periodic function of the strength of the spin-orbit interaction and of the bending angle of the nanowire (when mechanically bent); an identical effect appears due to strain-induced spin-orbit coupling. In contrast, no spin-orbit induced interference effect can influence the current through a single weak link connecting two normal metals. PMID:27284669

  8. In Search of Fresh Material on Asteroid Pairs

    NASA Astrophysics Data System (ADS)

    Polishook, David; Moskovitz, N.; Binzel, R. P.; DeMeo, F.; Vokrouhlicky, D.

    2013-10-01

    Asteroid Pairs are those found to share almost identical orbital elements. Studies have shown that each pair had a single progenitor that split in the last ~1 Myrs due to rotational-fission of a ‘rubble-pile’ structured body. This process may have exposed non-weathered sub-surface material, thus examining pairs' reflectance spectra could inform us about the physics of the rotational-fission mechanism. We report near-IR spectroscopic observations of a sample of 25 asteroid pairs, performed with the IRTF and Magellan telescopes. Since the rough division of the spectral taxonomy has arbitrary borders, and in order to quantify the extent of weathering, we analyzed the features of the spectra: the slope and the center and width of the 1-micron absorption band. We compared these values to those of asteroids of the background population that were measured in the same manner and were chosen to match the range of absolute magnitude and an orbit within the main belt. While the preliminary results show that the pairs’ band parameters are distributed most similarly to those of fresh objects (Q-type) than of weathered asteroids (S-type), a careful examination reveals that asteroid pairs of the Ordinary Chondrite type may be observationally biased towards Olivine-rich asteroids (the meteoritic LL-type) that share some of the band parameters of Q-type asteroids. Since Olivine-rich asteroids are more common in the inner main belt (the Flora family) they are just easier to observe, therefore more pairs are identified within this group, even though other types of asteroids can split by rotational-fission as well. The spectral slope distributions of asteroid pairs and of the background population resemble one another with no significant distinction. This suggests that on average, there may be no readily evident for excess in fresh material that is excavated and exposed on the surfaces of asteroid pairs. This leads to a model of a gentle breakup of the fast rotating progenitor

  9. Bound Polaron Pair Formation in Poly (phenylenevinylenes)

    NASA Astrophysics Data System (ADS)

    Rothberg, Lewis

    The following sections are included: * INTRODUCTION * PHOTOGENERATED YIELD OF SINGLET EXCITONS * AGGREGRATION EFFECTS ON EXCITED STATE PHOTO-GENERATION * ASSIGNMENT TO BOUND POLARON PAIRS AND DISCUSSION * PROBLEMS WITH THE BOUND POLARON PAIR PICTURE AND CONCLUSION * REFERENCES

  10. Pair bonds: arrival synchrony in migratory birds.

    PubMed

    Gunnarsson, T G; Gill, J A; Sigurbjörnsson, T; Sutherland, W J

    2004-10-01

    Synchronous arrival of pairs of migratory birds at their breeding grounds is important for maintaining pair bonds and is achieved by pairs that remain together all year round. Here we show that arrival is also synchronized in paired individuals of a migratory shorebird, the black-tailed godwit (Limosa limosa islandica), even though they winter hundreds of kilometres apart and do not migrate together. The mechanisms required to achieve this synchrony and prevent 'divorce' illustrate the complexity of migratory systems. PMID:15470417

  11. Odd-frequency Cooper pairs in two-band superconductors and their magnetic response

    NASA Astrophysics Data System (ADS)

    Asano, Yasuhiro; Sasaki, Akihiro

    2015-12-01

    We discuss the appearance of odd-frequency Cooper pairs in two-band superconductors by solving the Gor'kov equation analytically. We introduce the equal-time s -wave pair potentials as realized in MgB2 and iron pnictides. Although the order parameter symmetry is conventional, the band degree of freedom enriches the symmetry variety of pairing correlations. The hybridization and the asymmetry between the two conduction bands induce odd-frequency pairs as a subdominant pairing correlation in the uniform ground state. To study the magnetic response of odd-frequency Cooper pairs, we analyze the Meissner kernel represented by the Gor'kov Green function. In contrast to the even-frequency pairs linked to the pair potential, the induced odd-frequency Cooper pairs indicate a paramagnetic property. We also discuss the relation between the amplitude of the odd-frequency pairing correlation and the stability of superconducting states in terms of the self-consistent equation for the pair potential.

  12. Individuation of Pairs of Objects in Infancy

    ERIC Educational Resources Information Center

    Leslie, Alan M.; Chen, Marian L.

    2007-01-01

    Looking-time studies examined whether 11-month-old infants can individuate two pairs of objects using only shape information. In order to test individuation, the object pairs were presented sequentially. Infants were familiarized either with the sequential pairs, disk-triangle/disk-triangle (XY/XY), whose shapes differed within but not across…

  13. The Associability of CVC Pairs. Research Report.

    ERIC Educational Resources Information Center

    Montague, William E.; Kiess, Harold O.

    To obtain an a priori estimate of natural language mediators (NLM's) 320 pairs of words with the consonant-vowel-consonant-pattern (CVC's) were broken into four series of 90 pairs and presented to 240 male and female undergraduates. Pairs were shown for 15 seconds while the subjects wrote down any associative device or NLM they could generate that…

  14. On the restoration of symmetry in paired Fermion systems

    SciTech Connect

    Flocard, H. |; Onishi, N.

    1997-03-01

    We consider the problem of symmetry restoration as treated by the method of variation after projection (VAP) on good quantum numbers. We show that for compact groups, the convergence of the connected-linked expansion of the VAP kernels over the physically relevant interval of integration of the pairing gauge angle is not guaranteed. We propose instead a method which generates approximations of increasing precision which are periodic with respect to the gauge angle while differing from truncations of the Fourier expansion of the VAP kernels. For the projection on good particle number in paired fermion systems, this new approach is shown to be equivalent to an expansion in powers of the pairing tensor. For the lowest order approximation, an analytical integration over the gauge angle is performed explicitly. It provides the algebraic forms of the single particle Hamiltonian and of the pairing field entering generalized Hartree{endash}Fock{endash}Bogoljubov equations. Contrary to most approximations, the validity of the expressions for the energy and mean values of operators thus obtained is not a priori restricted where the fluctuation of the operator associated with the broken symmetry is large. We also derive the first-order correction to the pairing-order parameter. We test the quality of the proposed method on a non-trivial soluble model. {copyright} 1997 Academic Press, Inc.

  15. On the Restoration of Symmetry in Paired Fermion Systems

    NASA Astrophysics Data System (ADS)

    Flocard, H.; Onishi, N.

    1997-03-01

    We consider the problem of symmetry restoration as treated by the method of variation after projection (VAP) on good quantum numbers. We show that for compact groups, the convergence of the connected-linked expansion of the VAP kernels over the physically relevant interval of integration of the pairing gauge angle is not guaranteed. We propose instead a method which generates approximations of increasing precision which are periodic with respect to the gauge angle while differing from truncations of the Fourier expansion of the VAP kernels. For the projection on good particle number in paired fermion systems, this new approach is shown to be equivalent to an expansion in powers of the pairing tensor. For the lowest order approximation, an analytical integration over the gauge angle is performed explicitly. It provides the algebraic forms of the single particle Hamiltonian and of the pairing field entering generalized Hartree-Fock-Bogoljubov equations. Contrary to most approximations, the validity of the expressions for the energy and mean values of operators thus obtained is not a priori restricted where the fluctuation of the operator associated with the broken symmetry is large. We also derive the first-order correction to the pairing-order parameter. We test the quality of the proposed method on a non-trivial soluble model.

  16. Electrostatic solitary waves in dusty pair-ion plasmas

    SciTech Connect

    Misra, A. P.; Adhikary, N. C.

    2013-10-15

    The propagation of electrostatic waves in an unmagnetized collisionless pair-ion plasma with immobile positively charged dusts is studied for both large- and small-amplitude perturbations. Using a two-fluid model for pair-ions, it is shown that there appear two linear ion modes, namely the “fast” and “slow” waves in dusty pair-ion plasmas. The properties of these wave modes are studied with different mass (m) and temperature (T) ratios of negative to positive ions, as well as the effects of immobile charged dusts (δ). For large-amplitude waves, the pseudopotential approach is performed, whereas the standard reductive perturbation technique is used to study the small-amplitude Korteweg-de Vries (KdV) solitons. The profiles of the pseudopotential, the large amplitude solitons as well as the dynamical evolution of KdV solitons, are numerically studied with the system parameters as above. It is found that the pair-ion plasmas with positively charged dusts support the propagation of solitary waves (SWs) with only the negative potential. The results may be useful for the excitation of SWs in laboratory dusty pair-ion plasmas, electron-free industrial plasmas as well as for observation in space plasmas where electron density is negligibly small compared to that of negative ions.

  17. Temperature-dependent isovector pairing gap equations using a path integral approach

    SciTech Connect

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

    2007-10-15

    Temperature-dependent isovector neutron-proton (np) pairing gap equations have been established by means of the path integral approach. These equations generalize the BCS ones for the pairing between like particles at finite temperature. The method has been numerically tested using the one-level model. It has been shown that the gap parameter {delta}{sub np} has a behavior analogous to that of {delta}{sub nn} and {delta}{sub pp} as a function of the temperature: one notes the presence of a critical temperature. Moreover, it has been shown that the isovector pairing effects remain beyond the critical temperature that corresponds to the pairing between like particles.

  18. Perturbations of vortex ring pairs

    NASA Astrophysics Data System (ADS)

    Gubser, Steven S.; Horn, Bart; Parikh, Sarthak

    2016-02-01

    We study pairs of coaxial vortex rings starting from the action for a classical bosonic string in a three-form background. We complete earlier work on the phase diagram of classical orbits by explicitly considering the case where the circulations of the two vortex rings are equal and opposite. We then go on to study perturbations, focusing on cases where the relevant four-dimensional transfer matrix splits into two-dimensional blocks. When the circulations of the rings have the same sign, instabilities are mostly limited to wavelengths smaller than a dynamically generated length scale at which single-ring instabilities occur. When the circulations have the opposite sign, larger wavelength instabilities can occur.

  19. Pair Cascades in Blazars and Radio Galaxies

    NASA Astrophysics Data System (ADS)

    Roustazadeh Sheikhyousefi, Parisa

    2012-05-01

    magnetic field in the AGN environment, secondary particles produced by gamma-gamma absorption can be isotropized. I suggested that the Compton emission from VHE gamma-ray induced pair cascades can explain the detection of radio galaxies as high energy sources. I presented fits to the the Fermi fluxes and spectra of the radio galaxies Cen A and NGC 1275. In the last part of my Ph. D. research work, I developed my Monte-Carlo code to include energy loss of particles by synchrotron radiation between to successive Compton scatterings and the angle dependence of the synchrotron output from the cascade. This can be important for situations when the magnetic field in the AGN environment is not negligible. I showed that the synchrotron radiation from the cascades in the radio galaxies NGC 1275 and Cen A with the parameters used in my first and second paper are much smaller than the synchrotron radiation from the jets and neglecting synchrotron radiation in those works is justified. I found that the magnetic field can not be determined from a fit of the cascade emission to the gamma-ray spectrum alone. I studied this scenario for the case of NGC 1275 and showed that the degeneracy of the magnetic field can only be lifted if the synchrotron emission from the cascade is observed as well. I suggest that the big blue bump (BBB) observed in the spectral energy distribution (SED) of several blazars can be due to the synchrotron radiation from cascades. This can be an alternative explanation of the BBB signature and I illustrate this idea on the blazar 3C 279. I have investigated the apparent absorption feature observed in the SEDs of some blazars such as W Comae and S5 0716+714 in the 10-100 GeV energy range and point out that this can be due to gamma-gamma absorption of primary gamma-ray photons by soft photons from the BLR or dust torus. During this study, I participated in three observing runs at the MDM observatory on Kitt Peak near Tucson, Arizona and I monitored the optical

  20. Pilocarpine modulates the cellular electrical properties of mammalian hearts by activating a cardiac M3 receptor and a K+ current

    PubMed Central

    Wang, Huizhen; Shi, Hong; Lu, Yanjie; Yang, Baofeng; Wang, Zhiguo

    1999-01-01

    Pilocarpine, a muscarinic acetylcholine receptor (mAChR) agonist, is widely used for treatment of xerostomia and glaucoma. It can also cause many other cellular responses by activating different subtypes of mAChRs in different tissues. However, the potential role of pilocarpine in modulating cardiac function remained unstudied.We found that pilocarpine produced concentration-dependent (0.1–10 μM) decrease in sinus rhythm and action potential duration, and hyperpolarization of membrane potential in guinea-pig hearts. The effects were nearly completely reversed by 1 μM atropine or 2 nM 4DAMP methiodide (an M3-selective antagonist).Patch-clamp recordings in dispersed myocytes from guinea-pig and canine atria revealed that pilocarpine induces a novel K+ current with delayed rectifying properties. The current was suppressed by low concentrations of M3-selective antagonists 4DAMP methiodide (2–10 nM), 4DAMP mustard (4–20 nM, an ackylating agent) and p-F-HHSiD (20–200 nM). Antagonists towards other subtypes (M1, M2 or M4) all failed to alter the current.The affinity of pilocarpine (KD) at mAChRs derived from displacement binding of [3H]-NMS in the homogenates from dog atria was 2.2 μM (65% of the total binding) and that of 4DAMP methiodide was 2.8 nM (70% of total binding), consistent with the concentration of pilocarpine needed for the current induction and for the modulation of the cardiac electrical activity and the concentration of 4DAMP to block pilocarpine effects.Our data indicate, for the first time, that pilocarpine modulates the cellular electrical properties of the hearts, likely by activating a K+ current mediated by M3 receptors. PMID:10372814

  1. Scale-up of industrial biodiesel production to 40 m(3) using a liquid lipase formulation.

    PubMed

    Price, Jason; Nordblad, Mathias; Martel, Hannah H; Chrabas, Brent; Wang, Huali; Nielsen, Per Munk; Woodley, John M

    2016-08-01

    In this work, we demonstrate the scale-up from an 80 L fed-batch scale to 40 m(3) along with the design of a 4 m(3) continuous process for enzymatic biodiesel production catalyzed by NS-40116 (a liquid formulation of a modified Thermomyces lanuginosus lipase). Based on the analysis of actual pilot plant data for the transesterification of used cooking oil and brown grease, we propose a method applying first order integral analysis to fed-batch data based on either the bound glycerol or free fatty acid content in the oil. This method greatly simplifies the modeling process and gives an indication of the effect of mixing at the various scales (80 L to 40 m(3) ) along with the prediction of the residence time needed to reach a desired conversion in a CSTR. Suitable process metrics reflecting commercial performance such as the reaction time, enzyme efficiency, and reactor productivity were evaluated for both the fed-batch and CSTR cases. Given similar operating conditions, the CSTR operation on average, has a reaction time which is 1.3 times greater than the fed-batch operation. We also showed how the process metrics can be used to quickly estimate the selling price of the enzyme. Assuming a biodiesel selling price of 0.6 USD/kg and a one-time use of the enzyme (0.1% (w/woil ) enzyme dosage); the enzyme can then be sold for 30 USD/kg which ensures that that the enzyme cost is not more than 5% of the biodiesel revenue. Biotechnol. Bioeng. 2016;113: 1719-1728. © 2016 Wiley Periodicals, Inc.

  2. Adsorption of aromatics on the (111) surface of PtM and PtM3 (M = Fe, Ni) alloys

    SciTech Connect

    Hensley, Alyssa; Schneider, Sebastian; Wang, Yong; McEwen, Jean-Sabin

    2015-09-18

    The adsorption of benzene and phenol was studied on PtM and PtM3 (111) surfaces, with M being either Ni or Fe. Under vacuum, the most favorable near surface structures showed an enrichment in Pt over the M species. An analysis of the electronic structure of the metal species in the clean surfaces with different near surface structures was done with the d-band model and showed that the Pt's d-states are significantly shifted away from the Fermi level due to the Pt-M interactions while the M species' d-states were less affected, with Ni's d-band shifting closer to the Fermi level and Fe's d-band shifting away from the Fermi level. The adsorption of aromatics, benzene and phenol, on several near surface structures for the PtM and PtM3 (111) surfaces showed that higher surface M concentrations resulted in a stronger adsorption due to the larger amount of charge transferred between the adsorbate and surface. However, compared to the adsorption of benzene and phenol on monometallic surfaces, the adsorption of these species on the PtM and PtM3 (111) surfaces was significantly weakened. Overall, our results show that the observed behavior of these Pt/Fe and Pt/Ni alloys is similar to that seen for the previously studied Pd/Fe surfaces. Furthermore, balancing the weakly adsorbing Pt surface species with the more strongly interacting Fe or Ni species can lead to the tailored adsorption of aromatics with applications in both hydrodeoxygenation and hydrogenation reactions by increasing the desorption rate of wanted aromatic products.

  3. Scale-up of industrial biodiesel production to 40 m(3) using a liquid lipase formulation.

    PubMed

    Price, Jason; Nordblad, Mathias; Martel, Hannah H; Chrabas, Brent; Wang, Huali; Nielsen, Per Munk; Woodley, John M

    2016-08-01

    In this work, we demonstrate the scale-up from an 80 L fed-batch scale to 40 m(3) along with the design of a 4 m(3) continuous process for enzymatic biodiesel production catalyzed by NS-40116 (a liquid formulation of a modified Thermomyces lanuginosus lipase). Based on the analysis of actual pilot plant data for the transesterification of used cooking oil and brown grease, we propose a method applying first order integral analysis to fed-batch data based on either the bound glycerol or free fatty acid content in the oil. This method greatly simplifies the modeling process and gives an indication of the effect of mixing at the various scales (80 L to 40 m(3) ) along with the prediction of the residence time needed to reach a desired conversion in a CSTR. Suitable process metrics reflecting commercial performance such as the reaction time, enzyme efficiency, and reactor productivity were evaluated for both the fed-batch and CSTR cases. Given similar operating conditions, the CSTR operation on average, has a reaction time which is 1.3 times greater than the fed-batch operation. We also showed how the process metrics can be used to quickly estimate the selling price of the enzyme. Assuming a biodiesel selling price of 0.6 USD/kg and a one-time use of the enzyme (0.1% (w/woil ) enzyme dosage); the enzyme can then be sold for 30 USD/kg which ensures that that the enzyme cost is not more than 5% of the biodiesel revenue. Biotechnol. Bioeng. 2016;113: 1719-1728. © 2016 Wiley Periodicals, Inc. PMID:26806356

  4. Globular cluster photometry with the Hubble Space Telescope. 3: Blue stragglers and variable stars in the core of M3

    NASA Technical Reports Server (NTRS)

    Guhathakurta, Puragra; Yanny, Brian; Bahcall, John N.; Schneider, Donald P.

    1994-01-01

    This paper describes Hubble Space Telescope (HST)/Planetary Camera-I images of the core of the dense globular cluster M3 (NGC 5272). Stellar photometry in the F555W (V) and F785LP (I) bands, with a 1-sigma photometric accuracy of about 0.1 mag, has been used to construct color-magnitude diagrams of about 4700 stars above the main-sequence turnoff within r less than or approximately equal to 1 min of the cluster center. We have also analyzed archival HST F336W (U) images of M3 obtained by the Wide Field/Planetary Camera-I Instrument Definition Team. The UVI data are used to identify 28 blue straggler (BS) stars within the central 0.29 sq. arcmin. The specific frequency of BSs in this region of M3, N(sub BS)/N(sub V less than (V(HB)+2)) = 0.094 +/- 0.019, is about a factor of 2 - 3 higher than that found by Bolte et al. in a recent ground-based study of the same region, but comparable to that seen in the sparse outer parts of the same cluster and in HST observations of the core of the higher density cluster 47 Tuc. The BSs in M3 are slightly more centrally concentrated than red giant branch stars while horizontal branch stars are somewhat less concentrated red giants. The radial distribution of V-selected subgiant and turnoff stars is well fit by a King model with a core radius r(sub core) = 28 arcmin +/- 2 arcmin (90% confidence limits), which corresponds to 1.4 pc. Red giant and horizontal branch stars selected in the ultraviolet data (U less than 18) have a somewhat more compact distribution (r(sub core) = 22.5 arcmin). The HST U data consist of 17 exposures acquired over a span of three days. We have used these data to isolate 40 variable stars for which relative astrometry, brightnesses, colors, and light curves are presented. A Kolmogorov-Smirnov test indicates that, typically, the variability for each star is significant at the 95% level. We identify two variable BS candidates (probably of the SX Phe type), out of a sample of approximately 25 BSs in which

  5. Successful management of pulmonary hemorrhage and aspergillosis in a patient with acute myeloid leukemia (AML-M3).

    PubMed

    Gunbatar, Hulya; Demir, Cengiz; Kara, Erdal; Esen, Ramazan; Sertogullarindan, Bunyamin; Asker, Selvi

    2015-01-01

    A 35-year-old man presented with a one month history of gingival bleeding. He was diagnosed with Acute Myeloid Leukemia (AML-M3). During treatment he developed alveolar hemorrhage for which he was treated with a steroid. After the steroid treatment he developed a nodule, a cavitary lesion and atelectasia in the left lung. He was treated with voriconazole. After therapy with voriconazole his lesion significantly decreased. This case illustrates the efficacy and safety of antifungal therapy with voriconazole for aspergillosis complicated by AML. PMID:26744658

  6. Successful management of pulmonary hemorrhage and aspergillosis in a patient with acute myeloid leukemia (AML-M3)

    PubMed Central

    Gunbatar, Hulya; Demir, Cengiz; Kara, Erdal; Esen, Ramazan; Sertogullarindan, Bunyamin; Asker, Selvi

    2015-01-01

    A 35-year-old man presented with a one month history of gingival bleeding. He was diagnosed with Acute Myeloid Leukemia (AML-M3). During treatment he developed alveolar hemorrhage for which he was treated with a steroid. After the steroid treatment he developed a nodule, a cavitary lesion and atelectasia in the left lung. He was treated with voriconazole. After therapy with voriconazole his lesion significantly decreased. This case illustrates the efficacy and safety of antifungal therapy with voriconazole for aspergillosis complicated by AML. PMID:26744658

  7. NMR study of the electric field gradient in the paramagnetic phase of M3V2O8 (M = Co, Ni) compounds

    NASA Astrophysics Data System (ADS)

    Smol'Nikov, A. G.; Ogloblichev, V. V.; Sadykov, A. F.; Piskunov, Yu. V.; Gerashchenko, A. P.; Verkhovskii, S. V.; Yakubovskii, A. Yu.; Barilo, S. N.; Bychkov, G. L.; Shiryaev, S. V.

    2011-06-01

    The NMR spectra and the decay of a spin echo signal from 51V nuclei in Kagome-staircase Co3V2O8 (CVO) and Ni3V2O8 (NVO) single crystals are measured in the temperature range 30-300 K and a magnetic field H 0 = 20 kOe. The orientation dependences of the 51V NMR line shape are used to determine the electric field gradient (EFG) parameters, namely, quadrupole frequency ν Q and asymmetry parameter η. These parameters for NVO and CVO are ν Q = 180(10) kHz, η = 0.5(1) and ν Q = 130(10) kHz, η = 0.6(1), respectively. A comparison of the results of calculating EFG tensors with a point charge model and the NMR data indicates that the crystallographically equivalent vanadium atoms in the Ni3V2O8 and Co3V2O8 compounds differ in the EFG axis orientation. M3V2O8 crystals are found to have vanadium positions (V1, V2) with different orientations of the z axis, which specifies the direction of the principal value of EFG ( V zz ): these orientations lie in the bc plane and make an angle of either +51(5)° (V1) or -51(5)° (V2) with axis c. In the temperature range 30-300 K, the EFG tensor components and the local symmetry of the charge surrounding of the vanadium positions in NVO and CVO oxides are found to change insignificantly.

  8. Characterization of hydromechanical stress in aerated stirred tanks up to 40 m3 scale by measurement of maximum stable drop size

    PubMed Central

    2014-01-01

    Background Turbulence intensity, or hydromechanical stress, is a parameter that influences a broad range of processes in the fields of chemical engineering and biotechnology. Fermentation processes are often characterized by high agitation and aeration intensity resulting in high gas void fractions of up to 20% in large scale reactors. Very little experimental data on hydromechanical stress for such operating conditions exists because of the problems associated with measuring hydromechanical stress under aeration and intense agitation. Results An indirect method to quantify hydromechanical stress for aerated operating conditions by the measurement of maximum stable drop size in a break-up controlled dispersion was applied to characterize hydromechanical stress in reactor scales of 50 L, 3 m3 and 40 m3 volume with a broad range of operating conditions and impeller geometries (Rushton turbines). Results for impellers within each scale for the ratio of maximum to specific energy dissipation rate ϕ based on measured values of maximum stable drop size for aerated operating conditions are qualitatively in agreement with results from literature correlations for unaerated operating conditions. Comparison of data in the different scales shows that there is a scale effect that results in higher values for ϕ in larger reactors. This behavior is not covered by the classic theory of turbulent drop dispersion but is in good agreement with the theory of turbulence intermittency. The data for all impeller configurations and all aeration rates for the three scales can be correlated within ±20% when calculated values for ϕ based on the measured values for dmax are used to calculate the maximum local energy dissipation rate. A correlation of the data for all scales and all impeller configurations in the form ϕ = 2.3∙(ϕunaerated)0.34∙(DR)0.543 is suggested that successfully models the influence of scale and impeller geometry on ϕ for aerated operating conditions

  9. Multiwire proportional chambers in M1 and M3 spectrometers of charmed baryon experiment (E781) at Fermilab

    SciTech Connect

    Kaya, Mithat; /Iowa U.

    1997-08-01

    The status of the multiwire proportional chambers in the FERMILAB E781 experiment and a general description of the readout system are given. This essay will describe the system of multiwire proportional chambers (MWPC) that are part of the Fermilab experiment E781 setup. Multiwire proportional chambers are often used in particle physics experiments because they can determine the position of charged particles very accurately (less than a millimeter). The E781 experiment which is also called SELEX (SEgmented LargE-X) is a spectrometer designed to study the production and decay of charmed baryons. MWPCs are part of the 3-stage charged particle spectrometer (Figure 1). Each spectrometer stage includes a bending magnet and chambers. More information about E781 experiment is given in the Appendix. In the following, some basic concepts of MWPCs will be given briefly. After that the multiwire proportional chambers (M1PWC and M3PWC) that are used in the E781 fixed target experiment will be described. Then a general description of the readout system for both M1PWC and M3PWC setups will follow. Finally the tests done on both sets of chambers will be explained in detail.

  10. M3-subtype muscarinic receptor that controls intracellular calcium release and inositol phosphate accumulation in gastric parietal cells.

    PubMed

    Leonard, A; Cuq, P; Magous, R; Bali, J P

    1991-07-25

    The muscarinic receptor subtype which triggers acid secretion was investigated in isolated rabbit gastric parietal cells. Cytosolic free Ca2+ concentration ([Ca2+]i), measured with the fluorescent indicator FURA-2, increased rapidly after full agonist (carbachol) stimulation (6-8 sec), then returned to an intermediate sustained value. Other M2-agonists, oxotremorine and arecoline, produced a partial [Ca2+]i increase, whereas M1-agonists, pilocarpine and [4-m-chlorophenylcarbamoyloxyl]-2-butynyl-trimethylammonium, were without any significant effect. [Ca2+]i rise was inhibited by selective muscarinic antagonists: atropine greater than 4-diphenylacetoxy-N-methyl-piperidine methbromide greater than quinuclidinylbenzilate (QNB) greater than pirenzepine greater than 11-[[2-[(diethylamino)methyl]-1-piperidinyl]acetyl]-5,11-dihydro-6H- pyrido[2,3-b][1,4]benzodiazepine-6-one, this sequence being characteristic of the involvement of an M3-subtype. This inhibition was shown to be stereoselective; dexetimide and (-)QNB were more potent than levetimide and (+)QNB. The IC50 values for inhibition of [Ca2+]i increase by muscarinic antagonists were in good agreement with those obtained for inhibition of phospholipase C activation. In conclusion, the muscarinic receptor that controls acid secretion appears to be of the M3-subtype and the biochemical events coupled to the activation of this receptor system are also controlled through the same subtype. PMID:1651079

  11. Allosteric Effects of Sodium Ion Binding on Activation of the M3 Muscarinic G-Protein-Coupled Receptor

    PubMed Central

    Miao, Yinglong; Caliman, Alisha D.; McCammon, J. Andrew

    2015-01-01

    G-protein-coupled receptors (GPCRs) are important membrane proteins that mediate cellular signaling and represent primary targets for about one-third of currently marketed drugs. Recent x-ray crystallographic studies identified distinct conformations of GPCRs in the active and inactive states. An allosteric sodium ion was found bound to a highly conserved D2.50 residue in inactive GPCRs, whereas the D2.50 allosteric pocket became collapsed in active GPCR structures. However, the dynamic mechanisms underlying these observations remain elusive. In this study, we aimed to understand the mechanistic effects of sodium ion binding on dynamic activation of the M3 muscarinic GPCR through long-timescale accelerated molecular dynamics (aMD) simulations. Results showed that with the D2.50 residue deprotonated, the M3 receptor is bound by an allosteric sodium ion and confined mostly in the inactive state with remarkably reduced flexibility. In contrast, the D2.50-protonated receptor does not exhibit sodium ion binding to the D2.50 allosteric site and samples a significantly larger conformational space. The receptor activation is captured and characterized by large-scale structural rearrangements of the transmembrane helices via dynamic hydrogen bond and salt bridge interactions. The residue motions are highly correlated during receptor activation. Further network analysis revealed that the allosteric signaling between residue D2.50 and key residues in the intracellular, extracellular, and orthosteric pockets is significantly weakened upon sodium ion binding. PMID:25863070

  12. Report on Pairing-based Cryptography.

    PubMed

    Moody, Dustin; Peralta, Rene; Perlner, Ray; Regenscheid, Andrew; Roginsky, Allen; Chen, Lily

    2015-01-01

    This report summarizes study results on pairing-based cryptography. The main purpose of the study is to form NIST's position on standardizing and recommending pairing-based cryptography schemes currently published in research literature and standardized in other standard bodies. The report reviews the mathematical background of pairings. This includes topics such as pairing-friendly elliptic curves and how to compute various pairings. It includes a brief introduction to existing identity-based encryption (IBE) schemes and other cryptographic schemes using pairing technology. The report provides a complete study of the current status of standard activities on pairing-based cryptographic schemes. It explores different application scenarios for pairing-based cryptography schemes. As an important aspect of adopting pairing-based schemes, the report also considers the challenges inherent in validation testing of cryptographic algorithms and modules. Based on the study, the report suggests an approach for including pairing-based cryptography schemes in the NIST cryptographic toolkit. The report also outlines several questions that will require further study if this approach is followed.

  13. Report on Pairing-based Cryptography

    PubMed Central

    Moody, Dustin; Peralta, Rene; Perlner, Ray; Regenscheid, Andrew; Roginsky, Allen; Chen, Lily

    2015-01-01

    This report summarizes study results on pairing-based cryptography. The main purpose of the study is to form NIST’s position on standardizing and recommending pairing-based cryptography schemes currently published in research literature and standardized in other standard bodies. The report reviews the mathematical background of pairings. This includes topics such as pairing-friendly elliptic curves and how to compute various pairings. It includes a brief introduction to existing identity-based encryption (IBE) schemes and other cryptographic schemes using pairing technology. The report provides a complete study of the current status of standard activities on pairing-based cryptographic schemes. It explores different application scenarios for pairing-based cryptography schemes. As an important aspect of adopting pairing-based schemes, the report also considers the challenges inherent in validation testing of cryptographic algorithms and modules. Based on the study, the report suggests an approach for including pairing-based cryptography schemes in the NIST cryptographic toolkit. The report also outlines several questions that will require further study if this approach is followed. PMID:26958435

  14. Report on Pairing-based Cryptography.

    PubMed

    Moody, Dustin; Peralta, Rene; Perlner, Ray; Regenscheid, Andrew; Roginsky, Allen; Chen, Lily

    2015-01-01

    This report summarizes study results on pairing-based cryptography. The main purpose of the study is to form NIST's position on standardizing and recommending pairing-based cryptography schemes currently published in research literature and standardized in other standard bodies. The report reviews the mathematical background of pairings. This includes topics such as pairing-friendly elliptic curves and how to compute various pairings. It includes a brief introduction to existing identity-based encryption (IBE) schemes and other cryptographic schemes using pairing technology. The report provides a complete study of the current status of standard activities on pairing-based cryptographic schemes. It explores different application scenarios for pairing-based cryptography schemes. As an important aspect of adopting pairing-based schemes, the report also considers the challenges inherent in validation testing of cryptographic algorithms and modules. Based on the study, the report suggests an approach for including pairing-based cryptography schemes in the NIST cryptographic toolkit. The report also outlines several questions that will require further study if this approach is followed. PMID:26958435

  15. Supergranular Parameters

    NASA Astrophysics Data System (ADS)

    Udayashankar, Paniveni

    2016-07-01

    I study the complexity of supergranular cells using intensity patterns from Kodaikanal solar observatory. The chaotic and turbulent aspect of the solar supergranulation can be studied by examining the interrelationships amongst the parameters characterizing supergranular cells namely size, horizontal flow field, lifetime and physical dimensions of the cells and the fractal dimension deduced from the size data. The findings are supportive of Kolmogorov's theory of turbulence. The Data consists of visually identified supergranular cells, from which a fractal dimension 'D' for supergranulation is obtained according to the relation P α AD/2 where 'A' is the area and 'P' is the perimeter of the supergranular cells. I find a fractal dimension close to about 1.3 which is consistent with that for isobars and suggests a possible turbulent origin. The cell circularity shows a dependence on the perimeter with a peak around (1.1-1.2) x 105 m. The findings are supportive of Kolmogorov's theory of turbulence.

  16. FIR statistics of paired galaxies

    NASA Technical Reports Server (NTRS)

    Sulentic, Jack W.

    1990-01-01

    Much progress has been made in understanding the effects of interaction on galaxies (see reviews in this volume by Heckman and Kennicutt). Evidence for enhanced emission from galaxies in pairs first emerged in the radio (Sulentic 1976) and optical (Larson and Tinsley 1978) domains. Results in the far infrared (FIR) lagged behind until the advent of the Infrared Astronomy Satellite (IRAS). The last five years have seen numerous FIR studies of optical and IR selected samples of interacting galaxies (e.g., Cutri and McAlary 1985; Joseph and Wright 1985; Kennicutt et al. 1987; Haynes and Herter 1988). Despite all of this work, there are still contradictory ideas about the level and, even, the reality of an FIR enhancement in interacting galaxies. Much of the confusion originates in differences between the galaxy samples that were studied (i.e., optical morphology and redshift coverage). Here, the authors report on a study of the FIR detection properties for a large sample of interacting galaxies and a matching control sample. They focus on the distance independent detection fraction (DF) statistics of the sample. The results prove useful in interpreting the previously published work. A clarification of the phenomenology provides valuable clues about the physics of the FIR enhancement in galaxies.

  17. Phenomenology of transionospheric pulse pairs: Further observations

    SciTech Connect

    Massey, R.S.; Holden, D.N.; Shao, X.

    1998-11-01

    We report on further observations of transionospheric pulse pairs (TIPPs), which are the most powerful transient radio signals observed by the Blackbeard broadband digital radio receiver on the ALEXIS satellite. The source of these signals is unknown but appears to be associated with thunderstorm activity. The signals do not resemble those reported for known lightning processes. We have previously reported observations of these events in the frequency band 28{endash}95 MHz. In this paper we report observations of TIPPs in the 117- to 166-MHz band, with the subsatellite point situated over the contiguous United States. The main results are that the measured pulse parameter statistics are nearly the same as reported for the low-frequency events, with the exception that the pulse separation distribution is biased toward smaller values in the high-frequency observations. The radiated power does not drop off appreciably even at 166 MHz, which further constrains the possible size and timescale of the source(s). We also report results of experiments designed to measure the apparent reflectivity of dry, flat ground at frequencies around 100 MHz. We find that the apparent reflectivity can exceed 90{percent}. This result helps to explain how the second pulse in a TIPP can have so much energy relative to the first. {copyright} 1998 American Geophysical Union

  18. FAST TRACK COMMUNICATION: A Lax pair for a lattice modified KdV equation, reductions to q-Painlevé equations and associated Lax pairs

    NASA Astrophysics Data System (ADS)

    Hay, Mike; Hietarinta, Jarmo; Joshi, Nalini; Nijhoff, Frank

    2007-01-01

    We present a new, nonautonomous Lax pair for a lattice nonautomous modified Korteweg deVries equation and show that it can be consistently extended multi-dimensionally, a property commonly referred to as being consistent around a cube. This nonautonomous equation is reduced to a series of q-discrete Painlevé equations, and Lax pairs for the reduced equations are found. A 2 × 2 Lax pair is given for a \\qth with multiple parameters and, also, for versions of \\qtw and \\qfi , all for the first time.

  19. The first rubidium rare-earth(III) thiophosphates: Rb 3M3[PS 4] 4 ( M=Pr, Er)

    NASA Astrophysics Data System (ADS)

    Komm, Theresa; Schleid, Thomas

    2005-02-01

    The two non-isotypical rubidium rare-earth(III) thiophosphates Rb 3M3[PS 4] 4 of praseodymium and erbium can easily be obtained by the stoichiometric reaction of the respective rare-earth metal, red phosphorus and sulfur with an excess of rubidium bromide (RbBr) as flux and rubidium source at 950°C for 14 days in evacuated silica tubes. The pale green platelet-shaped single crystals of Rb 3Pr 3[PS 4] 4 as well as the pink rods of Rb 3Er 3[PS 4] 4 are moisture sensitive. Rb 3Pr 3[PS 4] 4 crystallizes triclinically in the space group P1¯ ( a=926.79(5) pm, b=1050.83(5) pm, c=1453.28(7) pm, α=84.329(4)°, β=88.008(4)°, γ=80.704(4)°; Z=2), Rb 3Er 3[PS 4] 4 monoclinically in the space group P21/n ( a=915.97(5) pm, b=1575.86(7) pm, c=1843.32(9) pm, β=95.601(6)°; Z=4). In both structures, there are three crystallographically different rare-earth cations present. ( M1) 3+ is eightfold coordinated in the shape of a square antiprism, ( M2) 3+ and ( M3) 3+ are both surrounded by eight sulfur atoms as bicapped trigonal prisms each with a coordination number of eight as well as for the praseodymium, but better described as CN=7+1 in the case of the erbium compound. These [ MS 8] 13- polyhedra form a layer according to ∞2{[M3[PS]4]} by sharing edges with the isolated [PS 4] 3- tetrahedra ( d(P-S)=200-209 pm, ∢(S-P-S)=102-116°). These layers are stacked with a repetition period of three in the case of the praseodymium compound, but of only two for the erbium analog. The rubidium cation (Rb1) + is located in cavities of these layers and tenfold coordinated in the shape of a tetracapped trigonal antiprism. The also tenfold but more irregularly coordinated rubidium cations (Rb2) + and (Rb3) + reside between the layers.

  20. Pair programming in education: a literature review

    NASA Astrophysics Data System (ADS)

    Hanks, Brian; Fitzgerald, Sue; McCauley, Renée; Murphy, Laurie; Zander, Carol

    2011-06-01

    This article provides a review of educational research literature focused on pair programming in the undergraduate computer science curriculum. Research suggests that the benefits of pair programming include increased success rates in introductory courses, increased retention in the major, higher quality software, higher student confidence in solutions, and improvement in learning outcomes. Moreover, there is some evidence that women, in particular, benefit from pair programming. The literature also provides evidence that the transition from paired to solo programming is easy for students. The greatest challenges for paired students appear to concern scheduling and partner compatibility. This review also considers practical issues such as assigning partners, teaching students to work in pairs, and assessing individual contributions, and concludes with a discussion of open research questions.

  1. Pair production and escape in accretion disks.

    NASA Astrophysics Data System (ADS)

    Meirelles Filho, C.; Liang, E. P.

    It is shown that, in the absence of confining mechanisms, there will be a non-negligible amount of pairs escaping from the inner region of a Comptonized soft photon two-temperature accretion disk, when pair production is not balanced by annihilation. Assuming conditions such that the photons and particles in the disk can be regarded as close to a Wien plasma (Svensson, 1984), the authors calculate the rate of pair escape from the disk for both a situation close to pair balance and a situation with the rate of escape exceeding annihilation. The pairs are assumed to be created by photon-photon processes. Within this model one can account for the 511 keV γ-ray luminosity due to pair annihilation in the ISM, as recently observed in the Einstein source.

  2. Helix 8 and the i3 Loop of the Muscarinic M3 Receptor Are Crucial Sites for Its Regulation by the Gβ5-RGS7 Complex

    PubMed Central

    2015-01-01

    The muscarinic M3 receptor (M3R) is a Gq-coupled receptor and is known to interact with many intracellular regulatory proteins. One of these molecules is Gβ5-RGS7, the permanently associated heterodimer of G protein β-subunit Gβ5 and RGS7, a regulator of G protein signaling. Gβ5-RGS7 can attenuate M3R-stimulated release of Ca2+ from intracellular stores or enhance the influx of Ca2+ across the plasma membrane. Here we show that deletion of amino acids 304–345 from the central portion of the i3 loop renders M3R insensitive to regulation by Gβ5-RGS7. In addition to the i3 loop, interaction of M3R with Gβ5-RGS7 requires helix 8. According to circular dichroism spectroscopy, the peptide corresponding to amino acids 548–567 in the C-terminus of M3R assumes an α-helical conformation. Substitution of Thr553 and Leu558 with Pro residues disrupts this α-helix and abolished binding to Gβ5-RGS7. Introduction of the double Pro substitution into full-length M3R (M3RTP/LP) prevents trafficking of the receptor to the cell surface. Using atropine or other antagonists as pharmacologic chaperones, we were able to increase the level of surface expression of the TP/LP mutant to levels comparable to that of wild-type M3R. However, M3R-stimulated calcium signaling is still severely compromised. These results show that the interaction of M3R with Gβ5-RGS7 requires helix 8 and the central portion of the i3 loop. PMID:25551629

  3. Helix 8 and the i3 loop of the muscarinic M3 receptor are crucial sites for its regulation by the Gβ5-RGS7 complex.

    PubMed

    Karpinsky-Semper, Darla; Tayou, Junior; Levay, Konstantin; Schuchardt, Brett J; Bhat, Vikas; Volmar, Claude-Henry; Farooq, Amjad; Slepak, Vladlen Z

    2015-02-01

    The muscarinic M3 receptor (M3R) is a Gq-coupled receptor and is known to interact with many intracellular regulatory proteins. One of these molecules is Gβ5-RGS7, the permanently associated heterodimer of G protein β-subunit Gβ5 and RGS7, a regulator of G protein signaling. Gβ5-RGS7 can attenuate M3R-stimulated release of Ca(2+) from intracellular stores or enhance the influx of Ca(2+) across the plasma membrane. Here we show that deletion of amino acids 304-345 from the central portion of the i3 loop renders M3R insensitive to regulation by Gβ5-RGS7. In addition to the i3 loop, interaction of M3R with Gβ5-RGS7 requires helix 8. According to circular dichroism spectroscopy, the peptide corresponding to amino acids 548-567 in the C-terminus of M3R assumes an α-helical conformation. Substitution of Thr553 and Leu558 with Pro residues disrupts this α-helix and abolished binding to Gβ5-RGS7. Introduction of the double Pro substitution into full-length M3R (M3R(TP/LP)) prevents trafficking of the receptor to the cell surface. Using atropine or other antagonists as pharmacologic chaperones, we were able to increase the level of surface expression of the TP/LP mutant to levels comparable to that of wild-type M3R. However, M3R-stimulated calcium signaling is still severely compromised. These results show that the interaction of M3R with Gβ5-RGS7 requires helix 8 and the central portion of the i3 loop.

  4. M3D-C1 simulations of plasma response in ELM-mitigated ASDEX Upgrade and DIII-D discharges

    NASA Astrophysics Data System (ADS)

    Lyons, B. C.; Ferraro, N. M.; Haskey, S. R.; Logan, N. C.

    2015-11-01

    The extended magnetohydrodynamics (MHD) code M3D-C1 is used to study the time-independent, linear response of tokamak equilibria to applied, 3D magnetic perturbations. In doing so, we seek to develop a more complete understanding of what MHD phenomena are responsible for the mitigation and suppression of edge-localized modes (ELMs) and to explain why the success of ELM suppression experiments differs both within a single tokamak and across different tokamaks. We consider such experiments on ASDEX Upgrade and DIII-D. We examine how resonant and non-resonant plasma responses are affected by varying the relative magnitude and phase of sets of magnetic coils. The importance of two-fluid effects, rotation profiles, plasma β, collisionality, bootstrap current profiles, and various numerical parameters are explored. The results are verified against other MHD codes (e.g., IPEC, MARS), correlated to observations of ELM mitigation or suppression, and validated against observed magnetic responses. Work supported in part by US DOE under DE-FC02-04ER54698, DE-AC02-09CH11466, and the FES Postdoctoral Research Program.

  5. The ultraviolet spectrum of noncoronal late-type stars - The Gamma Crucis (M3.4 III) reference spectrum

    NASA Technical Reports Server (NTRS)

    Carpenter, Kenneth G.; Pesce, Joseph E.; Stencel, Robert E.; Brown, Alexander; Johansson, Sveneric

    1988-01-01

    A guide is presented to the UV spectrum of M-type giants and supergiants whose outer atmospheres contain warm chromospheres but not coronae. The M3 giant Gamma Crucis is taken as the archetype of the cooler, oxygen-rich, noncoronal stars. Line identifications and integrated line flux measurements of the chromospheric emission features seen in the 1200-3200 A range of IUE high-resolution spectra are presented. The major fluorescence processes operating in the outer atmosphere of Gamma Crucis, including eight previously unknown pumping processes and 21 new fluorescent line products, are summarized, and the enhancements of selected line strengths by 'line leakage' is discussed. A set of absorption features toward the longer wavelength end of this range is identified which can be used to characterize the radial velocity of the stellar photospheres. The applicability of the results to the spectra of noncoronal stars with different effective temperatures and gravities is discussed.

  6. Anomalous Hall hysteresis in T m3F e5O12/Pt with strain-induced perpendicular magnetic anisotropy

    NASA Astrophysics Data System (ADS)

    Tang, Chi; Sellappan, Pathikumar; Liu, Yawen; Xu, Yadong; Garay, Javier E.; Shi, Jing

    2016-10-01

    We demonstrate robust interface strain-induced perpendicular magnetic anisotropy in atomically flat ferrimagnetic insulator T m3F e5O12 (TIG) films grown with pulsed laser deposition on a substituted G d3G a5O12 substrate which maximizes the tensile strain at the interface. In bilayers consisting of Pt and TIG, we observe large squared Hall hysteresis loops over a wide range of thicknesses of Pt at room temperature. When a thin Cu layer is inserted between Pt and TIG, the Hall hysteresis magnitude decays but stays finite as the thickness of Cu increases up to 5 nm. However, if the Cu layer is placed atop Pt instead, the Hall hysteresis magnitude is consistently larger than when the Cu layer with the same thickness is inserted in between for all Cu thicknesses. These results suggest that both the proximity-induced ferromagnetism and spin current contribute to the anomalous Hall effect.

  7. Multiple stellar populations in the globular cluster M3 (NGC 5272): a Strömgren perspective

    NASA Astrophysics Data System (ADS)

    Massari, Davide; Lapenna, Emilio; Bragaglia, Angela; Dalessandro, Emanuele; Contreras Ramos, Rodrigo; Amigo, Pía

    2016-06-01

    We present Strömgren photometry of the Galactic Globular Cluster M3 to study its multiple generations phenomenon. The use of different colour-magnitude diagrams (CMDs) and especially of the notoriously efficient cy index allowed us to detect a double red giant branch in the cluster CMD. After decontamination from fore- and background sources, the two sequences turned out to be equally populated. The two components also show a bimodal radial distribution well corresponding to that predicted by numerical simulations for clusters living in an intermediate dynamical evolutive state and with a population with modified chemical composition that was born more centrally concentrated than the primordial. The analysis of high-resolution spectra quantitatively demonstrates that the two detected sequences correspond to the first (Na-poor) generation and the second (Na-rich) generation, thus confirming the importance of synergy between photometry and spectroscopy.

  8. L-689,660, a novel cholinomimetic with functional selectivity for M1 and M3 muscarinic receptors.

    PubMed Central

    Hargreaves, R. J.; McKnight, A. T.; Scholey, K.; Newberry, N. R.; Street, L. J.; Hutson, P. H.; Semark, J. E.; Harley, E. A.; Patel, S.; Freedman, S. B.

    1992-01-01

    1. L-689,660, 1-azabicyclo[2.2.2]octane, 3-(6-chloropyrazinyl)maleate, a novel cholinomimetic, demonstrated high affinity binding (pKD (apparent) 7.42) at rat cerebral cortex muscarinic receptors. L-689,660 had a low ratio (34) of pKD (apparent) values for the displacement of binding of the antagonist ([3H]-N-methylscopolamine ([3H]-NMS) compared with the displacement of the agonist [3H]-oxotremorine-M ([3H]-Oxo-M), in rat cerebral cortex. Low NMS/Oxo-M ratios have been shown previously to be a characteristic of compounds that are low efficacy partial agonists with respect to stimulation of phosphatidyl inositol turnover in the cerebral cortex. 2. L-689,660 showed no muscarinic receptor subtype selectivity in radioligand binding assays but showed functional selectivity in pharmacological assays. At M1 muscarinic receptors in the rat superior cervical ganglion, L-689,660 was a potent (pEC50 7.3 +/- 0.2) full agonist in comparison with (+/-)-muscarine. At M3 receptors in the guinea-pig ileum myenteric plexus-longitudinal muscle or in trachea, L-689,660 was again a potent agonist (pEC50 7.5 +/- 0.2 and 7.7 +/- 0.3 respectively) but had a lower maximum response than carbachol. In contrast L-689,660 was an antagonist at M2 receptors in guinea-pig atria (pA2 7.2 (95% confidence limits 7, 7.4)) and at muscarinic autoreceptors in rat hippocampal slices. 3. The putative M1-selective muscarinic agonist, AF102B (cis-2-methylspiro-(1,3-oxathiolane 5,3')-quinuclidine hydrochloride) was found to have a profile similar to L-689,660 but had up to 100 times less affinity in binding and functional assays.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1422595

  9. Activation of T84 cell chloride channels by carbachol involves a phosphoinositide-coupled muscarinic M3 receptor.

    PubMed

    Dickinson, K E; Frizzell, R A; Sekar, M C

    1992-04-10

    Muscarinic agonists stimulate Cl- secretion across monolayers of the colon tumor epithelial cell line, T84. The muscarinic receptor has been characterized in T84 cell homogenates by radioligand binding using [3H]N-methylscopolamine ([3H]NMS). [3H]NMS bound to a single population of sites at 25 degrees C in 100 mM NaCl, 20 mM HEPES, 10 mM MgCl2, pH 7.4 buffer, with calculated Kd = 278 (+/- 44) pM and Bmax = 40 (+/- 6) fmol/mg protein (n = 4). Binding was reversible (diss. t1/2 = 18 +/- 3 min) and stereoselective (dexetimide Ki = 0.3 nM) much greater than levetimide (Ki = 8300 nM). Antagonists exhibited the following rank order of potencies and Ki values (nM): atropine (0.54) greater than 4-diphenylacetoxy-N-methylpiperidine methobromide (4-DAMP) (0.84) greater than dicyclomine (14) = hexahydrosiladifenidol (18) greater than pirenzepine (136) greater than AF-DX 116 (3610). The same sequence was observed for inhibition of carbachol-induced 125I efflux from T84 monolayers. This is indicative of an M3 'glandular' muscarinic receptor. Coupling to second messenger systems was examined by labelling monolayers with [14C]arachidonic acid (AA) or [3H]inositol. Carbachol (0.3 mM) did not release [14C]AA from labelled lipids, but ionomycin produced a dose-dependent increase in media [14C]AA. Carbachol (0.3 mM) elevated inositol monophosphate 14-fold. The results suggest that muscarinic agonists stimulate Cl- secretion by interacting with an M3 receptor coupled to inositide lipid hydrolysis. PMID:1379932

  10. Lax pairs for deformed Minkowski spacetimes

    NASA Astrophysics Data System (ADS)

    Kyono, Hideki; Sakamoto, Jun-ichi; Yoshida, Kentaroh

    2016-01-01

    We proceed to study Yang-Baxter deformations of 4D Minkowski spacetime based on a conformal embedding. We first revisit a Melvin background and argue a Lax pair by adopting a simple replacement law invented in 1509.00173. This argument enables us to deduce a general expression of Lax pair. Then the anticipated Lax pair is shown to work for arbitrary classical r-matrices with Poincaré generators. As other examples, we present Lax pairs for pp-wave backgrounds, the Hashimoto-Sethi background, the Spradlin-Takayanagi-Volovich background.

  11. Driven quantum tunneling and pair creation with graphene Landau levels

    NASA Astrophysics Data System (ADS)

    Gagnon, Denis; Fillion-Gourdeau, François; Dumont, Joey; Lefebvre, Catherine; MacLean, Steve

    2016-05-01

    Driven tunneling between graphene Landau levels is theoretically linked to the process of pair creation from vacuum, a prediction of quantum electrodynamics (QED). Landau levels are created by the presence of a strong, constant, quantizing magnetic field perpendicular to a graphene monolayer. Following the formal analogy between QED and the description of low-energy excitations in graphene, solutions of the fully interacting Dirac equation are used to compute electron-hole pair creation driven by a circularly or linearly polarized field. This is achieved via the coupled channel method, a numerical scheme for the solution of the time-dependent Dirac equation in the presence of bound states. The case of a monochromatic driving field is first considered, followed by the more realistic case of a pulsed excitation. We show that the pulse duration yields an experimental control parameter over the maximal pair yield. Orders of magnitude of the pair yield are given for experimentally achievable magnetic fields and laser intensities weak enough to preserve the Landau level structure.

  12. Inferring relationships between pairs of individuals from locus heterozygosities

    PubMed Central

    Presciuttini, Silvano; Toni, Chiara; Tempestini, Elena; Verdiani, Simonetta; Casarino, Lucia; Spinetti, Isabella; Stefano, Francesco De; Domenici, Ranieri; Bailey-Wilson, Joan E

    2002-01-01

    Background The traditional exact method for inferring relationships between individuals from genetic data is not easily applicable in all situations that may be encountered in several fields of applied genetics. This study describes an approach that gives affordable results and is easily applicable; it is based on the probabilities that two individuals share 0, 1 or both alleles at a locus identical by state. Results We show that these probabilities (zi) depend on locus heterozygosity (H), and are scarcely affected by variation of the distribution of allele frequencies. This allows us to obtain empirical curves relating zi's to H for a series of common relationships, so that the likelihood ratio of a pair of relationships between any two individuals, given their genotypes at a locus, is a function of a single parameter, H. Application to large samples of mother-child and full-sib pairs shows that the statistical power of this method to infer the correct relationship is not much lower than the exact method. Analysis of a large database of STR data proves that locus heterozygosity does not vary significantly among Caucasian populations, apart from special cases, so that the likelihood ratio of the more common relationships between pairs of individuals may be obtained by looking at tabulated zi values. Conclusions A simple method is provided, which may be used by any scientist with the help of a calculator or a spreadsheet to compute the likelihood ratios of common alternative relationships between pairs of individuals. PMID:12441003

  13. The Statistical Power of the Cluster Randomized Block Design with Matched Pairs--A Simulation Study

    ERIC Educational Resources Information Center

    Dong, Nianbo; Lipsey, Mark

    2010-01-01

    This study uses simulation techniques to examine the statistical power of the group- randomized design and the matched-pair (MP) randomized block design under various parameter combinations. Both nearest neighbor matching and random matching are used for the MP design. The power of each design for any parameter combination was calculated from…

  14. [Structural and Dipole Structure Peculiarities of Hoogsteen Base Pairs Formed in Complementary Nucleobases according to ab initio Quantum Mechanics Studies].

    PubMed

    Petrenko, Y M

    2015-01-01

    Ab initio quantum mechanics studies for the detection of structure and dipole structure peculiarities of Hoogsteen base pairs relative to Watson-Crick base pairs, were performed during our work. These base pairs are formed as a result of complementary interactions. It was revealed, that adenine-thymine Hoogsteen base pair and adenine-thymine Watson-Crick base pairs can be formed depending on initial configuration. Cytosine-guanine Hoogsteen pairs are formed only when cytosine was originally protonated. Both types of Hoogsteen pairs have noticeable difference in the bond distances and angles. These differences appeared in purine as well as in pyrimidine parts of the pairs. Hoogsteen pairs have mostly shorter hydrogen bond lengths and significantly larger angles of hydrogen bonds and larger angles between the hydrogen bonds than Watson-Crick base pairs. Notable differences are also observed with respect to charge distribution and dipole moment. Quantitative data on these differences are shown in our work. It is also reported that the values of local parameters (according to Cambridge classification of the parameters which determine DNA properties) in Hoogsteen base pairs, are greatly different from Watson-Crick ones.

  15. Magnetic and structural phase transitions of multiferroic boracites M3B7O13X (M =3 d transition metal Cr-Zn or Mg; X =halogen Cl, Br, I)

    NASA Astrophysics Data System (ADS)

    Schnelle, Walter; Schmid, Hans

    2015-05-01

    The specific heat capacity of mostly single-crystalline samples of 21 boracite compounds M3B7O13X with M a 3 d transition metal (Cr, Mn, Fe, Co, Ni, Cu, Zn) or Mg and X a halogen (Cl, Br, I) is determined. In combination with magnetic susceptibility data the magnetic ordering of the M2 + ions at TN is investigated in detail. The fully ferroelectric/fully ferroelastic structural phase transitions at higher temperatures are measured by differential scanning calorimetry. In the Cr-Br, Cr-I, Cu-Cl, and Cu-Br compounds, previously unknown magnetic phases were found. Magnetic order in the boracites is characterized by the quantum and classical spin states of the M2 + ions, a variable degree of structural distortion, orbital effects, and competing exchange interactions. The Cu-Cl, Cu-Br, and Ni-Cl boracites exhibit broad maxima of magnetic specific heat and of magnetic susceptibility above TN caused by low-dimensional or frustrated magnetic interactions. Co boracites display additional broad anomalies below TN originating from continuous spin reorientations and effective S =1 /2 ground states. Indications for spin reorientations are also observed for Fe boracites. New phases appear in high magnetic fields for some Co and Fe boracites, which is not the case for the Mn compounds. Stronger magnetic frustration is deduced for the cubic Cr compounds. For the latter compounds and Ni-I boracite magnetostructural phase transitions are observed.

  16. Pair Programming in Education: A Literature Review

    ERIC Educational Resources Information Center

    Hanks, Brian; Fitzgerald, Sue; McCauley, Renee; Murphy, Laurie; Zander, Carol

    2011-01-01

    This article provides a review of educational research literature focused on pair programming in the undergraduate computer science curriculum. Research suggests that the benefits of pair programming include increased success rates in introductory courses, increased retention in the major, higher quality software, higher student confidence in…

  17. 22 CFR 62.31 - Au pairs.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... pair participant with child development and child safety instruction, as follows: (1) Prior to... development instruction of which no less than 4 shall be devoted to specific training for children under the... and participate directly in the home life of the host family. All au pair participants provide...

  18. 22 CFR 62.31 - Au pairs.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... pair participant with child development and child safety instruction, as follows: (1) Prior to... development instruction of which no less than 4 shall be devoted to specific training for children under the... and participate directly in the home life of the host family. All au pair participants provide...

  19. 22 CFR 62.31 - Au pairs.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... pair participant with child development and child safety instruction, as follows: (1) Prior to... development instruction of which no less than 4 shall be devoted to specific training for children under the... and participate directly in the home life of the host family. All au pair participants provide...

  20. 22 CFR 62.31 - Au pairs.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... pair participant with child development and child safety instruction, as follows: (1) Prior to... development instruction of which no less than 4 shall be devoted to specific training for children under the... and participate directly in the home life of the host family. All au pair participants provide...

  1. 22 CFR 62.31 - Au pairs.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... pair participant with child development and child safety instruction, as follows: (1) Prior to... development instruction of which no less than 4 shall be devoted to specific training for children under the... and participate directly in the home life of the host family. All au pair participants provide...

  2. Top Quark Pair Production at the Tevatron

    SciTech Connect

    Nielsen, Jason

    2005-05-17

    The measurement of the top quark pair production crosssection inproton-antiproton collisions at 1.96 TeV is a test ofquantumchromodynamics and could potentially be sensitive to newphysics beyondthe standard model. I report on the latest t-tbarcross section resultsfrom the CDF and DZero experiments in various finalstate topologies whicharise from decays of top quark pairs.

  3. Attitudes on Using Pair-Programming

    ERIC Educational Resources Information Center

    Howard, Elizabeth V.

    2007-01-01

    During a research study conducted over four semesters, students enrolled in an introductory programming class at a commuter campus used the pair-programming approach for both in-class labs and out-of-class programming assignments. This study was a comprehensive assessment of pair-programming using multiple measures of both quantitative and…

  4. Bidirectional Synonym Ratings of 464 Noun Pairs.

    ERIC Educational Resources Information Center

    Whitten, William B.; And Others

    1979-01-01

    Each of 464 noun pairs was rated for synonymy on a seven-point scale by college students to provide an extensive set of synonym pairs for use as stimuli in experiments, and to evaluate the effects of word encoding order on perceived synonymy. (SW)

  5. Pairing, pseudogap and Fermi arcs in cuprates

    SciTech Connect

    Kaminski, Adam; Kondo, Takeshi; Takeuchi, Tsunehiro; Gu, Genda

    2014-04-29

    We use Angle Resolved Photoemission Spectroscopy (ARPES) to study the relationship between the pseudogap, pairing and Fermi arcs in cuprates. High quality data measured over a wide range of dopings reveals a consistent picture of Fermiology and pairing in these materials. The pseudogap is due to an ordered state that competes with superconductivity rather than preformed pairs. Pairing does occur below Tpair ~ 150K and significantly above Tc, but well below T* and the doping dependence of this temperature scale is distinct from that of the pseudogap. The d-wave gap is present below Tpair, and its interplay with strong scattering creates “artificial” Fermi arcs for Tc ≤ T ≤ Tpair. However, above Tpair, the pseudogap exists only at the antipodal region. This leads to presence of real, gapless Fermi arcs close to the node. The length of these arcs remains constant up to T*, where the full Fermi surface is recovered. As a result, we demonstrate that these findings resolve a number of seemingly contradictory scenarios.

  6. Spontaneous formation of inert oscillator pairs

    NASA Astrophysics Data System (ADS)

    Tsygankov, Denis; Wiesenfeld, Kurt

    2004-05-01

    We describe a peculiar type of spontaneous synchronization in a transmission line studded with nonlinear oscillators. After a transient period of complicated interactions, the elements form strongly synchronized pairs with interactions between these pairs virtually nil. The creation of these “dynamical dimers” appears to stem from the coupling intrinsic to transmission lines rather than any specific property of the nonlinear oscillators.

  7. Dressed electrostatic solitary excitations in three component pair-plasmas: Application in isothermal pair-plasma with stationary ions

    SciTech Connect

    Esfandyari-Kalejahi, A.; Akbari-Moghanjoughi, M.; Haddadpour-Khiaban, B.

    2009-10-15

    In this work electrostatic solitary waves in a three component pair-plasma consisting of hot isothermal electrons (or negative fullerene ions), positrons (or positive fullerene ions), and stationary positive ions (say, dust particulates) are studied. Using reductive perturbation method, plasma fluid equations are reduced to a Korteweg-de Vries (KdV) equation. Considering the higher-order nonlinearity, a linear inhomogeneous equation is derived, and the stationary solutions of these coupled equations are achieved by applying the renormalization procedure of Kodama-Taniuti. It is observed that in the linear approximation and applying Fourier analysis, two electrostatic modes, namely, upper or optical and lower or acoustic modes, are present. However, the application of reductive perturbation technique confirms that only acoustic-electrostatic mode can propagate in such plasma as KdV soliton, the amplitude and width of which are studied regarding to plasma parameters {sigma} (positron-to-electron temperature ratio) and {delta} (stationary cold ions-to-electron density ratio). It is also observed that the higher-order nonlinearity leads to deformation of the soliton structure from bell-shaped to W-shaped depending on the variation in values of the plasma parameters {sigma} and {delta}. It is revealed that KdV-type solitary waves cannot propagate in three component pair-plasma when the pair-species temperature is equal.

  8. Pairing in a dry Fermi sea.

    PubMed

    Maier, T A; Staar, P; Mishra, V; Chatterjee, U; Campuzano, J C; Scalapino, D J

    2016-01-01

    In the traditional Bardeen-Cooper-Schrieffer theory of superconductivity, the amplitude for the propagation of a pair of electrons with momentum k and -k has a log singularity as the temperature decreases. This so-called Cooper instability arises from the presence of an electron Fermi sea. It means that an attractive interaction, no matter how weak, will eventually lead to a pairing instability. However, in the pseudogap regime of the cuprate superconductors, where parts of the Fermi surface are destroyed, this log singularity is suppressed, raising the question of how pairing occurs in the absence of a Fermi sea. Here we report Hubbard model numerical results and the analysis of angular-resolved photoemission experiments on a cuprate superconductor. In contrast to the traditional theory, we find that in the pseudogap regime the pairing instability arises from an increase in the strength of the spin-fluctuation pairing interaction as the temperature decreases rather than the Cooper log instability. PMID:27312569

  9. Pairing in a dry Fermi sea

    NASA Astrophysics Data System (ADS)

    Maier, T. A.; Staar, P.; Mishra, V.; Chatterjee, U.; Campuzano, J. C.; Scalapino, D. J.

    2016-06-01

    In the traditional Bardeen-Cooper-Schrieffer theory of superconductivity, the amplitude for the propagation of a pair of electrons with momentum k and -k has a log singularity as the temperature decreases. This so-called Cooper instability arises from the presence of an electron Fermi sea. It means that an attractive interaction, no matter how weak, will eventually lead to a pairing instability. However, in the pseudogap regime of the cuprate superconductors, where parts of the Fermi surface are destroyed, this log singularity is suppressed, raising the question of how pairing occurs in the absence of a Fermi sea. Here we report Hubbard model numerical results and the analysis of angular-resolved photoemission experiments on a cuprate superconductor. In contrast to the traditional theory, we find that in the pseudogap regime the pairing instability arises from an increase in the strength of the spin-fluctuation pairing interaction as the temperature decreases rather than the Cooper log instability.

  10. Molecular organization of the complex between the muscarinic M3 receptor and the regulator of G protein signaling, Gbeta(5)-RGS7.

    PubMed

    Sandiford, Simone L; Wang, Qiang; Levay, Konstantin; Buchwald, Peter; Slepak, Vladlen Z

    2010-06-22

    The complex of the regulator of G protein signaling (RGS), Gbeta(5)-RGS7, can inhibit signal transduction via the M3 muscarinic acetylcholine receptor (M3R). RGS7 consists of three distinct structural entities: the DEP domain and its extension DHEX, the Ggamma-like (GGL) domain, which is permanently bound to Gbeta subunit Gbeta(5), and the RGS domain responsible for the interaction with Galpha subunits. Inhibition of the M3R by Gbeta(5)-RGS7 is independent of the RGS domain but requires binding of the DEP domain to the third intracellular loop of the receptor. Recent studies identified the dynamic intramolecular interaction between the Gbeta(5) and DEP domains, which suggested that the Gbeta(5)-RGS7 dimer could alternate between the "open" and "closed" conformations. Here, we identified point mutations that weaken DEP-Gbeta(5) binding, presumably stabilizing the open state, and tested their effects on the interaction of Gbeta(5)-RGS7 with the M3R. We found that these mutations facilitated binding of Gbeta(5)-RGS7 to the recombinant third intracellular loop of the M3R but did not enhance its ability to inhibit M3R-mediated Ca(2+) mobilization. This led us to the idea that the M3R can effectively induce the Gbeta(5)-RGS7 dimer to open; such a mechanism would require a region of the receptor distinct from the third loop. Indeed, we found that the C-terminus of M3R interacts with Gbeta(5)-RGS7. Truncation of the C-terminus rendered the M3R insensitive to inhibition by wild-type Gbeta(5)-RGS7; however, the open mutant of Gbeta(5)-RGS7 was able to inhibit signaling by the truncated M3R. The GST fusion of the M3R C-tail could not bind to wild-type Gbeta(5)-RGS7 but could associate with its open mutant as well as with the separated recombinant DEP domain or Gbeta(5). Taken together, our data are consistent with the following model: interaction of the M3R with Gbeta(5)-RGS7 causes the DEP domain and Gbeta(5) to dissociate from each other and bind to the C-tail, and the DEP

  11. Non-additivity of pair interactions in charged colloids.

    PubMed

    Finlayson, Samuel D; Bartlett, Paul

    2016-07-21

    It is general wisdom that the pair potential of charged colloids in a liquid may be closely approximated by a Yukawa interaction, as predicted by the classical Derjaguin-Landau-Verwey-Overbeek (DLVO) theory. We experimentally determine the effective forces in a binary mixture of like-charged particles, of species 1 and 2, with blinking optical tweezers. The measured forces are consistent with a Yukawa pair potential but the (12) cross-interaction is not equal to the geometric mean of the (11) and (22) like-interactions, as expected from DLVO. The deviation is a function of the electrostatic screening length and the size ratio, with the cross-interaction measured being consistently weaker than DLVO predictions. The corresponding non-additivity parameter is negative and grows in magnitude with increased size asymmetry. PMID:27448904

  12. Non-additivity of pair interactions in charged colloids

    NASA Astrophysics Data System (ADS)

    Finlayson, Samuel D.; Bartlett, Paul

    2016-07-01

    It is general wisdom that the pair potential of charged colloids in a liquid may be closely approximated by a Yukawa interaction, as predicted by the classical Derjaguin-Landau-Verwey-Overbeek (DLVO) theory. We experimentally determine the effective forces in a binary mixture of like-charged particles, of species 1 and 2, with blinking optical tweezers. The measured forces are consistent with a Yukawa pair potential but the (12) cross-interaction is not equal to the geometric mean of the (11) and (22) like-interactions, as expected from DLVO. The deviation is a function of the electrostatic screening length and the size ratio, with the cross-interaction measured being consistently weaker than DLVO predictions. The corresponding non-additivity parameter is negative and grows in magnitude with increased size asymmetry.

  13. Acoustic solitons in inhomogeneous pair-ion plasmas

    SciTech Connect

    Shah, Asif; Mahmood, S.; Haque, Q.

    2010-12-15

    The acoustic solitons are investigated in inhomogeneous unmagnetized pair ion plasmas. The Korteweg-de Vries (KdV) like equation with an additional term due to density gradients is deduced by employing reductive perturbation technique. It is noticed that pair-ion plasma system is conducive for the propagation of compressive as well as rarefactive solitons. The increase in the temperature ratio causes the amplitude of the rarefactive soliton to decrease. However, the amplitude of the compressive solitons is found to be increased as the temperature ratio of ions is enhanced. The amplitude of both compressive and rarefactive solitons is found to be increased as the density gradient parameter is increased. The equlibrium density profile is assumed to be exponential. The numerical results are shown for illustration.

  14. Optical Spectroscopy of Unbound Asteroid Pairs

    NASA Astrophysics Data System (ADS)

    Duddy, Samuel; Lowry, S. C.; Christou, A.; Wolters, S. D.; Snodgrass, C.; Fitzsimmons, A.; Deller, J. F.; Hainaut, O. R.; Rozitis, B.; Weissman, P. R.; Green, S. F.

    2012-10-01

    The recently discovered unbound asteroid pairs have been suggested to be the result of the decoupling of binary asteroids formed either through collision processes or, more likely, rotational fission of a rubble-pile asteroid after spin-up (Vokrouhlicky et al. 2008, AJ 136, 280; Pravec et al., 2010, Nature, 466, 1085). Much of the evidence for linkage of the asteroids in each pair relies solely on the backwards integrations of their orbits. We report new results from our continuing spectroscopic survey of the unbound asteroid pairs, including the youngest known pair, (6070) Rhineland - (54827) 2001 NQ8. The survey goal is to determine whether the asteroids in each unbound pair have similar spectra and therefore composition, expected if they have formed from a common parent body. Low-resolution spectroscopy covering the range 0.4-0.95 microns was conducted using the 3.6m ESO NTT+EFOSC2 during 2011-2012 and the 4.2m WHT+ACAM. We have attempted to maintain a high level of consistency between the observations of the components in each pair to ensure that differences in the asteroid spectra are not the result of the observing method or data reduction, but purely caused by compositional differences. Our WHT data indicates that the asteroids of unbound pair 17198 - 229056 exhibit different spectra and have been assigned different taxonomies, A and R respectively. Initial analysis of our data from the NTT suggests that the asteroids in unbound pairs 6070 - 54827 and 38707 - 32957 are likely silicate-dominated asteroids. The components of pair 23998 - 205383 are potentially X-type asteroids. We present final taxonomic classifications and the likelihood of spectral similarity in each pair.

  15. Stereo Pair: Wellington, New Zealand

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Wellington, the capital city of New Zealand, is located on the shores of Port Nicholson, a natural harbor at the south end of North Island. The city was founded in 1840 by British emigrants and now has a regional population of more than 400,000 residents. As seen here, the natural terrain imposes strong control over the urban growth pattern (urban features generally appear gray or white in this view). Rugged hills generally rising to 300 meters (1,000 feet) help protect the city and harbor from strong winter winds

    New Zealand is seismically active and faults are readily seen in the topography. The Wellington Fault forms the straight northwestern (left) shoreline of the harbor. Toward the southwest (down) the fault crosses through the city, then forms linear canyons in the hills before continuing offshore at the bottom. Toward the northeast (upper right) the fault forms the sharp mountain front along the northern edge of the heavily populated Hutt Valley.

    This stereoscopic image pair was generated using topographic data from the Shuttle Radar Topography Mission, combined with an enhanced true color Landsat7 satellite image. The topography data are used to create two differing perspectives of a single image, one perspective for each eye. In doing so, each point in the image is shifted slightly, depending on its elevation. When stereoscopically merged, the result is a vertically exaggerated view of the Earth's surface in its full three dimensions.

    Landsat satellites have provided visible light and infrared images of the Earth continuously since 1972. SRTM topographic data match the 30 meter (99 foot) spatial resolution of most Landsat images and will provide a valuable complement for studying the historic and growing Landsat data archive. The Landsat 7 Thematic Mapper image used here was provided to the SRTM project by the United States Geological Survey, Earth Resources Observation Systems (EROS) data Center, Sioux Falls, South Dakota.

    Elevation data

  16. SRTM Stereo Pair: Fiji Islands

    NASA Technical Reports Server (NTRS)

    2000-01-01

    image pair and viewing them with a stereoscope. When stereoscopically merged, the result is a vertically exaggerated view of the Earth's surface in its full three dimensions.

    This image was acquired by SRTM aboard the Space Shuttle Endeavour, launched on February 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (about 200 feet) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between the National Aeronautics and Space Administration (NASA), the National Imagery and Mapping Agency (NIMA) of the U.S. Department of Defense (DoD), and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Earth Science Enterprise, Washington, DC.

    Size: 192 km (119 miles) x 142 km (88 miles) Location: 17.8 deg. South lat., 178.0 deg. East lon. Orientation: North at top Date Acquired: February 19, 2000 Image: NASA/JPL/NIMA

  17. Electronic and structural properties of M3(HITP)2 (M = Ni, Cu and Co) metal-organic frameworks

    NASA Astrophysics Data System (ADS)

    Silveira, Orlando; Chacham, Helio; Alexandre, Simone

    Theoretical and experimental works have demonstrated that electrical and structural properties of metal-organic frameworks (MOF) can be significantly changed by the identity of the metal center, leading to a potential strategy for tuning the selectivity of the material toward different types of technological applications. In this work, we use first principle calculations to investigate the electronic properties of 2D MOF M3(HITP)2 (M is Ni, Cu and Co and HITP = 2,3,6,7,10,11 - hexaiminotriphenylene). Our results show that for M=Ni and Co, the structures are perfect planar and there is a full charge delocalization in the 2D plane of stacking due to the predominance of π - π bonding. The band structure for M = Ni shows that this material is a semiconductor with an indirect band gap of 132 meV, whilst for M = Co the band structure shows that this material is a ferromagnetic semiconductor with a direct band gap of 386 meV for spin down and a indirect band gap of 246 meV for spin up. For M=Cu, the material is a metal and adopts a distorted structure due to a different hybridization of the metal atom in comparison with its counterparts. We also propose a tight binding model that can represent the electronic structure near the Fermi level of this family of MOF.

  18. The photospheric magnetic field of the dM3.5e flare star AD Leonis

    NASA Technical Reports Server (NTRS)

    Saar, S. H.; Linsky, J. L.

    1985-01-01

    A high-resolution infrared spectrum of the dM3.5e flare star AD Leo, obtained with the Kitt Peak 4 m Fourier Transform Spectrometer, clearly shows the presence of strong magnetic fields. Five absorption lines in the 4400-4600 per cm region have been modeled, and it is inferred that 73 percent + or - 6 percent of the surface of AD Leo is covered by active regions outside of dark spots containing a mean field strength of 3800 + or - 260 G. If these active regions are brighter than the quiet photosphere, the surface filling factor will be somewhat smaller. Since simultaneous H-alpha observations exhibited no evidence of flares, the observations probably represent the quiescent magnetic flux level. The inferred field strength is consistent with equipartition of magnetic and thermal pressures in the photosphere and is similar to values derived using the scaling laws of Golub. The large observed filling factor is consistent with efficient dynamo generation of magnetic flux in this rapidly rotating star.

  19. Tests of shielding effectiveness of Kevlar and Nextel onboard the International Space Station and the Foton-M3 capsule.

    PubMed

    Pugliese, M; Bengin, V; Casolino, M; Roca, V; Zanini, A; Durante, M

    2010-08-01

    Radiation assessment and protection in space is the first step in planning future missions to the Moon and Mars, where mission and number of space travelers will increase and the protection of the geomagnetic shielding against the cosmic radiation will be absent. In this framework, the shielding effectiveness of two flexible materials, Kevlar and Nextel, were tested, which are largely used in the construction of spacecrafts. Accelerator-based tests clearly demonstrated that Kevlar is an excellent shield for heavy ions, close to polyethylene, whereas Nextel shows poor shielding characteristics. Measurements on flight performed onboard of the International Space Station and of the Foton-M3 capsule have been carried out with special attention to the neutron component; shielded and unshielded detectors (thermoluminescence dosemeters, bubble detectors) were exposed to a real radiation environment to test the shielding properties of the materials under study. The results indicate no significant effects of shielding, suggesting that thin shields in low-Earth Orbit have little effect on absorbed dose.

  20. Signalling pathway leading to an activation of mitogen-activated protein kinase by stimulating M3 muscarinic receptor.

    PubMed

    Kim, J Y; Yang, M S; Oh, C D; Kim, K T; Ha, M J; Kang, S S; Chun, J S

    1999-01-15

    The signalling pathway leading to an activation of mitogen-activated protein (MAP) kinase subtypes Erk-1 and -2 upon stimulation of muscarinic receptor with carbachol in human neuroblastoma SK-N-BE2(C) cells was investigated. Carbachol activated Erk-1/-2 by stimulating M3 muscarinic receptor, as determined by specific antagonists for individual muscarinic receptors. The activation of Erk-1/-2 by carbachol was blocked by the inhibition or down-regulation of protein kinase C (PKC). Among the multiple PKC isoforms expressed in SK-N-BE2(C) cells, only PKCepsilon was activated by the treatment of carbachol, and selective down-regulation of PKCepsilon was sufficient to block Erk-1/-2 activation. Carbachol treatment induced activation of the serine/threonine protein kinase Raf, and an inhibition of Raf blocked Erk-1/-2 activation. Ectopic expression of inhibitory small GTPase Ras, RasN17, blocked the carbachol-induced Raf activation without affecting the activation of PKCepsilon, while the inhibition of PKC blocked the Raf activation. Thus, these results suggest that carbachol-induced activation of PKCepsilon mediates Erk-1/-2 activation by a sequential activation of Ras, Raf and MAP kinase kinase.

  1. Full Stokes observations in the He i 1083 nm spectral region covering an M3.2 flare

    NASA Astrophysics Data System (ADS)

    Kuckein, Christoph; Collados, Manuel; Sainz, Rafael Manso; Ramos, Andrés Asensio

    2015-10-01

    We present an exceptional data set acquired with the Vacuum Tower Telescope (Tenerife, Spain) covering the pre-flare, flare, and post-flare stages of an M3.2 flare. The full Stokes spectropolarimetric observations were recorded with the Tenerife Infrared Polarimeter in the He i 1083.0 nm spectral region. The object under study was active region NOAA 11748 on 2013 May 17. During the flare the chomospheric He i 1083.0 nm intensity goes strongly into emission. However, the nearby photospheric Si i 1082.7 nm spectral line profile only gets shallower and stays in absorption. Linear polarization (Stokes Q and U) is detected in all lines of the He i triplet during the flare. Moreover, the circular polarization (Stokes V) is dominant during the flare, being the blue component of the He i triplet much stronger than the red component, and both are stronger than the Si i Stokes V profile. The Si i inversions reveal enormous changes of the photospheric magnetic field during the flare. Before the flare magnetic field concentrations of up to ~1500 G are inferred. During the flare the magnetic field strength globally decreases and in some cases it is even absent. After the flare the magnetic field recovers its strength and initial configuration.

  2. An intracellular redox sensor for reactive oxygen species at the M3-M4 linker of GABAAρ1 receptors

    PubMed Central

    Beltrán González, Andrea N; Gasulla, Javier; Calvo, Daniel J

    2014-01-01

    Background and Purpose Reactive oxygen species (ROS) are normally involved in cell oxidative stress but also play a role as cellular messengers in redox signalling; for example, modulating the activity of neurotransmitter receptors and ion channels. However, the direct actions of ROS on GABAA receptors were not previously demonstrated. In the present work, we studied the effects of ROS on GABAAρ1 receptor function. Experimental Approach GABAAρ1 receptors were expressed in oocytes and GABA-evoked responses electrophysiologically recorded in the presence or absence of ROS. Chemical protection of cysteines by selective sulfhydryl reagents and site-directed mutagenesis studies were used to identify protein residues involved in ROS actions. Key Results GABAAρ1 receptor-mediated responses were significantly enhanced in a concentration-dependent and reversible manner by H2O2. Potentiating effects were attenuated by a free radical scavenger, lipoic acid or an inhibitor of the Fenton reaction, deferoxamine. Each ρ1 subunit contains only three cysteine residues, two extracellular at the Cys-loop (C177 and C191) and one intracellular (C364) at the M3-M4 linker. Mutant GABAAρ1 receptors in which C364 was exchanged by alanine were completely insensitive to modulation, implying that this site, rather than a cysteine in the Cys-loop, is essential for ROS modulation. Conclusion and Implications Our results show that the function of GABAAρ1 receptors is enhanced by ROS and that the intracellular C364 is the sensor for ROS actions. PMID:24428763

  3. Acute effects of exposure to 1 mg/m(3) of vaporized 2-ethyl-1-hexanol in humans.

    PubMed

    Ernstgård, L; Norbäck, D; Nordquist, T; Wieslander, G; Wålinder, R; Johanson, G

    2010-04-01

    The objective was to assess acute effects from controlled exposure of volunteers to 2-ethyl-1-hexanol, a volatile organic compound that is often found in indoor air. Sixteen males and fourteen females were in random order exposed to 1 mg/m(3) of vapors of 2-ethyl-1-hexanol or to clean air (control exposure) in an exposure chamber during 2 h at rest. The subjects performed symptom ratings on Visual Analog Scales. During exposure to 2-ethyl-1-hexanol subjective ratings of smell and eye discomfort were minimally but significantly increased. Ratings of nasal irritation, throat irritation, headache, dyspnoea, fatigue, dizziness, nausea, and intoxication were not significantly affected. No exposure-related effects on measurement of blinking frequency by electromyography, measurement of the eye break-up time, vital staining of the eye, nasal lavage biomarkers, transfer tests, spirometric and rhinometric measures were seen. No differences in response were seen between sexes or between atopics and non-atopics. Practical Implications It is important to assess acute effects in volatile organic compounds like 2-ethyl-1-hexanol. 2-ethyl-1-hexanol is often found in indoor air generated by degradation of plastic building materials or in new buildings. There are associations between 2-ethyl-1-hexanol in indoor air and respiratory effects, eye irritation, headache, and blurred vision. A controlled chamber exposure study in acute effects was performed. In conclusion, this study showed weak subjective symptom of irritation in the eyes. PMID:20409194

  4. Mechanized welding of a Christmans tree of 06Kh20N8M3D2L steel

    SciTech Connect

    Leibzon, V.M.; kakhramanov, V.T.; Eshtokin, V.I.; Fataliev, S.O.; Fisher, V.O.; Pavlov, A.A.

    1986-03-01

    The most critical fitting of a well for the recovery of petroleum and gas with a high content of corrosive constituents is made of 06Kh20N8M3D2L steel. The quality, reliability, and life of a Christmas tree are determined primarily by the mechanical and corrosion properties of the weld joint. The authors report on the improvement of the existing method for welding the units of a Christmas tree. Argon and carbon dioxide were used as the protective medium in semiautomatic welding. The welding was done with a reverse polarity dc. An analysis of the data presented shows that the closest content to the base metal of chromium and nickel in the joint are provided in welding with OZL-41 electrodes. The molybdenum content in the joints welded with NZh-13 electrodes and Sv-08Kh19N10M38B wire in argon and carbon dioxide is at the level of the content of this element in the base metal.

  5. Tests of shielding effectiveness of Kevlar and Nextel onboard the International Space Station and the Foton-M3 capsule.

    PubMed

    Pugliese, M; Bengin, V; Casolino, M; Roca, V; Zanini, A; Durante, M

    2010-08-01

    Radiation assessment and protection in space is the first step in planning future missions to the Moon and Mars, where mission and number of space travelers will increase and the protection of the geomagnetic shielding against the cosmic radiation will be absent. In this framework, the shielding effectiveness of two flexible materials, Kevlar and Nextel, were tested, which are largely used in the construction of spacecrafts. Accelerator-based tests clearly demonstrated that Kevlar is an excellent shield for heavy ions, close to polyethylene, whereas Nextel shows poor shielding characteristics. Measurements on flight performed onboard of the International Space Station and of the Foton-M3 capsule have been carried out with special attention to the neutron component; shielded and unshielded detectors (thermoluminescence dosemeters, bubble detectors) were exposed to a real radiation environment to test the shielding properties of the materials under study. The results indicate no significant effects of shielding, suggesting that thin shields in low-Earth Orbit have little effect on absorbed dose. PMID:20364264

  6. DNA terminal base pairs have weaker hydrogen bonds especially for AT under low salt concentration

    NASA Astrophysics Data System (ADS)

    Ferreira, Izabela; Amarante, Tauanne D.; Weber, Gerald

    2015-11-01

    DNA base pairs are known to open more easily at the helix terminal, a process usually called end fraying, the details of which are still poorly understood. Here, we present a mesoscopic model calculation based on available experimental data where we consider separately the terminal base pairs of a DNA duplex. Our results show an important reduction of hydrogen bond strength for terminal cytosine-guanine (CG) base pairs which is uniform over the whole range of salt concentrations, while for AT base pairs, we obtain a nearly 1/3 reduction but only at low salt concentrations. At higher salt concentrations, terminal adenine-thymine (AT) pair has almost the same hydrogen bond strength than interior bases. The calculated terminal stacking interaction parameters display some peculiarly contrasting behavior. While there is mostly no perceptible difference to internal stacking, for some cases, we observe an unusually strong dependence with salt concentration which does not appear follow any pattern or trend.

  7. Optical emission of a molecular nanoantenna pair

    NASA Astrophysics Data System (ADS)

    Rice, E. M.; Andrews, D. L.

    2012-06-01

    The optical emission from a pair of nanoantennas is investigated within the theoretical framework of quantum electrodynamics. The analysis of fluorescent emission from a pair of molecular antenna species in close proximity is prompted by experimental work on oriented semiconductor polymer nanostructures. Each physically different possibility for separation-dependent features in photon emission by any such pair is explored in detail, leading to the identification of three distinct mechanisms: emission from a pair-delocalized exciton state, emission that engages electrodynamic coupling through quantum interference, and correlated photon emission from the two components of the pair. Although each mechanism produces a damped oscillatory dependence on the pair separation, each of the corresponding results exhibits an analytically different form. Significant differences in the associated spatial frequencies enable an apparent ambiguity in the interpretation of experiments to be resolved. Other major differences are found in the requisite conditions, the associated selection rules, and the variation with angular disposition of the emitters, together offering grounds for experimental discrimination between the coupling mechanisms. The analysis paves the way for investigations of pair-wise coupling effects in the emission from nanoantenna arrays.

  8. Partitioning of on-demand electron pairs

    NASA Astrophysics Data System (ADS)

    Ubbelohde, Niels; Hohls, Frank; Kashcheyevs, Vyacheslavs; Wagner, Timo; Fricke, Lukas; Kästner, Bernd; Pierz, Klaus; Schumacher, Hans W.; Haug, Rolf J.

    2015-01-01

    The on-demand generation and separation of entangled photon pairs are key components of quantum information processing in quantum optics. In an electronic analogue, the decomposition of electron pairs represents an essential building block for using the quantum state of ballistic electrons in electron quantum optics. The scattering of electrons has been used to probe the particle statistics of stochastic sources in Hanbury Brown and Twiss experiments and the recent advent of on-demand sources further offers the possibility to achieve indistinguishability between multiple sources in Hong-Ou-Mandel experiments. Cooper pairs impinging stochastically at a mesoscopic beamsplitter have been successfully partitioned, as verified by measuring the coincidence of arrival. Here, we demonstrate the splitting of electron pairs generated on demand. Coincidence correlation measurements allow the reconstruction of the full counting statistics, revealing regimes of statistically independent, distinguishable or correlated partitioning, and have been envisioned as a source of information on the quantum state of the electron pair. The high pair-splitting fidelity opens a path to future on-demand generation of spin-entangled electron pairs from a suitably prepared two-electron quantum-dot ground state.

  9. Colors of dynamically associated asteroid pairs

    NASA Astrophysics Data System (ADS)

    Moskovitz, Nicholas A.

    2012-09-01

    Recent dynamical studies have identified pairs of asteroids that reside in nearly identical heliocentric orbits. Possible formation scenarios for these systems include dissociation of binary asteroids, collisional disruption of a single parent body, or spin-up and rotational fission of a rubble-pile. Aside from detailed dynamical analyses and measurement of rotational light curves, little work has been done to investigate the colors or spectra of these unusual objects. A photometric and spectroscopic survey was conducted to determine the reflectance properties of asteroid pairs. New observations were obtained for a total of 34 individual asteroids. Additional photometric measurements were retrieved from the Sloan Digital Sky Survey Moving Object Catalog. Colors or spectra for a total of 42 pair components are presented here. The main findings of this work are: (1) the components in the observed pair systems have the same colors within the uncertainties of this survey, and (2) the color distribution of asteroid pairs appears indistinguishable from that of all Main Belt asteroids. These findings support a scenario of pair formation from a common progenitor and suggest that pair formation is likely a compositionally independent process. In agreement with previous studies, this is most consistent with an origin via binary disruption and/or rotational fission.

  10. A Curious Pair of Galaxies

    NASA Astrophysics Data System (ADS)

    2009-03-01

    The ESO Very Large Telescope has taken the best image ever of a strange and chaotic duo of interwoven galaxies. The images also contain some surprises -- interlopers both far and near. ESO PR Photo 11a/09 A Curious Pair of Galaxies ESO PR Video 11a/09 Arp 261 zoom in ESO PR Video 11b/09 Pan over Arp 261 Sometimes objects in the sky that appear strange, or different from normal, have a story to tell and prove scientifically very rewarding. This was the idea behind Halton Arp's catalogue of Peculiar Galaxies that appeared in the 1960s. One of the oddballs listed there is Arp 261, which has now been imaged in more detail than ever before using the FORS2 instrument on ESO's Very Large Telescope. The image proves to contain several surprises. Arp 261 lies about 70 million light-years distant in the constellation of Libra, the Scales. Its chaotic and very unusual structure is created by the interaction of two galaxies that are engaged in a slow motion, but highly disruptive close encounter. Although individual stars are very unlikely to collide in such an event, the huge clouds of gas and dust certainly do crash into each other at high speed, leading to the formation of bright new clusters of very hot stars that are clearly seen in the picture. The paths of the existing stars in the galaxies are also dramatically disrupted, creating the faint swirls extending to the upper left and lower right of the image. Both interacting galaxies were probably dwarfs not unlike the Magellanic Clouds orbiting our own galaxy. The images used to create this picture were not actually taken to study the interacting galaxies at all, but to investigate the properties of the inconspicuous object just to the right of the brightest part of Arp 261 and close to the centre of the image. This is an unusual exploding star, called SN 1995N, that is thought to be the result of the final collapse of a massive star at the end of its life, a so-called core collapse supernova. SN 1995N is unusual because

  11. Weird Stellar Pair Puzzles Scientists

    NASA Astrophysics Data System (ADS)

    2008-05-01

    Astronomers have discovered a speedy spinning pulsar in an elongated orbit around an apparent Sun-like star, a combination never seen before, and one that has them puzzled about how the strange system developed. Orbital Comparison Comparing Orbits of Pulsar and Its Companion to our Solar System. CREDIT: Bill Saxton, NRAO/AUI/NSF Click on image for full caption information and available graphics. "Our ideas about how the fastest-spinning pulsars are produced do not predict either the kind of orbit or the type of companion star this one has," said David Champion of the Australia Telescope National Facility. "We have to come up with some new scenarios to explain this weird pair," he added. Astronomers first detected the pulsar, called J1903+0327, as part of a long-term survey using the National Science Foundation's Arecibo radio telescope in Puerto Rico. They made the discovery in 2006 doing data analysis at McGill University, where Champion worked at the time. They followed up the discovery with detailed studies using the Arecibo telescope, the NSF's Robert C. Byrd Green Bank Telescope (GBT) in West Virginia, the Westerbork radio telescope in the Netherlands, and the Gemini North optical telescope in Hawaii. The pulsar, a city-sized superdense stellar corpse left over after a massive star exploded as a supernova, is spinning on its axis 465 times every second. Nearly 21,000 light-years from Earth, it is in a highly-elongated orbit that takes it around its companion star once every 95 days. An infrared image made with the Gemini North telescope in Hawaii shows a Sun-like star at the pulsar's position. If this is an orbital companion to the pulsar, it is unlike any companions of other rapidly rotating pulsars. The pulsar, a neutron star, also is unusually massive for its type. "This combination of properties is unprecedented. Not only does it require us to figure out how this system was produced, but the large mass may help us understand how matter behaves at extremely

  12. On limits of ab initio calculations of pairing gap in nuclei

    SciTech Connect

    Saperstein, E. E.; Baldo, M.; Lombardo, U.; Pankratov, S. S.; Zverev, M. V.

    2011-11-15

    A brief review of recent microscopic calculations of nuclear pairing gap is given. A semi-microscopic model is suggested in which the ab initio effective pairing interaction is supplemented with a small phenomenological addendum. It involves a parameter which is universal for all medium and heavy nuclei. Calculations for several isotopic and isotonic chains of semi-magic nuclei confirm the relevance of the model.

  13. Multiband superconductivity with competing intra- and interband pair channels

    NASA Astrophysics Data System (ADS)

    Kristoffel, N.; Rubin, P.

    2016-03-01

    In multiband superconductivity interband interaction channels creating the pairs of intraband (Wa) and interband (Wb) compositions can appear. Simultaneous functioning of these channels is investigated here. A three-band model where two similar bands (a; b) interact with the itinerant-band has been proposed. The mean field Hamiltonian incorporates three order parameters Δa; Δad; Δb1,2 genetically associated with dispersive bands. Calculated quasiparticle energies and operator averages lead to a coupled nonlinear equation system for the order parameters. Illustrative calculations versus temperature have been made for overlapping bands. At fixed parameters, the basic system has two independent solutions. The free energy has a complicated structure of extremal points. The interaction of channels with intra- and interband points is seen. These channels compete in general. From the point where the gap, type parameters associated with one channel become zero, the other continues as the first channel was logged out. The general behaviour of order parameters distribution is very sensible to Wb. Events of critical nature appear. Weakening of Wb stimulates the formation of closed bubbles built up by the same type parameters from different parallel solutions.

  14. Three Pairs of New Isopentenyl Dibenzo[b,e]oxepinone Enantiomers from Talaromyces flavus, a Wetland Soil-Derived Fungus.

    PubMed

    Sun, Tian-Yu; Kuang, Run-Qiao; Chen, Guo-Dong; Qin, Sheng-Ying; Wang, Chuan-Xi; Hu, Dan; Wu, Bing; Liu, Xing-Zhong; Yao, Xin-Sheng; Gao, Hao

    2016-01-01

    Three pairs of new isopentenyl dibenzo[b,e]oxepinone enantiomers, (+)-(5S)-arugosin K (1a), (-)-(5R)-arugosin K (1b), (+)-(5S)-arugosin L (2a), (-)-(5R)-arugosin L (2b), (+)-(5S)-arugosin M (3a), (-)-(5R)-arugosin M (3b), and a new isopentenyl dibenzo[b,e]oxepinone, arugosin N (4), were isolated from a wetland soil-derived fungus Talaromyces flavus, along with two known biosynthetically-related compounds 5 and 6. Among them, arugosin N (4) and 1,6,10-trihydroxy-8-methyl-2-(3-methyl-2-butenyl)-dibenz[b,e]oxepin-11(6H)-one (CAS: 160585-91-1, 5) were obtained as the tautomeric mixtures. The structures of isolated compounds were determined by detailed spectroscopic analysis. In addition, the absolute configurations of these three pairs of new enantiomers were determined by quantum chemical ECD calculations. PMID:27617983

  15. Structure and Function of the Snail Statocyst System after Orbital Missions on Foton M-2 and M-3

    NASA Astrophysics Data System (ADS)

    Balaban, P. M.; Malyshev, A. Y.; Ierusalimsky, V. N.; Aseev, N. A.; Korshunova, T. A.; Bravarenko, N. I.; Lemak, M. S.; Roschin, M. V.; Zakharov, I. S.; Popova, Y.; Boyle, R.

    2008-06-01

    In terrestrial gastropod snail Helix lucorum L. we studied the changes after a 16-day (Foton M-2) and 12-day (Foton M-3) exposure to microgravity in: behavior, neural responses to adequate motion stimulation, intersensory interactions between the photo- and the statocyst receptors, and in expression of the HPeP and FMRFa genes in the statoreceptors. Experiments were performed in the interval 13-30 hours after landing. In behavioral experiments it was found that the latency of body position response to sudden orientation change (90° pitch head-down from horizontal position) was significantly reduced in the postflight snails. Responses recorded extracellularly from the statocyst nerve to adequate motion stimulation in the postflight snails were independent of the motion direction, while in the control animals differences in responses to different directions were observed. In electrophysiological recordings it was possible to distinguish firing patterns of up to 11 of the 13 receptors that constitute the statocyst. A significantly higher firing rate in statocyst responses to body orientation at all tested speeds were observed in postflight snails, while in control snails similar dependence of statocyst responses on speed of body position change was observed, but firing rate at each speed was significantly less. Significant differences in the HPeP gene mRNA expression pattern in the statocyst receptor neurons were observed between postflight and control snails. No differences in expression of FMRFa gene expression was noted in the nervous system or statocyst after the flight. Results suggest a possibility to describe the subcellular mechanisms of changes in gravireceptors due to microgravity exposure using this simple model animal.

  16. Draft Genome Sequence of the Bacteriocin-Producing Strain Enterococcus faecium M3K31, Isolated from Griffon Vultures (Gyps fulvus subsp. fulvus).

    PubMed

    Arbulu, Sara; Frantzen, Cyril; Lohans, Christopher T; Cintas, Luis M; Herranz, Carmen; Holo, Helge; Diep, Dzung B; Vederas, John C; Hernández, Pablo E

    2016-03-24

    Enterococcus faeciumM3K31 is a bacteriocinogenic lactic acid bacterium (LAB) isolated from griffon vulture (Gyps fulvussubsp.fulvus) feces. The draft genome sequence of this strain provides genetic data that support its biotechnological potential.

  17. Real-time fluid dynamics investigation and physiological response for erythromycin fermentation scale-up from 50 L to 132 m3 fermenter.

    PubMed

    Zou, Xiang; Xia, Jian-ye; Chu, Ju; Zhuang, Ying-ping; Zhang, Si-liang

    2012-06-01

    The physiological response of erythromycin fermentation scale-up from 50 L to 132 m(3) scale was investigated. A relatively high oxygen uptake rate (OUR) in early phase of fermentation was beneficial for erythromycin biosynthesis. Correspondingly, the maximal consistency coefficient (K) reflecting non-Newtonian fluid characteristics in 50 L and 132 m(3) fermenter also appeared in same phase. Fluid dynamics in different scale bioreactor was further investigated by real-time computational fluid dynamics modeling. The results of simulation showed that the impeller combination in 50 L fermenter could provide more modest flow field environment compared with that in 132 m(3) fermenter. The decrease of oxygen transfer rate (OTR) in 132 m(3) fermenter was the main cause for impairing cell physiological metabolism and erythromycin biosynthesis. These results were helpful for understanding the relationship between hydrodynamic environment and physiological response of cells in bioreactor during the scale-up of fermentation process. PMID:22139481

  18. Draft Genome Sequence of the Bacteriocin-Producing Strain Enterococcus faecium M3K31, Isolated from Griffon Vultures (Gyps fulvus subsp. fulvus)

    PubMed Central

    Arbulu, Sara; Frantzen, Cyril; Lohans, Christopher T.; Cintas, Luis M.; Herranz, Carmen; Holo, Helge; Diep, Dzung B.; Vederas, John C.

    2016-01-01

    Enterococcus faecium M3K31 is a bacteriocinogenic lactic acid bacterium (LAB) isolated from griffon vulture (Gyps fulvus subsp. fulvus) feces. The draft genome sequence of this strain provides genetic data that support its biotechnological potential. PMID:27013035

  19. Draft Genome Sequence of the Bacteriocin-Producing Strain Enterococcus faecium M3K31, Isolated from Griffon Vultures (Gyps fulvus subsp. fulvus).

    PubMed

    Arbulu, Sara; Frantzen, Cyril; Lohans, Christopher T; Cintas, Luis M; Herranz, Carmen; Holo, Helge; Diep, Dzung B; Vederas, John C; Hernández, Pablo E

    2016-01-01

    Enterococcus faeciumM3K31 is a bacteriocinogenic lactic acid bacterium (LAB) isolated from griffon vulture (Gyps fulvussubsp.fulvus) feces. The draft genome sequence of this strain provides genetic data that support its biotechnological potential. PMID:27013035

  20. Richardson-Gaudin description of pairing in atomic nuclei

    NASA Astrophysics Data System (ADS)

    De Baerdemacker, Stijn

    2012-05-01

    The present contribution discusses a connection between the exact Bethe Ansatz eigenstates of the reduced Bardeen-Cooper-Schrieffer (BCS) Hamiltonian and the multi-phonon states of the Tamm-Dancoff Approximation (TDA). The connection is made on the algebraic level, by means of a deformed quasi-spin algebra with a bosonic Heisenberg-Weyl algebra in the contraction limit of the deformation parameter. Each exact Bethe Ansatz eigenstate is mapped on a unique TDA multi-phonon state, shedding light on the physics behind the Bethe Ansatz structure of the exact wave function. The procedure is illustrated with a model describing neutron pairing in 56Fe.

  1. Unique Footprint in the scl1.3 Locus Affects Adhesion and Biofilm Formation of the Invasive M3-Type Group A Streptococcus

    PubMed Central

    Bachert, Beth A.; Choi, Soo J.; LaSala, Paul R.; Harper, Tiffany I.; McNitt, Dudley H.; Boehm, Dylan T.; Caswell, Clayton C.; Ciborowski, Pawel; Keene, Douglas R.; Flores, Anthony R.; Musser, James M.; Squeglia, Flavia; Marasco, Daniela; Berisio, Rita; Lukomski, Slawomir

    2016-01-01

    The streptococcal collagen-like proteins 1 and 2 (Scl1 and Scl2) are major surface adhesins that are ubiquitous among group A Streptococcus (GAS). Invasive M3-type strains, however, have evolved two unique conserved features in the scl1 locus: (i) an IS1548 element insertion in the scl1 promoter region and (ii) a nonsense mutation within the scl1 coding sequence. The scl1 transcript is drastically reduced in M3-type GAS, contrasting with a high transcription level of scl1 allele in invasive M1-type GAS. This leads to a lack of Scl1 expression in M3 strains. In contrast, while scl2 transcription and Scl2 production are elevated in M3 strains, M1 GAS lack Scl2 surface expression. M3-type strains were shown to have reduced biofilm formation on inanimate surfaces coated with cellular fibronectin and laminin, and in human skin equivalents. Repair of the nonsense mutation and restoration of Scl1 expression on M3-GAS cells, restores biofilm formation on cellular fibronectin and laminin coatings. Inactivation of scl1 in biofilm-capable M28 and M41 strains results in larger skin lesions in a mouse model, indicating that lack of Scl1 adhesin promotes bacterial spread over localized infection. These studies suggest the uniquely evolved scl1 locus in the M3-type strains, which prevents surface expression of the major Scl1 adhesin, contributed to the emergence of the invasive M3-type strains. Furthermore these studies provide insight into the molecular mechanisms mediating colonization, biofilm formation, and pathogenesis of group A streptococci. PMID:27630827

  2. Unique Footprint in the scl1.3 Locus Affects Adhesion and Biofilm Formation of the Invasive M3-Type Group A Streptococcus.

    PubMed

    Bachert, Beth A; Choi, Soo J; LaSala, Paul R; Harper, Tiffany I; McNitt, Dudley H; Boehm, Dylan T; Caswell, Clayton C; Ciborowski, Pawel; Keene, Douglas R; Flores, Anthony R; Musser, James M; Squeglia, Flavia; Marasco, Daniela; Berisio, Rita; Lukomski, Slawomir

    2016-01-01

    The streptococcal collagen-like proteins 1 and 2 (Scl1 and Scl2) are major surface adhesins that are ubiquitous among group A Streptococcus (GAS). Invasive M3-type strains, however, have evolved two unique conserved features in the scl1 locus: (i) an IS1548 element insertion in the scl1 promoter region and (ii) a nonsense mutation within the scl1 coding sequence. The scl1 transcript is drastically reduced in M3-type GAS, contrasting with a high transcription level of scl1 allele in invasive M1-type GAS. This leads to a lack of Scl1 expression in M3 strains. In contrast, while scl2 transcription and Scl2 production are elevated in M3 strains, M1 GAS lack Scl2 surface expression. M3-type strains were shown to have reduced biofilm formation on inanimate surfaces coated with cellular fibronectin and laminin, and in human skin equivalents. Repair of the nonsense mutation and restoration of Scl1 expression on M3-GAS cells, restores biofilm formation on cellular fibronectin and laminin coatings. Inactivation of scl1 in biofilm-capable M28 and M41 strains results in larger skin lesions in a mouse model, indicating that lack of Scl1 adhesin promotes bacterial spread over localized infection. These studies suggest the uniquely evolved scl1 locus in the M3-type strains, which prevents surface expression of the major Scl1 adhesin, contributed to the emergence of the invasive M3-type strains. Furthermore these studies provide insight into the molecular mechanisms mediating colonization, biofilm formation, and pathogenesis of group A streptococci. PMID:27630827

  3. σ-Aromatic cyclic M3(+) (M = Cu, Ag, Au) clusters and their complexation with dimethyl imidazol-2-ylidene, pyridine, isoxazole, furan, noble gases and carbon monoxide.

    PubMed

    Pan, Sudip; Saha, Ranajit; Mandal, Subhajit; Chattaraj, Pratim K

    2016-04-28

    The σ-aromaticity of M3(+) (M = Cu, Ag, Au) is analyzed and compared with that of Li3(+) and a prototype σ-aromatic system, H3(+). Ligands (L) like dimethyl imidazol-2-ylidene, pyridine, isoxazole and furan are employed to stabilize these monocationic M3(+) clusters. They all bind M3(+) with favorable interaction energy. Dimethyl imidazol-2-ylidene forms the strongest bond with M3(+) followed by pyridine, isoxazole and furan. Electrostatic contribution is considerably more than that of orbital contribution in these M-L bonds. The orbital interaction arises from both L → M σ donation and L ← M back donation. M3(+) clusters also bind noble gas atoms and carbon monoxide effectively. In general, among the studied systems Au3(+) binds a given L most strongly followed by Cu3(+) and Ag3(+). Computation of the nucleus-independent chemical shift (NICS) and its different extensions like the NICS-rate and NICS in-plane component vs. NICS out-of-plane component shows that the σ-aromaticity in L bound M3(+) increases compared to that of bare clusters. The aromaticity in pyridine, isoxazole and furan bound Au3(+) complexes is quite comparable with that in the recently synthesized Zn3(C5(CH3)5)3(+). The energy gap between the highest occupied molecular orbital and the lowest unoccupied molecular orbital also increases upon binding with L. The blue-shift and red-shift in the C-O stretching frequency of M3(CO)3(+) and M3(OC)3(+), respectively, are analyzed through reverse polarization of the σ- and π-orbitals of CO as well as the relative amount of OC → M σ donation and M → CO π back donation. The electron density analysis is also performed to gain further insight into the nature of interaction. PMID:26624276

  4. Natural Disruption of Two Regulatory Networks in Serotype M3 Group A Streptococcus Isolates Contributes to the Virulence Factor Profile of This Hypervirulent Serotype

    PubMed Central

    Cao, Tram N.; Liu, Zhuyun; Cao, Tran H.; Pflughoeft, Kathryn J.; Treviño, Jeanette; Danger, Jessica L.; Beres, Stephen B.; Musser, James M.

    2014-01-01

    Despite the public health challenges associated with the emergence of new pathogenic bacterial strains and/or serotypes, there is a dearth of information regarding the molecular mechanisms that drive this variation. Here, we began to address the mechanisms behind serotype-specific variation between serotype M1 and M3 strains of the human pathogen Streptococcus pyogenes (the group A Streptococcus [GAS]). Spatially diverse contemporary clinical serotype M3 isolates were discovered to contain identical inactivating mutations within genes encoding two regulatory systems that control the expression of important virulence factors, including the thrombolytic agent streptokinase, the protease inhibitor-binding protein-G-related α2-macroglobulin-binding (GRAB) protein, and the antiphagocytic hyaluronic acid capsule. Subsequent analysis of a larger collection of isolates determined that M3 GAS, since at least the 1920s, has harbored a 4-bp deletion in the fasC gene of the fasBCAX regulatory system and an inactivating polymorphism in the rivR regulator-encoding gene. The fasC and rivR mutations in M3 isolates directly affect the virulence factor profile of M3 GAS, as evident by a reduction in streptokinase expression and an enhancement of GRAB expression. Complementation of the fasC mutation in M3 GAS significantly enhanced levels of the small regulatory RNA FasX, which in turn enhanced streptokinase expression. Complementation of the rivR mutation in M3 GAS restored the regulation of grab mRNA abundance but did not alter capsule mRNA levels. While important, the fasC and rivR mutations do not provide a full explanation for why serotype M3 strains are associated with unusually severe invasive infections; thus, further investigation is warranted. PMID:24516115

  5. Unique Footprint in the scl1.3 Locus Affects Adhesion and Biofilm Formation of the Invasive M3-Type Group A Streptococcus

    PubMed Central

    Bachert, Beth A.; Choi, Soo J.; LaSala, Paul R.; Harper, Tiffany I.; McNitt, Dudley H.; Boehm, Dylan T.; Caswell, Clayton C.; Ciborowski, Pawel; Keene, Douglas R.; Flores, Anthony R.; Musser, James M.; Squeglia, Flavia; Marasco, Daniela; Berisio, Rita; Lukomski, Slawomir

    2016-01-01

    The streptococcal collagen-like proteins 1 and 2 (Scl1 and Scl2) are major surface adhesins that are ubiquitous among group A Streptococcus (GAS). Invasive M3-type strains, however, have evolved two unique conserved features in the scl1 locus: (i) an IS1548 element insertion in the scl1 promoter region and (ii) a nonsense mutation within the scl1 coding sequence. The scl1 transcript is drastically reduced in M3-type GAS, contrasting with a high transcription level of scl1 allele in invasive M1-type GAS. This leads to a lack of Scl1 expression in M3 strains. In contrast, while scl2 transcription and Scl2 production are elevated in M3 strains, M1 GAS lack Scl2 surface expression. M3-type strains were shown to have reduced biofilm formation on inanimate surfaces coated with cellular fibronectin and laminin, and in human skin equivalents. Repair of the nonsense mutation and restoration of Scl1 expression on M3-GAS cells, restores biofilm formation on cellular fibronectin and laminin coatings. Inactivation of scl1 in biofilm-capable M28 and M41 strains results in larger skin lesions in a mouse model, indicating that lack of Scl1 adhesin promotes bacterial spread over localized infection. These studies suggest the uniquely evolved scl1 locus in the M3-type strains, which prevents surface expression of the major Scl1 adhesin, contributed to the emergence of the invasive M3-type strains. Furthermore these studies provide insight into the molecular mechanisms mediating colonization, biofilm formation, and pathogenesis of group A streptococci.

  6. Specificity of g protein-coupled receptor kinase 6-mediated phosphorylation and regulation of single-cell m3 muscarinic acetylcholine receptor signaling.

    PubMed

    Willets, Jonathon M; Mistry, Rajendra; Nahorski, Stefan R; Challiss, R A John

    2003-11-01

    Previously we have shown that G protein-coupled receptor kinase (GRK) 6 plays a major role in the regulation of the human M3 muscarinic acetylcholine receptor (M3 mAChR) in the human neuroblastoma SH-SY5Y. However, 30-fold overexpression of the catalytically inactive, dominant-negative K215RGRK6 produced only a 50% suppression of M3 mAChR phosphorylation and desensitization. Here, we have attempted to determine whether other endogenous kinases play a role in the regulation of M3 mAChR signaling. In contrast to the clear attenuating effect of K215RGRK6 expression on M3 mAChR regulation, dominant-negative forms of GRKs (K220RGRK2, K220RGRK3, K215RGRK5) and casein kinase 1alpha (K46RCK1alpha) were without effect. In addition, inhibition of a variety of second-messenger-regulated kinases and the tyrosine kinase Src also had no effect upon agonist-stimulated M3 mAChR regulation. To investigate further the desensitization process we have followed changes in inositol 1,4,5-trisphosphate in single SHSY5Y cells using the pleckstrin homology domain of PLCdelta1 tagged with green fluorescent protein (eGFP-PHPLCdelta1). Stimulation of cells with approximate EC50 concentrations of agonist before and after a desensitizing period of agonist exposure resulted in a marked attenuation of the latter response. Altered GRK6 activity, through overexpression of wild-type GRK6 or K215RGRK6, enhanced or reduced the degree of M3 mAChR desensitization, respectively. Taken together, our data indicate that M3 mAChR desensitization is mediated by GRK6 in human SH-SY5Y cells, and we show that receptor desensitization of phospholipase C signaling can be monitored in 'real-time' in single, living cells. PMID:14573754

  7. 90 Seconds of Discovery: Frustrated Lewis Pairs

    SciTech Connect

    Kathmann, Shawn; Schenter, Greg; Autrey, Tom

    2014-02-14

    Hydrogen activating catalysts play an important role in producing valuable chemicals, such as biofuels and ammonia. As a part of efforts to develop the next generation of these catalysts, PNNL researchers have found potential in Frustrated Lewis Pairs.

  8. Engineering a factorable photon pair source

    SciTech Connect

    Zielnicki, Kevin; Kwiat, Paul

    2014-12-04

    Spontaneous parametric downconversion is an important process for producing pairs of photons for quantum optics. We discuss a scheme for eliminating undesired inter-photon correlations inherent in this process, and an efficient characterization of spectral correlations.

  9. Pair-production in inhomogeneous electric fields

    SciTech Connect

    Xue Shesheng

    2008-01-03

    This is a preliminary study on the rate of electron-positron pair production in spatially inhomogeneous electric fields. We study the rate in the Sauter field and compare it to the rate in the homogeneous field.

  10. Alloy solution hardening with solute pairs

    DOEpatents

    Mitchell, John W.

    1976-08-24

    Solution hardened alloys are formed by using at least two solutes which form associated solute pairs in the solvent metal lattice. Copper containing equal atomic percentages of aluminum and palladium is an example.

  11. Non stationary pair model in blazar

    NASA Astrophysics Data System (ADS)

    Marcowith, Alexandre; Henri, Gilles; Renaud, Nicolas

    2001-09-01

    This article shortly present an improved version of pair models for X and gamma-ray emission from blazar jets. The radiations are generated through external and synchrotron Inverse Compton mechanisms in the vicinity of a super-massive black hole by an ultra-relativistic electron-positron pair plasma pervading a non-relativistic electron-proton jet (two-flow model). Non stationary solutions are found by solving simultaneously pair creation/annihilation, soft photon absorption and particle acceleration processes along the jet. The power supply necessary to re-accelerate particles is not treated in a self-consistent procedure but parametrised. Pair creation opacity effects can lead to interesting variability effects depending on the X-ray emission regimes. Multi-wavelength observations by INTEGRAL will provide tests for the model, and also for the matter content and variability mechanisms in compact sources.

  12. 90 Seconds of Discovery: Frustrated Lewis Pairs

    ScienceCinema

    Kathmann, Shawn; Schenter, Greg; Autrey, Tom

    2016-07-12

    Hydrogen activating catalysts play an important role in producing valuable chemicals, such as biofuels and ammonia. As a part of efforts to develop the next generation of these catalysts, PNNL researchers have found potential in Frustrated Lewis Pairs.

  13. Mixed parity pairing in a dipolar gas

    NASA Astrophysics Data System (ADS)

    Bruun, G. M.; Hainzl, C.; Laux, M.

    2016-10-01

    We show that fermionic dipoles in a two-layer geometry form Cooper pairs with both singlet and triplet components when they are tilted with respect to the normal of the planes. The mixed parity pairing arises because the interaction between dipoles in the two different layers is not inversion symmetric. We use an efficient eigenvalue approach to calculate the zero-temperature phase diagram of the system as a function of the dipole orientation and the layer distance. The phase diagram contains purely triplet as well as mixed singlet and triplet superfluid phases. We show in detail how the pair wave function for dipoles residing in different layers smoothly changes from singlet to triplet symmetry as the orientation of the dipoles is changed. Our results indicate that dipolar quantum gases can be used to unambiguously observe mixed parity pairing.

  14. Ultrabright source of entangled photon pairs.

    PubMed

    Dousse, Adrien; Suffczyński, Jan; Beveratos, Alexios; Krebs, Olivier; Lemaître, Aristide; Sagnes, Isabelle; Bloch, Jacqueline; Voisin, Paul; Senellart, Pascale

    2010-07-01

    A source of triggered entangled photon pairs is a key component in quantum information science; it is needed to implement functions such as linear quantum computation, entanglement swapping and quantum teleportation. Generation of polarization entangled photon pairs can be obtained through parametric conversion in nonlinear optical media or by making use of the radiative decay of two electron-hole pairs trapped in a semiconductor quantum dot. Today, these sources operate at a very low rate, below 0.01 photon pairs per excitation pulse, which strongly limits their applications. For systems based on parametric conversion, this low rate is intrinsically due to the Poissonian statistics of the source. Conversely, a quantum dot can emit a single pair of entangled photons with a probability near unity but suffers from a naturally very low extraction efficiency. Here we show that this drawback can be overcome by coupling an optical cavity in the form of a 'photonic molecule' to a single quantum dot. Two coupled identical pillars-the photonic molecule-were etched in a semiconductor planar microcavity, using an optical lithography method that ensures a deterministic coupling to the biexciton and exciton energy states of a pre-selected quantum dot. The Purcell effect ensures that most entangled photon pairs are emitted into two cavity modes, while improving the indistinguishability of the two optical recombination paths. A polarization entangled photon pair rate of 0.12 per excitation pulse (with a concurrence of 0.34) is collected in the first lens. Our results open the way towards the fabrication of solid state triggered sources of entangled photon pairs, with an overall (creation and collection) efficiency of 80%. PMID:20613838

  15. Extracting differential pair distribution functions using MIXSCAT

    SciTech Connect

    Wurden, Caroline; Page, Katharine; Llobet, Anna; White, Claire E.; Proffen, Thomas

    2010-08-27

    Differently weighted experimental scattering data have been used to extract partial or differential structure factors or pair distribution functions in studying many materials. However, this is not done routinely partly because of the lack of user-friendly software. This paper presents MIXSCAT, a new member of the DISCUS program package. MIXSCAT allows one to combine neutron and X-ray pair distribution functions and extract their respective differential functions.

  16. The insect repellent N,N-diethyl-m-toluamide (DEET) induces angiogenesis via allosteric modulation of the M3 muscarinic receptor in endothelial cells.

    PubMed

    Legeay, Samuel; Clere, Nicolas; Hilairet, Grégory; Do, Quoc-Tuan; Bernard, Philippe; Quignard, Jean-François; Apaire-Marchais, Véronique; Lapied, Bruno; Faure, Sébastien

    2016-01-01

    The insect repellent N,N-diethyl-m-toluamide (DEET) has been reported to inhibit AChE (acetylcholinesterase) and to possess potential carcinogenic properties with excessive vascularization. In the present paper, we demonstrate that DEET specifically stimulates endothelial cells that promote angiogenesis which increases tumor growth. DEET activates cellular processes that lead to angiogenesis including proliferation, migration and adhesion. This is associated with an enhancement of NO production and VEGF expression in endothelial cells. M3 silencing or the use of a pharmacological M3 inhibitor abrogates all of these effects which reveals that DEET-induced angiogenesis is M3 sensitive. The experiments involving calcium signals in both endothelial and HEK cells overexpressing M3 receptors, as well as binding and docking studies demonstrate that DEET acts as an allosteric modulator of the M3 receptor. In addition, DEET inhibited AChE which increased acetylcholine bioavailability and binding to M3 receptors and also strengthened proangiogenic effects by an allosteric modulation. PMID:27345502

  17. The insect repellent N,N-diethyl-m-toluamide (DEET) induces angiogenesis via allosteric modulation of the M3 muscarinic receptor in endothelial cells

    PubMed Central

    Legeay, Samuel; Clere, Nicolas; Hilairet, Grégory; Do, Quoc-Tuan; Bernard, Philippe; Quignard, Jean-François; Apaire-Marchais, Véronique; Lapied, Bruno; Faure, Sébastien

    2016-01-01

    The insect repellent N,N-diethyl-m-toluamide (DEET) has been reported to inhibit AChE (acetylcholinesterase) and to possess potential carcinogenic properties with excessive vascularization. In the present paper, we demonstrate that DEET specifically stimulates endothelial cells that promote angiogenesis which increases tumor growth. DEET activates cellular processes that lead to angiogenesis including proliferation, migration and adhesion. This is associated with an enhancement of NO production and VEGF expression in endothelial cells. M3 silencing or the use of a pharmacological M3 inhibitor abrogates all of these effects which reveals that DEET-induced angiogenesis is M3 sensitive. The experiments involving calcium signals in both endothelial and HEK cells overexpressing M3 receptors, as well as binding and docking studies demonstrate that DEET acts as an allosteric modulator of the M3 receptor. In addition, DEET inhibited AChE which increased acetylcholine bioavailability and binding to M3 receptors and also strengthened proangiogenic effects by an allosteric modulation. PMID:27345502

  18. Glass-forming ability and rigidity percolation in SeTePb lone-pair semiconductors

    NASA Astrophysics Data System (ADS)

    Sharma, Pankaj

    2016-04-01

    Correlating the various physical parameters of known semiconductors and pointing the properties of new ones, a number of parameters have been employed recently with different levels of success. Taking this into account an attempt has been made to correlate the physical properties of Pb-doped Se-Te lone-pair semiconductors. The small band gap and large Bohr radius of lead (Pb) containing lone-pair semiconductors assist them with specific optical, electrical and thermal properties. The various physical parameters like number of constraints, lone pair of electron, heat of atomization, density, compactness, free volume percentage have been analyzed in terms of mean coordination number for (Se90Te10)100- x Pb x (x = 0, 4, 8, 12, 16, 20, 24). The band gap for the compositions has been determined theoretically, and the obtained results are very well explained in terms of cohesive energy, electronegativity and average single bond energy.

  19. Non-Watson-Crick base pairing in RNA. quantum chemical analysis of the cis Watson-Crick/sugar edge base pair family.

    PubMed

    Sponer, Judit E; Spacková, Nad'a; Kulhanek, Petr; Leszczynski, Jerzy; Sponer, Jirí

    2005-03-17

    Large RNA molecules exhibit an astonishing variability of base-pairing patterns, while many of the RNA base-pairing families have no counterparts in DNA. The cis Watson-Crick/sugar edge (cis WC/SE) RNA base pairing is investigated by ab initio quantum chemical calculations. A detailed structural and energetic characterization of all 13 crystallographically detected members of this family is provided by means of B3LYP/6-31G and RIMP2/aug-cc-pVDZ calculations. Further, a prediction is made for the remaining 3 cis WC/SE base pairs which are yet to be seen in the experiments. The interaction energy calculations point at the key role of the 2'-OH group in stabilizing the sugar-base contact and predict all 16 cis WC/SE base-pairing patterns to be nearly isoenergetic. The perfect correlation of the main geometrical parameters in the gas-phase optimized and X-ray structures shows that the principle of isosteric substitutions in RNA is rooted from the intrinsic structural similarity of the isolated base pairs. The present quantum chemical calculations for the first time analyze base pairs involving the ribose 2'-OH group and unambiguously correlate the structural information known from experiments with the energetics of interactions. The calculations further show that the relative importance and absolute value of the dispersion energy in the cis WC/SE base pairs are enhanced compared to the standard base pairs. This may by an important factor contributing to the strength of such interactions when RNA folds in its polar environment. The calculations further demonstrate that the Cornell et al. force field commonly used in molecular modeling and simulations provides satisfactory performance for this type of RNA interactions. PMID:16838999

  20. Recognition of Short Time-Paired Activities

    NASA Astrophysics Data System (ADS)

    Chaminda, Hapugahage Thilak; Klyuev, Vitaly; Naruse, Keitaro; Osano, Minetada

    We undertake numerous activities in our daily life and for some of those we forget to complete the action as originally intended. Significant aspects while performing most of these actions might be: “pairing of both hands simultaneously” and “short time consumption”. In this work an attempt has been made to recognize those kinds of Paired Activities (PAs), which are easy to forget, and to provide a method to remind about uncompleted PAs. To represent PAs, a study was done on opening and closing of various bottles. A model to define PAs, which simulated the paired behavior of both hands, is proposed, called “Paired Activity Model” (PAM). To recognize PAs using PAM, Paired Activity Recognition Algorithm (PARA) was implemented. Paired motion capturing was done by accelerometers, which were worn by subjects on the wrist areas of both hands. Individual and correlative behavior of both hands was used to recognize exact PA among other activities. Artificial Neural Network (ANN) algorithm was used for data categorization in PARA. ANN significantly outperformed the support vector machine algorithm in real time evaluations. In the user-independent case, PARA achieved recognition rates of 96% for only target PAs and 91% for target PAs undertaken amidst unrelated activities.

  1. Migration of helium-pair in metals

    NASA Astrophysics Data System (ADS)

    Cao, J. L.; Geng, W. T.

    2016-09-01

    We have carried out a first-principles density functional theory investigation into the migration of both a single interstitial He and an interstitial He-pair in Fe, Mo, W, Cu, Pd, and Pt. We find the migration trajectories and barriers are determined predominantly by low-energy He-pair configurations which depend mainly on the energy state of a single He in different interstices. The migration barrier for a He-pair in bcc metals is always slightly higher than for a single He. Configurations of a He-pair in fcc metals are very complicated, due to the existence of interstitial sites with nearly identical energy for a single He. The migration barrier for a He-pair is slightly lower than (in Cu), or similar to (in Pd and Pt) a single He. The collective migrations of a He-pair are ensured by strong Hesbnd He interactions with strength-versus-distance forms resembling chemical bonds and can be described with Morse potentials.

  2. Formation of asteroid pairs by rotational fission.

    PubMed

    Pravec, P; Vokrouhlický, D; Polishook, D; Scheeres, D J; Harris, A W; Galád, A; Vaduvescu, O; Pozo, F; Barr, A; Longa, P; Vachier, F; Colas, F; Pray, D P; Pollock, J; Reichart, D; Ivarsen, K; Haislip, J; Lacluyze, A; Kusnirák, P; Henych, T; Marchis, F; Macomber, B; Jacobson, S A; Krugly, Yu N; Sergeev, A V; Leroy, A

    2010-08-26

    Pairs of asteroids sharing similar heliocentric orbits, but not bound together, were found recently. Backward integrations of their orbits indicated that they separated gently with low relative velocities, but did not provide additional insight into their formation mechanism. A previously hypothesized rotational fission process may explain their formation-critical predictions are that the mass ratios are less than about 0.2 and, as the mass ratio approaches this upper limit, the spin period of the larger body becomes long. Here we report photometric observations of a sample of asteroid pairs, revealing that the primaries of pairs with mass ratios much less than 0.2 rotate rapidly, near their critical fission frequency. As the mass ratio approaches 0.2, the primary period grows long. This occurs as the total energy of the system approaches zero, requiring the asteroid pair to extract an increasing fraction of energy from the primary's spin in order to escape. We do not find asteroid pairs with mass ratios larger than 0.2. Rotationally fissioned systems beyond this limit have insufficient energy to disrupt. We conclude that asteroid pairs are formed by the rotational fission of a parent asteroid into a proto-binary system, which subsequently disrupts under its own internal system dynamics soon after formation.

  3. Seniority zero pair coupled cluster doubles theory

    SciTech Connect

    Stein, Tamar; Henderson, Thomas M.; Scuseria, Gustavo E.

    2014-06-07

    Coupled cluster theory with single and double excitations accurately describes weak electron correlation but is known to fail in cases of strong static correlation. Fascinatingly, however, pair coupled cluster doubles (p-CCD), a simplified version of the theory limited to pair excitations that preserve the seniority of the reference determinant (i.e., the number of unpaired electrons), has mean field computational cost and is an excellent approximation to the full configuration interaction (FCI) of the paired space provided that the orbital basis defining the pairing scheme is adequately optimized. In previous work, we have shown that optimization of the pairing scheme in the seniority zero FCI leads to a very accurate description of static correlation. The same conclusion extends to p-CCD if the orbitals are optimized to make the p-CCD energy stationary. We here demonstrate these results with numerous examples. We also explore the contributions of different seniority sectors to the coupled cluster doubles (CCD) correlation energy using different orbital bases. We consider both Hartree-Fock and Brueckner orbitals, and the role of orbital localization. We show how one can pair the orbitals so that the role of the Brueckner orbitals at the CCD level is retained at the p-CCD level. Moreover, we explore ways of extending CCD to accurately describe strongly correlated systems.

  4. Spectral similarity of unbound asteroid pairs

    NASA Astrophysics Data System (ADS)

    Wolters, Stephen D.; Weissman, Paul R.; Christou, Apostolis; Duddy, Samuel R.; Lowry, Stephen C.

    2014-04-01

    Infrared (IR) spectroscopy between 0.8 and 2.5 μ has been obtained for both components of three unbound asteroid pairs, using the NASA Infrared Telescope Facility with the SpeX instrument. Pair primary (2110) Moore-Sitterly is classified as an S-type following the Bus-DeMeo taxonomy; the classification for secondary (44612) 1999 RP27 is ambiguous: S/Sq/Q/K/L-type. Primary (10484) Hecht and secondary (44645) 1999 RC118 are classified as V-types. IR spectra for Moore-Sitterly and Hecht are each linked with available visual photometry. The classifications for primary (88604) 2001 QH293 and (60546) 2000 EE85 are ambiguous: S/Sq/Q/K/L-type. Subtle spectral differences between them suggest that the primary may have more weathered material on its surface. Dynamical integrations have constrained the ages of formation: 2110-44612 > 782 kyr; 10484-44645 = 348 (+823,-225) kyr; 88604-60546 = 925 (+842,-754) kyr. The spectral similarity of seven complete pairs is ranked in comparison with nearby background asteroids. Two pairs, 17198-229056 and 19289-278067, have significantly different spectra between the components, compared to the similarity of spectra in the background population. The other pairs are closer than typical, supporting an interpretation of each pair's formation from a common parent body.

  5. Fundamental aspects of recoupled pair bonds. I. Recoupled pair bonds in carbon and sulfur monofluoride

    SciTech Connect

    Dunning, Thom H. Xu, Lu T.; Takeshita, Tyler Y.

    2015-01-21

    The number of singly occupied orbitals in the ground-state atomic configuration of an element defines its nominal valence. For carbon and sulfur, with two singly occupied orbitals in their {sup 3}P ground states, the nominal valence is two. However, in both cases, it is possible to form more bonds than indicated by the nominal valence—up to four bonds for carbon and six bonds for sulfur. In carbon, the electrons in the 2s lone pair can participate in bonding, and in sulfur the electrons in both the 3p and 3s lone pairs can participate. Carbon 2s and sulfur 3p recoupled pair bonds are the basis for the tetravalence of carbon and sulfur, and 3s recoupled pair bonds enable sulfur to be hexavalent. In this paper, we report generalized valence bond as well as more accurate calculations on the a{sup 4}Σ{sup −} states of CF and SF, which are archetypal examples of molecules that possess recoupled pair bonds. These calculations provide insights into the fundamental nature of recoupled pair bonds and illustrate the key differences between recoupled pair bonds formed with the 2s lone pair of carbon, as a representative of the early p-block elements, and recoupled pair bonds formed with the 3p lone pair of sulfur, as a representative of the late p-block elements.

  6. A Model for the Vortex Pair Associated with a Jet in a Cross Flow

    NASA Technical Reports Server (NTRS)

    Sellers, William L.

    1975-01-01

    A model is presented for the contrarotating vortex pair that is formed by a round, turbulent, subsonic jet directed normally into a uniform, subsonic cross flow. The model consists of a set of algebraic equations that describe the properties of the vortex pair as a function of their location in the jet plume. The parameters of the model are physical characteristics of the vortices such as the vortex strength, spacing, and core size. These parameters are determined by velocity measurements at selective points in the jet plume.

  7. Pair correlation functions of FeAs-based superconductors: Quantum Monte Carlo study

    NASA Astrophysics Data System (ADS)

    Kashurnikov, V. A.; Krasavin, A. V.

    2015-01-01

    The new generalized quantum continuous time world line Monte Carlo algorithm was developed to calculate pair correlation functions for two-dimensional FeAs-clusters modeling of iron-based superconductors within the framework of the two-orbital model. The analysis of pair correlations depending on the cluster size, temperature, interaction, and the type of symmetry of the order parameter is carried out. The data obtained for clusters with sizes up to 1 0x1 0 FeAs-cells favor the possibility of an effective charge carrier's attraction that is corresponding the A1g-symmetry, at some parameters of interaction.

  8. The M3 Phosphorylation Site Is Required for Trafficking and Biological Roles of PIN-FORMED1, 2, and 7 in Arabidopsis

    PubMed Central

    Ki, Daeeun; Sasayama, Daisuke; Cho, Hyung-Taeg

    2016-01-01

    Asymmetrically localized PIN-FORMED (PIN) auxin efflux carriers play key roles in regulating directional intercellular auxin movement, generating local auxin gradients, and diverse auxin-mediated growth and development. The polar localization of PINs is controlled by phosphorylation in the central hydrophilic loop (HL) of PINs. Although the M3 phosphorylation site, including phosphorylatable 5 Ser/Thr residues, is conserved among long HL-PINs, its native role has only been characterized in PIN3. In this study, we examined the role of M3 phosphorylation site of PIN1, PIN2, and PIN7 in intracellular trafficking, phosphorylation, and biological functions of those PINs in their native expressing tissues. Phosphorylation-defective mutations of the phosphorylatable residues in the M3 site of PIN1-HL led to alteration in subcellular polarity of PIN1 and caused defects in PIN1-mediated biological functions such as cotyledon development, phyllotaxy of vegetative leaves, and development of reproductive organs. The M3 mutations of PIN7 interfered with its polar recycling in the root columella cell in response to gravity stimulus and partially disrupted root gravitropism. On the other hand, the M3 site of PIN2 was shown to be necessary for its targeting to the plasma membrane. In vitro phosphorylation assay showed that the M3 phosphorylation residues of PIN1 are the partial targets by PINOID kinase. Our data suggest that the M3 phosphorylation site is functionally conserved among long HL-PINs by playing roles for their subcellular trafficking and auxin-mediated developmental processes. PMID:27733863

  9. Functional selectivity of muscarinic receptor antagonists for inhibition of M3-mediated phosphoinositide responses in guinea pig urinary bladder and submandibular salivary gland.

    PubMed

    Nelson, Carl P; Gupta, Paul; Napier, Carolyn M; Nahorski, Stefan R; Challiss, R A John

    2004-09-01

    Binding and functional affinities of the muscarinic acetylcholine (mACh) receptor antagonists darifenacin, tolterodine, oxybutynin, and atropine were assessed in Chinese hamster ovary (CHO) cells expressing the human recombinant M2 (CHO-m2) or M3 (CHO-m3) receptors, and in guinea pig bladder and submandibular gland. In [N-methyl-3H]scopolamine methyl chloride binding studies in CHO cells, darifenacin displayed selectivity (14.8-fold) for the M3 versus M2 mACh receptor subtype. Oxybutynin was nonselective, whereas atropine and tolterodine were weakly M2-selective (5.1- and 6.6-fold, respectively). Antagonist functional affinity estimates were determined by the inhibition of agonist-induced [3H]inositol phosphate accumulation in CHO-m3 cells and antagonism of the agonist-induced inhibition of forskolin-stimulated cyclic AMP accumulation in CHO-m2 cells. Darifenacin was the most M3-selective antagonist (32.4-fold), whereas oxybutynin, atropine, and tolterodine exhibited lesser selectivity. Functional affinity estimates in guinea pig urinary bladder and submandibular salivary gland using indices of phosphoinositide turnover revealed that oxybutynin, darifenacin, and tolterodine each displayed selectivity for the response in the bladder, relative to that seen in the submandibular gland (9.3-, 7.9-, and 7.4-fold, respectively). In contrast, atropine displayed a similar affinity in both tissues. These data demonstrate that in bladder, compared with submandibular gland from a single species, the mACh receptor antagonists darifenacin, tolterodine, and oxybutynin display selectivity to inhibit agonist-mediated phosphoinositide responses. It is proposed that both responses are mediated via M3 mACh receptor activation and that differential functional affinities displayed by some, but not all, antagonists are indicative of the influence of cell background upon the pharmacology of the M3 mACh receptor. PMID:15140916

  10. Experimental extraction of an entangled photon pair from two identically decohered pairs.

    PubMed

    Yamamoto, Takashi; Koashi, Masato; Ozdemir, Sahin Kaya; Imoto, Nobuyuki

    2003-01-23

    Entanglement is considered to be one of the most important resources in quantum information processing schemes, including teleportation, dense coding and entanglement-based quantum key distribution. Because entanglement cannot be generated by classical communication between distant parties, distribution of entangled particles between them is necessary. During the distribution process, entanglement between the particles is degraded by the decoherence and dissipation processes that result from unavoidable coupling with the environment. Entanglement distillation and concentration schemes are therefore needed to extract pairs with a higher degree of entanglement from these less-entangled pairs; this is accomplished using local operations and classical communication. Here we report an experimental demonstration of extraction of a polarization-entangled photon pair from two decohered photon pairs. Two polarization-entangled photon pairs are generated by spontaneous parametric down-conversion and then distributed through a channel that induces identical phase fluctuations to both pairs; this ensures that no entanglement is available as long as each pair is manipulated individually. Then, through collective local operations and classical communication we extract from the two decohered pairs a photon pair that is observed to be polarization-entangled.

  11. High base pair opening rates in tracts of GC base pairs.

    PubMed

    Dornberger, U; Leijon, M; Fritzsche, H

    1999-03-12

    Sequence-dependent structural features of the DNA double helix have a strong influence on the base pair opening dynamics. Here we report a detailed study of the kinetics of base pair breathing in tracts of GC base pairs in DNA duplexes derived from 1H NMR measurements of the imino proton exchange rates upon titration with the exchange catalyst ammonia. In the limit of infinite exchange catalyst concentration, the exchange times of the guanine imino protons of the GC tracts extrapolate to much shorter base pair lifetimes than commonly observed for isolated GC base pairs. The base pair lifetimes in the GC tracts are below 5 ms for almost all of the base pairs. The unusually rapid base pair opening dynamics of GC tracts are in striking contrast to the behavior of AT tracts, where very long base pair lifetimes are observed. The implication of these findings for the structural principles governing spontaneous helix opening as well as the DNA-binding specificity of the cytosine-5-methyltransferases, where flipping of the cytosine base has been observed, are discussed.

  12. Pairing instabilities of Dirac composite fermions

    NASA Astrophysics Data System (ADS)

    Milovanović, M. V.; Ćirić, M. Dimitrijević; Juričić, V.

    2016-09-01

    Recently, a Dirac (particle-hole symmetric) description of composite fermions in the half-filled Landau level (LL) was proposed [D. T. Son, Phys. Rev. X 5, 031027 (2015), 10.1103/PhysRevX.5.031027], and we study its possible consequences on BCS (Cooper) pairing of composite fermions (CFs). One of the main consequences is the existence of anisotropic states in single-layer and bilayer systems, which was previously suggested in Jeong and Park [J. S. Jeong and K. Park, Phys. Rev. B 91, 195119 (2015), 10.1103/PhysRevB.91.195119]. We argue that in the half-filled LL in the single-layer case the gapped states may sustain anisotropy, because isotropic pairings may coexist with anisotropic ones. Furthermore, anisotropic pairings with the addition of a particle-hole symmetry-breaking mass term may evolve into rotationally symmetric states, i.e., Pfaffian states of Halperin-Lee-Read (HLR) ordinary CFs. On the basis of the Dirac formalism, we argue that in the quantum Hall bilayer at total filling factor 1, with decreasing distance between the layers, weak pairing of p -wave paired CFs is gradually transformed from Dirac to ordinary, HLR-like, with a concomitant decrease in the CF number. Global characterization of low-energy spectra based on the Dirac CFs agrees well with previous calculations performed by exact diagonalization on a torus. Finally, we discuss features of the Dirac formalism when applied in this context.

  13. Parity Protection in Flux-Pairing Qubits

    NASA Astrophysics Data System (ADS)

    Zhang, Wenyuan; Bell, Matthew; Jin, Xiaoyue; Ioffe, Lev; Gershenson, Michael

    2015-03-01

    We have studied a novel qubit whose logical states are decoupled from the environment due to parity protection. The flux-pairing qubit (FPQ) is a superconducting loop consisting of a 4 π periodic Josephson element (a Cooper pair box with the e charge on the central island) and a superinductor. This device is dual to the charge-pairing qubit. The FPQ design suppresses tunneling of single flux lines through the junctions in the Cooper pair box and enforces simultaneous tunneling of pairs of flux lines. The lowest-energy quantum states of the FPQ are encoded in the parity of the magnetic flux quanta inside the loop. Parity protection prohibits the mixing of these states, and reduces both the decay and dephasing rates. We will discuss the experimental aspects of the FPQ optimization and the possibility of fault-tolerant operations with these qubits. The work was supported in part by grants from the Templeton Foundation (40381) and the NSF (DMR-1006265).

  14. Radical-pair based avian magnetoreception

    NASA Astrophysics Data System (ADS)

    Procopio, Maria; Ritz, Thorsten

    2014-03-01

    Behavioural experiments suggest that migratory birds possess a magnetic compass sensor able to detect the direction of the geomagnetic. One hypothesis for the basis of this remarkable sensory ability is that the coherent quantum spin dynamics of photoinduced radical pair reactions transduces directional magnetic information from the geomagnetic field into changes of reaction yields, possibly involving the photoreceptor cryptochrome in the birds retina. The suggested radical-pair based avian magnetoreception has attracted attention in the field of quantum biology as an example of a biological sensor which might exploit quantum coherences for its biological function. Investigations on such a spin-based sensor have focussed on uncovering the design features for the design of a biomimetic magnetic field sensor. We study the effects of slow fluctuations in the nuclear spin environment on the directional signal. We quantitatively evaluate the robustness of signals under fluctuations on a timescale longer than the lifetime of a radical pair, utilizing two models of radical pairs. Our results suggest design principles for building a radical-pair based compass sensor that is both robust and highly directional sensitive.

  15. On the analysis of phylogenetically paired designs

    PubMed Central

    Funk, Jennifer L; Rakovski, Cyril S; Macpherson, J Michael

    2015-01-01

    As phylogenetically controlled experimental designs become increasingly common in ecology, the need arises for a standardized statistical treatment of these datasets. Phylogenetically paired designs circumvent the need for resolved phylogenies and have been used to compare species groups, particularly in the areas of invasion biology and adaptation. Despite the widespread use of this approach, the statistical analysis of paired designs has not been critically evaluated. We propose a mixed model approach that includes random effects for pair and species. These random effects introduce a “two-layer” compound symmetry variance structure that captures both the correlations between observations on related species within a pair as well as the correlations between the repeated measurements within species. We conducted a simulation study to assess the effect of model misspecification on Type I and II error rates. We also provide an illustrative example with data containing taxonomically similar species and several outcome variables of interest. We found that a mixed model with species and pair as random effects performed better in these phylogenetically explicit simulations than two commonly used reference models (no or single random effect) by optimizing Type I error rates and power. The proposed mixed model produces acceptable Type I and II error rates despite the absence of a phylogenetic tree. This design can be generalized to a variety of datasets to analyze repeated measurements in clusters of related subjects/species. PMID:25750719

  16. Pairing and specific heat in hot nuclei

    NASA Astrophysics Data System (ADS)

    Gambacurta, Danilo; Lacroix, Denis; Sandulescu, N.

    2013-09-01

    The thermodynamics of pairing phase-transition in nuclei is studied in the canonical ensemble and treating the pairing correlations in a finite-temperature variation after projection BCS approach (FT-VAP). Due to the restoration of particle number conservation, the pairing gap and the specific heat calculated in the FT-VAP approach vary smoothly with the temperature, indicating a gradual transition from the superfluid to the normal phase, as expected in finite systems. We have checked that the predictions of the FT-VAP approach are very accurate when compared to the results obtained by an exact diagonalization of the pairing Hamiltonian. The influence of pairing correlations on specific heat is analyzed for the isotopes 161,162Dy and 171,172Yb. It is shown that the FT-VAP approach, applied with a level density provided by mean field calculations and supplemented, at high energies, by the level density of the back-shifted Fermi gas model, can approximate reasonably well the main properties of specific heat extracted from experimental data. However, the detailed shape of the calculated specific heat is rather sensitive to the assumption made for the mean field.

  17. Pairing in a dry Fermi sea

    DOE PAGES

    Maier, Thomas A.; Staar, Peter; Mishra, V.; Chatterjee, Utpal; Campuzano, J. C.; Scalapino, Douglas J.

    2016-06-17

    In the traditional Bardeen–Cooper–Schrieffer theory of superconductivity, the amplitude for the propagation of a pair of electrons with momentum k and -k has a log singularity as the temperature decreases. This so-called Cooper instability arises from the presence of an electron Fermi sea. It means that an attractive interaction, no matter how weak, will eventually lead to a pairing instability. However, in the pseudogap regime of the cuprate superconductors, where parts of the Fermi surface are destroyed, this log singularity is suppressed, raising the question of how pairing occurs in the absence of a Fermi sea. In this paper, wemore » report Hubbard model numerical results and the analysis of angular-resolved photoemission experiments on a cuprate superconductor. Finally, in contrast to the traditional theory, we find that in the pseudogap regime the pairing instability arises from an increase in the strength of the spin–fluctuation pairing interaction as the temperature decreases rather than the Cooper log instability.« less

  18. Pairing in a dry Fermi sea

    PubMed Central

    Maier, T. A; Staar, P.; Mishra, V.; Chatterjee, U.; Campuzano, J. C.; Scalapino, D. J.

    2016-01-01

    In the traditional Bardeen–Cooper–Schrieffer theory of superconductivity, the amplitude for the propagation of a pair of electrons with momentum k and −k has a log singularity as the temperature decreases. This so-called Cooper instability arises from the presence of an electron Fermi sea. It means that an attractive interaction, no matter how weak, will eventually lead to a pairing instability. However, in the pseudogap regime of the cuprate superconductors, where parts of the Fermi surface are destroyed, this log singularity is suppressed, raising the question of how pairing occurs in the absence of a Fermi sea. Here we report Hubbard model numerical results and the analysis of angular-resolved photoemission experiments on a cuprate superconductor. In contrast to the traditional theory, we find that in the pseudogap regime the pairing instability arises from an increase in the strength of the spin–fluctuation pairing interaction as the temperature decreases rather than the Cooper log instability. PMID:27312569

  19. Theoretical analysis of novel fiber grating pair

    NASA Astrophysics Data System (ADS)

    Wang, Liao; Jia, Hongzhi; Fang, Liang; You, Bei

    2016-06-01

    A novel fiber grating pair that consists of a conventional long-period fiber grating and a fiber Bragg cladding grating (FBCG) is proposed. The FBCG is a new type of fiber grating in which refractive index modulation is formed in the cladding. Through the coupled-mode theory, we accurately calculate the coupling coefficients between modes supported in the fibers. And some other mode coupling features in the fiber cladding gratings are analyzed in detail. The calculation of the modes involved in this paper is based on a model of three-layer step-index fiber geometry. Then, we have investigated the sensitivity characteristics for variation of the modulation strengths of the fiber Bragg cladding gratings' resonance peaks and the long-period cladding gratings' (LPCGs) dual resonant peaks. Finally, the modulation strength sensitivity of the grating pair's three resonant peaks is demonstrated, and the results indicate that these grating pairs may find potential applications in optical fiber sensing.

  20. Automated DNA Base Pair Calling Algorithm

    1999-07-07

    The procedure solves the problem of calling the DNA base pair sequence from two channel electropherogram separations in an automated fashion. The core of the program involves a peak picking algorithm based upon first, second, and third derivative spectra for each electropherogram channel, signal levels as a function of time, peak spacing, base pair signal to noise sequence patterns, frequency vs ratio of the two channel histograms, and confidence levels generated during the run. Themore » ratios of the two channels at peak centers can be used to accurately and reproducibly determine the base pair sequence. A further enhancement is a novel Gaussian deconvolution used to determine the peak heights used in generating the ratio.« less

  1. An Evolved Orthogonal Enzyme/Cofactor Pair.

    PubMed

    Reynolds, Evan W; McHenry, Matthew W; Cannac, Fabien; Gober, Joshua G; Snow, Christopher D; Brustad, Eric M

    2016-09-28

    We introduce a strategy that expands the functionality of hemoproteins through orthogonal enzyme/heme pairs. By exploiting the ability of a natural heme transport protein, ChuA, to promiscuously import heme derivatives, we have evolved a cytochrome P450 (P450BM3) that selectively incorporates a nonproteinogenic cofactor, iron deuteroporphyrin IX (Fe-DPIX), even in the presence of endogenous heme. Crystal structures show that selectivity gains are due to mutations that introduce steric clash with the heme vinyl groups while providing a complementary binding surface for the smaller Fe-DPIX cofactor. Furthermore, the evolved orthogonal enzyme/cofactor pair is active in non-natural carbenoid-mediated olefin cyclopropanation. This methodology for the generation of orthogonal enzyme/cofactor pairs promises to expand cofactor diversity in artificial metalloenzymes.

  2. Hard Photodisintegration of a Proton Pair

    DOE PAGES

    Pomerantz, Ishay; Bubis, Nathaniel; Allada, Kalyan; Beck, Arie; Beck, Sara; Berman, Barry L.; Boeglin, Werner U.; Camsonne, Alexandre; Canan, Mustafa; Chirapatpimol, Khem; et al

    2010-01-08

    We present the first study of high energy photodisintegration of proton-pairs through the gamma + 3He -> p+p+n channel. Photon energies from 0.8 to 4.7 GeV were used in kinematics corresponding to a proton pair with high relative momentum and a neutron nearly at rest. An s^{-11} scaling of the cross section was observed, as predicted by the constituent counting rule. The onset of the scaling is at a higher energy and the cross section is significantly lower then for pn pair photodisintegration. For photon energies below the scaling region, the scaled cross section was found to present a strongmore » energy-dependent structure not observed in deuteron photodisintegration.« less

  3. Parametric Amplification of Scattered Atom Pairs

    SciTech Connect

    Campbell, Gretchen K.; Mun, Jongchul; Boyd, Micah; Streed, Erik W.; Ketterle, Wolfgang; Pritchard, David E.

    2006-01-20

    We have observed parametric generation and amplification of ultracold atom pairs. A {sup 87}Rb Bose-Einstein condensate was loaded into a one-dimensional optical lattice with quasimomentum k{sub 0} and spontaneously scattered into two final states with quasimomenta k{sub 1} and k{sub 2}. Furthermore, when a seed of atoms was first created with quasimomentum k{sub 1} we observed parametric amplification of scattered atoms pairs in states k{sub 1} and k{sub 2} when the phase-matching condition was fulfilled. This process is analogous to optical parametric generation and amplification of photons and could be used to efficiently create entangled pairs of atoms. Furthermore, these results explain the dynamic instability of condensates in moving lattices observed in recent experiments.

  4. Hadronic production of massive lepton pairs

    SciTech Connect

    Berger, E.L.

    1982-12-01

    A review is presented of recent experimental and theoretical progress in studies of the production of massive lepton pairs in hadronic collisions. I begin with the classical Drell-Yan annihilation model and its predictions. Subsequently, I discuss deviations from scaling, the status of the proofs of factorization in the parton model, higher-order terms in the perturbative QCD expansion, the discrepancy between measured and predicted yields (K factor), high-twist terms, soft gluon effects, transverse-momentum distributions, implications for weak vector boson (W/sup + -/ and Z/sup 0/) yields and production properties, nuclear A dependence effects, correlations of the lepton pair with hadrons in the final state, and angular distributions in the lepton-pair rest frame.

  5. Calculation of the Transition from Pairing Vibrational to Pairing Rotational Regimes between Magic Nuclei {sup 100}Sn and {sup 132}Sn via Two-Nucleon Transfer Reactions

    SciTech Connect

    Potel, G.; Barranco, F.; Marini, F.; Idini, A.; Vigezzi, E.; Broglia, R. A.

    2011-08-26

    Absolute values of two-particle transfer cross sections along the Sn-isotopic chain are calculated. They agree with measurements within errors and without free parameters. Within this scenario, the predictions concerning the absolute value of the two-particle transfer cross sections associated with the excitation of the pairing vibrational spectrum expected around the recently discovered closed shell nucleus {sub 50}{sup 132}Sn{sub 82} and the very exotic nucleus {sub 50}{sup 100}Sn{sub 50} can be considered quantitative, opening new perspectives in the study of pairing in nuclei.

  6. Photon pair generation in birefringent optical fibers

    NASA Astrophysics Data System (ADS)

    Smith, Brian J.; Mahou, P.; Cohen, Offir; Lundeen, J. S.; Walmsley, I. A.

    2009-12-01

    We study both experimentally and theoretically the generation of photon pairs by spontaneous four-wave mixing (SFWM) in standard birefringent optical fibers. The ability to produce a range of two-photon spectral states, from highly correlated (entangled) to completely factorable, by means of cross-polarized birefringent phase matching, is explored. A simple model is developed to predict the spectral state of the photon pair which shows how this can be adjusted by choosing the appropriate pump bandwidth, fiber length and birefringence. Spontaneous Raman scattering is modeled to determine the tradeoff between SFWM and background Raman noise, and the predicted results are shown to agree with experimental data.

  7. Comment on ``Pairing interaction and Galilei invariance''

    NASA Astrophysics Data System (ADS)

    Arias, J. M.; Gallardo, M.; Gómez-Camacho, J.

    1999-05-01

    A recent article by Dussel, Sofia, and Tonina studies the relation between Galilei invariance and dipole energy weighted sum rule (EWSR). The authors find that the pairing interaction, which is neither Galilei nor Lorentz invariant, produces big changes in the EWSR and in effective masses of the nucleons. They argue that these effects of the pairing force could be realistic. In this Comment we stress the validity of Galilei invariance to a very good approximation in this context of low-energy nuclear physics and show that the effective masses and the observed change in the EWSR for the electric dipole operator relative to its classical value are compatible with this symmetry.

  8. M3B2 and M5B3 Formation in Diffusion-Affected Zone During Transient Liquid Phase Bonding Single-Crystal Superalloys

    NASA Astrophysics Data System (ADS)

    Sheng, Naicheng; Hu, Xiaobing; Liu, Jide; Jin, Tao; Sun, Xiaofeng; Hu, Zhuangqi

    2015-04-01

    Precipitates in the diffusion-affected zone (DAZ) during transient liquid phase bonding (TLP) single-crystal superalloys were observed and investigated. Small size and dendritic-shaped precipitates were identified to be M3B2 borides and intergrowth of M3B2/M5B3 borides. The orientation relationships among M3B2, M5B3, and matrix were determined using transmission electron microscope (TEM). Composition characteristics of these borides were also analyzed by TEM energy-dispersive spectrometer. Because this precipitating phenomenon deviates from the traditional parabolic transient liquid phase bonding model which assumed a precipitates free DAZ during TLP bonding, some correlations between the deviation of the isothermal solidification kinetics and these newly observed precipitating behaviors were discussed and rationalized when bonding the interlayer containing the high diffusivity melting point depressant elements and substrates of low solubility.

  9. CTX-M-1, CTX-M-3, and CTX-M-14 β-Lactamases from Enterobacteriaceae Isolated in France

    PubMed Central

    Dutour, C.; Bonnet, R.; Marchandin, H.; Boyer, M.; Chanal, C.; Sirot, D.; Sirot, J.

    2002-01-01

    Six clinical CTX-M-producing isolates of the family Enterobacteriaceae were detected between 1999 and 2000 in different French hospitals. Two strains produced CTX-M-1 and CTX-M-3 and four strains produced CTX-M-14, a mutant Ala-231→Val of CTX-M-9. A putative transposable element, ISEcp-1, was located 43 bp upstream of all the blaCTX-M genes. Two CTX-M-14-encoding plasmids exhibited similar restriction patterns. The CTX-M-1- and CTX-M-3-encoding plasmids were related to the CTX-M-1- and CTX-M-3-encoding plasmids previously reported in 1990 in France and in 1998 in Poland, respectively. PMID:11796372

  10. Phase Separation and Pair Condensation in a Spin-Imbalanced 2D Fermi Gas

    NASA Astrophysics Data System (ADS)

    Mitra, Debayan; Brown, Peter T.; Schauß, Peter; Kondov, Stanimir S.; Bakr, Waseem S.

    2016-08-01

    We study a two-component quasi-two-dimensional Fermi gas with imbalanced spin populations. We probe the gas at different interaction strengths and polarizations by measuring the density of each spin component in the trap and the pair momentum distribution after time of flight. For a wide range of experimental parameters, we observe in-trap phase separation characterized by the appearance of a spin-balanced core surrounded by a polarized gas. Our momentum space measurements indicate pair condensation in the imbalanced gas even for large polarizations where phase separation vanishes, pointing to the presence of a polarized pair condensate. Our observation of zero momentum pair condensates in 2D spin-imbalanced gases opens the way to explorations of more exotic superfluid phases that occupy a large part of the phase diagram in lower dimensions.

  11. Phase Separation and Pair Condensation in a Spin-Imbalanced 2D Fermi Gas.

    PubMed

    Mitra, Debayan; Brown, Peter T; Schauß, Peter; Kondov, Stanimir S; Bakr, Waseem S

    2016-08-26

    We study a two-component quasi-two-dimensional Fermi gas with imbalanced spin populations. We probe the gas at different interaction strengths and polarizations by measuring the density of each spin component in the trap and the pair momentum distribution after time of flight. For a wide range of experimental parameters, we observe in-trap phase separation characterized by the appearance of a spin-balanced core surrounded by a polarized gas. Our momentum space measurements indicate pair condensation in the imbalanced gas even for large polarizations where phase separation vanishes, pointing to the presence of a polarized pair condensate. Our observation of zero momentum pair condensates in 2D spin-imbalanced gases opens the way to explorations of more exotic superfluid phases that occupy a large part of the phase diagram in lower dimensions. PMID:27610853

  12. Phase Separation and Pair Condensation in a Spin-Imbalanced 2D Fermi Gas.

    PubMed

    Mitra, Debayan; Brown, Peter T; Schauß, Peter; Kondov, Stanimir S; Bakr, Waseem S

    2016-08-26

    We study a two-component quasi-two-dimensional Fermi gas with imbalanced spin populations. We probe the gas at different interaction strengths and polarizations by measuring the density of each spin component in the trap and the pair momentum distribution after time of flight. For a wide range of experimental parameters, we observe in-trap phase separation characterized by the appearance of a spin-balanced core surrounded by a polarized gas. Our momentum space measurements indicate pair condensation in the imbalanced gas even for large polarizations where phase separation vanishes, pointing to the presence of a polarized pair condensate. Our observation of zero momentum pair condensates in 2D spin-imbalanced gases opens the way to explorations of more exotic superfluid phases that occupy a large part of the phase diagram in lower dimensions.

  13. Nonlocal quantum state engineering with the Cooper pair splitter beyond the Coulomb blockade regime

    NASA Astrophysics Data System (ADS)

    Amitai, Ehud; Tiwari, Rakesh P.; Walter, Stefan; Schmidt, Thomas L.; Nigg, Simon E.

    2016-02-01

    A Cooper pair splitter consists of two quantum dots side-coupled to a conventional superconductor. Usually, the quantum dots are assumed to have a large charging energy compared to the superconducting gap, in order to suppress processes other than the coherent splitting of Cooper pairs. In this work, in contrast, we investigate the limit in which the charging energy is smaller than the superconducting gap. This allows us, in particular, to study the effect of a Zeeman field comparable to the charging energy. We find analytically that in this parameter regime the superconductor mediates an interdot tunneling term with a spin symmetry determined by the Zeeman field. Together with electrostatically tunable quantum dots, we show that this makes it possible to engineer a spin triplet state shared between the quantum dots. Compared to previous works, we thus extend the capabilities of the Cooper pair splitter to create entangled nonlocal electron pairs.

  14. Paired Learning: Tutoring by Non-Teachers. Incorporating "The Paired Reading Bulletin" No. 5.

    ERIC Educational Resources Information Center

    Paired Reading Bulletin, 1989

    1989-01-01

    The eight papers constituting the Proceedings of the fourth National Paired Reading Conference are published in an annual bulletin of the Paired Reading Project, together with seven papers constituting the Supplementary Proceedings of the Peer Tutoring Conference, and nine feature articles, as follows: (1) "Whole-School Policy on Parental…

  15. The dual specificity phosphatases M3/6 and MKP-3 are highly selective for inactivation of distinct mitogen-activated protein kinases.

    PubMed

    Muda, M; Theodosiou, A; Rodrigues, N; Boschert, U; Camps, M; Gillieron, C; Davies, K; Ashworth, A; Arkinstall, S

    1996-11-01

    The mitogen-activated protein (MAP) kinase family includes extracellular signal-regulated kinase (ERK), c-Jun NH2-terminal kinase/stress-activated protein kinase (JNK/SAPK) and p38/RK/CSBP (p38) as structurally and functionally distinct enzyme classes. Here we describe two new dual specificity phosphatases of the CL100/MKP-1 family that are selective for inactivating ERK or JNK/SAPK and p38 MAP kinases when expressed in COS-7 cells. M3/6 is the first phosphatase of this family to display highly specific inactivation of JNK/SAPK and p38 MAP kinases. Although stress-induced activation of p54 SAPKbeta, p46 SAPKgamma (JNK1) or p38 MAP kinases is abolished upon co-transfection with increasing amounts of M3/6 plasmid, epidermal growth factor-stimulated ERK1 is remarkably insensitive even to the highest levels of M3/6 expression obtained. In contrast to M3/6, the dual specificity phosphatase MKP-3 is selective for inactivation of ERK family MAP kinases. Low level expression of MKP-3 blocks totally epidermal growth factor-stimulated ERK1, whereas stress-induced activation of p54 SAPKbeta and p38 MAP kinases is inhibited only partially under identical conditions. Selective regulation by M3/6 and MKP-3 was also observed upon chronic MAP kinase activation by constitutive p21(ras) GTPases. Hence, although M3/6 expression effectively blocked p54 SAPKbeta activation by p21(rac) (G12V), ERK1 activated by p21(ras) (G12V) was insensitive to this phosphatase. ERK1 activation by oncogenic p21(ras) was, however, blocked totally by co-expression of MKP-3. This is the first report demonstrating reciprocally selective inhibition of different MAP kinases by two distinct dual specificity phosphatases.

  16. Effect of the stability of hydrogen-bonded ion pairs with organic amines on transdermal penetration of teriflunomide.

    PubMed

    Xi, Honglei; Cun, Dongmei; Wang, Zhongyan; Shang, Lei; Song, Wenting; Mu, Liwei; Fang, Liang

    2012-10-15

    The aim of this work was to investigate the effect of the stability of hydrogen-bonded ion pairs with organic amines on transdermal penetration of teriflunomide (TEF). Five organic amines, diethylamine (DEtA), triethylamine (TEtA), diethanolamine (DEA), triethanolamine (TEA), and N-(2'-hydroxyethanol)-piperdine (NP), were chosen to form ion pairs with TEF separately, and the passage of each TEF ion pair through the rabbit skin was evaluated in vitro. FTIR and (1)H NMR spectroscopy were performed to confirm the formation of ion pairs between TEF and organic amines in solution. The stability parameter of ion pairs in terms of ion-pair lifetimes (T(life)) was calculated from the NMR data. TEF could form ion pairs with these amines via hydrogen bond. The formation of ion pairs enhanced the percutaneous absorption of TEF except TEF-DEA. It was found that, for most studied organic amines, the longer the ion-pair lifetime, the higher the flux of skin permeation. The stability of TEF ion pairs was a pivotal factor influencing the skin permeation of TEF. PMID:22796174

  17. Length and Amino Acid Sequence of Peptides Substituted for the 5-HT3A Receptor M3M4 Loop May Affect Channel Expression and Desensitization

    PubMed Central

    McKinnon, Nicole K.; Bali, Moez; Akabas, Myles H.

    2012-01-01

    5-HT3A receptors are pentameric neurotransmitter-gated ion channels in the Cys-loop receptor family. Each subunit contains an extracellular domain, four transmembrane segments (M1, M2, M3, M4) and a 115 residue intracellular loop between M3 and M4. In contrast, the M3M4 loop in prokaryotic homologues is <15 residues. To investigate the limits of M3M4 loop length and composition on channel function we replaced the 5-HT3A M3M4 loop with two to seven alanine residues (5-HT3A-An = 2–7). Mutants were expressed in Xenopus laevis oocytes and characterized using two electrode voltage clamp recording. All mutants were functional. The 5-HT EC50's were at most 5-fold greater than wild-type (WT). The desensitization rate differed significantly among the mutants. Desensitization rates for 5-HT3A-A2, 5-HT3A-A4, 5-HT3A-A6, and 5-HT3A-A7 were similar to WT. In contrast, 5-HT3A-A3 and 5-HT3A-A5 had desensitization rates at least an order of magnitude faster than WT. The one Ala loop construct, 5-HT3A-A1, entered a non-functional state from which it did not recover after the first 5-HT application. These results suggest that the large M3M4 loop of eukaryotic Cys-loop channels is not required for receptor assembly or function. However, loop length and amino acid composition can effect channel expression and desensitization. We infer that the cytoplasmic ends of the M3 and M4 segments may undergo conformational changes during channel gating and desensitization and/or the loop may influence the position and mobility of these segments as they undergo gating-induced conformational changes. Altering structure or conformational mobility of the cytoplasmic ends of M3 and M4 may be the basis by which phosphorylation or protein binding to the cytoplasmic loop alters channel function. PMID:22539982

  18. Extracting an entangled photon pair from collectively decohered pairs at a telecommunication wavelength.

    PubMed

    Tsujimoto, Yoshiaki; Sugiura, Yukihiro; Ando, Makoto; Katsuse, Daisuke; Ikuta, Rikizo; Yamamoto, Takashi; Koashi, Masato; Imoto, Nobuyuki

    2015-05-18

    We experimentally demonstrated entanglement extraction scheme by using photons at the telecommunication band for optical-fiber-based quantum communications. We generated two pairs of non-degenerate polarization entangled photons at 780 nm and 1551 nm by spontaneous parametric down-conversion and distributed the two photons at 1551 nm through a collective phase damping channel which gives the same amount of random phase shift on the two photons. Through local operation and classical communication, we extracted an entangled photon pair from two phase-disturbed photon pairs. An observed fidelity of the extracted photon pair to a maximally entangled photon pair was 0.73 ± 0.07 which clearly shows the recovery of entanglement.

  19. Reducing Phosphorus Runoff and Leaching from Poultry Litter with Alum: Twenty-Year Small Plot and Paired-Watershed Studies.

    PubMed

    Huang, Lidong; Moore, Philip A; Kleinman, Peter J A; Elkin, Kyle R; Savin, Mary C; Pote, Daniel H; Edwards, Dwayne R

    2016-07-01

    Treating poultry litter with alum has been shown to lower ammonia (NH) emissions and phosphorus (P) runoff losses. Two long-term studies were conducted to assess the effects of alum-treated poultry litter on P availability, leaching, and runoff under pasture conditions. From 1995 to 2015, litter was applied annually in a paired watershed study comparing alum-treated and untreated litter and in a small plot study comparing 13 treatments (an unfertilized control, four rates of alum-treated litter, four rates of untreated litter, and four rates of NHNO). In the paired watershed study, total P loads in runoff were 231% higher from pasture receiving untreated litter (1.96 kg P ha) than from that receiving alum-treated litter (0.85 kg P ha). In both studies, alum-treated litter resulted in significantly higher Mehlich III P (M3-P) and lower water-extractable P at the soil surface, reflecting greater retention of applied P and lesser availability of that P to runoff or leaching. In soils fertilized with alum-treated litter, M3-P was much higher when analyzed by inductively coupled argon plasma emission spectrometry than by colorimetry, possibly due to the formation of aluminum phytate. Indeed, alum-treated poultry litter leached less P over the 20-yr study: M3-P at 10 to 50 cm was 266% greater in plots fertilized with untreated litter (331 kg M3-P ha) than with alum-treated litter (124 kg M3-P ha). This research provides compelling evidence that treating poultry litter with alum provides short-term and long-term benefits to P conservation and water quality. PMID:27380092

  20. Reducing Phosphorus Runoff and Leaching from Poultry Litter with Alum: Twenty-Year Small Plot and Paired-Watershed Studies.

    PubMed

    Huang, Lidong; Moore, Philip A; Kleinman, Peter J A; Elkin, Kyle R; Savin, Mary C; Pote, Daniel H; Edwards, Dwayne R

    2016-07-01

    Treating poultry litter with alum has been shown to lower ammonia (NH) emissions and phosphorus (P) runoff losses. Two long-term studies were conducted to assess the effects of alum-treated poultry litter on P availability, leaching, and runoff under pasture conditions. From 1995 to 2015, litter was applied annually in a paired watershed study comparing alum-treated and untreated litter and in a small plot study comparing 13 treatments (an unfertilized control, four rates of alum-treated litter, four rates of untreated litter, and four rates of NHNO). In the paired watershed study, total P loads in runoff were 231% higher from pasture receiving untreated litter (1.96 kg P ha) than from that receiving alum-treated litter (0.85 kg P ha). In both studies, alum-treated litter resulted in significantly higher Mehlich III P (M3-P) and lower water-extractable P at the soil surface, reflecting greater retention of applied P and lesser availability of that P to runoff or leaching. In soils fertilized with alum-treated litter, M3-P was much higher when analyzed by inductively coupled argon plasma emission spectrometry than by colorimetry, possibly due to the formation of aluminum phytate. Indeed, alum-treated poultry litter leached less P over the 20-yr study: M3-P at 10 to 50 cm was 266% greater in plots fertilized with untreated litter (331 kg M3-P ha) than with alum-treated litter (124 kg M3-P ha). This research provides compelling evidence that treating poultry litter with alum provides short-term and long-term benefits to P conservation and water quality.

  1. Twisted Pair Of Insulated Wires Senses Moisture

    NASA Technical Reports Server (NTRS)

    Laue, Eric G.; Stephens, James B.

    1989-01-01

    Sensitivity of electronic moisture sensor to low levels of moisture increased by new electrode configuration. Moisture-sensing circuit described in "Low-Cost Humidity Sensor" (NPO-16544). New twisted pair of wires takes place of flat-plate capacitor in circuit. Configuration allows for thermal expansion and contraction of polymer while maintaining nearly constant area of contact between polymer and wires.

  2. A Novel Approach for Collaborative Pair Programming

    ERIC Educational Resources Information Center

    Goel, Sanjay; Kathuria, Vanshi

    2010-01-01

    The majority of an engineer's time in the software industry is spent working with other programmers. Agile methods of software development like eXtreme Programming strongly rely upon practices like daily meetings and pair programming. Hence, the need to learn the skill of working collaboratively is of primary importance for software developers.…

  3. Turbulent Particle Pair Diffusion Using Kinematic Simulations

    NASA Astrophysics Data System (ADS)

    Malik, Nadeem

    2015-11-01

    Sweeping errors in Kinematic Simulations (KS) have been shown to be negligible in turbulent flows with extended inertial subranges up to at least 1pair diffusivity K = < Δ . v > in KS may therefore be a genuine effect, challenging previous assumptions that in turbulence with generalized power-law energy spectra, E (k) ~k-p for 1 <= 3, locality would lead to, K ~σΔγ , where σΔ = [ <Δ2 > ]1/2 , Δ is the pair separation, v is the pair relative velocity, < > is the ensemble average, and γ = (1 + p) / 2 . For Kolmogorov turbulence this gives, K ~σΔ4 / 3 . A new analysis, supported by KS confirms that both local and non-local effects govern the pair diffusion process, leading to, K ~σΔγp , where now γp > γ for Kolmogorov turbulence, K ~σΔ1 . 53 . Thus non-local diffusional processes cannot be neglected, and this may have important consequences for the general theory of turbulence. The author acknowledge financial support from SABIC, #SB101011.

  4. Phenomena, dynamics and instabilities of vortex pairs

    NASA Astrophysics Data System (ADS)

    Williamson, C. H. K.; Leweke, T.; Asselin, D. J.; Harris, D. M.

    2014-12-01

    Our motivation for studying the dynamics of vortex pairs stems initially from an interest in the trailing wake vortices from aircraft and the dynamics of longitudinal vortices close to a vehicle surface. However, our motivation also comes from the fact that vortex-vortex interactions and vortex-wall interactions are fundamental to many turbulent flows. The intent of the paper is to present an overview of some of our recent work concerning the formation and structure of counter-rotating vortex pairs. We are interested in the long-wave and short-wave three-dimensional instabilities that evolve for an isolated vortex pair, but also we would like to know how vortex pairs interact with a wall, including both two-dimensional interactions, and also the influence of the surface on the three-dimensional instabilities. The emphasis of this presentation is on physical mechanisms by which vortices interact with each other and with surfaces, principally from an experimental approach, but also coupled with analytical studies.

  5. Assessing Paired Orals: Raters' Orientation to Interaction

    ERIC Educational Resources Information Center

    Ducasse, Ana Maria; Brown, Annie

    2009-01-01

    Speaking tasks involving peer-to-peer candidate interaction are increasingly being incorporated into language proficiency assessments, in both large-scale international testing contexts, and in smaller-scale, for example course-related, ones. This growth in the popularity and use of paired and group orals has stimulated research, particularly into…

  6. Pairing, pseudogap and Fermi arcs in cuprates

    DOE PAGES

    Kaminski, Adam; Kondo, Takeshi; Takeuchi, Tsunehiro; Gu, Genda

    2014-04-29

    We use Angle Resolved Photoemission Spectroscopy (ARPES) to study the relationship between the pseudogap, pairing and Fermi arcs in cuprates. High quality data measured over a wide range of dopings reveals a consistent picture of Fermiology and pairing in these materials. The pseudogap is due to an ordered state that competes with superconductivity rather than preformed pairs. Pairing does occur below Tpair ~ 150K and significantly above Tc, but well below T* and the doping dependence of this temperature scale is distinct from that of the pseudogap. The d-wave gap is present below Tpair, and its interplay with strong scatteringmore » creates “artificial” Fermi arcs for Tc ≤ T ≤ Tpair. However, above Tpair, the pseudogap exists only at the antipodal region. This leads to presence of real, gapless Fermi arcs close to the node. The length of these arcs remains constant up to T*, where the full Fermi surface is recovered. As a result, we demonstrate that these findings resolve a number of seemingly contradictory scenarios.« less

  7. Ion Pairing in Alkali Nitrate Electrolyte Solutions.

    PubMed

    Xie, Wen Jun; Zhang, Zhen; Gao, Yi Qin

    2016-03-10

    In this study, we investigate the thermodynamics of alkali nitrate salt solutions, especially the formation of contact ion pairs between alkali cation and nitrate anion. The ion-pairing propensity shows an order of LiNO3 < NaNO3 < KNO3. Such results explain the salt activity coefficients and suggest that the empirical "law of matching water affinity" is followed by these alkali nitrate salt solutions. The spatial patterns of contact ion pairs are different in the three salt solutions studied here: Li(+) forms the contact ion pair with only one oxygen of the nitrate while Na(+) and K(+) can also be shared by two oxygens of the nitrate. In reproducing the salt activity coefficient using Kirkwood-Buff theory, we find that it is essential to include electronic polarization for Li(+) which has a high charge density. The electronic continuum correction for nonpolarizable force field significantly improves the agreement between the calculated activity coefficients and their experimental values. This approach also improves the performance of the force field on salt solubility. From these two aspects, this study suggests that electronic continuum correction can be a promising approach to force-field development for ions with high charge densities. PMID:26901167

  8. Fermionic Paired Superfluids at High Rotation Rate

    NASA Astrophysics Data System (ADS)

    Veillette, Martin Y.; Sheehy, Daniel E.; Gurarie, Victor; Radzihovsky, Leo

    2006-03-01

    I will describe our recent work on rotating resonantly-paired superfluids, mapping out the Feshbach resonance detuning, temperature and rotational frequency phase diagram. I will compare our predictions with the recent experiments on degenerate atomic ^6Li gases across a Feshbach resonance [Zwierlein et al. Nature 435, 1047 (2005)] and will make proposals for future experiments in such systems.

  9. Evolution of displays within the pair bond

    PubMed Central

    Servedio, Maria R.; Price, Trevor D.; Lande, Russell

    2013-01-01

    Although sexual selection is an important cause of display evolution, in socially monogamous species (e.g. many birds), displays continue after formation of the pair bond. Here, we consider that these displays evolve because they stimulate the partner to increase investment in offspring. Our study is motivated by elaborate mutual displays in species that are largely monomorphic and have long-term pair bonds (e.g. the great crested grebe, Podiceps cristatus) and by many empirical results evidencing that display manipulation affects parental investment. Using population genetic models, we show that a necessary condition for the permanent establishment of mutual displays in the pair bond is that the benefit of investment by the pair is more than twice that resulting from investment by a single individual. Pre-existing biases to respond to displays by increased investment are a necessary component of display evolution. We also consider examples where one sex (e.g. males) stimulates increased investment in offspring by the other sex. Here, display and additional investment cannot evolve permanently, but can increase and linger at high frequency for a long time before loss. We discuss how such transient effects may lead to the evolution of permanent displays as a result of evolution at additional loci. PMID:23427172

  10. Pairing the Adult Learner and Boutique Wineries

    ERIC Educational Resources Information Center

    Holyoke, Laura; Heath-Simpson, Delta

    2013-01-01

    This study explored connections between adult learners and their experiences in the context of small boutique wineries operating in the start-up phase of the organizational life cycle. The research objective was to gain insight regarding the pairing of adult learners with the entering of a specialty industry. Fourteen individuals from four…

  11. Ion Pairing in Alkali Nitrate Electrolyte Solutions.

    PubMed

    Xie, Wen Jun; Zhang, Zhen; Gao, Yi Qin

    2016-03-10

    In this study, we investigate the thermodynamics of alkali nitrate salt solutions, especially the formation of contact ion pairs between alkali cation and nitrate anion. The ion-pairing propensity shows an order of LiNO3 < NaNO3 < KNO3. Such results explain the salt activity coefficients and suggest that the empirical "law of matching water affinity" is followed by these alkali nitrate salt solutions. The spatial patterns of contact ion pairs are different in the three salt solutions studied here: Li(+) forms the contact ion pair with only one oxygen of the nitrate while Na(+) and K(+) can also be shared by two oxygens of the nitrate. In reproducing the salt activity coefficient using Kirkwood-Buff theory, we find that it is essential to include electronic polarization for Li(+) which has a high charge density. The electronic continuum correction for nonpolarizable force field significantly improves the agreement between the calculated activity coefficients and their experimental values. This approach also improves the performance of the force field on salt solubility. From these two aspects, this study suggests that electronic continuum correction can be a promising approach to force-field development for ions with high charge densities.

  12. Quantum physics: Photons paired with phonons

    NASA Astrophysics Data System (ADS)

    Blencowe, Miles

    2016-02-01

    The force exerted by light on an object has been used to pair photons with quantum units of mechanical vibration. This paves the way for mechanical oscillators to act as interfaces between photons and other quantum systems. See Letter p.313

  13. Paired Field Placements: A Means for Collaboration

    ERIC Educational Resources Information Center

    Gardiner, Wendy; Robinson, Karen Shipley

    2009-01-01

    In this qualitative study, pairs of preservice teachers were placed with single cooperating teachers in a 100-hour urban field placement. The question guiding this research was would preservice teachers collaborate in ways that contributed to their professional development and if so why, how, and to what end? Results from field notes, multiple…

  14. Analysis of Paired Comparison Data Using Mx

    ERIC Educational Resources Information Center

    Tsai, Rung-Ching; Wu, Tsung-Lin

    2004-01-01

    By postulating that the random utilities associated with the choice options follow a multivariate normal distribution, Thurstonian models (Thurstone, 1927) provide a straightforward representation of paired comparison data. The use of Monte Carlo Expectation-Maximization (MCEM) algorithms and limited information approaches have been proposed to…

  15. Primordial nuggets survival and QCD pairing

    NASA Astrophysics Data System (ADS)

    Lugones, G.; Horvath, J. E.

    2004-03-01

    We reexamine the problem of boiling and surface evaporation of quark nuggets in the cosmological quark-hadron transition with the explicit consideration of pairing between quarks in a color-flavor locked state. Assuming that primordial quark nuggets are actually formed, we analyze the consequences of pairing on the rates of boiling and surface evaporation in order to determine whether they could have survived with substantial mass. We find a substantial quenching of the evaporation+boiling processes, which suggests the survival of primordial nuggets for the currently considered range of the pairing gap Δ. Boiling is shown to depend on the competition of an increased stability window and the suppression of the rate, and is not likely to dominate the destruction of the nuggets. If surface evaporation dominates, the fate of the nuggets depends on the features of the initial mass spectrum of the nuggets, their evaporation rate, and the value of the pairing gap, as shown and discussed in the text.

  16. Asteroid clusters similar to asteroid pairs

    NASA Astrophysics Data System (ADS)

    Pravec, Petr; Vokrouhlicky, David; Fatka, Petr; Kusnirák, Peter; Hornoch, Kamil; Galád, Adrián

    2016-10-01

    We study five small, tight and young clusters of asteroids. They are placed around following largest (primary) bodies: (11842) Kap'bos, (14627) Emilkowalski, (16598) 1992 YC2, (21509) Lucascavin and (39991) 1998 HR37. Each cluster has 2-4 secondaries that are tightly clustered around the primary body, with distance in the 5-dimensional space of mean orbital elements mostly within 10 m/s, and always < 23 m/s. Backward orbital integrations indicate that they formed between 105 and 106 yr ago. In the P1-q space, where P1 is the primary's spin period and q = Σ Mj/M1 is the total secondary-to-primary mass ratio, the clusters lie in the same range as asteroid pairs formed by rotational fission. We have extended the model of a proto-system separation after rotational fission by Pravec et al. (2010) for application to systems with more than one secondary and found a perfect match for the five tight clusters. We find these clusters to be similar to asteroid pairs and we suggest that they are "extended pairs", having 2-4 escaped secondaries rather than just one secondary as in the case of an asteroid pair. We compare them to six young mini-families (1270) Datura, (2384) Schulhof, (3152) Jones, (6825) Irvine, (10321) Rampo and (20674) 1999 VT1. These mini-families have similar ages, but they have a higher number of members and/or they show a significantly larger spread in the mean orbital elements (dmean on an order of tens m/s) than the five tight clusters. In the P1-q space, all but one of the mini-families lie in the same range as asteroid pairs and the tight clusters; the exception is the mini-family of (3152) Jones which appears to be a collisional family. A possibility that the other five mini-families were also formed by rotational fission as we suggest for the tight clusters ("extended asteroid pairs") is being explored.Reference:Pravec, P., et al. Formation of asteroid pairs by rotational fission. Nature 466, 1085-1088.

  17. Binaries and triples among asteroid pairs

    NASA Astrophysics Data System (ADS)

    Pravec, Petr; Scheirich, Peter; Kušnirák, Peter; Hornoch, Kamil; Galád, Adrián

    2015-08-01

    Despite major achievements obtained during the past two decades, our knowledge of the population and properties of small binary and multiple asteroid systems is still far from advanced. There is a numerous indirect evidence for that most small asteroid systems were formed by rotational fission of cohesionless parent asteroids that were spun up to the critical frequency presumably by YORP, but details of the process are lacking. Furthermore, as we proceed with observations of more and more binary and paired asteroids, we reveal new facts that substantially refine and sometimes change our understanding of the asteroid systems. One significant new finding we have recently obtained is that primaries of many asteroid pairs are actually binary or triple systems. The first such case found is (3749) Balam (Vokrouhlický, ApJL 706, L37, 2009). We have found 9 more binary systems among asteroid pairs within our ongoing NEOSource photometric project since October 2012. They are (6369) 1983 UC, (8306) Shoko, (9783) Tensho-kan, (10123) Fideoja, (21436) Chaoyichi, (43008) 1999 UD31, (44620) 1999 RS43, (46829) 1998 OS14 and (80218) 1999 VO123. We will review their characteristics. These paired binaries as we call them are mostly similar to binaries in the general ("background") population (of unpaired asteroids), but there are a few trends. The paired binaries tend to have larger secondaries with D_2/D_1 = 0.3 to 0.5 and they also tend to be wider systems with 8 of the 10 having orbital periods between 30 and 81 hours, than average among binaries in the general population. There may be also a larger fraction of triples; (3749) Balam is a confirmed triple, having a larger close and a smaller distant satellite, and (8306) Shoko and (10123) Fideoja are suspect triples as they show additional rotational lightcurve components with periods of 61 and 38.8 h that differ from the orbital period of 36.2 and 56.5 h, respectively. The unbound secondaries tend to be of the same size or

  18. New acceptor-bridge-donor strategy for enhancing NLO response with long-range excess electron transfer from the NH2...M/M3O donor (M = Li, Na, K) to inside the electron hole cage C20F19 acceptor through the unusual σ chain bridge (CH2)4.

    PubMed

    Bai, Yang; Zhou, Zhong-Jun; Wang, Jia-Jun; Li, Ying; Wu, Di; Chen, Wei; Li, Zhi-Ru; Sun, Chia-Chung

    2013-04-01

    Using the strong electron hole cage C20F19 acceptor, the NH2...M/M3O (M = Li, Na, and K) complicated donors with excess electron, and the unusual σ chain (CH2)4 bridge, we construct a new kind of electride molecular salt e(-)@C20F19-(CH2)4-NH2...M(+)/M3O(+) (M = Li, Na, and K) with excess electron anion inside the hole cage (to be encapsulated excess electron-hole pair) serving as a new A-B-D strategy for enhancing nonlinear optical (NLO) response. An interesting push-pull mechanism of excess electron generation and its long-range transfer is exhibited. The excess electron is pushed out from the (super)alkali atom M/M3O by the lone pair of NH2 in the donor and further pulled inside the hole cage C20F19 acceptor through the efficient long σ chain (CH2)4 bridge. Owing to the long-range electron transfer, the new designed electride molecular salts with the excess electron-hole pair exhibit large NLO response. For the e(-)@C20F19-(CH2)4-NH2...Na(+), its large first hyperpolarizability (β0) reaches up to 9.5 × 10(6) au, which is about 2.4 × 10(4) times the 400 au for the relative e(-)@C20F20...Na(+) without the extended chain (CH2)4-NH2. It is shown that the new strategy is considerably efficient in enhancing the NLO response for the salts. In addition, the effects of different bridges and alkali atomic number on β0 are also exhibited. Further, three modulating factors are found for enhancing NLO response. They are the σ chain bridge, bridge-end group with lone pair, and (super)alkali atom. The new knowledge may be significant for designing new NLO materials and electronic devices with electrons inside the cages. They may also be the basis of establishing potential organic chemistry with electron-hole pair.

  19. Muscarinic acetylcholine receptor M1 and M3 subtypes mediate acetylcholine-induced endothelium-independent vasodilatation in rat mesenteric arteries.

    PubMed

    Tangsucharit, Panot; Takatori, Shingo; Zamami, Yoshito; Goda, Mitsuhiro; Pakdeechote, Poungrat; Kawasaki, Hiromu; Takayama, Fusako

    2016-01-01

    The present study investigated pharmacological characterizations of muscarinic acetylcholine receptor (AChR) subtypes involving ACh-induced endothelium-independent vasodilatation in rat mesenteric arteries. Changes in perfusion pressure to periarterial nerve stimulation and ACh were measured before and after the perfusion of Krebs solution containing muscarinic receptor antagonists. Distributions of muscarinic AChR subtypes in mesenteric arteries with an intact endothelium were studied using Western blotting. The expression level of M1 and M3 was significantly greater than that of M2. Endothelium removal significantly decreased expression levels of M2 and M3, but not M1. In perfused mesenteric vascular beds with intact endothelium and active tone, exogenous ACh (1, 10, and 100 nmol) produced concentration-dependent and long-lasting vasodilatations. In endothelium-denuded preparations, relaxation to ACh (1 nmol) disappeared, but ACh at 10 and 100 nmol caused long-lasting vasodilatations, which were markedly blocked by the treatment of pirenzepine (M1 antagonist) or 4-DAMP (M1 and M3 antagonist) plus hexamethonium (nicotinic AChR antagonist), but not methoctramine (M2 and M4 antagonist). These results suggest that muscarinic AChR subtypes, mainly M1, distribute throughout the rat mesenteric arteries, and that activation of M1 and/or M3 which may be located on CGRPergic nerves releases CGRP, causing an endothelium-independent vasodilatation.

  20. Comparison of the space radiation environment at Foton M3 satellite altitudes and on aircraft altitudes for minimum of solar activity

    NASA Astrophysics Data System (ADS)

    Ploc, Ondrej; Dachev, Tsvetan; Spurny, Frantisek; Tomov, Borislav; Dimitrov, Plamen; Matviichuk, Yury; Bankov, Nikolay

    The space radiation environments at Foton M3 and aircraft altitudes were measured by using of practically equal silicon detector based on a deposited energy spectrometers in the fall of 2007. The aircraft measurements were performed on commercial flights of CSA airlines, while the Foton M3 measurements were inside of the ESA Biopan 6 experiment. Foton M3 orbit was close to circular between 260 and 289 km altitude and about 63° inclination. The relatively high inclination and small shielding of the detector (0.81 g/cm2 ) allow us to observe doses by electrons in the outer radiation belt as high as 2.3 mGy/hour. The comparison of the total GCR deposited doses for the Foton M3 time interval, which coincides with the absolute cycle 23 minimum of the solar activity is about 15% higher than the measured during the Foton M2 satellite doses in 2005. Comparisons of the latitudinal profiles for ISS in 2001, Foton 2 and 3 satellites and aircrafts show that the ratio of doses is as 1:2:3. Aircraft measurements are characterised through average values of exposure during frequent, statistically well based measurements on the routes Prague - New York. Dose absorbed in Si-detector per flight on these routes was about 8% higher in 2007 than in 2005. Different comparisons with the existing models for the radiation environment on aircraft and spacecraft altitudes are presented in the paper also and discussed.

  1. Reduction in HLA-DR, HLA-DQ and HLA-DP expression by Leu-M3+ cells from the peripheral blood of patients with thermal injury.

    PubMed Central

    Gibbons, R A; Martinez, O M; Lim, R C; Horn, J K; Garovoy, M R

    1989-01-01

    Monocytes that bear HLA Class II antigens, such as HLA-DR, HLA-DQ, or HLA-DP, are obligatory for many cell-mediated immunological processes. Patients with thermal injury suffer from hypoimmunity and are at risk for developing life-threatening septic episodes. To determine whether an alteration in expression of HLA Class II antigens is involved in the defect, monocytes from the peripheral blood of burn patients and controls were double-stained with anti-Leu-M3 and either anti-HLA-DR, HLA-DQ, or HLA-DP monoclonal antibodies. As analysed by flow cytometry the percentage of Leu-M3+ monocytes from the peripheral blood from patients and controls was the same. The percentage of Leu-M3+ monocytes bearing the HLA Class II antigens and the density of antigen on the monocytes, however, was significantly reduced post-burn compared with controls. In nearly all cases these changes were detected as early as 24 h post-burn before any drug therapy was implemented. In-vivo re-expression of normal levels of HLA Class II coincided with patient recovery. In-vitro exposure of post-burn Leu-M3+ cells to IFN-gamma for 72 h restored HLA Class II expression to control levels. It is possible that the reductions in HLA Class II expression may be involved in the general immunosuppression that follows thermal injury. PMID:2495202

  2. Draft Genome Sequence of Aeribacillus pallidus Strain 8m3, a Thermophilic Hydrocarbon-Oxidizing Bacterium Isolated from the Dagang Oil Field (China)

    PubMed Central

    Poltaraus, Andrey B.; Sokolova, Diyana S.; Grouzdev, Denis S.; Ivanov, Timophey M.; Malakho, Sophia G.; Korshunova, Alena V.; Rozanov, Aleksey S.; Tourova, Tatiyana P.

    2016-01-01

    The draft genome sequence of Aeribacillus pallidus strain 8m3, a thermophilic aerobic oil-oxidizing bacterium isolated from production water from the Dagang high-temperature oil field, China, is presented here. The genome is annotated to provide insights into the genomic and phenotypic diversity of the genus Aeribacillus. PMID:27284131

  3. Serotype M3 and M28 Group A Streptococci Have Distinct Capacities to Evade Neutrophil and TNF-α Responses and to Invade Soft Tissues

    PubMed Central

    Stetzner, Zachary W.; Li, Dengfeng; Feng, Wenchao; Liu, Mengyao; Liu, Guanghui; Wiley, James; Lei, Benfang

    2015-01-01

    The M3 Serotype of Group A Streptococcus (GAS) is one of the three most frequent serotypes associated with severe invasive GAS infections, such as necrotizing fasciitis, in the United States and other industrialized countries. The basis for this association and hypervirulence of invasive serotype M3 GAS is not fully understood. In this study, the sequenced serotype M3 strain, MGAS315, and serotype M28 strain, MGAS6180, were characterized in parallel to determine whether contemporary M3 GAS has a higher capacity to invade soft tissues than M28 GAS. In subcutaneous infection, MGAS315 invaded almost the whole skin, inhibited neutrophil recruitment and TNF-α production, and was lethal in subcutaneous infection of mice, whereas MGAS6180 did not invade skin, induced robust neutrophil infiltration and TNF-α production, and failed to kill mice. In contrast to MGAS6180, MGAS315 had covS G1370T mutation. Either replacement of the covS1370T gene with wild-type covS in MGAS315 chromosome or in trans expression of wild-type covS in MGAS315 reduced expression of CovRS-controlled virulence genes hasA, spyCEP, and sse by >10 fold. MGAS315 covSwt lost the capacity to extensively invade skin and to inhibit neutrophil recruitment and had attenuated virulence, indicating that the covS G1370T mutation critically contribute to the hypervirulence of MGAS315. Under the background of functional CovRS, MGAS315 covSwt still caused greater lesions than MGAS6180, and, consistently under the background of covS deletion, MGAS6180 ΔcovS caused smaller lesions than MGAS315 ΔcovS. Thus, contemporary invasive M3 GAS has a higher capacity to evade neutrophil and TNF-α responses and to invade soft tissue than M28 GAS and that this skin-invading capacity of M3 GAS is maximized by natural CovRS mutations. These findings enhance our understanding of the basis for the frequent association of M3 GAS with necrotizing fasciitis. PMID:26047469

  4. Crystallization and preliminary X-ray crystallographic analysis of the variable domain of Scl2.3, a streptococcal collagen-like protein from invasive M3-type Streptococcus pyogenes.

    PubMed

    Squeglia, Flavia; Bachert, Beth; Romano, Maria; Lukomski, Slawomir; Berisio, Rita

    2013-09-01

    Streptococcal collagen-like proteins (Scls) are widely expressed by the well recognized human pathogen Streptococcus pyogenes. These surface proteins contain a signature central collagen-like region and an amino-terminal globular domain, termed the variable domain, which is protruded away from the cell surface by the collagen-like domain. Despite their recognized importance in bacterial pathogenicity, no structural information is presently available on proteins of the Scl class. The variable domain of Scl2 from invasive M3-type S. pyogenes has successfully been crystallized using vapour-diffusion methods. The crystals diffracted to 1.5 Å resolution and belonged to space group H32, with unit-cell parameters a = 44.23, b = 44.23, c = 227.83 Å. The crystal structure was solved by single-wavelength anomalous dispersion using anomalous signal from a europium chloride derivative.|

  5. Hydrologic calibration of paired watersheds using a MOSUM approach

    DOE PAGES

    Ssegane, H.; Amatya, D. M.; Muwamba, A.; Chescheir, G. M.; Appelboom, T.; Tollner, E. W.; Nettles, J. E.; Youssef, M. A.; Birgand, F.; Skaggs, R. W.

    2015-01-09

    Paired watershed studies have historically been used to quantify hydrologic effects of land use and management practices by concurrently monitoring two neighboring watersheds (a control and a treatment) during the calibration (pre-treatment) and post-treatment periods. This study characterizes seasonal water table and flow response to rainfall during the calibration period and tests a change detection technique of moving sums of recursive residuals (MOSUM) to select calibration periods for each control-treatment watershed pair when the regression coefficients for daily water table elevation (WTE) were most stable to reduce regression model uncertainty. The control and treatment watersheds included 1–3 year intensively managedmore » loblolly pine (Pinus taeda L.) with natural understory, same age loblolly pine intercropped with switchgrass (Panicum virgatum), 14–15 year thinned loblolly pine with natural understory (control), and switchgrass only. Although monitoring during the calibration period spanned 2009 to 2012, silvicultural operational practices that occurred during this period such as harvesting of existing stand and site preparation for pine and switchgrass establishment may have acted as external factors, potentially shifting hydrologic calibration relationships between control and treatment watersheds. Results indicated that MOSUM was able to detect significant changes in regression parameters for WTE due to silvicultural operations. This approach also minimized uncertainty of calibration relationships which could otherwise mask marginal treatment effects. All calibration relationships developed using this MOSUM method were quantifiable, strong, and consistent with Nash–Sutcliffe Efficiency (NSE) greater than 0.97 for WTE and NSE greater than 0.92 for daily flow, indicating its applicability for choosing calibration periods of paired watershed studies.« less

  6. Hydrologic calibration of paired watersheds using a MOSUM approach

    SciTech Connect

    Ssegane, H.; Amatya, D. M.; Muwamba, A.; Chescheir, G. M.; Appelboom, T.; Tollner, E. W.; Nettles, J. E.; Youssef, M. A.; Birgand, F.; Skaggs, R. W.

    2015-01-09

    Paired watershed studies have historically been used to quantify hydrologic effects of land use and management practices by concurrently monitoring two neighboring watersheds (a control and a treatment) during the calibration (pre-treatment) and post-treatment periods. This study characterizes seasonal water table and flow response to rainfall during the calibration period and tests a change detection technique of moving sums of recursive residuals (MOSUM) to select calibration periods for each control-treatment watershed pair when the regression coefficients for daily water table elevation (WTE) were most stable to reduce regression model uncertainty. The control and treatment watersheds included 1–3 year intensively managed loblolly pine (Pinus taeda L.) with natural understory, same age loblolly pine intercropped with switchgrass (Panicum virgatum), 14–15 year thinned loblolly pine with natural understory (control), and switchgrass only. Although monitoring during the calibration period spanned 2009 to 2012, silvicultural operational practices that occurred during this period such as harvesting of existing stand and site preparation for pine and switchgrass establishment may have acted as external factors, potentially shifting hydrologic calibration relationships between control and treatment watersheds. Results indicated that MOSUM was able to detect significant changes in regression parameters for WTE due to silvicultural operations. This approach also minimized uncertainty of calibration relationships which could otherwise mask marginal treatment effects. All calibration relationships developed using this MOSUM method were quantifiable, strong, and consistent with Nash–Sutcliffe Efficiency (NSE) greater than 0.97 for WTE and NSE greater than 0.92 for daily flow, indicating its applicability for choosing calibration periods of paired watershed studies.

  7. Linearly coupled oscillations in fully degenerate pair and warm pair-ion astrophysical plasmas

    NASA Astrophysics Data System (ADS)

    Khan, S. A.; Ilyas, M.; Wazir, Z.; Ehsan, Zahida

    2014-08-01

    In this paper we study the coexisting low frequency oscillations in strongly degenerate, magnetized, (electron-positron) pair and warm pair-ion plasma. The dispersion relations are obtained for both the cases in macroscopic quantum hydrodynamics approximation. In pair-ion case, the dispersion equation shows coupling of electrostatic and (shear) electromagnetic modes under certain circumstances with important role of ion temperature. Domain of existence of such waves and their relevance to dense degenerate astrophysical plasmas is pointed out. Results are analyzed numerically for typical systems with variation of ion concentration and ion temperature.

  8. Premeiotic events and meiotic chromosome pairing.

    PubMed

    Bennett, M D

    1984-01-01

    There is practical difficulty in identifying when meiosis begins. Moreover, because of contradictory definitions there is ambiguity and some confusion as to when, in terms of the cell cycle, premeiosis ends and meiosis begins. Nevertheless, results for several organisms show clearly that meiotic chromosome behaviour is affected by premeiotic events and especially by events during the final premeiotic mitosis and/or premeiotic interphase. This review considers only premeiotic events which do (or might) affect meiotic chromosome pairing by their effect on genomic characters, such as: chromosome number, homology, condition and position, with particular emphasis on the last. Interpreted in its widest sense 'premeiotic events affecting meiotic chromosome pairing' must include karyogamy. Moreover, while karyogamy is the normal means of achieving the diploid chromosome number and pairs of homologues essential for normal chromosome pairing, it is not the only way, as illustrated by the remarkable premeiotic adaptations seen in the apogamous ferns and the frog Rana esculenta. Little is known about the condition (including the molecular organization) of chromosomes during their approach and switch to meiosis. However, completion during premeiosis of some DNA synthesis may be essential for normal meiotic chromosome pairing. Various results (including different effects of colchicine given first at different premeiotic stages) have been claimed as evidence of one or other type of premeiotic spatial ordering of chromosomes which might favour, or be essential for, meiotic chromosome pairing. Chromosome placement has been studied recently using the electron microscope, serial thin-section, reconstruction technique. This has revealed clear evidence of non-random spatial placement of chromosomes in non-meiotic and premeiotic cells. For example, in root-tip cells of barley, Hordeum vulgare L. cv. Tuleen 346 (2n = 2x = 14), it showed: a significant spatial separation of two haploid

  9. Direct observation of base-pair stepping by RNA polymerase

    NASA Astrophysics Data System (ADS)

    Abbondanzieri, Elio A.; Greenleaf, William J.; Shaevitz, Joshua W.; Landick, Robert; Block, Steven M.

    2005-11-01

    During transcription, RNA polymerase (RNAP) moves processively along a DNA template, creating a complementary RNA. Here we present the development of an ultra-stable optical trapping system with ångström-level resolution, which we used to monitor transcriptional elongation by single molecules of Escherichia coli RNAP. Records showed discrete steps averaging 3.7 +/- 0.6Å, a distance equivalent to the mean rise per base found in B-DNA. By combining our results with quantitative gel analysis, we conclude that RNAP advances along DNA by a single base pair per nucleotide addition to the nascent RNA. We also determined the force-velocity relationship for transcription at both saturating and sub-saturating nucleotide concentrations; fits to these data returned a characteristic distance parameter equivalent to one base pair. Global fits were inconsistent with a model for movement incorporating a power stroke tightly coupled to pyrophosphate release, but consistent with a brownian ratchet model incorporating a secondary NTP binding site.

  10. Direct observation of base-pair stepping by RNA polymerase.

    PubMed

    Abbondanzieri, Elio A; Greenleaf, William J; Shaevitz, Joshua W; Landick, Robert; Block, Steven M

    2005-11-24

    During transcription, RNA polymerase (RNAP) moves processively along a DNA template, creating a complementary RNA. Here we present the development of an ultra-stable optical trapping system with ångström-level resolution, which we used to monitor transcriptional elongation by single molecules of Escherichia coli RNAP. Records showed discrete steps averaging 3.7 +/- 0.6 A, a distance equivalent to the mean rise per base found in B-DNA. By combining our results with quantitative gel analysis, we conclude that RNAP advances along DNA by a single base pair per nucleotide addition to the nascent RNA. We also determined the force-velocity relationship for transcription at both saturating and sub-saturating nucleotide concentrations; fits to these data returned a characteristic distance parameter equivalent to one base pair. Global fits were inconsistent with a model for movement incorporating a power stroke tightly coupled to pyrophosphate release, but consistent with a brownian ratchet model incorporating a secondary NTP binding site.

  11. Nuclear inertia from the time dependent pairing equations

    NASA Astrophysics Data System (ADS)

    Mirea, M.

    2016-10-01

    In a dynamical system, the momenta of inertia and the effective masses are not adiabatic quantities, but are dynamical ones that depend on the dissipated energy accumulated during motion. However, these parameters are calculated for adiabatic nuclear systems, leaving no room for dissipated energy. In this work, a formalism is elaborated in order to derive simultaneously the nuclear momenta of inertia and the effective masses by taking into account the appearance of dissipated energy for large amplitude motion of the nuclear system. The expressions that define the inertia are obtained from the variational principle. The same principle manages the time dependent pairing equations, offering estimations of the averaged dissipation energy for large amplitude motions. The model is applied to 232Th fission. The fission barrier was calculated along the least action trajectory. The dissipation energy, effective mass and moment of inertia are determined for different values of the collective velocities. The dissipation increases with the internuclear velocity in binary disintegration processes and modifies the effective mass parameters. We observed that the inertia decreases as long as the collective velocity increases to some moderate values and begins to grow for larger collective velocities. So, a dependence between the cranking mass parameters and the intrinsic excitation energy is evidenced. In order to investigate the overall effect, the half-lives are predicted for adiabatic and dynamics simulations.

  12. Contact Pairing Interaction for the Hartree-Fock-Bogoliubov Calculations

    SciTech Connect

    Dobaczewski, J.

    2001-10-18

    Properties of density-dependent contact pairing interactions in nuclei are discussed. It is shown that the pairing interaction that is intermediate between surface and volume pairing forces gives the pairing gaps that are compatible with the experimental odd-even mass staggering. Results of the deformed Hartree-Fock-Bogoliubov calculations for this ''mixed'' pairing interaction, and using the transformed harmonic oscillator basis, are presented.

  13. Electron-pair excitations and the molecular Coulomb continuum

    SciTech Connect

    Colgan, James

    2009-01-01

    Electron-pair excitations in the molecular hydrogen continuum are described by quantizing rotations of the momentum plane of the electron pair about by the pair's relative momentum. A helium-like description of the molecular pi.Joto double ionization is thus extended to higher angular momenta of the electron pair. A simple three-state superposition is found to account surprisingly well for recent observations of noncoplanar electron-pair, molecular-axis angular distributions.

  14. A search for resonant Z pair production

    SciTech Connect

    Boveia, Antonio

    2008-12-01

    I describe a search for anomalous production of Z pairs through a new massive resonance X in 2.5-2.9 fb-1 of p$\\bar{p}$ collisions at √s = 1.96 TeV using the CDFII Detector at the Fermilab Tevatron. I reconstruct Z pairs through their decays to electrons, muons, and quarks. To achieve perhaps the most efficient lepton reconstruction ever used at CDF, I apply a thorough understanding of the detector and new reconstruction software heavily revised for this purpose. In particular, I have designed and employ new general-purpose algorithms for tracking at large η in order to increase muon acceptance. Upon analyzing the unblinded signal samples, I observe no X → ZZ candidates and set upper limits on the production cross section using a Kaluza-Klein graviton-like acceptance.

  15. The Radical-Pair Mechanism of Magnetoreception.

    PubMed

    Hore, P J; Mouritsen, Henrik

    2016-07-01

    Although it has been known for almost half a century that migratory birds can detect the direction of the Earth's magnetic field, the primary sensory mechanism behind this remarkable feat is still unclear. The leading hypothesis centers on radical pairs-magnetically sensitive chemical intermediates formed by photoexcitation of cryptochrome proteins in the retina. Our primary aim here is to explain the chemical and physical aspects of the radical-pair mechanism to biologists and the biological and chemical aspects to physicists. In doing so, we review the current state of knowledge on magnetoreception mechanisms. We dare to hope that this tutorial will stimulate new interdisciplinary experimental and theoretical work that will shed much-needed additional light on this fascinating problem in sensory biology. PMID:27216936

  16. PAIR (Planning and Analysis of Inspection Resources)

    SciTech Connect

    Teichmann, T.; Santaniello, A.; Fishbone, L.G.

    1994-03-01

    The safeguards inspection effort of the International Atomic Energy Agency consists of the efforts for the Physical Inventory Verifications to close the annual material balance, Interim Inventory Verifications, conducted mainly to satisfy the Timeliness Criteria, Flow Verifications to verify the transfer of material, and Containment and Surveillance activities, which help preserve continuity of knowledge concerning the material. Estimating the requiring overall future inspection effort under a variety of conditions is an important part of Agency planning. As exemplified by the sample results provides a straightforward means to analyze `What if` situations in safeguards implementation. It thereby permits managers and analysts to study future scenarios and their effect on human resources. It is planned to introduce into PAIR a direct capability for studying costs associated with these hypothetical changes in safeguards implementation. In this way PAIR could more easily assist the Safeguards Department in its current program of investigating new safeguards approaches.

  17. A study of paired necro kidney grafts.

    PubMed

    Lamm, L U

    1979-01-01

    The comparison of the fate of kidney pairs originating from the same donor offers an opportunity to control variability in primary kidney graft survival due to characteristics of the donor. The present study on 1,303 pairs was made possible by combining the information in the Scandiatransplant registry and the EDTA follow-up file. The analysis showed that, contrary to expectation, the main variability in kidney graft survival is not donor dependent but rather due to post-nephrectomy factors. By the present approach it was possible to demonstrate a significant effect of presensitisation, HLA-A,B matching and recipient age. In contrast, transportation, and differences in sex and ABO blood group combinations seem to be of no importance for kidney graft survival.

  18. Pair correlations in neutron-rich nuclei

    SciTech Connect

    Esbensen, H.

    1995-08-01

    We started a program to study the ground-state properties of heavy, neutron-rich nuclei using the Hartree-Fock-Bogolyubov (HFB) approximation. This appears at present to be the most realistic approach for heavy nuclei that contain many loosely bound valence neutrons. The two-neutron density obtained in this approach can be decomposed into two components, one associated with the mean field and one associated with the pairing field. The latter has a structure that is quite similar to the pair-density obtained by diagonalizing the Hamiltonian for a two-neutron halo, which was studied earlier. This allows comparison of the HFB solutions against numerically exact solutions for two-neutron halos. This work is in progress. We intend to apply the HFB method to predict the ground-state properties of heavier, more neutron-rich nuclei that may be produced at future radioactive beam facilities.

  19. Dynamics and Instabilities of Vortex Pairs

    NASA Astrophysics Data System (ADS)

    Leweke, Thomas; Le Dizès, Stéphane; Williamson, Charles H. K.

    2016-01-01

    This article reviews the characteristics and behavior of counter-rotating and corotating vortex pairs, which are seemingly simple flow configurations yet immensely rich in phenomena. Since the reviews in this journal by Widnall (1975) and Spalart (1998) , who studied the fundamental structure and dynamics of vortices and airplane trailing vortices, respectively, there have been many analytical, computational, and experimental studies of vortex pair flows. We discuss two-dimensional dynamics, including the merging of same-sign vortices and the interaction with the mutually induced strain, as well as three-dimensional displacement and core instabilities resulting from this interaction. Flows subject to combined instabilities are also considered, in particular the impingement of opposite-sign vortices on a ground plane. We emphasize the physical mechanisms responsible for the flow phenomena and clearly present the key results that are useful to the reader for predicting the dynamics and instabilities of parallel vortices.

  20. A viscous vortex pair in ground effect

    NASA Astrophysics Data System (ADS)

    Peace, A. J.; Riley, N.

    1983-04-01

    Attention is given to the unsteady fluid motion which is induced when a vortex pair moves in an incompressible viscous fluid towards a plane boundary. The vortex pair at the initial instant is represented by two inviscid line vortices and the line which joins them is parallel to the boundary surface. The boundary surface may be either a rigid boundary at which the no-slip condition must be satisfied or a free surface corresponding to zero shear stress. The governing equations and a solution procedure are discussed, taking into account a finite-difference approach. Research of calculations are presented for both a non-slip boundary and a stress-free boundary. The phenomenon or rebound of the vortices from the boundary is found to occur in both cases. An explanation for this result in terms of viscous effects is provided.

  1. Dual Resolution Images from Paired Fingerprint Cards

    National Institute of Standards and Technology Data Gateway

    NIST Dual Resolution Images from Paired Fingerprint Cards (PC database for purchase)   NIST Special Database 30 is being distributed for use in development and testing of fingerprint compression and fingerprint matching systems. The database allows the user to develop and evaluate data compression algorithms for fingerprint images scanned at both 19.7 ppmm (500 dpi) and 39.4 ppmm (1000 dpi). The data consist of 36 ten-print paired cards with both the rolled and plain images scanned at 19.7 and 39.4 pixels per mm. A newer version of the compression/decompression software on the CDROM can be found at the website http://www.nist.gov/itl/iad/ig/nigos.cfm as part of the NBIS package.

  2. Asteroid Systems: Binaries, Triples, and Pairs

    NASA Astrophysics Data System (ADS)

    Margot, J.-L.; Pravec, P.; Taylor, P.; Carry, B.; Jacobson, S.

    In the past decade, the number of known binary near-Earth asteroids has more than quadrupled and the number of known large main-belt asteroids with satellites has doubled. Half a dozen triple asteroids have been discovered, and the previously unrecognized populations of asteroid pairs and small main-belt binaries have been identified. The current observational evidence confirms that small (≲20 km) binaries form by rotational fission and establishes that the Yarkovsky-O'Keefe-Radzievskii-Paddack (YORP) effect powers the spin-up process. A unifying paradigm based on rotational fission and post-fission dynamics can explain the formation of small binaries, triples, and pairs. Large (>~20 km) binaries with small satellites are most likely created during large collisions.

  3. Satellite observations of transionospheric pulse pairs

    SciTech Connect

    Holden, D.N.; Munson, C.P.; Devenport, J.C.

    1995-04-15

    The BLACKBEARD payload aboard the ALEXIS satellite has been making broadband observations in the VHF band of the radio spectrum. Since November of 1993 several hundred unusual signals have been recorded. The peculiar nature of these bursts of radio noise is that they have a duration of approximately 10 {mu}sec, are typically 20 to 40 dB brighter than the average background, and occur in pairs separated by approximately 50 {mu}sec. The authors have dubbed these emissions TransIonospheric Pulse Pairs, or TIPP events. They do not know what the source of these emissions is, but the dispersion of these signals is consistent with an origin at or near the earth`s surface. The satellite field of view and time of day when TIPP events are generally detected are consistent with regions of thunderstorm activity such as south-central Africa or Indonesia. 4 refs., 5 figs.

  4. Amperean (2k_F) pairing and the pseudo-gap phase in HiTc Cuprates

    NASA Astrophysics Data System (ADS)

    Lee, Patrick

    2015-03-01

    We propose that the pseudogap phase is a novel pairing state where electrons on the same side of the Fermi surface are paired, in strong contrast with conventional BCS theory which pairs electrons on opposite sides of the Fermi surface. The pair carries a net momentum 2k_F, forming a pair density wave. The microscopic pairing mechanism comes from a gauge theory formulation of the resonating valence bond (RVB) picture, where spinons traveling in the same direction feel an attractive force in analogy with Ampere's effects in electromagnetism. We call this Amperean pairing. Charge order appears as a subsidiary order parameter even when pair order is destroyed by phase fluctuations. Our theory gives a prediction of the ordering wave vector which is in good agreement with experiment. Furthermore, the quasiparticle spectrum from our model explains many of the unusual features reported in photoemission experiments. Finally, we propose an experiment that can directly test the idea of Amperean pairing. This work is supported by the NSF Grant Number DMR-1104498.

  5. Pairing of Cooper pairs in a Josephson junction network containing an impurity

    NASA Astrophysics Data System (ADS)

    Giuliano, Domenico; Sodano, Pasquale

    2009-10-01

    We show how to induce pairing of Cooper pairs (and, thus, 4e superconductivity) as a result of local embedding of a quantum impurity in a Josephson network fabricable with conventional junctions. We find that a boundary double sine-Gordon model provides an accurate description of the dc Josephson current patterns, as well as of the stable phases accessible to the network. We point out that tunneling of pairs of Cooper pairs is robust against quantum fluctuations, as a consequence of the time reversal invariance, arising when the central region of the network is pierced by a dimensionless magnetic flux phiv=π. We find that, for phiv=π, a stable attractive finite coupling fixed point emerges and point out its relevance for engineering a two-level quantum system with enhanced coherence.

  6. Magnetic instability and pair binding in aromatic hydrocarbon superconductors

    PubMed Central

    Huang, Zhongbing; Zhang, Chao; Lin, Hai-Qing

    2012-01-01

    Understanding magnetism and electron correlation in many unconventional superconductors is essential to explore mechanism of superconductivity. In this work, we perform a systematic numerical study of the magnetic and pair binding properties in recently discovered polycyclic aromatic hydrocarbon (PAH) superconductors including alkali-metal-doped picene, coronene, phenanthrene, and dibenzopentacene. The π-electrons on the carbon atoms of a single molecule are modelled by the one-orbital Hubbard model, and the energy difference between carbon atoms with and without hydrogen bonds is taking into account. We demonstrate that the spin polarized ground state is realized for charged molecules in the physical parameter regions, which provides a reasonable explanation of local spins observed in PAHs. In alkali-metal-doped dibenzopentacene, our results show that electron correlation may produce an effective attraction between electrons for the charged molecule with one or three added electrons. PMID:23213358

  7. Probe measurements of magnetron discharge parameters

    NASA Astrophysics Data System (ADS)

    Karzin, V.; Smirnov, V.

    2016-07-01

    Langmuir probe measurements have been carried out in a positive column discharge of a planar magnetron with a titanium target. In this work concentration and temperature of electrons is measured in positive column of magnetron discharge with Langmuir probe. Concentration of electrons is found to be on the level of 1016 m-3 at a notable distance (over 200 mm). Two groups of electrons exist: «cold» and «hot» with average temperature of 16 000 and 41 000 K respectively. Dependence of discharge parameters on working gas pressure is measured.

  8. Spectra and symmetry in nuclear pairing

    SciTech Connect

    Balantekin, A. B.; Jesus, J. H. de; Pehlivan, Y.

    2007-06-15

    We apply the algebraic Bethe ansatz technique to the nuclear pairing problem with orbit dependent coupling constants and degenerate single particle energy levels. We find the exact energies and eigenstates. We show that for a given shell, there are degeneracies between the states corresponding to less than and more than half full shell. We also provide a technique to solve the equations of Bethe ansatz.

  9. Signature scheme based on bilinear pairs

    NASA Astrophysics Data System (ADS)

    Tong, Rui Y.; Geng, Yong J.

    2013-03-01

    An identity-based signature scheme is proposed by using bilinear pairs technology. The scheme uses user's identity information as public key such as email address, IP address, telephone number so that it erases the cost of forming and managing public key infrastructure and avoids the problem of user private generating center generating forgery signature by using CL-PKC framework to generate user's private key.

  10. Electrostatic drift modes in quantum pair plasmas

    SciTech Connect

    Ren Haijun; Cao Jintao; Wu Zhengwei

    2008-10-15

    Electrostatic drift waves in a nonuniform quantum magnetized electron-positron (pair) plasma are investigated. An explicit and straightforward analytical expression of the fluctuation frequency is presented. The effects induced by quantum fluctuations, density gradients, and magnetic field inhomogeneity on the wave frequencies are discussed and a purely quantum drift mode appears. The present analytical investigations are relevant to dense astrophysical objects as well as laboratory ultracold plasmas.

  11. Trident Pair Production in Strong Laser Pulses

    SciTech Connect

    Ilderton, Anton

    2011-01-14

    We calculate the trident pair production amplitude in a strong laser background. We allow for finite pulse durations, while still treating the laser fields nonperturbatively in strong-field QED. Our approach reveals explicitly the individual contributions of the one-step and two-step processes. We also expose the role gauge invariance plays in the amplitudes and discuss the relation between our results and the optical theorem.

  12. Major-Merger Galaxy Pairs at Z = 0: Dust Properties and Companion Morphology

    NASA Astrophysics Data System (ADS)

    Domingue, Donovan L.; Cao, Chen; Xu, C. Kevin; Jarrett, Thomas H.; Ronca, Joseph; Hill, Emily; Jacques, Allison

    2016-10-01

    We present an analysis of dust properties of a sample of close major-merger galaxy pairs selected by K s magnitude and redshift. The pairs represent the two populations of spiral-spiral (S+S) and mixed morphology spiral-elliptical (S+E). The Code Investigating GALaxy Emission software is used to fit dust models to the Two Micron All Sky Survey, Wide-Field Infrared Survey Explorer, and Herschel flux density measurements, and to derive the parameters describing the polycyclic aromatic hydrocarbons contribution, interstellar radiation field, and photodissociation regions. Model fits verify our previous Spitzer Space Telescope analysis that S+S and S+E pairs do not have the same level of enhancement of star formation and differ in dust composition. The spirals of mixed-morphology galaxy pairs do not exhibit the enhancements in interstellar radiation field and therefore dust temperature for spirals in S+S pairs in contrast to what would be expected according to standard models of gas redistribution due to encounter torques. This suggests the importance of the companion environment/morphology in determining the dust properties of a spiral galaxy in a close major-merger pair.

  13. Torsion of the central pair microtubules in eukaryotic flagella due to bending-driven lateral buckling.

    PubMed

    Li, C; Ru, C Q; Mioduchowski, A

    2006-12-01

    Inspired by recent interest in torsion of the central pair microtubules in eukaryotic flagella, a novel thin-walled elastic beam model is suggested to study critical condition under which uniform bending of a flagellum will cause lateral/torsional buckling of the central pair. The model is directed to the central pair itself and the role of all surrounding cross-linkings inside the flagellum is modeled as an equivalent surrounding elastic medium. The model predicts that bending-driven torsion of the central pair does occur when the radius of curvature of the bent flagellum reduces to a moderate critical value typically of tens of microns. In particular, this critical value is almost independent of the flagellum length, and more sensitive to the parameters defining the surrounding elastic medium than the shear modulus of microtubules. The predicted wavelengths of the torsional buckling mode are insensitive to the flagellum length and comparable to some known related experimental data. These results indicate that torsion of the central pair microtubules in flagella is inevitable as a result of bending-driven lateral buckling. This offers an entirely new insight into the ongoing research on the mechanism of the central pair torsion.

  14. Torsion of the central pair microtubules in eukaryotic flagella due to bending-driven lateral buckling

    SciTech Connect

    Li, C.; Ru, C.Q. . E-mail: c.ru@ualberta.ca; Mioduchowski, A.

    2006-12-08

    Inspired by recent interest in torsion of the central pair microtubules in eukaryotic flagella, a novel thin-walled elastic beam model is suggested to study critical condition under which uniform bending of a flagellum will cause lateral/torsional buckling of the central pair. The model is directed to the central pair itself and the role of all surrounding cross-linkings inside the flagellum is modeled as an equivalent surrounding elastic medium. The model predicts that bending-driven torsion of the central pair does occur when the radius of curvature of the bent flagellum reduces to a moderate critical value typically of tens of microns. In particular, this critical value is almost independent of the flagellum length, and more sensitive to the parameters defining the surrounding elastic medium than the shear modulus of microtubules. The predicted wavelengths of the torsional buckling mode are insensitive to the flagellum length and comparable to some known related experimental data. These results indicate that torsion of the central pair microtubules in flagella is inevitable as a result of bending-driven lateral buckling. This offers an entirely new insight into the ongoing research on the mechanism of the central pair torsion.

  15. Grandmothering life histories and human pair bonding

    PubMed Central

    Coxworth, James E.; Kim, Peter S.; McQueen, John S.; Hawkes, Kristen

    2015-01-01

    The evolution of distinctively human life history and social organization is generally attributed to paternal provisioning based on pair bonds. Here we develop an alternative argument that connects the evolution of human pair bonds to the male-biased mating sex ratios that accompanied the evolution of human life history. We simulate an agent-based model of the grandmother hypothesis, compare simulated sex ratios to data on great apes and human hunter–gatherers, and note associations between a preponderance of males and mate guarding across taxa. Then we explore a recent model that highlights the importance of mating sex ratios for differences between birds and mammals and conclude that lessons for human evolution cannot ignore mammalian reproductive constraints. In contradiction to our claim that male-biased sex ratios are characteristically human, female-biased ratios are reported in some populations. We consider the likelihood that fertile men are undercounted and conclude that the mate-guarding hypothesis for human pair bonds gains strength from explicit links with our grandmothering life history. PMID:26351687

  16. Population of the giant pairing vibration

    NASA Astrophysics Data System (ADS)

    Laskin, M.; Casten, R. F.; Macchiavelli, A. O.; Clark, R. M.; Bucurescu, D.

    2016-03-01

    Background: The giant pairing vibration (GPV), a correlated two-nucleon mode in the second shell above the Fermi surface, has long been predicted and expected to be strongly populated in two-nucleon transfer cross sections similar to those of the normal pairing vibration. Recent experiments have provided evidence for this mode in ,15C14 but, despite sensitive studies, it has not been definitively identified in either Sn or Pb nuclei where pairing correlations are known to play a crucial role. Purpose: Our aim is to test whether features inherent to the mixing of bound and unbound levels might account for this and to study the effect in a simple and intuitively clear approach. Method: We study the mixing of unbound levels in a set of toy models that capture the essential physics of the GPV, along with a more realistic calculation including distorted-wave Born approximation transfer amplitudes. Results: The calculated (relative) cross section to populate a simulated GPV state is effectively low, compared to the case of bound levels with no widths Conclusions: The mixing turns out to be only a minor contributor to the weak population. Rather, the main reason is the melting of the GPV peak due to the width it acquires from the low orbital angular momentum single-particle states playing a dominant role in two-nucleon transfer amplitudes. This effect, in addition to a severe Q -value mismatch, may account for the elusive nature of this mode in (t ,p ) and (p ,t ) reactions.

  17. Emission from Pair Instability Supernovae with Rotation

    NASA Astrophysics Data System (ADS)

    Chatzopoulos, Emmanouil; Van Rossum, Daniel R; Whalen, Daniel J.

    2014-08-01

    Pair Instability Supernovae have been suggested as candidates for some Super Luminous Supernovae, like SN 2007bi, and can also be one of the dominant types of explosion occurring in the early Universe from massive, zero-metallicity Population III stars. The progenitors of such events can be rapidly rotating therefore exhibiting a differentevolutionary path due to the effects of rotationally-induced mixing and mass-loss.Proper identification of such events requires rigorous radiation hydrodynamics and non-localthermal equilibrium calculations that capture not only the behavior of the light curve but also the spectral evolution of these events accurately. We present radiation hydrodynamics and local and non-local thermal equilibrium radiation transport calculations for 90-140 Msun rotating pair-instability supernovae covering both the shock break-out and late light curve phases. We find that for a variety of progenitor masses these events are too dim and too red in color to account for so far observed super-luminous supernovae and do not seem to matchother known events, in terms of spectral appearance. We discuss the qualitative differences between different radiation transport treatments and compare our results with previous results from non-rotating pair-instability supernovae.

  18. Pair fireball precursors of neutron star mergers

    NASA Astrophysics Data System (ADS)

    Metzger, Brian D.; Zivancev, Charles

    2016-10-01

    If at least one neutron star (NS) is magnetized in a binary NS merger, then the orbital motion of the conducting companion during the final inspiral induces a strong voltage and current along the magnetic field lines connecting the NSs. If a modest fraction η of the extracted electromagnetic power extracted accelerates relativistic particles, the resulting gamma-ray emission a compact volume will result in the formation of an electron-positron pair fireball. Applying a steady-state pair wind model, we quantify the detectability of the precursor fireball with gamma-ray satellites. For η ˜ 1 the gamma-ray detection horizon of Dmax ≈ 10(Bd/1014 G)3/4 Mpc is much closer than the Advanced Laser Interferometer Gravitational-Wave Observatory (LIGO)/Virgo horizon of 200 Mpc, unless the NS surface magnetic field strength is very large, B_d ≲ 10^{15} G. Given the quasi-isotropic nature of the emission, mergers with weaker NS fields could contribute a nearby population of short gamma-ray bursts. Power not dissipated close to the binary is carried to infinity along the open field lines by a large-scale Poynting flux. Reconnection within this outflow, well outside of the pair photosphere, provides a potential site for non-thermal emission, such as a coherent millisecond radio burst.

  19. Grandmothering life histories and human pair bonding.

    PubMed

    Coxworth, James E; Kim, Peter S; McQueen, John S; Hawkes, Kristen

    2015-09-22

    The evolution of distinctively human life history and social organization is generally attributed to paternal provisioning based on pair bonds. Here we develop an alternative argument that connects the evolution of human pair bonds to the male-biased mating sex ratios that accompanied the evolution of human life history. We simulate an agent-based model of the grandmother hypothesis, compare simulated sex ratios to data on great apes and human hunter-gatherers, and note associations between a preponderance of males and mate guarding across taxa. Then we explore a recent model that highlights the importance of mating sex ratios for differences between birds and mammals and conclude that lessons for human evolution cannot ignore mammalian reproductive constraints. In contradiction to our claim that male-biased sex ratios are characteristically human, female-biased ratios are reported in some populations. We consider the likelihood that fertile men are undercounted and conclude that the mate-guarding hypothesis for human pair bonds gains strength from explicit links with our grandmothering life history. PMID:26351687

  20. Meiotic segregation of a homeologous chromosome pair.

    PubMed

    Maxfield Boumil, R; Kemp, B; Angelichio, M; Nilsson-Tillgren, T; Dawson, D S

    2003-03-01

    During meiosis, the alignment of homologous chromosomes facilitates their subsequent migration away from one another to opposite spindle poles at anaphase I. Recombination is part of the mechanism by which chromosomes identify their homologous partners, and serves to link the homologs in a way that, in some organisms, has been shown to promote proper attachment to the meiotic spindle. We have built a diploid strain that contains a pair of homeologous chromosomes V': one is derived from Saccharomyces cerevisiae and one originates from S. carlsbergensis. Sequence analysis reveals that these chromosomes share 71% sequence identity. The homeologs experience high levels of meiotic double-stranded breaks. Despite their relatedness and their competence to initiate recombination, the meiotic segregation behavior of the homeologous chromosomes suggests that, in most meioses, they are partitioned by a meiotic segregation system that has been shown previously to partition non-exchange chromosomes and pairs with no homology. Though the homeologous chromosomes show a degree of meiotic segregation fidelity similar to that of other non-exchange pairs, our data provide evidence that their limited sequence homology may provide some bias in meiotic partner choice. PMID:12655401

  1. Paired and interacting galaxies: Conference summary

    NASA Technical Reports Server (NTRS)

    Norman, Colin A.

    1990-01-01

    The author gives a summary of the conference proceedings. The conference began with the presentation of the basic data sets on pairs, groups, and interacting galaxies with the latter being further discussed with respect to both global properties and properties of the galactic nuclei. Then followed the theory, modelling and interpretation using analytic techniques, simulations and general modelling for spirals and ellipticals, starbursts and active galactic nuclei. Before the conference the author wrote down the three questions concerning pairs, groups and interacting galaxies that he hoped would be answered at the meeting: (1) How do they form, including the role of initial conditions, the importance of subclustering, the evolution of groups to compact groups, and the fate of compact groups; (2) How do they evolve, including issues such as relevant timescales, the role of halos and the problem of overmerging, the triggering and enhancement of star formation and activity in the galactic nuclei, and the relative importance of dwarf versus giant encounters; and (3) Are they important, including the frequency of pairs and interactions, whether merging and interactions are very important aspects of the life of a normal galaxy at formation, during its evolution, in forming bars, shells, rings, bulges, etc., and in the formation and evolution of active galaxies? Where possible he focuses on these three central issues in the summary.

  2. Study of J/psi Pair Production

    NASA Astrophysics Data System (ADS)

    Riley, Grant; CMS Collaboration

    2016-03-01

    We study the J/psi pair final state produced in proton-proton collisions at the LHC at 7 and 8 TeV center-of-mass energies with the CMS detector. The J/psi are reconstructed from their decay into muon pairs where the CMS detector provides excellent identification for muons with momenta as low as 2 GeV. In this final state, eventual resonances are predicted such as ηb, heavy quark tetra-quarks governed by strong interaction or a low-mass Higgs bosons in minimal SUSY extensions of the standard model. An important step in isolating signals is the understanding of the non-resonant J/psi pair production. Only recently based on the coss section measurements in LHCb and complementary measurements in CMS have production models been provided that not only include single-parton scattering but double-parton scattering and consider color singlet and color octet intermediate J/psi states. This measurement and the search for di-quarkonia resonances is presented here.

  3. Pairing in half-filled Landau level

    SciTech Connect

    Wang, Zhiqiang; Mandal, Ipsita; Chung, Suk Bum; Chakravarty, Sudip

    2014-12-15

    Pairing of composite fermions in half-filled Landau level state is reexamined by solving the BCS gap equation with full frequency dependent current–current interactions. Our results show that there can be a continuous transition from the Halperin–Lee–Read state to a chiral odd angular momentum Cooper pair state for short-range contact interaction. This is at odds with the previously established conclusion of first order pairing transition, in which the low frequency effective interaction was assumed for the entire frequency range. We find that even if the low frequency effective interaction is repulsive, it is compensated by the high frequency regime, which is attractive. We construct the phase diagrams and show that ℓ=1 angular momentum channel is quite different from higher angular momenta ℓ≥3. Remarkably, the full frequency dependent analysis applied to the bilayer Hall system with a total filling fraction ν=1/2 +1/2 is quantitatively changed from the previously established results but not qualitatively.

  4. Persistent Ion Pairing in Aqueous Hydrochloric Acid

    SciTech Connect

    Baer, Marcel D.; Fulton, John L.; Balasubramanian, Mahalingam; Schenter, Gregory K.; Mundy, Christopher J.

    2014-07-03

    For strong acids, like hydrochloric acid, the complete dissociation into an excess proton and conjugated base as well as the formation of independent solvated charged fragments is assumed. The existence of a chloride-Hyronium (Cl-H3O+) contact ion pairs even in moderate concentration hydrochloric acid (2.5 m) demonstrates that the counter ions do not behave merely as spectators. Through the use of modern extended X-ray absorption fine structure (EXAFS) measurements in conjunction with state-of-the-art density functional theory (DFT) simulations, we are able to obtain an unprecedented view into the molecular structure of medium to high concentrated electrolytes. Here we report that the Cl-H3O+ contact ion pair structure persists throughout the entire concentration range studied and that these structures differ significantly from moieties studied in micro-solvated hydrochloric acid clusters. Characterizing distinct populations of these ion pairs gives rise to a novel molecular level description of how to think about the activity of the proton that impacts our picture of the pH scale. Funding for CJM, GKS, and JLF was provided by DOE Office of Science, Office of Basic Energy Science, Division of Chemical Sciences, Geosciences, and Biosciences. Funding for MDB was provided throught the Laboratory Directed Research and Development program at Pacific Northwest National Laboratory. MB was funded through Argonne National Laboratory.

  5. Fundamental aspects of recoupled pair bonds. II. Recoupled pair bond dyads in carbon and sulfur difluoride

    NASA Astrophysics Data System (ADS)

    Dunning, Thom H.; Takeshita, Tyler Y.; Xu, Lu T.

    2015-01-01

    Formation of a bond between a second ligand and a molecule with a recoupled pair bond results in a recoupled pair bond dyad. We examine the recoupled pair bond dyads in the a3B1 states of CF2 and SF2, which are formed by the addition of a fluorine atom to the a4Σ- states of CF and SF, both of which possess recoupled pair bonds. The two dyads are very different. In SF2, the second FS-F bond is very strong (De = 106.3 kcal/mol), the bond length is much shorter than that in the SF(a4Σ-) state (1.666 Å versus 1.882 Å), and the three atoms are nearly collinear (θe = 162.7°) with only a small barrier to linearity (0.4 kcal/mol). In CF2, the second FC-F bond is also very strong (De = 149.5 kcal/mol), but the bond is only slightly shorter than that in the CF(a4Σ-) state (1.314 Å versus 1.327 Å), and the molecule is strongly bent (θe = 119.0°) with an 80.5 kcal/mol barrier to linearity. The a3B1 states of CF2 and SF2 illustrate the fundamental differences between recoupled pair bond dyads formed from 2s and 3p lone pairs.

  6. Intralayer-versus-interlayer pairing in the copper oxide superconductors

    SciTech Connect

    Klemm, R.A. Solid State Division, Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, Tennessee ); Liu, S.H. )

    1991-10-01

    We have investigated the competing roles of intralayer {ital s}-wave and interlayer BCS-like pairing in determining the {ital c}-axis versus {ital ab}-plane energy-gap anisotropy in layered superconductors with {ital N}=1,2 conducting planes per unit-cell edge {ital s}. For {ital N}=1, intralayer {ital s}-wave pairing leads to a conventional order parameter (OP) {Delta}{sub 0} with a transition temperature ({ital T}{sub {ital c}}) value {ital T}{sub {ital c}0} and isotropic energy gap 2{vert bar}{Delta}{sub 0}{vert bar}. For interlayer pairing, the four-vector gap function {tilde {Delta}}{sub 3}({ital k}{sub {ital z}}) contains a singlet OP {Delta}{sub {ital s}} and a vector triplet OP {Delta}{sub {ital t}}, with corresponding normalized gap functions {radical}2 cos{ital k}{sub {ital z}s} and {radical}2 sin{ital k}{sub {ital z}s}. Since {Delta}{sub {ital s}} and {Delta}{sub {ital t}} have identical {ital T}{sub {ital c}} values ({ital T}{sub {ital c}{ital s}}={ital T}{sub {ital c}{ital t}}), the free energy is minimized when {vert bar}{Delta}{sub {ital s}}{vert bar}={vert bar}{Delta}{sub {ital t}}{vert bar}, and the resulting gap 2{vert bar}{Delta}{vert bar} is found to be {ital isotropic}. However, 2{vert bar}{Delta}{vert bar} is completely {ital incompatible} with 2{vert bar}{Delta}{sub 0}{vert bar}. For {ital N}=2, there are two intralayer pairing OP's {Delta}{sub 0} and {Delta}{sub 1}, and two interlayer four-vector gap functions {tilde {Delta}}{sub 3}({ital k}{sub {ital z}}) and {tilde {Delta}}{sub 2}({ital k}{sub {ital z}}), all of which could contribute to measurable quantities in the Gaussian-fluctuation regime above the highest {ital T}{sub {ital c}} value.

  7. Nuclear level density of even-even nuclei with temperature-dependent pairing energy

    NASA Astrophysics Data System (ADS)

    Dehghani, V.; Alavi, S. A.

    2016-10-01

    The influence of using a temperature-dependent pairing term on the back-shifted Fermi gas (BSFG) model of nuclear level density of some even-even nuclei has been investigated. We have chosen an approach to determine the adjustable parameters from theoretical calculations, directly. The exact Ginzburg-Landau (EGL) theory was used to determine the temperature-dependent pairing energy as back-shifted parameter of the BSFG model. The level density parameter of the BSFG model has been determined through the Thomas-Fermi approximation. The level densities of 96Mo, 106,112Cd, 106,108Pd, 164Dy, 232Th, 238U and heat capacities of 96Mo and 164Dy nuclei were calculated. Good agreement between theory and experiment was observed.

  8. Design Considerations for a Dedicated Gravity Recovery Satellite Mission Consisting of Two Pairs of Satellites

    NASA Technical Reports Server (NTRS)

    Wiese, D. N.; Nerem, R. S.; Lemoine, F. G.

    2011-01-01

    Future satellite missions dedicated to measuring time-variable gravity will need to address the concern of temporal aliasing errors; i.e., errors due to high-frequency mass variations. These errors have been shown to be a limiting error source for future missions with improved sensors. One method of reducing them is to fly multiple satellite pairs, thus increasing the sampling frequency of the mission. While one could imagine a system architecture consisting of dozens of satellite pairs, this paper explores the more economically feasible option of optimizing the orbits of two pairs of satellites. While the search space for this problem is infinite by nature, steps have been made to reduce it via proper assumptions regarding some parameters and a large number of numerical simulations exploring appropriate ranges for other parameters. A search space originally consisting of 15 variables is reduced to two variables with the utmost impact on mission performance: the repeat period of both pairs of satellites (shown to be near-optimal when they are equal to each other), as well as the inclination of one of the satellite pairs (the other pair is assumed to be in a polar orbit). To arrive at this conclusion, we assume circular orbits, repeat groundtracks for both pairs of satellites, a 100-km inter-satellite separation distance, and a minimum allowable operational satellite altitude of 290 km based on a projected 10-year mission lifetime. Given the scientific objectives of determining time-variable hydrology, ice mass variations, and ocean bottom pressure signals with higher spatial resolution, we find that an optimal architecture consists of a polar pair of satellites coupled with a pair inclined at 72deg, both in 13-day repeating orbits. This architecture provides a 67% reduction in error over one pair of satellites, in addition to reducing the longitudinal striping to such a level that minimal post-processing is required, permitting a substantial increase in the spatial

  9. Design considerations for a dedicated gravity recovery satellite mission consisting of two pairs of satellites

    NASA Astrophysics Data System (ADS)

    Wiese, D. N.; Nerem, R. S.; Lemoine, F. G.

    2012-02-01

    Future satellite missions dedicated to measuring time-variable gravity will need to address the concern of temporal aliasing errors; i.e., errors due to high-frequency mass variations. These errors have been shown to be a limiting error source for future missions with improved sensors. One method of reducing them is to fly multiple satellite pairs, thus increasing the sampling frequency of the mission. While one could imagine a system architecture consisting of dozens of satellite pairs, this paper explores the more economically feasible option of optimizing the orbits of two pairs of satellites. While the search space for this problem is infinite by nature, steps have been made to reduce it via proper assumptions regarding some parameters and a large number of numerical simulations exploring appropriate ranges for other parameters. A search space originally consisting of 15 variables is reduced to two variables with the utmost impact on mission performance: the repeat period of both pairs of satellites (shown to be near-optimal when they are equal to each other), as well as the inclination of one of the satellite pairs (the other pair is assumed to be in a polar orbit). To arrive at this conclusion, we assume circular orbits, repeat groundtracks for both pairs of satellites, a 100-km inter-satellite separation distance, and a minimum allowable operational satellite altitude of 290 km based on a projected 10-year mission lifetime. Given the scientific objectives of determining time-variable hydrology, ice mass variations, and ocean bottom pressure signals with higher spatial resolution, we find that an optimal architecture consists of a polar pair of satellites coupled with a pair inclined at 72°, both in 13-day repeating orbits. This architecture provides a 67% reduction in error over one pair of satellites, in addition to reducing the longitudinal striping to such a level that minimal post-processing is required, permitting a substantial increase in the spatial

  10. Pair-tunneling induced localized waves in a vector nonlinear Schrödinger equation

    NASA Astrophysics Data System (ADS)

    Zhao, Li-Chen; Ling, Liming; Yang, Zhan-Ying; Liu, Jie

    2015-06-01

    We investigate localized waves of coupled two-mode nonlinear Schrödinger equations with a pair-tunneling term representing strongly interacting particles can tunnel between the modes as a fragmented pair. Facilitated by Darboux transformation, we have derived exact solution of nonlinear vector waves such as bright solitons, Kuznetsov-Ma soliton, Akhmediev breathers and rogue waves and demonstrated their interesting temporal-spatial structures. A phase diagram that demarcates the parameter ranges of the nonlinear waves is obtained. Possibilities to observe these localized waves are discussed in a two species Bose-Einstein condensate.

  11. Parameter identification for nonlinear aerodynamic systems

    NASA Technical Reports Server (NTRS)

    Pearson, Allan E.

    1990-01-01

    Parameter identification for nonlinear aerodynamic systems is examined. It is presumed that the underlying model can be arranged into an input/output (I/O) differential operator equation of a generic form. The algorithm estimation is especially efficient since the equation error can be integrated exactly given any I/O pair to obtain an algebraic function of the parameters. The algorithm for parameter identification was extended to the order determination problem for linear differential system. The degeneracy in a least squares estimate caused by feedback was addressed. A method of frequency analysis for determining the transfer function G(j omega) from transient I/O data was formulated using complex valued Fourier based modulating functions in contrast with the trigonometric modulating functions for the parameter estimation problem. A simulation result of applying the algorithm is given under noise-free conditions for a system with a low pass transfer function.

  12. Character and spatial distribution of OH/H2O on the surface of the Moon seen by M3 on Chandrayaan-1.

    PubMed

    Pieters, C M; Goswami, J N; Clark, R N; Annadurai, M; Boardman, J; Buratti, B; Combe, J-P; Dyar, M D; Green, R; Head, J W; Hibbitts, C; Hicks, M; Isaacson, P; Klima, R; Kramer, G; Kumar, S; Livo, E; Lundeen, S; Malaret, E; McCord, T; Mustard, J; Nettles, J; Petro, N; Runyon, C; Staid, M; Sunshine, J; Taylor, L A; Tompkins, S; Varanasi, P

    2009-10-23

    The search for water on the surface of the anhydrous Moon had remained an unfulfilled quest for 40 years. However, the Moon Mineralogy Mapper (M3) on Chandrayaan-1 has recently detected absorption features near 2.8 to 3.0 micrometers on the surface of the Moon. For silicate bodies, such features are typically attributed to hydroxyl- and/or water-bearing materials. On the Moon, the feature is seen as a widely distributed absorption that appears strongest at cooler high latitudes and at several fresh feldspathic craters. The general lack of correlation of this feature in sunlit M3 data with neutron spectrometer hydrogen abundance data suggests that the formation and retention of hydroxyl and water are ongoing surficial processes. Hydroxyl/water production processes may feed polar cold traps and make the lunar regolith a candidate source of volatiles for human exploration. PMID:19779151

  13. Clinical isolates of Enterobacteriaceae producing extended-spectrum beta-lactamases: prevalence of CTX-M-3 at a hospital in China.

    PubMed

    Wang, Hui; Kelkar, Swathi; Wu, Weiyuan; Chen, Minjun; Quinn, John P

    2003-02-01

    The prevalence of extended-spectrum beta-lactamase-producing strains was demonstrated in 5 of 44 (11.4%) Escherichia coli, 17 of 43 (39.5%) Klebsiella pneumoniae, 3 of 50 (6.0%) Enterobacter cloacae, and 2 of 25 (8.0%) Citrobacter freundii strains at a teaching hospital in China. Nineteen of these 27 strains expressed CTX-M-3 beta-lactamase (pI 8.6). A subset of the clinical isolates expressing the CTX-M-3 enzyme, tested by pulsed-field gel electrophoresis, revealed multiple clones. Five isolates expressed a novel enzyme, SHV-43 (pI 8.0), which had two substitutions (Leu113Phe and Thr149Ser) compared with SHV-1.

  14. Polymorphisms in Regulator of Protease B (RopB) Alter Disease Phenotype and Strain Virulence of Serotype M3 Group A Streptococcus

    PubMed Central

    Olsen, Randall J.; Laucirica, Daniel R.; Watkins, M. Ebru; Feske, Marsha L.; Garcia-Bustillos, Jesus R.; Vu, Chau; Cantu, Concepcion; Shelburne, Samuel A.; Fittipaldi, Nahuel; Kumaraswami, Muthiah; Shea, Patrick R.; Flores, Anthony R.; Beres, Stephen B.; Lovgren, Maguerite; Tyrrell, Gregory J.; Efstratiou, Androulla; Low, Donald E.; Van Beneden, Chris A.; Musser, James M.

    2012-01-01

    Whole-genome sequencing of serotype M3 group A streptococci (GAS) from oropharyngeal and invasive infections in Ontario recently showed that the gene encoding regulator of protease B (RopB) is highly polymorphic in this population. To test the hypothesis that ropB is under diversifying selective pressure among all serotype M3 GAS strains, we sequenced this gene in 1178 strains collected from different infection types, geographic regions, and time periods. The results confirmed our hypothesis and discovered a significant association between mutant ropB alleles, decreased activity of its major regulatory target SpeB, and pharyngitis. Additionally, isoallelic strains with ropB polymorphisms were significantly less virulent in a mouse model of necrotizing fasciitis. These studies provide a model strategy for applying whole-genome sequencing followed by deep single-gene sequencing to generate new insight to the rapid evolution and virulence regulation of human pathogens. PMID:22262791

  15. Character and spatial distribution of OH/H2O on the surface of the moon seen by M3 on chandrayaan-1

    USGS Publications Warehouse

    Pieters, C.M.; Goswami, J.N.; Clark, R.N.; Annadurai, M.; Boardman, J.; Buratti, B.; Combe, J.-P.; Dyar, M.D.; Green, R.; Head, J.W.; Hibbitts, C.; Hicks, M.; Isaacson, P.; Klima, R.; Kramer, G.; Kumar, S.; Livo, E.; Lundeen, S.; Malaret, E.; McCord, T.; Mustard, J.; Nettles, J.; Petro, N.; Runyon, C.; Staid, M.; Sunshine, J.; Taylor, L.A.; Tompkins, S.; Varanasi, P.

    2009-01-01

    The search for water on the surface of the anhydrous Moon had remained an unfulfilled quest for 40 years. However, the Moon Mineralogy Mapper (M 3) on Chandrayaan-1 has recently detected absorption features near 2.8 to 3.0 micrometers on the surface of the Moon. For silicate bodies, such features are typically attributed to hydroxyl- and/or water-bearing materials. On the Moon, the feature is seen as a widely distributed absorption that appears strongest at cooler high latitudes and at several fresh feldspathic craters. The general lack of correlation of this feature in sunlit M3 data with neutron spectrometer hydrogen abundance data suggests that the formation and retention of hydroxyl and water are ongoing surficial processes. Hydroxyl/water production processes may feed polar cold traps and make the lunar regolith a candidate source of volatiles for human exploration.

  16. Character and spatial distribution of OH/H2O on the surface of the Moon seen by M3 on Chandrayaan-1.

    PubMed

    Pieters, C M; Goswami, J N; Clark, R N; Annadurai, M; Boardman, J; Buratti, B; Combe, J-P; Dyar, M D; Green, R; Head, J W; Hibbitts, C; Hicks, M; Isaacson, P; Klima, R; Kramer, G; Kumar, S; Livo, E; Lundeen, S; Malaret, E; McCord, T; Mustard, J; Nettles, J; Petro, N; Runyon, C; Staid, M; Sunshine, J; Taylor, L A; Tompkins, S; Varanasi, P

    2009-10-23

    The search for water on the surface of the anhydrous Moon had remained an unfulfilled quest for 40 years. However, the Moon Mineralogy Mapper (M3) on Chandrayaan-1 has recently detected absorption features near 2.8 to 3.0 micrometers on the surface of the Moon. For silicate bodies, such features are typically attributed to hydroxyl- and/or water-bearing materials. On the Moon, the feature is seen as a widely distributed absorption that appears strongest at cooler high latitudes and at several fresh feldspathic craters. The general lack of correlation of this feature in sunlit M3 data with neutron spectrometer hydrogen abundance data suggests that the formation and retention of hydroxyl and water are ongoing surficial processes. Hydroxyl/water production processes may feed polar cold traps and make the lunar regolith a candidate source of volatiles for human exploration.

  17. RR Lyrae stars in the outer region of the globular cluster M 3: A shortage of long periods at r ˜ 3.5 to 6 arcmin?

    NASA Astrophysics Data System (ADS)

    Butler, D. J.

    2004-06-01

    An analysis of the radial distribution of ab-type RR Lyrae star periods in the outer region of the globular cluster M 3 at r ≥0.83' has been performed. That analysis points towards a real shortage of stars with long periods in the radial distance range 3.5' to 6' (or about 7 to 12 core radii). A brief discussion is presented. The origin of the phenomenon remains an open question.

  18. Comparison of Analysis Results Between 2D/1D Synthesis and RAPTOR-M3G in the Korea Standard Nuclear Plant (KSNP)

    NASA Astrophysics Data System (ADS)

    Joung Lim, Mi; Maeng, Young Jae; Fero, Arnold H.; Anderson, Stanwood L.

    2016-02-01

    The 2D/1D synthesis methodology has been used to calculate the fast neutron (E > 1.0 MeV) exposure to the beltline region of the reactor pressure vessel. This method uses the DORT 3.1 discrete ordinates code and the BUGLE-96 cross-section library based on ENDF/B-VI. RAPTOR-M3G (RApid Parallel Transport Of Radiation-Multiple 3D Geometries) which performs full 3D calculations was developed and is based on domain decomposition algorithms, where the spatial and angular domains are allocated and processed on multi-processor computer architecture. As compared to traditional single-processor applications, this approach reduces the computational load as well as the memory requirement per processor. Both methods are applied to surveillance test results for the Korea Standard Nuclear Plant (KSNP)-OPR (Optimized Power Reactor) 1000 MW. The objective of this paper is to compare the results of the KSNP surveillance program between 2D/1D synthesis and RAPTOR-M3G. Each operating KSNP has a reactor vessel surveillance program consisting of six surveillance capsules located between the core and the reactor vessel in the downcomer region near the reactor vessel wall. In addition to the In-Vessel surveillance program, an Ex-Vessel Neutron Dosimetry (EVND) program has been implemented. In order to estimate surveillance test results, cycle-specific forward transport calculations were performed by 2D/1D synthesis and by RAPTOR-M3G. The ratio between measured and calculated (M/C) reaction rates will be discussed. The current plan is to install an EVND system in all of the Korea PWRs including the new reactor type, APR (Advanced Power Reactor) 1400 MW. This work will play an important role in establishing a KSNP-specific database of surveillance test results and will employ RAPTOR-M3G for surveillance dosimetry location as well as positions in the KSNP reactor vessel.

  19. In vivo and in vitro pharmacological characterization of SVT-40776, a novel M3 muscarinic receptor antagonist, for the treatment of overactive bladder

    PubMed Central

    Salcedo, C; Davalillo, S; Cabellos, J; Lagunas, C; Balsa, D; Pérez-del-Pulgar, S; Ballarín, M; Fernández, AG

    2009-01-01

    Background and purpose: Highly selective M3 muscarinic receptor antagonists may represent a better treatment for overactive bladder syndrome, diminishing side effects. Cardiac side effects of non-selective antimuscarinics have been associated with activity at M2 receptors as these receptors are mainly responsible for muscarinic receptor-dependent bradycardia. We have investigated a novel antimuscarinic, SVT-40776, highly selective for M3 over M2 receptors (Ki = 0.19 nmol·L−1 for M3 receptor affinity). This study reports the functional activity of SVT-40776 in the bladder, relative to its activity in atria. Experimental approach: In vitro and ex vivo (oral dosing) inhibition of mouse detrusor and atrial contractile responses to carbachol were used to study the functional activity of SVT-40776. The in vivo efficacy of SVT-40776 was characterized by suppression of isovolumetric spontaneous bladder contractions in anaesthetized guinea pigs after intravenous administration. Key results: SVT-40776 was the most potent in inhibiting carbachol-induced bladder contractions of the anti-cholinergic agents tested, without affecting atrial contractions over the same range of concentrations. SVT-40776 exhibited the highest urinary versus cardiac selectivity (199-fold). In the guinea pig in vivo model, SVT-40776 inhibited 25% of spontaneous bladder contractions at a very low dose (6.97 µg·kg−1 i.v), without affecting arterial blood pressure. Conclusions and implications: SVT-40776 is a potent inhibitor of M3 receptor-related detrusor contractile activity. The absence of effects on isolated atria preparations represents an interesting characteristic and suggests that SVT-40776 may lack unwanted cardiac effects; a feature especially relevant in a compound intended to treat mainly elderly patients. British Journal of Pharmacology (2009) doi:10.1111/j.1476-5381.2008.00082.x PMID:19222482

  20. Effects of ginger constituents on the gastrointestinal tract: role of cholinergic M3 and serotonergic 5-HT3 and 5-HT4 receptors.

    PubMed

    Pertz, Heinz H; Lehmann, Jochen; Roth-Ehrang, René; Elz, Sigurd

    2011-07-01

    The herbal drug ginger (Zingiber officinale Roscoe) may be effective for treating nausea, vomiting, and gastric hypomotility. In these conditions, cholinergic M (3) receptors and serotonergic 5-HT (3) and 5-HT (4) receptors are involved. The major chemical constituents of ginger are [6]-gingerol, [8]-gingerol, [10]-gingerol, and [6]-shogaol. We studied the interaction of [6]-gingerol, [8]-gingerol, [10]-gingerol (racemates), and [6]-shogaol with guinea pig M (3) receptors, guinea pig 5-HT (3) receptors, and rat 5-HT (4) receptors. In whole segments of guinea pig ileum (bioassay for contractile M (3) receptors), [6]-gingerol, [8]-gingerol, [10]-gingerol, and [6]-shogaol slightly but significantly depressed the maximal carbachol response at an antagonist concentration of 10 µM. In the guinea pig myenteric plexus preparation (bioassay for contractile 5-HT (3) receptors), 5-HT maximal responses were depressed by [10]-gingerol from 93 ± 3 % to 65 ± 6 % at an antagonist concentration of 3 µM and to 48 ± 3 % at an antagonist concentration of 5 µM following desensitization of 5-HT (4) receptors and blockade of 5-HT (1) and 5-HT (2) receptors. [6]-Shogaol (3 µM) induced depression to 61 ± 3 %. In rat esophageal tunica muscularis mucosae (bioassay for relaxant 5-HT (4) receptors), [6]-gingerol, [8]-gingerol, [10]-gingerol, and [6]-shogaol (2-6.3 µM) showed no agonist effects. The maximal 5-HT response remained unaffected in the presence of the compounds. It is concluded that the efficiency of ginger in reducing nausea and vomiting may be based on a weak inhibitory effect of gingerols and shogaols at M (3) and 5-HT (3) receptors. 5-HT (4) receptors, which play a role in gastroduodenal motility, appear not to be involved in the action of these compounds. PMID:21305447

  1. Sources and physical processes responsible for OH/H2O in the lunar soil as revealed by the Moon Mineralogy Mapper (M3)

    USGS Publications Warehouse

    McCord, T.B.; Taylor, L.A.; Combe, J.-P.; Kramer, G.; Pieters, C.M.; Sunshine, J.M.; Clark, R.N.

    2011-01-01

    Analysis of two absorption features near 3 m in the lunar reflectance spectrum, observed by the orbiting M3 spectrometer and interpreted as being due to OH and H2O, is presented, and the results are used to discuss the processes producing these molecules. This analysis focuses on the dependence of the absorptions on lunar physical properties, including composition, illumination, latitude, and temperature. Solar wind proton-induced hydroxylation is proposed as the creation process, and its products could be a source for other reported types of hydrogen-rich material and water. The irregular and damaged fine-grained lunar soil seems especially adapted for trapping solar wind protons and forming OH owing to abundant dangling oxygen bonds. The M3 data reveal that the strengths of the two absorptions are correlated and widespread, and both are correlated with lunar composition but in different ways. Feldspathic material seems richer in OH. These results seem to rule out water from the lunar interior and cometary infall as major sources. There appear to be correlations of apparent band strengths with time of day and lighting conditions. However, thermal emission from the Moon reduces the apparent strengths of the M3 absorptions, and its removal is not yet completely successful. Further, many of the lunar physical properties are themselves intercorrelated, and so separating these dependencies on the absorptions is difficult, due to the incomplete M3 data set. This process should also operate on other airless silicate surfaces, such as Mercury and Vesta, which will be visited by the Dawn spacecraft in mid-2011. Copyright 2011 by the American Geophysical Union.

  2. Activation of muscarinic M3 receptors inhibits large-conductance voltage- and Ca2+-activated K+ channels in rat urinary bladder smooth muscle cells

    PubMed Central

    Parajuli, Shankar P.

    2013-01-01

    Large conductance voltage- and Ca2+-activated K+ (BK) channels are key regulators of detrusor smooth muscle (DSM) contraction and relaxation during urine voiding and storage. Here, we explored whether BK channels are regulated by muscarinic receptors (M-Rs) in native freshly isolated rat DSM cells under physiological conditions using the perforated whole cell patch-clamp technique and pharmacological inhibitors. M-R activation with carbachol (1 μM) initially evoked large transient outward BK currents, followed by inhibition of the spontaneous transient outward BK currents (STBKCs) in DSM cells. Carbachol (1 μM) also inhibited the amplitude and frequency of spontaneous transient hyperpolarizations (STHs) and depolarized the DSM cell membrane potential. Selective inhibition of the muscarinic M3 receptors (M3-Rs) with 4-diphenylacetoxy-N-methylpiperidine (4-DAMP; 0.1 μM), but not muscarinic M2 receptors with methoctramine (1 μM), blocked the carbachol inhibitory effects on STBKCs. Furthermore, blocking the inositol 1,4,5-triphosphate (IP3) receptors with xestospongin-C (1 μM) inhibited the carbachol-induced large transient outward BK currents without affecting carbachol inhibitory effects on STBKCs. Upon pharmacological inhibition of all known cellular sources of Ca2+ for BK channel activation, carbachol (1 μM) did not affect the voltage-step-induced steady-state BK currents, suggesting that the muscarinic effects in DSM cells are mediated by mobilization of intracellular Ca2+. In conclusion, our findings provide strong evidence that activation of M3-Rs leads to inhibition of the STBKCs, STHs, and depolarization of DSM cells. Collectively, the data suggest the existence of functional interactions between BK channels and M3-Rs at a cellular level in DSM. PMID:23703523

  3. Ferroelectric and magnetic properties of Aurivillius Bi{sub m+1}Ti{sub 3}Fe{sub m−3}O{sub 3m+3} thin films

    SciTech Connect

    Jia, Tingting Kimura, Hideo; Cheng, Zhenxiang; Zhao, Hongyang

    2015-11-15

    Aurivillius Bi{sub m+1}Ti{sub 3}Fe{sub m−3}O{sub 3m+3} (m = 4, 5, 6) thin films have been deposited by a pulsed laser deposition system. The x-ray diffraction patterns indicate the formation of orthorhombic phase. The remanent polarization (2P{sub r}) of Bi{sub m+1}Ti{sub 3}Fe{sub m−3}O{sub 3m+3} thin films is decreased with the m-number. Positive-up-negative-down measurements indicate the presence of ferroelectric (FE) polarization in as-obtained thin films. Piezoresponse force microscopy investigations confirm the existence of FE domains and the switchable polarization. Weak magnetic moment is detected in the Aurivillius films at room temperature. The present work suggests the possibility of Aurivillius Bi{sub m+1}Ti{sub 3}Fe{sub m−3}O{sub 3m+3} (m = 4, 5, 6) materials as potential room-temperature multiferroics.

  4. Sleep as spatiotemporal integration of biological processes that evolved to periodically reinforce neurodynamic and metabolic homeostasis: The 2m3d paradigm of sleep.

    PubMed

    Mader, Edward Claro; Mader, Annie Cielo Llave

    2016-08-15

    Sleep continues to perplex scientists and researchers. Despite decades of sleep research, we still lack a clear understanding of the biological functions and evolution of sleep. In this review, we will examine sleep from a functional and phylogenetic perspective and describe some important conceptual gaps in understanding sleep. Classical theories of the biology and evolution of sleep emphasize sensory activation, energy balance, and metabolic homeostasis. Advances in electrophysiology, functional neuroimaging, and neuroplasticity allow us to view sleep within the framework of neural dynamics. With this paradigm shift, we have come to realize the importance of neurodynamic homeostasis in shaping the biology of sleep. Evidently, animals sleep to achieve neurodynamic and metabolic homeostasis. We are not aware of any framework for understanding sleep where neurodynamic, metabolic, homeostatic, chronophasic, and afferent variables are all taken into account. This motivated us to propose the two-mode three-drive (2m3d) paradigm of sleep. In the 2m3d paradigm, local neurodynamic/metabolic (N/M) processes switch between two modes-m0 and m1-in response to three drives-afferent, chronophasic, and homeostatic. The spatiotemporal integration of local m0/m1 operations gives rise to the global states of sleep and wakefulness. As a framework of evolution, the 2m3d paradigm allows us to view sleep as a robust adaptive strategy that evolved so animals can periodically reinforce neurodynamic and metabolic homeostasis while remaining sensitive to their internal and external environment.

  5. Reclamation of the wastewater from an industrial park using hollow-fibre and spiral-wound membranes: 50 m3 d(-1) pilot testing and cost evaluation.

    PubMed

    Chu, C P; Jiaoa, S R; Hung, J M; Lu, C J; Chung, Y J

    2009-08-01

    The feasibility of reclaiming effluent from industrial park wastewater treatment plants through a membrane process was evaluated in three phases. In phase 1 we selected nine wastewater treatment plants (WWTPs), each with a design capacity exceeding 10,000 m3 d(-1), and analyzed the corresponding effluent composition. 'Potential recycling percentage', R, ranged from 50% to 80% for the industrial park WWTPs, indicating a high feasibility for the reuse of effluent. In phase 2, a 50 m3 d(-1) pilot plant was installed in one of the selected WWTPs and underwent testing for one year. The quality of the reclaimed water was suitable for general-purpose industrial use. In the two ultrafiltration (UF) modules tested, the hydrophilic polyethersulfone hollow-fibre module was more tolerant to variable properties, and had higher recycling percentages than those of backwashable hydrophobic polyvinylidene difluoride spiral-wound module. Using the spiral-wound UF module helped reduce the cost for producing 1 m3 of reclaimed water (US$0.80) compared with a hollow-fibre module (US$0.88). In phase 3, we evaluated the negative effects of refluxing the reverse osmosis retentate, containing high total dissolved solids and non-biodegradable organics, with the biological treatment unit of the upstream WWTP. Biological compactibility tests showed that the refluxed retentate ratio should be reduced to maintain the conductivity of mixed liquor in the aeration tank at less than 110% of the original value.

  6. Controlling the transmitted information of a multi-photon interacting with a single-Cooper pair box

    SciTech Connect

    Kadry, Heba Abdel-Aty, Abdel-Haleem Zakaria, Nordin; Cheong, Lee Yen

    2014-10-24

    We study a model of a multi-photon interaction of a single Cooper pair box with a cavity field. The exchange of the information using this system is studied. We quantify the fidelity of the transmitted information. The effect of the system parameters (detuning parameter, field photons, state density and mean photon number) in the fidelity of the transmitted information is investigated. We found that the fidelity of the transmitted information can be controlled using the system parameters.

  7. Long-term pair bonds in the Laysan Duck

    USGS Publications Warehouse

    Reynolds, M.H.; Breeden, J.H.; Vekasy, M.S.; Ellis, T.M.

    2009-01-01

    We describe long-term pair bonds in the endangered Laysan Duck (Anas laysanensis), a dabbling duck endemic to the Hawaiian Archipelago. Individually marked birds were identified on Laysan Island between 1998 and 2006 (n = 613 marked adults). We recorded pair bonds while observing marked birds, and documented within and between year mate switches and multi-year pair bonds. Twenty pairs banded before 2001 had stable pair bonds lasting ???5 years with a maximum enduring pair bond of nine breeding seasons. Understanding reproductive strategy, including mate retention, would aid conservation planning and management efforts for the Laysan Duck. Further study is needed to characterize the social system of this endangered species.

  8. Redefining solubility parameters: the partial solvation parameters.

    PubMed

    Panayiotou, Costas

    2012-03-21

    The present work reconsiders a classical and universally accepted concept of physical chemistry, the solubility parameter. Based on the insight derived from modern quantum chemical calculations, a new definition of solubility parameter is proposed, which overcomes some of the inherent restrictions of the original definition and expands its range of applications. The original single solubility parameter is replaced by four partial solvation parameters reflecting the dispersion, the polar, the acidic and the basic character of the chemical compounds as expressed either in their pure state or in mixtures. Simple rules are adopted for the definition and calculation of these four parameters and their values are tabulated for a variety of common substances. In contrast, however, to the well known Hansen solubility parameters, their design and evaluation does not rely exclusively on the basic rule of "similarity matching" for solubility but it makes also use of the other basic rule of compatibility, namely, the rule of "complementarity matching". This complementarity matching becomes particularly operational with the sound definition of the acidic and basic components of the solvation parameter based on the third σ-moments of the screening charge distributions of the quantum mechanics-based COSMO-RS theory. The new definitions are made in a simple and straightforward manner, thus, preserving the strength and appeal of solubility parameter stemming from its simplicity. The new predictive method has been applied to a variety of solubility data for systems of pharmaceuticals and polymers. The results from quantum mechanics calculations are critically compared with the results from Abraham's acid/base descriptors. PMID:22327537

  9. Redefining solubility parameters: the partial solvation parameters.

    PubMed

    Panayiotou, Costas

    2012-03-21

    The present work reconsiders a classical and universally accepted concept of physical chemistry, the solubility parameter. Based on the insight derived from modern quantum chemical calculations, a new definition of solubility parameter is proposed, which overcomes some of the inherent restrictions of the original definition and expands its range of applications. The original single solubility parameter is replaced by four partial solvation parameters reflecting the dispersion, the polar, the acidic and the basic character of the chemical compounds as expressed either in their pure state or in mixtures. Simple rules are adopted for the definition and calculation of these four parameters and their values are tabulated for a variety of common substances. In contrast, however, to the well known Hansen solubility parameters, their design and evaluation does not rely exclusively on the basic rule of "similarity matching" for solubility but it makes also use of the other basic rule of compatibility, namely, the rule of "complementarity matching". This complementarity matching becomes particularly operational with the sound definition of the acidic and basic components of the solvation parameter based on the third σ-moments of the screening charge distributions of the quantum mechanics-based COSMO-RS theory. The new definitions are made in a simple and straightforward manner, thus, preserving the strength and appeal of solubility parameter stemming from its simplicity. The new predictive method has been applied to a variety of solubility data for systems of pharmaceuticals and polymers. The results from quantum mechanics calculations are critically compared with the results from Abraham's acid/base descriptors.

  10. Transition from Sign-Reversed to Sign-Preserved Cooper-Pairing Symmetry in Sulfur-Doped Iron Selenide Superconductors

    NASA Astrophysics Data System (ADS)

    Wang, Qisi; Park, J. T.; Feng, Yu; Shen, Yao; Hao, Yiqing; Pan, Bingying; Lynn, J. W.; Ivanov, A.; Chi, Songxue; Matsuda, M.; Cao, Huibo; Birgeneau, R. J.; Efremov, D. V.; Zhao, Jun

    2016-05-01

    An essential step toward elucidating the mechanism of superconductivity is to determine the sign or phase of the superconducting order parameter, as it is closely related to the pairing interaction. In conventional superconductors, the electron-phonon interaction induces attraction between electrons near the Fermi energy and results in a sign-preserved s -wave pairing. For high-temperature superconductors, including cuprates and iron-based superconductors, prevalent weak coupling theories suggest that the electron pairing is mediated by spin fluctuations which lead to repulsive interactions, and therefore that a sign-reversed pairing with an s± or d -wave symmetry is favored. Here, by using magnetic neutron scattering, a phase sensitive probe of the superconducting gap, we report the observation of a transition from the sign-reversed to sign-preserved Cooper-pairing symmetry with insignificant changes in Tc in the S-doped iron selenide superconductors KxFe2 -y(Se1-zSz) 2 . We show that a rather sharp magnetic resonant mode well below the superconducting gap (2 Δ ) in the undoped sample (z =0 ) is replaced by a broad hump structure above 2 Δ under 50% S doping. These results cannot be readily explained by simple spin fluctuation-exchange pairing theories and, therefore, multiple pairing channels are required to describe superconductivity in this system. Our findings may also yield a simple explanation for the sometimes contradictory data on the sign of the superconducting order parameter in iron-based materials.

  11. Augmenting Think-Pair-Share with Simulations

    NASA Astrophysics Data System (ADS)

    Lee, Kevin M.; Siedell, C. M.; Prather, E. E.; CATS

    2009-01-01

    Computer simulations are valuable tools for the teaching and learning of introductory astronomy. They enable students to link together small pieces of information into mental models of complex physical systems that are far beyond their everyday experience. They can also be used to authentically test a student's conceptual understanding of a physical system by asking the student to make predictions regarding its behavior. Students receive formative feedback by testing their predictions in simulations. Think-Pair-Share - the posing of conceptual questions to students and having them vote on the answer before and after discussion with their peers - can benefit considerably from the incorporation of simulations. Simulations can be used for delivering content that precedes Think-Pair-Share, as the prompt the questions is based upon, or as a feedback tool to illustrate the answer to a question. These techniques are utilized in ClassAction - a collection of materials designed to enhance the metacognitive skills of Astro 101 students by promoting interactive engagement and providing rapid feedback. The main focus is dynamic conceptual questions largely based upon graphics that can be projected in the classroom. Many questions are available in a Flash computer database and instructors have the capability to recast these questions into alternate permutations based on their own preferences and student responses. Outlines, graphics, and simulations are included which instructors can use to provide feedback. This poster provides examples of simulation usage in Think-Pair-Share related to sky motions, lunar phases, and stellar properties. A multi-institutional classroom validation study of ClassAction is currently underway as a Collaboration of Astronomy Teaching Scholars (CATS) research project. All materials are publicly available at http://astro.unl.edu. We would like to thank the NSF for funding under Grant Nos. 0404988 and 0715517, a CCLI Phase III Grant for the

  12. Older Galaxy Pair Has Surprisingly Youthful Glow

    NASA Technical Reports Server (NTRS)

    2007-01-01

    [figure removed for brevity, see original site] Poster Version

    A pair of interacting galaxies might be experiencing the galactic equivalent of a mid-life crisis. For some reason, the pair, called Arp 82, didn't make their stars early on as is typical of most galaxies. Instead, they got a second wind later in life -- about 2 billion years ago -- and started pumping out waves of new stars as if they were young again.

    Arp 82 is an interacting pair of galaxies with a strong bridge and a long tail. NGC 2535 is the big galaxy and NGC 2536 is its smaller companion. The disk of the main galaxy looks like an eye, with a bright 'pupil' in the center and oval-shaped 'eyelids.' Dramatic 'beads on a string' features are visible as chains of evenly spaced star-formation complexes along the eyelids. These are presumably the result of large-scale gaseous shocks from a grazing encounter. The colors of this galaxy indicate that the observed stars are young to intermediate in age, around 2 million to 2 billion years old, much less than the age of the universe (13.7 billion years).

    The puzzle is: why didn't Arp 82 form many stars earlier, like most galaxies of that mass range? Scientifically, it is an oddball and provides a relatively nearby lab for studying the age of intermediate-mass galaxies.

    This picture is a composite captured by Spitzer's infrared array camera with light at wavelength 8 microns shown in red, NASA's Galaxy Evolution Explorer combined 1530 and 2310 Angstroms shown in blue, and the Southeastern Association for Research in Astronomy Observatory light at 6940 Angstroms shown in green.

  13. Series-Coupled Pairs of Silica Microresonators

    NASA Technical Reports Server (NTRS)

    Savchenkov, Anatoliy; Iltchenko, Vladimir; Maleki, Lute; Handley, Tim

    2009-01-01

    Series-coupled pairs of whispering-gallery-mode optical microresonators have been demonstrated as prototypes of stable, narrow-band-pass photonic filters. Characteristics that are generally considered desirable in a photonic or other narrow-band-pass filter include response as nearly flat as possible across the pass band, sharp roll-off, and high rejection of signals outside the pass band. A single microresonator exhibits a Lorentzian filter function: its peak response cannot be made flatter and its roll-off cannot be made sharper. However, as a matter of basic principle applicable to resonators in general, it is possible to (1) use multiple resonators, operating in series or parallel, to obtain a roll-off sharper, and out-of-band rejection greater, relative to those of a Lorentzian filter function and (2) to make the peak response (the response within the pass band) flatter by tuning the resonators to slightly different resonance frequencies that span the pass band. The first of the two microresonators in each series-coupled pair was a microtorus made of germania-doped silica (containing about 19 mole percent germania), which is a material used for the cores of some optical fibers. The reasons for choosing this material is that exposing it to ultraviolet light causes it to undergo a chemical change that changes its index of refraction and thereby changes the resonance frequency. Hence, this material affords the means to effect the desired slight relative detuning of the two resonators. The second microresonator in each pair was a microsphere of pure silica. The advantage of making one of the resonators a torus instead of a sphere is that its spectrum of whispering-gallery-mode resonances is sparser, as needed to obtain a frequency separation of at least 100 GHz between resonances of the filter as a whole.

  14. Analysis of the behavior of the 3-µm absorptions in the M3 lunar reflectance observations and indications of OH sources and processes for airless bodies

    NASA Astrophysics Data System (ADS)

    McCord, T. B.; Combe, J.

    2010-12-01

    Absorptions in the 3-µm region of the lunar reflectance spectrum acquired by the Chandrayaan-1 Moon Mineralogy Mapper (M3) visual-IR imaging spectrometer were interpreted as indicating OH and H2O in the lunar soil (Pieters et al., 2009). Analysis of the dependence of these absorptions on the physical properties of the surface (i.e., temperature, composition, lighting geometry, latitude) was first reported by Pieters et al. (2009) and subsequently expanded (McCord et al., 2010). These dependences could be important in understanding the sources and processes concerning the OH and related molecules. A favored process is hydroxylation cause by solar wind proton implantation, and the behavior of the absorptions is consistent with this hypothesis, as will be presented. However, the incomplete M3 data set (contact was lost with the spacecraft prematurely) and removal of thermal emission (affects estimates of absorption strengths) are major complications. Thermal information from other sources, such as the Lunar Reconnaissance Orbiter (LRO) Diviner measurements (Paige et al., 2010) and subsequent models, and better knowledge of surface topography are aiding our analysis of the 3-µm absorptions strength and behavior with lunar conditions, as will be reported. More detailed investigation will help determine whether all the spectral features related to hydration are due to surficial processes only. Characterization of the formation, distribution and variations of OH and H2O on the Moon is key to understand interactions of any airless body’s surface with the space environment. Indeed, this study is also relevant for the preparation of orbital observations of the surface of Vesta by the Visible and Infrared (VIR) imaging spectrometer onboard the Dawn spacecraft (Russell et al., 2007) that will begin in summer 2011. References Pieters, C. M. and the M3 team (2009), Character and spatial distribution of OH/H2O on the surface of the Moon seen by M3 on Chandrayaan-1, Science

  15. Differential Effects of the Gβ5-RGS7 Complex on Muscarinic M3 Receptor–Induced Ca2+ Influx and Release

    PubMed Central

    Karpinsky-Semper, Darla; Volmar, Claude-Henry; Brothers, Shaun P.

    2014-01-01

    The G protein β subunit Gβ5 uniquely forms heterodimers with R7 family regulators of G protein signaling (RGS) proteins (RGS6, RGS7, RGS9, and RGS11) instead of Gγ. Although the Gβ5-RGS7 complex attenuates Ca2+ signaling mediated by the muscarinic M3 receptor (M3R), the route of Ca2+ entry (i.e., release from intracellular stores and/or influx across the plasma membrane) is unknown. Here, we show that, in addition to suppressing carbachol-stimulated Ca2+ release, Gβ5-RGS7 enhanced Ca2+ influx. This novel effect of Gβ5-RGS7 was blocked by nifedipine and 2-aminoethoxydiphenyl borate. Experiments with pertussis toxin, an RGS domain–deficient mutant of RGS7, and UBO-QIC {L-threonine,(3R)-N-acetyl-3-hydroxy-L-leucyl-(aR)-a-hydroxybenzenepropanoyl-2,3-idehydro-N-methylalanyl-L-alanyl-N-methyl-L-alanyl-(3R)-3-[[(2S,3R)-3-hydroxy-4- methyl-1-oxo-2-[(1-oxopropyl)amino]pentyl]oxy]-L-leucyl-N,O-dimethyl-,(7→1)-lactone (9CI)}, a novel inhibitor of Gq, showed that Gβ5-RGS7 modulated a Gq-mediated pathway. These studies indicate that Gβ5-RGS7, independent of RGS7 GTPase-accelerating protein activity, couples M3R to a nifedipine-sensitive Ca2+ channel. We also compared the action of Gβ5-RGS7 on M3R-induced Ca2+ influx and release elicited by different muscarinic agonists. Responses to Oxo-M [oxotremorine methiodide N,N,N,-trimethyl-4-(2-oxo-1-pyrrolidinyl)-2-butyn-1-ammonium iodide] were insensitive to Gβ5-RGS7. Pilocarpine responses consisted of a large release and modest influx components, of which the former was strongly inhibited whereas the latter was insensitive to Gβ5-RGS7. McN-A-343 [(4-hydroxy-2-butynyl)-1-trimethylammonium-3-chlorocarbanilate chloride] was the only compound whose total Ca2+ response was enhanced by Gβ5-RGS7, attributed to, in part, by the relatively small Ca2+ release this partial agonist stimulated. Together, these results show that distinct agonists not only have differential M3R functional selectivity, but also confer specific

  16. A biometric signcryption scheme without bilinear pairing

    NASA Astrophysics Data System (ADS)

    Wang, Mingwen; Ren, Zhiyuan; Cai, Jun; Zheng, Wentao

    2013-03-01

    How to apply the entropy in biometrics into the encryption and remote authentication schemes to simplify the management of keys is a hot research area. Utilizing Dodis's fuzzy extractor method and Liu's original signcryption scheme, a biometric identity based signcryption scheme is proposed in this paper. The proposed scheme is more efficient than most of the previous proposed biometric signcryption schemes for that it does not need bilinear pairing computation and modular exponentiation computation which is time consuming largely. The analysis results show that under the CDH and DL hard problem assumption, the proposed scheme has the features of confidentiality and unforgeability simultaneously.

  17. A Guide to Fluorescent Protein FRET Pairs.

    PubMed

    Bajar, Bryce T; Wang, Emily S; Zhang, Shu; Lin, Michael Z; Chu, Jun

    2016-01-01

    Förster or fluorescence resonance energy transfer (FRET) technology and genetically encoded FRET biosensors provide a powerful tool for visualizing signaling molecules in live cells with high spatiotemporal resolution. Fluorescent proteins (FPs) are most commonly used as both donor and acceptor fluorophores in FRET biosensors, especially since FPs are genetically encodable and live-cell compatible. In this review, we will provide an overview of methods to measure FRET changes in biological contexts, discuss the palette of FP FRET pairs developed and their relative strengths and weaknesses, and note important factors to consider when using FPs for FRET studies.

  18. A Guide to Fluorescent Protein FRET Pairs

    PubMed Central

    Bajar, Bryce T.; Wang, Emily S.; Zhang, Shu; Lin, Michael Z.; Chu, Jun

    2016-01-01

    Förster or fluorescence resonance energy transfer (FRET) technology and genetically encoded FRET biosensors provide a powerful tool for visualizing signaling molecules in live cells with high spatiotemporal resolution. Fluorescent proteins (FPs) are most commonly used as both donor and acceptor fluorophores in FRET biosensors, especially since FPs are genetically encodable and live-cell compatible. In this review, we will provide an overview of methods to measure FRET changes in biological contexts, discuss the palette of FP FRET pairs developed and their relative strengths and weaknesses, and note important factors to consider when using FPs for FRET studies. PMID:27649177

  19. A Guide to Fluorescent Protein FRET Pairs.

    PubMed

    Bajar, Bryce T; Wang, Emily S; Zhang, Shu; Lin, Michael Z; Chu, Jun

    2016-01-01

    Förster or fluorescence resonance energy transfer (FRET) technology and genetically encoded FRET biosensors provide a powerful tool for visualizing signaling molecules in live cells with high spatiotemporal resolution. Fluorescent proteins (FPs) are most commonly used as both donor and acceptor fluorophores in FRET biosensors, especially since FPs are genetically encodable and live-cell compatible. In this review, we will provide an overview of methods to measure FRET changes in biological contexts, discuss the palette of FP FRET pairs developed and their relative strengths and weaknesses, and note important factors to consider when using FPs for FRET studies. PMID:27649177

  20. Generalized magnetofluid connections in pair plasmas

    NASA Astrophysics Data System (ADS)

    Asenjo, Felipe A.; Comisso, Luca; Mahajan, Swadesh M.

    2015-12-01

    We extend the magnetic connection theorem of ideal magnetohydrodynamics to nonideal relativistic pair plasmas. Adopting a generalized Ohm's law, we prove the existence of generalized magnetofluid connections that are preserved by the plasma dynamics. We show that these connections are related to a general antisymmetric tensor that unifies the electromagnetic and fluid fields. The generalized magnetofluid connections set important constraints on the plasma dynamics by forbidding transitions between configurations with different magnetofluid connectivity. An approximated solution is explicitly shown where the corrections due to current inertial effects are found.