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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. Double-Mode RR LYRAE (RRd) Variables and a Blended RR LYRAE Pair in the Globular Cluster M3

    NASA Astrophysics Data System (ADS)

    Corwin, T. M.; Carney, B. W.

    1997-12-01

    Light curves are presented for the M3 variables V4, V68, V79, V87, V99, and V166, based on 183 CCD B images. The data were taken in 1992 and 1993 on the Kitt Peak 0.9-m telescope. V68 and V87 have long been known as double-mode pulsators, V79 has been recently identified as a double-mode pulsator (Clement et al. 1997), and V99 and V166 are identified here as double-mode pulsators. V4 has been previously identified as a blended RR Lyrae pair. The light curve of V4 is reproduced here by the sum of two RRab light curves of slightly different periods and different amplitudes. Clement C., Hilditch, R., Kaluzny, J., and Rucinski, S. 1997, ApJ, 489L, 55.

  4. Cultivation of Candida sp. LEB-M3 in glycerol: lipid accumulation and prediction of biodiesel quality parameters.

    PubMed

    Duarte, Susan Hartwig; Ansolin, Marina; Maugeri, Francisco

    2014-06-01

    The quality of biodiesel from lipids produced by the yeast Candida sp. LEB-M3 was predicted, by the use of mathematical models for parameters that specify quality as a function of the fatty acid profile. The lipid production was studied according to the experimental design methodology, for different cultivation conditions for agitation and aeration. Lipid compositions were affected by the cultivation conditions, and the agitation presented a positive effect for the formation of monounsaturated fatty acids and negative effect for saturated fatty acids. Aeration had a positive effect on the formation of polyunsaturated fatty acids. According to the predictions by the mathematical models, the cetane number varied from 61 to 67, the oxidative stability from 11 to 17h, the iodine index from 55 to 75gI2/100g, density from 852 to 868kg/m(3). All cultivation conditions led to lipid compositions, whose predicted bioparameter values indicate that biodiesel from this lipid source should present current standard quality. PMID:24732707

  5. Nearest-neighbor parameters for 7-deaza-adenosine·uridine base pairs in RNA duplexes.

    PubMed

    Richardson, Katherine E; Znosko, Brent M

    2016-06-01

    One of the major limitations in RNA structure prediction is the lack of information about the effect of nonstandard nucleotides on stability. The nonstandard nucleotide 7-deaza-adenosine (7DA) is a naturally occurring analog of adenosine that has been studied for medicinal purposes and is commonly referred to as tubercidin. In 7DA, the nitrogen in the 7 position of adenosine is replaced by a carbon. Differences in RNA duplex stability due to the removal of this nitrogen can be attributed to a possible change in hydration and a difference in base stacking interactions resulting from changes in the electrostatics of the ring. In order to determine how 7DA affects the stability of RNA, optical melting experiments were conducted on RNA duplexes that contain either internal or terminal 7DA·U pairs with all possible nearest-neighbor combinations. On average, duplexes containing 7DA·U pairs are 0.43 and 0.07 kcal/mol less stable than what is predicted for the same duplex containing internal and terminal A-U pairs, respectively. Thermodynamic parameters for all nearest-neighbor combinations of 7DA·U pairs were derived from the data. These parameters can be used to more accurately predict the secondary structure and stability of RNA duplexes containing 7DA·U pairs. PMID:27099368

  6. 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.

  7. Effect of Short-Term Pair Housing of Juvenile Rhesus Macaques (Macaca mulatta) on Immunologic Parameters

    PubMed Central

    Benton, Carrie G; West, Michael W; Hall, Shane M; Marko, Shannon T; Johnson, Joshua C

    2013-01-01

    Social housing of nonhuman primates (NHP) in an infectious disease setting presents unique challenges, and individual housing is often scientifically justified. At our institute, we recognized an opportunity to limit individual housing to the minimal period necessary by pair-housing NHP after quarantine and separating them just before they are moved into holding rooms for infectious disease studies. To alleviate concerns that pair-housing followed by separation affects the immune system of NHP and makes them unfit as research candidates, we designed a short-term pair-housing study. After a 3-wk baseline period, juvenile rhesus macaques (age, 3 to 4 y) were paired for 7 wk and then separated for 7 wk. During the study, serum cortisol, lymphocyte subsets, and proinflammatory cytokines were measured. The average values for all parameters were significantly lower after separation than during the baseline period. We conclude that short-term pair housing is a viable option at our institute for social housing of NHP. PMID:23849405

  8. Segregation parameters and pair-exchange mixing models for turbulent nonpremixed flames

    NASA Technical Reports Server (NTRS)

    Chen, J.-Y.; Kollman, W.

    1991-01-01

    The progress of chemical reactions in nonpremixed turbulent flows depends on the coexistence of reactants, which are brought together by mixing. The degree of mixing can strongly influence the chemical reactions and it can be quantified by segregation parameters. In this paper, the relevance of segregation parameters to turbulent mixing and chemical reactions is explored. An analysis of the pair-exchange mixing models is performed and an explanation is given for the peculiar behavior of such models in homogeneous turbulence. The nature of segregation parameters in a H2/Ar-air nonpremixed jet flame is investigated. The results show that Monte Carlo simulation with the modified Curl's mixing model predicts segregation parameters in close agreement with the experimental values, providing an indirect validation for the theoretical model.

  9. 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).

  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. Measurement of wheel pair parameters of a rolling stock during movement

    NASA Astrophysics Data System (ADS)

    Venediktov, Anatoli Z.; Demkin, Vladimir N.; Dokov, Dmitri S.; Tireshkin, V. N.

    2003-06-01

    In work is considered the problem arising at measurement of wheel pairs parameters during the movement of a train, owing to the complex form and a brilliant surface of a rim of a wheel. The submitted device allows to expand essentially a dynamic range of a photo camera with CCD image sensor. Comparative characteristics of gauges with a feedback on intensity are given. The design of the guage and a function chart of measuring system are described on the basis of these gauges. Application of a contactless optical method of a laser triangulation is most perspective for measurement of the geometrical sizes of wheel pairs on the moving train. Its application will allow to reduce time of the control and to raise safety of transportations.

  12. Pairing and coherence order parameters in a three-component ultracold Fermi gas

    SciTech Connect

    Chung, Chun Kit; Law, C. K.

    2010-09-15

    We investigate the mean-field ground state of a homogeneous three-component attractive Fermi gas at zero temperature. This is achieved by deriving a set of Bogoliubov-de Gennes (BdG) equations of the three-component system, including pairing both order parameters {Delta}{sub ij} and coherence order parameters <{psi}{sub i}{sup {dagger}{psi}}{sub j}> (i{ne}j), where {psi}{sub j} is the field operator for spin level j. Ward-Takahashi identities are obtained to constrain these order parameters. In addition, we present an explicit analytic mean-field solution for symmetric systems and verify that the quasiparticle excitations consist of both gapped and gapless spectra, which correspond to the excitations of paired and unpaired atoms. We further point out that the omission of <{psi}{sub i}{sup {dagger}{psi}}{sub j}> in BdG equations could lead to an overestimation of {Delta}{sub ij} in the strong coupling regime.

  13. 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.

  14. 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.

  15. 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.

  16. Relationship between pairing symmetries and interaction parameters in iron-based superconductors from functional renormalization group calculations

    NASA Astrophysics Data System (ADS)

    Yuan, Jing; Hu, Jiangping

    2016-03-01

    Pairing symmetries of iron-based superconductors are investigated systematically in a five-orbital model within the different regions of interaction parameters by functional renormalization group (FRG). Even for a fixed Fermi surface with both hole and electron pockets, it is found that depending on interaction parameters, a variety of pairing symmetries, including two types of d-wave and two types of s-wave pairing symmetries, can emerge. Only the dx^2-y^2 - and the s±-waves are robustly supported by the nearest-neighbor (NN) intra-orbital J 1 and the next-nearest-neighbor (NNN) intra-orbital J 2 antiferromagnetic (AFM) exchange couplings, respectively. This study suggests that the accurate initial input of the interaction parameters is essential to make FRG a useful method to determine the leading channel of superconducting instability.

  17. 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.

  18. Calibration and data collection protocols for reliable lattice parameter values in electron pair distribution function studies

    SciTech Connect

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

    2015-01-30

    Different protocols for calibrating electron pair distribution function (ePDF) measurements are explored and described for quantitative studies on nanomaterials. It is found that the most accurate approach to determine the camera length is to use a standard calibration sample of Au nanoparticles from the 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.

  19. 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.

  20. 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

  1. 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

  2. PuFFIN - a parameter-free method to build nucleosome maps from paired-end reads

    PubMed Central

    2014-01-01

    Background We introduce a novel method, called PuFFIN, that takes advantage of paired-end short reads to build genome-wide nucleosome maps with larger numbers of detected nucleosomes and higher accuracy than existing tools. In contrast to other approaches that require users to optimize several parameters according to their data (e.g., the maximum allowed nucleosome overlap or legal ranges for the fragment sizes) our algorithm can accurately determine a genome-wide set of non-overlapping nucleosomes without any user-defined parameter. This feature makes PuFFIN significantly easier to use and prevents users from choosing the "wrong" parameters and obtain sub-optimal nucleosome maps. Results PuFFIN builds genome-wide nucleosome maps using a multi-scale (or multi-resolution) approach. Our algorithm relies on a set of nucleosome "landscape" functions at different resolution levels: each function represents the likelihood of each genomic location to be occupied by a nucleosome for a particular value of the smoothing parameter. After a set of candidate nucleosomes is computed for each function, PuFFIN produces a consensus set that satisfies non-overlapping constraints and maximizes the number of nucleosomes. Conclusions We report comprehensive experimental results that compares PuFFIN with recently published tools (NOrMAL, TEMPLATE FILTERING, and NucPosSimulator) on several synthetic datasets as well as real data for S. cerevisiae and P. falciparum. Experimental results show that our approach produces more accurate nucleosome maps with a higher number of non-overlapping nucleosomes than other tools. PMID:25252810

  3. 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.

  4. 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

  5. Accurate Calculation of Hydration Free Energies using Pair-Specific Lennard-Jones Parameters in the CHARMM Drude Polarizable Force Field

    PubMed Central

    Baker, Christopher M.; Lopes, Pedro E. M.; Zhu, Xiao; Roux, Benoît; MacKerell, Alexander D.

    2010-01-01

    Lennard-Jones (LJ) parameters for a variety of model compounds have previously been optimized within the CHARMM Drude polarizable force field to reproduce accurately pure liquid phase thermodynamic properties as well as additional target data. While the polarizable force field resulting from this optimization procedure has been shown to satisfactorily reproduce a wide range of experimental reference data across numerous series of small molecules, a slight but systematic overestimate of the hydration free energies has also been noted. Here, the reproduction of experimental hydration free energies is greatly improved by the introduction of pair-specific LJ parameters between solute heavy atoms and water oxygen atoms that override the standard LJ parameters obtained from combining rules. The changes are small and a systematic protocol is developed for the optimization of pair-specific LJ parameters and applied to the development of pair-specific LJ parameters for alkanes, alcohols and ethers. The resulting parameters not only yield hydration free energies in good agreement with experimental values, but also provide a framework upon which other pair-specific LJ parameters can be added as new compounds are parametrized within the CHARMM Drude polarizable force field. Detailed analysis of the contributions to the hydration free energies reveals that the dispersion interaction is the main source of the systematic errors in the hydration free energies. This information suggests that the systematic error may result from problems with the LJ combining rules and is combined with analysis of the pair-specific LJ parameters obtained in this work to identify a preliminary improved combining rule. PMID:20401166

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

    DOE PAGESBeta

    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.

  7. 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.

  8. MODEL-INDEPENDENT DETERMINATION OF CURVATURE PARAMETER USING H(z) AND D{sub A} (z) DATA PAIRS FROM BAO MEASUREMENTS

    SciTech Connect

    Li, Yun-Long; Li, Ti-Pei; Li, Shi-Yu; Zhang, Tong-Jie

    2014-07-01

    We present a model-independent determination of the curvature parameter Ω {sub k} using the Hubble parameter H(z) and the angular diameter distance D{sub A} (z) from recent baryon acoustic oscillation (BAO) measurements. Each H(z) and D{sub A} (z) pair from a BAO measurement can constrain a curvature parameter. The accuracy of the curvature measurement improves with increased redshift of H(z) and D{sub A} (z) data. By using the H(z) and D{sub A} (z) pair derived from a BAO Lyman α forest measurement at z = 2.36, the Ω {sub k} is confined to be –0.05 ± 0.06, which is consistent with the curvature of −0.037{sub −0.042}{sup +0.044} constrained by the nine year Wilkinson Microwave Anisotropy Probe data only. Considering future BAO measurements, at least one order of magnitude improvement of this curvature measurement can be expected.

  9. Coronal loops diagnostics using the parameters of U-burst harmonic pair at frequencies 10-70 MHz

    NASA Astrophysics Data System (ADS)

    Dorovskyy, V. V.; Melnik, V. N.; Konovalenko, A. A.; Bubnov, I. N.; Gridin, A. A.; Shevchuk, N. V.; Rucker, H. O.; Panchenko, M.

    2013-09-01

    The results of the first observations of solar sporadic radio emission using one section of the new being currently created Giant Ukrainian Radio Telescope (GURT) are presented. The parameters of inverted U-burst with harmonic structure observed with GURT are considered. The main attention is paid to the time delay between the fundamental and harmonic components. The analytical model explaining the observed time delay is proposed.

  10. 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.

  11. 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⊙.

  12. M3 Status and Science Discussion

    NASA Technical Reports Server (NTRS)

    Pieters, Carle

    2007-01-01

    Members of the M3 Science Team will attend the Chandrayaan-I Science Team Meeting in Bangalore, India to present a brief summary of instrument status and the near-term milestones (e.g., final I&T, pre-ship review). The principal purpose of the meeting is to interact with other members of the Chandrayaan-I Science Team to prepare for successful science return. The objectives are: 1) Characterize the diversity and extent of different types of basaltic volcanism; 2) Constrain evolution over time; and 3) Examine high priority regional sites.

  13. 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.

  14. 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.

  15. 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

  16. 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

  17. A carbon-13 nuclear magnetic resonance spectroscopic study of inter-proton pair order parameters: a new approach to study order and dynamics in phospholipid membrane systems.

    PubMed

    Urbina, J A; Moreno, B; Arnold, W; Taron, C H; Orlean, P; Oldfield, E

    1998-09-01

    We report a simple new nuclear magnetic resonance (NMR) spectroscopic method to investigate order and dynamics in phospholipids in which inter-proton pair order parameters are derived by using high resolution 13C cross-polarization/magic angle spinning (CP/MAS) NMR combined with 1H dipolar echo preparation. The resulting two-dimensional NMR spectra permit determination of the motionally averaged interpair second moment for protons attached to each resolved 13C site, from which the corresponding interpair order parameters can be deducted. A spin-lock mixing pulse before cross-polarization enables the detection of spin diffusion amongst the different regions of the lipid molecules. The method was applied to a variety of model membrane systems, including 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC)/sterol and 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC)/sterol model membranes. The results agree well with previous studies using specifically deuterium labeled or predeuterated phospholipid molecules. It was also found that efficient spin diffusion takes place within the phospholipid acyl chains, and between the glycerol backbone and choline headgroup of these molecules. The experiment was also applied to biosynthetically 13C-labeled ergosterol incorporated into phosphatidylcholine bilayers. These results indicate highly restricted motions of both the sterol nucleus and the aliphatic side chain, and efficient spin exchange between these structurally dissimilar regions of the sterol molecule. Finally, studies were carried out in the lamellar liquid crystalline (L alpha) and inverted hexagonal (HII) phases of 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE). These results indicated that phosphatidylethanolamine lamellar phases are more ordered than the equivalent phases of phosphatidylcholines. In the HII (inverted hexagonal) phase, despite the increased translational freedom, there is highly constrained packing of the lipid molecules, particularly in

  18. 26 CFR 1.401(m)-3 - Safe harbor requirements.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 5 2011-04-01 2011-04-01 false Safe harbor requirements. 1.401(m)-3 Section 1.401(m)-3 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Pension, Profit-Sharing, Stock Bonus Plans, Etc. § 1.401(m)-3...

  19. 26 CFR 1.401(m)-3 - Safe harbor requirements.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 5 2010-04-01 2010-04-01 false Safe harbor requirements. 1.401(m)-3 Section 1.401(m)-3 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES Pension, Profit-Sharing, Stock Bonus Plans, Etc. § 1.401(m)-3 Safe...

  20. Critical Schwinger Pair Production

    NASA Astrophysics Data System (ADS)

    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.

  1. 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

  2. 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…

  3. 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. PMID:650291

  4. Winning Pairs.

    ERIC Educational Resources Information Center

    Monsour, Florence

    2000-01-01

    Mentoring programs that pair experienced and first-time teachers are gaining prominence in supporting, developing, and retaining new teachers. The successful Beginning Teacher Assistance program at University of Wisconsin-River Falls was designed to give new K-12 teachers the opportunity for yearlong, structured support from mentor teachers. (MLH)

  5. Fabrication and metrology study for M3M of TMT

    NASA Astrophysics Data System (ADS)

    Luo, Xiao

    2014-09-01

    The M3M (Mirror 3 Mirror) of TMT (Thirty Meter Telescope) project is a3.5m×2.5m solid flat elliptical mirror. CIOMP is responsible for the fabrication of the M3M. A primary study on the fabrication and metrology is done in the past 2 years, and this paper introduces our work on the project. The fabrication strategy is based on large orbital tools and a plan combining with multiple measure methods is developed based on the requirement of M3M. A concept of dualsupporting system is also studied in the program to reduce the effect of gravity deformation.

  6. 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.

  7. 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.

  8. Modeling the radial distribution of blue stragglers in M3

    NASA Technical Reports Server (NTRS)

    Sigurdsson, Steinn; Davies, Melvyn B.; Bolte, Michael

    1994-01-01

    Recent surveys of the blue straggler (BS) population in the Galactic globular cluster M3 (NGC 5272) give the first complete characterization of the number density of BSs as a function of radius over an entire globular cluster. The BSs in M3 are overabundant at large radii and significantly underabundant at intermediate radii. Here we present the result of a simulation of the dynamical evolution of a population of BSs in a multimass model of M3. Assuming the BSs were formed in the core through binary interactions (Hut & Verbundt 1983; Leonard 1989; Sigurdsson & Phinney 1993; Hut et al. 1992b; Davies, Benz & Hills 1994), and given some very general assumptions about the recoil that occurs during stellar mergers in interacting binaries, we find an excellent fit to the observed radial distribution of BSs, suggesting strongly that most of the BSs in M3 were formed through binary collisions in the core.

  9. Study of tilt axis bearing arrangement for M3S of TMT project

    NASA Astrophysics Data System (ADS)

    Zhao, Hongchao; Zhang, Jingxu; Yang, Fei; An, Qichang; Su, Yanqin; Guo, Peng

    2014-09-01

    The tertiary mirror positioned assembly (M3PA) of the thirty meters telescope (TMT) is the largest tertiary mirror pointing system in the world. The tracking and pointing performance of M3PA is better than any other telescopes which have been built, and the working condition is even worse, so the designers face an enormous challenge. The tracking system includes the bottom rotator shaft and the tilt shaft. The study of this paper focuses on the tilt shaft. There are mainly three forms. The first form is one end fixed with the other unrestrained in axial direction. The second form uses two pairs of angular contact ball bearing. The last form lays two tape roller bearings. All of them can meet the requirements when the M3PA is vertical. But the first one becomes invalid when the M3PA is horizontal. We pay our attention on the study for the second arrangement method.. This bearing arrangement can produce a good stiffness, and increase the first modal frequency to 15.1Hz. In addition, some analysis were down to study the load applied on the balls. The results show that the maximum load is up to 5000N with the stress of 2300MPa.

  10. 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.

  11. 26 CFR 1.401(m)-3 - Safe harbor requirements.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... plan will not fail to satisfy the safe harbor matching contribution requirements of this section merely... rule. A plan that provides for safe harbor matching contributions will not fail to satisfy the... 26 Internal Revenue 5 2013-04-01 2013-04-01 false Safe harbor requirements. 1.401(m)-3 Section...

  12. 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...

  13. SYN1deg-M3Hour Ed3A

    Atmospheric Science Data Center

    2016-06-08

    ... and Order:  Reverb   Reverb Tutorial Subset/Visualization Tool: CERES Order Tool Order Data:  ... Detailed CERES SYN1deg Product Information Data Products Catalog:  DPC_SYN1deg-M3Hour_R5V1 ...

  14. 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.

  15. Measurement of charm mixing parameters and the neutral D meson decaying to a negative kaon-positive pion strong phase using quantum correlated neutral D meson-neutral anti-D meson pairs

    NASA Astrophysics Data System (ADS)

    Lincoln, Adam J.

    The decays of D0 and D0 mesons produced from e +e- annihilations at the psi'' resonance reflect quantum correlations so that decay rates are sensitive to interference between indistinguishable final states. Using the CLEO-c detector at the Cornell Electron Storage Ring, we measure the time-independent decay rates of D0 decays to K-pi +, K+pi-, several CP eigenstates, and semileptonic states. We make use of both partially and fully reconstructed D0 - D0 pairs. A chi2 minimization fitter extracts from these decay rates mixing and doubly Cabibbo suppressed decay parameters x2, y, r 2, and cos delta, along with isolated D 0 branching fractions for all input final states. By constraining the branching fractions and r2 with independent measurements, a first measurement of cos delta can be made.

  16. 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.

  17. Stromvil CCD Photometry in Globular Cluster M 3

    NASA Astrophysics Data System (ADS)

    Boyle, Richard P.; Janusz, R.; Philip, A. G. D.; Straizys, V.; Vrba, F.

    2007-12-01

    We observed the globular cluster M 3 in the 7-band Stromvil system plus Vilnius X-band at the 1.8-m Vatican Advanced Technology Telescope with a 2K CCD giving a 6-arcmin field. We observed the open cluster M 67 in the same run. Here from the residuals of many stars fit to quality CCD Vilnius photometry (Laugalys et al., 2004, Baltic Astronomy, 13, 1) we reshape and thus correct the initial flatfields. M 67 with a wide color base gives the color transformations of the run by calibrating from about 12 photoelectric standards in the Stromvil and similar Vilnius systems. In M 3 six photoelectric standards of moderate quality, all red stars of 13th magnitude in the Vilnius system calibrate the zero-point magnitude scale. Point-spread-function fitting to the stars in the crowded M 3 field resolves blends. With relatively short exposures of minutes a limiting magnitude V=15 is obtained with a signal/noise ratio about 100. So from this new photometry we subsequently can classify all types of stars and treat questions of reddening, distances, membership and metallicity at least at the horizontal branch of the cluster.

  18. 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

  19. Exploring the mineralogy of the Moon with M3

    NASA Astrophysics Data System (ADS)

    Pieters, C. M.

    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 sim 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 Carl e Pieters at Brown University and is being built by an experienced team at the Jet Propulsion Laboratory Data analysis and calibration are

  20. 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.

  1. 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

  2. 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.

  3. Directional dark matter detection with the DMTPC m3 experiment

    NASA Astrophysics Data System (ADS)

    Leyton, Michael; DMTPC Collaboration

    2016-05-01

    Directional reconstruction provides a unique way to positively identify signal interactions induced by dark matter particles, owing to the motion of the Earth through the galactic dark matter halo. Directional information can additionally serve as a powerful discriminant against neutron (and neutrino-induced) backgrounds that have the same final-state signature as a signal interaction. The Dark Matter Time Projection Chamber (DMTPC) collaboration uses gas-based TPC technology, with both optical and charge readout, to measure the directional anisotropy of nuclear recoils induced by particles traversing the detector volume. Here, we present preliminary results from recent calibration runs of the DMTPC m3 detector in a surface laboratory, as well as a study of its projected directional sensitivity.

  4. Longitudinal analysis of 25 sequential sample-pairs using a custom multiple myeloma mutation sequencing panel (M(3)P).

    PubMed

    Kortüm, K M; Langer, C; Monge, J; Bruins, L; Zhu, Y X; Shi, C X; Jedlowski, P; Egan, J B; Ojha, J; Bullinger, L; Kull, M; Ahmann, G; Rasche, L; Knop, S; Fonseca, R; Einsele, H; Stewart, A K; Braggio, Esteban

    2015-07-01

    Recent advances in genomic sequencing technologies now allow results from deep next-generation sequencing to be obtained within clinically meaningful timeframes, making this an attractive approach to better guide personalized treatment strategies. No multiple myeloma-specific gene panel has been established so far; we therefore designed a 47-gene-targeting gene panel, containing 39 genes known to be mutated in ≥3 % of multiple myeloma cases and eight genes in pathways therapeutically targeted in multiple myeloma (MM). We performed targeted sequencing on tumor/germline DNA of 25 MM patients in which we also had a sequential sample post treatment. Mutation analysis revealed KRAS as the most commonly mutated gene (36 % in each time point), followed by NRAS (20 and 16 %), TP53 (16 and 16 %), DIS3 (16 and 16 %), FAM46C (12 and 16 %), and SP140 (12 and 12 %). We successfully tracked clonal evolution and identified mutation acquisition and/or loss in FAM46C, FAT1, KRAS, NRAS, SPEN, PRDM1, NEB, and TP53 as well as two mutations in XBP1, a gene associated with bortezomib resistance. Thus, we present the first longitudinal analysis of a MM-specific targeted sequencing gene panel that can be used for individual tumor characterization and for tracking clonal evolution over time. PMID:25743686

  5. 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.

  6. ESA M3 mission candidate EChO

    NASA Astrophysics Data System (ADS)

    Puig, L.; Isaak, K. G.; Escudero, I.; Martin, D.; Crouzet, P.-E.; Rando, N.

    2011-09-01

    The Exoplanet Characterisation Observatory (EChO) is a medium class mission candidate within the science program Cosmic Vision 2015-2025 of the European Space Agency. It was selected in February 2011 as one of 4 M3 mission candidates to enter an assessment phase. The assessment activities start with the definition of science and mission requirements as well as of a preliminary model payload, followed by an internal Concurrent Design Facility (CDF) study. Parallel industrial studies will follow in 2012, after which the 4 missions will be reviewed to identify candidates entering definition phase studies in 2013. EChO aims at characterising the atmosphere of known transiting exoplanets, potentially from giant Hot Jupiters down to Super-Earths orbiting in the habitable zone of M-dwarf stars. It will use a 1 m class telescope, feeding a spectrometer covering the wave lengths from 0.4 to 11 microns with a potential extension to 16 microns. While spatial differentiation of the exoplanet and its host star is not necessary, spectral differentiation will be achieved by making differential measurements of in- and out- of transit frames to cancel the star signal. This paper describes critical requirements, and gives an overview of the model payload design. It also reports on the results of the CDF.

  7. Targeting Ilmenite on the Moon Using M3 Hyperspectal Imagery

    NASA Astrophysics Data System (ADS)

    Standart, D. L.; Hurtado, J. M.

    2013-12-01

    In-situ resource utilization (ISRU) will be a key technology in sustained human exploration of the solar system. The lunar surface hosts a variety of potentially exploitable resources. For example, KREEP (potassium, rare earth elements, phosphorus) material on the Moon is shown to be relatively rich in ilmenite (FeTiO3 ) and other useful materials. By targeting areas with anomalously high Th signatures, as seen by Lunar Prospector gamma ray spectroscopy (LP-GRS), we have mapped areas with the highest concentrations of ilmenite-rich material on the nearside of the Moon. To map Th, we employ a continuum slope band depth (CSBD) technique that takes advantage of the fact that the visible-infrared reflectance spectrum of ilmenite exhibits low reflectance and a flat continuum slope. As a result, the spectra of materials bearing ilmenite will also have a lower reflectance and a flattened continuum slope. These effects may also obscure spectral absorption features indicative of other minerals, such as pyroxene, within the host rock. We use the results of the CSBD analysis to construct ilmenite classification maps that can be compared to Lunar Reconnaissance Orbiter (LRO) Wide Angle Camera (WAC) ultraviolet/visible-infrared composite imagery. The LRO-WAC and M3 images together provide strong evidence for the presence of high concentrations of ilmenite, which can then be related to the distribution of associated KREEP material. The sites of interest for analyzing ilmenite and Th in this study include Gruithuisen Domes (including the Federov feature), Hansteen Alpha, Lassell Crater, and the Compton Belkovich Thorium Anomaly (CBTA). Each of these sites is also geologically interesting because they contain what are interpreted to be non-mare silicic volcanic features.

  8. 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

  9. Orbiting pairs of walking droplets

    NASA Astrophysics Data System (ADS)

    Siefert, Emmanuel; Bush, John W. M.; Oza, Anand

    2015-11-01

    Droplets may self-propel on the surface of a vibrating fluid bath, pushed forward by their own Faraday pilot-wave field. We present the results of a combined experimental and theoretical investigation of the interaction of pairs of such droplets. Particular attention is given to characterizing the system's dependence on the vibrational forcing of the bath and the impact parameter of the walking droplets. Observed criteria for the capture and stability of orbital pairs are rationalized by accompanying theoretical developments. Thanks to the NSF.

  10. 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

  11. Geochemical and mineralogical analysis of Gruithuisen region on Moon using M3 and DIVINER images

    NASA Astrophysics Data System (ADS)

    Kusuma, K. N.; Sebastian, N.; Murty, S. V. S.

    2012-07-01

    Spectral information from the Moon Mineralogy Mapper (M3) onboard Chandrayaan-1 and DIVINER Lunar Radiometer onboard LRO have been used for geochemical and mineralogical characterisation of the Gruithuisen region on Moon along with morphometrical information from LOLA Digital elevation model. The apparent reflectance of M3 on global mode is used for (1) spectral characterisation (2) estimating the abundance of Ti and Fe using Lucey's method and (3) discriminating non-mare region from mare regions by means of Minimum Noise Fraction (MNF) transform and Integrated Band Depth (IBD) parameters. Christensen frequency (CF) value derived from DIVINER data is used to delineate the silica saturated lithology from the undersaturated rocks as well as to delineate their spatial spread. Low values of FeO, TiO2, and IBD indicate non-mare nature of the domes and highland material, also supplemented by CF values. The highland rocks represent signatures of sodic plagioclase, the end result of plagioclase crystallisation from Lunar Magma Ocean. Compositional variations are observed among the domes. NW dome has highest silica concentration than the other two domes and in turn higher viscosity. It is most likely that the three domes tapped residual liquid from different locations of the residual magma chamber which is in constant mixing. The extrusion is probably a localised phenomenon, where urKREEP welled out along the zone of crustal weakness formed by Imbrium Impact. It is likely that δ dome has extruded over a larger time span than other two features.

  12. RPI-AM and RPI-AF, a pair of mesh-based, size-adjustable adult male and female computational phantoms using ICRP-89 parameters and their calculations for organ doses from monoenergetic photon beams

    NASA Astrophysics Data System (ADS)

    Zhang, Juying; Hum Na, Yong; Caracappa, Peter F.; Xu, X. George

    2009-10-01

    This paper describes the development of a pair of adult male and adult female computational phantoms that are compatible with anatomical parameters for the 50th percentile population as specified by the International Commission on Radiological Protection (ICRP). The phantoms were designed entirely using polygonal mesh surfaces—a Boundary REPresentation (BREP) geometry that affords the ability to efficiently deform the shape and size of individual organs, as well as the body posture. A set of surface mesh models, from Anatomium™ 3D P1 V2.0, including 140 organs (out of 500 available) was adopted to supply the basic anatomical representation at the organ level. The organ masses were carefully adjusted to agree within 0.5% relative error with the reference values provided in the ICRP Publication 89. The finalized phantoms have been designated the RPI adult male (RPI-AM) and adult female (RPI-AF) phantoms. For the purposes of organ dose calculations using the MCNPX Monte Carlo code, these phantoms were subsequently converted to voxel formats. Monoenergetic photons between 10 keV and 10 MeV in six standard external photon source geometries were considered in this study: four parallel beams (anterior-posterior, posterior-anterior, left lateral and right lateral), one rotational and one isotropic. The results are tabulated as fluence-to-organ-absorbed-dose conversion coefficients and fluence-to-effective-dose conversion coefficients and compared against those derived from the ICRP computational phantoms, REX and REGINA. A general agreement was found for the effective dose from these two sets of phantoms for photon energies greater than about 300 keV. However, for low-energy photons and certain individual organs, the absorbed doses exhibit profound differences due to specific anatomical features. For example, the position of the arms affects the dose to the lung by more than 20% below 300 keV in the lateral source directions, and the vertical position of the testes

  13. RPI-AM and RPI-AF, a pair of mesh-based, size-adjustable adult male and female computational phantoms using ICRP-89 parameters and their calculations for organ doses from monoenergetic photon beams

    PubMed Central

    Zhang, Juying; Na, Yong Hum; Caracappa, Peter F; Xu, X George

    2010-01-01

    This paper describes the development of a pair of adult male and adult female computational phantoms that are compatible with anatomical parameters for the 50th percentile population as specified by the International Commission on Radiological Protection (ICRP). The phantoms were designed entirely using polygonal mesh surfaces—a Boundary REPresentation (BREP) geometry that affords the ability to efficiently deform the shape and size of individual organs, as well as the body posture. A set of surface mesh models, from Anatomium™ 3D P1 V2.0, including 140 organs (out of 500 available) was adopted to supply the basic anatomical representation at the organ level. The organ masses were carefully adjusted to agree within 0.5% relative error with the reference values provided in the ICRP Publication 89. The finalized phantoms have been designated the RPI adult male (RPI-AM) and adult female (RPI-AF) phantoms. For the purposes of organ dose calculations using the MCNPX Monte Carlo code, these phantoms were subsequently converted to voxel formats. Monoenergetic photons between 10 keV and 10 MeV in six standard external photon source geometries were considered in this study: four parallel beams (anterior–posterior, posterior–anterior, left lateral and right lateral), one rotational and one isotropic. The results are tabulated as fluence-to-organ-absorbed-dose conversion coefficients and fluence-to-effective-dose conversion coefficients and compared against those derived from the ICRP computational phantoms, REX and REGINA. A general agreement was found for the effective dose from these two sets of phantoms for photon energies greater than about 300 keV. However, for low-energy photons and certain individual organs, the absorbed doses exhibit profound differences due to specific anatomical features. For example, the position of the arms affects the dose to the lung by more than 20% below 300 keV in the lateral source directions, and the vertical position of the testes

  14. 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.

  15. 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.

  16. 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.

  17. Cooper Pairs in Insulators?!

    ScienceCinema

    James Valles

    2010-01-08

    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. 

  18. 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.

  19. 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

  20. Electron pairing without superconductivity

    NASA Astrophysics Data System (ADS)

    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

    2015-05-01

    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.

  1. 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.

  2. The Swift UVOT Stars Survey. II. RR Lyrae Stars in M3 and M15

    NASA Astrophysics Data System (ADS)

    Siegel, Michael H.; Porterfield, Blair L.; Balzer, Benjamin G.; Hagen, Lea M. Z.

    2015-10-01

    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.

  3. Transient Simulation of the DLR M3.1 Testbench: Methods and First Results

    NASA Astrophysics Data System (ADS)

    Manfletti, C.; Sender, J.

    2009-01-01

    Analysis of transient phases in liquid rocket engines play a major role in the design of the engines, as well as in the configuration and tailoring of the transient phases themselves. Testing of existing as well as future rocket engines, must therefore consider transient aspects, such as pre-cooling, priming, as well as ignition both experimentally as well as numerically. The flow behaviour within the various engine components is strongly dictated by the existing pressure and temperature fields. Ideally the flow through the engine feed lines is a one phase-flow. This is however not necessarily the case and a two-phase flow may lead to drastic changes in the behaviour. The application of the program TLRE to the simulation of the DLR test bench M3.1 is presented. The focus lies on the two-phase flow associated phenomena and the numerical resolution of these phenomena with the implementation of the lumped parameter method (LPM). A brief introduction of the relevant LPM characteristics is given. This is followed by a description of the relevant and observed two-phase flow phenomena and regimes and the numerical solution method. In conclusion both the main results of the work performed so far, which highlights the importance of the measurement system and how this needs to be taken into account during analysis processes, and a future roadmap for subsequent program evolution and applications are outlined.

  4. 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.

  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. 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

  7. 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.

  8. Decrease in the Sensitivity of Myocardium to M3 Muscarinic Receptor Stimulation during Postnatal Ontogenisis.

    PubMed

    Tapilina, S V; Abramochkin, D V

    2016-01-01

    Type 3 muscarinic receptors (M3 receptors) participate in the mediation of cholinergic effects in mammalian myocardium, along with M2 receptors. However, myocardium of adult mammals demonstrates only modest electrophysiological effects in response to selective stimulation of M3 receptors which are hardly comparable to the effects produced by M2 stimulation. In the present study, the effects of selective M3 stimulation induced by application of the muscarinic agonist pilocarpine (10 μM) in the presence of the selective M2 blocker methoctramine (100 nM) on the action potential (AP) waveform were investigated in isolated atrial and ventricular preparations from newborn and 3-week-old rats and compared to those in preparations from adult rats. In the atrial myocardium, stimulation of M3 receptors produced a comparable reduction of AP duration in newborn and adult rats, while in 3-week-old rats the effect was negligible. In ventricular myocardial preparations from newborn rats, the effect of M3 stimulation was more than 3 times stronger compared to that from adult rats, while preparations from 3-week old rats demonstrated no definite effect, similarly to atrial preparations. In all studied types of cardiac preparations, the effects of M3 stimulation were eliminated by the selective M3 antagonist 4-DAMP (10 nM). The results of RT-PCR show that the amount of product of the M3 receptor gene decreases with the maturation of animals both in atrial and ventricular myocardium. We concluded that the contribution of M3 receptors to the mediation of cardiac cholinergic responses decreases during postnatal ontogenesis. These age-related changes may be associated with downregulation of M3 receptor gene expression. PMID:27437147

  9. Decrease in the Sensitivity of Myocardium to M3 Muscarinic Receptor Stimulation during Postnatal Ontogenisis

    PubMed Central

    Tapilina, S.V.; Abramochkin, D.V.

    2016-01-01

    Type 3 muscarinic receptors (M3 receptors) participate in the mediation of cholinergic effects in mammalian myocardium, along with M2 receptors. However, myocardium of adult mammals demonstrates only modest electrophysiological effects in response to selective stimulation of M3 receptors which are hardly comparable to the effects produced by M2 stimulation. In the present study, the effects of selective M3 stimulation induced by application of the muscarinic agonist pilocarpine (10 μM) in the presence of the selective M2 blocker methoctramine (100 nM) on the action potential (AP) waveform were investigated in isolated atrial and ventricular preparations from newborn and 3-week-old rats and compared to those in preparations from adult rats. In the atrial myocardium, stimulation of M3 receptors produced a comparable reduction of AP duration in newborn and adult rats, while in 3-week-old rats the effect was negligible. In ventricular myocardial preparations from newborn rats, the effect of M3 stimulation was more than 3 times stronger compared to that from adult rats, while preparations from 3-week old rats demonstrated no definite effect, similarly to atrial preparations. In all studied types of cardiac preparations, the effects of M3 stimulation were eliminated by the selective M3 antagonist 4-DAMP (10 nM). The results of RT-PCR show that the amount of product of the M3 receptor gene decreases with the maturation of animals both in atrial and ventricular myocardium. We concluded that the contribution of M3 receptors to the mediation of cardiac cholinergic responses decreases during postnatal ontogenesis. These age-related changes may be associated with downregulation of M3 receptor gene expression. PMID:27437147

  10. 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.

  11. Multiscale structures in relativistic pair plasmas

    SciTech Connect

    Iqbal, M.; Berezhiani, V. I.; Yoshida, Z.

    2008-03-15

    The steady-state solution of a pair plasma with relativistic thermal velocity of the constituent particles (electrons and positrons) is investigated. The relaxed state can be written as a superposition of three Beltrami fields. Generally, the associated scale parameters could be a complex conjugate pair and a real one. It is shown that at higher thermal energies, all the scale parameters become real. It is also observed that one component gets a large scale (system size) while the other two components appear with small scale of the order of the skin depth at relativistic temperature.

  12. Inhibition of Intimal Hyperplasia in Transgenic Mice Conditionally Expressing the Chemokine-Binding Protein M3

    PubMed Central

    Pyo, Robert; Jensen, Kristian K.; Wiekowski, Maria T.; Manfra, Denise; Alcami, Antonio; Taubman, Mark B.; Lira, Sergio A.

    2004-01-01

    Chemokines have been implicated in the pathogenesis of a wide variety of diseases. This report describes the generation of transgenic mice that conditionally express M3, a herpesvirus protein that binds and inhibits chemokines. In response to doxycycline, M3 expression was induced in a variety of tissues and M3 was detectable in the blood by Western blotting. No gross or histological abnormalities were seen in mice expressing M3. To determine whether M3 expression could modify a significant pathophysiological response, we examined its effect on the development of intimal hyperplasia in response to femoral arterial injury. Intimal hyperplasia is thought to play a critical role in the development of restenosis after percutaneous transluminal coronary angioplasty and in the progression of atherosclerosis. Induction of M3 expression resulted in a 67% reduction in intimal area and a 68% reduction in intimal/medial ratio after femoral artery injury. These data support a role for chemokines in regulating intimal hyperplasia and suggest that M3 may be effective in attenuating this process. This transgenic mouse model should be a valuable tool for investigating the role of chemokines in a variety of pathological states. PMID:15161661

  13. Inhibition of intimal hyperplasia in transgenic mice conditionally expressing the chemokine-binding protein M3.

    PubMed

    Pyo, Robert; Jensen, Kristian K; Wiekowski, Maria T; Manfra, Denise; Alcami, Antonio; Taubman, Mark B; Lira, Sergio A

    2004-06-01

    Chemokines have been implicated in the pathogenesis of a wide variety of diseases. This report describes the generation of transgenic mice that conditionally express M3, a herpesvirus protein that binds and inhibits chemokines. In response to doxycycline, M3 expression was induced in a variety of tissues and M3 was detectable in the blood by Western blotting. No gross or histological abnormalities were seen in mice expressing M3. To determine whether M3 expression could modify a significant pathophysiological response, we examined its effect on the development of intimal hyperplasia in response to femoral arterial injury. Intimal hyperplasia is thought to play a critical role in the development of restenosis after percutaneous transluminal coronary angioplasty and in the progression of atherosclerosis. Induction of M3 expression resulted in a 67% reduction in intimal area and a 68% reduction in intimal/medial ratio after femoral artery injury. These data support a role for chemokines in regulating intimal hyperplasia and suggest that M3 may be effective in attenuating this process. This transgenic mouse model should be a valuable tool for investigating the role of chemokines in a variety of pathological states. PMID:15161661

  14. Electron Pairing Without Superconductivity

    NASA Astrophysics Data System (ADS)

    Levy, Jeremy; Cheng, G.; Tomczyk, M.; Lu, S.; Veazey, J. P.; Huang, M.; Irvin, P.; Ryu, S.; Lee, H.; Eom, C.-B.; Hellberg, C. S.

    2015-03-01

    Strontium titanate (SrTiO3) exhibits an extremely low carrier density threshold for superconductivity, and possesses a phase diagram similar to high-temperature superconductors--two factors that suggest an unconventional pairing mechanism. We describe transport experiments with nanowire-based quantum dots localized at the interface between SrTiO3 and LaAlO3. Electrostatic gating of the quantum dot reveals a series of two-electron conductance resonances--paired electron states--that bifurcate above a critical magnetic field Bp 1-4 Tesla, an order of magnitude larger than the superconducting critical magnetic field. For B Bp, the resonances exhibit a linear Zeeman-like energy splitting. Electron pairing is stable at temperatures as high as T = 900 mK, far above the superconducting transition temperature (Tc 300 mK). 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 an attractive-U Hubbard model that describes real-space electron pairing as a precursor to superconductivity. This work was supported by ARO MURI W911NF-08-1-0317 (J.L.), AFOSR MURI FA9550-10-1-0524 (C.-B.E., J.L.) and FA9550-12-1-0342 (C.-B.E.), and grants from the National Science Foundation DMR-1104191 (J.L.), DMR.

  15. 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. PMID:8800222

  16. String pair production in non homogeneous backgrounds

    NASA Astrophysics Data System (ADS)

    Bolognesi, S.; Rabinovici, E.; Tallarita, G.

    2016-04-01

    We consider string pair production in non homogeneous electric backgrounds. We study several particular configurations which can be addressed with the Euclidean world-sheet instanton technique, the analogue of the world-line instanton for particles. In the first case the string is suspended between two D-branes in flat space-time, in the second case the string lives in AdS and terminates on one D-brane (this realizes the holographic Schwinger effect). In some regions of parameter space the result is well approximated by the known analytical formulas, either the particle pair production in non-homogeneous background or the string pair production in homogeneous background. In other cases we see effects which are intrinsically stringy and related to the non-homogeneity of the background. The pair production is enhanced already for particles in time dependent electric field backgrounds. The string nature enhances this even further. For spacial varying electrical background fields the string pair production is less suppressed than the rate of particle pair production. We discuss in some detail how the critical field is affected by the non-homogeneity, for both time and space dependent electric field backgrouds. We also comment on what could be an interesting new prediction for the small field limit. The third case we consider is pair production in holographic confining backgrounds with homogeneous and non-homogeneous fields.

  17. Supernovae in paired galaxies

    NASA Astrophysics Data System (ADS)

    Nazaryan, T. A.; Petrosian, A. R.; Hakobyan, A. A.; Adibekyan, V. Zh.; Kunth, D.; Mamon, G. A.; Turatto, M.; Aramyan, L. S.

    2014-07-01

    We investigate the influence of close neighbor galaxies on the properties of supernovae (SNe) and their host galaxies using 56 SNe located in pairs of galaxies with different levels of star formation (SF) and nuclear activity. The mean distance of type II SNe from nuclei of hosts is greater by about a factor of 2 than that of type Ibc SNe. The distributions and mean distances of SNe are consistent with previous results compiled with the larger sample. For the first time it is shown that SNe Ibc are located in pairs with significantly smaller difference of radial velocities between components than pairs containing SNe Ia and II. We consider this as a result of higher star formation rate (SFR) of these closer systems of galaxies.

  18. Applications of balanced pairs

    NASA Astrophysics Data System (ADS)

    Li, HuanHuan; Wang, JunFu; Huang, ZhaoYong

    2016-05-01

    Let $(\\mathscr{X}$, $\\mathscr{Y})$ be a balanced pair in an abelian category. We first introduce the notion of cotorsion pairs relative to $(\\mathscr{X}$, $\\mathscr{Y})$, and then give some equivalent characterizations when a relative cotorsion pair is hereditary or perfect. We prove that if the $\\mathscr{X}$-resolution dimension of $\\mathscr{Y}$ (resp. $\\mathscr{Y}$-coresolution dimension of $\\mathscr{X}$) is finite, then the bounded homotopy category of $\\mathscr{Y}$ (resp. $\\mathscr{X}$) is contained in that of $\\mathscr{X}$ (resp. $\\mathscr{Y}$). As a consequence, we get that the right $\\mathscr{X}$-singularity category coincides with the left $\\mathscr{Y}$-singularity category if the $\\mathscr{X}$-resolution dimension of $\\mathscr{Y}$ and the $\\mathscr{Y}$-coresolution dimension of $\\mathscr{X}$ are finite.

  19. 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.

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

    NASA Astrophysics Data System (ADS)

    Breslau, J. A.; Bhattacharjee, A.

    2015-06-01

    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.

  1. 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

  2. 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

  3. 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

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

    PubMed Central

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

    2014-01-01

    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. PMID:25501592

  5. 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.

  6. 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.

  7. 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

  8. 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.

  9. Large Impact Melt Flow Feature identified across the floor of Copernicus Crater by Moon Mineralogy Mapper (M3)

    NASA Astrophysics Data System (ADS)

    Dhingra, D.; Pieters, C. M.; Head, J. W.

    2011-12-01

    Impact melt is normally one of the primary products of a large cratering event. The production of melt, its geographic distribution and the timing of its formation in the sequence of events during the cratering process depends on several parameters including size and velocity of the impactor, angle of impact, nature of pre-existing topography and target lithology. All of these parameters influence the size of the resulting crater as well as the character and fate of the melt produced during the event. We report here a very large impact melt flow feature across the floor of Copernicus crater identified with near-infrared spectra from M3. Copernicus is a relatively young impact crater ~100 km in diameter, located on the equatorial nearside of the Moon. The NW quadrant of the crater appears to contain a thick pool of impact melt. The new flow feature, with a length of ~30 km and flow lobes ~4-6 km wide, lies across the eastern portion of this melt deposit. Principal component analysis of M3 spectral data reveals this feature prominently in the 5th principal component. Spectroscopically, the flow feature differs from its surroundings mostly at longer M3 NIR wavelengths. Further analysis of the M3 data will focus on the compositional aspects and physical properties of this flow feature and its relation to nearby regions. An interesting aspect of the flow feature is its restricted occurrence between the northern wall and central peaks of the Copernicus crater. Several hypotheses, concerning this geologic setting, sourcing of the melt in the flow feature and its flow direction, are being explored. Two hypotheses in context of the melt sourcing include: 1) accumulation of the scattered melted material and drainage along a preferred slope or 2) fallback of large volume of melt that was lofted in a preferred direction during the impact event. The occurrence of such a large sized flow feature also suggests that the impact melt was very mobile and therefore probably poor in

  10. 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.

    2016-04-01

    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.

  11. 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.

  12. 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.

  13. Protected Flux Pairing Qubit

    NASA Astrophysics Data System (ADS)

    Bell, Matthew; Zhang, Wenyuan; Ioffe, Lev; Gershenson, Michael

    2014-03-01

    We have studied the coherent flux tunneling in a qubit containing two submicron Josephson junctions shunted by a superinductor (a dissipationless inductor with an impedance much greater than the resistance quantum). The two low energy quantum states of this device, 0 and 1, are represented by even and odd number of fluxes in the loop, respectively. This device is dual to the charge pairing Josephson rhombi qubit. The spectrum of the device, studied by microwave spectroscopy, reflects the interference between coherent quantum phase slips in the two junctions (the Aharonov-Casher effect). The time domain measurements demonstrate the suppression of the qubit's energy relaxation in the protected regime, which illustrates the potential of this flux pairing device as a protected quantum circuit. Templeton Foundation, NSF, and ARO.

  14. 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

  15. Wall touching kink mode calculations with the M3D code

    NASA Astrophysics Data System (ADS)

    Breslau, J. A.

    2014-10-01

    In recent years there have been a number of results published concerning the transient vessel currents and forces occurring during a tokamak VDE, as predicted by simulations with the nonlinear MHD code M3D. The nature of the simulations is such that these currents and forces occur at the boundary of the computational domain, making the proper choice of boundary conditions critical to the reliability of the results. The M3D boundary condition includes the prescription that the normal component of the velocity vanish at the wall. It has been argued that this prescription invalidates the calculations because it would seem to rule out the possibility of advection of plasma surface currents into the wall. This claim has been tested by applying M3D to an idealized case - a kink-unstable plasma column - in order to abstract the essential physics from the complications involved in the attempt to model real devices. While comparison of the results is complicated by effects arising from the higher dimensionality and complexity of M3D, we have verified 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.

  16. Impaired muscarinic type 3 (M3) receptor/PKC and PKA pathways in islets from MSG-obese rats.

    PubMed

    Ribeiro, Rosane Aparecida; Balbo, Sandra Lucinei; Roma, Letícia Prates; Camargo, Rafael Ludemann; Barella, Luiz Felipe; Vanzela, Emerielle Cristine; de Freitas Mathias, Paulo Cesar; Carneiro, Everardo Magalhães; Boschero, Antonio Carlos; Bonfleur, Maria Lúcia

    2013-07-01

    Monosodium glutamate-obese rats are glucose intolerant and insulin resistant. Their pancreatic islets secrete more insulin at increasing glucose concentrations, despite the possible imbalance in the autonomic nervous system of these rats. Here, we investigate the involvement of the cholinergic/protein kinase (PK)-C and PKA pathways in MSG β-cell function. Male newborn Wistar rats received a subcutaneous injection of MSG (4 g/kg body weight (BW)) or hyperosmotic saline solution during the first 5 days of life. At 90 days of life, plasma parameters, islet static insulin secretion and protein expression were analyzed. Monosodium glutamate rats presented lower body weight and decreased nasoanal length, but had higher body fat depots, glucose intolerance, hyperinsulinemia and hypertrigliceridemia. Their pancreatic islets secreted more insulin in the presence of increasing glucose concentrations with no modifications in the islet-protein content of the glucose-sensing proteins: the glucose transporter (GLUT)-2 and glycokinase. However, MSG islets presented a lower secretory capacity at 40 mM K(+) (P < 0.05). The MSG group also released less insulin in response to 100 μM carbachol, 10 μM forskolin and 1 mM 3-isobutyl-1-methyl-xantine (P < 0.05, P < 0.0001 and P < 0.01). These effects may be associated with a the decrease of 46 % in the acetylcholine muscarinic type 3 (M3) receptor, and a reduction of 64 % in PKCα and 36 % in PKAα protein expressions in MSG islets. Our data suggest that MSG islets, whilst showing a compensatory increase in glucose-induced insulin release, demonstrate decreased islet M3/PKC and adenylate cyclase/PKA activation, possibly predisposing these prediabetic rodents to the early development of β-cell dysfunction. PMID:23652999

  17. 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.

  18. Structural Basis of M3 Muscarinic Receptor Dimer/Oligomer Formation*

    PubMed Central

    McMillin, Sara M.; Heusel, Moritz; Liu, Tong; Costanzi, Stefano; Wess, Jürgen

    2011-01-01

    Class A G protein-coupled receptors (GPCRs) are known to form dimers and/or oligomeric arrays in vitro and in vivo. These complexes are thought to play important roles in modulating class A GPCR function. Many studies suggest that residues located on the “outer” (lipid-facing) surface of the transmembrane (TM) receptor core are critically involved in the formation of class A receptor dimers (oligomers). However, no clear consensus has emerged regarding the identity of the TM helices or TM subsegments involved in this process. To shed light on this issue, we have used the M3 muscarinic acetylcholine receptor (M3R), a prototypic class A GPCR, as a model system. Using a comprehensive and unbiased approach, we subjected all outward-facing residues (70 amino acids total) of the TM helical bundle (TM1–7) of the M3R to systematic alanine substitution mutagenesis. We then characterized the resulting mutant receptors in radioligand binding and functional studies and determined their ability to form dimers (oligomers) in bioluminescence resonance energy transfer saturation assays. We found that M3R/M3R interactions are not dependent on the presence of one specific structural motif but involve the outer surfaces of multiple TM subsegments (TM1–5 and -7) located within the central and endofacial portions of the TM receptor core. Moreover, we demonstrated that the outward-facing surfaces of most TM helices play critical roles in proper receptor folding and/or function. Guided by the bioluminescence resonance energy transfer data, molecular modeling studies suggested the existence of multiple dimeric/oligomeric M3R arrangements, which may exist in a dynamic equilibrium. Given the high structural homology found among all class A GPCRs, our results should be of considerable general relevance. PMID:21685385

  19. 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.

  20. 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.

  1. Corrosion cracking of 03N18K1M3TYu and 02N12Kh5M3 maraging steels in chloride solutions

    SciTech Connect

    Pavlov, V.N.; Chumalo, G.V.; Vereshchagin, A.N.; Melekhov, R.K.

    1987-07-01

    The authors investigate the electrochemical behavior in 0.5% NaCl solution and 42% MgCl/sub 2/ solution and the tendency toward corrosion cracking was determined in boiling 0.5% chloride solution of the cobalt-containing maraging steels in the title. Weld specimens and specimens of the base metal of 03N18K1M3TYu steel were tested in 3% NaCl solution for resistance to corrosion cracking. Additional investigations were made of specimens of that steel with previously created fatigue cracks of the base metal and the weld specimens in 3% NaCl solutions, since that steel is a promising material for structures operating in sea water and low concentration chloride solutions.

  2. Complete Genome Sequence of the Novel Leech Symbiont Mucinivorans hirudinis M3T

    PubMed Central

    Bomar, Lindsey

    2015-01-01

    Mucinivorans hirudinis M3T was isolated from the digestive tract of the medicinal leech, Hirudo verbana, and is the type species of a new genus within the Rikenellaceae. Here, we report the complete annotated genome sequence of this bacterium. PMID:25657285

  3. 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.

  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. Determination of the pairing-strength constants in the isovector plus isoscalar pairing case

    NASA Astrophysics Data System (ADS)

    Mokhtari, D.; Fellah, M.; Allal, N. H.

    2016-05-01

    A method for the determination of the pairing-strength constants, in the neutron-proton (n-p) isovector plus isoscalar pairing case, is proposed in the framework of the BCS theory. It is based on the fitting of these constants to reproduce the experimentally known pairing gap parameters as well as the root-mean-squared (r.m.s) charge radii values. The method is applied to some proton-rich even-even nuclei. The single-particle energies used are those of a deformed Woods-Saxon mean field. It is shown that the obtained value of the ratio GnpT=0/G npT=1 is of the same order as the ones, arbitrary chosen, of some previous works. The effect of the inclusion of the isoscalar n-p pairing in the r.m.s matter radii is then numerically studied for the same nuclei.

  6. Kinetics of vortex formation in superconductors with d pairing

    NASA Astrophysics Data System (ADS)

    Filippov, A. E.; Radievsky, A. V.; Zeltser, A. S.

    1996-08-01

    We study the kinetics of vortex formation in superconductors with d pairing. We find order-parameter peculiarities and associated magnetic field maxima at intermediate stages of the evolution from the disordered to the ordered state.

  7. 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

  8. Experiments on a Cooper pair insulator

    NASA Astrophysics Data System (ADS)

    Nguyen, Hung Q.

    At temperatures below 1K, nm thick a-Bi/Sb films, patterned with a nanohoneycomb array of holes, exhibit a novel electronic state consisting of localized Cooper pairs[1]. The Superconductor Insulator Transition (SIT), a phenomenon where the ground state of electrons is tuned from a superconducting to an insulating state, on this patterned homogeneous system shows a clear bosonic nature with activated transport on the insulating side. To date, this homogeneous system is the only one that shows clear evidence for the localization of Cooper pairs. Experiments are described that were performed to further characterize the properties of the localized Cooper pair state and its superconductor to insulator transitions. We show that: (i) The shape of the magnetoresistance (MR) oscillations, which indicate the presence of Cooper pairs in these multiply connected systems, depends on the geometry of the underlying substrates, but not on parameters like the temperature or thickness of the films. The magnetic field tuned SITs of films that are just thick enough to superconduct at zero magnetic field exhibit a common critical sheet resistance separating the superconducting and insulating phases in the range of 3.5 to 5kO. We also report a new type of SIT, an incommensurability driven SIT, which occurs due to the interplay of magnetic field and disorder in the arrangement of the honeycomb array of holes. (ii) The Cooper pair insulator state exhibits a giant positive MR, which peaks at a field estimated to be sufficient to break the pairs. The electrical transport on the low field side of the peak is activated. At the highest fields, it resembles G ˜ log(T), which is consistent with the behavior expected for weakly localized electrons rather than strongly localized Cooper pairs. We discuss this MR peak, compare it to that observed in other amorphous systems and propose a zero temperature phase diagram for these films.

  9. 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. PMID:24727280

  10. 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.

  11. 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.

  12. Multiprocessor switch with selective pairing

    SciTech Connect

    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

  13. 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.

  14. 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.

  15. Pair Cascades and Deathlines in Offset Magnetic Dipole Fields

    NASA Technical Reports Server (NTRS)

    Harding, Alice; Muslimov, Alex

    2010-01-01

    We investigate electron-positron pair cascades in a dipole magnetic field whose axis is offset from the neutron star center. In such a field geometry, the polar cap is displaced from the neutron star symmetry axis and the field line radius of curvature is modified. Using the modified parallel electric field near the polar cap of an offset dipole, we simulate pair cascades to determine the pair deathlines and pair multiplicities as a function of the offset parameter. We find that the pair multiplicity can change dramatically with a modest offset, with a significant increase on one side of the polar cap. Lower pair deathlines allow a larger fraction of the pulsar population, that include old and millisecond pulsars, to produce cascades with high multiplicity.

  16. The Development of M3S-Based GPS Navchair and Tele-Monitor System.

    PubMed

    Wu, Yi-Hui; Lu, Bing-Yuh; Chen, Heng-Yin; Ou-Yang, Yao; Lai, Jin-Shin; Kuo, Te-Son; Chong, Fok-Ching

    2005-01-01

    The purpose of this study is to develop a M3S- Based GPS navigation system for power wheelchair. The wheelchair steered with GPS and electronic compass can move automatically toward a specific destination through a GIS-Map in the computer. The topic of this study is to help people with disabilities regain independence of transportation in specific areas of their daily activities. This system is now designed to operate in special locations, for example, campuses or airports. Safety of the system is enhanced according to "M3S", which is an international standard for power wheelchair. In the proposed architecture, modules are easily and securely integrated to the wheelchair, which includes a tele-monitor system implemented with computer network, mobile-phone and physiological sensors. Bio-signals, wheelchair location and other information of the user are acquired by the nursing staff or any other medical personnel by using this system. PMID:17281122

  17. 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.

  18. 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

  19. 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

  20. 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

  1. 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., III; 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

  2. Stress drop and its Uncertainty for Earthquakes M3.8-5.5 in Central California and Oklahoma

    NASA Astrophysics Data System (ADS)

    Ding, Luyuan

    Stress drop is the stress that is effectively available to drive fault motion. It is a key parameter in predicting peak ground acceleration (PGA), since PGA∝, and it is very important in estimating ground motion. However, it is difficult to get an accurate estimation of stress drop. In order to get a more stable measurement of stress drop, we test two methods in this thesis: the first one is the Brune stress drop, which is more commonly applied, and the second one is the Arms stress drop, which less applied before and theoretically should have less uncertainty. By comparing these two methods we would like to test the feasibility and stability of the Arms method. We applied these two methods to data of earthquakes M3-5.5 in California and Oklahoma. We found that, taking Oklahoma results as an example, the mean value of Brune stress drop is 0.38 MPa, with a multiplicative uncertainty of 3.12, and the mean value of Arms stress drop is 1.04, with a multiplicative uncertainty of 1.79. Therefore we concluded that the Arms method is a good estimator of stress drop, with a smaller uncertainty. We determine the path attenuation so that we can increase the source-station distance of events studied to be as much as 76 km. The path seismic attenuation is a critical parameter that must be included in the analysis.

  3. Frustrated Lewis Pairs.

    PubMed

    Stephan, Douglas W

    2015-08-19

    The articulation of the notion of "frustrated Lewis pairs" (FLPs), which emerged from the discovery that H2 can be reversibly activated by combinations of sterically encumbered Lewis acids and bases, has prompted a great deal of recent activity. Perhaps the most remarkable consequence has been the development of FLP catalysts for the hydrogenation of a range of organic substrates. In the past 9 years, the substrate scope has evolved from bulky polar species to include a wide range of unsaturated organic molecules. In addition, effective stereoselective metal-free hydrogenation catalysts have begun to emerge. The mechanism of this activation of H2 has been explored, and the nature and range of Lewis acid/base combinations capable of effecting such activation have also expanded to include a variety of non-metal species. The reactivity of FLPs with a variety of other small molecules, including olefins, alkynes, and a range of element oxides, has also been developed. Although much of this latter chemistry has uncovered unique stoichiometric transformations, metal-free catalytic hydroamination, CO2 reduction chemistry, and applications in polymerization have also been achieved. The concept is also beginning to find applications in bioinorganic and materials chemistry as well as heterogeneous catalysis. This Perspective highlights many of these developments and discusses the relationship between FLPs and established chemistry. Some of the directions and developments that are likely to emerge from FLP chemistry in the future are also presented. PMID:26214241

  4. 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

  5. Parameter Invariance in the Rasch Model.

    ERIC Educational Resources Information Center

    Davison, Mark L.; Chen, Tsuey-Hwa

    This paper explores a logistic regression procedure for estimating item parameters in the Rasch model and testing the hypothesis of item parameter invariance across several groups/populations. Rather than using item responses directly, the procedure relies on "pseudo-paired comparisons" (PC) statistics defined over all possible pairs of items.…

  6. Controversies in kidney paired donation.

    PubMed

    Gentry, Sommer E; Montgomery, Robert A; Segev, Dorry L

    2012-07-01

    Kidney paired donation represented 10% of living kidney donation in the United States in 2011. National registries around the world and several separate registries in the United States arrange paired donations, although with significant variations in their practices. Concerns about ethical considerations, clinical advisability, and the quantitative effectiveness of these approaches in paired donation result in these variations. For instance, although donor travel can be burdensome and might discourage paired donation, it was nearly universal until convincing analysis showed that living donor kidneys can sustain many hours of cold ischemia time without adverse consequences. Opinions also differ about whether the last donor in a chain of paired donation transplants initiated by a nondirected donor should donate immediately to someone on the deceased donor wait-list (a domino or closed chain) or should be asked to wait some length of time and donate to start another sequence of paired donations later (an open chain); some argue that asking the donor to donate later may be coercive, and others focus on balancing the probability that the waiting donor withdraws versus the number of additional transplants if the chain can be continued. Other controversies in paired donation include simultaneous versus nonsimultaneous donor operations, whether to enroll compatible pairs, and interactions with desensitization protocols. Efforts to expand public awareness of and participation in paired donation are needed to generate more transplant opportunities. PMID:22732046

  7. Lone pairs: an electrostatic viewpoint.

    PubMed

    Kumar, Anmol; Gadre, Shridhar R; Mohan, Neetha; Suresh, Cherumuttathu H

    2014-01-16

    A clear-cut definition of lone pairs has been offered in terms of characteristics of minima in molecular electrostatic potential (MESP). The largest eigenvalue and corresponding eigenvector of the Hessian at the minima are shown to distinguish lone pair regions from the other types of electron localization (such as π bonds). A comparative study of lone pairs as depicted by various other scalar fields such as the Laplacian of electron density and electron localization function is made. Further, an attempt has been made to generalize the definition of lone pairs to the case of cations. PMID:24372481

  8. Methods for Identifying Pair Halos

    NASA Astrophysics Data System (ADS)

    Wells, Brendan; Caputo, Regina; Atwood, William; Ritz, Steven M.

    2016-01-01

    The flux of very high energy gamma rays from active galactic nuclei (AGN) is attenuated via interactions with extragalactic background photons and is converted into e+e- pairs. With non-zero intergalactic magnetic fields, the electrons and positrons will deflect as they propagate and simultaneously lose energy by upscattering cosmic microwave background photons. "Pair halos," the visible consequences of these electromagnetic cascades, are faint and difficult to observe against their AGN counterparts. We investigate three methods for indirectly identifying pair halos, using a two-component approach to model the AGN core/halo image. We estimate each method's sensitivity by utilizing a new, detailed Monte Carlo pair-halo simulation.

  9. Chaotic scattering of two vortex pairs

    NASA Astrophysics Data System (ADS)

    Tophøj, Laust; Aref, Hassan

    2008-11-01

    Chaotic scattering of two vortex pairs with slightly different circulations was considered by Eckhardt & Aref in 1988. A new numerical exploration suggests that the motion of two vortex pairs, with constituent vortices all of the same absolute circulation, also displays chaotic scattering regimes. The mechanisms leading to chaotic scattering are different from the ``slingshot effect'' identified by Price [Phys. Fluids A, 5, 2479 (1993)] and occur in a different region of the four-vortex phase space. They may in many cases be understood by appealing to the solutions of the three-vortex problem obtained by merging two like-signed vortices into one of twice the strength, and by assuming that the four-vortex problem has unstable, periodic solutions similar to those seen in the thereby associated three-vortex problems. The integrals of motion, linear impulse and Hamiltonian, are recast in a form appropriate for vortex pair scattering interactions that provides constraints on the parameters characterizing the outgoing vortex pairs in terms of the initial conditions.

  10. 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

  11. 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.

  12. Galactic Bridges in Pairs

    NASA Astrophysics Data System (ADS)

    Thierjung, Brianna; Jorge Moreno, Paul Torrey, Phil Hopkins

    2016-01-01

    We employ a suite of 75 simulations of galaxies in idealized major mergers to investigate the bridges formed by interactions. These simulations are based on the Feedback in Realistic Environments (FIRE) model (Hopkins et al. 2011). Moreover, unlike past work, we have both the resolution and diversity in merging orbits to make statistically meaningful predictions. We find that very dense, star forming bridges can be characterized as strong bridges. In particular, prograde mergers with high eccentricities and high impact parameters produce the most mass of stars in the bridge.

  13. X-ray spectroscopy of E2 and M3 transitions in Ni-like W

    SciTech Connect

    Clementson, J.; Beiersdorfer, P.; Gu, M. F.

    2010-01-15

    The electric quadrupole (E2) and magnetic octupole (M3) ground-state transitions in Ni-like W{sup 46+} have been measured using high-resolution crystal spectroscopy at the LLNL electron-beam ion trap facility. The lines fall in the soft x-ray region near 7.93 A and were originally observed as an unresolved feature in tokamak plasmas. Using flat ammonium dihydrogen phosphate and quartz crystals, the wavelengths, intensities, and polarizations of the two lines have been measured for various electron-beam energies and compared to intensity and polarization calculations performed using the Flexible Atomic Code (FAC).

  14. X-ray Spectroscopy of E2 and M3 Transitions in Ni-like W

    SciTech Connect

    Clementson, J; Beiersdorfer, P; Gu, M F

    2009-11-09

    The electric quadrupole (E2) and magnetic octupole (M3) ground state transitions in Ni-like W{sup 46+} have been measured using high-resolution crystal spectroscopy at the Livermore electron beam ion trap facility. The lines fall in the soft x-ray region near 7.93 {angstrom} and were originally observed as an unresolved feature in tokamak plasmas. Using flat ADP and quartz crystals the wavelengths, intensities, and polarizations of the two lines have been measured for various electron beam energies and compared to intensity and polarization calculations performed using the Flexible Atomic Code (FAC).

  15. 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

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

    PubMed

    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 (microMLC). 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 microMLC transmission and interleaf leakage. Simulations and measurements to obtain microMLC 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 microMLC device. PMID:20702922

  17. 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.

  18. Pair Programming: Issues and Challenges

    NASA Astrophysics Data System (ADS)

    Lui, Kim Man; Barnes, Kyle Atikus; Chan, Keith C. C.

    Pair programming, two programmers collaborating on design, coding and testing, has been a controversial focus of interest as Agile Software Development continues to grow in popularity both among academics and practitioners. As a result of the many investigations into the effectiveness of pair programming in the last decade, many have come to realize that there are many hard-to-control factors in pair programming in particular and in empirical software engineering in general. Because of these factors, the results of many pair programming experiments are not easy to replicate and the relative productivity of pair and solo programming are still not fully understood. So far, it has been concluded by previous studies that pair programming productivity can vary, but few have shown how and why this is the case. In this chapter, we discuss a number of challenging factors in the adoption of pair programming and present an approach to deal with them. We discuss how different factors may affect our experimental outcomes and improve experiment design to reveal how and why pair programming can be made productive, at least, in controlled situations.

  19. 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…

  20. M1-M3 muscarinic acetylcholine receptor-deficient mice: novel phenotypes.

    PubMed

    Gautam, Dinesh; Duttaroy, Alokesh; Cui, Yinghong; Han, Sung-Jun; Deng, Chuxia; Seeger, Thomas; Alzheimer, Christian; Wess, Jürgen

    2006-01-01

    The five muscarinic acetylcholine receptors (M1-M5 mAChRs) mediate a very large number of important physiological functions (Caulfield, 1993; Caulfield and Birdsall, 1998; Wess, 2004). Because of the lack of small molecule ligands endowed with a high degree of receptor subtype selectivity and the fact that most tissues or cell types express two or more mAChR subtypes, identification of the physiological and pathophysiological roles of the individual mAChR subtypes has proved to be a challenging task. To overcome these difficulties, we recently generated mutant mouse lines deficient in each of the five mAChR genes (M1R-/- mice, M2R-/- mice, M3R-/- mice, etc. [Wess, 2004]). Phenotyping studies showed that each of the five mutant mouse lines displayed characteristic physiological, pharmacological, behavioral, biochemical, or neurochemical deficits (Wess, 2004). This chapter summarizes recent findings dealing with the importance of the M2mAChR for cognitive processes and the roles of the M1 and M3 mAChRs in mediating stimulation of glandular secretion. PMID:17192665

  1. 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.

  2. 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

  3. M3D: a kernel-based test for spatially correlated changes in methylation profiles

    PubMed Central

    Mayo, Tom R.; Schweikert, Gabriele; Sanguinetti, Guido

    2015-01-01

    Motivation: DNA methylation is an intensely studied epigenetic mark implicated in many biological processes of direct clinical relevance. Although sequencing-based technologies are increasingly allowing high-resolution measurements of DNA methylation, statistical modelling of such data is still challenging. In particular, statistical identification of differentially methylated regions across different conditions poses unresolved challenges in accounting for spatial correlations within the statistical testing procedure. Results: We propose a non-parametric, kernel-based method, M3D, to detect higher order changes in methylation profiles, such as shape, across pre-defined regions. The test statistic explicitly accounts for differences in coverage levels between samples, thus handling in a principled way a major confounder in the analysis of methylation data. Empirical tests on real and simulated datasets show an increased power compared to established methods, as well as considerable robustness with respect to coverage and replication levels. Availability and implementation: R/Bioconductor package M3D. Contact: G.Sanguinetti@ed.ac.uk Supplementary information: Supplementary data are available at Bioinformatics online. PMID:25398611

  4. 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.

  5. 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.

  6. Resonant tunneling of fluctuation Cooper pairs

    DOE PAGESBeta

    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

  7. Supernovae in paired host galaxies

    NASA Astrophysics Data System (ADS)

    Nazaryan, T. A.; Petrosian, A. R.; Hakobyan, A. A.; Adibekyan, V. Zh.; Kunth, D.; Mamon, G. A.; Turatto, M.; Aramyan, L. S.

    2014-12-01

    We investigate the influence of close neighbor galaxies on the properties of supernovae (SNe) and their host galaxies using 56 SNe located in pairs of galaxies with different levels of star formation (SF) and nuclear activity. The mean distance of type II SNe from nuclei of hosts is greater by about a factor of 2 than that of type Ibc SNe. For the first time it is shown that SNe Ibc are located in pairs with significantly smaller difference of radial velocities between components than pairs containing SNe Ia and II. We consider this as a result of higher star formation rate (SFR) of these closer systems of galaxies. SN types are not correlated with the luminosity ratio of host and neighbor galaxies in pairs. The orientation of SNe with respect to the preferred direction toward neighbor galaxy is found to be isotropic and independent of kinematical properties of the galaxy pair.

  8. Property (RD) for Hecke Pairs

    NASA Astrophysics Data System (ADS)

    Shirbisheh, Vahid

    2012-06-01

    As the first step towards developing noncommutative geometry over Hecke C ∗-algebras, we study property (RD) (Rapid Decay) for Hecke pairs. When the subgroup H in a Hecke pair ( G, H) is finite, we show that the Hecke pair ( G, H) has (RD) if and only if G has (RD). This provides us with a family of examples of Hecke pairs with property (RD). We also adapt Paul Jolissant's works in Jolissaint (J K-Theory 2:723-735, 1989; Trans Amer Math Soc 317(1):167-196, 1990) to the setting of Hecke C ∗-algebras and show that when a Hecke pair ( G, H) has property (RD), the algebra of rapidly decreasing functions on the set of double cosets is closed under holomorphic functional calculus of the associated (reduced) Hecke C ∗-algebra. Hence they have the same K 0-groups.

  9. 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.

  10. 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

  11. 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

  12. Muscarinic M3 receptors on structural cells regulate cigarette smoke-induced neutrophilic airway inflammation in mice

    PubMed Central

    van Os, Ronald P.; Dethmers-Ausema, Albertina; Bos, I. Sophie T.; Hylkema, Machteld N.; van den Berge, Maarten; Hiemstra, Pieter S.; Wess, Jürgen; Meurs, Herman; Kerstjens, Huib A. M.; Gosens, Reinoud

    2014-01-01

    Anticholinergics, blocking the muscarinic M3 receptor, are effective bronchodilators for patients with chronic obstructive pulmonary disease. Recent evidence from M3 receptor-deficient mice (M3R−/−) indicates that M3 receptors also regulate neutrophilic inflammation in response to cigarette smoke (CS). M3 receptors are present on almost all cell types, and in this study we investigated the relative contribution of M3 receptors on structural cells vs. inflammatory cells to CS-induced inflammation using bone marrow chimeric mice. Bone marrow chimeras (C56Bl/6 mice) were generated, and engraftment was confirmed after 10 wk. Thereafter, irradiated and nonirradiated control animals were exposed to CS or fresh air for four consecutive days. CS induced a significant increase in neutrophil numbers in nonirradiated and irradiated control animals (4- to 35-fold). Interestingly, wild-type animals receiving M3R−/− bone marrow showed a similar increase in neutrophil number (15-fold). In contrast, no increase in the number of neutrophils was observed in M3R−/− animals receiving wild-type bone marrow. The increase in keratinocyte-derived chemokine (KC) levels was similar in all smoke-exposed groups (2.5- to 5.0-fold). Microarray analysis revealed that fibrinogen-α and CD177, both involved in neutrophil migration, were downregulated in CS-exposed M3R−/− animals receiving wild-type bone marrow compared with CS-exposed wild-type animals, which was confirmed by RT-qPCR (1.6–2.5 fold). These findings indicate that the M3 receptor on structural cells plays a proinflammatory role in CS-induced neutrophilic inflammation, whereas the M3 receptor on inflammatory cells does not. This effect is probably not mediated via KC release, but may involve altered adhesion and transmigration of neutrophils via fibrinogen-α and CD177. PMID:25381025

  13. 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.

  14. Ion Pair-π Interactions.

    PubMed

    Fujisawa, Kaori; Humbert-Droz, Marie; Letrun, Romain; Vauthey, Eric; Wesolowski, Tomasz A; Sakai, Naomi; Matile, Stefan

    2015-09-01

    We report that anion-π and cation-π interactions can occur on the same aromatic surface. Interactions of this type are referred to as ion pair-π interactions. Their existence, nature, and significance are elaborated in the context of spectral tuning, ion binding in solution, and activation of cell-penetrating peptides. The origin of spectral tuning by ion pair-π interactions is unraveled with energy-minimized excited-state structures: The solvent- and pH-independent red shift of absorption and emission of push-pull fluorophores originates from antiparallel ion pair-π attraction to their polarized excited state. In contrast, the complementary parallel ion pair-π repulsion is spectroscopically irrelevant, in part because of charge neutralization by intriguing proton and electron transfers on excited push-pull surfaces. With time-resolved fluorescence measurements, very important differences between antiparallel and parallel ion pair-π interactions are identified and quantitatively dissected from interference by aggregation and ion pair dissociation. Contributions from hydrogen bonding, proton transfer, π-π interactions, chromophore twisting, ion pairing, and self-assembly are systematically addressed and eliminated by concise structural modifications. Ion-exchange studies in solution, activation of cell-penetrating peptides in vesicles, and computational analysis all imply that the situation in the ground state is complementary to spectral tuning in the excited state; i.e., parallel rather than antiparallel ion pair-π interactions are preferred, despite repulsion from the push-pull dipole. The overall quite complete picture of ion pair-π interactions provided by these remarkably coherent yet complex results is expected to attract attention throughout the multiple disciplines of chemistry involved. PMID:26291550

  15. 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.

  16. 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

  17. 4 Draconis - A unique triple system containing an M3 giant and a cataclysmic binary

    NASA Technical Reports Server (NTRS)

    Reimers, D.; Griffin, R. F.; Brown, A.

    1988-01-01

    The M3 III giant 4 Dra has a UV bright companion discovered with IUE as a probable cataclysmic variable (CV). The orbit of the M giant around the center of gravity of the system that it forms with the cataclysmic binary is determined. 4 Dra B shows spectrum variations like a CV; the photometric period is 3 h 58.5 m + or - 1 m is determined. 4 Dra B is the first CV for which an independent distance estimate can be given from the spectroscopic parallax of the companion. Properties of the CV, which is probably of the magnetic type (AM Her), are briefly discussed. The age of the CV may be less than 100 million yr.

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

    NASA Astrophysics Data System (ADS)

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

    2014-09-01

    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.

  19. M3D-K Simulations of Sawteeth and Energetic Particle Transport in Tokamak Plasmas

    NASA Astrophysics Data System (ADS)

    Shen, Wei; Fu, Guoyong; Sheng, Zhengmao; Breslau, Joshua; Wang, Feng

    2013-10-01

    Nonlinear simulations of Sawteeth and energetic particle transport are carried out using the kinetic/MHD hybrid code M3D-K. MHD simulations show repeated sawtooth cycles due to a resistive (1,1) internal kink mode 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 plasma core depending on pitch angle and energy. For trapped particles, the redistribution occurs for particle energy below a critical value in agreement with previous theory. For co-passing particles, the redistribution is strong with little dependence on particle energy. In contrast, the redistribution level of counter-passing particles decreases as particle energy becomes large.

  20. 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.

  1. A Swift/UVOT NUV Study of RR Lyrae Stars in the Globular Cluster M3

    NASA Astrophysics Data System (ADS)

    Porterfield, Blair; Siegel, M.; Swift; UVOT

    2014-01-01

    We present the first results of a program to monitor RR Lyrae stars in globular clusters with the Swift Ultraviolet Optical Telescope. Although variable stars have their strongest pulsations in the UV, no comprehensive catalog of NUV light curves has ever been produced for RR Lyrae stars. We present uvm2 light curves for 124 variable star candidates in the globular cluster M3. We show that the RR Lyrae stars have strong pulsations in the NUV, with amplitudes up to three magnitudes. We show that the RR Lyrae follow period-amplitude relations in the NUV similar to those they follow in the optical. Our data hint at the existence of a period-metallicity-luminosity relationship in the UV that would make RR Lyrae even more useful standard candles.

  2. Analysis of power spectral density as a performance metric for TMT M3

    NASA Astrophysics Data System (ADS)

    Yang, Fei; An, Qi-Chang; Wang, Fu-Guo; Liu, Xiang-Yi

    2014-09-01

    We investigate a new metric power spectral density (PSD),for characterizing the performance of seeing-limited large telescope such as thirty meter telescope(TMT ). As the PSD is directly related to the performance of the atmosphere which plays an important role in ground based facilities, it represents the efficiency lose due to mid and high-spatial frequency components in observing time. The metric also properly counts for the optic error of the mirror itself such as the deviations from a perfect surface, and metrology measurement errors .The metric can multiply all the errors which differentiates from the traditional ones, such as RMS. We also numerically confirm this feature for Karman model atmosphere error multiplied with the sample of our vendor and the TMT M3.Additonaly, we discuss other pertinent feature of the PSD, including its relationship to Zernike aberration ,and RMS of wave front errors.

  3. Integrated modeling and dynamics simulation for the TMT-M3 control system

    NASA Astrophysics Data System (ADS)

    Deng, Yong-ting; Li, Hong-wen; Yang, Fei; Wang, Jian-li; Su, Yan-qin; Zhao, Hong-chao

    2014-09-01

    In order to analyze the tracking performance and design the controllers for TMT-M3 control system in the design stage. This paper presents the development of the analytical model of the gear driven large telescope using the lumped mass modeling method. The analytical model includes the telescope structure, its drives, the velocity loop and position loop. First, the modal model of a flexible structure is analyzed based on the finite-element data. And the modal model is transferred into the state-space model, in continuous-time. Next, the drive model is derived, and combined into the velocity loop and position loop. Finally, the impact of the error sources on the control loop properties is simulated. According to the simulation accuracy of the analytical modeling, the analytical model can be used in implementation, such as the model-based controllers.

  4. 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.

  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. 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.

  7. 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.

  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. 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.

  10. 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)...

  11. Chemokine Binding Protein M3 of Murine Gammaherpesvirus 68 Modulates the Host Response to Infection in a Natural Host

    PubMed Central

    Hughes, David J.; Kipar, Anja; Leeming, Gail H.; Bennett, Elaine; Howarth, Deborah; Cummerson, Joanne A.; Papoula-Pereira, Rita; Flanagan, Brian F.; Sample, Jeffery T.; Stewart, James P.

    2011-01-01

    Murine γ-herpesvirus 68 (MHV-68) infection of Mus musculus-derived strains of mice is an attractive model of γ-herpesvirus infection. Surprisingly, however, ablation of expression of MHV-68 M3, a secreted protein with broad chemokine-binding properties in vitro, has no discernable effect during experimental infection via the respiratory tract. Here we demonstrate that M3 indeed contributes significantly to MHV-68 infection, but only in the context of a natural host, the wood mouse (Apodemus sylvaticus). Specifically, M3 was essential for two features unique to the wood mouse: virus-dependent inducible bronchus-associated lymphoid tissue (iBALT) in the lung and highly organized secondary follicles in the spleen, both predominant sites of latency in these organs. Consequently, lack of M3 resulted in substantially reduced latency in the spleen and lung. In the absence of M3, splenic germinal centers appeared as previously described for MHV-68-infected laboratory strains of mice, further evidence that M3 is not fully functional in the established model host. Finally, analyses of M3's influence on chemokine and cytokine levels within the lungs of infected wood mice were consistent with the known chemokine-binding profile of M3, and revealed additional influences that provide further insight into its role in MHV-68 biology. PMID:21445235

  12. Chemokine binding protein M3 of murine gammaherpesvirus 68 modulates the host response to infection in a natural host.

    PubMed

    Hughes, David J; Kipar, Anja; Leeming, Gail H; Bennett, Elaine; Howarth, Deborah; Cummerson, Joanne A; Papoula-Pereira, Rita; Flanagan, Brian F; Sample, Jeffery T; Stewart, James P

    2011-03-01

    Murine γ-herpesvirus 68 (MHV-68) infection of Mus musculus-derived strains of mice is an attractive model of γ-herpesvirus infection. Surprisingly, however, ablation of expression of MHV-68 M3, a secreted protein with broad chemokine-binding properties in vitro, has no discernable effect during experimental infection via the respiratory tract. Here we demonstrate that M3 indeed contributes significantly to MHV-68 infection, but only in the context of a natural host, the wood mouse (Apodemus sylvaticus). Specifically, M3 was essential for two features unique to the wood mouse: virus-dependent inducible bronchus-associated lymphoid tissue (iBALT) in the lung and highly organized secondary follicles in the spleen, both predominant sites of latency in these organs. Consequently, lack of M3 resulted in substantially reduced latency in the spleen and lung. In the absence of M3, splenic germinal centers appeared as previously described for MHV-68-infected laboratory strains of mice, further evidence that M3 is not fully functional in the established model host. Finally, analyses of M3's influence on chemokine and cytokine levels within the lungs of infected wood mice were consistent with the known chemokine-binding profile of M3, and revealed additional influences that provide further insight into its role in MHV-68 biology. PMID:21445235

  13. 75 FR 3471 - International Conference on Harmonisation; Guidance on M3(R2) Nonclinical Safety Studies for the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-21

    ... HUMAN SERVICES Food and Drug Administration International Conference on Harmonisation; Guidance on M3(R2... Pharmaceuticals; Availability AGENCY: Food and Drug Administration, HHS. ACTION: Notice. SUMMARY: The Food and Drug Administration (FDA) is announcing the availability of a guidance entitled ``M3(R2)...

  14. 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. PMID:26666184

  15. 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

  16. Pairing in hot rotating nuclei

    SciTech Connect

    Hung, N. Quang; Dang, N. Dinh

    2008-12-15

    Nuclear pairing properties are studied within an approach that includes the quasiparticle-number fluctuation (QNF) and coupling to the quasiparticle-pair vibrations at finite temperature and angular momentum. The formalism is developed to describe noncollective rotations about the symmetry axis. The numerical calculations are performed within a doubly folded equidistant multilevel model as well as several realistic nuclei. The results obtained for the pairing gap, total energy, and heat capacity show that the QNF smoothes out the sharp SN phase transition and leads to the appearance of a thermally assisted pairing gap in rotating nuclei at finite temperature. The corrections due to the dynamic coupling to SCQRPA vibrations and particle-number projection are analyzed. The effect of backbending of the momentum of inertia as a function of squared angular velocity is also discussed.

  17. 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.

  18. Cooper pairing in non-Fermi liquids

    NASA Astrophysics Data System (ADS)

    Metlitski, Max A.; Mross, David F.; Sachdev, Subir; Senthil, T.

    2015-03-01

    States of matter with a sharp Fermi surface but no well-defined Landau quasiparticles arise in a number of physical systems. Examples include (i) quantum critical points associated with the onset of order in metals; (ii) spinon Fermi-surface [U(1) spin-liquid] state of a Mott insulator; (iii) Halperin-Lee-Read composite fermion charge liquid state of a half-filled Landau level. In this work, we use renormalization group techniques to investigate possible instabilities of such non-Fermi liquids in two spatial dimensions to Cooper pairing. We consider the Ising-nematic quantum critical point as an example of an ordering phase transition in a metal, and demonstrate that the attractive interaction mediated by the order-parameter fluctuations always leads to a superconducting instability. Moreover, in the regime where our calculation is controlled, superconductivity preempts the destruction of electronic quasiparticles. On the other hand, the spinon Fermi surface and the Halperin-Lee-Read states are stable against Cooper pairing for a sufficiently weak attractive short-range interaction; however, once the strength of attraction exceeds a critical value, pairing sets in. We describe the ensuing quantum phase transition between (i) U(1 ) and Z2 spin-liquid states; (ii) Halperin-Lee-Read and Moore-Read states.

  19. 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

  20. Role of M3 protein in the adherence and internalization of an invasive Streptococcus pyogenes strain by epithelial cells.

    PubMed

    Eyal, Osnat; Jadoun, Jeries; Bitler, Arcady; Skutelski, Ehud; Sela, Shlomo

    2003-10-15

    Streptococcus pyogenes utilizes multiple mechanisms for adherence to and internalization by epithelial cells. One of the molecules suggested of being involved in adherence and internalization is the M protein. Although strains of the M3 serotype form the second largest group isolated from patients with severe invasive diseases and fatal infections, not much information is known regarding the interactions of M3 protein with mammalian cells. In this study we have constructed an emm3 mutant of an invasive M3 serotype (SP268), and demonstrated that the M3 protein is involved in both adherence to and internalization by HEp-2 cells. Fibronectin promoted both adherence and internalization of SP268 in an M3-independent pathway. Utilizing speB and speB/emm3 double mutants, it was found that M3 protein is not essential for the maturation of SpeB, as was reported for the M1 protein. Increased internalization efficiency observed in both the speB and emm3/speB mutants suggested that inhibition of S. pyogenes internalization by SpeB is not related to the presence of an intact M3 protein. Thus, other proteins in SP268, which serve as targets for SpeB activity, have a prominent role in the internalization process. PMID:14522456

  1. Altered ultrastructure, density and cathepsin K expression in bone of female muscarinic acetylcholine receptor M3 knockout mice.

    PubMed

    Lips, Katrin Susanne; Kneffel, Mathias; Willscheid, Fee; Mathies, Frank Martin; Kampschulte, Marian; Hartmann, Sonja; Panzer, Imke; Dürselen, Lutz; Heiss, Christian; Kauschke, Vivien

    2015-11-01

    High frequency of osteoporosis is found in postmenopausal women where several molecular components were identified to be involved in bone loss that subsequently leads to an increased fracture risk. Bone loss has already been determined in male mice with gene deficiency of muscarinic acetylcholine receptor M3 (M3R-KO). Here we asked whether bone properties of female 16-week old M3R-KO present similarities to osteoporotic bone loss by means of biomechanical, radiological, electron microscopic, cell- and molecular biological methods. Reduced biomechanical strength of M3R-KO correlated with cortical thickness and decreased bone mineral density (BMD). Femur and vertebrae of M3R-KO demonstrated a declined trabecular bone volume, surface, and a higher trabecular pattern factor and structure model index (SMI) compared to wild type (WT) mice. In M3R-KO, the number of osteoclasts as well as the cathepsin K mRNA expression was increased. Osteoclasts of M3R-KO showed an estimated increase in cytoplasmic vesicles. Further, histomorphometrical analysis revealed up-regulation of alkaline phosphatase. Osteoblasts and osteocytes showed a swollen cytoplasm with an estimated increase in the amount of rough endoplasmatic reticulum and in case of osteocytes a reduced pericellular space. Thus, current results on bone properties of 16-week old female M3R-KO are related to postmenopausal osteoporotic phenotype. Stimulation and up-regulation of muscarinic acetylcholine receptor subtype M3 expression in osteoblasts might be a possible new option for prevention and therapy of osteoporotic fractures. Pharmacological interventions and the risk of side effects have to be determined in upcoming studies. PMID:26002583

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. Mass of Galaxies in Pairs

    NASA Astrophysics Data System (ADS)

    Junqueira, S.; Chan, R.

    We have compared the frequency distribution of the dynamical observed quantity log (V r), for a sample of 46 pairs of elliptical galaxies, to the distribution of this quantity obtained from numerical simulations of pairs of galaxies. From such an analysis, where we have considered the structure of the galaxies and its influence in the orbital evolution of the system, we have obtained the characteristic mass and the mass-luminosity ratio for the sample. Our results show that the hypothesis of point-mass in elliptical orbits is, for this sample, an approximation as good as the model that takes into account the structure of the galaxies. The statistical method used here gives an estimate of a more reliable mass, it minimizes the contamination of spurious pairs and it considers adequately the contribution of the physical pairs. We have obtained a characteristic mass to the 46 elliptical pairs of 1.68 × 10^12 +/- 7.01 × 10^11 M_solar with M/L = 17.6 +/- 7.3 (H_0 = 60 km s^-1 Mpc^-1).

  7. Mineralogy of Mare Serenitatis on the near side of the Moon based on Chandrayaan-1 Moon Mineralogy Mapper (M3) observations

    NASA Astrophysics Data System (ADS)

    Kaur, Prabhjot; Bhattacharya, Satadru; Chauhan, Prakash; Ajai; Kiran Kumar, A. S.

    2013-01-01

    Spectral analysis of Mare Serenitatis has been carried out using Chandrayaan-1 Moon Mineralogy Mapper (M3) data in order to map the compositional diversity of the basaltic units that exist in the basin. Mare Serenitatis is characterized by multiple basaltic flows of different ages indicating a prolonged volcanism subsequent to the basin formation event. Reflectance spectra of fresh craters from the Mare Serenitatis have been analyzed to study the nature and location of the spectral absorption features around 1- and 2-μm respectively, arising due to the electronic charge transition of Fe2+ in the crystal lattice of pyroxenes and/or olivine. Chandrayaan-1 M3 data have been utilized to obtain an Integrated Band Depth (IBD) mosaic of the Serenitatis basin. Based on the spectral variations observed in the IBD mosaic, 13 spectral units have been mapped in the Mare Serenitatis. In the present study, we have also derived spectral band parameters, namely, band center, band strength, band area and band area ratio from the M3 data to study the mineralogical and compositional variations amongst the basaltic units of the studied basin. On the basis of spectral band parameter analysis, the pyroxene compositions of the basaltic units have been determined, which vary from low to intermediate end of the high-Ca pyroxene and probably represent a sub-calcic to calcic augite compositional range. Detailed spectral analyses reveal little variations in the mafic mineralogy of the mare basalts in terms of pyroxene chemistry. The uniformity in pyroxene composition across the basaltic units of Mare Serenitatis, therefore, suggest a probably stable basaltic source region, which might not have experienced large-scale fractionation during the prolonged volcanism that resulted in filling of the large Serenitatis basin.

  8. 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.

  9. 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

  10. 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.

  11. Comparison of the activation kinetics of the M3 acetylcholine receptor and a constitutively active mutant receptor in living cells.

    PubMed

    Hoffmann, Carsten; Nuber, Susanne; Zabel, Ulrike; Ziegler, Nicole; Winkler, Christiane; Hein, Peter; Berlot, Catherine H; Bünemann, Moritz; Lohse, Martin J

    2012-08-01

    Activation of G-protein-coupled receptors is the first step of the signaling cascade triggered by binding of an agonist. Here we compare the activation kinetics of the G(q)-coupled M(3) acetylcholine receptor (M(3)-AChR) with that of a constitutively active mutant receptor (M(3)-AChR-N514Y) using M(3)-AChR constructs that report receptor activation by changes in the fluorescence resonance energy transfer (FRET) signal. We observed a leftward shift in the concentration-dependent FRET response for acetylcholine and carbachol with M(3)-AChR-N514Y. Consistent with this result, at submaximal agonist concentrations, the activation kinetics of M(3)-AChR-N514Y were significantly faster, whereas at maximal agonist concentrations the kinetics of receptor activation were identical. Receptor deactivation was significantly faster with carbachol than with acetylcholine and was significantly delayed by the N514Y mutation. Receptor-G-protein interaction was measured by FRET between M(3)-AChR-yellow fluorescent protein (YFP) and cyan fluorescent protein (CFP)-Gγ(2). Agonist-induced receptor-G-protein coupling was of a time scale similar to that of receptor activation. As observed for receptor deactivation, receptor-G-protein dissociation was slower for acetylcholine than that for carbachol. Acetylcholine-stimulated increases in receptor-G-protein coupling of M(3)-AChR-N514Y reached only 12% of that of M(3)-AChR and thus cannot be kinetically analyzed. G-protein activation was measured using YFP-tagged Gα(q) and CFP-tagged Gγ(2). Activation of G(q) was significantly slower than receptor activation and indistinguishable for the two agonists. However, G(q) deactivation was significantly prolonged for acetylcholine compared with that for carbachol. Consistent with decreased agonist-stimulated coupling to G(q), agonist-stimulated G(q) activation by M(3)-AChR-N514Y was not detected. Taken together, these results indicate that the N514Y mutation produces constitutive activation of M(3

  12. Separable pairing force for relativistic quasiparticle random-phase approximation

    SciTech Connect

    Tian Yuan; Ma Zhongyu; Ring, Peter

    2009-06-15

    We have introduced a separable pairing force, which was adjusted to reproduce the pairing properties of the Gogny force in nuclear matter. This separable pairing force is able to describe in relativistic Hartree-Bogoliubov (RHB) calculations the pairing properties in the ground state of finite nuclei on almost the same footing as the original Gogny interaction. In this work we investigate excited states using the Relativistic Quasiparticle Random-Phase Approximation (RQRPA) with the same separable pairing force. For consistency the Goldstone modes and the convergence with various cutoff parameters in this version of RQRPA are studied. The first excited 2{sup +} states for the chain of Sn isotopes with Z=50 and the chain of isotones with N=82 isotones are calculated in RQRPA together with the 3{sup -} states of Sn isotopes. By comparing our results with experimental data and with the results of the original Gogny force we find that this simple separable pairing interaction is very successful in depicting the pairing properties of vibrational excitations.

  13. Stereo pairs from linear morphing

    NASA Astrophysics Data System (ADS)

    McAllister, David F.

    1998-04-01

    Several authors have recently investigated the ability to compute intermediate views of a scene using given 2D images from arbitrary camera positions. The methods fall under the topic of image based rendering. In the case we give here, linear morphing between two parallel views of a scene produces intermediate views that would have been produced by parallel movement of a camera. Hence, the technique produces images computed in a way that is consistent with the standard off-axis perspective projection method for computing stereo pairs. Using available commercial 2D morphing software, linear morphing can be used to produce stereo pairs from a single image with bilateral symmetry such as a human face. In our case, the second image is produced by horizontal reflection. We describe morphing and show how it can be used to provide stereo pairs from single images.

  14. 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.

  15. Pairing effects in nuclear dynamic

    NASA Astrophysics Data System (ADS)

    Lacroix, Denis; Scamps, Guillaume; Tanimura, Yusuke

    2016-05-01

    In recent years, efforts have been made to account for super-fluidity in time-dependent mean-field description of nuclear dynamic [1-5]. Inclusion of pairing is important to achieve a realistic description of static properties of nuclei. Here,we show that pairing can also affect the nuclear motion. State of the art TDHF approach can describe from small to large amplitude collective motion as well as the collision between nuclei. Very recently, this microscopic approach has been improved to include pairing either in the BCS or HFB framework. Recent applications of the 3D TDHF + BCS (TDHF+BCS) model introduced in [4] will be presented. The role of super-fluidity on collective motion [6, 7], on one- and two-particle transfer [8] and on fission [9, 10] will be illustrated.

  16. C. Y. Chao, Pair Creation and Pair Annihilation

    NASA Astrophysics Data System (ADS)

    Li, Bing An; Yang, C. N.

    C. Y. Chao's contribution to physicists' acceptance of QED in 1933-1934 through his experiments of 1930 is analyzed. It is pointed out that Blackett and Occhialini's key suggestion of 1933 about hole theory was based on identifying Chao's "additional scattered rays" (1930) as due to pair annihilation.

  17. C. Y. Chao, Pair Creation and Pair Annihilation

    NASA Astrophysics Data System (ADS)

    Li, Bing An; Yang, C. N.

    2013-05-01

    C. Y. Chao's contribution to physicists' acceptance of QED in 1933-1934 through his experiments of 1930 is analyzed. It is pointed out that Blackett and Occhialini's key suggestion of 1933 about hole theory was based on identifying Chao's "additional scattered rays" (1930) as due to pair annihilation.

  18. 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.

  19. Invisibly Sanitizable Signature without Pairings

    NASA Astrophysics Data System (ADS)

    Yum, Dae Hyun; Lee, Pil Joong

    Sanitizable signatures allow sanitizers to delete some pre-determined parts of a signed document without invalidating the signature. While ordinary sanitizable signatures allow verifiers to know how many subdocuments have been sanitized, invisibly sanitizable signatures do not leave any clue to the sanitized subdocuments; verifiers do not know whether or not sanitizing has been performed. Previous invisibly sanitizable signature scheme was constructed based on aggregate signature with pairings. In this article, we present the first invisibly sanitizable signature without using pairings. Our proposed scheme is secure under the RSA assumption.

  20. Nucleon pairing in Sn isotopes

    NASA Astrophysics Data System (ADS)

    Imasheva, L.; Ishkhanov, B.; Stepanov, M.; Tretyakova, T.

    2016-01-01

    The systematics of excited states in Sn isotopes are discussed on basis of pairing interaction in nuclei. Nucleon paring leads to formation of excited states multiplets. The estimation of multiplet splitting based on experimental nuclear masses allows one to calculate the position of excited states with different seniority in δ-approximation. The wide systematics of the spectra of Sn isotopes gives a possibility to check the pairing interaction for different subshells and consider the multiplets of excited states in the neutron-rich isotopes far from stability.

  1. Negative refractive index of metallic cross-I-shaped pairs: origin and evolution with pair gap width.

    PubMed

    Ma, Y G; Wang, X C; Ong, C K

    2008-07-01

    A structured composite of the negative index of refraction was fabricated by one layer of cross-I-shaped metal pairs. In this structure, the electric and magnetic inclusions were effectively integrated into one small unit. We varied the spacing of the cross pair to control the location of the magnetic resonance mode and their intercoupling with the electric mode. The frequency dependences of permittivity, permeability, and refractive indices with different gap widths of the pairs were systematically discussed by free-space measurement as well as numerical simulation. A spacing window dependent on the geometrical parameters was found in which the real part of the refractive index could have a negative value. The one-layer cross-pair pattern proposed in this work can be extended to three-dimensional structures with well-controlled interlayer coupling that will greatly facilitate the fabrication and measurement of negative-index materials in high frequencies. PMID:18764072

  2. 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.

  3. Missing energies at pair creation

    NASA Technical Reports Server (NTRS)

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

    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.

  4. 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…

  5. 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…

  6. Paired Reading: Psycholinguistics in Practice.

    ERIC Educational Resources Information Center

    Barrett, James Martin

    1987-01-01

    Contends that children need to learn phonic skills, not necessarily through early direct teaching, but through reading experience. Suggests using Paired Reading, which is validated by psycholinguistic reading theory and provides opportunities to learn to read from context and use innate syntactic and semantic knowledge. (SKC)

  7. 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.

  8. 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

  9. 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

  10. 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

  11. Spin-1 Heisenberg ferromagnet using pair approximation method

    NASA Astrophysics Data System (ADS)

    Mert, Murat; Kılıç, Ahmet; Mert, Gülistan

    2016-06-01

    Thermodynamic properties for Heisenberg ferromagnet with spin-1 on the simple cubic lattice have been calculated using pair approximation method. We introduce the single-ion anisotropy and the next-nearest-neighbor exchange interaction. We found that for negative single-ion anisotropy parameter, the internal energy is positive and heat capacity has two peaks.

  12. 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

  13. 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

  14. 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

  15. Pseudopotential theory of interacting roton pairs in superfluid 4He

    NASA Astrophysics Data System (ADS)

    Bedell, K.; Pines, D.; Zawadowski, A.

    1984-01-01

    A configuration-space pseudopotential, which is closely related to that used by Aldrich and Pines to describe the effective interaction between background particles in 3He and 4He, is constructed and used to calculate the roton-roton scattering amplitude. From that amplitude we obtain a theory that is completely congruent with the roton-liquid theory of Bedell, Pines, and Fomin. We calculate two-roton bound states, roton-liquid parameters, and roton lifetimes, as well as information about the hybridization of the two-roton bound state with excitations of higher and lower energy. Excellent agreement between theory and experiment is obtained for the l=2 bound state at zero pair momentum, the roton lifetime, the roton contribution to the normal-fluid viscosity and the normal-fluid density, and the temperature variation of the roton energy. The effective roton-roton coupling parameters at large pair momentum are found to be an order of magnitude larger than those for small or vanishing pair momentum. At SVP we find that a substantial number of two-roton bound states of varying symmetry exist for pair momentum up to ~ 3 Å -1; at standard pressure, however the roton-roton interaction for momenta ~ 1 Å -1 is found to become repulsive, so that both the l=2 bound state at zero pair momentum and bound states at intermediate momenta are predicted to disappear under pressure.

  16. Meeting Report: “Metagenomics, Metadata and Meta-analysis” (M3) Special Interest Group at ISMB 2009

    PubMed Central

    Field, Dawn; Friedberg, Iddo; Sterk, Peter; Kottmann, Renzo; Glöckner, Frank Oliver; Hirschman, Lynette; Garrity, George M.; Cochrane, Guy; Wooley, John; Gilbert, Jack

    2009-01-01

    This report summarizes the proceedings of the “Metagenomics, Metadata and Meta-analysis” (M3) Special Interest Group (SIG) meeting held at the Intelligent Systems for Molecular Biology 2009 conference. The Genomic Standards Consortium (GSC) hosted this meeting to explore the bottlenecks and emerging solutions for obtaining biological insights through large-scale comparative analysis of metagenomic datasets. The M3 SIG included 16 talks, half of which were selected from submitted abstracts, a poster session and a panel discussion involving members of the GSC Board. This report summarizes this one-day SIG, attempts to identify shared themes and recapitulates community recommendations for the future of this field. The GSC will also host an M3 workshop at the Pacific Symposium on Biocomputing (PSB) in January 2010. Further information about the GSC and its range of activities can be found at http://gensc.org/. PMID:21304668

  17. Theoretical electronic structures and relative stabilities of the spinel oxynitrides M3NO3 (M=B,Al,Ga,In)

    NASA Astrophysics Data System (ADS)

    Okeke, Onyekwelu U.; Lowther, J. E.

    2008-03-01

    A spinel structure of an oxynitride material in the form M3NO3 ( M=B , Al, Ga, or In) is considered to be derived from a reaction of the form MN+M2O3→M3NO3 . Various possible phases of MN and M2O3 , which could lead to the M3NO3 spinel material, are considered. The spinels containing B and Al exhibit higher resistance to compression and shear than those containing Ga and In, and these are suggested to be potentially important hard materials possibly formed under extreme conditions. Calculated energetics of the proposed reaction favor the formation of spinels containing Ga and In with such materials having potentially significant optoelectronic applications.

  18. 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

  19. 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

  20. 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.

  1. 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.

  2. 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. PMID:23927230

  3. Solitary electrostatic waves are possible in unmagnetized symmetric pair plasmas

    SciTech Connect

    Dubinov, Alexander E.; Dubinova, Irina D.; Gordienko, Victor A.

    2006-08-15

    A possibility of stationary solitary electrostatic waves with large amplitude in symmetric unmagnetized symmetric pair plasmas (e{sup -}e{sup +} plasma, C{sub 60}{sup -}C{sub 60}{sup +} plasma or e{sup -}h{sup +} plasma) is proven. The main idea of the work is a thermodynamic unequilibrium of plasma species which may be created in low-density ideal pair plasmas. Ranges of parameters (Mach number M and a nonequilibrium degree {tau}=T{sub +}/T{sub -}) which lead to the possibility of solitary waves are found.

  4. SD-pair shell model study for {sup 126}Xe and {sup 128}Ba

    SciTech Connect

    Meng Xiangfei; Luo Yanan; Wang, Fu-rong; Pan Feng; Draayer, Jerry P.

    2008-04-15

    The SD-pair shell model is employed to study {sup 126}Xe and {sup 128}Ba. The results show that the spectra and electromagnetic transition strengths can be nicely described in terms of a three-parameter Hamiltonian. In our previous paper, we got a conclusion that the SD-pair approximation improves with the number of SD pairs N. This work shows that this conclusion can be extrapolated to the case with N=5.

  5. Pair interactions in red-faced warblers

    USGS Publications Warehouse

    Barber, P.M.; Martin, T.E.; Smith, Kimberly G.

    1998-01-01

    Forty pairs of breeding Red-faced Warblers (Cardellina rubrifrons) were observed in 1992 and 1993 on the Mogollon Rim, Arizona. Intrusions by extra-pair males, interactions between pair members, and other pair interaction behaviors were recorded. The majority of intrusions occurred during the building stage of the nesting cycle. Males responded to intrusions during nest building by decreasing intra-pair distance. Males maintained shorter intra-pair distances by following the female when she initiated movements and by not initiating pair movements themselves. Intra-pair distances were as short or shorter during the incubation period as during nest building, and were shorter during incubation than during egg laying. Males continued to follow females beyond the expected fertile period. Possible explanations for continued mate following include: males guard their mates against predators, males guard their paternity for future nesting attempts, and males respond to extra-pair male intrusions, which continue during incubation.

  6. Charge Aspects of Composite Pair Superconductivity

    NASA Astrophysics Data System (ADS)

    Flint, Rebecca

    2014-03-01

    Conventional Cooper pairs form from well-defined electronic quasiparticles, making the internal structure of the pair irrelevant. However, in the 115 family of superconductors, the heavy electrons are forming as they pair and the internal pair structure becomes as important as the pairing mechanism. Conventional spin fluctuation mediated pairing cannot capture the direct transition from incoherent local moments to heavy fermion superconductivity, but the formation of composite pairs favored by the two channel Kondo effect can. These composite pairs are local d-wave pairs formed by two conduction electrons in orthogonal Kondo channels screening the same local moment. Composite pairing shares the same symmetries as magnetically mediated pairing, however, only composite pairing necessarily involves a redistribution of charge within the unit cell originating from the internal pair structure, both as a monopole (valence change) and a quadrupole effect. This redistribution will onset sharply at the superconducting transition temperature. A smoking gun test for composite pairing is therefore a sharp signature at Tc - for example, a cusp in the Mossbauer isomer shift in NpPd5Al2 or in the NQR shift in (Ce,Pu)CoIn5.

  7. 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.

  8. Investigations on Sawtooth Reconnection in ASDEX Upgrade Tokamak Discharges Using the 3D Non-linear Two-fluid MHD Code M3D-C1

    NASA Astrophysics Data System (ADS)

    Krebs, Isabel; Jardin, Stephen C.; Igochine, Valentin; Guenter, Sibylle; Hoelzl, Matthias; ASDEX Upgrade Team

    2014-10-01

    We study sawtooth reconnection in ASDEX Upgrade tokamak plasmas by means of 3D non-linear two-fluid MHD simulations in toroidal geometry using the high-order finite element code M3D-C1. Parameters and equilibrium of the simulations are based on typical sawtoothing ASDEX Upgrade discharges. The simulation results are compared to features of the experimental observations such as the sawtooth crash time and frequency, the evolution of the safety factor profile and the 3D evolution of the temperature. 2D ECE imaging measurements during sawtooth crashes in ASDEX Upgrade indicate that the heat is transported out of the core through a narrow poloidally localized region. We investigate if incomplete sawtooth reconnection can be seen in the simulations which is suggested by soft X-ray tomography measurements in ASDEX Upgrade showing that an (m = 1, n = 1) perturbation is typically observed to survive the sawtooth crash and approximately maintain its radial position.

  9. 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.

  10. Kinetics of the vortex formation in the superconductors with d-pairing

    NASA Astrophysics Data System (ADS)

    Filippov, Alexander E.; Radievsky, Alexander V.; Zeltser, Alexander S.

    1996-03-01

    Heavy fermion systems and High- T c superconductors are related to the systems with d-pairing. We studied the kinetics of the vortex formation in the superconductors with d-pairing. New type of order parameter peculiarities and magnetic field maxima associated with them are found at intermediate stages of evolution from disordered to ordered state.

  11. Acetylcholine ameliorates endoplasmic reticulum stress in endothelial cells after hypoxia/reoxygenation via M3 AChR-AMPK signaling.

    PubMed

    Bi, Xueyuan; He, Xi; Xu, Man; Zhao, Ming; Yu, Xiaojiang; Lu, Xingzhu; Zang, Weijin

    2015-08-01

    Endoplasmic reticulum (ER) stress is associated with various cardiovascular diseases. However, its pathophysiological relevance and the underlying mechanisms in the context of hypoxia/reoxygenation (H/R) in endothelial cells are not fully understood. Previous findings have suggested that acetylcholine (ACh), the major vagal nerve neurotransmitter, protected against cardiomyocyte injury by activating AMP-activated protein kinase (AMPK). This study investigated the role of ER stress in endothelial cells during H/R and explored the beneficial effects of ACh. Our results showed that H/R triggered ER stress and apoptosis in endothelial cells, evidenced by the elevation of glucose-regulated protein 78, cleaved caspase-12 and C/EBP homologous protein expression. ACh significantly decreased ER stress and terminal deoxynucleotidyl transferase mediated dUTP-biotin nick end labeling positive cells and restored ER ultrastructural changes induced by H/R, possibly via protein kinase-like ER kinase and inositol-requiring kinase 1 pathways. Additionally, 4-diphenylacetoxy-N-methylpiperidine methiodide, a type-3 muscarinic ACh receptor (M3 AChR) inhibitor, abolished ACh-mediated increase in AMPK phosphorylation during H/R. Furthermore, M3 AChR or AMPK siRNA abrogated the ACh-elicited the attenuation of ER stress in endothelial cells, indicating that the salutary effects of ACh were likely mediated by M3 AChR-AMPK signaling. Overall, ACh activated AMPK through M3 AChR, thereby inhibited H/R-induced ER stress and apoptosis in endothelial cells. We have suggested for the first time that AMPK may function as an essential intermediate step between M3 AChR stimulation and inhibition of ER stress-associated apoptotic pathway during H/R, which may help to develop novel therapeutic approaches targeting ER stress to prevent or alleviate ischemia/reperfusion injury. PMID:26066647

  12. Acetylcholine ameliorates endoplasmic reticulum stress in endothelial cells after hypoxia/reoxygenation via M3 AChR-AMPK signaling

    PubMed Central

    Bi, Xueyuan; He, Xi; Xu, Man; Zhao, Ming; Yu, Xiaojiang; Lu, Xingzhu; Zang, Weijin

    2015-01-01

    Endoplasmic reticulum (ER) stress is associated with various cardiovascular diseases. However, its pathophysiological relevance and the underlying mechanisms in the context of hypoxia/reoxygenation (H/R) in endothelial cells are not fully understood. Previous findings have suggested that acetylcholine (ACh), the major vagal nerve neurotransmitter, protected against cardiomyocyte injury by activating AMP-activated protein kinase (AMPK). This study investigated the role of ER stress in endothelial cells during H/R and explored the beneficial effects of ACh. Our results showed that H/R triggered ER stress and apoptosis in endothelial cells, evidenced by the elevation of glucose-regulated protein 78, cleaved caspase-12 and C/EBP homologous protein expression. ACh significantly decreased ER stress and terminal deoxynucleotidyl transferase mediated dUTP-biotin nick end labeling positive cells and restored ER ultrastructural changes induced by H/R, possibly via protein kinase-like ER kinase and inositol-requiring kinase 1 pathways. Additionally, 4-diphenylacetoxy-N-methylpiperidine methiodide, a type-3 muscarinic ACh receptor (M3 AChR) inhibitor, abolished ACh-mediated increase in AMPK phosphorylation during H/R. Furthermore, M3 AChR or AMPK siRNA abrogated the ACh-elicited the attenuation of ER stress in endothelial cells, indicating that the salutary effects of ACh were likely mediated by M3 AChR-AMPK signaling. Overall, ACh activated AMPK through M3 AChR, thereby inhibited H/R-induced ER stress and apoptosis in endothelial cells. We have suggested for the first time that AMPK may function as an essential intermediate step between M3 AChR stimulation and inhibition of ER stress-associated apoptotic pathway during H/R, which may help to develop novel therapeutic approaches targeting ER stress to prevent or alleviate ischemia/reperfusion injury. PMID:26066647

  13. 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. PMID:10464008

  14. The power of paired genomes.

    PubMed

    Gerardo, Nicole M; Wilson, Alex C C

    2011-05-01

    Species interactions are fundamental to ecology. Classic studies of competition, predation, parasitism and mutualism between macroscopic organisms have provided a foundation for the discipline, but many of the most important and intimate ecological interactions are microscopic in scale. These microscopic interactions include those occurring between eukaryotic hosts and their microbial symbionts. Such symbioses, ubiquitous in nature, provide experimental challenges because the partners often cannot live outside the symbiosis. With respect to the symbionts, this precludes utilizing classical microbiological and genetic techniques that require in vitro cultivation. Genomics, however, has rapidly changed the study of symbioses. In this issue of Molecular Ecology, MacDonald et al. (2011), coupling symbiont whole-genome sequencing, experimental studies and metabolic modelling, provide novel insights into one of the best-studied symbioses, that between aphids and their obligate, nutrient-provisioning, intracellular bacteria, Buchnera aphidicola (Fig. 1). MacDonald and colleagues assessed variation in the ability of aphid–Buchnera pairs to thrive on artificial diets missing different amino acids. As shown previously (e.g. Wilkinson & Douglas 2003), aphid–Buchnera pairs can differ in their requirements for external sources of essential amino acids. Such phenotypic variation could result from differences in Buchnera’s amino acid biosynthetic capabilities or in the ability of aphids to interact with their symbionts. Whole-genome sequencing of the Buchnera genomes from four aphid lines with alternate nutritional phenotypes revealed that the environmental nutrients required by the aphid–Buchnera pairs could not be explained by sequence variation in the symbionts. Instead, a novel metabolic modelling approach suggested that much of the variation in nutritional phenotype could be explained by host variation in the capacity to provide necessary nutrient precursors to their

  15. 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.

  16. Topological superconductivity and unconventional pairing in oxide interfaces

    NASA Astrophysics Data System (ADS)

    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.

  17. Challenging preconceptions about Bell tests with photon pairs

    NASA Astrophysics Data System (ADS)

    Caprara Vivoli, V.; Sekatski, P.; Bancal, J.-D.; Lim, C. C. W.; Christensen, B. G.; Martin, A.; Thew, R. T.; Zbinden, H.; Gisin, N.; Sangouard, N.

    2015-01-01

    Motivated by very recent experiments, we consider a scenario "à la Bell" in which two protagonists test the Clauser-Horne-Shimony-Holt (CHSH) inequality using a photon-pair source based on spontaneous parametric down conversion and imperfect photon detectors. The conventional wisdom says that (i) if the detectors have unit efficiency, the CHSH violation can reach its maximum quantum value of 2 √{2 } . To obtain the maximal possible violation, it suffices that the source emits (ii) maximally entangled photon pairs (iii) in two well-defined single modes. Through a nonperturabive calculation of nonlocal correlations, we show that none of these statements are true. By providing the optimal pump parameters, measurement settings and state structure for any detection efficiency and dark count probability, our results give the recipe to close all the loopholes in a Bell test using photon pairs.

  18. 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

  19. Chaotic scattering of two identical point vortex pairs revisited

    NASA Astrophysics Data System (ADS)

    Tophøj, Laust; Aref, Hassan

    2008-09-01

    A new numerical exploration suggests that the motion of two vortex pairs, with constituent vortices all of the same absolute circulation, displays chaotic scattering regimes. The mechanisms leading to chaotic scattering are different from the "slingshot effect" identified by Price [Phys. Fluids A 5, 2479 (1993)] and occur in a different region of the four-vortex phase space. They may, in many cases, be understood by appealing to the solutions of the three-vortex problem obtained by merging two like-signed vortices into one of twice the strength and by assuming that the four-vortex problem has unstable periodic solutions similar to those seen in the thereby associated three-vortex problems. The integrals of motion, linear impulse and Hamiltonian are recast in a form appropriate for vortex pair scattering interactions that provides constraints on the parameters characterizing the outgoing vortex pairs in terms of the initial conditions.

  20. 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

  1. 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.

  2. Nanoscale Stabilization of New Phases in the PbTe-Sb2Te3 System: PbmSb2nTem+3n Nanocrystals

    SciTech Connect

    Soriano, Ronald B; Arachchige, Indika U; Malliakas, Christos D; Wu, Jinsong; Kanatzidis, Mercouri G

    2012-12-28

    A series of novel rock-salt-type PbmSb2nTem+3n nanocrystals (m = 2, 3, 4, 6, 8, and 10; n = 1 and 2) were successfully prepared using a colloidal synthesis route. These materials are stable only on the nanoscale and have no bulk analogues. Elemental compositions were determined using scanning transmission electron microscopy/energy-dispersive X-ray spectroscopy (STEM/EDS) and inductively coupled plasma atomic emission spectroscopy (ICP-AES). The nanocrystals exhibit well-defined band energies in the mid-IR region that are nearly independent of their atomic compositions. PbmSb2nTem+3n nanocrystals behave as metastable homogeneous solid solutions at room temperature and tend to phase separate into the respective binary PbTe + Sb2Te3 at 300 °C. Furthermore, pair distribution function (PDF) analysis suggests that the local structure of these PbmSb2nTem+3n nanocrystals is distorted with respect to the rock-salt structure.

  3. 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.

  4. 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

  5. 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.

  6. 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

  7. 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…

  8. 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…

  9. 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.

  10. Collective Modes and f-Wave Pairing Interactions in Superfluid {sup 3}He

    SciTech Connect

    Davis, J. P.; Choi, H.; Pollanen, J.; Halperin, W. P.

    2006-09-15

    Precision measurements of collective mode frequencies in superfluid {sup 3}He-B are sensitive to quasiparticle and f-wave pairing interactions. Measurements were performed at various pressures using interference of transverse sound in an acoustic cavity. We fit the measured collective mode frequencies, which depend on the strength of f-wave pairing and the Fermi liquid parameter F{sub 2}{sup s}, to theoretical predictions and discuss what implications these values have for observing new order parameter collective modes.

  11. The thermodynamics and kinetics of a nucleotide base pair.

    PubMed

    Wang, Yujie; Gong, Sha; Wang, Zhen; Zhang, Wenbing

    2016-03-21

    The thermodynamic and kinetic parameters of an RNA base pair were obtained through a long-time molecular dynamics simulation of the opening-closing switch process of the base pair near its melting temperature. The thermodynamic parameters were in good agreement with the nearest-neighbor model. The opening rates showed strong temperature dependence, however, the closing rates showed only weak temperature dependence. The transition path time was weakly temperature dependent and was insensitive to the energy barrier. The diffusion constant exhibited super-Arrhenius behavior. The free energy barrier of breaking a single base stack results from the enthalpy increase, ΔH, caused by the disruption of hydrogen bonding and base-stacking interactions. The free energy barrier of base pair closing comes from the unfavorable entropy loss, ΔS, caused by the restriction of torsional angles. These results suggest that a one-dimensional free energy surface is sufficient to accurately describe the dynamics of base pair opening and closing, and the dynamics are Brownian. PMID:27004898

  12. The thermodynamics and kinetics of a nucleotide base pair

    NASA Astrophysics Data System (ADS)

    Wang, Yujie; Gong, Sha; Wang, Zhen; Zhang, Wenbing

    2016-03-01

    The thermodynamic and kinetic parameters of an RNA base pair were obtained through a long-time molecular dynamics simulation of the opening-closing switch process of the base pair near its melting temperature. The thermodynamic parameters were in good agreement with the nearest-neighbor model. The opening rates showed strong temperature dependence, however, the closing rates showed only weak temperature dependence. The transition path time was weakly temperature dependent and was insensitive to the energy barrier. The diffusion constant exhibited super-Arrhenius behavior. The free energy barrier of breaking a single base stack results from the enthalpy increase, ΔH, caused by the disruption of hydrogen bonding and base-stacking interactions. The free energy barrier of base pair closing comes from the unfavorable entropy loss, ΔS, caused by the restriction of torsional angles. These results suggest that a one-dimensional free energy surface is sufficient to accurately describe the dynamics of base pair opening and closing, and the dynamics are Brownian.

  13. 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

  14. Meeting report: metagenomics, metadata and meta-analysis? (M3) Workshop at the Pacific Symposium on Biocomputing 2010.

    SciTech Connect

    Hirschman, L; Field, D; Wooley, J; Cochrane, G; Gilbert, J; Kolker, E; Kyrpides, N; Meyer, F; Mizrachi, I; Nakamura, Y; Sansone, S; Schriml, L; Tatusova, T; Owen, W; Yilmaz, P

    2010-01-01

    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.

  15. 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.

  16. Coherent Pair Production in Deformed Crystals with a Complex Base

    NASA Astrophysics Data System (ADS)

    Mkrtchyan, A. R.; Saharian, A. A.; Parazian, V. V.

    We investigate the coherent electron-positron pair creation by high-energy photons in a periodically deformed single crystal with a complex base. The formula for the corresponding differential cross-section is derived for an arbitrary deformation field. The conditions are specified under which the influence of the deformation is considerable. The case is considered in detail when the photon enters into the crystal at small angles with respect to a crystallographic axis. The results of the numerical calculations are presented for SiO2 single crystal and Moliere parametrization of the screened atomic potentials in the case of the deformation field generated by the acoustic wave of S type. In dependence of the parameters, the presence of deformation can either enhance or reduce the pair creation cross-section. This can be used to control the parameters of the positron sources for storage rings and colliders.

  17. 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.

  18. Paired States of Composite Fermions

    NASA Astrophysics Data System (ADS)

    Bonesteel, N. E.

    2002-03-01

    There is compelling theoretical evidence(R. Morf, Phys. Rev. Lett. 80), 1505 (1998). that the ν=5/2 fractional quantum Hall state is a Moore-Read state(G. Moore and N. Read, Nucl. Phys. B 360), 362 (1991). -- a state which can be viewed as a spin-polarized p-wave `superconductor' of composite fermions. The question remains, how can one test this hypothesis experimentally? To address this we have developed a semi-phenomenological description of this state in which the Halperin-Lee-Read(B.I. Halperin, P.A. Lee, and N. Read, Phys. Rev. B 47), 7312 (1993). theory of the half-filled Landau level is modified by adding a p-wave pairing interaction between composite fermions by hand. The electromagnetic response functions for the resulting mean-field superconducting state are then calculated and used in an RPA calculation of the physical electronic response. For a clean enough sample, and for q << k_f, the transverse electromagnetic response function for composite fermions is governed by type-II coherence factors and shows a `Hebel-Slichter'-like peak as a function of temperature for low enough frequency. The possibility (and potential difficulties) of observing this peak indirectly in surface-acoustic-wave propagation experiments will be discussed. The observation of such a coherence peak would provide strong evidence of BCS pairing in the 5/2 state. Work supported by US DOE Grant No. DE-FG02-97ER45639. Work done in collaboration with K.C. Foster (FSU) and S.H. Simon (Lucent). note

  19. 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

  20. M3 muscarinic receptors promote cell survival through activation of the extracellular regulated kinase (ERK1/2) pathway.

    PubMed

    Greenwood, Jeffrey M; Dragunow, Michael

    2010-08-25

    Activation of certain subtypes of the muscarinic acetylcholine receptor can enhance cell survival. In SK-N-SH human neuroblastoma cells, muscarinic acetylcholine receptor activation induces phosphorylation of CREB and induction of EGR1, transcription factors associated with cell growth and survival. We identified the M3 muscarinic acetylcholine receptor subtype as being primarily responsible for these transcription factor responses after stimulation with carbachol, using subtype-preferring receptor antagonists and muscarinic snake toxins. In a cell survival/death model in SK-N-SH cells deprived of serum growth factors, carbachol increased cell viability, an effect blocked by the non-specific muscarinic antagonist atropine and the M3-preferring antagonist 4-diphenylacetoxy-N-methylpiperidine methiodide (4-DAMP), suggesting that the M3 receptor is also driving the survival response in these cells. This cytoprotection is largely dependent on activation of the p44/42 extracellular regulated kinase (ERK1/2) pathway. Understanding such survival signalling pathways is important for both potential interventions in neurodegenerative disease and for targeting neuroblastoma and malignancies of the central nervous system. PMID:20519144

  1. Development of the My Medicines and Me (M3Q) side effect questionnaire for mental health patients: a qualitative study

    PubMed Central

    Ashoorian, Deena M.; Davidson, Rowan M.; Rock, Daniel J. T.; Seubert, Liza J.; Clifford, Rhonda M.

    2015-01-01

    Objective: The objective of this study was to assess the acceptability, content validity and usability of the My Medicines and Me (M3Q) self-report side effect questionnaire. Methods: Eight focus groups consisting of mental health patients, carers, general practitioners, psychiatrists, mental health nurses and pharmacists were conducted, involving 78 participants. Two researchers independently examined the transcriptions and analysed the data thematically using an inductive method. Results: The findings supported changes to the formatting, length and phrasing of questions in the original version of the questionnaire. Although the groups provided differing views on the usability of the M3Q in clinical practice, the patient and carer groups were unconditionally in favour of such a tool to be used systematically to describe patients’ subjective experiences with side effects. Conclusion: The differing contribution made by all groups involved in the administration and completion of the M3Q assisted with content validity of the questionnaire. The acceptability and usability of this novel side effect questionnaire was also explored, with many participants agreeing it was a necessary tool for a patient centred approach to treatment. Following implementation of the changes to the current format of the questionnaire, investigation into the uptake and use in clinical practice should be carried out. PMID:26557985

  2. Structure, stability, and dynamics of canonical and noncanonical base pairs: quantum chemical studies.

    PubMed

    Roy, Ashim; Panigrahi, Swati; Bhattacharyya, Malyasri; Bhattacharyya, Dhananjay

    2008-03-27

    The importance of non-Watson-Crick base pairs in the three-dimensional structure of RNA is now well established. The structure and stability of these noncanonical base pairs are, however, poorly understood. We have attempted to understand structural features of 33 frequently occurring base pairs using density functional theory. These are of three types, namely (i) those stabilized by two or more polar hydrogen bonds between the bases, (ii) those having one polar and another C-H...O/N type interactions, and (iii) those having one H-bond between the bases and another involving one of the sugars linked to the bases. We found that the base pairs having two polar H-bonds are very stable as compared to those having one C-H...O/N interaction. Our quantitatively analysis of structures of these optimized base pairs indicates that they possess a different amount of nonplanarity with large propeller or buckle values as also observed in the crystal structures. We further found that geometry optimization does not modify the hydrogen-bonding pattern, as values of shear and open angle of the base pairs remain conserved. The structures of initial crystal geometry and final optimized geometry of some base pairs having only one polar H-bond and a C-H...O/N interaction, however, are significantly different, indicating the weak nature of the nonpolar interaction. The base pair flexibility, as measured from normal-mode analysis, in terms of the intrinsic standard deviations of the base pair structural parameters are in conformity with those calculated from RNA crystal structures. We also noticed that deformation of a base pair along the stretch direction is impossible for all of the base pairs, and movements of the base pairs along shear and open are also quite restricted. The base pair opening mode through alteration of propeller or buckle is considerably less restricted for most of the base pairs. PMID:18318519

  3. Inconsistencies in the description of pairing effects in nuclear level densities

    NASA Astrophysics Data System (ADS)

    Schmidt, Karl-Heinz; Jurado, Beatriz

    2012-10-01

    Pairing correlations have a strong influence on nuclear level densities. Empirical descriptions and theoretical models have been developed to take these effects into account. The present article discusses cases, where descriptions of nuclear level densities are inconsistent or in conflict with the present understanding of nuclear properties. Phenomenological approaches consider an energy-shift parameter. However, the absolute magnitude of the energy shift, which actually corresponds to the pairing condensation energy, is generally not compatible with the observation that stable pairing correlations are present in essentially all nuclei. It is also shown that in the BCS model pairing condensation energies and critical pairing energies are inconsistent for light nuclei. A modification to the composite Gilbert-Cameron level-density description is proposed, and the use of more realistic pairing theories is suggested.

  4. 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

  5. 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

  6. Galaxy pairs align with Galactic filaments

    NASA Astrophysics Data System (ADS)

    Tempel, E.; Tamm, A.

    2015-04-01

    Context. Gravitational collapse theory and numerical simulations suggest that the velocity field within large-scale galaxy filaments is dominated by motions along the filaments. Aims: Our aim is to check whether observational data reveal any preferred orientation of galaxy pairs with respect to the underlying filaments as a result of the expectedly anisotropic velocity field. Methods: We use galaxy pairs and galaxy filaments identified from Sloan Digital Sky Survey data. For filament extraction, we use the Bisous model that is based on the marked point process technique. During the filament detection, we use the centre point of each pair instead of the positions of galaxies to avoid a built-in influence of pair orientation on the filament construction. For pairs lying within filaments (3012 cases), we calculate the angle between the line connecting the galaxies of each pair and their host filaments. To avoid redshift-space distortions, the angle is measured in the plane of the sky. Results: The alignment analysis shows that the orientation of galaxy pairs correlates strongly with their host filaments. The alignment signal is stronger for loose pairs, with at least 25% excess of aligned pairs compared to a random distribution. The alignment of galaxy pairs and filaments measured from the observational data is in good agreement with the alignment in the Millennium simulation and thus provides support to the ΛCDM formalism.

  7. 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.

  8. 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.

  9. 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

  10. 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

  11. 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.

  12. 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

  13. 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.

  14. Development of a 5,000 m(3) super-pressure balloon with a diamond-shaped net

    NASA Astrophysics Data System (ADS)

    Saito, Yoshitaka; Tanaka, Shigeki; Nakashino, Kyoichi; Matsushima, Kiyoho; Goto, Ken; Furuta, Ryosuke; Domoto, Kodai; Akita, Daisuke; Hashimoto, Hiroyuki

    A light super-pressure balloon of which weight will be comparable to the weight of the zero-pressure balloon has been developed using a method to cover a balloon with a diamond-shaped net of high-tensile fibers. The goal is to fly a payload of 900 kg to the altitude of 37 km with a 300,000 m(3) balloon. A flight test of a 3,000 m(3) balloon in the tandem balloon configuration with a 15,000 m(3) zero-pressure balloon was performed in 2012. Although a small gas leak occurred in the super-pressure balloon at the differential pressure of 400 to 500 Pa, the differential pressure reached the highest value of 814 Pa and kept positive through the level flight lasting for 25 minutes due to its slow leakage. To avoid a possible stress concentration to films at the polar area, a new design setting the meridian length of the balloon gore film equal to the length of the net was adopted. A 3-m balloon with the design was developed and its capacity to resist pressure at room temperature and at -30 (°) C was checked through the ground inflation tests. In 2013, a balloon of the same model was launched in the tandem balloon configuration with 2 kg rubber balloons. It was confirmed that the balloon could withstand the maximum differential pressure of 6,280 Pa, could withstand the differential pressure of 5,600 Pa for 2 hours, and there was a small gas leak through a hole with an area of 0.4 mm(2) which was also found in the ground leakage test. These results indicated that the improvement was adequate and there was no problem for the super-pressure balloon to fly in the environment of the stratosphere except for the problem of the small gas leak. In 2014, a flight test of a 5,000 m(3) balloon will be performed. In this paper, after reviewing the method to cover a balloon with a diamond-shaped net, the current status of the development will be reported.

  15. 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

  16. 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

  17. 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

  18. Analytical expressions for group-delay dispersion and third-order dispersion of a reflection grism-pair compressor.

    PubMed

    Su, Juan; Feng, Guoying

    2012-05-10

    We provide a detailed analytical expression of group-delay dispersion (GDD) and third-order dispersion (TOD) for a reflection grism-pair compressor without the first-order approximation of grating diffraction. The analytical expressions can be used to design a grism-pair compressor for compensating the dispersive material without ray tracing. Furthermore, the dispersion performance of the grism pair compressor, depending on compressor parameters, is comprehensively analyzed. Results are shown that we can adjust several parameters to obtain a certain GDD and TOD, such as the incidence angle of the beam, refractive index of the prism, grating constant, and the separation of the grism pair. PMID:22614499

  19. 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

  20. 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.

  1. 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.

  2. Electromagnetic lepton-pair production in relativistic collisions

    NASA Astrophysics Data System (ADS)

    Albert, C. J.; Ernst, D. J.; Strayer, M. R.; Bottcher, C.

    Electromagnetic lepton-pair production in relativistic collisions is studied in an ab initio approach with no free parameters. After a semi-classical approximation to the relative motion of the two incident particles is made, the resulting second-order diagram is calculated using a Monte Carlo technique to evaluate the resulting seven-dimensional integral. We examine the case of electron-positron pair production in pi(-)p collisions at p(sub pi) = 17 GeV. We find that a significant fraction of the measured pairs in this reaction are produced via the magnetic spin-flip current of the proton. Approaches, such as the equivalent photon approximation, which neglect this part of the current predict much too small a cross section. This feature is traced to the cuts imposed in taking the experimental data. Lepton-pair production in the scattering of He-3, He-4 and He-4, He-4 is proposed as a clean way of experimentally separating the spin-flip and non-flip processes; predictions are made for these systems.

  3. 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

  4. Effects of disorder and motion in a radical pair magnetoreceptor

    PubMed Central

    Lau, Jason C. S.; Wagner-Rundell, Nicola; Rodgers, Christopher T.; Green, Nicholas J. B.; Hore, P. J.

    2010-01-01

    A critical requirement in the proposed chemical model of the avian magnetic compass is that the molecules that play host to the magnetically sensitive radical pair intermediates must be immobilized and rotationally ordered within receptor cells. Rotational disorder would cause the anisotropic responses of differently oriented radical pairs within the same cell to interfere destructively, while rapid molecular rotation would tend to average the crucial anisotropic magnetic interactions and induce electron spin relaxation, reducing the sensitivity to the direction of the geomagnetic field. So far, experimental studies have been able to shed little light on the required degree of ordering and immobilization. To address this question, computer simulations have been performed on a collection of radical pairs undergoing restricted rigid-body rotation, coherent anisotropic spin evolution, electron spin relaxation and spin-selective recombination reactions. It is shown that the ordering and motional constraints necessary for efficient magnetoreception can be simultaneously satisfied if the radical pairs are uniaxially ordered with a moderate order parameter and if their motional correlation time is longer than about a quarter of their lifetime. PMID:20007172

  5. 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

  6. 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.

  7. Functional muscarinic M2 and M3 receptors and beta-adrenoceptor in cultured rat bladder smooth muscle.

    PubMed

    Ma, Fu Hai; Higashira-Hoshi, Hanae; Itoh, Yoshinori

    2002-01-25

    A highly purified rat urinary bladder smooth muscle cell culture was obtained by a modified enzymic isolation method, and the presence of functional muscarinic as well as beta-adrenergic receptors were subsequently determined. At 7-10 days of culture, cells became elongated and spindle-shaped showing a typical "hills and valleys" form. They were stained with anti-alpha-actin and anti-myosin antibodies. Radiolabeled ligand binding using [3H]N-methylscopolamine and [3H]CGP12177 showed that these cells expressed muscarinic and beta-adrenergic receptors. Stimulation of cultured cells with carbachol inhibited the forskolin-stimulated cyclic AMP formation, caused an elevation of intracellular Ca2+ concentration measured by fura-2 fluorometry. The latter response was almost completely blocked by 4-DAMP, a selective muscarinic M3 antagonist. On the other hand, stimulation of cultured cells with isoproterenol enhanced the basal cyclic AMP formation, which was reversed by carbachol. Therefore, the presence of functional muscarinic (both M2 and M3) as well as beta-adrenergic receptors was confirmed in pure culture of the rat bladder smooth muscle cells obtained by using an enzymic isolation method. PMID:11848300

  8. Isolated galaxies, pairs, and groups of galaxies

    NASA Technical Reports Server (NTRS)

    Kuneva, I.; Kalinkov, M.

    1990-01-01

    The authors searched for isolated galaxies, pairs and groups of galaxies in the CfA survey (Huchra et al. 1983). It was assumed that the distances to galaxies are given by R = V/H sub o, where H sub o = 100 km s(exp -1) Mpc(exp -1) and R greater than 6 Mpc. The searching procedure is close to those, applied to find superclusters of galaxies (Kalinkov and Kuneva 1985, 1986). A sphere with fixed radius r (asterisk) is described around each galaxy. The mean spatial density in the sphere is m. Let G (sup 1) be any galaxy and G (sup 2) be its nearest neighbor at a distance R sub 2. If R sub 2 exceeds the 95 percent quintile in the distribution of the distances of the second neighbors, then G (sup 1) is an isolated galaxy. Let the midpoint of G (sup 1) and G (sup 2) be O sub 2 and r sub 2=R sub 2/2. For the volume V sub 2, defined with the radius r sub 2, the density D sub 2 less than k mu, the galaxy G (sup 2) is a single one and the procedure for searching for pairs and groups, beginning with this object is over and we have to pass to another object. Here the authors present the groups - isolated and nonisolated - with n greater than 3, found in the CfA survey in the Northern galactic hemisphere. The parameters used are k = 10 and r (asterisk) = 5 Mpc. Table 1 contains: (1) the group number, (2) the galaxy, nearest to the multiplet center, (3) multiplicity n, (4) the brightest galaxy if it is not listed in (2); (5) and (6) are R.A. and Dec. (1950), (7) - mean distance D in Mpc. Further there are the mean density rho (8) of the multiplet (galaxies Mpc (exp -3), (9) the density rho (asterisk) for r (asterisk) = 5 Mpc and (10) the density rho sub g for the group with its nearest neighbor. The parenthesized digits for densities in the last three columns are powers of ten.

  9. Pair breaking and ``intrinsic`` {Tc}

    SciTech Connect

    Wolf, S.A.; Kresin, V.Z.; Ovchinnikov, Y.N.

    1996-12-31

    An analysis of the temperature dependence of the upper critical field in several cuprate families leads to the conclusion that magnetic impurities are present even in samples with the maximum observed value of T{sub c}. A new parameter, intrinsic T{sub c} (T{sub c;intr}) which is its value in the absence of magnetic impurities, is introduced. The maximum value of T{sub c;intr}, which corresponds to the maximum doping level, appears to be similar for different cuprates and to be equal to 160--170 K. This is an upper limit of T{sub c} in the cuprates.

  10. 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…

  11. Widnall instabilities in vortex pairs

    NASA Astrophysics Data System (ADS)

    Sipp, Denis; Jacquin, Laurent

    2003-07-01

    In this article we analyze the cooperative three-dimensional short-wave instabilities developing on concentrated vortex dipoles that have been obtained by means of two-dimensional direct numerical simulations. These dipoles are characterized by their aspect ratio a/b where a is the radius of the vortices based on the polar moments of vorticity and b is the separation between the vortex centroids. In the inviscid case, we show that the selection of the antisymmetric eigenmode smoothly increases with a/b: for a/b=0.208, the amplification rate of the antisymmetric eigenmode is only 1.4% larger than the amplification rate of the symmetric eigenmode. When a/b=0.288, this difference increases up to 7%. The results of the normal mode analysis may be compared to those of an asymptotic stability analysis of a Lamb-Oseen vortex subjected to a weak straining field, following Moore and Saffman [Proc. R. Soc. London, Ser. A 346, 413 (1975)]. This theory shows that the instability may occur whenever two Kelvin waves exist with the same frequency ω, the same axial wavenumber k and with azimuthal wavenumbers m and m+2. Contrary to the case of a Rankine vortex [Tsai and Widnall, J. Fluid Mech. 73, 721 (1976)], the presence of critical layers in a Lamb-Oseen vortex prevents a large number of possible resonances. For example, resonances between m=-2 and m=0 modes lead to damped modes. The only resonances that occur are related to the stationary (ω=0) bending waves (m=±1) obtained for specific values of the axial wavenumber. All these predictions are found to be in good agreement with the results obtained by the stability analysis of the considered vortex pairs. At last, we present a nonautonomous amplitude equation which takes into account all effects of viscosity, i.e., the viscous damping of the amplification rate of the perturbation but also the increase of the dipole aspect ratio a/b due to the viscous diffusion of the basic flowfield. The low-Reynolds number experiment of

  12. 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.

  13. 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…

  14. Paired Placements for Early Field Experiences

    ERIC Educational Resources Information Center

    Cohen, Myrna D.; Nath, Janice L.

    2006-01-01

    This article describes and evaluates the pairing of 2 preservice teachers to 1 mentor for early fieldwork. Traditionally, many programs have been reluctant to assign more than 1 student to a mentor. This study describes how the pairing is implemented; it addresses practical considerations; and it evaluates the innovation. Feedback gathered from…

  15. 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.

  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. Fundamental pairs in nuclear collective motion

    NASA Astrophysics Data System (ADS)

    Naotaka, Yoshinaga

    1994-03-01

    Usefulness of the pair approximation is shown in both vibrational and rotational regions. The renormalized SDG-pair space is sufficiently enough to reproduce moment of inertia of the ground band that was previously thought as a difficult physical quantity to be reproduced.

  18. Paired Reading Bulletin. Spring 1988, No. 4.

    ERIC Educational Resources Information Center

    Paired Reading Bulletin, 1988

    1988-01-01

    The annual bulletin of the Paired Reading Project contains 17 feature articles: (1) "Parental Involvement in Reading and Language" (F. Burton); (2) "Infant/Infant Cross-Age Peer Group Tuition" (A. Low and M.Davies); (3) "Comment on Low & Davies" (K. Topping); (4) "Paired Reading in Reaside Middle School" (F. Gautrey); (5) "Sex Differences in the…

  19. 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

  20. 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.

  1. 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.

  2. Pairing effect and misleading regularity

    NASA Astrophysics Data System (ADS)

    Al-Sayed, A.

    2015-11-01

    We study the nearest neighbor spacing distribution of energy levels of even-even nuclei classified according to their reduced electric quadrupole transition probability B (E2) ↑ using the available experimental data. We compare between Brody, and Abul-Magd distributions that extract the degree of chaoticity within nuclear dynamics. The results show that Abul-Magd parameter f can represents the chaotic behavior in more acceptable way than Brody, especially if a statistically significant study is desired. A smooth transition from chaos to order is observed as B (E2) ↑ increases. An apparent regularity was located at the second interval, namely: at 0.05 ≤ B (E2) < 0.1 in e2b2 units, and at 10 ≤ B (E2) < 15 in Weisskopf unit. Finally, the chaotic behavior parameterized in terms of B (E2) ↑ does not depend on the unit used.

  3. Pair tunneling of bosonic atoms in an optical lattice

    SciTech Connect

    Zhou Xiangfa; Zhang Yongsheng; Guo Guangcan

    2009-07-15

    We show that atom-molecule coupling with large detuning can cause effective hopping of pairs of bosonic atoms in a state-dependent optical lattice. Taking advantage of the high controllability of all relevant parameters in such systems, we discuss the pair-superfluid (PSF) to Mott insulator (MI) transition using the effective model within mean-field theory. In the presence of on-site disorder, simultaneous tunneling of bosonic atoms can result in a compressible weak Mott insulating phase. We have also investigated the coexistence of superfluid (SF) and PSF in the lattice, and found that the competition between the two hopping mechanisms can cause a first-order PSF(SF)-MI transition.

  4. 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.

  5. Pair correlations in classical crystals: The shortest-graph method

    NASA Astrophysics Data System (ADS)

    Yurchenko, Stanislav O.; Kryuchkov, Nikita P.; Ivlev, Alexei V.

    2015-07-01

    The shortest-graph method is applied to calculate the pair correlation functions of crystals. The method is based on the representation of individual correlation peaks by the Gaussian functions, summed along the shortest graph connecting the two given points. The analytical expressions for the Gaussian parameters are derived for two- and three-dimensional crystals. The obtained results are compared with the pair correlation functions deduced from the molecular dynamics simulations of Yukawa, inverse-power law, Weeks-Chandler-Andersen, and Lennard-Jones crystals. By calculating the Helmholtz free energy, it is shown that the method is particularly accurate for soft interparticle interactions and for low temperatures, i.e., when the anharmonicity effects are insignificant. The accuracy of the method is further demonstrated by deriving the solid-solid transition line for Yukawa crystals, and the compressibility for inverse-power law crystals.

  6. 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.

  7. Independent pair parton interactions model of hadron interactions

    NASA Astrophysics Data System (ADS)

    Dremin, I. M.; Nechitailo, V. A.

    2004-08-01

    A model of independent pair parton interactions is proposed, according to which hadron interactions are represented by a set of independent binary parton collisions. The final multiplicity distribution is described by a convolution of the negative binomial distributions in each of the partonic collisions. As a result, it is given by a weighted sum of negative binomial distributions with parameters multiplied by the number of active pairs. Its shape and moments are considered. Experimental data on multiplicity distributions in high energy pp¯ processes are well fitted by these distributions. Predictions for the CERN Large Hadron Collider and higher energies are presented. The difference between e+e- and pp¯ processes is discussed.

  8. Supersymmetric Higgs boson pair production at hadron colliders

    SciTech Connect

    Belyaev, A.; Drees, M.; Eboli, O.J.; Novaes, S.F.; Belyaev, A.; Mizukoshi, J.K.

    1999-10-01

    We study the pair production of neutral Higgs bosons through gluon fusion at hadron colliders in the framework of the minimal supersymmetric standard model. We present analytical expressions for the relevant amplitudes, including both quark and squark loop contributions, and allowing for mixing between the superpartners of left- and right-handed quarks. Squark loop contributions can increase the cross section for the production of two CP-even Higgs bosons by more than two orders of magnitude, if the relevant trilinear soft breaking parameter is large and the mass of the lighter squark eigenstate is not too far above its current lower bound. In the region of large tan&hthinsp;{beta}, neutral Higgs boson pair production might even be observable in the 4b final state during the next run of the Fermilab Tevatron collider. {copyright} {ital 1999} {ital The American Physical Society}

  9. 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

  10. 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.

  11. 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.

  12. 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.

  13. Geometric nomenclature and classification of RNA base pairs.

    PubMed Central

    Leontis, N B; Westhof, E

    2001-01-01

    Non-Watson-Crick base pairs mediate specific interactions responsible for RNA-RNA self-assembly and RNA-protein recognition. An unambiguous and descriptive nomenclature with well-defined and nonoverlapping parameters is needed to communicate concisely structural information about RNA base pairs. The definitions should reflect underlying molecular structures and interactions and, thus, facilitate automated annotation, classification, and comparison of new RNA structures. We propose a classification based on the observation that the planar edge-to-edge, hydrogen-bonding interactions between RNA bases involve one of three distinct edges: the Watson-Crick edge, the Hoogsteen edge, and the Sugar edge (which includes the 2'-OH and which has also been referred to as the Shallow-groove edge). Bases can interact in either of two orientations with respect to the glycosidic bonds, cis or trans relative to the hydrogen bonds. This gives rise to 12 basic geometric types with at least two H bonds connecting the bases. For each geometric type, the relative orientations of the strands can be easily deduced. High-resolution examples of 11 of the 12 geometries are presently available. Bifurcated pairs, in which a single exocyclic carbonyl or amino group of one base directly contacts the edge of a second base, and water-inserted pairs, in which single functional groups on each base interact directly, are intermediate between two of the standard geometries. The nomenclature facilitates the recognition of isosteric relationships among base pairs within each geometry, and thus facilitates the recognition of recurrent three-dimensional motifs from comparison of homologous sequences. Graphical conventions are proposed for displaying non-Watson-Crick interactions on a secondary structure diagram. The utility of the classification in homology modeling of RNA tertiary motifs is illustrated. PMID:11345429

  14. 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.

  15. Cryptolepis sanguinolenta: antimuscarinic properties of cryptolepine and the alkaloid fraction at M1, M2 and M3 receptors.

    PubMed

    Rauwald, H W; Kober, M; Mutschler, E; Lambrecht, G

    1992-12-01

    From an ethanol extract of the roots of Cryptolepis sanguinolenia the alkaloid fraction and its main constituent cryptolepine were isolated by partitioning at pH 11 and column chromatography using silica gel and chloroform/methanol as eluent. Cryptolepine was identified mainly by EI-MS and 1H/13C-NMR spectroscopy. Cryptolepine (3-30 microM) and the alkaloid fraction of Cryptolepis sanguinolenta (3-10 micrograms/ml) antagonized muscarinic effects at M1 receptors in rabbit vas deferens, M2 receptors in guinea-pig atria, and M3 receptors in guinea-pig ileum. The experiments, using N-methylatropine as reference drug, showed a significant antimuscarinic activity for both cryptolepine and the alkaloid fraction, but no appreciable receptor subtype selectivity (pA2 = 5.00-5.73). Cryptolepine was determined as the antimuscarinic principle of Cryptolepis sanguinolenta. At higher concentrations both materials displayed negative inotropic effects. PMID:1484884

  16. 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.

  17. 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

  18. 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

  19. GPX3 hypermethylation serves as an independent prognostic biomarker in non-M3 acute myeloid leukemia

    PubMed Central

    Zhou, Jing-Dong; Yao, Dong-Ming; Zhang, Ying-Ying; Ma, Ji-Chun; Wen, Xiang-Mei; Yang, Jing; Guo, Hong; Chen, Qin; Lin, Jiang; Qian, Jun

    2015-01-01

    Hypermethylation of GPX3 (glutathione peroxidase 3) promoter has been identified in various solid tumors. However, the pattern of GPX3 promoter methylation in acute myeloid leukemia (AML) remains unknown. The current study was intended to investigate the clinical significance of GPX3 promoter methylation in de novo AML patients and further determine its role in regulating GPX3 expression. GPX3 promoter methylation status was detected in 181 de novo AML patients and 44 normal controls by real-time quantitative methylation-specific PCR and bisulfite sequencing PCR. Real-time quantitative PCR was carried out to assess GPX3 expression. GPX3 promoter was significantly methylated in AML patients compared with normal controls (P=0.022). The patients with GPX3 methylation presented significantly older age than those with GPX3 unmethylation (P=0.011). GPX3 methylated patients had significantly lower frequency of C/EBPA mutation and higher incidence of FLT3-ITD mutation (P=0.037 and 0.030, respectively). The non-M3 patients with GPX3 methylation had significantly lower overall survival than those with GPX3 unmethylation (P=0.036). No significant correlation was observed between GPX3 expression and its promoter methylation (R=0.110, P=0.284). However, GPX3 mRNA level was significantly increased after 5-aza-2’-deoxycytidine treatment in leukemic cell line THP1. Our data suggest that GPX3 methylation predicts adverse clinical outcome in non-M3 AML patients. Moreover, GPX3 expression is regulated by its promoter methylation in leukemic cell line THP1. PMID:26269763

  20. GPX3 hypermethylation serves as an independent prognostic biomarker in non-M3 acute myeloid leukemia.

    PubMed

    Zhou, Jing-Dong; Yao, Dong-Ming; Zhang, Ying-Ying; Ma, Ji-Chun; Wen, Xiang-Mei; Yang, Jing; Guo, Hong; Chen, Qin; Lin, Jiang; Qian, Jun

    2015-01-01

    Hypermethylation of GPX3 (glutathione peroxidase 3) promoter has been identified in various solid tumors. However, the pattern of GPX3 promoter methylation in acute myeloid leukemia (AML) remains unknown. The current study was intended to investigate the clinical significance of GPX3 promoter methylation in de novo AML patients and further determine its role in regulating GPX3 expression. GPX3 promoter methylation status was detected in 181 de novo AML patients and 44 normal controls by real-time quantitative methylation-specific PCR and bisulfite sequencing PCR. Real-time quantitative PCR was carried out to assess GPX3 expression. GPX3 promoter was significantly methylated in AML patients compared with normal controls (P=0.022). The patients with GPX3 methylation presented significantly older age than those with GPX3 unmethylation (P=0.011). GPX3 methylated patients had significantly lower frequency of C/EBPA mutation and higher incidence of FLT3-ITD mutation (P=0.037 and 0.030, respectively). The non-M3 patients with GPX3 methylation had significantly lower overall survival than those with GPX3 unmethylation (P=0.036). No significant correlation was observed between GPX3 expression and its promoter methylation (R=0.110, P=0.284). However, GPX3 mRNA level was significantly increased after 5-aza-2'-deoxycytidine treatment in leukemic cell line THP1. Our data suggest that GPX3 methylation predicts adverse clinical outcome in non-M3 AML patients. Moreover, GPX3 expression is regulated by its promoter methylation in leukemic cell line THP1. PMID:26269763

  1. GPX3 hypermethylation serves as an independent prognostic biomarker in non-M3 acute myeloid leukemia.

    PubMed

    Zhou, Jing-Dong; Yao, Dong-Ming; Zhang, Ying-Ying; Ma, Ji-Chun; Wen, Xiang-Mei; Yang, Jing; Guo, Hong; Chen, Qin; Lin, Jiang; Qian, Jun

    2015-01-01

    Hypermethylation of GPX3 (glutathione peroxidase 3) promoter has been identified in various solid tumors. However, the pattern of GPX3 promoter methylation in acute myeloid leukemia (AML) remains poorly known. The current study was intended to investigate the clinical significance of GPX3 promoter methylation in de novo AML patients and further determine its role in regulating GPX3 expression. GPX3 promoter methylation status in 181 de novo AML patients and 44 normal controls was detected by real-time quantitative methylation-specific PCR and bisulfite sequencing PCR. Real-time quantitative PCR was carried out to assess GPX3 expression. GPX3 promoter was significantly methylated in 181 AML patients compared with normal controls (P=0.022). The patients with GPX3 methylation presented significantly older age than those with GPX3 unmethylation (P=0.011). GPX3 methylated patients had significantly lower frequency of C/EBPA mutation and higher incidence of FLT3-ITD mutation (P=0.037 and 0.030). The non-M3 patients with GPX3 methylation had significantly lower overall survival than thoes with GPX3 unmethylation (P=0.036). No significant correlation was observed between GPX3 expression and its promoter methylation (R=0.110, P=0.284). However, GPX3 mRNA level was significantly increased after 5-aza-2'-deoxycytidine treatment in leukemic cell line THP1. GPX3 methylation predicts adverse clinical outcome in non-M3 AML patients. Moreover, GPX3 expression is regulated by its promoter methylation in leukemic cell line THP1. PMID:26175946

  2. GPX3 hypermethylation serves as an independent prognostic biomarker in non-M3 acute myeloid leukemia

    PubMed Central

    Zhou, Jing-Dong; Yao, Dong-Ming; Zhang, Ying-Ying; Ma, Ji-Chun; Wen, Xiang-Mei; Yang, Jing; Guo, Hong; Chen, Qin; Lin, Jiang; Qian, Jun

    2015-01-01

    Hypermethylation of GPX3 (glutathione peroxidase 3) promoter has been identified in various solid tumors. However, the pattern of GPX3 promoter methylation in acute myeloid leukemia (AML) remains poorly known. The current study was intended to investigate the clinical significance of GPX3 promoter methylation in de novo AML patients and further determine its role in regulating GPX3 expression. GPX3 promoter methylation status in 181 de novo AML patients and 44 normal controls was detected by real-time quantitative methylation-specific PCR and bisulfite sequencing PCR. Real-time quantitative PCR was carried out to assess GPX3 expression. GPX3 promoter was significantly methylated in 181 AML patients compared with normal controls (P=0.022). The patients with GPX3 methylation presented significantly older age than those with GPX3 unmethylation (P=0.011). GPX3 methylated patients had significantly lower frequency of C/EBPA mutation and higher incidence of FLT3-ITD mutation (P=0.037 and 0.030). The non-M3 patients with GPX3 methylation had significantly lower overall survival than thoes with GPX3 unmethylation (P=0.036). No significant correlation was observed between GPX3 expression and its promoter methylation (R=0.110, P=0.284). However, GPX3 mRNA level was significantly increased after 5-aza-2’-deoxycytidine treatment in leukemic cell line THP1. GPX3 methylation predicts adverse clinical outcome in non-M3 AML patients. Moreover, GPX3 expression is regulated by its promoter methylation in leukemic cell line THP1. PMID:26175946

  3. 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

  4. Bound free electron-positron pair production accompanied by giant dipole resonances

    SciTech Connect

    Senguel, M. Y.; Gueclue, M. C.

    2011-01-15

    At the Relativistic Heavy Ion Collider (RHIC) and the Large Hadron Collider (LHC), for example, virtual photons produce many particles. At small impact parameters where the colliding nuclei make peripheral collisions, photon fluxes are very large and these are responsible for the multiple photonuclear interactions. Free pair productions, bound free pair productions, and nuclear Coulomb excitations are important examples of such interactions, and these processes play important roles in the beam luminosity at RHIC and LHC. Here we obtained the impact parameter dependence of bound free pair production cross sections and by using this probability we obtained bound free electron-positron pair production with nuclear breakup for heavy ion collisions at RHIC and LHC. We also compared our results to the other calculations.

  5. 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

  6. 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.

  7. 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.

  8. Effects of triaxial deformation and pairing correlation on the proton emitter {sup 145}Tm

    SciTech Connect

    Yao, J. M.; Sun, B.; Woods, P. J.; Meng, J.

    2008-02-15

    The ground-state properties of the recent reported proton emitter {sup 145}Tm have been studied within the axially or triaxially deformed relativistic mean field (RMF) approaches, in which the pairing correlation is taken into account by the BCS-method with a constant pairing gap. It is found that triaxiality and pairing correlations play important roles in reproducing the experimental one proton separation energy. The single-particle level, the proton emission orbit, the deformation parameters {beta}=0.22 and {gamma}=28.98 deg. and the corresponding spectroscopic factor for {sup 145}Tm in the triaxial RMF calculation are given as well.

  9. 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

  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. Pair creation in heavy ion channeling

    NASA Astrophysics Data System (ADS)

    Belov, N. A.; Harman, Z.

    2016-04-01

    Heavy ions channeled through crystals with multi-GeV kinetic energies can create electron-positron pairs. In the framework of the ion, the energy of virtual photons arising from the periodic crystal potential may exceed the threshold 2mec2. The repeated periodic collisions with the crystal ions yield high pair production rates. When the virtual photon frequency matches a nuclear transition in the ion, the production rate can be resonantly increased. In this two-step excitation-pair conversion scheme, the excitation rates are coherently enhanced, and scale approximately quadratically with the number of crystal sites along the channel.

  12. Efficient and accurate local approximations to coupled-electron pair approaches: An attempt to revive the pair natural orbital method

    NASA Astrophysics Data System (ADS)

    Neese, Frank; Wennmohs, Frank; Hansen, Andreas

    2009-03-01

    Coupled-electron pair approximations (CEPAs) and coupled-pair functionals (CPFs) have been popular in the 1970s and 1980s and have yielded excellent results for small molecules. Recently, interest in CEPA and CPF methods has been renewed. It has been shown that these methods lead to competitive thermochemical, kinetic, and structural predictions. They greatly surpass second order Møller-Plesset and popular density functional theory based approaches in accuracy and are intermediate in quality between CCSD and CCSD(T) in extended benchmark studies. In this work an efficient production level implementation of the closed shell CEPA and CPF methods is reported that can be applied to medium sized molecules in the range of 50-100 atoms and up to about 2000 basis functions. The internal space is spanned by localized internal orbitals. The external space is greatly compressed through the method of pair natural orbitals (PNOs) that was also introduced by the pioneers of the CEPA approaches. Our implementation also makes extended use of density fitting (or resolution of the identity) techniques in order to speed up the laborious integral transformations. The method is called local pair natural orbital CEPA (LPNO-CEPA) (LPNO-CPF). The implementation is centered around the concepts of electron pairs and matrix operations. Altogether three cutoff parameters are introduced that control the size of the significant pair list, the average number of PNOs per electron pair, and the number of contributing basis functions per PNO. With the conservatively chosen default values of these thresholds, the method recovers about 99.8% of the canonical correlation energy. This translates to absolute deviations from the canonical result of only a few kcal mol-1. Extended numerical test calculations demonstrate that LPNO-CEPA (LPNO-CPF) has essentially the same accuracy as parent CEPA (CPF) methods for thermochemistry, kinetics, weak interactions, and potential energy surfaces but is up to 500

  13. Boundary Lax pairs from non-ultra-local Poisson algebras

    SciTech Connect

    Avan, Jean; Doikou, Anastasia

    2009-11-15

    We consider non-ultra-local linear Poisson algebras on a continuous line. Suitable combinations of representations of these algebras yield representations of novel generalized linear Poisson algebras or 'boundary' extensions. They are parametrized by a boundary scalar matrix and depend, in addition, on the choice of an antiautomorphism. The new algebras are the classical-linear counterparts of the known quadratic quantum boundary algebras. For any choice of parameters, the non-ultra-local contribution of the original Poisson algebra disappears. We also systematically construct the associated classical Lax pair. The classical boundary principal chiral model is examined as a physical example.

  14. Pair approximation method for spin-1 Heisenberg system

    NASA Astrophysics Data System (ADS)

    Mert, Murat; Kılıç, Ahmet; Mert, Gülistan

    2016-03-01

    Spin-1 Heisenberg system on simple cubic lattice is considered in the pair approximation method assuming that the second-nearest-neighbor exchange interaction parameter has a negative value. The system is described in presence of an external magnetic field. The effects of the negative single-ion anisotropy and the negative second-nearest-neighbor exchange interaction on magnetization, internal energy, heat capacity, entropy and free energy are investigated. There are diverse anomalies at low temperature. In the magnetization and other thermodynamic quantities, the first-order phase transitions from ferromagnetic state to antiferromagnetic state and from ferromagnetic state to paramagnetic state have been observed.

  15. 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.

  16. 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.

  17. Chromosomally-retained RNA mediates homologous pairing.

    PubMed

    Ding, Da-Qiao; Haraguchi, Tokuko; Hiraoka, Yasushi

    2012-01-01

    Pairing and recombination of homologous chromosomes are essential for ensuring correct segregation of chromosomes in meiosis. In S. pombe, chromosomes are first bundled at the telomeres (forming a telomere bouquet) and then aligned by oscillatory movement of the elongated "horsetail" nucleus. Telomere clustering and subsequent chromosome alignment promote pairing of homologous chromosomes. However, this telomere-bundled alignment of chromosomes cannot be responsible for the specificity of chromosome pairing. Thus, there must be some mechanism to facilitate recognition of homologous partners after telomere clustering. Recent studies in S. pombe have shown that RNA transcripts retained on the chromosome, or RNA bodies, may play a role in recognition of homologous chromosomes for pairing. Acting as fiducial markers of homologous loci they would abrogate the need for direct DNA sequence homology searching. PMID:23117617

  18. Atomic Collisions and free Lepton Pair Production

    SciTech Connect

    Gueclue, M.C.; Yilmaz, M.

    2005-10-26

    In this work, we have calculated the total cross sections of electron-positron pair production for the collisions of fully stripped gold ions for various energies. We have also compared our calculation with other methods.

  19. 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.

  20. 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.

  1. A Pair Polarimeter for High Energy Photons

    NASA Astrophysics Data System (ADS)

    Tedeschi, David; Wojtsekhowski, B.; Abbott, D.; Vlahovic, B.; Hotta, T.; Kohri, H.; Matsumura, T.; Mibe, T.; Nakano, T.; Yurita, T.; Zegers, R.; Khandaker, M.; Feldman, G.; O'Rielly, G. V.; Wood, M.; Asai, G.; Rudge, A.; Weilhammer, P.

    2001-10-01

    The physics program at the Thomas Jefferson National Accelerator Facility includes fundamental experiments with polarized photon beams in the GeV energy range. To measure the degree of photon polarization, a photon polarimeter based on the detection of e^+e^- pairs has been developed for use in Hall B and was recently tested at the LEPS facility at SPring-8 in Japan. The use of silicon micro-strip detectors allows for the first time the measurement of the angle correlation in electron-positron pair production by high energy photons incident on an amorphous converter. Theoretical calculations of the pair production process show an asymmetry σ_allel/σ_⊥ ~ 1.7 in a wide range of photon energies. Experimental results from the measurement of the pair asymmetry using 2 GeV photons from the SPring-8 facility will be presented.

  2. 90 Seconds of Discovery: Frustrated Lewis Pairs

    ScienceCinema

    Kathmann, Shawn; Schenter, Greg; Autrey, Tom

    2014-07-21

    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.

  3. Spectra from pair-equilibrium plasmas

    NASA Technical Reports Server (NTRS)

    Zdziarski, A. A.

    1984-01-01

    A numerical model of relativistic nonmagnetized plasma with uniform temperature and electron density distributions is considered, and spectra from plasma in pair equilibrium are studied. A range of dimensionless temperature (T) greater than about 0.2 is considered. The spectra from low pair density plasmas in pair equilibrium vary from un-Comptonized bremsstrahlung spectra at Thomson cross section tau(N) much less than one to Comptonized bremsstrahlung spectra with tau(N) over one. For high pair density plasmas the spectra are flat for T greater than about one, and have broad intensity peaks at energy roughly equal to 3T for T less than one. In the latter region the total luminosity is approximately twice the annihilation luminosity. All spectra are flat in the X-ray region, in contradiction to observed AGN spectra. For dimensionless luminosity greater than about 100, the cooling time becomes shorter than the Thomson time.

  4. Robustness of quantum critical pairing against disorder

    NASA Astrophysics Data System (ADS)

    Kang, Jian; Fernandes, Rafael M.

    2016-06-01

    The remarkable robustness of high-temperature superconductors against disorder remains a controversial obstacle towards the elucidation of their pairing state. Indeed, experiments report a weak suppression rate of the transition temperature Tc with disorder, significantly smaller than the universal value predicted by extensions of the conventional theory of dirty superconductors. However, in many high-Tc compounds, superconductivity appears near a putative magnetic quantum critical point, suggesting that quantum fluctuations, which suppress coherent electronic spectral weight, may also promote unconventional pairing. Here we investigate theoretically the impact of disorder on such a quantum critical pairing state, considering the coupling of impurities both to the low-energy electronic states and to the pairing interaction itself. We find a significant reduction in the suppression rate of Tc with disorder near the magnetic quantum critical point, shedding new light on the nature of unconventional superconductivity in correlated materials.

  5. 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.

  6. 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

  7. 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.

  8. 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

  9. Particle-number-projected thermal pairing

    SciTech Connect

    Nguyen Dinh Dang

    2007-12-15

    Particle-number projection is applied to the modified BCS (MBCS) theory. The resulting particle-number-projected MBCS theory, taking into account the effects due to fluctuations of particle and quasiparticle numbers at finite temperature, is tested within the exactly solvable multilevel model for pairing as well as the realistic {sup 120}Sn nucleus. The signature of the pseudogap in the crossover region above the critical temperature of superfluid-normal phase transition is discussed in terms of the pairing spectral function.

  10. 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.

  11. Paired inhibitory and activating receptor signals.

    PubMed

    Taylor, L S; Paul, S P; McVicar, D W

    2000-01-01

    The immunological literature has become inundated with reports regarding paired inhibitory receptors. Paired inhibitory receptor systems are highly conserved families that contain receptors involved in either cellular inhibition or activation. In most cases the paired putative biochemical antagonists are co-expressed on a given cell and thought to bind similar, if not identical, ligands making their biological role difficult to understand. Examples of these systems include immunoglobulin (Ig)-like receptors (Killer Ig Receptors, Immunoglobulin-like Transcripts/Leukocyte Ig-like Receptors/Monocyte Macrophage Ig Receptors, and Paired Ig-like Receptors), and type II lectin-like receptor systems (NKG2 and Ly49). General characteristics of these inhibitory receptors include a cytoplasmic immunoreceptor tyrosine-based inhibitory motif (ITIM). The ITIM is phosphorylated upon engagement and recruits protein tyrosine phosphatases that dephosphorylate cellular substrates that would otherwise mediate activation. In contrast, the activating receptors of these pairs use charged residues within their transmembrane domains to associate with various signal transduction chains including the gamma chain of the receptor for the Fc portion of IgE, DAP12 or DAP10. Once phosphorylated, these chains direct the signal transduction cascade resulting in cellular activation. Here we review the signaling of several paired systems and present the current models for their signal transduction cascades. PMID:11258418

  12. 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.

  13. Pairing interaction effects in exciton level densities

    SciTech Connect

    Fu, C.Y.

    1989-01-01

    Recent progress in pairing corrections for exciton state-density formulas used in pre-compound nuclear reaction theories is reviewed. These correction factors are, strictly speaking, dependent on the nuclear excitation energy U and the exciton number n. A simple formula for (U,n)-dependent pairing corrections has been derived, based on the BCS pairing equations for constant single-particle spacing, for the exciton state-density formula for one kind of Fermion. It has been shown that the constant-pairing-energy correction used in standard state-density formulas, such U{sub 0} in Gilbert and Cameron, is a limiting case of the general (U,n)-dependent results. Spin cutoff factors with pairing effects were also obtained using the same theory and parameterized into an explicit (U,n)-dependent function, thereby defining a simple exciton level-density formula for applications in quantum mechanical precompound theories. Preliminary results from extending such simple pairing-interaction representations to level-density formulas for two kinds of Fermions are summarized. The results show that the ratios in the exciton level densities in the one-Fermion and two-Fermion approaches vary with both U and n, thus likely leading to differences in calculated compound to precompound ratios. However, the differences in the spin cutoff factors in the two cases are found to be rather small. 12 refs., 3 figs.

  14. 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.

  15. Multipair approach to pairing in nuclei

    NASA Astrophysics Data System (ADS)

    Sambataro, M.

    2012-06-01

    The ground state of a general pairing Hamiltonian for a finite nuclear system is constructed as a product of collective, real, distinct pairs. These are determined sequentially via an iterative variational procedure that resorts to diagonalizations of the Hamiltonian in restricted model spaces. Different applications of the method are provided that include comparisons with exact and projected BCS results. The quantities that are examined are correlation energies, occupation numbers, and pair transfer matrix elements. In a first application within the picket-fence model, the method is seen to generate the exact ground state for pairing strengths confined in a given range. Further applications of the method concern pairing in spherically symmetric mean fields and include simple exactly solvable models as well as some realistic calculations for middle-shell Sn isotopes. In the latter applications, two different ways of defining the pairs are examined: either with J=0 or with no well defined angular momentum. The second choice is revealed to be more effective, leading, under some circumstances, to solutions that are basically exact.

  16. 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.

  17. Low energy (e,2e) studies from CH4: Results from symmetric coplanar experiments and M3DW theory

    NASA Astrophysics Data System (ADS)

    Ch, Haari; Nixon, Kate; Murray, Andrew; Ning, Chuangang; Madison, Don

    2011-05-01

    Low energy experimental and theoretical triply differential cross sections (TDCS) will be presented for electron impact ionization of Methane (CH4) for both the highest occupied molecular orbital (HOMO) and next highest occupied molecular orbital (NHOMO). The HOMO is a predominantly p-type orbital which is labeled 1t2 and the NHOMO is a predominantly s-type orbital labeled 2a1. Coplanar symmetric (symmetric both in final state electron energies and observation angles) will be presented for final state electron energies ranging from (1.4 eV, 1.5 eV) to (20 eV, 20 eV). The experimental results are in reasonably good qualitative agreement with theoretical M3DW (molecular 3-body distorted wave) calculations. The molecular results will be compared with the ionization of the 2s and 2p shells of neon which is the isoelectronic atom. This work was supported by the University of Manchester and the US National Science Foundation under Grant. No. PHY-0757749.

  18. 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.

  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. PMID:20364264

  20. 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.

  1. 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

  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. Influence of deformation on the structure and mechanical and corrosion properties of high-nitrogen austenitic 07Kh16AG13M3 steel

    NASA Astrophysics Data System (ADS)

    Berezovskaya, V. V.; Khadyev, M. S.; Merkushkin, E. A.; Sokolovskaya, Yu. A.

    2013-11-01

    The correlation has been studied between the structure of a high-nitrogen austenitic Cr-Mn-N steel formed in the process of combined hardening treatment, including cold plastic deformation (CPD), and its mechanical and corrosion properties. The structure and properties of commercial high-nitrogen (0.8% N) 07Kh16AG13M3 steel is analyzed after rolling by CPD and aging at 500 and 800°C. It is shown that CPD of the steel occurs by dislocation slip and deformation twinning. Deformation twinning and also high resistance of austenite to martensitic transformations at true strains of 0.2 and 0.4 determine the high plasticity of the steel. The contribution of the structure imperfection parameters to the broadening of the austenite lines during CPD is estimated by X-ray diffraction. The main hardening factor is stated to be lattice microdistortions. Transmission electron microscopy study shows that heating of the deformed steel to 500°C leads to the formation of the intermediate CrN phase by a homogeneous mechanism, and the intermtallic χ phase forms along the austenite grain boundaries in the case of heating at 800°C. After hardening by all investigated technological schemes, exception for aging at 800°C, the steel does not undergo pitting corrosion and is slightly prone to a stress corrosion cracking during static bending tests, while aging at 800°C causes pitting corrosion at a pitting formation potential E pf = -0.25 V.

  4. 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

  5. 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

  6. Autoantibodies against the Second Extracellular Loop of M3R Do neither Induce nor Indicate Primary Sjögren’s Syndrome

    PubMed Central

    Chen, Yan; Zheng, Junfeng; Huang, Qiaoniang; Deng, Fengyuan; Huang, Renliang; Zhao, Wenjie; Yin, Junping; Song, Lina; Chen, Juan; Gao, Xing; Liu, Zuguo; Petersen, Frank; Yu, Xinhua

    2016-01-01

    Objectives Anti-muscarinic acetylcholine type-3 receptor (anti-M3R) autoantibodies have been suggested to be pathogenic for primary Sjögren’s syndrome (pSS), and the second extracellular loop of M3R is suspected to carry a disease-promoting epitope. In this study, we aimed to evaluate the pathogenicity of autoantibodies against peptides derived from the second extracellular loop of M3R in mice and to determine whether those autoantibodies could be used as biomarker for pSS. Methods BALB/c mice were immunized with modified linear or cyclic peptides of the second extracellular loop of M3R. The function of exocrine glands was evaluated by measuring the secretion of saliva and tears. The histological evaluations were performed by using H&E staining or direct immunofluorescence staining. Autoantibodies against linear or cyclic peptides of the second extracellular loop of M3R in human and mice were determined using ELISA. Results Immunization induced mice to produce autoantibodies against the linear or cyclic peptides of the second extracellular loop of M3R, and those autoantibodies could bind onto salivary glands. However, those mice showed neither impairment in the secretion of tears or saliva nor histological abnormality in the exocrine glands. Furthermore, passive transfer of the IgG isolated from the immunized mice into healthy mice did not induced the dysfunction of the exocrine glands. The prevalence of autoantibodies against the peptides of the second extracellular loop of M3R was low in pSS patients, and it did not differ significantly from that in healthy controls. Conclusions Our results suggest that the autoantibodies against peptides of the second extracellular loop of M3R are not pathogenic in vivo and they are not suitable as biomarkers for pSS diagnosis. PMID:26901532

  7. 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.

  8. Salmonella enterica Serotype Gambia with CTX-M-3 and armA Resistance Markers: Nosocomial Infections with a Fatal Outcome▿

    PubMed Central

    Moissenet, D.; Weill, F.-X.; Arlet, G.; Harrois, D.; Girardet, J. P.; Vu-Thien, H.

    2011-01-01

    We report two cases of bacteremia caused by the Salmonella enterica serotype Gambia in our children's hospital, with one fatal outcome. The isolates showed indistinguishable genotypes and infrequent resistance markers: CTX-M-3 extended-spectrum β-lactamase and armA methyltransferase. This is the first report of S. Gambia exhibiting CTX-M-3 and armA markers involved in serious infections. PMID:21270227

  9. 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

  10. 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

  11. 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

  12. Modeling the initial conditions of interacting galaxy pairs using Identikit

    NASA Astrophysics Data System (ADS)

    Mortazavi, S. Alireza; Lotz, Jennifer M.; Barnes, Joshua E.; Snyder, Gregory F.

    2016-01-01

    We develop and test an automated technique to model the dynamics of interacting galaxy pairs. We use Identikit as a tool for modelling and matching the morphology and kinematics of the interacting pairs of equal-mass galaxies. In order to reduce the effect of subjective human judgement, we automate the selection of phase space regions used to match simulations to data, and we explore how selection of these regions affects the random uncertainties of parameters in the best-fitting model. In this work, we use an independent set of GADGET SPH simulations as input data to determine the systematic bias in the measured encounter parameters based on the known initial conditions of these simulations. We test both cold gas and young stellar components in the GADGET simulations to explore the effect of choosing H I versus H α as the line-of-sight velocity tracer. We find that we can group the results into tests with good, fair, and poor convergence based on the distribution of parameters of models close to the best-fitting model. For tests with good and fair convergence, we rule out large fractions of parameter space and recover merger stage, eccentricity, pericentric distance, viewing angle, and initial disc orientations within 3σ of the correct value. All of tests on prograde-prograde systems have either good or fair convergence. The results of tests on edge-on discs are less biased than face-on tests. Retrograde and polar systems do not converge and may require constraints from regions other than the tidal tails and bridges.

  13. 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.

  14. Constructing optimal backbone segments for joining fixed DNA base pairs.

    PubMed Central

    Mazur, J; Jernigan, R L; Sarai, A

    1996-01-01

    A method is presented to link a sequence of space-fixed base pairs by the sugar-phosphate segments of single nucleotides and to evaluate the effects in the backbone caused by this positioning of the bases. The entire computational unit comprises several nucleotides that are energy-minimized, subject to constraints imposed by the sugar-phosphate backbone segments being anchored to space-fixed base pairs. The minimization schemes are based on two stages, a conjugate gradient method followed by a Newton-Raphson algorithm. Because our purpose is to examine the response, or relaxation, of an artificially stressed backbone, it is essential to be able to obtain, as closely as possible, a lowest minimum energy conformation of the backbone segment in conformational space. For this purpose, an algorithm is developed that leads to the generation of an assembly of many local energy minima. From these sets of local minima, one conformation corresponding to the one with the lowest minimum is then selected and designated to represent the backbone segment at its minimum. The effective electrostatic potential of mean force is expressed in terms of adjustable parameters that incorporate solvent screening action in the Coulombic interactions between charged backbone atoms; these parameters are adjusted to obtain the best fit of the nearest-neighbor phosphorous atoms in an x-ray structure. PMID:8874023

  15. Non-hydrolytic sol-gel synthesis and characterization of materials of the type AA'M3O12

    NASA Astrophysics Data System (ADS)

    Baiz, Tamam Issa

    In recent years, there has been an increased interest in negative thermal expansion (NTE) materials, which contract upon heating. Materials exhibiting this property have the potential for achieving better control of thermal expansion through the synthesis of composite materials with more desirable expansion coefficients. By introducing NTE materials into these composites, it is possible to offset the positive thermal expansion of other components in the composite. As a result, these NTE materials can find use in a wide range of applications such as optics, electronics, tooth fillings and any other area where exact positioning of parts over a wide range of temperatures is crucial. A family of materials that has been known to show NTE are A 2M3O12 compounds, where A can be a variety of trivalent cations and M can be Mo or W. Previous work on this system has shown that the thermal expansion is highly dependent on the type of trivalent cation employed. However, in spite of the interest in these A2M3O 12 compounds, little research has been dedicated to synthesizing materials containing two aliovalent cations instead of just one or two trivalent cations. In fact, the first example of a heterosystem with +2 and +4 cations was not reported until 2004. This dissertation presents results of investigation and characterization of these mixed cation systems, and the change in the thermal expansion properties. The first goal of the research presented herein was to synthesize mixed cation systems using a lower temperature route, and then compare the materials synthesized using low temperature methods with those synthesized using the ball-milling method. This will ensure the validity of applying a lower temperature method to these mixed cation systems. A non-hydrolytic sol-gel (NHSG) method was used, which is based on the reaction of metal alkoxides with metal halides to form M-O-M linkages, with alkyl halides as byproducts. With this method, MgHfW3O12 and MgZrW3O 12 were

  16. Estimators for overdetermined linear Stokes parameters

    NASA Astrophysics Data System (ADS)

    Furey, John

    2016-05-01

    The mathematics of estimating overdetermined polarization parameters is worked out within the context of the inverse modeling of linearly polarized light, and as the primary new result the general solution is presented for estimators of the linear Stokes parameters from any number of measurements. The utility of the general solution is explored in several illustrative examples including the canonical case of two orthogonal pairs. In addition to the actual utility of these estimators in Stokes analysis, the pedagogical discussion illustrates many of the considerations involved in solving the ill-posed problem of overdetermined parameter estimation. Finally, suggestions are made for using a rapidly rotating polarizer for continuously updating polarization estimates.

  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. 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

  19. 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

  20. Terminal Area Procedures for Paired Runways

    NASA Technical Reports Server (NTRS)

    Lozito, Sandy

    2011-01-01

    Parallel Runway operations have been found to increase capacity within the National Airspace (NAS) however, poor visibility conditions reduce this capacity [1]. Much research has been conducted to examine the concepts and procedures related to parallel runways however, there has been no investigation of the procedures associated with the strategic and tactical pairing of aircraft for these operations. This study developed and examined the pilot and controller procedures and information requirements for creating aircraft pairs for parallel runway operations. The goal was to achieve aircraft pairing with a temporal separation of 15s(+/- 10s error) at a coupling point that is about 12 nmi from the runway threshold. Two variables were explored for the pilot participants: Two levels of flight deck automation (current-day flight deck automation, and a prototype future automation) as well as two flight deck displays that assisted in pilot conformance monitoring. The controllers were also provided with automation to help create and maintain aircraft pairs. Data showed that the operations in this study were found to be acceptable and safe. Workload when using the pairing procedures and tools was generally low for both controllers and pilots, and situation awareness (SA) was typically moderate to high. There were some differences based upon the display and automation conditions for the pilots. Future research should consider the refinement of the concepts and tools for pilot and controller displays and automation for parallel runway concepts.

  1. 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.

  2. Pair creation of black holes during inflation

    NASA Astrophysics Data System (ADS)

    Bousso, Raphael; Hawking, Stephen W.

    1996-11-01

    Black holes came into existence together with the universe through the quantum process of pair creation in the inflationary era. We present the instantons responsible for this process and calculate the pair creation rate from the no boundary proposal for the wave function of the universe. We find that this proposal leads to physically sensible results, which fit in with other descriptions of pair creation, while the tunneling proposal makes unphysical predictions. We then describe how the pair-created black holes evolve during inflation. In the classical solution, they grow with the horizon scale during the slow roll down of the inflaton field; this is shown to correspond to the flux of field energy across the horizon according to the first law of black hole mechanics. When quantum effects are taken into account, however, it is found that most black holes evaporate before the end of inflation. Finally, we consider the pair creation of magnetically charged black holes, which cannot evaporate. In standard Einstein-Maxwell theory we find that their number in the presently observable universe is exponentially small. We speculate how this conclusion may change if dilatonic theories are applied.

  3. 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

  4. Pairing in a dry Fermi sea

    DOE PAGESBeta

    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

  5. Electron pair emission from surfaces: Intensity relations

    NASA Astrophysics Data System (ADS)

    Schumann, F. O.; Aliaev, Y.; Kostanovskiy, I.; Di Filippo, G.; Wei, Z.; Kirschner, J.

    2016-06-01

    The emission of an electron pair upon single-photon absorption requires a finite electron-electron interaction. Therefore, double photoemission is a particularly sensitive tool to study the electron correlation in matter. This is supported by a recent theoretical work which predicts that the pair intensity is a direct reflection of the correlation strength. In order to explore the validity of this statement, we performed a study on a variety of materials. Among them are noble metals, transition metals, and insulators. The latter include transition metal oxides such as CoO and NiO which are also termed highly correlated. We find an increased pair emission rate of NiO and CoO compared to the metals which reach a factor of 10. We also discovered that an increase of the coincidence intensity is accompanied by an increase in the singles count rate. This demonstrates that the electron pair emission is an efficient process at surfaces contributing up to 15 % to the single-electron emission in double photoemission. We performed also electron pair emission studies upon primary electron impact and find similar intensity relations.

  6. 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.

  7. Cooper-pair splitter: towards an efficient source of spin-entangled EPR pairs

    NASA Astrophysics Data System (ADS)

    Schonenberger, Christian

    2011-03-01

    In quantum mechanics the properties of two and more particles can be entangled. In basic science pairs of entangled particles, so called Einstein-Podolsky-Rosen (EPR) pairs, play a special role as toy objects for fundamental studies. They provide such things as ``spooky interaction at distance,'' but they also enable secure encoding and teleportation and are thus important for applications in quantum information technology. Whereas EPR pairs of photons can be generated by parametric down conversion (PDC) in a crystal, a similar source for EPR pairs of electrons does not exists yet. In several theory papers, it has been suggested to use a superconductor for this purpose. The superconducting ground state is formed by a condensate of Cooper-pairs which are electron pairs in a spin-singlet state. Since there are many Cooper pairs in a metallic superconductor like Al, the main tasks are to extract Cooper pairs one by one and to split them into different arms. A controlled and efficient splitting is possible if one makes use of Coulomb interaction. This has recently be demonstrated by two groups [2-4] using hybrid quantum-dot devices with both superconducting and normal metal contacts. In the present talk, I will discuss the Cooper-pair splitter results from the Basel-Budapest-Copenhagen team and compare with the other experiments. As an outlook we discuss approaches that aim at entanglement detection. The Cooper pair splitter holds great promises because very large splitting efficiencies approaching 100% and large pair current rates appear feasible. This work has been done by L. Hofstetter, S. Csonka, A. Geresdi, M. Aagesen, J. Nygard and C. Schönenberger

  8. Thermodynamics of the formation of Ag(I)-mediated azole base pairs in DNA duplexes.

    PubMed

    Schweizer, Kristina; Léon, J Christian; Ravoo, Bart Jan; Müller, Jens

    2016-07-01

    Isothermal titration calorimetry was applied to determine the thermodynamic parameters for the specific binding of Ag(I) ions to a series of DNA duplexes comprising Im:Im or Tr:Tr mispairs to form metal-mediated Im-Ag(I)-Im or Tr-Ag(I)-Tr base pairs (Im=imidazole nucleoside; Tr=1.2,4-triazole nucleoside). A total of seven different duplexes are discussed, incorporating one to three artificial base pairs in neighboring or non-neighboring positions. The association constant related to the formation of Tr-Ag(I)-Tr base pairs is estimated to be <10(3)M(-1). In contrast, Im-Ag(I)-Im base pairs are much more stable. The intrinsic association constant for their formation is in the order of 10(6)M(-1) and is therefore larger than that for the formation of T-Hg(II)-T and C-Ag(I)-C base pairs consisting of natural nucleobases. Two neighboring Im-Ag(I)-Im base pairs form cooperatively, whereas two remotely located Im-Ag(I)-Im base pairs form non-cooperatively. In general, the specific binding of Ag(I) to Im:Im-containing duplexes is enthalpically driven, with a significant additional entropic contribution in most cases. PMID:27032292

  9. 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.

  10. Entropy, area, and black hole pairs

    NASA Astrophysics Data System (ADS)

    Hawking, S. W.; Horowitz, Gary T.; Ross, Simon F.

    1995-04-01

    We clarify the relation between gravitational entropy and the area of horizons. We first show that the entropy of an extreme Reissner-Nordström black hole is zero, despite the fact that its horizon has nonzero area. Next, we consider the pair creation of extremal and nonextremal black holes. It is shown that the action which governs the rate of this pair creation is directly related to the area of the acceleration horizon and (in the nonextremal case) the area of the black hole event horizon. This provides a simple explanation of the result that the rate of pair creation of nonextreme black holes is enhanced by precisely the black hole entropy. Finally, we discuss black hole annihilation, and argue that Planck scale remnants are not sufficient to preserve unitarity in quantum gravity.

  11. Thermodynamics of pairing transition in hot nuclei

    NASA Astrophysics Data System (ADS)

    Liu, Lang; Zhang, Zhen-Hua; Zhao, Peng-Wei

    2015-10-01

    The pairing correlations in hot nuclei 162Dy are investigated in terms of the thermodynamical properties by covariant density functional theory. The thermodynamical quantities are evaluated by the canonical ensemble theory and the paring correlations are treated by a shell-model-like approach, in which the particle number is conserved exactly. An S-shaped heat capacity curve as a function of temperature has been obtained. The properties of hot nuclei, such as entropy and level density are studied in terms of defined seniority component. It is found that the one-pair-broken states play crucial roles in the appearance of the S shape of the heat capacity curve. Moreover, due to the effect of the particle-number conservation, the pairing gap varies smoothly with the temperature, which indicates a gradual transition from the superfluid to the normal state.

  12. A Pair Polarimeter for High Energy Photons

    NASA Astrophysics Data System (ADS)

    Tedeschi, David; Wojtsekhowski, B.; Khandaker, M.; Klein, F.; Feldman, G.; O'Rielly, G. V.; Vlahovic, B.

    2000-10-01

    The physics program at the Thomas Jefferson National Accelerator Facility includes fundamental experiments with polarized photon beams in the GeV energy range. To measure the degree of photon polarization, a photon polarimeter based on the detection of e^+e^- pairs has been developed for use in Hall B experiments. Recent progress in silicon micro-strip detectors allows for the measurement of the angle correlation in electron-positron pair production by high energy photons incident on an amorphous converter. Theoretical calculations of the pair production process show an asymmetry σ_allel/σ_⊥ ~ 1.7 in a wide range of photon energies. Experimental results obtained from 40 MeV photons at the Duke-FEL and 300 MeV photons from the Brookhaven-LEGS facility using prototype polarimeters will be presented.

  13. Hard Photodisintegration of a Proton Pair

    SciTech Connect

    Pomerantz, Ishay; Bubis, Nathaniel; Allada, Kalyan; Beck, Arie; Beck, Sara; Berman, Barry L.; Boeglin, Werner U.; Camsonne, Alexandre; Canan, Mustafa; Chirapatpimol, Khem; Cisbani, Evaristo; Cusanno, Francesco; de Jager, Cornelis W.; Dutta, Chirajib; Garibaldi, Franco; Geagla, Octavian; Gilman, Ronald; Glister, Jacqueline F.; Higinbotham, Douglas W.; Jiang, Xiaodong; Katramatou, A. T.; Khrosinkova, Elena; Lee, B. W.; LeRose, John J.; Lindgren, Richard A.; McCullough, Emily; Meekins, David G.; Michaels, Robert W.; Moffit, Bryan J.; Petratos, Gerassimos G.; Piasetzky, Eliazer I.; Qian, Xin; Qiang, Yi; Rodriguez, I.; Ron, Guy; Saha, Arun; Sarty, Adam J.; Sawatzky, Bradley D.; Schulte, Elaine C.; Shneor, Ran; Sparveris, NIkolaos; Subedi, Ramesh R.; Sulkosky, Vincent A.; Wang, Y.; Wojtsekhowski, Bogdan B.; Yan, X.; Yao, H.; Zhan, Xiaohui; Zheng, Xiaochao

    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 strong energy-dependent structure not observed in deuteron photodisintegration.

  14. Hard Photodisintegration of a Proton Pair

    DOE PAGESBeta

    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

  15. Induced Pairing Interaction in Neutron Star Matter

    NASA Astrophysics Data System (ADS)

    Lombardo, U.; Schulze, H.-J.; Zuo, W.

    2013-01-01

    The three superfluid phases supposed to occur in neutron stars are reviewed in the framework of the generalized BCS theory with the induced interaction. The structure of neutron stars characterized by beta-stable asymmetric nuclear matter in equilibrium with the gravitational force discloses new aspects of the pairing mechanism. Some of them are discussed in this report, in particular the formation in dense matter of Cooper pairs in the presence of three-body forces and the interplay between repulsive and attractive polarization effects on isospin T = 1 Cooper pairs embedded into the neutron and proton environment. Quantitative estimates of the energy gaps are reported and their sensitivity to the medium effects, i.e., interaction and polarization, is explored.

  16. Automated DNA Base Pair Calling Algorithm

    Energy Science and Technology Software Center (ESTSC)

    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

  17. 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.

  18. 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

  19. Interrelations between the pairing and quadrupole interactions in the microscopic Shell Model

    NASA Astrophysics Data System (ADS)

    Drumev, K. P.; Georgieva, A. I.

    2016-01-01

    We explore the dynamical symmetries of the shell model number conserving algebra, which define three types of pairing and quadrupole phases, with the aim to obtain the prevailing phase or phase transition for the real nuclear systems in a single shell. This is achieved by establishing a correspondence between each of the pairing bases with the Elliott's SU(3) basis that describes collective rotation of nuclear systems. This allows for a complete classification of the basis states of different number of particles in all the limiting cases. The probability distribution of the SU(3) basis states within theirs corresponding pairing states is also obtained. The relative strengths of dynamically symmetric quadrupole-quadrupole interaction in respect to the isoscalar, isovector and total pairing interactions define a control parameter, which estimates the importance of each term of the Hamiltonian in the correct reproduction of the experimental data for the considered nuclei.

  20. Photon pair generation from compact silicon microring resonators using microwatt-level pump powers.

    PubMed

    Savanier, Marc; Kumar, Ranjeet; Mookherjea, Shayan

    2016-02-22

    Microring resonators made from silicon are becoming a popular microscale device format for generating photon pairs at telecommunications wavelengths at room temperature. In compact devices with a footprint less than 5 × 10-4 mm2, we demonstrate pair generation using only a few microwatts of average pump power. We discuss the role played by important parameters such as the loss, group-velocity dispersion and the ring-waveguide coupling coefficient in finding the optimum operating point for silicon microring pair generation. Silicon photonics can be fabricated using deep ultraviolet lithography wafer-scale fabrication processes, which is scalable and cost-effective. Such small devices and low pump power requirements, and the side-coupled waveguide geometry which uses an integrated waveguide, could be beneficial for future scaled-up architectures where many pair-generation devices are required on the same chip. PMID:26906993

  1. Compositional Survey of Central Peaks in the South Pole-Aitken Basin from Moon Mineralogy Mapper (M3) data

    NASA Astrophysics Data System (ADS)

    Isaacson, P.; Nettles, J.; Boardman, J. W.; Petro, N. E.; Klima, R. L.; Taylor, L. A.; Pieters, C. M.; Cheek, L.; Clark, R. N.; Head, J. W.; Whitten, J.; Tompkins, S.; Besse, S.; Dhingra, D.; Moriarty, D.; Moon Mineralogy Mapper Team

    2010-12-01

    Orbital measurements allow the composition of planetary surfaces to be mapped globally, something not possible with returned samples. Optical instruments such as reflectance spectrometers, which are sensitive to the very uppermost surface (~1-2 mm depth), provide the highest spatial resolution of the various compositional remote sensing techniques. Major lunar rock-forming minerals exhibit diagnostic absorptions across visible to near-infrared (VNIR) wavelengths, and data returned by VNIR reflectance spectrometers can use these absorptions to map lunar mineralogy. However, on the Moon, much of the surface is dominated by mature lunar soils formed by the continual bombardment of the lunar surface over geologic time. This weathering process effectively weakens diagnostic mineral absorption features, complicating mineralogical analyses. Focused analyses of central peaks eliminate two of the drawbacks of remote VNIR reflectance spectroscopy. The steep slopes of central peaks inhibit the development of a thick regolith layer, meaning that central peaks are relatively optically immature and thus preserve the diagnostic spectral absorption features critical to compositional analyses. Furthermore, the crater formation process excavates materials from depth [e.g., Melosh, 1989, Cintala and Grieve, 1998], exposing materials that would otherwise be inaccessible to optical remote sensing. We are in the midst of a survey of lunar crater central peaks with Moon Mineralogy Mapper (M3) data, following the work of Tompkins and Pieters [1999], who used Clementine UVVIS multispectral data. We employ a band fitting procedure that gives estimates of the position, strength, and width of the mafic 1 μm absorption feature, which are used to evaluate the mineralogy of the central peaks. Within SPA are a number of craters of various sizes with well defined central peaks (e.g,. Bhabha, Fizeau, Finsen, Dryden) that presumably tap multiple depths across SPA, which itself excavated material

  2. 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.

  3. 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.

  4. 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…

  5. 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

  6. Pairing Content and Process: Some Observations.

    ERIC Educational Resources Information Center

    Fillenworth, Ceil; Rauch, Margaret

    Although a college program to retain high risk freshmen--those who fall below the 50th percentile of their graduating class--can result in increased academic success, a number of concerns must be addressed. The structure of one such program contains three components: the paired course curriculum, a career planning and personal goal exploration…

  7. RNA Matchmaking: Finding Cellular Pairing Partners.

    PubMed

    Graveley, Brenton R

    2016-07-21

    RNA structure is intimately related to function, yet methods to identify base-paired RNA strands in a transcriptome-wide manner in cells have remained elusive. One recent paper in Cell and two in Molecular Cell describe related methods to identify RNA sequences that interact in living cells, setting the stage for breakthroughs in our understanding of RNA structure and function. PMID:27447984

  8. Chemical Nonlinearities and Radical Pair Lifetime Estimation

    NASA Astrophysics Data System (ADS)

    Robinson, Gregory

    2013-03-01

    Much attention has recently developed around chemical reactions that depend on applied static magnetic fields as weak as earth's. This interest is largely motivated by experiments that implicate the role of spin-selective radical pair recombination in biological magnetic sensing. Existing literature uses a straightforward calculation to approximate the expected lifetime of coherent radical pairs as a function of the minimum RF amplitude that is observed to disrupt magnetic navigation, apparently by decohering the radical pair via electronic Zeeman excitations. But we show that chemical nonlinearities can preclude direct computation of coherent pair lifetime without considering the cellular signalling mechanisms involved, and discuss whether it can explain the surprising fragility of some animals' compass sense. In particular, we demonstrate that an autocatalytic cycle can introduce threshold effects on the disruption sensitivity to applied oscillatory magnetic fields. We will show examples in the mean-field limit and consider the consequences of noise and fluctuations in the Freidlin-Wentzell picture of perturbed dynamical systems.

  9. The Paired-Object Affordance Effect

    ERIC Educational Resources Information Center

    Yoon, Eun Young; Humphreys, Glyn W.; Riddoch, M. Jane

    2010-01-01

    We demonstrate that right-handed participants make speeded classification responses to pairs of objects that appear in standard co-locations for right-handed actions relative to when they appear in reflected locations. These effects are greater when participants "weight" information for action when deciding if 2 objects are typically used…

  10. 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…

  11. Promoting Paired Placements in Initial Teacher Education

    ERIC Educational Resources Information Center

    King, Sheila

    2006-01-01

    The use of paired placements and collaborative practice is promoted by many university-school partnerships that train teachers in England. This paper reviews the recent literature on the subject and then focuses on some small scale research within initial teacher education in one large university-school partnership. That partnership works with…

  12. Pairing, pseudogap and Fermi arcs in cuprates

    DOE PAGESBeta

    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

  13. 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

  14. Plasma analog of particle-pair production

    SciTech Connect

    Tsidulko, Yu.A.; Berk, H.L.

    1996-09-01

    It is shown that the plasma axial shear flow instability satisfies the Klein-Gordon equation. The plasma instability is then shown to be analogous to spontaneous particle-pair production when a potential energy is present that is greater than twice the particle rest mass energy. Stability criteria can be inferred based on field theoretical conservation laws.

  15. 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.

  16. Two New CPM Pairs in Libra

    NASA Astrophysics Data System (ADS)

    Ahad, Abdul

    2014-10-01

    In this paper two new double stars are reported in the constellation of Libra that are currently not in the WDS catalog, the components of which share common proper motions. On observed photometric characteristics, calibration of distances, and other assumptions, all the indications are that both pairs comprise possible wide physical systems.

  17. 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.…

  18. 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.

  19. 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.

  20. 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

  1. 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…

  2. Two-photon production of ω pairs

    NASA Astrophysics Data System (ADS)

    Albrecht, H.; Hamacher, T.; Hofmann, R. P.; Kirchhoff, T.; Mankel, R.; Nau, A.; Nowak, S.; Reßing, D.; Schröder, H.; Schulz, H. D.; Walter, M.; Wurth, R.; Hast, C.; Kapitza, H.; Kolanoski, H.; Kosche, A.; Lange, A.; Lindner, A.; Schieber, M.; Siegmund, T.; Spaan, B.; Thurn, H.; Töpfer, D.; Wegener, D.; Eckstein, P.; Frankl, C.; Graf, J.; Schmidtler, M.; Schramm, M.; Schubert, K. R.; Schwierz, R.; Waldi, R.; Reim, K.; Wegener, H.; Eckmann, R.; Kuipers, H.; Mai, O.; Mundt, R.; Oest, T.; Reiner, R.; Schmidt-Parzefall, W.; Stiewe, J.; Werner, S.; Ehret, K.; Hofmann, W.; Hüpper, A.; Knöpfle, K. T.; Spengler, J.; Krieger, P.; Macfarlane, D. B.; Prentice, J. D.; Saull, P. R. B.; Tzamariudaki, K.; van de Water, R. G.; Yoon, T.-S.; Schneider, M.; Weseler, S.; Kernel, G.; Križan, P.; Križnič, E.; Podobnik, T.; Živko, T.; Balagura, V.; Barsuk, S.; Belyaev, I.; Chistov, R.; Danilov, M.; Eiges, V.; Gershtein, L.; Gershtein, Yu.; Golutvin, A.; Igonkina, O.; Korolko, I.; Kostina, G.; Litvintsev, D.; Pakhlov, P.; Semenov, S.; Snizhko, A.; Tichomirov, I.; Zaitsev, Yu.; Argus Collaboration

    1996-02-01

    A maximum likelihood analysis of ARGUS data on two-photon production of π+π+π0π0π-π- is presented. A small fraction of events is due to the production of omega pairs. The γγ → ωω cross section has its maximum value close to threshold.

  3. Relaxed States in Magnetized Pair Plasmas

    NASA Astrophysics Data System (ADS)

    Shukla, P. K.; Mahajan, S. M.

    2004-01-01

    We discuss possibility of possible relaxed states in magnetized pair plasmas. It is shown that stationary relaxed states are described by the double curl Beltrami/Mahajan-Yoshida equation. We can thus have steady state tructures on the scale sizes of the order of the electron (ion) skin depth in an electron-positron (electron-positron-ion) plasma.

  4. LUNAR SURFACE COMPOSITIONAL UNITS DETERMINED BY SPECTRAL MIXING ANALYSIS OF IMAGES FROM THE MOON MINERALOGY MAPPER (M3)

    NASA Astrophysics Data System (ADS)

    Combe, J.; Kramer, G. Y.; McCord, T. B.; Taylor, L. A.; Petro, N. E.; Pieters, C. M.; Boardman, J. W.; Mustard, J. F.; Sunshine, J. M.; Tompkins, S.

    2009-12-01

    Mapping-surface compositional units on large areas of the Moon is a key step for interpretating its geology. In addition, the spatial distribution and relative abundances of minerals and glasses are essential for the study of mixing processes and maturation of the soil. We are using data from the M3 imaging spectrometer [1], which was in lunar orbit onboard Chandrayaan-1 for 10 months starting in November 2008. In global observation mode [1], the spectral range is 460-2976 nm at 20 and 40 nm spectral resolution, and the spatial resolution is 140 m/pixel or 280 m/pixel. Spectral Mixing Analysis (SMA) is one method for calculating abundances of spectral components (endmembers) mixed within a surface-projected pixel [2-8]. Spectra are modeled by linear combinations of the spectral endmembers, which correspond to adjacent areas of different compositions present within the same pixel. The inversion (unmixing) of this simple physical model is convenient for an initial assessment of large data sets prior to using more sophisticated methods for compositional analysis [7-9]. In the present study, the spectral endmembers are collected from the image that will be unmixed using two ways of selection in order to arrive at the most effective ones: 1) Among the representative nearside mare compositions defined by [10], we chose the most-extreme spectra, based on their absorption bands and on the titanium content of the corresponding lunar samples. 2) Using our own iterative approach, we start with the two most-representative spectra of mature highlands and mature mare soils as input for the SMA. Then, we analyze the residuals of the SMA to define more endmembers. We perform SMA using the Multiple-Endmember Linear Spectral-Unmixing Model (MELSUM, [8, 11]) that allows limiting the number of components used in a model and guarantees positive mixing coefficients. Shade is assumed to have a neutral (flat) spectral contribution. The sum of the mixing coefficients is constrained to

  5. Electronic excited-state behavior of rhodamine 3B in AOT reverse micelles sensing contact ion pair to solvent separated ion pair interconversion.

    PubMed

    Ferreira, José A B; Costa, Sílvia M B

    2010-08-19

    The amphiphile Aerosol OT (1,4-bis(2-ethylhexyl)sodium sulfosuccinate, AOT) forms, in reverse micellar nanoaggregates of water, RM, in isooctane, ion pairs (IPs) with the cationic fluorescent probe dye, rhodamine 3B, (3,6-bis(ethylamino)-9-[2-(ethoxycarbonyl)phenyl]-9H-xanthen-9-ylium, R3B), as either contact ion pairs, CIPs, or solvent (water) separated ion pairs, SSIPs. The ground-state AOT R3B ion pairs' equilibria as well as the dynamics of R3B electronic excited states show the progressive hydration of AOT(-) R3B(+) toward solvent separated ion pairs, SSIPs as the characteristic reverse micelle parameter w(0) = [H(2)O]/[AOT] increases. The apparent limiting hydration constant of R3B ion pairs, K(hyd) = 2.8 +/- 0.2, corresponds to full hydration of AOT, consistent with 1-3 water molecules per AOT polar head. Transient relaxations at w(0) = 0.2, with a 375 +/- 15 ps decay at 550 nm decrease to 115 +/- 15 ps at w(0) = 7.2 turning into corresponding rises at 588 nm. At higher w(0), water induced dynamics becomes faster. The lifetime is longer in RM with smaller w(0), due to the presence of CIPs that inhibit intrinsic nonradiative decay processes, which in contrast shorten the decay times at higher w(0), due to the presence of SSIPs. The pairs' electronic excited-state properties are sensitive to viscosity and local polarity of the surrounding environment of the interfacial regions of AOT reverse micellar nanoaggregates. PMID:20666438

  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. Hydrologic calibration of paired watersheds using a MOSUM approach

    DOE PAGESBeta

    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

  8. Radical loss of an extreme extra-pair mating system

    PubMed Central

    Kingma, Sjouke A; Hall, Michelle L; Segelbacher, Gernot; Peters, Anne

    2009-01-01

    Background Mating outside the pair-bond is surprisingly common in socially monogamous birds, but rates of extra-pair paternity (EPP) vary widely between species. Although differences in life-history and contemporary ecological factors may explain some interspecific variation, evolutionary forces driving extra-pair (EP) mating remain largely obscure. Also, since there is a large phylogenetic component to the frequency of EPP, evolutionary inertia may contribute substantially to observed EP mating patterns. However, the relative importance of plasticity and phylogenetic constraints on the incidence of EP mating remains largely unknown. Results We here demonstrate very low levels of EPP (4.4% of offspring) in the purple-crowned fairy-wren Malurus coronatus, a member of the genus with the highest known levels of EPP in birds. In addition, we show absence of the suite of distinctive behavioral and morphological adaptations associated with EP mating that characterize other fairy-wrens. Phylogenetic parsimony implies that these characteristics were lost in one speciation event. Nonetheless, many life-history and breeding parameters that are hypothesized to drive interspecific variation in EPP are not different in the purple-crowned fairy-wren compared to its promiscuous congeners. Conclusion Such radical loss of an extreme EP mating system with all associated adaptations from a lineage of biologically very similar species indicates that evolutionary inertia does not necessarily constrain interspecific variation in EPP. Moreover, if apparently minor interspecific differences regularly cause large differences in EPP, this may be one reason why the evolution of EP mating is still poorly understood. PMID:19454026

  9. Hydrologic calibration of paired watersheds using a MOSUM approach

    NASA Astrophysics Data System (ADS)

    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.

    2015-01-01

    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.

  10. 40 CFR Table F-3 to Subpart F of... - Critical Parameters of Idealized Ambient Particle Size Distributions

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    .... (µg/m3) Coarse Particle Mode MMD (µm) Geo. Std. Dev. Conc. (µg/m3) PM2.5/PM10 Ratio FRM Sampler... EQUIVALENT METHODS Procedures for Testing Performance Characteristics of Class II Equivalent Methods for PM2.5 Pt. 53, Subpt. F, Table F-3 Table F-3 to Subpart F of Part 53—Critical Parameters of...

  11. 40 CFR Table F-3 to Subpart F of... - Critical Parameters of Idealized Ambient Particle Size Distributions

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    .... (µg/m3) Coarse Particle Mode MMD (µm) Geo. Std. Dev. Conc. (µg/m3) PM2.5/PM10 Ratio FRM Sampler... 40 Protection of Environment 5 2011-07-01 2011-07-01 false Critical Parameters of Idealized... EQUIVALENT METHODS Procedures for Testing Performance Characteristics of Class II Equivalent Methods for...

  12. 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

  13. Fixed-Parameter Algorithm for General Pedigrees with a Single Pair of Sites

    NASA Astrophysics Data System (ADS)

    Doan, Duong D.; Evans, Patricia A.

    The problem of computing the minimum number of recombination events for general pedigrees with two sites for all members is investigated. We show that this NP-hard problem can be parametrically reduced to the Bipartization by Edge Removal problem and therefore can be solved by an O(2 k ·n 2) exact algorithm, where n is the number of members and k is the number of recombination events.

  14. On the wobble GoU and related pairs.

    PubMed Central

    Masquida, B; Westhof, E

    2000-01-01

    The wobble GoU pairs have been implicated in several biological processes where RNA molecules play a key role. We review the geometrical and conformational properties of wobble GoU pairs on the basis of available crystal structures of RNAs at high resolution. The similarities with the wobble A+oC pairs and UoU pairs are illustrated, while the differences with the recently discovered bifurcated G x U pairs are contrasted. PMID:10668794

  15. 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.

  16. 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.

  17. Auditory detection of paired pulses by a dolphin in the presence of a pulse jam

    NASA Astrophysics Data System (ADS)

    Sukhoruchenko, M. N.

    2004-07-01

    From behavioral studies of a bottlenose dolphin ( Tursiops truncatus), the audibility thresholds were measured for a single pair of equal-amplitude pulses, i.e., clicks, presented to the dolphin in combination with a pulse jam. The pulse jam consisted of pairs of identical pulses with a pulse spacing τj within the pairs and a pair repetition rate f j. Series of pulses were interrupted by a pause R>1/ f j, within which the pulse jam was absent while a pair of test pulses was supplied to one of the two channels at random. Each series had a duration T, and the total stimulation cycle was J= T+ R. The dependence of the test pair detection threshold on the pulse spacing τj was studied at different fixed values of the pulse spacing in the test pair: τt=50, 100, 200, and 500 µs. Preliminary measurements performed with τj=τt=100 µs were used to adjust the parameters of the pulse jam. The threshold shift at τj=τt=100 µs reached 35 dB above the audibility threshold of the test pair in the absence of the pulse jam. On both sides of the point τj=τt=100 µs the thresholds decreased with varying τj to approximately 20 dB above the detection threshold of the test pair in the absence of the jam. However, in the course of training, the threshold curves gradually shifted downwards approaching the detection level of the test pair in the absence of the jam and becoming progressively flatter (the selectivity with respect to the pulse jam vanished). A decrease in the pause duration R restored the dependence of the test pair detection threshold on τj. In this case, a statistically significant maximum was obtained at τj=τt for τj within the critical interval (for τt<500 µs). Beyond the critical interval (for τt>500 µs), even with the smallest pause duration ( R=15 ms), no dependence of the test pair detection thresholds on τj could be observed.

  18. Pair density wave superconducting states and statistical mechanics of dimers

    NASA Astrophysics Data System (ADS)

    Soto Garrido, Rodrigo Andres

    The following thesis is divided in two main parts. Chapters 2, 3 and 4 are devoted to the study of the so called pair-density-wave (PDW) superconducting state and some of its connections to electronic liquid crystal (ELC) phases, its topological aspects in a one dimensional model and its appearance in a quasi-one dimensional system. On the other hand, chapter 5 is focused on the investigation of the classical statistical mechanics properties of dimers, in particular, the dimer model on the Aztec diamond graph and its relation with the octahedron equation. In chapter 2 we present a theory of superconducting states where the Cooper pairs have a nonzero center-of-mass momentum, inhomogeneous superconducting states known as a pair-density-waves (PDWs) states. We show that in a system of spin-1/2 fermions in two dimensions in an electronic nematic spin-triplet phase where rotational symmetry is broken in both real and spin space PDW phases arise naturally in a theory that can be analysed using controlled approximations. We show that several superfluid phases that may arise in this phase can be treated within a controlled BCS mean field theory, with the strength of the spin-triplet nematic order parameter playing the role of the small parameter of this theory. We find that in a spin-triplet nematic phase, in addition to a triplet p-wave and spin-singlet d-wave (or s depending on the nematic phase) uniform superconducting states, it is also possible to have a d-wave (or s) PDW superconductor. The PDW phases found here can be either unidirectional, bidirectional, or tridirectional depending on the spin-triplet nematic phase and which superconducting channel is dominant. In addition, a triple-helix state is found in a particular channel. We show that these PDW phases are present in the weak-coupling limit, in contrast to the usual Fulde-Ferrell-Larkin-Ovchinnikov phases, which require strong coupling physics in addition to a large magnetic field (and often both). In chapter

  19. Three-dimensional nonlinear vibration of gear pairs

    NASA Astrophysics Data System (ADS)

    Eritenel, Tugan; Parker, Robert G.

    2012-07-01

    This work investigates the three-dimensional nonlinear vibration of gear pairs where the nonlinearity is due to portions of gear teeth contact lines losing contact (partial contact loss). The gear contact model tracks partial contact loss using a discretized stiffness network. The nonlinear dynamic response is obtained using the discretized stiffness network, but it is interpreted and discussed with reference to a lumped-parameter gear mesh model named the equivalent stiffness representation. It consists of a translational stiffness acting at a changing center of stiffness location (two parameters) and a twist stiffness. These four parameters, calculated from the dynamic response, change as the gears vibrate, and tracking their behavior as a post-processing tool illuminates the nonlinear gear response. There is a gear mesh twist mode where the twist stiffness is active in addition to the well-known mesh deflection mode where the translational stiffness is active. The twist mode is excited by periodic back and forth axial movement of the center of stiffness in helical gears. The same effect can occur in wide facewidth spur gears if tooth lead modifications or other factors such as shaft and bearing deflections disrupt symmetry about the axial centers of the mating teeth. Resonances of both modes are shown to be nonlinear due to partial and total contact loss. Comparing the numerical results with gear vibration experiments from the literature verifies the model and confirms partial contact loss nonlinearity in experiments.

  20. Pairing and anti-pairing: a balancing act in the diploid genome

    PubMed Central

    Joyce, Eric F.; Erceg, Jelena; Wu, C.-ting

    2016-01-01

    The presence of maternal and paternal homologs appears to be much more than just a doubling of genetic material. We know this because genomes have evolved elaborate mechanisms that permit homologous regions to sense and then respond to each other. One way in which homologs communicate is to come into contact and, in fact, Dipteran insects such as Drosophila excel at this task, aligning all pairs of maternal and paternal chromosomes, end-to-end, in essentially all somatic tissues throughout development. Here, we reexamine the widely held tenet that extensive somatic pairing of homologous sequences cannot occur in mammals and suggest, instead, that pairing may be a widespread and significant potential that has gone unnoticed in mammals because they expend considerable effort to prevent it. We then extend this discussion to interchromosomal interactions, in general, and speculate about the potential of nuclear organization and pairing to impact inheritance. PMID:27065367

  1. Pairing and anti-pairing: a balancing act in the diploid genome.

    PubMed

    Joyce, Eric F; Erceg, Jelena; Wu, C-Ting

    2016-04-01

    The presence of maternal and paternal homologs appears to be much more than just a doubling of genetic material. We know this because genomes have evolved elaborate mechanisms that permit homologous regions to sense and then respond to each other. One way in which homologs communicate is to come into contact and, in fact, Dipteran insects such as Drosophila excel at this task, aligning all pairs of maternal and paternal chromosomes, end-to-end, in essentially all somatic tissues throughout development. Here, we reexamine the widely held tenet that extensive somatic pairing of homologous sequences cannot occur in mammals and suggest, instead, that pairing may be a widespread and significant potential that has gone unnoticed in mammals because they expend considerable effort to prevent it. We then extend this discussion to interchromosomal interactions, in general, and speculate about the potential of nuclear organization and pairing to impact inheritance. PMID:27065367

  2. Long-term fitness consequences of female extra-pair matings in a socially monogamous passerine.

    PubMed

    Schmoll, Tim; Dietrich, Verena; Winkel, Wolfgang; Epplen, Jörg T; Lubjuhn, Thomas

    2003-02-01

    Whether female birds choose extra-pair mating partners to obtain genetic fitness benefits is intensely debated. The most straightforward and crucial test of 'good genes' models of female extra-pair mating is the comparison of naturally 'cross-fostered' maternal half-siblings sharing the same rearing environment as any systematic differences in performance between the two categories of offspring phenotype can be attributed to differential paternal genetic contribution. We analysed local recruitment and first-year reproductive performance of maternal half-siblings in the coal tit (Parus ater), a passerine bird with high levels of extra-pair paternity. We provide a highly comprehensive measure of the long-term fitness consequences of female extra-pair matings based on a large sample of 736 within-pair offspring (WPO) and 368 extra-pair offspring (EPO) from 91 first and 55 second broods, from which 132 breeders recruited into the study population. In contrast to predictions derived from 'good genes' models, we found no differences in local recruitment and seven parameters of first-year reproductive performance when comparing WPO and EPO. These results question the universal validity of findings in other bird species supporting 'good genes' models, particularly as they are based on the best approximation to female fitness obtained so far. PMID:12614574

  3. The Influence of Companion Morphology on Dust Properties and Star Formation in Galaxy Pairs

    NASA Astrophysics Data System (ADS)

    Domingue, Donovan L.; Cao, Chen; Xu, C. Kevin; Jarrett, Tom; Ronca, Joseph; Hill, Emily

    2016-01-01

    We present an analysis of dust properties of a sample of close major-merger galaxy pairs selected by Ks magnitude and redshift. The pairs represent the two populations of spiral-spiral (S+S) and mixed morphology spiral-elliptical (S+E). The CIGALE (Code Investigating GALaxy Emission) is used to fit dust models to the 2MASS, WISE and Herschel flux measurements and derive the parameters describing the PAH contribution, interstellar radiation field (ISRF) and photo-dissociation regions (PDRs). 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.

  4. 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.

  5. Geometrical limitations in grating pair pulse compression

    SciTech Connect

    Brorson, S.D.; Haus, H.A.

    1988-01-01

    Optical-pulse compression using gratings has become a standard technique for producing ultrafast pulses outside a laser cavity. Short pulses produced by a mode-locked laser are focused into an optical fiber. There, self-phase modulation and group velocity dispersion act to broaden the bandwidth of the pulse and impart to it a negative chirp. A pair of diffraction gratings are placed following the fiber. Different frequencies follow different paths through the grating pair; if they are properly oriented, the gratings can compensate for the linear chirp of the pulse. In this way the spectral components of the pulse are compressed in time. The net effect of the system is to produce an output pulse that is shorter than the input pulse because of the additional frequencies generated in the fiber.

  6. 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.

  7. 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

  8. Dissipative solitons in pair-ion plasmas

    SciTech Connect

    Ghosh, Samiran; Adak, Ashish Khan, Manoranjan

    2014-01-15

    The effects of ion-neutral collisions on the dynamics of the nonlinear ion acoustic wave in pair-ion plasma are investigated. The standard perturbative approach leads to a Korteweg-de Vries equation with a linear damping term for the dynamics of the finite amplitude wave. The ion-neutral collision induced dissipation is responsible for the linear damping. The analytical solution and numerical simulation reveal that the nonlinear wave propagates in the form of a weakly dissipative compressive solitons. Furthermore, the width of the soliton is proportional to the amplitude of the wave for fixed soliton velocity. Results are discussed in the context of the fullerene pair-ion plasma experiment.

  9. 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.

  10. 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.

  11. Bosonic topological phase in a paired superfluid

    NASA Astrophysics Data System (ADS)

    Gazit, Snir; Vishwanath, Ashvin

    2016-03-01

    We study an effective model of two interacting species of bosons in two dimensions, which is amenable to sign problem free Monte Carlo simulations. In addition to conventional ground states, we access a paired superfluid which is also a topological phase, protected by the remaining U (1 ) ×Z2 symmetry. This phase arises from the condensation of a composite object, the bound state of vortices and antivortices of one species, to a boson of the second species. We introduce a bulk response function, the Ising analog of the quantized Hall effect, to diagnose the topological phase. The interplay of broken symmetry and topology leads to interesting effects such as fractionally charged vortices in the paired superfluid. Possible extensions towards realistic models of cold atomic bosons are discussed.

  12. Pair Crystallization in the Pseudogap State

    NASA Astrophysics Data System (ADS)

    Chen, Han-Dong; Vafek, Oskar; Yazdani, Ali; Zhang, Shou-Cheng

    2004-03-01

    Recent STM experiments of BiSrCaCuO have shown evidence of real-space organization of electronic states in the pseudogap state[1]. In this talk, we argue based on symmetry considerations as well as model calculations that the experimentally observed ordering is due to organization of d-wave hole pairs into a static lattice, similar to those previously proposed in the vicinity of vortices[2]. In addition to these results, we also make prediction on how to further distinguish between a pair-crystal and more typical electronic modulations due to charge density wave ordering or those due to simple scattering from a periodic potential. [1] M. Vershinin, S. Misra, S. Ono, S. Abe, Y. Ando, and A. Yazdani, submitted. [2] H.D. Chen, J.P. Hu, S. Capponi, E. Arrigoni and S.C. Zhang, Phys. Rev. Lett., 89, 137004 (2002).

  13. Seismic interferometry with antipodal station pairs

    NASA Astrophysics Data System (ADS)

    Lin, Fan-Chi; Tsai, Victor C.

    2013-09-01

    In this study, we analyze continuous data from all Global Seismographic Network stations between year 2000 and 2009 and demonstrate that several body wave phases (e.g., PP, PcPPKP, SKSP, and PPS) propagating between nearly antipodal station pairs can be clearly observed without array stacking using the noise/coda cross-correlation method. Based on temporal correlations with global seismicity, we show that the observed body waves are clearly earthquake related. Moreover, based on single-earthquake analysis, we show that the earthquake coda energy observed between ~10,000 and 30,000 s after a large earthquake contributes the majority of the signal. We refine our method based on these observations and show that the signal can be significantly improved by selecting only earthquake coda times. With our improved processing, the PKIKP phase, which does not benefit from the focusing effect near the antipode, can now also clearly be observed for long-distance station pairs.

  14. Pair importance measures in systems analysis

    SciTech Connect

    Youngblood, R.; Xue, D.; Cho, N.

    1986-01-01

    Importance measures in systems unreliability (or unavailability) analysis provide useful information in identifying components which are critical with regard to the availability or reliability of a system. Various importance measures known in the reliability literature are defined for a single component. This paper extends previous work to define importance measures for a pair of components of the system (accident sequence, core damage frequency, or health risks as appropriate), and illustrates the usefulness of these pairwise importance measures in nuclear power plants. The pairwise importance measures are immediately applicable to risk-based evaluation of the technical specifications; in addition, pairwise importances could play an important role in systems interaction studies by highlighting pairs of events between which a coupling would be significant if it existed.

  15. 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.

  16. Average prime-pair counting formula

    NASA Astrophysics Data System (ADS)

    Korevaar, Jaap; Riele, Herman Te

    2010-04-01

    Taking r>0 , let π_{2r}(x) denote the number of prime pairs (p, p+2r) with p≤ x . The prime-pair conjecture of Hardy and Littlewood (1923) asserts that π_{2r}(x)˜ 2C_{2r} {li}_2(x) with an explicit constant C_{2r}>0 . There seems to be no good conjecture for the remainders ω_{2r}(x)=π_{2r}(x)- 2C_{2r} {li}_2(x) that corresponds to Riemann's formula for π(x)-{li}(x) . However, there is a heuristic approximate formula for averages of the remainders ω_{2r}(x) which is supported by numerical results.

  17. Extra-pair paternity in waved albatrosses.

    PubMed

    Huyvaert, K P; Anderson, D J; Jones, T C; Duan, W; Parker, P G

    2000-09-01

    We estimated the rate of extra-pair fertilizations (EPFs) in waved albatrosses (Phoebastria irrorata) on Isla Española, Galápagos, Ecuador, using multilocus minisatellite DNA fingerprinting. Waved albatrosses are socially monogamous, long-lived seabirds whose main population is on Española. Aggressive extra-pair copulation (EPC) attempts have been observed in the breeding colony during the days preceding egg-laying. Our genetic analyses of 16 families (single chicks and their attending parents) revealed evidence of EPFs in four families. In all cases males were the excluded parent. These data suggest that waved albatrosses have an unusually high rate of EPF relative to taxa with similar life histories. Future behavioural observations will determine the extent to which forced vs. unforced EPCs contribute to this high EPF rate. PMID:10972780

  18. Magnetic instability and pair binding in aromatic hydrocarbon superconductors.

    PubMed

    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 [Formula: see text] 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

  19. Perpendicular propagation of electromagnetic solitons in magnetized thermal pair plasmas

    NASA Astrophysics Data System (ADS)

    Verheest, Frank

    2016-02-01

    The properties of perpendicularly propagating large amplitude electromagnetic solitons are investigated in a thermal, magnetized pair plasma. To obtain a tractable description, these solitons are assumed to be charge neutral and have a linearly polarized magnetic field, and thus represent the nonlinear extension of part of the linear extraordinary mode. From a Sagdeev pseudopotential analysis it transpires that these solitons are compressive and characterized by a wave magnetic field parallel to the static field. The existence domain in compositional parameter space shows pressure-dependent maxima for the soliton velocities, densities and total magnetic field. Physically, an increase in pressure yields a decrease in the acceptable maxima. This is also illustrated on typical pseudopotential and soliton profiles.

  20. NNLL resummation for stop pair-production at the LHC

    NASA Astrophysics Data System (ADS)

    Beenakker, Wim; Borschensky, Christoph; Heger, Raphael; Krämer, Michael; Kulesza, Anna; Laenen, Eric

    2016-05-01

    The production of supersymmetric stop-antistop pairs at the Large Hadron Collider (LHC) is studied including corrections from soft-gluon resummation up to next-to-next-to-leading logarithmic (NNLL) accuracy in the Mellin-space approach. Additionally, corrections to the hard-matching coefficient at one-loop and Coulomb contributions at two-loop order are considered. The NNLL corrections enhance the cross section for all stop masses at centre-of-mass energies of 8 and 13 TeV compared to the previously calculated predictions at next-to-leading logarithmic (NLL) accuracy. Furthermore, a slight increase in the dependence on the additional stop-mixing parameters is observed.

  1. Spectroscopy by frequency-entangled photon pairs

    SciTech Connect

    Yabushita, Atsushi; Kobayashi, Takayoshi

    2004-01-01

    Quantum spectroscopy was performed using the frequency-entangled broadband photon pairs generated by spontaneous parametric down-conversion. An absorptive sample was placed in front of the idler photon detector, and the frequency of signal photons was resolved by a diffraction grating. The absorption spectrum of the sample was measured by counting the coincidences, and the result is in agreement with the one measured by a conventional spectrophotometer with a classical light source.

  2. Modulational instabilities in relativistic pair plasmas

    NASA Astrophysics Data System (ADS)

    Mendonça, J. T.

    2016-05-01

    We study the modulational instability of an intense photon beam in a relativistic pair plasma. We use the wave-kinetic description of the photon field and relativistic fluid equations for electrons and positrons. This allows us to consider the influence of the photon spectral distribution and photon recoil effects on the instability threshold and growth rates. The case of very low frequencies modulations, well below plasma frequency, is compared to that of high-frequency modulations corresponding to the plasmon decay instability.

  3. 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.

  4. 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.

  5. Radio structures in QSO-galaxy pairs

    NASA Technical Reports Server (NTRS)

    Akujor, Chidi E.

    1990-01-01

    It is now generally agreed that if quasars and nearby low redshift galaxies are associated, then there should be luminous connections between them. However, most of the observational evidence being presented is in the optical domain, whereas such evidence should also exist at radio frequencies. The author is, therefore, investigating some quasar-galaxy pairs at radio frequencies to search for luminous connections and other structural peculiarities. Radio maps of some of these sources are presented.

  6. 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.

  7. 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

  8. 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.

  9. 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.

  10. 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

  11. Further Analysis of a Cooper Pair Insulator

    NASA Astrophysics Data System (ADS)

    Hollen, S. M.; Nguyen, H. Q.; Stewart, M. D., Jr.; Shainline, J.; Jin, Aijun; Xu, J. M.; Valles, J. M., Jr.

    2010-03-01

    Amorphous thin films of Bi deposited on a substrate with a Nano-Honeycomb (NHC) array of holes can exhibit a Cooper Pair Insulator (CPI) phase [1]. The transport in this state is dominated by the incoherent tunneling of Cooper Pairs between localized states. The resistivity is activated in temperature, and the magnetoresistance (MR) near the thickness-tuned Superconductor-Insulator Transition (SIT) exhibits a giant peak, as is found in thin films of InOx and TiN. In an effort to learn how the localization of pairs develops, we have investigated films deposited on substrates with different hole radii, order in the hole arrays, and surface roughness. We will present our latest findings on the common features describing the CPI phase, and how the above variations influence its properties and those of the thickness-tuned SIT in these amorphous films. [1] M. D. Stewart Jr., A. Yin, J. M. Xu, and J. M. Valles Jr., Science 318, 1273 (2007).

  12. 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.

  13. Interaction of a skewed Rankine vortex pair

    NASA Astrophysics Data System (ADS)

    Jayavel, S.; Patil, Pratish P.; Tiwari, Shaligram

    2008-08-01

    An analytical investigation is carried out to study the kinematics of a fluid particle in an interacting field of a skewed pair of fixed Rankine vortices. A general formulation governing the kinematics of a fluid particle has been presented based on the superposition of the velocity field due to each vortex in the pair. The kinematics of a Lagrangian fluid particle is found to be governed by a nonlinear dynamical system. The fixed or stationary points of the dynamical system have been identified analytically and their existence is confirmed by the nature of particle paths in the neighborhood of fixed points. The nature of the particle path and velocity signal is reported for general as well as special configurations of the vortex pair in the presence and absence of an external uniform flow. As a specific application of the proposed problem, superimposition of the translational velocity on a semi-infinite field of longitudinal vortices generated by vortex generators mounted on fin plates of heat exchangers has also been studied.

  14. Banach Algebras Associated to Lax Pairs

    NASA Astrophysics Data System (ADS)

    Glazebrook, James F.

    2015-04-01

    Lax pairs featuring in the theory of integrable systems are known to be constructed from a commutative algebra of formal pseudodifferential operators known as the Burchnall- Chaundy algebra. Such pairs induce the well known KP flows on a restricted infinite-dimensional Grassmannian. The latter can be exhibited as a Banach homogeneous space constructed from a Banach *-algebra. It is shown that this commutative algebra of operators generating Lax pairs can be associated with a commutative C*-subalgebra in the C*-norm completion of the *-algebra. In relationship to the Bose-Fermi correspondence and the theory of vertex operators, this C*-algebra has an association with the CAR algebra of operators as represented on Fermionic Fock space by the Gelfand-Naimark-Segal construction. Instrumental is the Plücker embedding of the restricted Grassmannian into the projective space of the associated Hilbert space. The related Baker and tau-functions provide a connection between these two C*-algebras, following which their respective state spaces and Jordan-Lie-Banach algebras structures can be compared.

  15. Pairing Correlations with Single Cooper Pair Transfer to Individual Quantal States

    NASA Astrophysics Data System (ADS)

    Potel, G.; Broglia, R. A.

    2013-01-01

    Making use of the fact that the collective modes associated with the spontaneous (static and dynamic) violation of gauge invariance in atomic nuclei (pairing rotations and pairing vibrations) are amenable to a simple, quite accurate nuclear structure description (BCS and QRPA respectively), it is possible to quantitatively test the reaction mechanism which is at the basis of two-nucleon transfer reactions, specific probe of pairing in nuclei. With the help of the static and dynamic mean field spectroscopic amplitudes, taking into account successive and simultaneous transfer channels properly corrected because of non-orthogonality effects, as well as describing the associated elastic channels in terms of experimentally determined optical potentials, one obtains absolute, two-particle transfer differential cross sections which provide an overall account of the data within experimental errors. One of the first results connected with such quantitative studies of pairing correlations in nuclei is the observation of phonon mediated pairing in the exotic halo nucleus 11Li, and the associated discovery of a new mechanism to break nuclear gauge symmetry: bootstrap, pigmy-resonance-mediated Cooper pair binding.

  16. Hydrostatic pressure study on high temperature superconductors: HgBa(2)Casb(m-1)Cu(m)O(2m+2+delta) (m = 1 to 6) and (Cu,C)Ba(2)Ca(m-1)Cu(m)O(2m+3) (m = 3 and 4)

    NASA Astrophysics Data System (ADS)

    Cao, Yong

    1998-12-01

    Over the last decade, numerous extensive as well as intensive experimental and theoretical investigations have been carried out since the great discovery of high temperature superconductivity (HTSy) in cuprate superconductors Lasb{2-x}Basb{x}CuOsb4,\\ YBasb2Cusb2Osb{7-delta} and other compounds. Although there is still no widely accepted microscopic theory on the mechanism responsible for such high superconducting transition temperatures (Tsb{c}), systematic trends of the evolution of HTSy with various parameters have been studied and analyzed. One of them is the universal inverse parabolic correlation between the Tsb{c} and the number of carriers per CuOsb2 plane (n) in various cuprate superconductors. The high pressure technique provides a clean way to change the distance between atoms without causing the side effects typical of chemical doping, and thus has long been used to test and provide guidance for theoretical models, as well as give hints about the synthesis of compounds with higher Tsb{c}. Therefore, we have done a systematic study on the pressure effect on Tsb{c} of two homologous superconducting compound series: HgBasb2Casb{m-1}Cusb{m}Osb{2m+2+delta} (Hg-12(m-1)m) (m = 1 to 6) and (Cu,C)Basb2Casb{m-1}Cusb{m}Osb{2m+3+delta} ((Cu,C)-12(m-1)m) (m = 3 and 4). Several factors which influence the hydrostatic pressure effect on Tsb{c} have been systematically analyzed. They include the n, the type of charge reservoir layer, and the number of CuOsb2 layers per unit cell (m). We came to several conclusion: (1) The inverse parabolic Tsb{c}(n) correlation and its universal parameters are valid only under conditions more restrictive than originally expected, and the rigid band model may not hold for some cuprate superconductors under pressure. (2) The pressure coefficient (dTsb{c}/dP) may have a different dependence on n. The compounds with Cu-O chains in their charge reservoir usually show a large linear variation of dTsb{c}/dP with n, while no significant

  17. Overexpression of AtAP1M3 regulates flowering time and floral development in Arabidopsis and effects key flowering-related genes in poplar.

    PubMed

    Chen, Zhong; Ye, Meixia; Su, Xiaoxing; Liao, Weihua; Ma, Huandi; Gao, Kai; Lei, Bingqi; An, Xinmin

    2015-08-01

    APETALA1 plays a crucial role in the transition from vegetative to reproductive phase and in floral development. In this study, to determine the effect of AP1 expression on flowering time and floral organ development, transgenic Arabidopsis and poplar overexpressing of AtAP1M3 (Arabidopsis AP1 mutant by dominant negative mutation) were generated. Transgenic Arabidopsis with e35Spro::AtAP1M3 displayed phenotypes with delayed-flowering compared to wild-type and flowers with abnormal sepals, petals and stamens. In addition, transgenic Arabidopsis plants exhibited reduced growth vigor compared to the wild-type plants. Ectopic expression of AtAP1M3 in poplar resulted in up- or down-regulation of some endogenous key flowering-related genes, including floral meristems identity gene LFY, B-class floral organ identity genes AP3 and PI, flowering pathway integrator FT1 and flower repressors TFL1 and SVP. These results suggest that AtAP1M3 regulates flowering time and floral development in plants. PMID:25820621

  18. M3D (Media 3D): a new programming language for web-based virtual reality in E-Learning and Edutainment

    NASA Astrophysics Data System (ADS)

    Chakaveh, Sepideh; Skaley, Detlef; Laine, Patricia; Haeger, Ralf; Maad, Soha

    2003-01-01

    Today, interactive multimedia educational systems are well established, as they prove useful instruments to enhance one's learning capabilities. Hitherto, the main difficulty with almost all E-Learning systems was latent in the rich media implementation techniques. This meant that each and every system should be created individually as reapplying the media, be it only a part, or the whole content was not directly possible, as everything must be applied mechanically i.e. by hand. Consequently making E-learning systems exceedingly expensive to generate, both in time and money terms. Media-3D or M3D is a new platform independent programming language, developed at the Fraunhofer Institute Media Communication to enable visualisation and simulation of E-Learning multimedia content. M3D is an XML-based language, which is capable of distinguishing between the3D models from that of the 3D scenes, as well as handling provisions for animations, within the programme. Here we give a technical account of M3D programming language and briefly describe two specific application scenarios where M3D is applied to create virtual reality E-Learning content for training of technical personnel.

  19. 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

  20. 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