Sample records for anomalous process behaviour

  1. Fractional Stochastic Field Theory

    NASA Astrophysics Data System (ADS)

    Honkonen, Juha

    2018-02-01

    Models describing evolution of physical, chemical, biological, social and financial processes are often formulated as differential equations with the understanding that they are large-scale equations for averages of quantities describing intrinsically random processes. Explicit account of randomness may lead to significant changes in the asymptotic behaviour (anomalous scaling) in such models especially in low spatial dimensions, which in many cases may be captured with the use of the renormalization group. Anomalous scaling and memory effects may also be introduced with the use of fractional derivatives and fractional noise. Construction of renormalized stochastic field theory with fractional derivatives and fractional noise in the underlying stochastic differential equations and master equations and the interplay between fluctuation-induced and built-in anomalous scaling behaviour is reviewed and discussed.

  2. The use of self-organising maps for anomalous behaviour detection in a digital investigation.

    PubMed

    Fei, B K L; Eloff, J H P; Olivier, M S; Venter, H S

    2006-10-16

    The dramatic increase in crime relating to the Internet and computers has caused a growing need for digital forensics. Digital forensic tools have been developed to assist investigators in conducting a proper investigation into digital crimes. In general, the bulk of the digital forensic tools available on the market permit investigators to analyse data that has been gathered from a computer system. However, current state-of-the-art digital forensic tools simply cannot handle large volumes of data in an efficient manner. With the advent of the Internet, many employees have been given access to new and more interesting possibilities via their desktop. Consequently, excessive Internet usage for non-job purposes and even blatant misuse of the Internet have become a problem in many organisations. Since storage media are steadily growing in size, the process of analysing multiple computer systems during a digital investigation can easily consume an enormous amount of time. Identifying a single suspicious computer from a set of candidates can therefore reduce human processing time and monetary costs involved in gathering evidence. The focus of this paper is to demonstrate how, in a digital investigation, digital forensic tools and the self-organising map (SOM)--an unsupervised neural network model--can aid investigators to determine anomalous behaviours (or activities) among employees (or computer systems) in a far more efficient manner. By analysing the different SOMs (one for each computer system), anomalous behaviours are identified and investigators are assisted to conduct the analysis more efficiently. The paper will demonstrate how the easy visualisation of the SOM enhances the ability of the investigators to interpret and explore the data generated by digital forensic tools so as to determine anomalous behaviours.

  3. Cusping, transport and variance of solutions to generalized Fokker-Planck equations

    NASA Astrophysics Data System (ADS)

    Carnaffan, Sean; Kawai, Reiichiro

    2017-06-01

    We study properties of solutions to generalized Fokker-Planck equations through the lens of the probability density functions of anomalous diffusion processes. In particular, we examine solutions in terms of their cusping, travelling wave behaviours, and variance, within the framework of stochastic representations of generalized Fokker-Planck equations. We give our analysis in the cases of anomalous diffusion driven by the inverses of the stable, tempered stable and gamma subordinators, demonstrating the impact of changing the distribution of waiting times in the underlying anomalous diffusion model. We also analyse the cases where the underlying anomalous diffusion contains a Lévy jump component in the parent process, and when a diffusion process is time changed by an uninverted Lévy subordinator. On the whole, we present a combination of four criteria which serve as a theoretical basis for model selection, statistical inference and predictions for physical experiments on anomalously diffusing systems. We discuss possible applications in physical experiments, including, with reference to specific examples, the potential for model misclassification and how combinations of our four criteria may be used to overcome this issue.

  4. Anomalous diffusion of single metal atoms on a graphene oxide support

    DOE PAGES

    Furnival, Tom; Leary, Rowan K.; Tyo, Eric C.; ...

    2017-04-21

    Recent studies of single-atom catalysts open up the prospect of designing exceptionally active and environmentally efficient chemical processes. The stability and durability of such catalysts is governed by the strength with which the atoms are bound to their support and their diffusive behaviour. Here we use aberration-corrected STEM to image the diffusion of single copper adatoms on graphene oxide. As a result, we discover that individual atoms exhibit anomalous diffusion as a result of spatial and energetic disorder inherent in the support, and interpret the origins of this behaviour to develop a physical picture for the surface diffusion of singlemore » metal atoms.« less

  5. Identifying Anomalous Behaviour in AIS Data: Loitering and Gaps in Transmission as Indicators of IUU Associated Behaviour.

    NASA Astrophysics Data System (ADS)

    Ford, J.; Peel, D.; Wilcox, C.; Kroodsma, D.

    2016-12-01

    Identifying anomalous behaviour associated with Illegal, Unreported and Unregulated (IUU) fishing including supportive activities such as transshipment, is a key step to combating IUU fishing. We use spatial statistical models and Automatic Identification System (AIS) data to identify anomalous activity, specifically various indicators of loitering behaviours (for example, vessels travelling slower than expected, perhaps rendezvousing for transshipment), and gaps in AIS transmissions. Gaps occur for three basic reasons: saturation of the system in locations with high vessel density; poor quality transmissions due to equipment on the vessel or receiver; and intentional disabling of AIS transmitters. Resolving which of these mechanisms is generating gaps in transmissions from a given vessel is a critical task in using AIS to monitor vessels. Moreover, separating saturation and equipment issues from intentional disabling is a useful task in risk identification of IUU associated behaviour. Using this information on loitering behaviour and gaps in transmission, we identify and rank vessels which appear to be acting anomalously, with a focus on identifying potential IUU related activities. This information, combined with other sources of data, could help support enforcement agencies to implement international strategies such as the Port State Measures Agreement. A global list of such vessels and historical evidence of anomalous behaviour, would increase local powers of protection and provide one more step toward transparency within global fisheries.

  6. Grain boundary-dominated electrical conduction and anomalous optical-phonon behaviour near the Neel temperature in YFeO3 ceramics

    NASA Astrophysics Data System (ADS)

    Raut, Subhajit; Babu, P. D.; Sharma, R. K.; Pattanayak, Ranjit; Panigrahi, Simanchalo

    2018-05-01

    We investigated the anomalous behaviour in the dielectric properties, occurring nearly at room temperature and at elevated temperatures (near the Neel temperature TN) of the polycrystalline samples of YFeO3 (YFO) ceramics. On the prepared YFO ceramics, the magnetic measurements showed the Neel temperature of YFO to be 650 K, below which the compound exhibited the weak ferromagnetic behaviour. X-ray photoelectron spectroscopy (XPS) shows the presence of Fe ions (Fe2+ and Fe3+ states) and also revealed the formation of the oxygen vacancies. The frequency dependence of the complex dielectric constant within the frequency domain of 100 Hz-1 MHz shows the presence of grain dominated dielectric relaxation over the thermal window of 300-373 K. The activation energy Eact.ɛ=0.611 eV extracted from the imaginary permittivity spectrum indicates the involvement of oxygen vacancies in the relaxation process. Above 493 K, the ac conductivity, complex impedance, and modulus studies revealed appreciable conduction and relaxation processes occurring in YFO ceramics with respective activation energies Eac t . σ=1.362 eV and Eac t . Z=1.345 eV , which suggests that the oxygen vacancies are also involved for the anomalous behaviour of the dielectric constant at elevated temperatures. The temperature dependent Raman spectroscopic measurements within the thermal window of 298-698 K showed anomalous variations of the line widths and frequencies of several Raman active modes above 473 K up to the vicinity of TN pointing towards the presence of admixtures of the electron-phonon and spin-phonon coupling in the system. A further study on the thermal variation of the B2g(4) mode frequency with [M(T)/MS]2 shows the occurrence of strong spin-phonon (s-p) coupling, while the line shape shows the presence of the Fano asymmetry, suggesting spin dependent electron-phonon (e-p) coupling in the system below TN.

  7. Balloons Revisited

    ERIC Educational Resources Information Center

    Jeskova, Z.; Featonby, D.; Fekova, V.

    2012-01-01

    Whilst everyone is familiar with the process of blowing up a balloon, few of us have gone further to quantify the actual pressures involved at different stages in the inflation process. This paper seeks to describe experiments to fill some of those gaps and examine some of the apparently anomalous behaviour of connected balloons. (Contains 12…

  8. Underdamped scaled Brownian motion: (non-)existence of the overdamped limit in anomalous diffusion.

    PubMed

    Bodrova, Anna S; Chechkin, Aleksei V; Cherstvy, Andrey G; Safdari, Hadiseh; Sokolov, Igor M; Metzler, Ralf

    2016-07-27

    It is quite generally assumed that the overdamped Langevin equation provides a quantitative description of the dynamics of a classical Brownian particle in the long time limit. We establish and investigate a paradigm anomalous diffusion process governed by an underdamped Langevin equation with an explicit time dependence of the system temperature and thus the diffusion and damping coefficients. We show that for this underdamped scaled Brownian motion (UDSBM) the overdamped limit fails to describe the long time behaviour of the system and may practically even not exist at all for a certain range of the parameter values. Thus persistent inertial effects play a non-negligible role even at significantly long times. From this study a general questions on the applicability of the overdamped limit to describe the long time motion of an anomalously diffusing particle arises, with profound consequences for the relevance of overdamped anomalous diffusion models. We elucidate our results in view of analytical and simulations results for the anomalous diffusion of particles in free cooling granular gases.

  9. Underdamped scaled Brownian motion: (non-)existence of the overdamped limit in anomalous diffusion

    PubMed Central

    Bodrova, Anna S.; Chechkin, Aleksei V.; Cherstvy, Andrey G.; Safdari, Hadiseh; Sokolov, Igor M.; Metzler, Ralf

    2016-01-01

    It is quite generally assumed that the overdamped Langevin equation provides a quantitative description of the dynamics of a classical Brownian particle in the long time limit. We establish and investigate a paradigm anomalous diffusion process governed by an underdamped Langevin equation with an explicit time dependence of the system temperature and thus the diffusion and damping coefficients. We show that for this underdamped scaled Brownian motion (UDSBM) the overdamped limit fails to describe the long time behaviour of the system and may practically even not exist at all for a certain range of the parameter values. Thus persistent inertial effects play a non-negligible role even at significantly long times. From this study a general questions on the applicability of the overdamped limit to describe the long time motion of an anomalously diffusing particle arises, with profound consequences for the relevance of overdamped anomalous diffusion models. We elucidate our results in view of analytical and simulations results for the anomalous diffusion of particles in free cooling granular gases. PMID:27462008

  10. Numerical study of anomalous dynamic scaling behaviour of (1+1)-dimensional Das Sarma-Tamborenea model

    NASA Astrophysics Data System (ADS)

    Xun, Zhi-Peng; Tang, Gang; Han, Kui; Hao, Da-Peng; Xia, Hui; Zhou, Wei; Yang, Xi-Quan; Wen, Rong-Ji; Chen, Yu-Ling

    2010-07-01

    In order to discuss the finite-size effect and the anomalous dynamic scaling behaviour of Das Sarma-Tamborenea growth model, the (1+1)-dimensional Das Sarma-Tamborenea model is simulated on a large length scale by using the kinetic Monte-Carlo method. In the simulation, noise reduction technique is used in order to eliminate the crossover effect. Our results show that due to the existence of the finite-size effect, the effective global roughness exponent of the (1+1)-dimensional Das Sarma-Tamborenea model systematically decreases with system size L increasing when L > 256. This finding proves the conjecture by Aarao Reis[Aarao Reis F D A 2004 Phys. Rev. E 70 031607]. In addition, our simulation results also show that the Das Sarma-Tamborenea model in 1+1 dimensions indeed exhibits intrinsic anomalous scaling behaviour.

  11. A dynamic Monte Carlo study of anomalous current voltage behaviour in organic solar cells

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Feron, K., E-mail: Krishna.Feron@csiro.au; Fell, C. J.; CSIRO Energy Flagship, Newcastle, NSW 2300

    2014-12-07

    We present a dynamic Monte Carlo (DMC) study of s-shaped current-voltage (I-V) behaviour in organic solar cells. This anomalous behaviour causes a substantial decrease in fill factor and thus power conversion efficiency. We show that this s-shaped behaviour is induced by charge traps that are located at the electrode interface rather than in the bulk of the active layer, and that the anomaly becomes more pronounced with increasing trap depth or density. Furthermore, the s-shape anomaly is correlated with interface recombination, but not bulk recombination, thus highlighting the importance of controlling the electrode interface. While thermal annealing is known tomore » remove the s-shape anomaly, the reason has been not clear, since these treatments induce multiple simultaneous changes to the organic solar cell structure. The DMC modelling indicates that it is the removal of aluminium clusters at the electrode, which act as charge traps, that removes the anomalous I-V behaviour. Finally, this work shows that the s-shape becomes less pronounced with increasing electron-hole recombination rate; suggesting that efficient organic photovoltaic material systems are more susceptible to these electrode interface effects.« less

  12. Multifrequency behaviour of the anomalous events of PSR J0922+0638

    NASA Astrophysics Data System (ADS)

    Shaifullah, G.; Tiburzi, C.; Osłowski, S.; Verbiest, J. P. W.; Szary, A.; Künsemöller, J.; Horneffer, A.; Anderson, J.; Kramer, M.; Schwarz, D. J.; Mann, G.; Steinmetz, M.; Vocks, C.

    2018-06-01

    PSR J0922+0638 (B0919+06) shows unexplained anomalous variations in the on-pulse phase, where the pulse appears to episodically move to an earlier longitude for a few tens of rotations before reverting to the usual phase for approximately several hundred to more than a thousand rotations. These events, where the pulse moves in phase by up to 5°, have been previously detected in observations from ˜300 to 2000 MHz. We present simultaneous observations from the Effelsberg 100-m radio telescope at 1350 MHz and the Bornim (Potsdam) station of the LOw Frequency ARray at 150 MHz. Our observations present the first evidence for an absence of the anomalous phase-shifting behaviour at 150 MHz. Instead, the observed intensity at the usual pulse-phase typically decreases, often showing a pseudo-nulling feature corresponding to the times when phase shifts are observed at 1350 MHz. The presence of weak emission at the usual pulse-phase supports the theory that these shifts may result from processes similar to the `profile-absorption' expected to operate for PSR J0814+7429 (B0809+74). A possible mechanism for this could be intrinsic variations of the emission within the pulsar's beam combined with absorption by expanding shells of electrons in the line of sight.

  13. Anomalous dynamics of intruders in a crowded environment of mobile obstacles

    PubMed Central

    Sentjabrskaja, Tatjana; Zaccarelli, Emanuela; De Michele, Cristiano; Sciortino, Francesco; Tartaglia, Piero; Voigtmann, Thomas; Egelhaaf, Stefan U.; Laurati, Marco

    2016-01-01

    Many natural and industrial processes rely on constrained transport, such as proteins moving through cells, particles confined in nanocomposite materials or gels, individuals in highly dense collectives and vehicular traffic conditions. These are examples of motion through crowded environments, in which the host matrix may retain some glass-like dynamics. Here we investigate constrained transport in a colloidal model system, in which dilute small spheres move in a slowly rearranging, glassy matrix of large spheres. Using confocal differential dynamic microscopy and simulations, here we discover a critical size asymmetry, at which anomalous collective transport of the small particles appears, manifested as a logarithmic decay of the density autocorrelation functions. We demonstrate that the matrix mobility is central for the observed anomalous behaviour. These results, crucially depending on size-induced dynamic asymmetry, are of relevance for a wide range of phenomena ranging from glassy systems to cell biology. PMID:27041068

  14. Anomalous vibrational modes in acetanilide as studied by inelastic neutron scattering

    NASA Astrophysics Data System (ADS)

    Barthes, Mariette; Eckert, Juegen; Johnson, Susanna W.; Moret, Jacques; Swanson, Basil I.; Unkefer, Clifford J.

    1992-10-01

    A study of the anomalous modes in acetanilide and five deuterated derivatives by incoherent inelastic neutron scattering is reported. These data show that the dynamics of the amide and methyl groups influence each other. In addition, the anomalous temperature behaviour of the NH out-of-plane bending mode is confirmed. These observations suggest that the self-trapping mechanism in ACN may be more complex than hitherto assumed.

  15. Anomalous behaviour of magnetic coercivity in graphene oxide and reduced graphene oxide

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bagani, K.; Bhattacharya, A.; Kaur, J.

    In this report, we present the temperature dependence of the magnetic coercivity of graphene oxide (GO) and reduced graphene oxide (RGO). We observe an anomalous decrease in coercivity of GO and RGO with decreasing temperature. The observation could be understood by invoking the inherent presence of wrinkles on graphene oxide due to presence of oxygen containing groups. Scanning electron microscopic image reveals high wrinkles in GO than RGO. We observe higher coercivity in RGO than in GO. At room temperature, we observe antiferromagnetic and ferromagnetic behaviours in GO and RGO, respectively. Whereas, at low temperatures (below T = 60–70 K), both materials showmore » paramagnetic behaviour.« less

  16. Adults with autism spectrum conditions experience increased levels of anomalous perception.

    PubMed

    Milne, Elizabeth; Dickinson, Abigail; Smith, Richard

    2017-01-01

    Autism spectrum condition (ASC) is characterised by differences in social interaction and behavioural inflexibility. In addition to these core symptoms, atypical sensory responses are prevalent in the ASC phenotype. Here we investigated anomalous perception, i.e. hallucinatory and/or out of body experiences in adults with ASC. Thirty participants with an ASC diagnosis and thirty neurotypical controls completed the Cardiff Anomalous Perception Scale (CAPS) and the Social Responsiveness Scale (SRS-2). The CAPS is a 32-item questionnaire that asks participants to indicate whether or not they experience a range of anomalous and out of body experiences, and to rate how intrusive and distressing these experiences are. The SRS-2 asks participants to rate the extent to which they identify with a series of 65 statements that describe behaviours associated with the autism phenotype. We found that total CAPS score was significantly higher in the participants with ASC (mean = 14.8, S.D. = 7.9) than the participants without ASC (mean = 3.6, S.D. = 4.1). In addition, the frequency of anomalous perception, the level of distraction and the level of distress associated with the experience were significantly increased in participants with ASC. Importantly, both the frequency of anomalous perceptual experiences and the level of distress caused by anomalous perception in this sample of adults with ASC were very similar to that reported previously in a sample of non-autistic participants who were being treated in hospital for a current psychotic episode. These data indicate that anomalous perceptual experiences are common in adults with ASC and are associated with a high level of distress. The origins of anomalous perception in ASC and the implication of this phenomenon are considered.

  17. Observation of anomalous Hall effect in a non-magnetic two-dimensional electron system

    PubMed Central

    Maryenko, D.; Mishchenko, A. S.; Bahramy, M. S.; Ernst, A.; Falson, J.; Kozuka, Y.; Tsukazaki, A.; Nagaosa, N.; Kawasaki, M.

    2017-01-01

    Anomalous Hall effect, a manifestation of Hall effect occurring in systems without time-reversal symmetry, has been mostly observed in ferromagnetically ordered materials. However, its realization in high-mobility two-dimensional electron system remains elusive, as the incorporation of magnetic moments deteriorates the device performance compared to non-doped structure. Here we observe systematic emergence of anomalous Hall effect in various MgZnO/ZnO heterostructures that exhibit quantum Hall effect. At low temperatures, our nominally non-magnetic heterostructures display an anomalous Hall effect response similar to that of a clean ferromagnetic metal, while keeping a large anomalous Hall effect angle θAHE≈20°. Such a behaviour is consistent with Giovannini–Kondo model in which the anomalous Hall effect arises from the skew scattering of electrons by localized paramagnetic centres. Our study unveils a new aspect of many-body interactions in two-dimensional electron systems and shows how the anomalous Hall effect can emerge in a non-magnetic system. PMID:28300133

  18. How Physicists Made Stable Lévy Processes Physically Plausible

    NASA Astrophysics Data System (ADS)

    Schinckus, Christophe

    2013-08-01

    Stable Lévy processes have very interesting properties for describing the complex behaviour of non-equilibrium dissipative systems such as turbulence, anomalous diffusion or financial markets. However, although these processes better fit the empirical data, some of their statistical properties can raise several theoretical problems in empirical applications because they generate infinite variables. Econophysicists have developed statistical solutions to make these processes physically plausible. This paper presents a review of these analytical solutions (truncations) for stable Lévy processes and how econophysicists transformed them into data-driven processes. The evolution of these analytical solutions is presented as a progressive research programme provided by (econo)physicists for theoretical problems encountered in financial economics in the 1960s and the 1970s.

  19. Anomalous volatility scaling in high frequency financial data

    NASA Astrophysics Data System (ADS)

    Nava, Noemi; Di Matteo, T.; Aste, Tomaso

    2016-04-01

    Volatility of intra-day stock market indices computed at various time horizons exhibits a scaling behaviour that differs from what would be expected from fractional Brownian motion (fBm). We investigate this anomalous scaling by using empirical mode decomposition (EMD), a method which separates time series into a set of cyclical components at different time-scales. By applying the EMD to fBm, we retrieve a scaling law that relates the variance of the components to a power law of the oscillating period. In contrast, when analysing 22 different stock market indices, we observe deviations from the fBm and Brownian motion scaling behaviour. We discuss and quantify these deviations, associating them to the characteristics of financial markets, with larger deviations corresponding to less developed markets.

  20. Multiwavelength Photometric and Spectropolarimetric Analysis of the FSRQ 3C 279

    NASA Astrophysics Data System (ADS)

    Patiño-Álvarez, V. M.; Fernandes, S.; Chavushyan, V.; López-Rodríguez, E.; León-Tavares, J.; Schlegel, E. M.; Carrasco, L.; Valdés, J.; Carramiñana, A.

    2018-06-01

    In this paper, we present light curves for 3C 279 over a time period of six years; from 2008 to 2014. Our multiwavelength data comprise 1 mm to gamma-rays, with additional optical polarimetry. Based on the behaviour of the gamma-ray light curve with respect to other bands, we identified three different activity periods. One of the activity periods shows anomalous behaviour with no gamma-ray counterpart associated with optical and NIR flares. Another anomalous activity period shows a flare in gamma-rays, 1 mm and polarization degree, however, it does not have counterparts in the UV continuum, optical and NIR bands. We find a significant overall correlation of the UV continuum emission, the optical and NIR bands. This correlation suggests that the NIR to UV continuum is co-spatial. We also find a correlation between the UV continuum and the 1 mm data, which implies that the dominant process in producing the UV continuum is synchrotron emission. The gamma-ray spectral index shows statistically significant variability and an anti-correlation with the gamma-ray luminosity. We demonstrate that the dominant gamma-ray emission mechanism in 3C 279 changes over time. Alternatively, the location of the gamma-ray emission zone itself may change depending on the activity state of the central engine.

  1. Layer-dependent quantum cooperation of electron and hole states in the anomalous semimetal WTe 2

    DOE PAGES

    Das, Pranab Kumar; Di Sante, D.; Vobornik, I.; ...

    2016-02-29

    The behaviour of electrons and holes in a crystal lattice is a fundamental quantum phenomenon, accounting for a rich variety of material properties. Boosted by the remarkable electronic and physical properties of two-dimensional materials such as graphene and topological insulators, transition metal dichalcogenides have recently received renewed attention. In this context, the anomalous bulk properties of semimetallic WTe 2 have attracted considerable interest. We report angle- and spin-resolved photoemission spectroscopy of WTe 2 single crystals, through which we disentangle the role of W and Te atoms in the formation of the band structure and identify the interplay of charge, spinmore » and orbital degrees of freedom. Supported by first-principles calculations and high-resolution surface topography, we also reveal the existence of a layer-dependent behaviour. The balance of electron and hole states is found only when considering at least three Te–W–Te layers, showing that the behaviour of WTe 2 is not strictly two dimensional.« less

  2. The anomalous demagnetization behaviour of chondritic meteorites

    NASA Astrophysics Data System (ADS)

    Morden, S. J.

    1992-06-01

    Alternating field (AF) demagnetization of chondritic samples often shows anomalous results such as large directional and intensity changes; 'saw-tooth' intensity vs. demagnetizing field curves are also prevalent. An attempt to explain this behaviour is presented, using a computer model in which individual 'mineral grains' can be 'magnetized' in a variety of different ways. A simulated demagnetization can then be carried out to examine the results. It was found that the experimental behaviour of chondrites can be successfully mimicked by loading the computer model with a series of randomly orientated and sized vectors. The parameters of the model can be changed to reflect different trends seen in experimental data. Many published results can be modelled using this method. A known magnetic mineralogy can be modelled, and an unknown mineralogy deduced from AF demagnetization curves. Only by comparing data from mutually orientated samples can true stable regions for palaeointensity measurements be identified, calling into question some previous estimates of field strength from meteorites.

  3. The origin of anomalous transport in porous media - is it possible to make a priori predictions?

    NASA Astrophysics Data System (ADS)

    Bijeljic, Branko; Blunt, Martin

    2013-04-01

    Despite the range of significant applications of flow and solute transport in porous rock, including contaminant migration in subsurface hydrology, geological storage of carbon-dioxide and tracer studies and miscible displacement in oil recovery, even the qualitative behavior in the subsurface is uncertain. The non-Fickian nature of dispersive processes in heterogeneous porous media has been demonstrated experimentally from pore to field scales. However, the exact relationship between structure, velocity field and transport has not been fully understood. Advances in X ray imaging techniques made it possible to accurately describe structure of the pore space, helping predict flow and anomalous transport behaviour using direct simulation. This is demonstrated by simulating solute transport through 3D images of rock samples, with resolutions of a few microns, representing geological media of increasing pore-scale complexity: a sandpack, a sandstone, and a carbonate. A novel methodology is developed that predicts solute transport at the pore scale by using probability density functions of displacement (propagators) and probability density function of transit time between the image voxels, and relates it to probability density function of normalized local velocity. A key advantage is that full information on velocity and solute concentration is retained in the models. The methodology includes solving for Stokes flow by Open Foam, solving for advective transport by the novel streamline simulation method, and superimposing diffusive transport diffusion by the random walk method. It is shown how computed propagators for beadpack, sandstone and carbonate depend on the spread in the velocity distribution. A narrow velocity distribution in the beadpack leads to the least anomalous behaviour where the propagators rapidly become Gaussian; the wider velocity distribution in the sandstone gives rise to a small immobile concentration peak, and a large secondary mobile peak moving at approximately the average flow speed; in the carbonate with the widest velocity distribution the stagnant concentration peak is persistent, while the emergence of a smaller secondary mobile peak is observed, leading to a highly anomalous behavior. This defines different generic nature of non-Fickian transport in the three media and quantifies the effect of pore structure on transport. Moreover, the propagators obtained by the model are in a very good agreement with the propagators measured on beadpack, Bentheimer sandstone and Portland carbonate cores in nuclear magnetic resonance experiments. These findings demonstrate that it is possible to make a priori predictions of anomalous transport in porous media. The importance of these findings for transport in complex carbonate rock micro-CT images is discussed, classifying them in terms of degree of anomalous transport that can have an impact at the field scale. Extensions to reactive transport will be discussed.

  4. Observation of the thermal influenced quantum behaviour of water near a solid interface.

    PubMed

    Yoon, Hongkee; Yoon, Byoung Jip

    2018-05-03

    Water is essential for life. However, the structure and properties of water are still not well understood. It has been introduced that anomalies are in vicinal water near solid interfaces. We performed capillary flow experiments on water with a silica colloid sample using a high-performance liquid chromatography (HPLC) system by accurately varying the temperature and analysed the peak shape rigorously. We obtained a novel anomalous temperature spectrum from the peak-shape analysis. Here we report the observed distinct specific anomalous temperature (SAT) behaviour in vicinal water at silica interface. The anomaly appeared in the viscous force that was derived from a relationship between the shape of the HPLC peak and the velocity profile for the capillary flow. The observations were highly reproducible, and we conclude that the SAT is related to the quantum mechanical behaviour of water, in agreement of the characteristic acceptance of thermal displacement according to the Franck-Condon principle. We performed the same experiments using heavy water and water mixed with a small amount of methanol, and the results support the quantum phenomenological origin.

  5. "Anomalous" excitation in hydrogen-bonded molecular crystals - a Raman scattering study of specifically deuterated acetanilide (C 6D 5-CONH-CD 3)

    NASA Astrophysics Data System (ADS)

    Sauvajol, J. L.; De Nunzio, G.; Almairac, R.; Moret, J.; Barthés, M.; Bataillon, Place E.

    1991-01-01

    The focus of experimental and theoretical works about crystalline Acetanilide has been the "anomalous" temperature-dependent ir absorption and Raman peaks at about 1650 cm -1 and the multiband structure in the N-H stretch region. A lively discussion about the assignment of these "anomalous" bands has arisen and is still in progress. The present Raman experiments should be placed in this context as an attempt to identify the molecular degrees of freedom which originate the "anomalous" bands. In this aim Raman experiments have been performed on specifically deuterated Acetanilide [C 6D 5-CONH-CD 3] single crystal in the low-frequency (phonon) and C=O stretching regions. On cooling a distinct band at about 1495 cm -1 increases in intensity. We assign this peak to the equivalent of the 1650 cm -1 band in Acetanilide. The temperature dependence of this Raman line was studied. The results are discussed in the light of the models proposed to explain the anomalous behaviour of the 1650 cm -1 Raman line in Acetanilide.

  6. Disorder dependence electron phonon scattering rate of V82Pd18 - xFex alloys at low temperature

    NASA Astrophysics Data System (ADS)

    Jana, R. N.; Meikap, A. K.

    2018-04-01

    We have systematically investigated the disorder dependence electron phonon scattering rate in three dimensional disordered V82Pd18 - xFex alloys. A minimum in temperature dependence resistivity curve has been observed at low temperature T =Tm. In the temperature range 5 K ≤ T ≤Tm the resistivity correction follows ρo 5 / 2T 1 / 2 law. The dephasing scattering time has been calculated from analysis of magnetoresistivity by weak localization theory. The electron dephasing time is dominated by electron-phonon scattering and follows anomalous temperature (T) and disorder (ρ0) dependence behaviour like τe-ph-1 ∝T2 /ρ0, where ρ0 is the impurity resistivity. The magnitude of the saturated dephasing scattering time (τ0) at zero temperature decreases with increasing disorder of the samples. Such anomalous behaviour of dephasing scattering rate is still unresolved.

  7. STUDIES ON THE ANOMALOUS VISCOSITY AND FLOW-BIREFRINGENCE OF PROTEIN SOLUTIONS

    PubMed Central

    Lawrence, A. S. C.; Needham, Joseph; Shen, Shih-Chang

    1944-01-01

    1. A coaxial viscosimeter which permits the simultaneous determination of relative and anomalous viscosity and of flow-birefringence is described. Flow-anomaly and flow-birefringence are regarded as characteristic of elongated micelles and molecules. 2. Such methods have been applied to dilute solutions of proteins. The conditions under which the coaxial (Couette) viscosimeter measures the viscosity of the bulk phase and the surface film phase respectively have been investigated and are described. 3. The general behaviour of protein solutions subjected to shear is summarised. PMID:19873384

  8. Identification of anomalous motion of thunderstorms using daily rainfall fields

    NASA Astrophysics Data System (ADS)

    del Moral, Anna; Llasat, Maria Carmen; Rigo, Tomeu

    2016-04-01

    Adverse weather phenomena in Catalonia (NE of the Iberian Peninsula) is commonly associated to heavy rains, large hail, strong winds, and/or tornados, all of them caused by thunderstorms. In most of the cases with adverse weather, thunderstorms vary sharply their trajectories in a concrete moment, changing completely the motion directions that have previously followed. Furthermore, it is possible that a breaking into several cells may be produced, or, in the opposite, it can be observed a joining of different thunderstorms into a bigger system. In order to identify the main features of the developing process of thunderstorms and the anomalous motions that these may follow in some cases, this contribution presents a classification of the events using daily rainfall fields, with the purpose of distinguishing quickly anomalous motion of thunderstorms. The methodology implemented allows classifying the daily rainfall fields in three categories by applying some thresholds related with the daily precipitation accumulated values and their extension: days with "no rain", days with "potentially convective" rain and days with "non-potentially convective" rain. Finally, for those "potentially convective" daily rainfall charts, it also allows a geometrical identification and classification of all the convective structures into "ellipse" and "non-ellipse", obtaining then the structures with "normal" or "anomalous" motion pattern, respectively. The work is focused on the period 2008-2015, and presents some characteristics of the rainfall behaviour in terms of the seasonal distribution of convective rainfall or the geographic variability. It shows that convective structures are mainly found during late spring and summer, even though they can be recorded in any time of the year. Consequently, the maximum number of convective structures with anomalous motion is recorded between July and November. Furthermore, the contribution shows the role of the orography of Catalonia in the development of convective structures. This work has been developed in the framework of the Spanish project HOPE.

  9. A Machine Learning Method for Power Prediction on the Mobile Devices.

    PubMed

    Chen, Da-Ren; Chen, You-Shyang; Chen, Lin-Chih; Hsu, Ming-Yang; Chiang, Kai-Feng

    2015-10-01

    Energy profiling and estimation have been popular areas of research in multicore mobile architectures. While short sequences of system calls have been recognized by machine learning as pattern descriptions for anomalous detection, power consumption of running processes with respect to system-call patterns are not well studied. In this paper, we propose a fuzzy neural network (FNN) for training and analyzing process execution behaviour with respect to series of system calls, parameters and their power consumptions. On the basis of the patterns of a series of system calls, we develop a power estimation daemon (PED) to analyze and predict the energy consumption of the running process. In the initial stage, PED categorizes sequences of system calls as functional groups and predicts their energy consumptions by FNN. In the operational stage, PED is applied to identify the predefined sequences of system calls invoked by running processes and estimates their energy consumption.

  10. Synthesis, PtS-type structure, and anomalous mechanics of the Cd(CN)2 precursor Cd(NH3)2[Cd(CN)4].

    PubMed

    Coates, Chloe S; Makepeace, Joshua W; Seel, Andrew G; Baise, Mia; Slater, Ben; Goodwin, Andrew L

    2018-05-15

    We report the nonaqueous synthesis of Cd(CN)2 by oxidation of cadmium metal with Hg(CN)2 in liquid ammonia. The reaction proceeds via an intermediate of composition Cd(NH3)2[Cd(CN)4], which converts to Cd(CN)2 on prolonged heating. Powder X-ray diffraction measurements allow us to determine the crystal structure of the previously-unreported Cd(NH3)2[Cd(CN)4], which we find to adopt a twofold interpenetrating PtS topology. We discuss the effect of partial oxidation on the Cd/Hg composition of this intermediate, as well as its implications for the reconstructive nature of the deammination process. Variable-temperature X-ray diffraction measurements allow us to characterise the anisotropic negative thermal expansion (NTE) behaviour of Cd(NH3)2[Cd(CN)4] together with the effect of Cd/Hg substitution; ab initio density functional theory (DFT) calculations reveal a similarly anomalous mechanical response in the form of both negative linear compressibility (NLC) and negative Poisson's ratios.

  11. Variable order fractional Fokker-Planck equations derived from Continuous Time Random Walks

    NASA Astrophysics Data System (ADS)

    Straka, Peter

    2018-08-01

    Continuous Time Random Walk models (CTRW) of anomalous diffusion are studied, where the anomalous exponent β(x) ∈(0 , 1) varies in space. This type of situation occurs e.g. in biophysics, where the density of the intracellular matrix varies throughout a cell. Scaling limits of CTRWs are known to have probability distributions which solve fractional Fokker-Planck type equations (FFPE). This correspondence between stochastic processes and FFPE solutions has many useful extensions e.g. to nonlinear particle interactions and reactions, but has not yet been sufficiently developed for FFPEs of the "variable order" type with non-constant β(x) . In this article, variable order FFPEs (VOFFPE) are derived from scaling limits of CTRWs. The key mathematical tool is the 1-1 correspondence of a CTRW scaling limit to a bivariate Langevin process, which tracks the cumulative sum of jumps in one component and the cumulative sum of waiting times in the other. The spatially varying anomalous exponent is modelled by spatially varying β(x) -stable Lévy noise in the waiting time component. The VOFFPE displays a spatially heterogeneous temporal scaling behaviour, with generalized diffusivity and drift coefficients whose units are length2/timeβ(x) resp. length/timeβ(x). A global change of the time scale results in a spatially varying change in diffusivity and drift. A consequence of the mathematical derivation of a VOFFPE from CTRW limits in this article is that a solution of a VOFFPE can be approximated via Monte Carlo simulations. Based on such simulations, we are able to confirm that the VOFFPE is consistent under a change of the global time scale.

  12. Analytic cognitive style predicts paranormal explanations of anomalous experiences but not the experiences themselves: Implications for cognitive theories of delusions.

    PubMed

    Ross, Robert M; Hartig, Bjoern; McKay, Ryan

    2017-09-01

    It has been proposed that delusional beliefs are attempts to explain anomalous experiences. Why, then, do anomalous experiences induce delusions in some people but not in others? One possibility is that people with delusions have reasoning biases that result in them failing to reject implausible candidate explanations for anomalous experiences. We examine this hypothesis by studying paranormal interpretations of anomalous experiences. We examined whether analytic cognitive style (i.e. the willingness or disposition to critically evaluate outputs from intuitive processing and engage in effortful analytic processing) predicted anomalous experiences and paranormal explanations for these experiences after controlling for demographic variables and cognitive ability. Analytic cognitive style predicted paranormal explanations for anomalous experiences, but not the anomalous experiences themselves. We did not study clinical delusions. Our attempts to control for cognitive ability may have been inadequate. Our sample was predominantly students. Limited analytic cognitive style might contribute to the interpretation of anomalous experiences in terms of delusional beliefs. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Anomaly of the geomagnetic Sq variation in Japan: effect from 3-D subterranean structure or the ocean effect?

    NASA Astrophysics Data System (ADS)

    Kuvshinov, Alexei; Utada, Hisashi

    2010-12-01

    Many years ago Rikitake et al. described the anomalous behaviour of the vertical component Z of the geomagnetic solar quiet (Sq) daily variation field at observatories in central and northern Japan - namely about 2 hr shift of the local noontime peak towards morning hours. They suggested that this anomaly is associated with the anomalous distribution of electrical conductivity in the mantle beneath central Japan. Although a few works have been done to confirm or argue this explanation, no clear answer has been obtained so far. The goal of this work is to understand the nature of this anomaly using our 3-D forward solution. The conductivity model of the Earth includes oceans of laterally variable conductance and conducting mantle either spherically symmetric or 3-D underneath. Data from six Japanese observatories at four seasons for two different years of the solar cycle are analysed. As an inducing ionospheric (Sq) current system, we use those provided by the Comprehensive Model (CM4) of Sabaka et al. Our analysis clearly demonstrates that 3-D induction in the ocean is responsible for the anomalous behaviour of Z daily variations in this region. We also show that the effects from a suite of 3-D mantle models that include mantle wedge and subducting slab are minor compared with the ocean effect.

  14. Anomalous Experiences, Trauma, and Symbolization Processes at the Frontiers between Psychoanalysis and Cognitive Neurosciences

    PubMed Central

    Rabeyron, Thomas; Loose, Tianna

    2015-01-01

    Anomalous or exceptional experiences are uncommon experiences which are usually interpreted as being paranormal by those who report them. These experiences have long remained difficult to explain, but current progress in cognitive neuroscience and psychoanalysis sheds light on the contexts in which they emerge, as well as on their underlying processes. Following a brief description of the different types of anomalous experiences, we underline how they can be better understood at the frontiers between psychoanalysis and cognitive neurosciences. In this regard, three main lines of research are discussed and illustrated, alongside clinical cases which come from a clinical service specializing in anomalous experiences. First, we study the links between anomalous experiences and hallucinatory processes, by showing that anomalous experiences frequently occur as a specific reaction to negative life events, in which case they mainly take the form of non-pathological hallucinations. Next, we propose to analyze these experiences from the perspective of their traumatic aspects and the altered states of consciousness they often imply. Finally, these experiences are considered to be the consequence of a hypersensitivity that can be linked to an increase in psychic permeability. In conclusion, these different processes lead us to consider anomalous experiences as primary forms of symbolization and transformation of the subjective experience, especially during, or after traumatic situations. PMID:26732646

  15. Doping-induced disappearance of ice II from water's phase diagram

    NASA Astrophysics Data System (ADS)

    Shephard, Jacob J.; Slater, Ben; Harvey, Peter; Hart, Martin; Bull, Craig L.; Bramwell, Steven T.; Salzmann, Christoph G.

    2018-06-01

    Water and the many phases of ice display a plethora of complex physical properties and phase relationships1-4 that are of paramount importance in a range of settings including processes in Earth's hydrosphere, the geology of icy moons, industry and even the evolution of life. Well-known examples include the unusual behaviour of supercooled water2, the emergent ferroelectric ordering in ice films4 and the fact that the `ordinary' ice Ih floats on water. We report the intriguing observation that ice II, one of the high-pressure phases of ice, disappears in a selective fashion from water's phase diagram following the addition of small amounts of ammonium fluoride. This finding exposes the strict topologically constrained nature of the ice II hydrogen-bond network, which is not found for the competing phases. In analogy to the behaviour of frustrated magnets5, the presence of the exceptional ice II is argued to have a wider impact on water's phase diagram, potentially explaining its general tendency to display anomalous behaviour. Furthermore, the impurity-induced disappearance of ice II raises the prospect that specific dopants may not only be able to suppress certain phases but also induce the formation of new phases of ice in future studies.

  16. Waving and skewing: how gravity and the surface of growth media affect root development in Arabidopsis.

    PubMed

    Oliva, Michele; Dunand, Christophe

    2007-01-01

    Arabidopsis seedlings growing on inclined agar surfaces exhibit characteristic root behaviours called 'waving' and 'skewing': the former consists of a series of undulations, whereas the latter is a deviation from the direction of gravity. Even though the precise basis of these growth patterns is not well understood, both gravity and the contact between the medium and the root are considered to be the major players that result in these processes. The influence of these forces on root surface-dependent behaviours can be verified by growing seedlings at different gel pitches: plants growing on vertical plates present roots with slight waving and skewing when compared with seedlings grown on plates held at minor angles of < 90 degrees . However, other factors are thought to modulate root growth on agar; for instance, it has been demonstrated that the presence and concentration of certain compounds in the medium (such as sucrose) and of drugs able to modify the plant cell cytoskeleton also affect skewing and waving. The recent discovery of an active role of ethylene on surface-dependent root behaviour, and the finding of new mutants showing anomalous growth, pave the way for a more detailed description of these phenomena.

  17. The debate on the prognostic value of earthquake foreshocks: a meta-analysis.

    PubMed

    Mignan, Arnaud

    2014-02-14

    The hypothesis that earthquake foreshocks have a prognostic value is challenged by simulations of the normal behaviour of seismicity, where no distinction between foreshocks, mainshocks and aftershocks can be made. In the former view, foreshocks are passive tracers of a tectonic preparatory process that yields the mainshock (i.e., loading by aseismic slip) while in the latter, a foreshock is any earthquake that triggers a larger one. Although both processes can coexist, earthquake prediction is plausible in the first case while virtually impossible in the second. Here I present a meta-analysis of 37 foreshock studies published between 1982 and 2013 to show that the justification of one hypothesis or the other depends on the selected magnitude interval between minimum foreshock magnitude m(min) and mainshock magnitude M. From this literature survey, anomalous foreshocks are found to emerge when m(min) < M - 3.0. These results suggest that a deviation from the normal behaviour of seismicity may be observed only when microseismicity is considered. These results are to be taken with caution since the 37 studies do not all show the same level of reliability. These observations should nonetheless encourage new research in earthquake predictability with focus on the potential role of microseismicity.

  18. Improving GNSS time series for volcano monitoring: application to Canary Islands (Spain)

    NASA Astrophysics Data System (ADS)

    García-Cañada, Laura; Sevilla, Miguel J.; Pereda de Pablo, Jorge; Domínguez Cerdeña, Itahiza

    2017-04-01

    The number of permanent GNSS stations has increased significantly in recent years for different geodetic applications such as volcano monitoring, which require a high precision. Recently we have started to have coordinates time series long enough so that we can apply different analysis and filters that allow us to improve the GNSS coordinates results. Following this idea we have processed data from GNSS permanent stations used by the Spanish Instituto Geográfico Nacional (IGN) for volcano monitoring in Canary Islands to obtained time series by double difference processing method with Bernese v5.0 for the period 2007-2014. We have identified the characteristics of these time series and obtained models to estimate velocities with greater accuracy and more realistic uncertainties. In order to improve the results we have used two kinds of filters to improve the time series. The first, a spatial filter, has been computed using the series of residuals of all stations in the Canary Islands without an anomalous behaviour after removing a linear trend. This allows us to apply this filter to all sets of coordinates of the permanent stations reducing their dispersion. The second filter takes account of the temporal correlation in the coordinate time series for each station individually. A research about the evolution of the velocity depending on the series length has been carried out and it has demonstrated the need for using time series of at least four years. Therefore, in those stations with more than four years of data, we calculated the velocity and the characteristic parameters in order to have time series of residuals. This methodology has been applied to the GNSS data network in El Hierro (Canary Islands) during the 2011-2012 eruption and the subsequent magmatic intrusions (2012-2014). The results show that in the new series it is easier to detect anomalous behaviours in the coordinates, so they are most useful to detect crustal deformations in volcano monitoring.

  19. Feynman-Kac equation for anomalous processes with space- and time-dependent forces

    NASA Astrophysics Data System (ADS)

    Cairoli, Andrea; Baule, Adrian

    2017-04-01

    Functionals of a stochastic process Y(t) model many physical time-extensive observables, for instance particle positions, local and occupation times or accumulated mechanical work. When Y(t) is a normal diffusive process, their statistics are obtained as the solution of the celebrated Feynman-Kac equation. This equation provides the crucial link between the expected values of diffusion processes and the solutions of deterministic second-order partial differential equations. When Y(t) is non-Brownian, e.g. an anomalous diffusive process, generalizations of the Feynman-Kac equation that incorporate power-law or more general waiting time distributions of the underlying random walk have recently been derived. A general representation of such waiting times is provided in terms of a Lévy process whose Laplace exponent is directly related to the memory kernel appearing in the generalized Feynman-Kac equation. The corresponding anomalous processes have been shown to capture nonlinear mean square displacements exhibiting crossovers between different scaling regimes, which have been observed in numerous experiments on biological systems like migrating cells or diffusing macromolecules in intracellular environments. However, the case where both space- and time-dependent forces drive the dynamics of the generalized anomalous process has not been solved yet. Here, we present the missing derivation of the Feynman-Kac equation in such general case by using the subordination technique. Furthermore, we discuss its extension to functionals explicitly depending on time, which are of particular relevance for the stochastic thermodynamics of anomalous diffusive systems. Exact results on the work fluctuations of a simple non-equilibrium model are obtained. An additional aim of this paper is to provide a pedagogical introduction to Lévy processes, semimartingales and their associated stochastic calculus, which underlie the mathematical formulation of anomalous diffusion as a subordinated process.

  20. Control Networks in Paediatric Tourette Syndrome Show Immature and Anomalous Patterns of Functional Connectivity

    ERIC Educational Resources Information Center

    Church, Jessica A.; Fair, Damien A.; Dosenbach, Nico U. F.; Cohen, Alexander L.; Miezin, Francis M.; Petersen, Steven E.; Schlaggar, Bradley L.

    2009-01-01

    Tourette syndrome (TS) is a developmental disorder characterized by unwanted, repetitive behaviours that manifest as stereotyped movements and vocalizations called "tics". Operating under the hypothesis that the brain's control systems may be impaired in TS, we measured resting-state functional connectivity MRI (rs-fcMRI) between 39 previously…

  1. Electrodeposition of quaternary alloys in the presence of magnetic field

    PubMed Central

    2010-01-01

    Electrodeposition of Ni-Co-Fe-Zn alloys was done in a chloride ion solution with the presence and absence of a Permanent Parallel Magnetic Field (PPMF). The PPMF was applied parallel to the cathode surface. The deposition profile was monitored chronoamperometrically. It was found that the electrodeposition current was enhanced in the presence of PPMF (9 T) compared to without PPMF. The percentage of current enhancement (Γ%) was increased in the presence of PPMF, with results of Γ% = 11.9%, 16.7% and 18.5% at -1.1, -1.2 and -1.3 V respectively for a 2400 sec duration. In chronoamperometry, the Composition Reference Line (CRL) for Ni was around 57%, although the nobler metals (i.e. Ni, Co) showed anomalous behaviour in the presence of Zn and Fe. The anomalous behaviour of the Ni-Co-Fe-Zn electrodeposition was shown by the Energy Dispersive X-Ray (EDX) results. From Atomic Force Microscopy (AFM) measurements, it was found that the surface roughness of the Ni-Co-Fe-Zn alloy films decreased in the presence of a PPMF. PMID:20604934

  2. Multi-Level Modeling of Complex Socio-Technical Systems - Phase 1

    DTIC Science & Technology

    2013-06-06

    is to detect anomalous organizational outcomes, diagnose the causes of these anomalies , and decide upon appropriate compensation schemes. All of...monitor process outcomes. The purpose of this monitoring is to detect anomalous process outcomes, diagnose the causes of these anomalies , and decide upon...monitor work outcomes in terms of performance. The purpose of this monitoring is to detect anomalous work outcomes, diagnose the causes of these anomalies

  3. The recursive combination filter approach of pre-processing for the estimation of standard deviation of RR series.

    PubMed

    Mishra, Alok; Swati, D

    2015-09-01

    Variation in the interval between the R-R peaks of the electrocardiogram represents the modulation of the cardiac oscillations by the autonomic nervous system. This variation is contaminated by anomalous signals called ectopic beats, artefacts or noise which mask the true behaviour of heart rate variability. In this paper, we have proposed a combination filter of recursive impulse rejection filter and recursive 20% filter, with recursive application and preference of replacement over removal of abnormal beats to improve the pre-processing of the inter-beat intervals. We have tested this novel recursive combinational method with median method replacement to estimate the standard deviation of normal to normal (SDNN) beat intervals of congestive heart failure (CHF) and normal sinus rhythm subjects. This work discusses the improvement in pre-processing over single use of impulse rejection filter and removal of abnormal beats for heart rate variability for the estimation of SDNN and Poncaré plot descriptors (SD1, SD2, and SD1/SD2) in detail. We have found the 22 ms value of SDNN and 36 ms value of SD2 descriptor of Poincaré plot as clinical indicators in discriminating the normal cases from CHF cases. The pre-processing is also useful in calculation of Lyapunov exponent which is a nonlinear index as Lyapunov exponents calculated after proposed pre-processing modified in a way that it start following the notion of less complex behaviour of diseased states.

  4. Superstatistical generalised Langevin equation: non-Gaussian viscoelastic anomalous diffusion

    NASA Astrophysics Data System (ADS)

    Ślęzak, Jakub; Metzler, Ralf; Magdziarz, Marcin

    2018-02-01

    Recent advances in single particle tracking and supercomputing techniques demonstrate the emergence of normal or anomalous, viscoelastic diffusion in conjunction with non-Gaussian distributions in soft, biological, and active matter systems. We here formulate a stochastic model based on a generalised Langevin equation in which non-Gaussian shapes of the probability density function and normal or anomalous diffusion have a common origin, namely a random parametrisation of the stochastic force. We perform a detailed analysis demonstrating how various types of parameter distributions for the memory kernel result in exponential, power law, or power-log law tails of the memory functions. The studied system is also shown to exhibit a further unusual property: the velocity has a Gaussian one point probability density but non-Gaussian joint distributions. This behaviour is reflected in the relaxation from a Gaussian to a non-Gaussian distribution observed for the position variable. We show that our theoretical results are in excellent agreement with stochastic simulations.

  5. Anomalous scaling of stochastic processes and the Moses effect

    NASA Astrophysics Data System (ADS)

    Chen, Lijian; Bassler, Kevin E.; McCauley, Joseph L.; Gunaratne, Gemunu H.

    2017-04-01

    The state of a stochastic process evolving over a time t is typically assumed to lie on a normal distribution whose width scales like t1/2. However, processes in which the probability distribution is not normal and the scaling exponent differs from 1/2 are known. The search for possible origins of such "anomalous" scaling and approaches to quantify them are the motivations for the work reported here. In processes with stationary increments, where the stochastic process is time-independent, autocorrelations between increments and infinite variance of increments can cause anomalous scaling. These sources have been referred to as the Joseph effect and the Noah effect, respectively. If the increments are nonstationary, then scaling of increments with t can also lead to anomalous scaling, a mechanism we refer to as the Moses effect. Scaling exponents quantifying the three effects are defined and related to the Hurst exponent that characterizes the overall scaling of the stochastic process. Methods of time series analysis that enable accurate independent measurement of each exponent are presented. Simple stochastic processes are used to illustrate each effect. Intraday financial time series data are analyzed, revealing that their anomalous scaling is due only to the Moses effect. In the context of financial market data, we reiterate that the Joseph exponent, not the Hurst exponent, is the appropriate measure to test the efficient market hypothesis.

  6. Anomalous scaling of stochastic processes and the Moses effect.

    PubMed

    Chen, Lijian; Bassler, Kevin E; McCauley, Joseph L; Gunaratne, Gemunu H

    2017-04-01

    The state of a stochastic process evolving over a time t is typically assumed to lie on a normal distribution whose width scales like t^{1/2}. However, processes in which the probability distribution is not normal and the scaling exponent differs from 1/2 are known. The search for possible origins of such "anomalous" scaling and approaches to quantify them are the motivations for the work reported here. In processes with stationary increments, where the stochastic process is time-independent, autocorrelations between increments and infinite variance of increments can cause anomalous scaling. These sources have been referred to as the Joseph effect and the Noah effect, respectively. If the increments are nonstationary, then scaling of increments with t can also lead to anomalous scaling, a mechanism we refer to as the Moses effect. Scaling exponents quantifying the three effects are defined and related to the Hurst exponent that characterizes the overall scaling of the stochastic process. Methods of time series analysis that enable accurate independent measurement of each exponent are presented. Simple stochastic processes are used to illustrate each effect. Intraday financial time series data are analyzed, revealing that their anomalous scaling is due only to the Moses effect. In the context of financial market data, we reiterate that the Joseph exponent, not the Hurst exponent, is the appropriate measure to test the efficient market hypothesis.

  7. Anomalous CO2 Emissions in Different Ecosystems Around the World

    NASA Astrophysics Data System (ADS)

    Sanchez-Canete, E. P.; Moya Jiménez, M. R.; Kowalski, A. S.; Serrano-Ortiz, P.; López-Ballesteros, A.; Oyonarte, C.; Domingo, F.

    2016-12-01

    As an important tool for understanding and monitoring ecosystem dynamics at ecosystem level, the eddy covariance (EC) technique allows the assessment of the diurnal and seasonal variation of the net ecosystem exchange (NEE). Despite the high temporal resolution data available, there are still many processes (in addition to photosynthesis and respiration) that, although they are being monitored, have been neglected. Only a few authors have studied anomalous CO2 emissions (non biological), and have related them to soil ventilation, photodegradation or geochemical processes. The aim of this study is: 1) to identify anomalous short term CO2 emissions in different ecosystems distributed around the world, 2) to determine the meteorological variables that are influencing these emissions, and 3) to explore the potential processes that can be involved. We have studied EC data together with other meteorological ancillary variables obtained from the FLUXNET database (version 2015) and have found more than 50 sites with anomalous CO2 emissions in different ecosystem types such as grasslands, croplands or savannas. Data were filtered according to the FLUXNET quality control flags (only data with quality control flag equal to 0 was used) and correlation analysis were performed with NEE and ancillary data. Preliminary results showed strong and highly significant correlations between meteorological variables and anomalous CO2 emissions. Correlation results showed clear differing behaviors between ecosystems types, which could be related to the different processes involved in the anomalous CO2 emissions. We suggest that anomalous CO2 emissions are happening globally and therefore, their contribution to the global net ecosystem carbon balance requires further investigation in order to better understand its drivers.

  8. Multiphoton Process and Anomalous Potential of Cell Membrane by Laser Radiation

    NASA Technical Reports Server (NTRS)

    Zhang, Kaixi; Zhao, Qingxun; Cui, Zhiyun; Zhar, Ping; Dong, Lifang

    1996-01-01

    In this paper, by the use of quantum biology and quantum optics, the laser induced potential variation of cell membrane has been studied. Theoretically, we have found a method of calculating the monophoton and multiphoton processes in the formation of the anomalous potential of cell membrane. In contrast with the experimental results, our numerical result is in the same order. Therefore, we have found the possibility of cancer caused by the laser induced anomalous cell potential.

  9. Generalized fractional diffusion equations for accelerating subdiffusion and truncated Lévy flights

    NASA Astrophysics Data System (ADS)

    Chechkin, A. V.; Gonchar, V. Yu.; Gorenflo, R.; Korabel, N.; Sokolov, I. M.

    2008-08-01

    Fractional diffusion equations are widely used to describe anomalous diffusion processes where the characteristic displacement scales as a power of time. For processes lacking such scaling the corresponding description may be given by diffusion equations with fractional derivatives of distributed order. Such equations were introduced in A. V. Chechkin, R. Gorenflo, and I. Sokolov [Phys. Rev. E 66, 046129 (2002)] for the description of the processes getting more anomalous in the course of time (decelerating subdiffusion and accelerating superdiffusion). Here we discuss the properties of diffusion equations with fractional derivatives of the distributed order for the description of anomalous relaxation and diffusion phenomena getting less anomalous in the course of time, which we call, respectively, accelerating subdiffusion and decelerating superdiffusion. For the former process, by taking a relatively simple particular example with two fixed anomalous diffusion exponents we show that the proposed equation effectively describes the subdiffusion phenomenon with diffusion exponent varying in time. For the latter process we demonstrate by a particular example how the power-law truncated Lévy stable distribution evolves in time to the distribution with power-law asymptotics and Gaussian shape in the central part. The special case of two different orders is characteristic for the general situation in which the extreme orders dominate the asymptotics.

  10. A novel instrument for studying the flow behaviour of erythrocytes through microchannels simulating human blood capillaries.

    PubMed

    Sutton, N; Tracey, M C; Johnston, I D; Greenaway, R S; Rampling, M W

    1997-05-01

    A novel instrument has been developed to study the microrheology of erythrocytes as they flow through channels of dimensions similar to human blood capillaries. The channels are produced in silicon substrates using microengineering technology. Accurately defined, physiological driving pressures and temperatures are employed whilst precise, real-time image processing allows individual cells to be monitored continuously during their transit. The instrument characterises each cell in a sample of ca. 1000 in terms of its volume and flow velocity profile during its transit through a channel. The unique representation of the data in volume/velocity space provides new insight into the microrheological behaviour of blood. The image processing and subsequent data analysis enable the system to reject anomalous events such as multiple cell transits, thereby ensuring integrity of the resulting data. By employing an array of microfluidic flow channels we can integrate a number of different but precise and highly reproducible channel sizes and geometries within one array, thereby allowing multiple, concurrent isobaric measurements on one sample. As an illustration of the performance of the system, volume/velocity data sets recorded in a microfluidic device incorporating multiple channels of 100 microns length and individual widths ranging between 3.0 and 4.0 microns are presented.

  11. The debate on the prognostic value of earthquake foreshocks: A meta-analysis

    PubMed Central

    Mignan, Arnaud

    2014-01-01

    The hypothesis that earthquake foreshocks have a prognostic value is challenged by simulations of the normal behaviour of seismicity, where no distinction between foreshocks, mainshocks and aftershocks can be made. In the former view, foreshocks are passive tracers of a tectonic preparatory process that yields the mainshock (i.e., loading by aseismic slip) while in the latter, a foreshock is any earthquake that triggers a larger one. Although both processes can coexist, earthquake prediction is plausible in the first case while virtually impossible in the second. Here I present a meta-analysis of 37 foreshock studies published between 1982 and 2013 to show that the justification of one hypothesis or the other depends on the selected magnitude interval between minimum foreshock magnitude mmin and mainshock magnitude M. From this literature survey, anomalous foreshocks are found to emerge when mmin < M − 3.0. These results suggest that a deviation from the normal behaviour of seismicity may be observed only when microseismicity is considered. These results are to be taken with caution since the 37 studies do not all show the same level of reliability. These observations should nonetheless encourage new research in earthquake predictability with focus on the potential role of microseismicity. PMID:24526224

  12. Effects of eletron heating on the current driven electrostatic ion cyclotron instability and plasma transport processes along auroral field lines

    NASA Technical Reports Server (NTRS)

    Ganguli, Supriya B.; Mitchell, Horace G.; Palmadesso, Peter J.

    1988-01-01

    Fluid simulations of the plasma along auroral field lines in the return current region have been performed. It is shown that the onset of electrostatic ion cyclotron (EIC) related anomalous resistivity and the consequent heating of electrons leads to a transverse ion temperature that is much higher than that produced by the current driven EIC instability (CDICI) alone. Two processes are presented for the enhancement of ion heating by anomalous resistivity. The anomalous resistivity associated with the turbulence is limited by electron heating, so that CDICI saturates at transverse temperature that is substantially higher than in the absence of resistivity. It is suggested that this process demonstrates a positive feedback loop in the interaction between CDICI, anomalous resistivity, and parallel large-scale dynamics in the topside ionosphere.

  13. Tissue microstructure features derived from anomalous diffusion measurements in magnetic resonance imaging.

    PubMed

    Yu, Qiang; Reutens, David; O'Brien, Kieran; Vegh, Viktor

    2017-02-01

    Tissue microstructure features, namely axon radius and volume fraction, provide important information on the function of white matter pathways. These parameters vary on the scale much smaller than imaging voxels (microscale) yet influence the magnetic resonance imaging diffusion signal at the image voxel scale (macroscale) in an anomalous manner. Researchers have already mapped anomalous diffusion parameters from magnetic resonance imaging data, but macroscopic variations have not been related to microscale influences. With the aid of a tissue model, we aimed to connect anomalous diffusion parameters to axon radius and volume fraction using diffusion-weighted magnetic resonance imaging measurements. An ex vivo human brain experiment was performed to directly validate axon radius and volume fraction measurements in the human brain. These findings were validated using electron microscopy. Additionally, we performed an in vivo study on nine healthy participants to map axon radius and volume fraction along different regions of the corpus callosum projecting into various cortical areas identified using tractography. We found a clear relationship between anomalous diffusion parameters and axon radius and volume fraction. We were also able to map accurately the trend in axon radius along the corpus callosum, and in vivo findings resembled the low-high-low-high behaviour in axon radius demonstrated previously. Axon radius and volume fraction measurements can potentially be used in brain connectivity studies and to understand the implications of white matter structure in brain diseases and disorders. Hum Brain Mapp 38:1068-1081, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  14. General practitioners and the independent contractor status

    PubMed Central

    Gray, D. J. Pereira

    1977-01-01

    Primary medical care can be provided either by a bureaucratic hierarchical organization or alternatively by independent contractors. Most members of the caring professions in medicine, nursing, and social work are employed in bureaucracies, whereas general medical practitioners, general dental practitioners, opticians, and pharmacists are independent contractors. The independent contractor status has recently been heavily attacked from within the medical and nursing professions, and also from outside. It has been suggested that contracting for services is an inappropriate and anomalous way of arranging medical care, which should now be stopped. However, this process of contracting for services can be analysed, using perspectives from some of the behavioural sciences, to reveal hidden depths in the independent contractor status which suggest that the provision of primary medical care is best carried out by independent contractors. PMID:616865

  15. Tellurium - Should it be isotopically anomalous in the Allende meteorite

    NASA Technical Reports Server (NTRS)

    Heymann, D.; Dziczkaniec, M.

    1981-01-01

    Isotopically anomalous Te is a by-product of the nuclear processes in zones of supernovae that have been proposed as sources for isotopically anomalous Xe. The calculated composition of the anomalous Te is roughly consistent with the disputed measurements made by Ballad et at. (1979) and Oliver et al. (1979) of samples of the Allende meteorite, with the exception that the large Te-123 overabundance reported by Oliver et al. (1979) is not predicted by the theory.

  16. Children's Responses to Anomalous Scientific Data: How Is Conceptual Change Impeded?

    ERIC Educational Resources Information Center

    Chinn, Clark A.; Malhotra, Betina A.

    2002-01-01

    Four experiments with 4th, 5th, and 6th graders addressed conceptual change in response to anomalous data about empirical regularities in science. Impedance to conceptual change in response to anomalous data could potentially occur at any of four cognitive processes: observation, interpretation, generalization, or retention. In the four…

  17. Anomalous decay and scattering processes of the meson

    NASA Astrophysics Data System (ADS)

    Kubis, Bastian; Plenter, Judith

    2015-06-01

    We amend a recent dispersive analysis of the anomalous decay process by the effects of the tensor meson, the lowest-lying resonance that can contribute in the system. While the net effects on the measured decay spectrum are small, they may be more pronounced for the analogous decay. There are nonnegligible consequences for the transition form factor, which is an important quantity for the hadronic light-by-light scattering contribution to the muon's anomalous magnetic moment. We predict total and differential cross sections, as well as a marked forward-backward asymmetry, for the crossed process , which could be measured in Primakoff reactions in the future.

  18. Anomalous quartic couplings in W+W- gamma production at e+e- colliders

    NASA Astrophysics Data System (ADS)

    Leil, G. A.; Stirling, W. J.

    1995-04-01

    We study the process $e^+e^- \\rightarrow W^+W^- \\gamma$ at high-energy $e^+ e^-$ colliders to investigate the effect of genuine quartic $W^+W^-\\gamma\\gamma$ and $W^+W^- Z\\gamma$ anomalous couplings on the cross section. Deviations from the Standard Model predictions are quantified. We show how bounds on the anomalous couplings can be improved by choosing specific initial state helicity combinations. The dependence of the anomalous contributions on the collider energy is studied.

  19. Anomalous neuronal responses to fluctuated inputs

    NASA Astrophysics Data System (ADS)

    Hosaka, Ryosuke; Sakai, Yutaka

    2015-10-01

    The irregular firing of a cortical neuron is thought to result from a highly fluctuating drive that is generated by the balance of excitatory and inhibitory synaptic inputs. A previous study reported anomalous responses of the Hodgkin-Huxley neuron to the fluctuated inputs where an irregularity of spike trains is inversely proportional to an input irregularity. In the current study, we investigated the origin of these anomalous responses with the Hindmarsh-Rose neuron model, map-based models, and a simple mixture of interspike interval distributions. First, we specified the parameter regions for the bifurcations in the Hindmarsh-Rose model, and we confirmed that the model reproduced the anomalous responses in the dynamics of the saddle-node and subcritical Hopf bifurcations. For both bifurcations, the Hindmarsh-Rose model shows bistability in the resting state and the repetitive firing state, which indicated that the bistability was the origin of the anomalous input-output relationship. Similarly, the map-based model that contained bistability reproduced the anomalous responses, while the model without bistability did not. These results were supported by additional findings that the anomalous responses were reproduced by mimicking the bistable firing with a mixture of two different interspike interval distributions. Decorrelation of spike trains is important for neural information processing. For such spike train decorrelation, irregular firing is key. Our results indicated that irregular firing can emerge from fluctuating drives, even weak ones, under conditions involving bistability. The anomalous responses, therefore, contribute to efficient processing in the brain.

  20. Anomalous single production of the fourth generation quarks at the CERN LHC

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ciftci, R.

    Possible anomalous single productions of the fourth standard model generation up and down type quarks at CERN Large Hadron Collider are studied. Namely, pp{yields}u{sub 4}(d{sub 4})X with subsequent u{sub 4}{yields}bW{sup +} process followed by the leptonic decay of the W boson and d{sub 4}{yields}b{gamma} (and its H.c.) decay channel are considered. Signatures of these processes and corresponding standard model backgrounds are discussed in detail. Discovery limits for the quark mass and achievable values of the anomalous coupling strength are determined.

  1. IR-stimulated visible fluorescence in pink and brown diamond.

    PubMed

    Byrne, K S; Chapman, J G; Luiten, A N

    2014-03-19

    Irradiation of natural pink and brown diamond by middle-ultraviolet light (photon energy ϵ ≥ 4.1 eV ) is seen to induce anomalous fluorescence phenomena at N3 defect centres (structure N3-V). When diamonds primed in this fashion are subsequently exposed to infrared light (even with a delay of many hours), a transient burst of blue N3 fluorescence is observed. The dependence of this IR-triggered fluorescence on pump wavelength and intensity suggest that this fluorescence phenomena is intrinsically related to pink diamond photochromism. An energy transfer process between N3 defects and other defect species can account for both the UV-induced fluorescence intensity changes, and the apparent optical upconversion of IR light. From this standpoint, we consider the implications of this N3 fluorescence behaviour for the current understanding of pink diamond photochromism kinetics.

  2. Anomalous single production of fourth family up-type quark associated with neutral gauge bosons at the LHC

    NASA Astrophysics Data System (ADS)

    Çakır, O.; Çakır, I. T.; Senol, A.; Tasci, A. T.

    2012-05-01

    The fourth family quarks are expected to have mass larger than the top quark considering the results from recent studies on the allowed parameter space. They could also have different dynamics than the quarks of three families of the standard model. The single production of the fourth family up-type quark t‧ is studied via the anomalous production process pp → t‧VX (where V = g, Z, γ) at the LHC with the center of mass energy of 7 and 14 TeV. The signatures of such process are discussed within both the SM and the anomalous decay modes of t‧ quarks. The sensitivity to anomalous coupling κ/Λ = 0.004 TeV-1 can be reached at \\sqrt{s}=14 TeV and Lint = 100 pb-1.

  3. Electrodynamical Model of Quasi-Efficient Financial Markets

    NASA Astrophysics Data System (ADS)

    Ilinski, Kirill N.; Stepanenko, Alexander S.

    The modelling of financial markets presents a problem which is both theoretically challenging and practically important. The theoretical aspects concern the issue of market efficiency which may even have political implications [1], whilst the practical side of the problem has clear relevance to portfolio management [2] and derivative pricing [3]. Up till now all market models contain "smart money" traders and "noise" traders whose joint activity constitutes the market [4, 5]. On a short time scale this traditional separation does not seem to be realistic, and is hardly acceptable since all high-frequency market participants are professional traders and cannot be separated into "smart" and "noisy." In this paper we present a "microscopic" model with homogenuous quasi-rational behaviour of traders, aiming to describe short time market behaviour. To construct the model we use an analogy between "screening" in quantum electrodynamics and an equilibration process in a market with temporal mispricing [6, 7]. As a result, we obtain the time-dependent distribution function of the returns which is in quantitative agreement with real market data and obeys the anomalous scaling relations recently reported for both high-frequency exchange rates [8], S&P500 [9] and other stock market indices [10, 11].

  4. Incremental comprehension of pitch relationships in written music: Evidence from eye movements.

    PubMed

    Hadley, Lauren V; Sturt, Patrick; Eerola, Tuomas; Pickering, Martin J

    2017-03-17

    To investigate how proficient pianists comprehend pitch relationships in written music when they first encounter it we conducted two experiments in which proficient pianists' eyes were tracked while they read and played single-line melodies. In Experiment 1, participants played at their own speed; in Experiment 2 they played with an external metronome. The melodies were either congruent or anomalous, with the anomaly involving one bar being shifted in pitch to alter the implied harmonic structure (e.g., non-resolution of a dominant). In both experiments, anomaly led to rapid disruption in participants' eye-movements in terms of regressions from the target bar, indicating that pianists process written pitch relationships online. This is particularly striking because in musical sight-reading eye movement behaviour is constrained by the concurrent performance. Both experiments also showed that anomaly induced pupil dilation. Together these results indicate that proficient pianists rapidly integrate the music that they read into the prior context, and that anomalies in terms of pitch relationships lead to processing difficulty. These findings parallel those of text reading, suggesting that structural processing involves similar constraints across domains.

  5. Genetic profiling links changing sea-ice to shifting beluga whale migration patterns

    PubMed Central

    Mahoney, Andrew R.; Suydam, Robert; Quakenbush, Lori; Whiting, Alex; Lowry, Lloyd; Harwood, Lois

    2016-01-01

    There is increasing concern over how Arctic fauna will adapt to climate related changes in sea-ice. We used long-term sighting and genetic data on beluga whales (Delphinapterus leucas) in conjunction with multi-decadal patterns of sea-ice in the Pacific Arctic to investigate the influence of sea-ice on spring migration and summer residency patterns. Substantial variations in sea-ice conditions were detected across seasons, years and sub-regions, revealing ice–ocean dynamics more complex than Arctic-wide trends suggest. This variation contrasted with a highly consistent pattern of migration and residency by several populations, indicating that belugas can accommodate widely varying sea-ice conditions to perpetuate philopatry to coastal migration destinations. However, a number of anomalous migration and residency events were detected and coincided with anomalous ice years, and in one case with an increase in killer whale (Orcinus orca) sightings and reported predation on beluga whales. The behavioural shifts were likely driven by changing sea-ice and associated changes in resource dispersion and predation risk. Continued reductions in sea-ice may result in increased predation at key aggregation areas and shifts in beluga whale behaviour with implications for population viability, ecosystem structure and the subsistence cultures that rely on them.

  6. Anomalous Resistance Hysteresis in Oxide ReRAM: Oxygen Evolution and Reincorporation Revealed by In Situ TEM.

    PubMed

    Cooper, David; Baeumer, Christoph; Bernier, Nicolas; Marchewka, Astrid; La Torre, Camilla; Dunin-Borkowski, Rafal E; Menzel, Stephan; Waser, Rainer; Dittmann, Regina

    2017-06-01

    The control and rational design of redox-based memristive devices, which are highly attractive candidates for next-generation nonvolatile memory and logic applications, is complicated by competing and poorly understood switching mechanisms, which can result in two coexisting resistance hystereses that have opposite voltage polarity. These competing processes can be defined as regular and anomalous resistive switching. Despite significant characterization efforts, the complex nanoscale redox processes that drive anomalous resistive switching and their implications for current transport remain poorly understood. Here, lateral and vertical mapping of O vacancy concentrations is used during the operation of such devices in situ in an aberration corrected transmission electron microscope to explain the anomalous switching mechanism. It is found that an increase (decrease) in the overall O vacancy concentration within the device after positive (negative) biasing of the Schottky-type electrode is associated with the electrocatalytic release and reincorporation of oxygen at the electrode/oxide interface and is responsible for the resistance change. This fundamental insight presents a novel perspective on resistive switching processes and opens up new technological opportunities for the implementation of memristive devices, as anomalous switching can now be suppressed selectively or used deliberately to achieve the desirable so-called deep Reset. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Computational analysis of the roles of biochemical reactions in anomalous diffusion dynamics

    NASA Astrophysics Data System (ADS)

    Naruemon, Rueangkham; Charin, Modchang

    2016-04-01

    Most biochemical processes in cells are usually modeled by reaction-diffusion (RD) equations. In these RD models, the diffusive process is assumed to be Gaussian. However, a growing number of studies have noted that intracellular diffusion is anomalous at some or all times, which may result from a crowded environment and chemical kinetics. This work aims to computationally study the effects of chemical reactions on the diffusive dynamics of RD systems by using both stochastic and deterministic algorithms. Numerical method to estimate the mean-square displacement (MSD) from a deterministic algorithm is also investigated. Our computational results show that anomalous diffusion can be solely due to chemical reactions. The chemical reactions alone can cause anomalous sub-diffusion in the RD system at some or all times. The time-dependent anomalous diffusion exponent is found to depend on many parameters, including chemical reaction rates, reaction orders, and chemical concentrations. Project supported by the Thailand Research Fund and Mahidol University (Grant No. TRG5880157), the Thailand Center of Excellence in Physics (ThEP), CHE, Thailand, and the Development Promotion of Science and Technology.

  8. In vitro development of Haemoproteus parasites: the efficiency of reproductive cells increase during simultaneous sexual process of different lineages.

    PubMed

    Valkiūnas, Gediminas; Palinauskas, Vaidas; Ilgūnas, Mikas; Bernotienė, Rasa; Iezhova, Tatjana A

    2014-04-01

    Recent in vitro experimental studies reported the complex patterns of haemosporidian (Haemosporida) between-lineage interactions, which prevent mixing of lineages during simultaneous sexual process. Numerous anomalous ookinetes have been observed; these are not involved in sporogony. Massive development of such ookinetes might influence parasite transmission but is insufficiently investigated. The simultaneous sexual process of several lineages is a common phenomenon in vectors due to high prevalence of haemosporidian co-infections in wildlife. It remains unclear if the number of anomalous ookinetes changes during dual-infection sporogony in comparison with the single-infection process. We calculated proportions of the anomalous and normal ookinetes, which developed during single-infection (control) and dual-infection experiments in vitro conditions. Three mitochondrial cytochrome b lineages belonging to three Haemoproteus spp. (Haemosporida, Haemoproteidae) were isolated from naturally infected passerine birds. Sexual process and ookinete development were initiated in vitro by mixing blood containing mature gametocytes of two different parasites; the following experiments were performed: (1) Haemoproteus tartakovskyi (lineage hSISKIN1) × Haemoproteus lanii (lineage hRBS4) and (2) Haemoproteus belopolskyi (hHIICT3) × H. lanii (hRBS4). Genetic difference between lineages was 5.0-5.9%. Normal and anomalous ookinetes developed in all control and dual-infection experiments. The number of anomalous ookinetes markedly decreased, and normal ookinetes increased in all dual-infection experiments in comparison with those in controls, except for H. belopolskyi, in which proportion of the anomalous and normal ookinetes did not change. This study shows that simultaneous sexual process of two genetically distant lineages of haemosporidian parasites might increase the efficiency of reproductive cells, resulting in the development of a greater number of normal ookinetes. The marked increase of the number of normal ookinetes, which is involved in sporogony, indicates the success of sporogony in dual infections. Some haemosporidian lineages might benefit from simultaneous sporogony. Widespread avian Haemoproteus spp. are convenient and laboratory-friendly organisms for in vitro experimental research addressing between-lineage interaction in parasites during the sexual process.

  9. Anomalous resistivity effect on multiple ion beam emission and hard x-ray generation in a Mather type plasma focus device

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Behbahani, R. A.; Aghamir, F. M.

    Multi ion beam and hard x-ray emissions were detected in a high inductance (more than 100 nH) Mather type plasma focus (PF) device at different filling gas pressures and charging voltages. The signal analysis was performed through the current trace, as it is the fundamental signal from which all of the phenomena in a PF device can be extracted. Two different fitting processes were carried out according to Lee's computational (snow-plow) model. In the first process, only plasma dynamics and classical (Spitzer) resistances were considered as energy consumer parameters for plasma. This led to an unsuccessful fitting and did notmore » answer the energy transfer mechanism into plasma. A second fitting process was considered through the addition of anomalous resistance, which provided the best fit. Anomalous resistance was the source of long decrease in current trace, and multi dips and multi peaks of high voltage probe. Multi-peak features were interpreted considering the second fitting process along with the mechanisms for ion beam production and hard x-ray emission. To show the important role of the anomalous resistance, the duration of the current drop was discussed.« less

  10. Measurement and interpretation of fluorescence polarisations in phospholipid dispersions.

    PubMed

    Bashford, C L; Morgan, C G; Radda, G K

    1976-03-05

    An instrument that measures the temperature dependence of fluorescence polarisation and intensity directly and continuously is described. The behaviour of four fluorescent probes bound to a number of well characterised model systems was then examined. The motional properties of the probes were determined from the polarisation and intensity data and were found to be sensitive to the crystalline-liquid crystalline phase transitions in phospholipid vesicles of dimyristoly and dipalmitoly phosphatidylcholine. Binary mixture of dilauroyl and dipalmitoyl phosphatidylcholine show lateral phase separation and in this system the probes parition preferentially into the more 'fluid' phase. In systems that have been reported to contain 'short range order' or 'liquid clustering', such as dioleoyl phosphatidylcholine and liquid paraffin, the motion of the probes was found to have anomalous Arrhenius behaviour consistent with the idea that homogeneous phases were not being sampled. The significance of these findings for the interpretation of the behaviour of fluorescent probes bound to natural membranes is discussed.

  11. Spin of Planetary Probes in Atmospheric Flight

    NASA Astrophysics Data System (ADS)

    Lorenz, R. D.

    Probes that enter planetary atmospheres are often spun during entry or descent for a variety of reasons. Their spin rate histories are influenced by often subtle effects. The spin requirements, control methods and flight experience from planetary and earth entry missions are reviewed. An interaction of the probe aerodynamic wake with a drogue parachute, observed in Gemini wind tunnel tests, is discussed in connection with the anomalous spin behaviour of the Huygens probe.

  12. Graphene Plasmonics for Tunable Terahertz Metamaterials

    DTIC Science & Technology

    2011-10-01

    anomalous quantumHall effect15,16 andKlein tunnelling17,18 in electrical transport to a universal absorption constant19,20 and tunable interband ...electron scattering spectroscopy25,26 and inelastic scanning tunnelling microscopy27. However, the fundamental behaviour of light–plasmon coupling in...ribbon arrays. Here TCNP is the transmission coefficient at CNP and DT¼ T2 TCNP. The 2DT/TCNP spectra of a gated 4 mm sample (Vg¼22.0 V) for terahertz

  13. RSRM Nozzle Anomalous Throat Erosion Investigation Overview

    NASA Technical Reports Server (NTRS)

    Clinton, R. G., Jr.; Wendel, Gary M.

    1998-01-01

    In September, 1996, anomalous pocketing erosion was observed in the aft end of the throat ring of the nozzle of one of the reusable solid rocket motors (RSRM 56B) used on NASA's space transportation system (STS) mission 79. The RSRM throat ring is constructed of bias tape-wrapped carbon cloth/ phenolic (CCP) ablative material. A comprehensive investigation revealed necessary and sufficient conditions for occurrence of the pocketing event and provided rationale that the solid rocket motors for the subsequent mission, STS-80, were safe to fly. The nozzles of both of these motors also exhibited anomalous erosion similar to, but less extensive than that observed on STS-79. Subsequent to this flight, the investigation to identify both the specific causes and the corrective actions for elimination of the necessary and sufficient conditions for the pocketing erosion was intensified. A detailed fault tree approach was utilized to examine potential material and process contributors to the anomalous performance. The investigation involved extensive constituent and component material property testing, pedigree assessments, supplier audits, process audits, full scale processing test article fabrication and evaluation, thermal and thermostructural analyses, nondestructive evaluation, and material performance tests conducted using hot fire simulation in laboratory test beds and subscale and full scale solid rocket motor static test firings. This presentation will provide an over-view of the observed anomalous nozzle erosion and the comprehensive, fault-tree based investigation conducted to resolve this issue.

  14. Fine-Tuning the Accretion Disk Clock in Hercules X-1

    NASA Technical Reports Server (NTRS)

    Still, M.; Boyd, P.

    2004-01-01

    RXTE ASM count rates from the X-ray pulsar Her X-1 began falling consistently during the late months of 2003. The source is undergoing another state transition similar to the anomalous low state of 1999. This new event has triggered observations from both space and ground-based observatories. In order to aid data interpretation and telescope scheduling, and to facilitate the phase-connection of cycles before and after the state transition, we have re-calculated the precession ephemeris using cycles over the last 3.5 years. We report that the source has displayed a different precession period since the last anomalous event. Additional archival data from CGRO suggests that each low state is accompanied by a change in precession period and that the subsequent period is correlated with accretion flux. Consequently our analysis reveals long-term accretion disk behaviour which is predicted by theoretical models of radiation-driven warping.

  15. Anomalous low-temperature Coulomb drag in graphene-GaAs heterostructures.

    PubMed

    Gamucci, A; Spirito, D; Carrega, M; Karmakar, B; Lombardo, A; Bruna, M; Pfeiffer, L N; West, K W; Ferrari, A C; Polini, M; Pellegrini, V

    2014-12-19

    Vertical heterostructures combining different layered materials offer novel opportunities for applications and fundamental studies. Here we report a new class of heterostructures comprising a single-layer (or bilayer) graphene in close proximity to a quantum well created in GaAs and supporting a high-mobility two-dimensional electron gas. In our devices, graphene is naturally hole-doped, thereby allowing for the investigation of electron-hole interactions. We focus on the Coulomb drag transport measurements, which are sensitive to many-body effects, and find that the Coulomb drag resistivity significantly increases for temperatures <5-10 K. The low-temperature data follow a logarithmic law, therefore displaying a notable departure from the ordinary quadratic temperature dependence expected in a weakly correlated Fermi-liquid. This anomalous behaviour is consistent with the onset of strong interlayer correlations. Our heterostructures represent a new platform for the creation of coherent circuits and topologically protected quantum bits.

  16. Anomalous evolution of Ar metastable density with electron density in high density Ar discharge

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Park, Min; Chang, Hong-Young; You, Shin-Jae

    2011-10-15

    Recently, an anomalous evolution of argon metastable density with plasma discharge power (electron density) was reported [A. M. Daltrini, S. A. Moshkalev, T. J. Morgan, R. B. Piejak, and W. G. Graham, Appl. Phys. Lett. 92, 061504 (2008)]. Although the importance of the metastable atom and its density has been reported in a lot of literature, however, a basic physics behind the anomalous evolution of metastable density has not been clearly understood yet. In this study, we investigated a simple global model to elucidate the underlying physics of the anomalous evolution of argon metastable density with the electron density. Onmore » the basis of the proposed simple model, we reproduced the anomalous evolution of the metastable density and disclosed the detailed physics for the anomalous result. Drastic changes of dominant mechanisms for the population and depopulation processes of Ar metastable atoms with electron density, which take place even in relatively low electron density regime, is the clue to understand the result.« less

  17. Tensile stress-strain and work hardening behaviour of P9 steel for wrapper application in sodium cooled fast reactors

    NASA Astrophysics Data System (ADS)

    Christopher, J.; Choudhary, B. K.; Isaac Samuel, E.; Mathew, M. D.; Jayakumar, T.

    2012-01-01

    Tensile flow behaviour of P9 steel with different silicon content has been examined in the framework of Hollomon, Ludwik, Swift, Ludwigson and Voce relationships for a wide temperature range (300-873 K) at a strain rate of 1.3 × 10 -3 s -1. Ludwigson equation described true stress ( σ)-true plastic strain ( ɛ) data most accurately in the range 300-723 K. At high temperatures (773-873 K), Ludwigson equation reduces to Hollomon equation. The variations of instantaneous work hardening rate ( θ = dσ/ dɛ) and θσ with stress indicated two-stage work hardening behaviour. True stress-true plastic strain, flow parameters, θ vs. σ and θσ vs. σ with respect to temperature exhibited three distinct temperature regimes and displayed anomalous behaviour due to dynamic strain ageing at intermediate temperatures. Rapid decrease in flow stress and flow parameters, and rapid shift in θ- σ and θσ- σ towards lower stresses with increase in temperature indicated dominance of dynamic recovery at high temperatures.

  18. Low temperature magneto-morphological characterisation of coronene and the resolution of previously observed unexplained phenomena

    NASA Astrophysics Data System (ADS)

    Potticary, Jason; Boston, Rebecca; Vella-Zarb, Liana; Few, Alex; Bell, Christopher; Hall, Simon R.

    2016-12-01

    The polyaromatic hydrocarbon coronene has been the molecule of choice for understanding the physical properties of graphene for over a decade. The modelling of the latter by the former was considered to be valid, as since it was first synthesised in 1932, the physical behaviour of coronene has been determined extremely accurately. We recently discovered however, an unforeseen polymorph of coronene, which exists as an enantiotrope with the previously observed crystal structure. Using low-temperature magnetisation and crystallographic measurements, we show here for the first time that the electronic and magnetic properties of coronene depend directly on the temperature at which it is observed, with hysteretic behaviour exhibited between 300 K and 100 K. Furthermore we determine that this behaviour is a direct result of the appearance and disappearance of the newly-discovered polymorph during thermal cycling. Our results not only highlight the need for theoretical models of graphene to take into account this anomalous behaviour at low temperatures, but also explain puzzling experimental observations of coronene dating back over 40 years.

  19. Isospin breaking effects in the anomalous processes with vector mesons

    NASA Astrophysics Data System (ADS)

    Hashimoto, Michio

    1996-02-01

    We introduce isospin/ SU(3) breaking terms in the anomalous WP coupling in the hidden local symmetry scheme without affecting the low-energy theorem. It is shown that the predictions from these terms coincide successfully with all the experimental data of anomalous decays. It is also predicted that the decay widths of ϱ0 → π0γ and f → η‧γ are 114 ± 7 keV and 0.55 ± 0.055 keV, respectively.

  20. Hemispheric Asymmetry in Event Knowledge Activation During Incremental Language Comprehension: A Visual Half-Field ERP Study

    PubMed Central

    Metusalem, Ross; Kutas, Marta; Urbach, Thomas P.; Elman, Jeffrey L.

    2016-01-01

    During incremental language comprehension, the brain activates knowledge of described events, including knowledge elements that constitute semantic anomalies in their linguistic context. The present study investigates hemispheric asymmetries in this process, with the aim of advancing our understanding of the neural basis and functional properties of event knowledge activation during incremental comprehension. In a visual half-field event-related brain potential (ERP) experiment, participants read brief discourses in which the third sentence contained a word that was either highly expected, semantically anomalous but related to the described event, or semantically anomalous but unrelated to the described event. For both visual fields of target word presentation, semantically anomalous words elicited N400 ERP components of greater amplitude than did expected words. Crucially, event-related anomalous words elicited a reduced N400 relative to event-unrelated anomalous words only with left visual field/right hemisphere presentation. This result suggests that right hemisphere processes are critical to the activation of event knowledge elements that violate the linguistic context, and in doing so informs existing theories of hemispheric asymmetries in semantic processing during language comprehension. Additionally, this finding coincides with past research suggesting a crucial role for the right hemisphere in elaborative inference generation, raises interesting questions regarding hemispheric coordination in generating event-specific linguistic expectancies, and more generally highlights the possibility of functional dissociation between event knowledge activation for the generation of elaborative inferences and for linguistic expectancies. PMID:26878980

  1. Hemispheric asymmetry in event knowledge activation during incremental language comprehension: A visual half-field ERP study.

    PubMed

    Metusalem, Ross; Kutas, Marta; Urbach, Thomas P; Elman, Jeffrey L

    2016-04-01

    During incremental language comprehension, the brain activates knowledge of described events, including knowledge elements that constitute semantic anomalies in their linguistic context. The present study investigates hemispheric asymmetries in this process, with the aim of advancing our understanding of the neural basis and functional properties of event knowledge activation during incremental comprehension. In a visual half-field event-related brain potential (ERP) experiment, participants read brief discourses in which the third sentence contained a word that was either highly expected, semantically anomalous but related to the described event (Event-Related), or semantically anomalous but unrelated to the described event (Event-Unrelated). For both visual fields of target word presentation, semantically anomalous words elicited N400 ERP components of greater amplitude than did expected words. Crucially, Event-Related anomalous words elicited a reduced N400 relative to Event-Unrelated anomalous words only with left visual field/right hemisphere presentation. This result suggests that right hemisphere processes are critical to the activation of event knowledge elements that violate the linguistic context, and in doing so informs existing theories of hemispheric asymmetries in semantic processing during language comprehension. Additionally, this finding coincides with past research suggesting a crucial role for the right hemisphere in elaborative inference generation, raises interesting questions regarding hemispheric coordination in generating event-specific linguistic expectancies, and more generally highlights the possibility of functional dissociation of event knowledge activation for the generation of elaborative inferences and for linguistic expectancies. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Anomalous Diffusion Approximation of Risk Processes in Operational Risk of Non-Financial Corporations

    NASA Astrophysics Data System (ADS)

    Magdziarz, M.; Mista, P.; Weron, A.

    2007-05-01

    We introduce an approximation of the risk processes by anomalous diffusion. In the paper we consider the case, where the waiting times between successive occurrences of the claims belong to the domain of attraction of alpha -stable distribution. The relationship between the obtained approximation and the celebrated fractional diffusion equation is emphasised. We also establish upper bounds for the ruin probability in the considered model and give some numerical examples.

  3. Effect of anomalous tbW vertex on decay-lepton distributions in e+ e-® tt(bar) and CP-violating asymmetries

    NASA Astrophysics Data System (ADS)

    Rindani, Saurabh D.

    2000-06-01

    We obtain analytic expressions for the energy and polar-angle double differential distributions of a secondary lepton l+(l-) arising from the decay of t (tbar) in with an anomalous tbW decay vertex. We also obtain analytic expressions for the various differential cross-sections with the lepton energy integrated over. In this case, we find that the angular distributions of the secondary lepton do not depend on the anomalous coupling in the decay, regardless of possible anomalous couplings occurring in the production amplitude for . Our study includes the effect of longitudinal e- and e+ beam polarization. We also study the lepton energy and beam polarization dependence of certain CP-violating lepton angular asymmetries arising from an anomalous tbW decay vertex and compare them with the asymmetries arising due to CP-violation in the production process due to the top electric or weak dipole moment.

  4. [Developmental anatomy of anomalous structure and investigation of medicinal parts Sophora flavescens].

    PubMed

    Wang, Jun; Xie, Xiaomei; Peng, Huasheng

    2012-06-01

    To elucidate the composition structure of "annual rings" and the formation process of anomalous structures in Sophora flavescens, and further discuss the medicinal parts of S. flavescens. Based on investigation on S. flavescens in its producing areas, the morphology of root systems was observed, and the developmental anatomy of roots was researched. Creeping underground rhizomes of S. flavescen existed in some parts of the north place, there were many differences in appearance characters and microscopic features between these roots and rhizomes. Parenchyma cells in secondary xylem regained meristematic ability, became into anomalous cambia, and then developed into anomalous structures. "Annual rings" in transverse section of S. flavescens were not actually growth rings, they were made up of anomalous parenchyma girdle in secondary xylem and normal secondary structure. Roots are the medicinal parts of S. flavescens. This paper suggests that "annual rings" in the decoction pieces of S. flavescens should be called "annular structure".

  5. Anomalous diffusion and scaling in coupled stochastic processes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bel, Golan; Nemenman, Ilya

    2009-01-01

    Inspired by problems in biochemical kinetics, we study statistical properties of an overdamped Langevin processes with the friction coefficient depending on the state of a similar, unobserved, process. Integrating out the latter, we derive the Pocker-Planck the friction coefficient of the first depends on the state of the second. Integrating out the latter, we derive the Focker-Planck equation for the probability distribution of the former. This has the fonn of diffusion equation with time-dependent diffusion coefficient, resulting in an anomalous diffusion. The diffusion exponent can not be predicted using a simple scaling argument, and anomalous scaling appears as well. Themore » diffusion exponent of the Weiss-Havlin comb model is derived as a special case, and the same exponent holds even for weakly coupled processes. We compare our theoretical predictions with numerical simulations and find an excellent agreement. The findings caution against treating biochemical systems with unobserved dynamical degrees of freedom by means of standandard, diffusive Langevin descritpion.« less

  6. Identification of anomalous motion of thunderstorms using daily rainfall fields

    NASA Astrophysics Data System (ADS)

    Moral, Anna del; Llasat, María del Carmen; Rigo, Tomeu

    2017-03-01

    Most of the adverse weather phenomena in Catalonia (northeast Iberian Peninsula) are caused by convective events, which can produce heavy rains, large hailstones, strong winds, lightning and/or tornadoes. These thunderstorms usually have marked paths. However, their trajectories can vary sharply at any given time, completely changing direction from the path they have previously followed. Furthermore, some thunderstorms split or merge with each other, creating new formations with different behaviour. In order to identify the potentially anomalous movements that some thunderstorms make, this paper presents a two-step methodology using a database with 8 years of daily rainfall fields data for the Catalonia region (2008-2015). First, it classifies daily rainfall fields between days with "no rain", "non-potentially convective rain" and "potentially convective rain", based on daily accumulated precipitation and extension thresholds. Second, it categorises convective structures within rainfall fields and briefly identifies their main features, distinguishing whether there were any anomalous thunderstorm movements in each case. This methodology has been applied to the 2008-2015 period, and the main climatic features of convective and non-convective days were obtained. The methodology can be exported to other regions that do not have the necessary radar-based algorithms to detect convective cells, but where there is a good rain gauge network in place.

  7. Using virtual reality to investigate psychological processes and mechanisms associated with the onset and maintenance of psychosis: a systematic review.

    PubMed

    Valmaggia, Lucia R; Day, Fern; Rus-Calafell, Mar

    2016-07-01

    In the last decade researchers have embraced virtual reality to explore the psychological processes and mechanisms that are involved in the onset and maintenance of psychosis. A systematic review was conducted to synthesise the evidence of using virtual reality to investigate these mechanisms. Web of Science, PsycINFO, Embase, and Medline were searched. Reference lists of collected papers were also visually inspected to locate any relevant cited journal articles. In total 6001 articles were potentially eligible for inclusion; of these, 16 studies were included in the review. The review identified studies investigating the effect of interpersonal sensitivity, childhood bullying victimisation, physical assault, perceived ethnic discrimination, social defeat, population density and ethnic density on the real-time appraisal of VR social situations. Further studies demonstrated the potential of VR to investigate paranoid ideation, anomalous experiences, self-confidence, self-comparison, physiological activation and behavioural response. The reviewed studies suggest that VR can be used to investigate psychological processes and mechanisms associated with psychosis. Implications for further experimental research, as well as for assessment and clinical practise are discussed. The present review has been registered in the PROSPERO register: CRD42016038085.

  8. The behaviour of tributyl phosphate in an organic diluent

    NASA Astrophysics Data System (ADS)

    Leay, Laura; Tucker, Kate; Del Regno, Annalaura; Schroeder, Sven L. M.; Sharrad, Clint A.; Masters, Andrew J.

    2014-09-01

    Tributyl phosphate (TBP) is used as a complexing agent in the Plutonium Uranium Extraction (PUREX) liquid-liquid phase extraction process for recovering uranium and plutonium from spent nuclear reactor fuel. Here, we address the molecular and microstructure of the organic phases involved in the extraction process, using molecular dynamics to show that when TBP is mixed with a paraffinic diluent, the TBP self-assembles into a bi-continuous phase. The underlying self-association of TBP is driven by intermolecular interaction between its polar groups, resulting in butyl moieties radiating out into the organic solvent. Simulation predicts a TBP diffusion constant that is anomalously low compared to what might normally be expected for its size; experimental nuclear magnetic resonance (NMR) studies also indicate an extremely low diffusion constant, consistent with a molecular aggregation model. Simulation of TBP at an oil/water interface shows the formation of a bilayer system at low TBP concentrations. At higher concentrations, a bulk bi-continuous structure is observed linking to this surface bilayer. We suggest that this structure may be intimately connected with the surprisingly rapid kinetics of the interfacial mass transport of uranium and plutonium from the aqueous to the organic phase in the PUREX process.

  9. Intraoperative navigation-guided resection of anomalous transverse processes in patients with Bertolotti's syndrome

    PubMed Central

    Babu, Harish; Lagman, Carlito; Kim, Terrence T.; Grode, Marshall; Johnson, J. Patrick; Drazin, Doniel

    2017-01-01

    Background: Bertolotti's syndrome is characterized by enlargement of the transverse process at the most caudal lumbar vertebra with a pseudoarticulation between the transverse process and sacral ala. Here, we describe the use of intraoperative three-dimensional image-guided navigation in the resection of anomalous transverse processes in two patients with Bertolotti's syndrome. Case Descriptions: Two patients diagnosed with Bertolotti's syndrome who had undergone the above-mentioned procedure were identified. The patients were 17- and 38-years-old, and presented with severe, chronic low back pain that was resistant to conservative treatment. Imaging revealed lumbosacral transitional vertebrae at the level of L5-S1, which was consistent with Bertolotti's syndrome. Injections of the pseudoarticulations resulted in only temporary symptomatic relief. Thus, the patients subsequently underwent O-arm neuronavigational resection of the bony defects. Both patients experienced immediate pain resolution (documented on the postoperative notes) and remained asymptomatic 1 year later. Conclusion: Intraoperative three-dimensional imaging and navigation guidance facilitated the resection of anomalous transverse processes in two patients with Bertolotti's syndrome. Excellent outcomes were achieved in both patients. PMID:29026672

  10. Intraoperative navigation-guided resection of anomalous transverse processes in patients with Bertolotti's syndrome.

    PubMed

    Babu, Harish; Lagman, Carlito; Kim, Terrence T; Grode, Marshall; Johnson, J Patrick; Drazin, Doniel

    2017-01-01

    Bertolotti's syndrome is characterized by enlargement of the transverse process at the most caudal lumbar vertebra with a pseudoarticulation between the transverse process and sacral ala. Here, we describe the use of intraoperative three-dimensional image-guided navigation in the resection of anomalous transverse processes in two patients with Bertolotti's syndrome. Two patients diagnosed with Bertolotti's syndrome who had undergone the above-mentioned procedure were identified. The patients were 17- and 38-years-old, and presented with severe, chronic low back pain that was resistant to conservative treatment. Imaging revealed lumbosacral transitional vertebrae at the level of L5-S1, which was consistent with Bertolotti's syndrome. Injections of the pseudoarticulations resulted in only temporary symptomatic relief. Thus, the patients subsequently underwent O-arm neuronavigational resection of the bony defects. Both patients experienced immediate pain resolution (documented on the postoperative notes) and remained asymptomatic 1 year later. Intraoperative three-dimensional imaging and navigation guidance facilitated the resection of anomalous transverse processes in two patients with Bertolotti's syndrome. Excellent outcomes were achieved in both patients.

  11. Formation of anomalous eutectic in Ni-Sn alloy by laser cladding

    NASA Astrophysics Data System (ADS)

    Wang, Zhitai; Lin, Xin; Cao, Yongqing; Liu, Fencheng; Huang, Weidong

    2018-02-01

    Ni-Sn anomalous eutectic is obtained by single track laser cladding with the scanning velocity from 1 mm/s to 10 mm/s using the Ni-32.5 wt.%Sn eutectic powders. The microstructure of the cladding layer and the grain orientations of anomalous eutectic were investigated. It is found that the microstructure is transformed from primary α-Ni dendrites and the interdendritic (α-Ni + Ni3Sn) eutectic at the bottom of the cladding layer to α-Ni and β-Ni3Sn anomalous eutectic at the top of the cladding layer, whether for single layer or multilayer laser cladding. The EBSD maps and pole figures indicate that the spatially structure of α-Ni phase is discontinuous and the Ni3Sn phase is continuous in anomalous eutectic. The transformation from epitaxial growth columnar at bottom of cladding layer to free nucleation equiaxed at the top occurs, i.e., the columnar to equiaxed transition (CET) at the top of cladding layer during laser cladding processing leads to the generation of anomalous eutectic.

  12. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Papashvili, A G; Smetanin, S N; Doroshenko, M E

    A study of spectral and laser properties of the LiF : F{sub 2}{sup -} crystal at low temperatures has revealed an electronic – vibrational interaction of electrons of the F{sub 2}{sup -} centre with the local vibration of the centre, which occurs against the background of coupling between electrons of F{sub 2}{sup -} centres and lattice phonons. The interaction of electrons with the local vibration manifests itself in spectra in the form of narrow lines superimposed on wide electron – phonon lines that are due to the electron – lattice interaction. An anomalous behaviour of spectral LiF : F{sub 2}{supmore » -} laser lines is also found at liquid nitrogen temperature upon selective excitation; this behaviour is explained by the difference in the probabilities of the lattice and local interactions. (active media)« less

  13. Nonlinear control of high-frequency phonons in spider silk

    NASA Astrophysics Data System (ADS)

    Schneider, Dirk; Gomopoulos, Nikolaos; Koh, Cheong Y.; Papadopoulos, Periklis; Kremer, Friedrich; Thomas, Edwin L.; Fytas, George

    2016-10-01

    Spider dragline silk possesses superior mechanical properties compared with synthetic polymers with similar chemical structure due to its hierarchical structure comprised of partially crystalline oriented nanofibrils. To date, silk’s dynamic mechanical properties have been largely unexplored. Here we report an indirect hypersonic phononic bandgap and an anomalous dispersion of the acoustic-like branch from inelastic (Brillouin) light scattering experiments under varying applied elastic strains. We show the mechanical nonlinearity of the silk structure generates a unique region of negative group velocity, that together with the global (mechanical) anisotropy provides novel symmetry conditions for gap formation. The phononic bandgap and dispersion show strong nonlinear strain-dependent behaviour. Exploiting material nonlinearity along with tailored structural anisotropy could be a new design paradigm to access new types of dynamic behaviour.

  14. A permutation information theory tour through different interest rate maturities: the Libor case.

    PubMed

    Bariviera, Aurelio Fernández; Guercio, María Belén; Martinez, Lisana B; Rosso, Osvaldo A

    2015-12-13

    This paper analyses Libor interest rates for seven different maturities and referred to operations in British pounds, euros, Swiss francs and Japanese yen, during the period 2001-2015. The analysis is performed by means of two quantifiers derived from information theory: the permutation Shannon entropy and the permutation Fisher information measure. An anomalous behaviour in the Libor is detected in all currencies except euros during the years 2006-2012. The stochastic switch is more severe in one, two and three months maturities. Given the special mechanism of Libor setting, we conjecture that the behaviour could have been produced by the manipulation that was uncovered by financial authorities. We argue that our methodology is pertinent as a market overseeing instrument. © 2015 The Author(s).

  15. Effect of trap states and microstructure on charge carrier conduction mechanism through semicrystalline poly(vinyl alcohol) granular film

    NASA Astrophysics Data System (ADS)

    Das, A. K.; Bhowmik, R. N.; Meikap, A. K.

    2018-05-01

    We report a comprehensive study on hysteresis behaviour of current-voltage characteristic and impedance spectroscopy of granular semicrystalline poly(vinyl alcohol) (PVA) film. The charge carrier conduction mechanism and charge traps of granular PVA film by measuring and analyzing the temperature dependent current-voltage characteristic indicate a bi-stable electronic state in the film. A sharp transformation of charge carrier conduction mechanism from Poole-Frenkel emission to space charge limited current mechanism has been observed. An anomalous oscillatory behaviour of current has been observed due to electric pulse effect on the molecular chain of the polymer. Effect of microstructure on charge transport mechanism has been investigated from impedance spectroscopy analysis. An equivalent circuit model has been proposed to explain the result.

  16. Modeling Plasticity of Ni3Al-Based L12 Intermetallic Single Crystals-I. Anomalous Temperature Dependence of the Flow Behavior (Preprint)

    DTIC Science & Technology

    2006-07-01

    dislocation-loop expansion . The new model was used to simulate the thermally reversible flow behaviour for C-S type two-step deformation, and the results are...implemented into the finite element software ABAQUS through a User MATerial subroutine (UMAT). A tangent modulus method [48] was used for the time...locking under a dislocation loop- expansion configuration. This approach was motivated by modern understanding of dislocation mechanisms for Ni3Al

  17. Anomalous transport in the crowded world of biological cells

    NASA Astrophysics Data System (ADS)

    Höfling, Felix; Franosch, Thomas

    2013-04-01

    A ubiquitous observation in cell biology is that the diffusive motion of macromolecules and organelles is anomalous, and a description simply based on the conventional diffusion equation with diffusion constants measured in dilute solution fails. This is commonly attributed to macromolecular crowding in the interior of cells and in cellular membranes, summarizing their densely packed and heterogeneous structures. The most familiar phenomenon is a sublinear, power-law increase of the mean-square displacement (MSD) as a function of the lag time, but there are other manifestations like strongly reduced and time-dependent diffusion coefficients, persistent correlations in time, non-Gaussian distributions of spatial displacements, heterogeneous diffusion and a fraction of immobile particles. After a general introduction to the statistical description of slow, anomalous transport, we summarize some widely used theoretical models: Gaussian models like fractional Brownian motion and Langevin equations for visco-elastic media, the continuous-time random walk model, and the Lorentz model describing obstructed transport in a heterogeneous environment. Particular emphasis is put on the spatio-temporal properties of the transport in terms of two-point correlation functions, dynamic scaling behaviour, and how the models are distinguished by their propagators even if the MSDs are identical. Then, we review the theory underlying commonly applied experimental techniques in the presence of anomalous transport like single-particle tracking, fluorescence correlation spectroscopy (FCS) and fluorescence recovery after photobleaching (FRAP). We report on the large body of recent experimental evidence for anomalous transport in crowded biological media: in cyto- and nucleoplasm as well as in cellular membranes, complemented by in vitro experiments where a variety of model systems mimic physiological crowding conditions. Finally, computer simulations are discussed which play an important role in testing the theoretical models and corroborating the experimental findings. The review is completed by a synthesis of the theoretical and experimental progress identifying open questions for future investigation.

  18. Anomalous diffusion and long-range correlations in the score evolution of the game of cricket

    NASA Astrophysics Data System (ADS)

    Ribeiro, Haroldo V.; Mukherjee, Satyam; Zeng, Xiao Han T.

    2012-08-01

    We investigate the time evolution of the scores of the second most popular sport in the world: the game of cricket. By analyzing, event by event, the scores of more than 2000 matches, we point out that the score dynamics is an anomalous diffusive process. Our analysis reveals that the variance of the process is described by a power-law dependence with a superdiffusive exponent, that the scores are statistically self-similar following a universal Gaussian distribution, and that there are long-range correlations in the score evolution. We employ a generalized Langevin equation with a power-law correlated noise that describes all the empirical findings very well. These observations suggest that competition among agents may be a mechanism leading to anomalous diffusion and long-range correlation.

  19. Sonification of network traffic flow for monitoring and situational awareness

    PubMed Central

    2018-01-01

    Maintaining situational awareness of what is happening within a computer network is challenging, not only because the behaviour happens within machines, but also because data traffic speeds and volumes are beyond human ability to process. Visualisation techniques are widely used to present information about network traffic dynamics. Although they provide operators with an overall view and specific information about particular traffic or attacks on the network, they often still fail to represent the events in an understandable way. Also, because they require visual attention they are not well suited to continuous monitoring scenarios in which network administrators must carry out other tasks. Here we present SoNSTAR (Sonification of Networks for SiTuational AwaReness), a real-time sonification system for monitoring computer networks to support network administrators’ situational awareness. SoNSTAR provides an auditory representation of all the TCP/IP traffic within a network based on the different traffic flows between between network hosts. A user study showed that SoNSTAR raises situational awareness levels by enabling operators to understand network behaviour and with the benefit of lower workload demands (as measured by the NASA TLX method) than visual techniques. SoNSTAR identifies network traffic features by inspecting the status flags of TCP/IP packet headers. Combinations of these features define particular traffic events which are mapped to recorded sounds to generate a soundscape that represents the real-time status of the network traffic environment. The sequence, timing, and loudness of the different sounds allow the network to be monitored and anomalous behaviour to be detected without the need to continuously watch a monitor screen. PMID:29672543

  20. Sonification of network traffic flow for monitoring and situational awareness.

    PubMed

    Debashi, Mohamed; Vickers, Paul

    2018-01-01

    Maintaining situational awareness of what is happening within a computer network is challenging, not only because the behaviour happens within machines, but also because data traffic speeds and volumes are beyond human ability to process. Visualisation techniques are widely used to present information about network traffic dynamics. Although they provide operators with an overall view and specific information about particular traffic or attacks on the network, they often still fail to represent the events in an understandable way. Also, because they require visual attention they are not well suited to continuous monitoring scenarios in which network administrators must carry out other tasks. Here we present SoNSTAR (Sonification of Networks for SiTuational AwaReness), a real-time sonification system for monitoring computer networks to support network administrators' situational awareness. SoNSTAR provides an auditory representation of all the TCP/IP traffic within a network based on the different traffic flows between between network hosts. A user study showed that SoNSTAR raises situational awareness levels by enabling operators to understand network behaviour and with the benefit of lower workload demands (as measured by the NASA TLX method) than visual techniques. SoNSTAR identifies network traffic features by inspecting the status flags of TCP/IP packet headers. Combinations of these features define particular traffic events which are mapped to recorded sounds to generate a soundscape that represents the real-time status of the network traffic environment. The sequence, timing, and loudness of the different sounds allow the network to be monitored and anomalous behaviour to be detected without the need to continuously watch a monitor screen.

  1. Functional MRI of Conventional and Anomalous Metaphors in Mandarin Chinese

    ERIC Educational Resources Information Center

    Ahrens, Kathleen; Liu, Ho-Ling; Lee, Chia-Ying; Gong, Shu-Ping; Fang, Shin-Yi; Hsu, Yuan-Yu

    2007-01-01

    This study looks at whether conventional and anomalous metaphors are processed in different locations in the brain while being read when compared with a literal condition in Mandarin Chinese. We find that conventional metaphors differ from the literal condition with a slight amount of increased activation in the right inferior temporal gyrus. In…

  2. Superdiffusion revisited in view of collisionless reconnection

    NASA Astrophysics Data System (ADS)

    Treumann, R. A.; Baumjohann, W.

    2014-06-01

    The concept of diffusion in collisionless space plasmas like those near the magnetopause and in the geomagnetic tail during reconnection is reexamined making use of the division of particle orbits into waiting orbits and break-outs into ballistic motion lying at the bottom, for instance, of Lévy flights. The rms average displacement in this case increases with time, describing superdiffusion, though faster than classical, is still a weak process, being however strong enough to support fast reconnection. Referring to two kinds of numerical particle-in-cell simulations we determine the anomalous diffusion coefficient, the anomalous collision frequency on which the diffusion process is based, and construct a relation between the diffusion coefficients and the resistive scale. The anomalous collision frequency from electron pseudo-viscosity in reconnection turns out to be of the order of the lower-hybrid frequency with the latter providing a lower limit, thus making similar assumptions physically meaningful. Tentative though not completely justified use of the κ distribution yields κ ≈ 6 in the reconnection diffusion region and, for the anomalous diffusion coefficient, the order of several times Bohm diffusivity.

  3. Analysis of fcc metals fracture behaviour: Fracture behaviour of fcc metals: brittle/ductile behaviour criteria : with ab-initio, embedded atom and pseudopotential parameterization for Au, Ir and Al. analysis for Au, Ir and Al.

    NASA Astrophysics Data System (ADS)

    Gornostyrev, Yu. N.; Katsnelson, M. I.; Mryasov, Oleg N.; Freeman, A. J.; Trefilov, M. V.

    1998-03-01

    Theoretical analysis of the fracture behaviour of fcc Au, Ir and Al have been performed within various brittle/ductile criteria (BDC) with ab-initio, embedded atom (EAM), and pseudopotential parameterizations. We systematically examined several important aspects of the fracture behaviour: (i) dislocation structure, (ii) energetics of the cleavage decohesion and (iii) character of the interatomic interactions. Unit dislocation structures were analyzed within a two dimensional generalization of the Peierls-Nabarro model with restoring forces determined from ab-initio total energy calculations and found to be split with well defined highly mobile partials for all considered metals. We find from ab-initio and pseudopotential that in contrast with most of fcc metals, cleavage decohesion curve for Al appreciably differs from UBER relation. Finally, using ab-initio, EAM and pseudopotential parameterizations, we demonstrate that (i) Au (as a typical example of a ductile metal) is well described within existing BDC's, (ii) anomalous cleavage-like crack propagation of Ir is driven predominantly by it's high elastic modulus and (iii) Al is not described within BDC due to it's long-range interatomic interactions (and hence requires adjustments of the brittle/ductile criteria).

  4. CO2 emissions driven by wind are produced at global scale

    NASA Astrophysics Data System (ADS)

    Rosario Moya, M.; Sánchez-Cañete, Enrique P.; Kowalski, Andrew S.; Serrano-Ortiz, Penélope; López-Ballesteros, Ana; Oyonarte, Cecilio; Domingo, Francisco

    2017-04-01

    As an important tool for understanding and monitoring ecosystem dynamics at ecosystem level, the eddy covariance (EC) technique allows the assessment of the diurnal and seasonal variation of the net ecosystem exchange (NEE). Despite the high temporal resolution data, there are still many processes (in addition to photosynthesis and respiration) that, although they are being monitored, have been neglected. Only a few authors have studied anomalous CO2 emissions (non biological), and have related them to soil ventilation, photodegradation or geochemical processes. The aims of this study are: 1) to identify anomalous daytime CO2 emissions in different ecosystems distributed around the world, 2) to determine the meteorological variables that influence these emissions, and 3) to explore the potential processes which can be involved. We have studied EC data together with other meteorological ancillary variables obtained from the FLUXNET database and have found more than 50 sites with anomalous CO2 emissions in different ecosystem types such as grasslands, croplands or savannas. Data were filtered according to the FLUXNET quality control flags (only data with maximum quality were used, i.e. control flag equal to 0) and daytime (shortwave radiation incoming > 50 W m-2). Partial Spearman correlation analyses were performed between NEE and ancillary data: air temperature, vapour pressure deficit, soil temperature, precipitation, atmospheric pressure, soil water content, incoming photosynthetic photon flux density, friction velocity and net radiation. When necessary, ancillary variables were gap-filled using the MDS method (Reichstein et al. 2005). Preliminary results showed strong and highly significant correlations between friction velocity and anomalous CO2 emissions, suggesting that these emissions were mainly produced by ventilation events. Anomalous CO2 emissions were found mainly in arid ecosystems and sites with hot and dry summers. We suggest that anomalous CO2 emissions occur globally and therefore, their contribution to the global NEE requires further investigation in order to better understand its drivers.

  5. Comparisons of anomalous and collisional radial transport with a continuum kinetic edge code

    NASA Astrophysics Data System (ADS)

    Bodi, K.; Krasheninnikov, S.; Cohen, R.; Rognlien, T.

    2009-05-01

    Modeling of anomalous (turbulence-driven) radial transport in controlled-fusion plasmas is necessary for long-time transport simulations. Here the focus is continuum kinetic edge codes such as the (2-D, 2-V) transport version of TEMPEST, NEO, and the code being developed by the Edge Simulation Laboratory, but the model also has wider application. Our previously developed anomalous diagonal transport matrix model with velocity-dependent convection and diffusion coefficients allows contact with typical fluid transport models (e.g., UEDGE). Results are presented that combine the anomalous transport model and collisional transport owing to ion drift orbits utilizing a Krook collision operator that conserves density and energy. Comparison is made of the relative magnitudes and possible synergistic effects of the two processes for typical tokamak device parameters.

  6. Evolving optimised decision rules for intrusion detection using particle swarm paradigm

    NASA Astrophysics Data System (ADS)

    Sivatha Sindhu, Siva S.; Geetha, S.; Kannan, A.

    2012-12-01

    The aim of this article is to construct a practical intrusion detection system (IDS) that properly analyses the statistics of network traffic pattern and classify them as normal or anomalous class. The objective of this article is to prove that the choice of effective network traffic features and a proficient machine-learning paradigm enhances the detection accuracy of IDS. In this article, a rule-based approach with a family of six decision tree classifiers, namely Decision Stump, C4.5, Naive Baye's Tree, Random Forest, Random Tree and Representative Tree model to perform the detection of anomalous network pattern is introduced. In particular, the proposed swarm optimisation-based approach selects instances that compose training set and optimised decision tree operate over this trained set producing classification rules with improved coverage, classification capability and generalisation ability. Experiment with the Knowledge Discovery and Data mining (KDD) data set which have information on traffic pattern, during normal and intrusive behaviour shows that the proposed algorithm produces optimised decision rules and outperforms other machine-learning algorithm.

  7. Anomalous Variation in GPS TEC, Land and Ocean Parameters Prior to 3 Earthquakes

    NASA Astrophysics Data System (ADS)

    Yadav, Kunvar; Karia, Sheetal P.; Pathak, Kamlesh N.

    2016-02-01

    The present study reports the analysis of GPS TEC prior to 3 earthquakes ( M > 6.0). The earthquakes are: (1) Loyalty Island (22°36'S, 170°54'E) on 19 January 2009 ( M = 6.6), (2) Samoa Island (15°29'S, 172°5'W) on 30 August 2009 ( M = 6.6), and (3) Tohoku (38°19'N, 142°22'E) on 11 March 2011 ( M = 9.0). In an effort to search for a precursory signature we analysed the land and ocean parameters prior to the earthquakes, namely SLHF (Land) and SST (Ocean). The GPS TEC data indicate an anomalous behaviour from 1-13 days prior to earthquakes. The main purpose of this study was to explore and demonstrate the possibility of any changes in TEC, SST, and SLHF before, during and after the earthquakes which occurred near or beneath an ocean. This study may lead to better understanding of response of land, ocean, and ionosphere parameters prior to seismic activities.

  8. Report of reprocessing of reflection seismic profile X-5 Waste Isolation Pilot Plant site, Eddy County, New Mexico

    USGS Publications Warehouse

    Miller, John J.

    1983-01-01

    Seismic reflection profile X-5 exhibits a 7,700 ft long anomalous zone of poor quality to nonexistent reflections between shotpoints 100 and 170, compared to the high-quality, flat-lying, coherent reflections on either side. Results from drill holes in the area suggest 'layer cake' geology with no detectable abnormalities such as faults present. In an attempt to determine whether the anomalous zone of the seismic profile is an artifact or actually indicates a geologic condition, the data were extensively reprocessed using state-of-the-art processing techniques and the following conclusions were made: 1. The field-recorded data in the anomalous zone are of poor quality due to surface conditions and recording parameters used. 2. Reprocessing shows reflectors throughout the anomalous zone at all levels. However, it cannot prove that the reflectors are continuous throughout the anomalous zone. 3. Significant improvement in data quality may be achieved if the line is reshot using carefully determined recording parameters.

  9. Anomalous Origin of the Right Vertebral Artery: Incidence and Significance.

    PubMed

    Maiti, Tanmoy Kumar; Konar, Subhas Kanti; Bir, Shyamal; Nanda, Anil; Cuellar, Hugo

    2016-05-01

    Detailed knowledge about anatomic variations of the aortic arch and its multiple branches is extremely important to endovascular and diagnostic radiologists. It is often hypothesized that anomalous origin and distribution of large aortic vessels may alter the cerebral hemodynamics and potentially lead to a vascular pathology. In this article, we describe a case of anomalous origin of the right vertebral artery, which was detected during an intervention. We further reviewed the available literature of anomalous origin of the right vertebral artery. The probable embryologic development and clinical significance are discussed. The incidence of anomalous origin of a vertebral artery seems to be underestimated in recent literature. A careful review of the literature shows more than 100 such cases. The right vertebral artery can arise from the aortic arch or one of its branches. Dual origin of the vertebral artery is not uncommon. The embryologic developmental hypotheses are contradictory and complex. Anomalous origin of the right vertebral artery may not be the sole reason behind a disease process. However, it can certainly lead to a misdiagnosis during diagnostic vascular studies. Detailed information is essential for any surgery or endovascular intervention in this location. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. Chronic Mild Stress (CMS) in Mice: Of Anhedonia, ‘Anomalous Anxiolysis’ and Activity

    PubMed Central

    Schweizer, Martin C.; Henniger, Markus S. H.; Sillaber, Inge

    2009-01-01

    Background In a substantial proportion of depressed patients, stressful life events play a role in triggering the evolution of the illness. Exposure to stress has effects on different levels in laboratory animals as well and for the rat it has been shown that chronic mild stress (CMS) can cause antidepressant-reversible depressive-like effects. The adoption of the model to the mouse seems to be problematic, depending on the strain used and behavioural endpoint defined. Our aim was to evaluate the applicability of CMS to mice in order to induce behavioural alterations suggested to reflect depression-like symptoms. Methodology/Principal Findings A weekly CMS protocol was applied to male mice of different mouse strains (D2Ola, BL/6J and BL/6N) and its impact on stress-sensitive behavioural measures (anhedonia-, anxiety- and depression-related parameters) and body weight was assessed. Overnight illumination as commonly used stressor in CMS protocols was particularly investigated in terms of its effect on general activity and subsequently derived saccharin intake. CMS application yielded strain-dependent behavioural and physiological responses including ‘paradox’ anxiolytic-like effects. Overnight illumination was found to be sufficient to mimic anhedonic-like behaviour in BL/6J mice when being applied as sole stressor. Conclusions/Significance The CMS procedure induced some behavioural changes that are compatible with the common expectations, i.e. ‘anhedonic’ behaviour, but in parallel behavioural alterations were observed which would be described as ‘anomalous’ (e.g. decreased anxiety). The results suggest that a shift in the pattern of circadian activity has a particular high impact on the anhedonic profile. Changes in activity in response to novelty seem to drive the ‘anomalous’ behavioural alterations as well. PMID:19177164

  11. Simultaneous organic nitrogen and sulfate removal in an anaerobic GAC fluidised bed reactor.

    PubMed

    Fdz-Polanco, F; Fdz-Polanco, M; Fernandez, N; Urueña, M A; García, P A; Villaverde, S

    2001-01-01

    A granular activated carbon (GAC) anaerobic fluidised bed reactor treating vinasse from an ethanol distillery of sugar beet molasses was operated for 250 days under three different organic loading rates. The reactor showed good performance in terms of organic matter removal and methane production but an anomalous behaviour in terms of unusual high concentrations of molecular nitrogen and low concentration of hydrogen sulphide in the biogas. The analysis of the different nitrogenous and sulphur compounds and the mass balances of these species in the liquid and gas phases clearly indicated an uncommon evolution of nitrogen and sulphur in the reactor. Up to 55% of the TKN and up to 80% of the sulphur disappear in the liquid phase. This is the opposite to any previously reported results in the bibliography. The new postulated anaerobic process of ammonia and sulphate removal seems to follow the mechanism: SO4 = +2 NH4+-->S + N2 + 4H2O (delta G degree = -47.8 kJ/mol).

  12. Temperature-regulated guest admission and release in microporous materials

    DOE PAGES

    Li, Gang; Shang, Jin; Gu, Qinfen; ...

    2017-06-09

    While it has long been known that some highly adsorbing microporous materials suddenly become inaccessible to guest molecules below certain temperatures, previous attempts to explain this phenomenon have failed. Here we show that this anomalous sorption behaviour is a temperature-regulated guest admission process, where the pore-keeping group’s thermal fluctuations are influenced by interactions with guest molecules. A physical model is presented to explain the atomic-level chemistry and structure of these thermally regulated micropores, which is crucial to systematic engineering of new functional materials such as tunable molecular sieves, gated membranes and controlled-release nanocontainers. The model was validated experimentally with Hmore » 2, N 2, Ar and CH 4 on three classes of microporous materials: trapdoor zeolites, supramolecular host calixarenes and metal-organic frameworks. We also demonstrate how temperature can be exploited to achieve appreciable hydrogen and methane storage in such materials without sustained pressure. Our findings also open new avenues for gas sensing and isotope separation.« less

  13. Tunable-φ Josephson junction with a quantum anomalous Hall insulator

    NASA Astrophysics Data System (ADS)

    Sakurai, Keimei; Ikegaya, Satoshi; Asano, Yasuhiro

    2017-12-01

    We theoretically study the Josephson current in a superconductor/quantum anomalous Hall insulator/superconductor junction by using the lattice Green function technique. When an in-plane external Zeeman field is applied to the quantum anomalous Hall insulator, the Josephson current J flows without a phase difference across the junction θ . The phase shift φ appearing in the current-phase relationship J ∝sin(θ -φ ) is proportional to the amplitude of Zeeman fields and depends on the direction of Zeeman fields. A phenomenological analysis of the Andreev reflection processes explains the physical origin of φ . In a quantum anomalous Hall insulator, time-reversal symmetry and mirror-reflection symmetry are broken simultaneously. However, magnetic mirror-reflection symmetry is preserved. Such characteristic symmetry properties enable us to have a tunable φ junction with a quantum Hall insulator.

  14. Process Contributions to Cool Java SST Anomalies at the Onset of Positive Indian Ocean Dipole Events

    NASA Astrophysics Data System (ADS)

    Delman, A. S.; McClean, J.; Sprintall, J.; Talley, L. D.

    2016-12-01

    The seasonal upwelling region along the south coast of Java is the first area to exhibit the negative SST anomalies associated with positive Indian Ocean Dipole (pIOD) events. The seasonal cooling in austral winter is driven by local wind forcing; however, recent observational studies have suggested that the anomalous Java cooling that starts during May-July of pIOD years is driven largely by intraseasonal wind variability along the equator, which forces upwelling Kelvin waves that propagate to the coast of Java. Using observations and an eddy-active ocean GCM simulation, the impacts of local wind stress and remotely-forced Kelvin waves are assessed and compared to the effects of mesoscale eddies and outflows from nearby Lombok Strait. A Kelvin wave coefficient computed from altimetry data shows anomalous levels of upwelling Kelvin wave activity during May-July of all pIOD years, indicating that Kelvin waves are an important and perhaps necessary precondition for pIOD events. Correlation analyses also suggest that flows through Lombok Strait and winds along the Indonesian Throughflow may be influential, though their impacts are more difficult to isolate. Composite temperature budgets from the ocean GCM indicate that advection and diabatic vertical mixing are the primary mechanisms for anomalous mixed layer cooling south of Java. The advection term is further decomposed by linearly regressing model velocity and temperature anomalies onto indices representing each process. According to this process decomposition, the local wind stress and Kelvin waves together account for most of the anomalous advective cooling, though the anomalous cooling effect of local wind stress may be overestimated in the model due to wind and stratification biases. The process decomposition also shows a very modest warming effect from mesoscale eddies. These results demonstrate both the IOD's resemblance to ENSO in the importance of Kelvin waves for its evolution, and notable differences from ENSO that arise from the complex interplay of local winds, planetary waves, stratification, eddies, and topography in the Indonesian region.

  15. Hydrologic processes in China and their association with summer precipitation anomalies

    NASA Astrophysics Data System (ADS)

    Chen, M.; Pollard, D.; Barron, E. J.

    2005-01-01

    A climate version of MM5 is applied to study hydrologic processes in China and their association with precipitation anomalies in 1980 and 1985, which are two anomalous years with opposite signs of summer precipitation anomalies. The study reveals that anomalous atmospheric moisture transport due to synoptic scale circulation was primarily responsible for initiating the anomalous wet (dry) summer in south-central China and dry (wet) summer in northeastern China in 1980 (1985). The recycling ratio (defined as contribution of local evaporation to total precipitation) ranges from less than 4% in northwestern China to more than 30% in south-central China at 1000 km space scale. Higher (lower) values of recycling ratio correspond to drier (wetter) summers in south-central China and northeastern China. However, the opposite is true in northwestern China. The recycling ratio reflects feedback among hydrologic components over both land and atmosphere. In northwestern China, these feedbacks will further sustain drought events that are triggered by anomalous synoptic scale disturbances, and turn them into prolonged and possibly perpetual phenomenon. However, in south-central China and northeastern China, these feedbacks help reducing severity of drought. The large differences in recycling ratio between the dry and wet years of 1980 and 1985 are indicative of powerful feedback between hydrologic and climatic processes, and imply that surface-atmosphere interaction in China is highly sensitive to climatic perturbation.

  16. The physics of confined flow and its application to water leaks, water permeation and water nanoflows: a review.

    PubMed

    Lei, Wenwen; Rigozzi, Michelle K; McKenzie, David R

    2016-02-01

    This review assesses the current state of understanding of the calculation of the rate of flow of gases, vapours and liquids confined in channels, in porous media and in permeable materials with an emphasis on the flow of water and its vapour. One motivation is to investigate the relation between the permeation rate of moisture and that of a noncondensable test gas such as helium, another is to assist in unifying theory and experiment across disparate fields. Available theories of single component ideal gas flows in channels of defined geometry (cylindrical, rectangular and elliptical) are described and their predictions compared with measurement over a wide range of conditions defined by the Knudsen number. Theory for two phase flows is assembled in order to understand the behaviour of four standard water leak configurations: vapour, slug, Washburn and liquid flow, distinguished by the number and location of phase boundaries (menisci). Air may or may not be present as a background gas. Slip length is an important parameter that greatly affects leak rates. Measurements of water vapour flows confirm that water vapour shows ideal gas behaviour. Results on carbon nanotubes show that smooth walls may lead to anomalously high slip lengths arising from the properties of 'confined' water. In porous media, behaviour can be matched to the four standard leaks. Traditional membrane permeation models consider that the permeant dissolves, diffuses and evaporates at the outlet side, ideas we align with those from channel flow. Recent results on graphite oxide membranes show examples where helium which does not permeate while at the same time moisture is almost unimpeded, again a result of confined water. We conclude that while there is no a priori relation between a noncondensable gas flow and a moisture flow, measurements using helium will give results within two orders of magnitude of the moisture flow rate, except in the case where there is anomalous slip or confined water, when moisture specific measurements are essential.

  17. Dilational processes accompanying earthquakes in the Long Valley Caldera

    USGS Publications Warehouse

    Dreger, Douglas S.; Tkalcic, Hrvoje; Johnston, M.

    2000-01-01

    Regional distance seismic moment tensor determinations and broadband waveforms of moment magnitude 4.6 to 4.9 earthquakes from a November 1997 Long Valley Caldera swarm, during an inflation episode, display evidence of anomalous seismic radiation characterized by non-double couple (NDC) moment tensors with significant volumetric components. Observed coseismic dilation suggests that hydrothermal or magmatic processes are directly triggering some of the seismicity in the region. Similarity in the NDC solutions implies a common source process, and the anomalous events may have been triggered by net fault-normal stress reduction due to high-pressure fluid injection or pressurization of fluid-saturated faults due to magmatic heating.

  18. Fickian dispersion is anomalous

    DOE PAGES

    Cushman, John H.; O’Malley, Dan

    2015-06-22

    The thesis put forward here is that the occurrence of Fickian dispersion in geophysical settings is a rare event and consequently should be labeled as anomalous. What people classically call anomalous is really the norm. In a Lagrangian setting, a process with mean square displacement which is proportional to time is generally labeled as Fickian dispersion. With a number of counter examples we show why this definition is fraught with difficulty. In a related discussion, we show an infinite second moment does not necessarily imply the process is super dispersive. By employing a rigorous mathematical definition of Fickian dispersion wemore » illustrate why it is so hard to find a Fickian process. We go on to employ a number of renormalization group approaches to classify non-Fickian dispersive behavior. Scaling laws for the probability density function for a dispersive process, the distribution for the first passage times, the mean first passage time, and the finite-size Lyapunov exponent are presented for fixed points of both deterministic and stochastic renormalization group operators. The fixed points of the renormalization group operators are p-self-similar processes. A generalized renormalization group operator is introduced whose fixed points form a set of generalized self-similar processes. Finally, power-law clocks are introduced to examine multi-scaling behavior. Several examples of these ideas are presented and discussed.« less

  19. S193: another non-eclipsing SW Sex star

    NASA Astrophysics Data System (ADS)

    Martínez-Pais, I. G.; Rodríguez-Gil, P.; Casares, J.

    1999-05-01

    We present time-resolved optical spectroscopy of the cataclysmic variable S193. The emission lines are remarkably similar to those of V795 Her and exhibit high-velocity S-waves and complex absorptions that are modulated with the orbital period. Evidence for transient anomalous spectral features is seen during the first two nights of our run. We propose that S193 and V795 Her are non-eclipsing SW Sex stars. Finally, we show that the `disc overflow' model fails to explain the Balmer line orbital behaviour in these low-inclination systems.

  20. An analysis of superluminal propagation becoming subluminal in highly dispersive media

    NASA Astrophysics Data System (ADS)

    Nanda, L.

    2018-05-01

    In this article the time-moments of the Poynting vector associated with an electromagnetic pulse are used to characterize the traversal time and the pulse width as the pulse propagates through highly dispersive media. The behaviour of these quantities with propagation distance is analyzed in two physical cases: Lorentz absorptive medium, and Raman gain doublet amplifying medium. It is found that the superluminal pulse propagation in these two cases with anomalous dispersion is always accompanied by pulse compression and eventually the pulse becomes subluminal with increasing distance of propagation.

  1. Why rainfall response to El Niño over Maritime Continent is weaker and non-uniform in boreal winter than in boreal summer

    NASA Astrophysics Data System (ADS)

    Jiang, Leishan; Li, Tim

    2017-11-01

    Why rainfall response to El Niño is uniform and stronger over the Maritime Continent (MC) during El Niño developing summer and fall but is weaker and non-uniform during El Niño mature winter is investigated through the diagnosis of anomalous large-scale circulation patterns and a local moisture budget analysis. It is found that when anomalous Walker cells across the equatorial Pacific and Indian Ocean are strengthened toward El Niño mature winter, a low-level ascending motion anomaly starts to develop over western MC in northern fall due to topographic lifting (near Sumatra) and anomalous wind convergence (near west Kalimantan). Easterly anomalies, as a part of an anomalous anticyclone in South China Sea (SCS) that is developed during El Niño and a part of the south-easterly from Java Sea associated with anomalous Walker Circulation, bump into the mountain ridge of Sumatra and induce ascending motion anomalies near Sumatra. Meanwhile, the anomalous north-easterly in the southern flank of the anomalous anticyclone over SCS and south-easterly over Java Sea converge into west Kalimantan, leading to ascending motion there. The anomalous ascending motion tend to advect mean moisture upward to moisten lower troposphere in situ. This low-level moistening eventually sets up a convectively unstable stratification and induces a positive precipitation anomaly in the western MC. How the mechanism discussed here is relevant to previous hypotheses and how processes during El Niño might differ during La Niña are discussed.

  2. Variable-order fractional MSD function to describe the evolution of protein lateral diffusion ability in cell membranes

    NASA Astrophysics Data System (ADS)

    Yin, Deshun; Qu, Pengfei

    2018-02-01

    Protein lateral diffusion is considered anomalous in the plasma membrane. And this diffusion is related to membrane microstructure. In order to better describe the property of protein lateral diffusion and find out the inner relationship between protein lateral diffusion and membrane microstructure, this article applies variable-order fractional mean square displacement (f-MSD) function for characterizing the anomalous diffusion. It is found that the variable order can reflect the evolution of diffusion ability. The results of numerical simulation demonstrate variable-order f-MSD function can predict the tendency of anomalous diffusion during the process of confined diffusion. It is also noted that protein lateral diffusion ability during the processes of confined and hop diffusion can be split into three parts. In addition, the comparative analyses reveal that the variable order is related to the confinement-domain size and microstructure of compartment boundary too.

  3. Constraining anomalous Higgs boson couplings to the heavy-flavor fermions using matrix element techniques

    NASA Astrophysics Data System (ADS)

    Gritsan, Andrei V.; Röntsch, Raoul; Schulze, Markus; Xiao, Meng

    2016-09-01

    In this paper, we investigate anomalous interactions of the Higgs boson with heavy fermions, employing shapes of kinematic distributions. We study the processes p p →t t ¯+H , b b ¯+H , t q +H , and p p →H →τ+τ- and present applications of event generation, reweighting techniques for fast simulation of anomalous couplings, as well as matrix element techniques for optimal sensitivity. We extend the matrix element likelihood approach (MELA) technique, which proved to be a powerful matrix element tool for Higgs boson discovery and characterization during Run I of the LHC, and implement all analysis tools in the JHU generator framework. A next-to-leading-order QCD description of the p p →t t ¯+H process allows us to investigate the performance of the MELA in the presence of extra radiation. Finally, projections for LHC measurements through the end of Run III are presented.

  4. The massive soft anomalous dimension matrix at two loops

    NASA Astrophysics Data System (ADS)

    Mitov, Alexander; Sterman, George; Sung, Ilmo

    2009-05-01

    We study two-loop anomalous dimension matrices in QCD and related gauge theories for products of Wilson lines coupled at a point. We verify by an analysis in Euclidean space that the contributions to these matrices from diagrams that link three massive Wilson lines do not vanish in general. We show, however, that for two-to-two processes the two-loop anomalous dimension matrix is diagonal in the same color-exchange basis as the one-loop matrix for arbitrary masses at absolute threshold and for scattering at 90 degrees in the center of mass. This result is important for applications of threshold resummation in heavy quark production.

  5. Anomalous law of cooling

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lapas, Luciano C., E-mail: luciano.lapas@unila.edu.br; Ferreira, Rogelma M. S., E-mail: rogelma.maria@gmail.com; Rubí, J. Miguel, E-mail: mrubi@ub.edu

    2015-03-14

    We analyze the temperature relaxation phenomena of systems in contact with a thermal reservoir that undergoes a non-Markovian diffusion process. From a generalized Langevin equation, we show that the temperature is governed by a law of cooling of the Newton’s law type in which the relaxation time depends on the velocity autocorrelation and is then characterized by the memory function. The analysis of the temperature decay reveals the existence of an anomalous cooling in which the temperature may oscillate. Despite this anomalous behavior, we show that the variation of entropy remains always positive in accordance with the second law ofmore » thermodynamics.« less

  6. Anisotropic anomalous Hall effect in triangular itinerant ferromagnet Fe3GeTe2

    NASA Astrophysics Data System (ADS)

    Wang, Yihao; Xian, Cong; Wang, Jian; Liu, Bingjie; Ling, Langsheng; Zhang, Lei; Cao, Liang; Qu, Zhe; Xiong, Yimin

    2017-10-01

    Magnetic frustrated materials are of great interest for their novel spin-dependent transport properties. We report an anisotropic anomalous Hall effect in the triangular itinerant ferromagnet Fe3GeTe2 . When the current flows along the a b plane, Fe3GeTe2 exhibits the conventional anomalous Hall effect below the Curie temperature Tc, which can be depicted by Karplus-Luttinger theory. On the other hand, the topological Hall effect shows up below Tc with current along the c axis. The enhancement of Hall resistivity can be attributed to the chiral effect during the spin-flop process.

  7. Continuation-like semantics for modeling structural process anomalies

    PubMed Central

    2012-01-01

    Background Biomedical ontologies usually encode knowledge that applies always or at least most of the time, that is in normal circumstances. But for some applications like phenotype ontologies it is becoming increasingly important to represent information about aberrations from a norm. These aberrations may be modifications of physiological structures, but also modifications of biological processes. Methods To facilitate precise definitions of process-related phenotypes, such as delayed eruption of the primary teeth or disrupted ocular pursuit movements, I introduce a modeling approach that draws inspiration from the use of continuations in the analysis of programming languages and apply a similar idea to ontological modeling. This approach characterises processes by describing their outcome up to a certain point and the way they will continue in the canonical case. Definitions of process types are then given in terms of their continuations and anomalous phenotypes are defined by their differences to the canonical definitions. Results The resulting model is capable of accurately representing structural process anomalies. It allows distinguishing between different anomaly kinds (delays, interruptions), gives identity criteria for interrupted processes, and explains why normal and anomalous process instances can be subsumed under a common type, thus establishing the connection between canonical and anomalous process-related phenotypes. Conclusion This paper shows how to to give semantically rich definitions of process-related phenotypes. These allow to expand the application areas of phenotype ontologies beyond literature annotation and establishment of genotype-phenotype associations to the detection of anomalies in suitably encoded datasets. PMID:23046705

  8. Relation of tolerance of ambiguity to global and specific paranormal experience.

    PubMed

    Houran, J; Williams, C

    1998-12-01

    We examined the relationship of tolerance of ambiguity to severe global factors and specific types of anomalous or paranormal experience. 107 undergraduate students completed MacDonald's 1970 AT-20 and the Anomalous Experiences Inventory of Kumar, Pekala, and Gallagher. Scores on the five subscales of the Anomalous Experiences Inventory correlated differently with tolerance of ambiguity. Global paranormal beliefs, abilities, experiences, and drug use were positively associated with tolerance of ambiguity, whereas a fear of paranormal experience showed a negative relation. The specific types of anomalous experiences that correlated with tolerance of ambiguity often involved internal or physiological experience, e.g., precognitive dreams, memories of reincarnation, visual apparitions, and vestibular alterations. We generally found no effects of age of sex. These results are consistent with the idea that some paranormal experiences are misattributions of internal experience to external ('paranormal') sources, a process analogous to mechanisms underpinning delusions and hallucinations.

  9. Diffusion control for a tempered anomalous diffusion system using fractional-order PI controllers.

    PubMed

    Juan Chen; Zhuang, Bo; Chen, YangQuan; Cui, Baotong

    2017-05-09

    This paper is concerned with diffusion control problem of a tempered anomalous diffusion system based on fractional-order PI controllers. The contribution of this paper is to introduce fractional-order PI controllers into the tempered anomalous diffusion system for mobile actuators motion and spraying control. For the proposed control force, convergence analysis of the system described by mobile actuator dynamical equations is presented based on Lyapunov stability arguments. Moreover, a new Centroidal Voronoi Tessellation (CVT) algorithm based on fractional-order PI controllers, henceforth called FOPI-based CVT algorithm, is provided together with a modified simulation platform called Fractional-Order Diffusion Mobile Actuator-Sensor 2-Dimension Fractional-Order Proportional Integral (FO-Diff-MAS2D-FOPI). Finally, extensive numerical simulations for the tempered anomalous diffusion process are presented to verify the effectiveness of our proposed fractional-order PI controllers. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  10. Combinatorial semantics strengthens angular-anterior temporal coupling.

    PubMed

    Molinaro, Nicola; Paz-Alonso, Pedro M; Duñabeitia, Jon Andoni; Carreiras, Manuel

    2015-04-01

    The human semantic combinatorial system allows us to create a wide number of new meanings from a finite number of existing representations. The present study investigates the neural dynamics underlying the semantic processing of different conceptual constructions based on predictions from previous neuroanatomical models of the semantic processing network. In two experiments, participants read sentences for comprehension containing noun-adjective pairs in three different conditions: prototypical (Redundant), nonsense (Anomalous) and low-typical but composable (Contrastive). In Experiment 1 we examined the processing costs associated to reading these sentences and found a processing dissociation between Anomalous and Contrastive word pairs, compared to prototypical (Redundant) stimuli. In Experiment 2, functional connectivity results showed strong co-activation across conditions between inferior frontal gyrus (IFG) and posterior middle temporal gyrus (MTG), as well as between these two regions and middle frontal gyrus (MFG), anterior temporal cortex (ATC) and fusiform gyrus (FG), consistent with previous neuroanatomical models. Importantly, processing of low-typical (but composable) meanings relative to prototypical and anomalous constructions was associated with a stronger positive coupling between ATC and angular gyrus (AG). Our results underscore the critical role of IFG-MTG co-activation during semantic processing and how other relevant nodes within the semantic processing network come into play to handle visual-orthographic information, to maintain multiple lexical-semantic representations in working memory and to combine existing representations while creatively constructing meaning. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Indications of noncontinuous PVT-behaviour of H2O at high P-T conditions

    NASA Astrophysics Data System (ADS)

    Mirwald, P. W.

    2003-04-01

    The understanding of the properties of H_2O is still limited despite its apparently tri-vial chemical composition and unique importance. In contrast to the complex system of ice and amorphous water being revealed at low temperature and high pressure (1) the P-T field of water is still relatively unexplored. The steam tables (2) suggest an apparently continuous volume behaviour over the covered P-T range. However, a number of diffraction experiments in the ambient temperature range at high pressure indicate changes in the co-ordination of the H_2O molecules (e.g. 3). A re-examination of literature data on the melting of ice I--VII and the PVT-behaviour of water the range of 20 to 300^oC and 1 to 20 kbar has recently been conducted (4). The detailed evaluation indicated anomalous behaviour of water at some 2--4 and 7--8 Kb and thus three different regimes of steam behaviour. Own preliminary data from compression experiments at 25^oC (5) confirm these two anomalies. In addition the steam data indicate non-continuous compression behaviour also towards higher temperatures (4). Again three different areas of different PVT behaviour of steam may be distinguished divided by two anomaly boundaries of shallow dP/dT slope at some 10 and 20 kb. However, the correlation between the topologies at low and high temperatures is not clear. Solution data at high P-T conditions e.g. on corundum (6) and on quartz (7) show a significant discontinuous behaviour if Δsol./ΔP is plotted vs. pressure. So, at 700^oC discontinuous solubility changes are encountered at 10 kbar and at 19 kbar what is in agreement with the steam table data. Furthermore, a continuation of these anomalies to even higher temperatures is insinuated by the steam table data. If this is correct these anomalies would be of significance for partitioning and transport processes in the deep crust and the upper mantle of the earth. (1) Petrenko and Whitnorth (1999): Physics of Ice, Oxford Univ.Press, 1999. (2) Haar, Gallagher and Kell (1984): NBS/NRC Steam Tables, Mc-Graw-Hill. (3) Okhulkov, Demianets and Gorbaty (1994): J.Chem. Phys., 100, 1578--1588 (4) Mirwald (2001): Mitt. Österr. Miner.Ges. 146, 193-195 (5) Mirwald (2002): Ber. Dtsche. Mineralog. Ges., No.1, 2002, p.110 (6) Becher, Cemic and Langer (1983): Geochim. Cosmochim. Acta , 47, 1573-1578. (7) Manning (1994): Geochim. Cosmochim. Acta 58, 4831-4839.

  12. Integer, fractional, and anomalous quantum Hall effects explained with Eyring's rate process theory and free volume concept.

    PubMed

    Hao, Tian

    2017-02-22

    The Hall effects, especially the integer, fractional and anomalous quantum Hall effects, have been addressed using Eyring's rate process theory and free volume concept. The basic assumptions are that the conduction process is a common rate controlled "reaction" process that can be described with Eyring's absolute rate process theory; the mobility of electrons should be dependent on the free volume available for conduction electrons. The obtained Hall conductivity is clearly quantized as with prefactors related to both the magnetic flux quantum number and the magnetic quantum number via the azimuthal quantum number, with and without an externally applied magnetic field. This article focuses on two dimensional (2D) systems, but the approaches developed in this article can be extended to 3D systems.

  13. A severe red tide (Tampa Bay, 2005) causes an anomalous decrease in biological sound.

    PubMed

    Indeck, Katherine L; Simard, Peter; Gowans, Shannon; Lowerre-Barbieri, Susan; Mann, David A

    2015-09-01

    Although harmful algal blooms (HABs) are known to cause morbidity and mortality in marine organisms, their sublethal effects are poorly understood. The purpose of this study was to compare ambient noise levels during a severe HAB event in Tampa Bay, Florida, to those during non-HAB periods. Passive acoustic monitoring was conducted using bottom-mounted autonomous acoustic recorders during a severe HAB in summer 2005, and in summers 2006, 2011 and 2012 (non-severe HAB years). Ambient noise levels were significantly higher during the non-HAB years due to an abundance of snapping shrimp (Alpheidae) sounds and fish chorusing. The difference of sound intensity between the study years is most likely attributable to effects of the HAB on the abundance and/or behaviour of fish and snapping shrimp as a result of mortality and stress-induced behavioural modifications.

  14. Comparison of interaction mechanisms of copper phthalocyanine and nickel phthalocyanine thin films with chemical vapours

    NASA Astrophysics Data System (ADS)

    Ridhi, R.; Singh, Sukhdeep; Saini, G. S. S.; Tripathi, S. K.

    2018-04-01

    The present study deals with comparing interaction mechanisms of copper phthalocyanine and nickel phthalocyanine with versatile chemical vapours: reducing, stable aromatic and oxidizing vapours namely; diethylamine, benzene and bromine. The variation in electrical current of phthalocyanines with exposure of chemical vapours is used as the detection parameter for studying interaction behaviour. Nickel phthalocyanine is found to exhibit anomalous behaviour after exposure of reducing vapour diethylamine due to alteration in its spectroscopic transitions and magnetic states. The observed sensitivities of copper phthalocyanine and nickel phthalcyanine films are different in spite of their similar bond numbers, indicating significant role of central metal atom in interaction mechanism. The variations in electronic transition levels after vapours exposure, studied using UV-Visible spectroscopy confirmed our electrical sensing results. Bromine exposure leads to significant changes in vibrational bands of metal phthalocyanines as compared to other vapours.

  15. Electronic differential for tramcar bogies: system development and performance evaluation by means of numerical simulation

    NASA Astrophysics Data System (ADS)

    Barbera, Andrea N.; Bucca, Giuseppe; Corradi, Roberto; Facchinetti, Alan; Mapelli, Ferdinando

    2014-05-01

    The dynamic behaviour of railway vehicles depends on the wheelset configuration, i.e. solid axle wheelset or independently rotating wheels (IRWs). The self-centring behaviour, peculiar of the solid axle wheelset, makes this kind of wheelset very suitable for tangent track running at low speed: the absence of the self-centring mechanism in the IRWs may lead to anomalous wheel/rail wear, reduced vehicle safety and passengers' discomfort. On the contrary, during negotiation of the sharp curves typical of urban tramways, solid axle wheelsets produce lateral contact forces higher than those of IRWs. This paper illustrates an electronic differential system to be applied to tramcar bogies equipped with wheel-hub motors which allows switching from solid axle in tangent track to IRWs in sharp curve (and vice versa). An electro-mechanical vehicle model is adopted for the design of the control system and for the evaluation of the vehicle dynamic performances.

  16. Searches for anomalous coupling in top-quark interaction with the W boson and b quark, along with searches for quark-flavor-changing neutral currents, in an analysis of data from the CMS experiment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Boos, E. E.; Bunichev, V. E.; Vorotnikov, G. A.

    2016-01-15

    The results of searches for effects beyond the Standard Model in processes of single top-quark production in the CMS experiment are presented. Anomalous contributions of the vector and magnetic types in top-quark interaction with the W boson and b quark and quark-flavor-changing neutral currents in top-quark interaction with the c or u quark via gluon exchange were studied. The respective analysis was performed with the aid of Bayesian neural networks. No statistically significant deviations were found, and upper limits on anomalous couplings at a 95% confidence level were set.

  17. Low-field anomalous magnetic phase in the kagome-lattice shandite C o3S n2S2

    NASA Astrophysics Data System (ADS)

    Kassem, Mohamed A.; Tabata, Yoshikazu; Waki, Takeshi; Nakamura, Hiroyuki

    2017-07-01

    The magnetization process of single crystals of the metallic kagome ferromagnet C o3S n2S2 was carefully measured via magnetization and ac susceptibility. Field-dependent anomalous transitions observed in low fields indicate the presence of an unconventional magnetic phase just below the Curie temperature, TC. The magnetic phase diagrams in low magnetic fields along different crystallographic directions were determined for the first time. The magnetic relaxation measurements at various frequencies covering five orders of magnitude from 0.01 to 1000 Hz indicate markedly slow spin dynamics only in the anomalous phase with characteristic relaxation times longer than 10 s.

  18. Anomalous sound absorption in the Voronoi liquid

    NASA Astrophysics Data System (ADS)

    Farago, Jean; Ruscher, CéLine; Semenov, Alexandr; Baschnagel, Joerg

    The physics of simple fluids in the hydrodynamic limit, and notably the connection between the proper microscopic scales and the macroscopic hydrodynamical description are nowadays well understood. In particular, the three peak shape of the dynamical structure factor S (k , ω) is a universal feature, as well as the k-dependence of the peak position ( k), and width k2 , the latter accounting for the sound attenuation rate. In this talk, I will present a theoretical model of monodisperse fluid, whose interactions are defined via the Voronoi tessellations of the configurations (called the Voronoi liquid and first studied in), which displays at low temperatures a marked violation of the universal features of S (k , ω) with sound attenuation rate only k . This anomalous behaviour, which apparently violates the basic symmetries of the liquid state, is traced back to the existence of a timescale which is both (1) short enough for the viscoelastic features of the liquid to impact the relaxational dynamics and (2) long enough for the momentum diffusion to be substantially slower than the sound propagation on that characteristic time.

  19. The Magnetar Nature and the Outburst Mechanism of a Transient Anomalous X-ray Pulsar

    NASA Technical Reports Server (NTRS)

    Guver, Tolga; Ozel, Feryal; Gogus, Ersin; Kouveliotou, Chryssa

    2007-01-01

    Anomalous X-ray Pulsars (AXPs) belong to a class of neutron stars believed to harbor the strongest magnetic fields in the universe, as indicated by their energetic bursts and their rapid spindowns. However, a direct measurement of their surface field strengths has not been made to date. It is also not known whether AXP outbursts result from changes in the neutron star magnetic field or crust properties. Here we report the first, spectroscopic measurement of the surface magnetic field strength of an AXP, XTE J1810-197, and solidify its magnetar nature. The field strength obtained from detailed spectral analysis and modeling is remarkably close to the value inferred from the rate of spindown of this source and remains nearly constant during numerous observations spanning over two orders of magnitude in source flux. The surface temperature, on the other hand, declines steadily and dramatically following the 2003 outburst of this source. Our findings demonstrate that heating occurs in the upper neutron star crust during an outburst and sheds light on the transient behaviour of AXPs.

  20. Detailed Physical Modeling Reveals the Magnetar Nature of a Transient Anomalous X-ray Pulsar

    NASA Technical Reports Server (NTRS)

    Guever, T.; Oezel, F.; Goegues, E.; Kouveliotou, C.

    2007-01-01

    Anomalous X-ray Pulsars (AXPs) belong to a class of neutron stars believed to harbor the strongest magnetic fields in the universe, as indicated by their energetic bursts and their rapid spindowns. However, a direct measurement of their surface field strengths has not been made to date. It is also not known whether AXP outbursts result from changes in the neutron star magnetic field or crust properties. Here we report the first, spectroscopic measurement of the surface magnetic field strength of an AXP, XTE J1810-197, and solidify its magnetar nature. The field strength obtained from detailed spectral analysis and modeling is remarkably close to the value inferred from the rate of spindown of this source and remains nearly constant during numerous observations spanning over two orders of magnitude in source flux. The surface temperature, on the other hand, declines steadily and dramatically following the 2003 outburst of this source. Our findings demonstrate that heating occurs in the upper neutron star crust during an outburst and sheds light on the transient behaviour of AXPs.

  1. Measurement of $$\\sigma\\cdot$$Br($$W + \\gamma$$) and $$\\sigma\\cdot$$BR($$Z + \\gamma$$) and Search for Anomalous $W$ ($$\\gamma$$) and $Z$ ($$\\gamma$$) Couplings at $$\\sqrt{s}$$ = 1.8-TeV

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Vondracek, Mark Frank

    1994-11-01

    Measurements of the production cross section times branching ratio for W + γ and Z + γ processes, where the W decays into a muon and neutrino and the Z decays into a muon pair, have been made from the analysis of 18.6±0.7 pb -1 of high-P T muon data from proton-antiproton (pmore » $$\\bar{p}$$) collisions. The data were collected with the Collider Detector at Fermilab (CDF) during the 1992-93 run. In a search for central photons (|η| < 1.1) with transverse energy above 7 GeV and angular separation from the muon by at least ΔR = 0. 7, where ΔR = √(Δ Φ 2+ Δη 2) , we find 7 W γ and 4 Zγ candidates. This translates into cross section times branching ratios of 9.0 ± 6.4 pb for the Wγ process and 6.6 ± 3.4 pb for the Zγ process. Separate measurements were made for photon E T values above 11 Ge V and 15 Ge V. The cross section times branching ratio results were used to calculate a series of cross section ratios. An analysis designed to search for anomalous couplings between the gauge bosons was also carried out using these results. Assuming only one anomalous coupling to be non-zero at a time, the 95% CL limits on W γ anomalous couplings are, -3.7 < Δ κ< 3.7, -1.2 < λ< 1.2, -3.8 < $$\\tilde{κ}$$, < 3.8 and -1.2 < $$\\tilde{λ}$$ < 1.2. For ZZγ anomalous couplings the experimental limits are measured to be, at the 95% CL, -4.6 < h$$Z\\atop{30}$$ (h$$Z\\atop{10}$$ ) < 4.6 and -1.1 < h$$Z\\atop{40}$$ (h$$Z\\atop{20}$$) < 1.1. For Zγγ anomalous couplings the experimental limits are measured to be, at the 95% CL, -4.9 < h$$γ\\atop{30}$$ ($$γ\\atop{10}$$) < 4.9 and -1.2 < $$γ\\atop{40}$$ ( $$γ\\atop{20}$$ ) < 1.2. Limits are placed on electromagnetic multi pole moments for both the W and Z bosons using the measured limits of the anomalous couplings, and are presented in this thesis. All of the measurements presented in this thesis are consistent with Standard Model expectations.« less

  2. Normal and anomalous transport phenomena in two-dimensional NaCl, MoS2 and honeycomb surfaces

    NASA Astrophysics Data System (ADS)

    Mbemmo, A. M. Fopossi; Kenmoé, G. Djuidjé; Kofané, T. C.

    2018-04-01

    Understanding the effects of anisotropy and substrate shape on the stochastic processes is critically needed for the improvement of the quality of the transport information. The effect of biharmonic force on the transport phenomena of a particle in two-dimensional is investigated in the framework of three representative substrate lattices: NaCl, MoS2 and honeycomb. We focus on the particles drift velocity, to characterize the transport properties in the system. Normal and anomalous transport are identified for a particular set of the system parameters such as the biharmonic parameter, the bias force, the phase-lag of two signals, as well as the noise amplitude. According to the direction ψ where the bias force is applied, we determine the biharmonic parameter ɛ for the presence of anomalous transport and show that for the NaCl surface, the anomalous transport is observed for 2 < ɛ < 10. For the MoS2 surface, it appears at monochromatic driven (ɛ = 0) and for 3 < ɛ < 9. In particular for the honeycomb surface anomalous transport is generated for 0 ⩽ ɛ < 6 only when ψ > 30 °.

  3. Numerical schemes for anomalous diffusion of single-phase fluids in porous media

    NASA Astrophysics Data System (ADS)

    Awotunde, Abeeb A.; Ghanam, Ryad A.; Al-Homidan, Suliman S.; Tatar, Nasser-eddine

    2016-10-01

    Simulation of fluid flow in porous media is an indispensable part of oil and gas reservoir management. Accurate prediction of reservoir performance and profitability of investment rely on our ability to model the flow behavior of reservoir fluids. Over the years, numerical reservoir simulation models have been based mainly on solutions to the normal diffusion of fluids in the porous reservoir. Recently, however, it has been documented that fluid flow in porous media does not always follow strictly the normal diffusion process. Small deviations from normal diffusion, called anomalous diffusion, have been reported in some experimental studies. Such deviations can be caused by different factors such as the viscous state of the fluid, the fractal nature of the porous media and the pressure pulse in the system. In this work, we present explicit and implicit numerical solutions to the anomalous diffusion of single-phase fluids in heterogeneous reservoirs. An analytical solution is used to validate the numerical solution to the simple homogeneous case. The conventional wellbore flow model is modified to account for anomalous behavior. Example applications are used to show the behavior of wellbore and wellblock pressures during the single-phase anomalous flow of fluids in the reservoirs considered.

  4. Tracking single Kv2.1 channels in live cells reveals anomalous subdiffusion and ergodicity breaking

    NASA Astrophysics Data System (ADS)

    Weigel, Aubrey; Simon, Blair; Tamkun, Michael; Krapf, Diego

    2011-03-01

    The dynamic organization of the plasma membrane is responsible for essential cellular processes, such as receptor trafficking and signaling. By studying the dynamics of transmembrane proteins a greater understanding of these processes as a whole can be achieved. It is broadly observed that the diffusion pattern of membrane protein displays anomalous subdiffusion. However, the mechanisms responsible for this behavior are not yet established. We explore the dynamics of the voltage gated potassium channel Kv2.1 by using single-particle tracking. We analyze Kv2.1 channel trajectories in terms of the time and ensemble distributions of square displacements. Our results reveal that all Kv2.1 channels experience anomalous subdiffusion and we observe that the Kv2.1 diffusion pattern is non-ergodic. We further investigated the role of the actin cytoskeleton in these channel dynamics by applying actin depolymerizing drugs. It is seen that with the breakdown of the actin cytoskeleton the Kv2.1 channel trajectories recover ergodicity.

  5. Anomalous Micellization of Pluronic Block Copolymers

    NASA Astrophysics Data System (ADS)

    Leonardi, Amanda; Ryu, Chang Y.

    2014-03-01

    Poly(ethylene oxide) - poly(propylene oxide) - poly(ethylene oxide) (PEO-PPO-PEO) block copolymers, commercially known as Pluronics, are a unique family of amphiphilic triblock polymers, which self-assemble into micelles in aqueous solution. These copolymers have shown promise in therapeutic, biomedical, cosmetic, and nanotech applications. As-received samples of Pluronics contain low molecular weight impurities (introduced during the manufacturing and processing), that are ignored in most applications. It has been observed, however, that in semi-dilute aqueous solutions, at concentrations above 1 wt%, the temperature dependent micellization behavior of the Pluronics is altered. Anomalous behavior includes a shift of the critical micellization temperature and formation of large aggregates at intermediate temperatures before stable sized micelles form. We attribute this behavior to the low molecular weight impurities that are inherent to the Pluronics which interfere with the micellization process. Through the use of Dynamic Light Scattering and HPLC, we compared the anomalous behavior of different Pluronics of different impurity levels to their purified counterparts.

  6. Effects of environmental enrichment on behaviour, physiology and performance of pigs: A review.

    PubMed

    Mkwanazi, Mbusiseni Vusumuzi; Ncobela, Cyprial Ndumiso; Kanengoni, Arnold Tapera; Chimonyo, Michael

    2017-06-26

    The aim of this paper is to critically analyse and synthesise existing knowledge concerning the use of environmental enrichment and its effect on behaviour, physiology and performance of pigs housed in intensive production systems. The objective is also to provide clarity as to what constitute successful enrichment and recommend on when and how enrichment should be used. Environmental enrichment is usually understood as an attempt to improve animal welfare and to lesser extent, performance. Common enrichment objects used are straw bedding, suspended rope and wood shavings, toys, rubber tubing, coloured plastic keys, table tennis balls, chains and strings. These substrates need to be chewable, deformable, destructible and ingestible. For enrichment to be successful four goals are the prerequisite. Firstly, enrichment should increase the number and range of normal behaviours (2) prevent the phenomenon of anomalous behaviours or reduce their frequency (3) increase positive use of the environment such as space and (4) increase the ability of the animals to deal with behavioural and physiological challenges. The performance, behaviour and physiology of pigs in enriched environments is similar or in some cases slightly better when compared with barren environments. In studies where there was no improvement, it should be born in mind that enriching the environment may not always be practical and yield positive results due to factors such as type of enrichment substrates, duration of provision and type of enrichment used. The review also identifies possible areas which still need further research, especially in understanding the role of enrichment, novelty, breed differences and other enrichment alternatives.

  7. Spin-State Transition in La1-xSrxCoO3 Single Crystals

    NASA Astrophysics Data System (ADS)

    Bhardwaj, S.; Prabhakaran, D.; Awasthi, A. M.

    2011-07-01

    We present a study of the thermal conductivity (κ), specific heat (Cp) and Raman spectra of La1-xSrxCoO3 (x = 0,0.1) single crystals. Both the specimens have low thermal conductivity and board Raman peaks, arising from strong scattering of phonons by lattice disorder, produced by (and doping-enhanced) spin-states admixture of the Co3+ ions. The thermal conductivity anomalously deviates from ˜1/T behaviour at high (room) temperatures, expected of an insulator. High-temperature specific heat reveals large decrease in the metal-insulator (M-I) transition temperature with Sr-doping.

  8. Random walks on combs

    NASA Astrophysics Data System (ADS)

    Durhuus, Bergfinnur; Jonsson, Thordur; Wheater, John F.

    2006-02-01

    We develop techniques to obtain rigorous bounds on the behaviour of random walks on combs. Using these bounds, we calculate exactly the spectral dimension of random combs with infinite teeth at random positions or teeth with random but finite length. We also calculate exactly the spectral dimension of some fixed non-translationally invariant combs. We relate the spectral dimension to the critical exponent of the mass of the two-point function for random walks on random combs, and compute mean displacements as a function of walk duration. We prove that the mean first passage time is generally infinite for combs with anomalous spectral dimension.

  9. Turbulence, flow and transport: hints from reversed field pinch

    NASA Astrophysics Data System (ADS)

    Vianello, N.; Antoni, V.; Spada, E.; Spolaore, M.; Serianni, G.; Cavazzana, R.; Bergsåker, H.; Cecconello, M.; Drake, J. R.

    2006-04-01

    The interplay between sheared E × B flows and turbulence has been experimentally investigated in the edge region of the Extrap-T2R reversed field pinch experiment. Electrostatic fluctuations are found to rule the momentum balance equation representing the main driving term for sheared flows which counterbalances anomalous viscous damping. The driving role of electrostatic fluctuations is proved by the spatial structure of the Reynolds stress and by the time behaviour of the mean energy production term which supports the existence of an energy exchange from the small scales of turbulence to the larger scales of the mean flow.

  10. Hadean silicate differentiation preserved by anomalous 142Nd/144Nd ratios in the Réunion hotspot source

    NASA Astrophysics Data System (ADS)

    Peters, Bradley J.; Carlson, Richard W.; Day, James M. D.; Horan, Mary F.

    2018-03-01

    Active volcanic hotspots can tap into domains in Earth’s deep interior that were formed more than two billion years ago. High-precision data on variability in tungsten isotopes have shown that some of these domains resulted from differentiation events that occurred within the first fifty million years of Earth history. However, it has not proved easy to resolve analogous variability in neodymium isotope compositions that would track regions of Earth’s interior whose composition was established by events occurring within roughly the first five hundred million years of Earth history. Here we report 142Nd/144Nd ratios for Réunion Island igneous rocks, some of which are resolvably either higher or lower than the ratios in modern upper-mantle domains. We also find that Réunion 142Nd/144Nd ratios correlate with helium-isotope ratios (3He/4He), suggesting parallel behaviour of these isotopic systems during very early silicate differentiation, perhaps as early as 4.39 billion years ago. The range of 142Nd/144Nd ratios in Réunion basalts is inconsistent with a single-stage differentiation process, and instead requires mixing of a conjugate melt and residue formed in at least one melting event during the Hadean eon, 4.56 billion to 4 billion years ago. Efficient post-Hadean mixing nearly erased the ancient, anomalous 142Nd/144Nd signatures, and produced the relatively homogeneous 143Nd/144Nd composition that is characteristic of Réunion basalts. Our results show that Réunion magmas tap into a particularly ancient, primitive source compared with other volcanic hotspots, offering insight into the formation and preservation of ancient heterogeneities in Earth’s interior.

  11. A new approach to plasmasphere refilling: Anomalous plasma effects

    NASA Technical Reports Server (NTRS)

    Singh, N.

    1991-01-01

    During the last 10 months of the grant, both laminar and anomalous plasma processes occurring during the refilling of the outer plasmasphere after magnetic storms are investigated. Theoretical investigations were based on two types of models: (1) two-stream hydrodynamic model in which plasma flows from the conjugate ionospheres are treated as separate fluids and the ion temperature anisotropies are treated self-consistently; and (2) large-scale particle-in-cell code.

  12. A new fractional operator of variable order: Application in the description of anomalous diffusion

    NASA Astrophysics Data System (ADS)

    Yang, Xiao-Jun; Machado, J. A. Tenreiro

    2017-09-01

    In this paper, a new fractional operator of variable order with the use of the monotonic increasing function is proposed in sense of Caputo type. The properties in term of the Laplace and Fourier transforms are analyzed and the results for the anomalous diffusion equations of variable order are discussed. The new formulation is efficient in modeling a class of concentrations in the complex transport process.

  13. Anomalous basal ganglia connectivity and obsessive–compulsive behaviour in patients with Prader Willi syndrome

    PubMed Central

    Pujol, Jesus; Blanco-Hinojo, Laura; Esteba-Castillo, Susanna; Caixàs, Assumpta; Harrison, Ben J.; Bueno, Marta; Deus, Joan; Rigla, Mercedes; Macià, Dídac; Llorente-Onaindia, Jone; Novell-Alsina, Ramón

    2016-01-01

    Background Prader Willi syndrome is a genetic disorder with a behavioural expression characterized by the presence of obsessive–compulsive phenomena ranging from elaborate obsessive eating behaviour to repetitive skin picking. Obsessive–compulsive disorder (OCD) has been recently associated with abnormal functional coupling between the frontal cortex and basal ganglia. We have tested the potential association of functional connectivity anomalies in basal ganglia circuits with obsessive–compulsive behaviour in patients with Prader Willi syndrome. Methods We analyzed resting-state functional MRI in adult patients and healthy controls. Whole-brain functional connectivity maps were generated for the dorsal and ventral aspects of the caudate nucleus and putamen. A selected obsessive–compulsive behaviour assessment included typical OCD compulsions, self picking and obsessive eating behaviour. Results We included 24 adults with Prader Willi syndrome and 29 controls in our study. Patients with Prader Willi syndrome showed abnormal functional connectivity between the prefrontal cortex and basal ganglia and within subcortical structures that correlated with the presence and severity of obsessive–compulsive behaviours. In addition, abnormally heightened functional connectivity was identified in the primary sensorimotor cortex–putamen loop, which was strongly associated with self picking. Finally, obsessive eating behaviour correlated with abnormal functional connectivity both within the basal ganglia loops and between the striatum and the hypothalamus and the amygdala. Limitations Limitations of the study include the difficulty in evaluating the nature of content of obsessions in patients with Prader Willi Syndrome and the risk of excessive head motion artifact on brain imaging. Conclusion Patients with Prader Willi syndrome showed broad functional connectivity anomalies combining prefrontal loop alterations characteristic of OCD with 1) enhanced coupling in the primary sensorimotor loop that correlated with the most impulsive aspects of the behaviour and 2) reduced coupling of the ventral striatum with limbic structures for basic internal homeostasis that correlated with the obsession to eat. PMID:26645739

  14. Rad4 recognition-at-a-distance: Physical basis of conformation-specific anomalous diffusion of DNA repair proteins.

    PubMed

    Kong, Muwen; Van Houten, Bennett

    2017-08-01

    Since Robert Brown's first observations of random walks by pollen particles suspended in solution, the concept of diffusion has been subject to countless theoretical and experimental studies in diverse fields from finance and social sciences, to physics and biology. Diffusive transport of macromolecules in cells is intimately linked to essential cellular functions including nutrient uptake, signal transduction, gene expression, as well as DNA replication and repair. Advancement in experimental techniques has allowed precise measurements of these diffusion processes. Mathematical and physical descriptions and computer simulations have been applied to model complicated biological systems in which anomalous diffusion, in addition to simple Brownian motion, was observed. The purpose of this review is to provide an overview of the major physical models of anomalous diffusion and corresponding experimental evidence on the target search problem faced by DNA-binding proteins, with an emphasis on DNA repair proteins and the role of anomalous diffusion in DNA target recognition. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Coherent Infra-Red as logically necessary to explain Piagetian psychology and neuro-microanatomy — Two independent corroborations for Gurwitsch's findings, and the importance of self-consistent theory

    NASA Astrophysics Data System (ADS)

    Traill, Robert R.

    2011-12-01

    We can infer mechanisms underlying advanced human intelligence via •physics, chemistry and information-technology; but also •epistemology: analysing all knowledge-building processes (based on selection amongst micro-ideas). Hence Piaget offered "schèmes" as such items of thought/action, to account for actual human behaviour. In microphysiological terms, basic "schèmes" should have digital properties and a one-dimensional organization. That implied RNA-like molecules (and their "chorus" groups). — However for the necessary fast intermolecular communication, traditional action-potential "spikes" would be much too coarse. The alternative is Infra-Red. It then appears that myelinated nerve fibres seem suitable for an unexpected second role as coaxial cables for IR! Such opticalinterpretations also explain several enigmas: •What keeps (myelin-thickness / axon-diameter) ≈ constant? — (a mystery since 1905). •Why PNS myelination is delayed until the axon diameter reaches 1μm. •Why myelin often stops growing at a predictable angle in its wrapping. •Callahan's anomalous failure to detect sensory action-potentials even though his insects were responding to invisible IR signals. (Meanwhile RNA-like coding explains inherited behavioural traits, and memory-"recording" as Darwinian!) The important point: Here IR is independently identified as a necessary solution to logistical problems. In contrast the Gurwitsch tradition first discovered emissions, and then sought explanations. Thus the two approaches corroborate.

  16. Anomaly Detection in Dynamic Networks

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Turcotte, Melissa

    2014-10-14

    Anomaly detection in dynamic communication networks has many important security applications. These networks can be extremely large and so detecting any changes in their structure can be computationally challenging; hence, computationally fast, parallelisable methods for monitoring the network are paramount. For this reason the methods presented here use independent node and edge based models to detect locally anomalous substructures within communication networks. As a first stage, the aim is to detect changes in the data streams arising from node or edge communications. Throughout the thesis simple, conjugate Bayesian models for counting processes are used to model these data streams. Amore » second stage of analysis can then be performed on a much reduced subset of the network comprising nodes and edges which have been identified as potentially anomalous in the first stage. The first method assumes communications in a network arise from an inhomogeneous Poisson process with piecewise constant intensity. Anomaly detection is then treated as a changepoint problem on the intensities. The changepoint model is extended to incorporate seasonal behavior inherent in communication networks. This seasonal behavior is also viewed as a changepoint problem acting on a piecewise constant Poisson process. In a static time frame, inference is made on this extended model via a Gibbs sampling strategy. In a sequential time frame, where the data arrive as a stream, a novel, fast Sequential Monte Carlo (SMC) algorithm is introduced to sample from the sequence of posterior distributions of the change points over time. A second method is considered for monitoring communications in a large scale computer network. The usage patterns in these types of networks are very bursty in nature and don’t fit a Poisson process model. For tractable inference, discrete time models are considered, where the data are aggregated into discrete time periods and probability models are fitted to the communication counts. In a sequential analysis, anomalous behavior is then identified from outlying behavior with respect to the fitted predictive probability models. Seasonality is again incorporated into the model and is treated as a changepoint model on the transition probabilities of a discrete time Markov process. Second stage analytics are then developed which combine anomalous edges to identify anomalous substructures in the network.« less

  17. The Leicester AATSR Global Analyser (LAGA) - Giving Young Students the Opportunity to Examine Space Observations of Global Climate-Related Processes

    NASA Astrophysics Data System (ADS)

    Llewellyn-Jones, David; Good, Simon; Corlett, Gary

    A pc-based analysis package has been developed, for the dual purposes of, firstly, providing ‘quick-look' capability to research workers inspecting long time-series of global satellite datasets of Sea-surface Temperature (SST); and, secondly, providing an introduction for students, either undergraduates, or advanced high-school students to the characteristics of commonly used analysis techniques for large geophysical data-sets from satellites. Students can also gain insight into the behaviour of some basic climate-related large-scale or global processes. The package gives students immediate access to up to 16 years of continuous global SST data, mainly from the Advanced Along-Track Scanning Radiometer, currently flying on ESA's Envisat satellite. The data are available and are presented in the form of monthly averages and spatial averaged to half-degree or one-sixth degree longitude-latitude grids. There are simple button-operated facilities for defining and calculating box-averages; producing time-series of such averages; defining and displaying transects and their evolution over time; and the examination anomalous behaviour by displaying the difference between observed values and values derived from climatological means. By using these facilities a student rapidly gains familiarity with such processes as annual variability, the El Nĩo effect, as well as major current systems n such as the Gulf Stream and other climatically important phenomena. In fact, the student is given immediate insights into the basic methods of examining geophysical data in a research context, without needing to acquire special analysis skills are go trough lengthy data retrieval and preparation procedures which are more generally required, as precursors to serious investigation, in the research laboratory. This software package, called the Leicester AAATSR Global Analyser (LAGA), is written in a well-known and widely used analysis language and the package can be run by using software that is readily available free-of-charge.

  18. Using Fluvial Geomorphology as a Physical Template in Process-Based and Recovery Enhancement Approaches to River Management

    NASA Astrophysics Data System (ADS)

    Fryirs, K.

    2016-12-01

    In an `era of river repair' fluvial geomorphology has emerged as a key science in river management practice. Geomorphologists are ideally placed to use their science in an applied manner to provide guidance on the impact of floods and droughts, landuse and climate change, and water use on river forms, processes and evolution. Increasingly, fluvial geomorphologists are also asked to make forecasts about how systems might adjust in the future, and to work with managers to implement strategies on-the-ground. Using case study material from Eastern Australia (Bega, Hunter, Wollombi and Lockyer catchments) I will focus on how process-based understanding of rivers has developed and evolved to provide a coherent physical template for effective and proactive, river management practice. I will focus on four key principles and demonstrate how geomorphology has been, and should continue to be, used in process-based, recovery enhancement approaches to river management. How understanding the difference between river behaviour and river change is used to determine how a river is `expected' to function, and how to identify anomalous processes requiring a treatment response. How understanding evolutionary trajectory is used to make future forecasts on river condition and recovery potential, and how working with processes can enhance river recovery. How geomorphic information can be used as a physical template atop which to analyse a range of biotic processes and habitat outcomes. How geomorphic information is used to effectively prioritise and plan river conservation and rehabilitation activities as part of catchment and region-scale action plans.

  19. The behaviour of platelets in natural diamonds and the development of a new mantle thermometer

    NASA Astrophysics Data System (ADS)

    Speich, L.; Kohn, S. C.; Bulanova, G. P.; Smith, C. B.

    2018-05-01

    Platelets are one of the most common defects occurring in natural diamonds but their behaviour has not previously been well understood. Recent technical advances, and a much improved understanding of the correct interpretation of the main infrared (IR) feature associated with platelets (Speich et al. 2017), facilitated a systematic study of platelets in 40 natural diamonds. Three different types of platelet behaviour were identified here. Regular diamonds show linear correlations between both B-centre concentrations and platelet density and also between platelet size and platelet density. Irregular diamonds display reduced platelet density due to platelet breakdown, anomalously large or small platelets and a larger platelet size distribution. These features are indicative of high mantle storage temperatures. Finally, a previously unreported category of subregular diamonds is defined. These diamonds experienced low mantle residence temperatures and show smaller than expected platelets. Combining the systematic variation in platelet density with temperatures of mantle storage, determined by nitrogen aggregation, we can demonstrate that platelet degradation proceeds at a predictable rate. Thus, in platelet-bearing diamonds where N aggregation is complete, an estimate of annealing temperature can now be made for the first time.

  20. Magnetism from Fe2O3 nanoparticles embedded in amorphous SiO2 matrix

    NASA Astrophysics Data System (ADS)

    Sendil Kumar, A.; Bhatnagar, Anil K.

    2018-02-01

    Fe2O3 nanoparticles are embedded in amorphous SiO2 matrix by coprecipitation method with varying concentrations. Conditions are optimized to get almost monodispersed Fe2O3 nanoparticles with high chemical stability. Microstructure of synthesized nanoparticles is well characterized and found that Fe2O3 is in nanocrystalline form and embedded uniformly in amorphous SiO2 matrix. Enhanced surface reactivity is found for nanoparticles which influences physical properties of the SiO2 supported Fe2O3 system due to adsorption. In oxide nanoparticles, significant number of defect sites at the surface is expected but when supported medium such as SiO2 it reduces this defect concentration. Field- and temperature-dependent magnetisation studies on these samples show superparamagnetic behaviour. Superparamagnetic behaviour is seen in all the concentration systems but the coercivity observed in the lower concentration systems is found to be anomalous compared to that of higher concentrations. The observed magnetic behaviour comes from either unsaturated bond existing due to the absence of anions at the surface of nanoparticles or reconstruction of atomic orbitals taking place at interface of Fe2O3-SiO2 system.

  1. Fibre systems for future astronomy: anomalous wavelength-temperature effects

    NASA Astrophysics Data System (ADS)

    Poppett, C. L.; Allington-Smith, J. R.

    2007-07-01

    Focal ratio degradation is an important property of optical fibres that determines the design and cost of instruments using fibres. Motivated by the importance of fibres in feeding instruments on Extremely Large Telescopes, the need for cryogenic-cooling to reduce thermal background and the desire for broad-band performance, we have studied the dependency of focal ratio degradation (FRD) on both temperature and wavelength. This shows a small but significant reduction in performance when cooled as expected from previous work. We also find an increase in FRD with wavelength broadly consistent with theory at room temperature but this dependency reverses in sign when the fibres are cooled to 77K, contrary to existing theory. We parameterize the wavelength dependency by an ad hoc extension to an existing model but it is clear that existing theory does not provide a good description of the operation of fibres in astronomical systems. This unexpected behaviour, which may relate to frozen-in stress from the manufacturing process, will need to be taken into account when designing future fibre systems.

  2. Evidence for anomalous prompt photons in deep inelastic muon scattering at 200 GeV

    NASA Astrophysics Data System (ADS)

    Aubert, J. J.; Bassompierre, G.; Becks, K. H.; Benchouk, C.; Best, C.; Böhm, E.; De Bouard, X.; Brasse, F. W.; Broll, C.; Brown, S. C.; Carr, J.; Clifft, R.; Cobb, J. H.; Coignet, G.; Combley, F.; Court, G. R.; D'Agostini, G.; Dau, W. D.; Davies, J. K.; Déclais, Y.; Dosselli, U.; Drees, J.; Edwards, A.; Edwards, M.; Favier, J.; Ferrero, M. I.; Flauger, W.; Forsbach, H.; Gabathuler, E.; Gamet, R.; Gayler, J.; Gerhardt, V.; Gössling, C.; Gregory, P.; Haas, J.; Hamacher, K.; Hayman, P.; Henckes, M.; Ingelman, G.; Korbel, V.; Landgraf, U.; Leenen, M.; Maire, M.; Mohr, W.; Montgomery, H. E.; Moser, K.; Muont, R. P.; Nagy, E.; Nassalski, J.; Norton, P. R.; McNicholas, J.; Osborne, A. M.; Payre, P.; Peroni, C.; Pessard, H.; Pietrzyk, U.; Rith, K.; Schneegans, M.; Sloan, T.; Stier, H. E.; Stockhausen, W.; Thénard, J. M.; Thompson, J. C.; Urban, L.; Wahlen, H.; Whalley, M.; Williams, D.; Williams, W. S. C.; Williamson, J.; Wimpenny, S. J.; European Muon Collaboration

    1989-02-01

    The inclusive yield of photons has been measured from deep inelastic interactions of 200 GeV muons on hydrogen. After subtracting the contributions from hadron electromagnetic decays and Bethe-Heitler muon bremsstrahlung, residual photons are observed at low pT and low z at a mean level of 0.15±0.06 per interaction. The quark Compton scattering process is unable to explain the data, thus indicating an anomalous photon production.

  3. On the quantum mechanics of consciousness, with application to anomalous phenomena

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jahn, R.G.; Dunne, B.J.

    1986-08-01

    Theoretical explication of a growing body of empirical data on consciousness-related anomalous phenomena is unlikely to be achieved in terms of known physical processes. Rather, it will first be necessary to formulate the basic role of consciousness in the definition of reality before such anomalous experience can adequately be represented. This paper takes the position that reality is constituted only in the interaction of consciousness with its environment, and therefore that any scheme of conceptual organization developed to represent that reality must reflect the processes of consciousness as well as those of its environment. In this spirit, the concepts andmore » formalisms of elementary quantum mechanics, as originally proposed to explain anomalous atomic-scale physical phenomena, are appropriated via metaphor to represent the general characteristics of consciousness interacting with any environment. More specifically, if consciousness is represented by a quantum mechanical wave function, and its environment by an appropriate potential profile, Schrodinger wave mechanics defines eigenfunctions and eigenvalues that can be associated with the cognitive and emotional experiences of that consciousness in that environment. To articulate this metaphor it is necessary to associate certain aspects of the formalism, such as the coordinate system, the quantum numbers, and even the metric itself, with various impressionistic descriptors of consciousness, such as its intensity, perspective, approach/avoidance attitude, balance between cognitive and emotional activity, and receptive/assertive disposition.« less

  4. Anomalous diffusion due to hindering by mobile obstacles undergoing Brownian motion or Orstein-Ulhenbeck processes.

    PubMed

    Berry, Hugues; Chaté, Hugues

    2014-02-01

    In vivo measurements of the passive movements of biomolecules or vesicles in cells consistently report "anomalous diffusion," where mean-squared displacements scale as a power law of time with exponent α<1 (subdiffusion). While the detailed mechanisms causing such behaviors are not always elucidated, movement hindrance by obstacles is often invoked. However, our understanding of how hindered diffusion leads to subdiffusion is based on diffusion amidst randomly located immobile obstacles. Here, we have used Monte Carlo simulations to investigate transient subdiffusion due to mobile obstacles with various modes of mobility. Our simulations confirm that the anomalous regimes rapidly disappear when the obstacles move by Brownian motion. By contrast, mobile obstacles with more confined displacements, e.g., Orstein-Ulhenbeck motion, are shown to preserve subdiffusive regimes. The mean-squared displacement of tracked protein displays convincing power laws with anomalous exponent α that varies with the density of Orstein-Ulhenbeck (OU) obstacles or the relaxation time scale of the OU process. In particular, some of the values we observed are significantly below the universal value predicted for immobile obstacles in two dimensions. Therefore, our results show that subdiffusion due to mobile obstacles with OU type of motion may account for the large variation range exhibited by experimental measurements in living cells and may explain that some experimental estimates are below the universal value predicted for immobile obstacles.

  5. General pulsed-field gradient signal attenuation expression based on a fractional integral modified-Bloch equation

    NASA Astrophysics Data System (ADS)

    Lin, Guoxing

    2018-10-01

    Anomalous diffusion has been investigated in many polymer and biological systems. The analysis of PFG anomalous diffusion relies on the ability to obtain the signal attenuation expression. However, the general analytical PFG signal attenuation expression based on the fractional derivative has not been previously reported. Additionally, the reported modified-Bloch equations for PFG anomalous diffusion in the literature yielded different results due to their different forms. Here, a new integral type modified-Bloch equation based on the fractional derivative for PFG anomalous diffusion is proposed, which is significantly different from the conventional differential type modified-Bloch equation. The merit of the integral type modified-Bloch equation is that the original properties of the contributions from linear or nonlinear processes remain unchanged at the instant of the combination. From the modified-Bloch equation, the general solutions are derived, which includes the finite gradient pulse width (FGPW) effect. The numerical evaluation of these PFG signal attenuation expressions can be obtained either by the Adomian decomposition, or a direct integration method that is fast and practicable. The theoretical results agree with the continuous-time random walk (CTRW) simulations performed in this paper. Additionally, the relaxation effect in PFG anomalous diffusion is found to be different from that in PFG normal diffusion. The new modified-Bloch equations and their solutions provide a fundamental tool to analyze PFG anomalous diffusion in nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI).

  6. Students' Progression in Monitoring Anomalous Results Obtained in Inquiry-Based Laboratory Tasks

    NASA Astrophysics Data System (ADS)

    Crujeiras-Pérez, Beatriz; Jiménez-Aleixandre, Maria Pilar

    2017-07-01

    This paper examines students' engagement in monitoring anomalous results across a 2-year longitudinal study with 9th and 10th graders (14-15 and 15-16 years of age). The context is a set of five inquiry-based laboratory tasks, requiring students to plan and carry out investigations. The study seeks to examine students' interpretation of data, in particular anomalous results generated by them during the process of solving the tasks, and their ability to monitor them. Data collected include video and audio recordings as well as students' written products. For the analysis, two rubrics were developed drawing on Chinn and Brewer (Cognition and Instruction, 19, 323-393, 2001) and Hmelo-Silver et al. (Science Education, 86, 219-243, 2002). The findings point to a pattern of progress in students' responses across the 2 years: (a) responses revealing a low capacity of monitoring due to not recognizing the data as anomalous or recognizing it as anomalous but being unable to explain their causes are more frequent in the first tasks and (b) responses revealing an improved capacity of monitoring are more frequent in the last tasks. The factors influencing students' regulation of their performances, as the requirement of planning, and specific scaffolding based on activity theory are discussed.

  7. Anomalous behavior of B{sub 1g} mode in highly transparent anatase nano-crystalline Nb-doped Titanium Dioxide (NTO) thin films

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gautam, Subodh K., E-mail: subodhkgtm@gmail.com, E-mail: fouran@gmail.com; Ojha, S.; Singh, Fouran, E-mail: subodhkgtm@gmail.com, E-mail: fouran@gmail.com

    2015-12-15

    The effect of Niobium doping and size of crystallites on highly transparent nano-crystalline Niobium doped Titanium Dioxide (NTO) thin films with stable anatase phase are reported. The Nb doping concentration is varied within the solubility limit in TiO{sub 2} lattice. Films were annealed in controlled environment for improving the crystallinity and size of crystallites. Elemental and thickness analysis were carried out using Rutherford backscattering spectrometry and cross sectional field emission scanning electron microscopy. Structural characteristics reveal a substitutional incorporation of Nb{sup +5} in the TiO{sub 2} lattice which inhibits the anatase crystallites growth with increasing the doping percentage. The micro-Ramanmore » (MR) spectra of films with small size crystallites shows stiffening of about 4 cm{sup −1} for the E{sub g(1)} mode and is ascribed to phonon confinement and non-stoichiometry. In contrast, B{sub 1g} mode exhibits a large anomalous softening of 20 cm{sup −1} with asymmetrical broadening; which was not reported for the case of pure TiO{sub 2} crystallites. This anomalous behaviour is explained by contraction of the apical Ti-O bonds at the surface upon substitutional Nb{sup 5+} doping induced reduction of Ti{sup 4+} ions also known as hetero-coordination effect. The proposed hypotheses is manifested through studying the electronic structure and phonon dynamics by performing the near edge x-ray absorption fine structure (NEXAFS) and temperature dependent MR down to liquid nitrogen temperature on pure and 2.5 at.% doped NTO films, respectively.« less

  8. On the anomalous secular increase of the eccentricity of the orbit of the Moon

    NASA Astrophysics Data System (ADS)

    Iorio, L.

    2011-08-01

    A recent analysis of a Lunar Laser Ranging (LLR) data record spanning 38.7 yr revealed an anomalous increase of the eccentricity e of the lunar orbit amounting to ? yr-1. The present-day models of the dissipative phenomena occurring in the interiors of both the Earth and the Moon are not able to explain it. In this paper, we examine several dynamical effects, not modelled in the data analysis, in the framework of long-range modified models of gravity and of the standard Newtonian/Einsteinian paradigm. It turns out that none of them can accommodate ?. Many of them do not even induce long-term changes in e; other models do, instead, yield such an effect, but the resulting magnitudes are in disagreement with ?. In particular, the general relativistic gravitomagnetic acceleration of the Moon due to the Earth’s angular momentum has the right order of magnitude, but the resulting Lense-Thirring secular effect for the eccentricity vanishes. A potentially viable Newtonian candidate would be a trans-Plutonian massive object (Planet X/Nemesis/Tyche) since it, actually, would affect e with a non-vanishing long-term variation. On the other hand, the values for the physical and orbital parameters of such a hypothetical body required to obtain at least the right order of magnitude for ? are completely unrealistic: suffices it to say that an Earth-sized planet would be at 30 au, while a jovian mass would be at 200 au. Thus, the issue of finding a satisfactorily explanation for the anomalous behaviour of the Moon’s eccentricity remains open.

  9. Anomalous, non-Gaussian tracer diffusion in crowded two-dimensional environments

    NASA Astrophysics Data System (ADS)

    Ghosh, Surya K.; Cherstvy, Andrey G.; Grebenkov, Denis S.; Metzler, Ralf

    2016-01-01

    A topic of intense current investigation pursues the question of how the highly crowded environment of biological cells affects the dynamic properties of passively diffusing particles. Motivated by recent experiments we report results of extensive simulations of the motion of a finite sized tracer particle in a heterogeneously crowded environment made up of quenched distributions of monodisperse crowders of varying sizes in finite circular two-dimensional domains. For given spatial distributions of monodisperse crowders we demonstrate how anomalous diffusion with strongly non-Gaussian features arises in this model system. We investigate both biologically relevant situations of particles released either at the surface of an inner domain or at the outer boundary, exhibiting distinctly different features of the observed anomalous diffusion for heterogeneous distributions of crowders. Specifically we reveal an asymmetric spreading of tracers even at moderate crowding. In addition to the mean squared displacement (MSD) and local diffusion exponent we investigate the magnitude and the amplitude scatter of the time averaged MSD of individual tracer trajectories, the non-Gaussianity parameter, and the van Hove correlation function. We also quantify how the average tracer diffusivity varies with the position in the domain with a heterogeneous radial distribution of crowders and examine the behaviour of the survival probability and the dynamics of the tracer survival probability. Inter alia, the systems we investigate are related to the passive transport of lipid molecules and proteins in two-dimensional crowded membranes or the motion in colloidal solutions or emulsions in effectively two-dimensional geometries, as well as inside supercrowded, surface adhered cells.

  10. What Determines Different Anomalous Transport Behavior in Different Porous Media?

    NASA Astrophysics Data System (ADS)

    Bijeljic, B.; Raeini, A.; Mostaghimi, P.; Blunt, M. J.

    2012-12-01

    Solute transport in porous media is of importance in many scientific fields and applications, notably in contaminant migration in subsurface hydrology, geological storage of carbon-dioxide, packed bed reactors and chromatography in chemical engineering, and tracer studies in enhanced oil recovery. The non-Fickian nature of dispersive processes in heterogeneous media has been demonstrated experimentally from pore to field scales. However, the exact relationship between structure, velocity field and transport has not been fully understood. We study and explain the origin of non-Fickian transport behavior as a function of pore-scale heterogeneity by simulating flow and transport directly on micro-CT images of pore space of the media with increasing pore-scale complexity: beadpack, Bentheimer sandstone and Portland limestone. The Navier-Stokes equations are solved to compute the flow field and the streamline method is used to transport particles by advection, while the random walk method is used for diffusion. The connectivity of the fast flow paths for beadpack, Bentheimer sandstone and Portland carbonate is presented in Figs.1a-c. We show how computed propagators (concentration vs. displacement) for beadpack, sandstone and carbonate depend on the spread in the velocity distribution. A narrow velocity distribution in the beadpack leads to the least anomalous behaviour where the propagators rapidly become Gaussian (Fig.1d); the wider velocity distribution in the sandstone gives rise to a small immobile concentration peak, and a large secondary mobile peak moving at approximately the average flow speed (Fig.1e); in the carbonate with the widest velocity distribution the stagnant concentration peak is persistent, while the emergence of a smaller secondary mobile peak is observed, leading to a highly anomalous behavior (Fig.1f). This defines different generic nature of transport in the three media and quantifies the effect of pore structure on transport. Moreover, the propagators obtained by the model are in a very good agreement with the propagators measured on beadpack, Bentheimer sandstone and Portland carbonate cores in NMR experiments. We discuss the importance of these findings on a suite of six carbonate micro-CT images, classifying them in terms of degree of anomalous transport that can have an impact on the field scale transport.igure 1 Normalized flow fields, presented as the ratios of the magnitude of u at the voxel centers divided by the average flow speed u av for (a) beadpack (b) Bentheimer sandstone and (c) Portland carbonate. Probability of molecular displacement P(ς) in the image as a function of displacement ς at t=2s for (d) beadpack, (e) Bentheimer sandstone, and (f) Portland carbonate. The coordinates are rescaled by the nominal mean displacement <ς> 0 = uavt.

  11. Strong localization induced anomalous temperature dependence exciton emission above 300 K from SnO{sub 2} quantum dots

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pan, S. S., E-mail: sspan@issp.ac.cn, E-mail: ghli@issp.ac.cn; Li, F. D.; Liu, Q. W.

    2015-05-07

    SnO{sub 2} quantum dots (QDs) are potential materials for deep ultraviolet (DUV) light emitting devices. In this study, we report the temperature and excitation power-dependent exciton luminescence from SnO{sub 2} QDs. The exciton emission exhibits anomalous blue shift, accompanied with band width reduction with increasing temperature and excitation power above 300 K. The anomalous temperature dependences of the peak energy and band width are well interpreted by the strongly localized carrier thermal hopping process and Gaussian shape of band tails states, respectively. The localized wells and band tails at conduction minimum are considered to be induced by the surface oxygen defectsmore » and local potential fluctuation in SnO{sub 2} QDs.« less

  12. Anomalous plasma diffusion and the magnetopause boundary layer

    NASA Technical Reports Server (NTRS)

    Treumann, Rudolf A.; Labelle, James; Haerendel, Gerhard; Pottelette, Raymond

    1992-01-01

    An overview of the current state of anomalous diffusion research at the magnetopause and its role in the formation of the magnetopause boundary layer is presented. Plasma wave measurements in the boundary layer indicate that most of the relevant unstable wave modes contribute negligibly to the diffusion process at the magnetopause under magnetically undisturbed northward IMF conditions. The most promising instability is the lower hybrid drift instability, which may yield diffusion coefficients of the right order if the highest measured wave intensities are assumed. It is concluded that global stationary diffusion due to wave-particle interactions does not take place at the magnetopause. Microscopic wave-particle interaction and anomalous diffusion may contribute to locally break the MD frozen-in conditions and help in transporting large amounts of magnetosheath plasma across the magnetospheric boundary.

  13. Anomalous high-frequency wave activity flux preceding anomalous changes in the Northern polar jet

    NASA Astrophysics Data System (ADS)

    Nakamura, Mototaka; Kadota, Minoru; Yamane, Shozo

    2010-05-01

    Anomalous forcing by quasi-geostrophic (QG) waves has been reported as an important forcing factor in the Northern Annular Mode (NAM) in recent literatures. In order to shed a light on the dynamics of the NAM from a different angle, we have examined anomalous behavior of the winter jets in the upper troposphere and stratosphere by focusing our diagnosis on not the anomalous geopotential height (Z) itself, but on the anomalous change in the Z (dZ) between two successive months and preceding transient QG wave activity flux during the cold season. We calculated EOFs of dZ between two successive months at 150hPa for a 46-year period, from 1958 to 2003, using the monthly mean NCEP reanalysis data. We then formed anomaly composites of changes in Z and the zonal velocity (U), as well as the preceding and following wave activity flux, Z, U, and temperature at various heights, for both positive and negative phases of the first EOF. For the wave forcing fields, we adopted the diagnostic system for the three-dimensional QG transient wave activity flux in the zonally-varying three-dimensional mean flow developed by Plumb (1986) with a slight modification in its application to the data. Our choice of the Plumb86 is based on the fact that the winter mean flow in the Northern Hemisphere is characterized by noticeable zonal asymmetry, and has a symbiotic relationship with waves in the extra-tropics. The Plumb86 flux was calculated for high-frequency (period of 2 to 7 days) and low-frequency (period of 10 to 20 days) waves with the ultra-low-frequency (period of 30 days or longer) flow as the reference state for each time frame of the 6 hourly NCEP reanalysis data from 1958 to 2003. By replacing the mean flow with the ultra-low-frequency flow in the application of the Plumb86 formula, the flux fields were calculated as time series at 6 hour intervals. The time series of the wave activity flux was then averaged for each month. The patterns of composited anomalous dZ and dU clearly show anomalous acceleration or deceleration of U in the polar region, accompanied by anomalies of the opposite sign in the subtropics throughout the troposphere and stratosphere. The anomalies are conspicuously large in the polar stratosphere. The composited anomalous Z and U in the preceding and following months indicate that these large anomalies in dZ and dU occur when the polar troposphere and stratosphere are relaxing back toward the climatology from strongly anomalous states that closely resemble the positive and negative phases of the NAM. In this process of relaxation, the atmosphere actually overshoots the climatology and develops anomalies of the sign opposite to those existed initially. The anomalous wave activity flux exhibit strong signals of anomalous upward (downward) propagation of high-frequency waves in the North Atlantic storm track from the bottom of the atmosphere, penetrating up to the stratosphere, when the polar jet is anomalously strong (weak) in the preceding month. The anomalous horizontal wave activity flux shows anomalous eastward (westward) flux emanating from the North Atlantic storm track when the polar jet is anomalously strong (weak) in the preceding month. These patterns suggest that anomalous high-frequency waves originating from the North Atlantic storm track in the lower troposphere contribute to the destruction of both phases of the NAM. However, the anomalous flux divergence is very noisy everywhere due to the noisiness of the advective horizontal flux, making it difficult to ascertain the role of the high-frequency transients in the destruction of the NAM.

  14. Experimental evidence for the lattice instability of Bi-based superconducting systems

    NASA Astrophysics Data System (ADS)

    Yusheng, He; Jiong, Xiang; Hsin, Wang; Aisheng, He; Jincang, Zhang; Fanggao, Chang

    1989-11-01

    Ultrasonic measurements, specific heat and thermal analysis experiments, X-ray diffraction study and infrared investigation revealed that there are anomalous structural changes or lattice instabilities near 200 K in single 2212 or 2223 phase samples of Bi(Pb)-Sr-Ca-Cu-O system. Detailed study showed that anomalous changes or lattice instabilities are isothermal-like processes and have the characteristics of a structural phase transition, accompanying with increases in lattice constants. Possible mechanism for this lattice instability is discussed.

  15. Extracting the chiral anomaly from γπ→ππ

    NASA Astrophysics Data System (ADS)

    Hoferichter, Martin; Kubis, Bastian; Sakkas, Dimitrios

    2012-12-01

    We derive dispersive representations for the anomalous process γπ→ππ with the ππ P-wave phase shift as input. We investigate how in this framework the chiral anomaly can be extracted from a cross-section measurement using all data up to 1 GeV, and discuss the importance of a precise representation of the γπ→ππ amplitude for the hadronic light-by-light contribution to the anomalous magnetic moment of the muon.

  16. Feynman-Kac equations for reaction and diffusion processes

    NASA Astrophysics Data System (ADS)

    Hou, Ru; Deng, Weihua

    2018-04-01

    This paper provides a theoretical framework for deriving the forward and backward Feynman-Kac equations for the distribution of functionals of the path of a particle undergoing both diffusion and reaction processes. Once given the diffusion type and reaction rate, a specific forward or backward Feynman-Kac equation can be obtained. The results in this paper include those for normal/anomalous diffusions and reactions with linear/nonlinear rates. Using the derived equations, we apply our findings to compute some physical (experimentally measurable) statistics, including the occupation time in half-space, the first passage time, and the occupation time in half-interval with an absorbing or reflecting boundary, for the physical system with anomalous diffusion and spontaneous evanescence.

  17. Importance of mechanical disaggregation in chemical weathering in a cold alpine environment, San Juan Mountains, Colorado

    USGS Publications Warehouse

    Hoch, A.R.; Reddy, M.M.; Drever, J.I.

    1999-01-01

    Weathering of welded tuff near the summit of Snowshoe Mountain (3660 m) in southwestern Colorado was studied by analyzing infiltrating waters in the soil and associated solid phases. Infiltrating waters exhibit anomalously high potassium to silica ratios resulting from dissolution of a potassium-rich glass that occurs as a trace phase in the rock. In laboratory experiments using rock from the field site, initial dissolution generated potassium-rich solutions similar to those observed in the field. The anomalous potassium release decreased over time (about 1 month), after which the dominant cation was calcium, with a much lower potassium to silica ratio. The anomalous potassium concentrations observed in the infiltrating soil solutions result from weathering of freshly exposed rock surfaces. Continual mechanical disaggregation of the rock due to segregation freezing exposes fresh glass to weathering and thus maintains the source of potassium for the infiltrating water. The ongoing process of creation of fresh surfaces by physical processes is an important influence on the composition of infiltrating waters in the vadose zone.

  18. Adaptive Gaussian mixture models for pre-screening in GPR data

    NASA Astrophysics Data System (ADS)

    Torrione, Peter; Morton, Kenneth, Jr.; Besaw, Lance E.

    2011-06-01

    Due to the large amount of data generated by vehicle-mounted ground penetrating radar (GPR) antennae arrays, advanced feature extraction and classification can only be performed on a small subset of data during real-time operation. As a result, most GPR based landmine detection systems implement "pre-screening" algorithms to processes all of the data generated by the antennae array and identify locations with anomalous signatures for more advanced processing. These pre-screening algorithms must be computationally efficient and obtain high probability of detection, but can permit a false alarm rate which might be higher than the total system requirements. Many approaches to prescreening have previously been proposed, including linear prediction coefficients, the LMS algorithm, and CFAR-based approaches. Similar pre-screening techniques have also been developed in the field of video processing to identify anomalous behavior or anomalous objects. One such algorithm, an online k-means approximation to an adaptive Gaussian mixture model (GMM), is particularly well-suited to application for pre-screening in GPR data due to its computational efficiency, non-linear nature, and relevance of the logic underlying the algorithm to GPR processing. In this work we explore the application of an adaptive GMM-based approach for anomaly detection from the video processing literature to pre-screening in GPR data. Results with the ARA Nemesis landmine detection system demonstrate significant pre-screening performance improvements compared to alternative approaches, and indicate that the proposed algorithm is a complimentary technique to existing methods.

  19. Anomalous visual experiences, negative symptoms, perceptual organization and the magnocellular pathway in schizophrenia: a shared construct?

    PubMed

    Kéri, Szabolcs; Kiss, Imre; Kelemen, Oguz; Benedek, György; Janka, Zoltán

    2005-10-01

    Schizophrenia is associated with impaired visual information processing. The aim of this study was to investigate the relationship between anomalous perceptual experiences, positive and negative symptoms, perceptual organization, rapid categorization of natural images and magnocellular (M) and parvocellular (P) visual pathway functioning. Thirty-five unmedicated patients with schizophrenia and 20 matched healthy control volunteers participated. Anomalous perceptual experiences were assessed with the Bonn Scale for the Assessment Basic Symptoms (BSABS). General intellectual functions were evaluated with the revised version of the Wechsler Adult Intelligence Scale. The 1-9 version of the Continuous Performance Test (CPT) was used to investigate sustained attention. The following psychophysical tests were used: detection of Gabor patches with collinear and orthogonal flankers (perceptual organization), categorization of briefly presented natural scenes (rapid visual processing), low-contrast and frequency-doubling vernier threshold (M pathway functioning), isoluminant colour vernier threshold and high spatial frequency discrimination (P pathway functioning). The patients with schizophrenia were impaired on test of perceptual organization, rapid visual processing and M pathway functioning. There was a significant correlation between BSABS scores, negative symptoms, perceptual organization, rapid visual processing and M pathway functioning. Positive symptoms, IQ, CPT and P pathway measures did not correlate with these parameters. The best predictor of the BSABS score was the perceptual organization deficit. These results raise the possibility that multiple facets of visual information processing deficits can be explained by M pathway dysfunctions in schizophrenia, resulting in impaired attentional modulation of perceptual organization and of natural image categorization.

  20. Low temperature internal friction spectrum of YBa 2Cu 3O x

    NASA Astrophysics Data System (ADS)

    Mi, Y.; Schaller, R.; Berger, H.; Benoit, W.; Sathish, S.

    1991-01-01

    The elastic and anelastic behaviours of polycrystalline YBa 2Cu 3O x specimens have been studied between 80 and 300 K, by means of a resonant bar technique. Three damping peaks have been observed at 90, 115 and 220 K. The stability of these peaks during annealing in vacuum has been carefully examined. The 90 K peak is not related to the superconducting transition because it is still observed after thermal treatments leading to the disappearance of superconductivity. The 115 K is due to a relaxation mechanism. The activation energy is ∼0.17 eV and the frequency factor is ∼10 12s -1. Also this peak is certainly correlated with the excess oxygen atoms, because it disappears with annealing in vacuum. The 220 K maximum, which was also observed by ultrasonic measurements, seems to be affected by the sample preparation, i.e. by the sintering conditions. Finally, a frequency hysteresis has been observed in every superconducting sample, which accounts for an anomalous behaviour of the elastic modulus.

  1. Anomalous polymer collapse winding angle distributions

    NASA Astrophysics Data System (ADS)

    Narros, A.; Owczarek, A. L.; Prellberg, T.

    2018-03-01

    In two dimensions polymer collapse has been shown to be complex with multiple low temperature states and multi-critical points. Recently, strong numerical evidence has been provided for a long-standing prediction of universal scaling of winding angle distributions, where simulations of interacting self-avoiding walks show that the winding angle distribution for N-step walks is compatible with the theoretical prediction of a Gaussian with a variance growing asymptotically as Clog N . Here we extend this work by considering interacting self-avoiding trails which are believed to be a model representative of some of the more complex behaviour. We provide robust evidence that, while the high temperature swollen state of this model has a winding angle distribution that is also Gaussian, this breaks down at the polymer collapse point and at low temperatures. Moreover, we provide some evidence that the distributions are well modelled by stretched/compressed exponentials, in contradistinction to the behaviour found in interacting self-avoiding walks. Dedicated to Professor Stu Whittington on the occasion of his 75th birthday.

  2. H-modulated microwave absorption and resistive transition in the high- Tc superconductor YBa 2Cu 3O 7

    NASA Astrophysics Data System (ADS)

    Buluggiu, E.; Vera, A.; Amoretti, G.

    1990-11-01

    The derivative microwave absorption near Tc in presence of a sufficiently high field ( H⩾1 kOe) is related to the temperature variation of resistivity. This idea, originally proposed by Kim et al. (1988), is extended to take into account the effects of the anomalous resistive tail by using the thermoactivated flux-creep model proposed by Tinkham (1988). This gives a simple explanation for some relevant features observed in the temperature behaviour of the ESR absorption, as the asymmetry of the peak at Tc, with the long tail extending toward low temperatures, and the field dependence of height and linewidth, for which the model provides H-1 and H2/3 behaviour, respectively, ESR data on YBa 2Cu 3O 7 powder are in satisfactory agreement with this picture, when the role of the intrinsic 2D-character of this compound is properly taken into account. This allows us to deduce consistent values for the parameters a‖ and a⊥ of the anisotropic resistivity.

  3. Low percolation transitions in carbon nanotube networks dispersed in a polymer matrix: dielectric properties, simulations and experiments.

    PubMed

    Simoes, Ricardo; Silva, Jaime; Vaia, Richard; Sencadas, Vítor; Costa, Pedro; Gomes, João; Lanceros-Méndez, Senentxu

    2009-01-21

    The low concentration behaviour and the increase of the dielectric constant in carbon nanotubes/polymer nanocomposites near the percolation threshold are still not well understood. In this work, a numerical model has been developed which focuses on the effect of the inclusion of conductive fillers in a dielectric polymer matrix on the dielectric constant and the dielectric strength. Experiments have been carried out in carbon nanotubes/poly(vinylidene fluoride) nanocomposites in order to compare to the simulation results. This work shows how the critical concentration is related to the formation of capacitor networks and that these networks give rise to high variations in the electrical properties of the composites. Based on numerical studies, the dependence of the percolation transition on the preparation of the nanocomposite is discussed. Finally, based on numerical and experimental results, both ours and from other authors, the causes of anomalous percolation behaviour of the dielectric constant are identified.

  4. Methane seep carbonates yield clumped isotope signatures out of equilibrium with formation temperatures

    DOE PAGES

    Loyd, S. J.; Sample, J.; Tripati, R. E.; ...

    2016-07-22

    Here, methane cold seep systems typically exhibit extensive buildups of authigenic carbonate minerals, resulting from local increases in alkalinity driven by methane oxidation. Here, we demonstrate that modern seep authigenic carbonates exhibit anomalously low clumped isotope values (Δ47), as much as ~0.2‰ lower than expected values. In modern seeps, this range of disequilibrium translates into apparent temperatures that are always warmer than ambient temperatures, by up to 50 °C. We examine various mechanisms that may induce disequilibrium behaviour in modern seep carbonates, and suggest that the observed values result from several factors including kinetic isotopic effects during methane oxidation, mixingmore » of inorganic carbon pools, pH effects and rapid precipitation. Ancient seep carbonates studied here also exhibit potential disequilibrium signals. Ultimately, these findings indicate the predominance of disequilibrium clumped isotope behaviour in modern cold seep carbonates that must be considered when characterizing environmental conditions in both modern and ancient cold seep settings.« less

  5. Cows Come Down from the Mountains before the (Mw = 6.1) Earthquake Colfiorito in September 1997; A Single Case Study.

    PubMed

    Fidani, Cristiano; Freund, Friedemann; Grant, Rachel

    2014-06-03

    The September-October 1997 seismic sequence in the Umbria-Marche regions of Central Italy has been one of the stronger seismic events to occur in Italy over the last thirty years, with a maximum magnitude of Mw = 6.1. Over the last three years, a collection of evidence was carried out regarding non-seismic phenomena, by interviewing local residents using a questionnaire. One particular observation of anomalous animal behaviour, confirmed by many witnesses, concerned a herd of cows, which descended from a mountain close to the streets of a village near the epicentre, a few days before the main shock. Testimonies were collected using a specific questionnaire including data on earthquake lights, spring variations, human diseases, and irregular animal behaviour. The questionnaire was compiled after the L'Aquila earthquake in 2009, and was based upon past historical earthquake observations. A possible explanation for the cows' behavior-local air ionization caused by stress-activated positive holes-is discussed.

  6. Weak ergodicity breaking, irreproducibility, and ageing in anomalous diffusion processes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Metzler, Ralf

    2014-01-14

    Single particle traces are standardly evaluated in terms of time averages of the second moment of the position time series r(t). For ergodic processes, one can interpret such results in terms of the known theories for the corresponding ensemble averaged quantities. In anomalous diffusion processes, that are widely observed in nature over many orders of magnitude, the equivalence between (long) time and ensemble averages may be broken (weak ergodicity breaking), and these time averages may no longer be interpreted in terms of ensemble theories. Here we detail some recent results on weakly non-ergodic systems with respect to the time averagedmore » mean squared displacement, the inherent irreproducibility of individual measurements, and methods to determine the exact underlying stochastic process. We also address the phenomenon of ageing, the dependence of physical observables on the time span between initial preparation of the system and the start of the measurement.« less

  7. Low-temperature thermal conductivity of ferroelastic Gd 2(MoO 4) 3

    NASA Astrophysics Data System (ADS)

    Mielcarek, S.; Mróz, B.; Tylczyński, Z.; Piskunowicz, P.; Trybuła, Z.; Bromberek, M.

    2001-05-01

    Thermal conductivity, k, of GMO crystal has been measured in temperatures from 0.5 to 80 K. The maximum of k appears at 18 K and its value depends on the current domain state of the sample. The ferroelastic domain walls and antiphase boundaries, characterised by elastic inhomogeneities, are responsible for additional phonon scattering and a decrease in the thermal conductivity. The deviation of the temperature dependence of thermal conductivity from the classical Debye theory observed below 4 K is related to the anomalous behaviour of specific heat in the region of the antiferromagnetic transition at T N=0.3 K .

  8. Time to Go Beyond Triple-Gauge-Boson-Coupling Interpretation of W Pair Production.

    PubMed

    Zhang, Zhengkang

    2017-01-06

    W boson pair production processes at e^{+}e^{-} and pp colliders have been conventionally interpreted as measurements of WWZ and WWγ triple gauge couplings (TGCs). Such an interpretation is based on the assumption that new physics effects other than anomalous TGCs are negligible. While this "TGC dominance assumption" was well motivated and useful at LEP2 thanks to precision electroweak constraints, it is already challenged by recent LHC data. In fact, contributions from anomalous Z boson couplings that are allowed by electroweak precision data but neglected in LHC analyses, which are enhanced at high energy, can even dominate over those from the anomalous TGCs considered. This limits the generality of the anomalous TGC constraints derived in current analyses and necessitates extension of the analysis framework and a change of physics interpretation. The issue will persist as we continue to explore the high-energy frontier. We clarify and analyze the situation in the effective field theory framework, which provides a useful organizing principle for understanding standard model deviations in the high-energy regime.

  9. A Study Of Anomalous Stars and Binary Populations Within Open Clusters: Tests Of Theoretical Models

    NASA Astrophysics Data System (ADS)

    Geller, Aaron M.; Mathieu, Robert D.; Braden, Ella; Latham, David W.

    2008-08-01

    ``Anomalous'' stars, such as blue stragglers and more recently sub- subgiants, have been an enduring challenge for stellar evolution theory. Recently it has become clear that in star clusters these systems are closely linked to the binary star populations. Furthermore, through advances in N-body modeling, we have come to realize that stellar dynamical processes play a central role in the formation of such anomalous stars. Indeed, these stars trace the interface between the classical fields of stellar evolution and stellar dynamics. We propose a thesis study to directly probe this interface through high-precision radial-velocity measurements of the anomalous stars and the binary populations in four open clusters. We have selected NGC 188 (7 Gyr), M67 (NGC 2682; 4 Gyr), NGC 6819 (2.4 Gyr), and M35 (NGC 2168; 150 Myr), as these span a wide range in age, are rich enough to provide statistically significant conclusions, and already have an extensive base of kinematic, spectroscopic, and photometric observations from the WIYN Open Cluster Study. Our proposed observations will define the spectroscopic hard binary populations (fraction, frequency distributions of orbital parameters, mass ratios) for orbital periods approaching the hard-soft boundary. These observations will also provide a comprehensive survey for anomalous stars, including secure establishment of their cluster membership. These data will allow us to perform the first detailed comparison to predictions from open cluster simulations of the binary populations among normal and anomalous stars, and thereby to constrain the evolutionary paths from one to the other.

  10. A Study Of Anomalous Stars and Binary Populations Within Open Clusters: Tests Of Theoretical Models

    NASA Astrophysics Data System (ADS)

    Geller, Aaron M.; Mathieu, Robert D.; Gosnell, Natalie; Latham, David W.

    2009-02-01

    ``Anomalous'' stars, such as blue stragglers and more recently sub- subgiants, have been an enduring challenge for stellar evolution theory. Recently it has become clear that in star clusters these systems are closely linked to the binary star populations. Furthermore, through advances in N-body modeling, we have come to realize that stellar dynamical processes play a central role in the formation of such anomalous stars. Indeed, these stars trace the interface between the classical fields of stellar evolution and stellar dynamics. We propose a thesis study to directly probe this interface through high-precision radial-velocity measurements of the anomalous stars and the binary populations in four open clusters. We have selected NGC 188 (7 Gyr), M67 (NGC 2682; 4 Gyr), NGC 6819 (2.4 Gyr), and M35 (NGC 2168; 150 Myr), as these span a wide range in age, are rich enough to provide statistically significant conclusions, and already have an extensive base of kinematic, spectroscopic, and photometric observations from the WIYN Open Cluster Study. Our proposed observations will define the spectroscopic hard binary populations (fraction, frequency distributions of orbital parameters, mass ratios) for orbital periods approaching the hard-soft boundary. These observations will also provide a comprehensive survey for anomalous stars, including secure establishment of their cluster membership. These data will allow us to perform the first detailed comparison to predictions from open cluster simulations of the binary populations among normal and anomalous stars, and thereby to constrain the evolutionary paths from one to the other.

  11. A Study Of Anomalous Stars and Binary Populations Within Open Clusters: Tests Of Theoretical Models

    NASA Astrophysics Data System (ADS)

    Geller, Aaron M.; Mathieu, Robert D.; Braden, Ella; Latham, David W.

    2008-02-01

    ``Anomalous'' stars, such as blue stragglers and more recently sub- subgiants, have been an enduring challenge for stellar evolution theory. Recently it has become clear that in star clusters these systems are closely linked to the binary star populations. Furthermore, through advances in N-body modeling, we have come to realize that stellar dynamical processes play a central role in the formation of such anomalous stars. Indeed, these stars trace the interface between the classical fields of stellar evolution and stellar dynamics. We propose a thesis study to directly probe this interface through high-precision radial-velocity measurements of the anomalous stars and the binary populations in four open clusters. We have selected NGC 188 (7 Gyr), M67 (NGC 2682; 4 Gyr), NGC 6819 (2.4 Gyr), and M35 (NGC 2168; 150 Myr), as these span a wide range in age, are rich enough to provide statistically significant conclusions, and already have an extensive base of kinematic, spectroscopic, and photometric observations from the WIYN Open Cluster Study. Our proposed observations will define the spectroscopic hard binary populations (fraction, frequency distributions of orbital parameters, mass ratios) for orbital periods approaching the hard-soft boundary. These observations will also provide a comprehensive survey for anomalous stars, including secure establishment of their cluster membership. These data will allow us to perform the first detailed comparison to predictions from open cluster simulations of the binary populations among normal and anomalous stars, and thereby to constrain the evolutionary paths from one to the other.

  12. Stochastic tools hidden behind the empirical dielectric relaxation laws

    NASA Astrophysics Data System (ADS)

    Stanislavsky, Aleksander; Weron, Karina

    2017-03-01

    The paper is devoted to recent advances in stochastic modeling of anomalous kinetic processes observed in dielectric materials which are prominent examples of disordered (complex) systems. Theoretical studies of dynamical properties of ‘structures with variations’ (Goldenfield and Kadanoff 1999 Science 284 87-9) require application of such mathematical tools—by means of which their random nature can be analyzed and, independently of the details distinguishing various systems (dipolar materials, glasses, semiconductors, liquid crystals, polymers, etc), the empirical universal kinetic patterns can be derived. We begin with a brief survey of the historical background of the dielectric relaxation study. After a short outline of the theoretical ideas providing the random tools applicable to modeling of relaxation phenomena, we present probabilistic implications for the study of the relaxation-rate distribution models. In the framework of the probability distribution of relaxation rates we consider description of complex systems, in which relaxing entities form random clusters interacting with each other and single entities. Then we focus on stochastic mechanisms of the relaxation phenomenon. We discuss the diffusion approach and its usefulness for understanding of anomalous dynamics of relaxing systems. We also discuss extensions of the diffusive approach to systems under tempered random processes. Useful relationships among different stochastic approaches to the anomalous dynamics of complex systems allow us to get a fresh look at this subject. The paper closes with a final discussion on achievements of stochastic tools describing the anomalous time evolution of complex systems.

  13. Psychological interventions for adults who have sexually offended or are at risk of offending.

    PubMed

    Dennis, Jane A; Khan, Omer; Ferriter, Michael; Huband, Nick; Powney, Melanie J; Duggan, Conor

    2012-12-12

    Sexual offending is a legal construct that overlaps, but is not entirely congruent with, clinical constructs of disorders of sexual preference. Sexual offending is both a social and a public health issue. Victim surveys illustrate high incidence and prevalence levels, and it is commonly accepted that there is considerable hidden sexual victimisation. There are significant levels of psychiatric morbidity in survivors of sexual offences.Psychological interventions are generally based on behavioural or psychodynamic theories.Behavioural interventions fall into two main groups: those based on traditional classical conditioning and/or operant learning theory and those based on cognitive behavioural approaches. Approaches may overlap. Interventions associated with traditional classical and operant learning theory are referred to as behaviour modification or behaviour therapy, and focus explicitly on changing behaviour by administering a stimulus and measuring its effect on overt behaviour. Within sex offender treatment, examples include aversion therapy, covert sensitisation or olfactory conditioning. Cognitive behavioural therapies are intended to change internal processes - thoughts, beliefs, emotions, physiological arousal - alongside changing overt behaviour, such as social skills or coping behaviours. They may involve establishing links between offenders' thoughts, feelings and actions about offending behaviour; correction of offenders' misperceptions, irrational beliefs and reasoning biases associated with their offending; teaching offenders to monitor their own thoughts, feelings and behaviours associated with offending; and promoting alternative ways of coping with deviant sexual thoughts and desires.Psychodynamic interventions share a common root in psychoanalytic theory. This posits that sexual offending arises through an imbalance of the three components of mind: the id, the ego and the superego, with sexual offenders having temperamental imbalance of a powerful id (increased sexual impulses and libido) and a weak superego (a low level of moral probation), which are also impacted by early environment.This updates a previous Cochrane review but is based on a new protocol. To assess the effects of psychological interventions on those who have sexually offended or are at risk of offending. In September 2010 we searched: CENTRAL, MEDLINE, Allied and Complementary Medicine (AMED), Applied Social Sciences Index and Abstracts (ASSIA), Biosis Previews, CINAHL, COPAC, Dissertation Abstracts, EMBASE, International Bibliography of the Social Sciences (IBSS), ISI Proceedings, Science Citation Index Expanded (SCI), Social Sciences Citation Index (SSCI), National Criminal Justice Reference Service Abstracts Database, PsycINFO, OpenSIGLE, Social Care Online, Sociological Abstracts, UK Clinical Research Network Portfolio Database and ZETOC. We contacted numerous experts in the field. Randomised trials comparing psychological intervention with standard care or another psychological therapy given to adults treated in institutional or community settings for sexual behaviours that have resulted in conviction or caution for sexual offences, or who are seeking treatment voluntarily for behaviours classified as illegal. At least two authors, working independently, selected studies, extracted data and assessed the studies' risk of bias. We contacted study authors for additional information including details of methods and outcome data. We included ten studies involving data from 944 adults, all male.Five trials involved primarily cognitive behavioural interventions (CBT) (n = 664). Of these, four compared CBT with no treatment or wait list control, and one compared CBT with standard care. Only one study collected data on the primary outcome. The largest study (n = 484) involved the most complex intervention versus no treatment. Long-term outcome data are reported for groups in which the mean years 'at risk' in the community are similar (8.3 years for treatment (n = 259) compared to 8.4 in the control group (n = 225)). There was no difference between these groups in terms of the risk of reoffending as measured by reconviction for sexual offences (risk ratio (RR) 1.10; 95% CI 0.78 to 1.56).Four trials (n = 70) compared one behavioural programme with an alternative behavioural programme or with wait list control. No meta-analysis was possible for this comparison. For two studies (both cross-over, n = 29) no disaggregated data were available. The remaining two behavioural studies compared imaginal desensitisation with either covert sensitisation or as part of adjunctive drug therapy (n = 20 and 21, respectively). In these two studies, results for the primary outcome (being 'charged with anomalous behaviour') were encouraging, with only one new charge for the treated groups over one year in the former study, and in the latter study, only one new charge (in the drug-only group) over two years.One study compared psychodynamic intervention with probation. Results for this study (n = 231) indicate a slight trend in favour of the control group (probation) over the intervention (group therapy) in terms of sexual offending as measured by rearrest (RR 1.87; 95% CI 0.78 to 4.47) at 10-year follow-up.Data for adverse events, 'sexually anomalous urges' and for secondary outcomes thought to be 'dynamic' risk factors for reoffending, including anger and cognitive distortions, were limited. The inescapable conclusion of this review is the need for further randomised controlled trials. While we recognise that randomisation is considered by some to be unethical or politically unacceptable (both of which are based on the faulty premise that the experimental treatment is superior to the control - this being the point of the trial to begin with), without such evidence, the area will fail to progress. Not only could this result in the continued use of ineffective (and potentially harmful) interventions, but it also means that society is lured into a false sense of security in the belief that once the individual has been treated, their risk of reoffending is reduced. Current available evidence does not support this belief. Future trials should concentrate on minimising risk of bias, maximising quality of reporting and including follow-up for a minimum of five years 'at risk' in the community.

  14. Random walks exhibiting anomalous diffusion: elephants, urns and the limits of normality

    NASA Astrophysics Data System (ADS)

    Kearney, Michael J.; Martin, Richard J.

    2018-01-01

    A random walk model is presented which exhibits a transition from standard to anomalous diffusion as a parameter is varied. The model is a variant on the elephant random walk and differs in respect of the treatment of the initial state, which in the present work consists of a given number N of fixed steps. This also links the elephant random walk to other types of history dependent random walk. As well as being amenable to direct analysis, the model is shown to be asymptotically equivalent to a non-linear urn process. This provides fresh insights into the limiting form of the distribution of the walker’s position at large times. Although the distribution is intrinsically non-Gaussian in the anomalous diffusion regime, it gradually reverts to normal form when N is large under quite general conditions.

  15. Origin of resistivity in reconnection

    NASA Astrophysics Data System (ADS)

    Treumann, Rudolf A.

    2001-06-01

    Resistivity is believed to play an important role in reconnection leading to the distinction between resistive and collisionless reconnection. The former is treated in the Sweet-Parker model of long current sheets, and the Petschek model of a small resistive region. Both models in spite of their different dynamics attribute to the violation of the frozen-in condition in their diffusion regions due to the action of resistivity. In collisionless reconnection there is little consensus about the processes breaking the frozen-in condition. The question is whether anomalous processes generate sufficient resistivity or whether other processes free the particles from slavery by the magnetic field. In the present paper we review processes that may cause anomalous resistivity in collisionless current sheets. Our general conclusion is that in space plasma boundaries accessible to in situ spacecraft, wave levels have always been found to be high enough to explain the existence of large enough local diffusivity for igniting local reconnection. However, other processes might take place as well. Non-resistive reconnection can be caused by inertia or diamagnetism.

  16. Anomalous versus Slowed-Down Brownian Diffusion in the Ligand-Binding Equilibrium

    PubMed Central

    Soula, Hédi; Caré, Bertrand; Beslon, Guillaume; Berry, Hugues

    2013-01-01

    Measurements of protein motion in living cells and membranes consistently report transient anomalous diffusion (subdiffusion) that converges back to a Brownian motion with reduced diffusion coefficient at long times after the anomalous diffusion regime. Therefore, slowed-down Brownian motion could be considered the macroscopic limit of transient anomalous diffusion. On the other hand, membranes are also heterogeneous media in which Brownian motion may be locally slowed down due to variations in lipid composition. Here, we investigate whether both situations lead to a similar behavior for the reversible ligand-binding reaction in two dimensions. We compare the (long-time) equilibrium properties obtained with transient anomalous diffusion due to obstacle hindrance or power-law-distributed residence times (continuous-time random walks) to those obtained with space-dependent slowed-down Brownian motion. Using theoretical arguments and Monte Carlo simulations, we show that these three scenarios have distinctive effects on the apparent affinity of the reaction. Whereas continuous-time random walks decrease the apparent affinity of the reaction, locally slowed-down Brownian motion and local hindrance by obstacles both improve it. However, only in the case of slowed-down Brownian motion is the affinity maximal when the slowdown is restricted to a subregion of the available space. Hence, even at long times (equilibrium), these processes are different and exhibit irreconcilable behaviors when the area fraction of reduced mobility changes. PMID:24209851

  17. Complex quantum transport in a modulation doped strained Ge quantum well heterostructure with a high mobility 2D hole gas

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Morrison, C., E-mail: c.morrison.2@warwick.ac.uk; Casteleiro, C.; Leadley, D. R.

    The complex quantum transport of a strained Ge quantum well (QW) modulation doped heterostructure with two types of mobile carriers has been observed. The two dimensional hole gas (2DHG) in the Ge QW exhibits an exceptionally high mobility of 780 000 cm{sup 2}/Vs at temperatures below 10 K. Through analysis of Shubnikov de-Haas oscillations in the magnetoresistance of this 2DHG below 2 K, the hole effective mass is found to be 0.065 m{sub 0}. Anomalous conductance peaks are observed at higher fields which deviate from standard Shubnikov de-Haas and quantum Hall effect behaviour due to conduction via multiple carrier types. Despite this complex behaviour,more » analysis using a transport model with two conductive channels explains this behaviour and allows key physical parameters such as the carrier effective mass, transport, and quantum lifetimes and conductivity of the electrically active layers to be extracted. This finding is important for electronic device applications, since inclusion of highly doped interlayers which are electrically active, for enhancement of, for example, room temperature carrier mobility, does not prevent analysis of quantum transport in a QW.« less

  18. High Pressure Experimental Studies on CuO: Indication of Re-entrant Multiferroicity at Room Temperature

    PubMed Central

    Jana, Rajesh; Saha, Pinku; Pareek, Vivek; Basu, Abhisek; Kapri, Sutanu; Bhattacharyya, Sayan; Mukherjee, Goutam Dev

    2016-01-01

    We have carried out detailed experimental investigations on polycrystalline CuO using dielectric constant, dc resistance, Raman spectroscopy and X-ray diffraction measurements at high pressures. Observation of anomalous changes both in dielectric constant and dielectric loss in the pressure range 3.7–4.4 GPa and reversal of piezoelectric current with reversal of poling field direction indicate to a change in ferroelectric order in CuO at high pressures. A sudden jump in Raman integrated intensity of Ag mode at 3.4 GPa and observation of Curie-Weiss type behaviour in dielectric constant below 3.7 GPa lends credibility to above ferroelectric transition. A slope change in the linear behaviour of the Ag mode and a minimum in the FWHM of the same indicate indirectly to a change in magnetic ordering. Since all the previous studies show a strong spin-lattice interaction in CuO, observed change in ferroic behaviour at high pressures can be related to a reentrant multiferroic ordering in the range 3.4 to 4.4 GPa, much earlier than predicted by theoretical studies. We argue that enhancement of spin frustration due to anisotropic compression that leads to change in internal lattice strain brings the multiferroic ordering to room temperature at high pressures. PMID:27530329

  19. Decision-making during gambling: an integration of cognitive and psychobiological approaches

    PubMed Central

    Clark, Luke

    2010-01-01

    Gambling is a widespread form of entertainment that may afford unique insights into the interaction between cognition and emotion in human decision-making. It is also a behaviour that can become harmful, and potentially addictive, in a minority of individuals. This article considers the status of two dominant approaches to gambling behaviour. The cognitive approach has identified a number of erroneous beliefs held by gamblers, which cause them to over-estimate their chances of winning. The psychobiological approach has examined case-control differences between groups of pathological gamblers and healthy controls, and has identified dysregulation of brain areas linked to reward and emotion, including the ventromedial prefrontal cortex (vmPFC) and striatum, as well as alterations in dopamine neurotransmission. In integrating these two approaches, recent data are discussed that reveal anomalous recruitment of the brain reward system (including the vmPFC and ventral striatum) during two common cognitive distortions in gambling games: the near-miss effect and the effect of personal control. In games of chance, near-misses and the presence of control have no objective influence on the likelihood of winning. These manipulations appear to harness a reward system that evolved to learn skill-oriented behaviours, and by modulating activity in this system, these cognitive distortions may promote continued, and potentially excessive, gambling. PMID:20026469

  20. Leachate flow around a well in MSW landfill: Analysis of field tests using Richards model.

    PubMed

    Slimani, R; Oxarango, L; Sbartai, B; Tinet, A-J; Olivier, F; Dias, D

    2017-05-01

    During the lifespan of a Municipal Solid Waste landfill, its leachate drainage system may get clogged. Then, as a consequence of rainfall, leachate generation and possibly leachate injection, the moisture content in the landfill increases to the point that a leachate mound could be created. Therefore, pumping the leachate becomes a necessary solution. This paper presents an original analysis of leachate pumping and injection in an instrumented well. The water table level around the well is monitored by nine piezometers which allow the leachate flow behaviour to be captured. A numerical model based on Richards equation and an exponential relationship between saturated hydraulic conductivity and depth is used to analyze the landfill response to pumping and injection. Decreasing permeability with depth appears to have a major influence on the behaviour of the leachate flow. It could have a drastic negative impact on the pumping efficiency with a maximum quasi-stationary pumping rate limited to approximately 1m 3 /h for the tested well and the radius of influence is less than 20m. The numerical model provides a reasonable description of both pumping and injection tests. However, an anomalous behaviour observed at the transition between pumping and recovery phases is observed. This could be due to a limitation of the Richards model in that it neglects the gas phase behaviour and other double porosity heterogeneous effects. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Anomalous photon-gauge boson coupling contribution to the exclusive vector boson pair production from two photon exchange in pp collisions at 13 TeV

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Martins, D. E.; Vilela Pereira, A.; Sá Borges, J.

    We study the W and Z pair production from two-photon exchange in proton-proton collisions at the LHC in order to evaluate the contributions of anomalous photon-gauge boson couplings, that simulates new particles and couplings predicted in many Standard Model (SM) extensions. The experimental results of W{sup +} W{sup −} exclusive production (pp → pW{sup +}W{sup −} p) at 7 TeV from the CMS collaboration [1] updates the experimental limits on anomalous couplings obtained at the Large Electron-Positron Collider (LEP). This motivates our present analysis hopefully anticipating the expected results using the Precision Proton Spectrometer (PPS) to be installed as partmore » of CMS. In this work, we consider the W{sup +}W{sup −} exclusive production to present the p{sub T} distribution of the lepton pair corresponding to the SM signal with p{sub T} (e, μ) > 10 GeV. Next, we consider the photon-gauge boson anomalous couplings by calculating, from the FPMC and MadGraph event generators, the process γγ → W{sup +}W{sup −} from a model with gauge boson quartic couplings, by considering a 1 TeV scale for new physical effects. We present our results for an integrated luminosity of 5 fb{sup −1} at center-of-mass energy of 7 TeV and for an integrated luminosity of 100 fb{sup −1} at 13 TeV. We present our preliminary results for Z pair exclusive production from two-photon exchange with anomalous couplings, where the ZZγγ quartic coupling is absent in the SM. We calculate the total cross section for the exclusive process and present the four lepton invariant mass distribution. Finally we present an outlook for the present analysis.« less

  2. On the quantum mechanics of consciousness, with application to anomalous phenomena

    NASA Astrophysics Data System (ADS)

    Jahn, Robert G.; Dunne, Brenda J.

    1986-08-01

    Theoretical explication of a growing body of empirical data on consciousness-related anomalous phenomena is unlikely to be achieved in terms of known physical processes. Rather, it will first be necessary to formulate the basic role of consciousness in the definition of reality before such anomalous experience can adequately be represented. This paper takes the position that reality is constituted only in the interaction of consciousness with its environment, and therefore that any scheme of conceptual organization developed to represent that reality must reflect the processes of consciousness as well as those of its environment. In this spirit, the concepts and formalisms of elementary quantum mechanics, as originally proposed to explain anomalous atomic-scale physical phenomena, are appropriated via metaphor to represent the general characteristics of consciousness interacting with any environment. More specifically, if consciousness is represented by a quantum mechanical wave function, and its environment by an appropriate potential profile, Schrödinger wave mechanics defines eigenfunctions and eigenvalues that can be associated with the cognitive and emotional experiences of that consciousness in that environment. To articulate this metaphor it is necessary to associate certain aspects of the formalism, such as the coordinate system, the quantum numbers, and even the metric itself, with various impressionistic descriptors of consciousness, such as its intensity, perspective, approach/avoidance attitude, balance between cognitive and emotional activity, and receptive/assertive disposition. With these established, a number of the generic features of quantum mechanics, such as the wave/particle duality, and the uncertainty, indistinguishability, and exclusion principles, display metaphoric relevance to familiar individual and collective experiences. Similarly, such traditional quantum theoretic exercises as the central force field and atomic structure, covalent molecular bonds, barrier penetration, and quantum statistical collective behavior become useful analogies for representation of a variety of consciousness experiences, both normal and anomalous, and for the design of experiments to study these systematically.

  3. ENSO modulation of seasonal rainfall and extremes in Indonesia

    NASA Astrophysics Data System (ADS)

    Supari; Tangang, Fredolin; Salimun, Ester; Aldrian, Edvin; Sopaheluwakan, Ardhasena; Juneng, Liew

    2017-12-01

    This paper provides a detailed description of how ENSO events affect seasonal and extreme precipitation over Indonesia. Daily precipitation data from 97 stations across Indonesia covering the period from 1981 to 2012 were used to investigate the effects of El Niño and La Niña on extreme precipitation characteristics including intensity, frequency and duration, as defined based on a subset of the Expert Team on Climate Change Detection and Indices (ETCCDI). Although anomalous signals in these three indices were consistent with those of total rainfall, anomalies in the duration of extremes [i.e., consecutive dry days (CDD) and consecutive wet days (CWD)] were much more robust. El Niño impacts were particularly prominent during June-July-August (JJA) and September-October-November (SON), when anomalously dry conditions were experienced throughout the country. However, from SON, a wet anomaly appeared over northern Sumatra, later expanding eastward during December-January-February (DJF) and March-April-May (MAM), creating contrasting conditions of wet in the west and dry in the east. We attribute this apparent eastward expansion of a wet anomaly during El Niño progression to the equatorial convergence of two anti-cyclonic circulations, one residing north of the equator and the other south of the equator. These anti-cyclonic circulations strengthen and weaken according to seasonal changes and their coupling with regional seas, hence shaping moisture transport and convergence. During La Niña events, the eastward expansion of an opposite (i.e., dry) anomaly was also present but less prominent than that of El Niño. We attribute this to differences in regional ocean—atmosphere coupling, which result in the contrasting seasonal evolution of the two corresponding anomalous cyclonic circulations and in turn suggests the strong nonlinearity of El Niño and La Niña responses over the Maritime Continent. Based on the seasonal behaviour of anomalous CDD and CWD, we propose five sub-divisions of the Indonesian region for both El Niño and La Niña.

  4. Optimize Short Term load Forcasting Anomalous Based Feed Forward Backpropagation

    NASA Astrophysics Data System (ADS)

    Mulyadi, Y.; Abdullah, A. G.; Rohmah, K. A.

    2017-03-01

    This paper contains the Short-Term Load Forecasting (STLF) using artificial neural network especially feed forward back propagation algorithm which is particularly optimized in order to getting a reduced error value result. Electrical load forecasting target is a holiday that hasn’t identical pattern and different from weekday’s pattern, in other words the pattern of holiday load is an anomalous. Under these conditions, the level of forecasting accuracy will be decrease. Hence we need a method that capable to reducing error value in anomalous load forecasting. Learning process of algorithm is supervised or controlled, then some parameters are arranged before performing computation process. Momentum constant a value is set at 0.8 which serve as a reference because it has the greatest converge tendency. Learning rate selection is made up to 2 decimal digits. In addition, hidden layer and input component are tested in several variation of number also. The test result leads to the conclusion that the number of hidden layer impact on the forecasting accuracy and test duration determined by the number of iterations when performing input data until it reaches the maximum of a parameter value.

  5. Crossover to the anomalous quantum regime in the extrinsic spin Hall effect of graphene

    NASA Astrophysics Data System (ADS)

    Ferreira, Aires; Milletari, Mirco

    Recent reports of spin-orbit coupling enhancement in chemically modified graphene have opened doors to studies of the spin Hall effect with massless chiral fermions. Here, we theoretically investigate the interaction and impurity density dependence of the extrinsic spin Hall effect in spin-orbit coupled graphene. We present a nonperturbative quantum diagrammatic calculation of the spin Hall response function in the strong-coupling regime that incorporates skew scattering and anomalous impurity density-independent contributions on equal footing. The spin Hall conductivity dependence on Fermi energy and electron-impurity interaction strength reveals the existence of experimentally accessible regions where anomalous quantum processes dominate. Our findings suggest that spin-orbit-coupled graphene is an ideal model system for probing the competition between semiclassical and bona fide quantum scattering mechanisms underlying the spin Hall effect. A.F. gratefully acknowledges the financial support of the Royal Society (U.K.).

  6. Mechanisms underlying anomalous diffusion in the plasma membrane.

    PubMed

    Krapf, Diego

    2015-01-01

    The plasma membrane is a complex fluid where lipids and proteins undergo diffusive motion critical to biochemical reactions. Through quantitative imaging analyses such as single-particle tracking, it is observed that diffusion in the cell membrane is usually anomalous in the sense that the mean squared displacement is not linear with time. This chapter describes the different models that are employed to describe anomalous diffusion, paying special attention to the experimental evidence that supports these models in the plasma membrane. We review models based on anticorrelated displacements, such as fractional Brownian motion and obstructed diffusion, and nonstationary models such as continuous time random walks. We also emphasize evidence for the formation of distinct compartments that transiently form on the cell surface. Finally, we overview heterogeneous diffusion processes in the plasma membrane, which have recently attracted considerable interest. Copyright © 2015. Published by Elsevier Inc.

  7. RISMA: A Rule-based Interval State Machine Algorithm for Alerts Generation, Performance Analysis and Monitoring Real-Time Data Processing

    NASA Astrophysics Data System (ADS)

    Laban, Shaban; El-Desouky, Aly

    2013-04-01

    The monitoring of real-time systems is a challenging and complicated process. So, there is a continuous need to improve the monitoring process through the use of new intelligent techniques and algorithms for detecting exceptions, anomalous behaviours and generating the necessary alerts during the workflow monitoring of such systems. The interval-based or period-based theorems have been discussed, analysed, and used by many researches in Artificial Intelligence (AI), philosophy, and linguistics. As explained by Allen, there are 13 relations between any two intervals. Also, there have also been many studies of interval-based temporal reasoning and logics over the past decades. Interval-based theorems can be used for monitoring real-time interval-based data processing. However, increasing the number of processed intervals makes the implementation of such theorems a complex and time consuming process as the relationships between such intervals are increasing exponentially. To overcome the previous problem, this paper presents a Rule-based Interval State Machine Algorithm (RISMA) for processing, monitoring, and analysing the behaviour of interval-based data, received from real-time sensors. The proposed intelligent algorithm uses the Interval State Machine (ISM) approach to model any number of interval-based data into well-defined states as well as inferring them. An interval-based state transition model and methodology are presented to identify the relationships between the different states of the proposed algorithm. By using such model, the unlimited number of relationships between similar large numbers of intervals can be reduced to only 18 direct relationships using the proposed well-defined states. For testing the proposed algorithm, necessary inference rules and code have been designed and applied to the continuous data received in near real-time from the stations of International Monitoring System (IMS) by the International Data Centre (IDC) of the Preparatory Commission for the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO). The CLIPS expert system shell has been used as the main rule engine for implementing the algorithm rules. Python programming language and the module "PyCLIPS" are used for building the necessary code for algorithm implementation. More than 1.7 million intervals constitute the Concise List of Frames (CLF) from 20 different seismic stations have been used for evaluating the proposed algorithm and evaluating stations behaviour and performance. The initial results showed that proposed algorithm can help in better understanding of the operation and performance of those stations. Different important information, such as alerts and some station performance parameters, can be derived from the proposed algorithm. For IMS interval-based data and at any period of time it is possible to analyze station behavior, determine the missing data, generate necessary alerts, and to measure some of station performance attributes. The details of the proposed algorithm, methodology, implementation, experimental results, advantages, and limitations of this research are presented. Finally, future directions and recommendations are discussed.

  8. Inelastic response of silicon to shock compression.

    PubMed

    Higginbotham, A; Stubley, P G; Comley, A J; Eggert, J H; Foster, J M; Kalantar, D H; McGonegle, D; Patel, S; Peacock, L J; Rothman, S D; Smith, R F; Suggit, M J; Wark, J S

    2016-04-13

    The elastic and inelastic response of [001] oriented silicon to laser compression has been a topic of considerable discussion for well over a decade, yet there has been little progress in understanding the basic behaviour of this apparently simple material. We present experimental x-ray diffraction data showing complex elastic strain profiles in laser compressed samples on nanosecond timescales. We also present molecular dynamics and elasticity code modelling which suggests that a pressure induced phase transition is the cause of the previously reported 'anomalous' elastic waves. Moreover, this interpretation allows for measurement of the kinetic timescales for transition. This model is also discussed in the wider context of reported deformation of silicon to rapid compression in the literature.

  9. Different structural morphologies of the two surfaces in some Co-based amorphous ribbons

    NASA Astrophysics Data System (ADS)

    Bordin, G.; Buttino, G.

    1992-12-01

    In nearly zero magnetostriction Co-based Metglas amorphous ribbons, the anomalous Hall effect is used to investigate the behaviour of the surfaces (dull or shiny). The electronic transport properties of a double-layer film, where one of the two layers examined is ferromagnetic and amorphous, and the other is a non-magnetic film, are interpreted on the basis of the mean free path method of Bergmann and Fuchs-Sondheimer theory. The results obtained confirm the different structural morphology of the amorphous surfaces (dull or shiny) already observed by means of bending effects on the initial permeability that depends on the way of winding the ribbons in toroidal samples of the same amorphous materials.

  10. Can I solve my structure by SAD phasing? Anomalous signal in SAD phasing

    DOE PAGES

    Terwilliger, Thomas C.; Bunkóczi, Gábor; Hung, Li-Wei; ...

    2016-03-01

    A key challenge in the SAD phasing method is solving a structure when the anomalous signal-to-noise ratio is low. We present a simple theoretical framework for describing measurements of anomalous differences and the resulting useful anomalous correlation and anomalous signal in a SAD experiment. Here, the useful anomalous correlation is defined as the correlation of anomalous differences with ideal anomalous differences from the anomalous substructure. The useful anomalous correlation reflects the accuracy of the data and the absence of minor sites. The useful anomalous correlation also reflects the information available for estimating crystallographic phases once the substructure has been determined.more » In contrast, the anomalous signal (the peak height in a model-phased anomalous difference Fourier at the coordinates of atoms in the anomalous substructure) reflects the information available about each site in the substructure and is related to the ability to find the substructure. A theoretical analysis shows that the expected value of the anomalous signal is the product of the useful anomalous correlation, the square root of the ratio of the number of unique reflections in the data set to the number of sites in the substructure, and a function that decreases with increasing values of the atomic displacement factor for the atoms in the substructure. In conclusion, this means that the ability to find the substructure in a SAD experiment is increased by high data quality and by a high ratio of reflections to sites in the substructure, and is decreased by high atomic displacement factors for the substructure.« less

  11. Can I solve my structure by SAD phasing? Anomalous signal in SAD phasing.

    PubMed

    Terwilliger, Thomas C; Bunkóczi, Gábor; Hung, Li Wei; Zwart, Peter H; Smith, Janet L; Akey, David L; Adams, Paul D

    2016-03-01

    A key challenge in the SAD phasing method is solving a structure when the anomalous signal-to-noise ratio is low. A simple theoretical framework for describing measurements of anomalous differences and the resulting useful anomalous correlation and anomalous signal in a SAD experiment is presented. Here, the useful anomalous correlation is defined as the correlation of anomalous differences with ideal anomalous differences from the anomalous substructure. The useful anomalous correlation reflects the accuracy of the data and the absence of minor sites. The useful anomalous correlation also reflects the information available for estimating crystallographic phases once the substructure has been determined. In contrast, the anomalous signal (the peak height in a model-phased anomalous difference Fourier at the coordinates of atoms in the anomalous substructure) reflects the information available about each site in the substructure and is related to the ability to find the substructure. A theoretical analysis shows that the expected value of the anomalous signal is the product of the useful anomalous correlation, the square root of the ratio of the number of unique reflections in the data set to the number of sites in the substructure, and a function that decreases with increasing values of the atomic displacement factor for the atoms in the substructure. This means that the ability to find the substructure in a SAD experiment is increased by high data quality and by a high ratio of reflections to sites in the substructure, and is decreased by high atomic displacement factors for the substructure.

  12. Anomalous versus slowed-down Brownian diffusion in the ligand-binding equilibrium.

    PubMed

    Soula, Hédi; Caré, Bertrand; Beslon, Guillaume; Berry, Hugues

    2013-11-05

    Measurements of protein motion in living cells and membranes consistently report transient anomalous diffusion (subdiffusion) that converges back to a Brownian motion with reduced diffusion coefficient at long times after the anomalous diffusion regime. Therefore, slowed-down Brownian motion could be considered the macroscopic limit of transient anomalous diffusion. On the other hand, membranes are also heterogeneous media in which Brownian motion may be locally slowed down due to variations in lipid composition. Here, we investigate whether both situations lead to a similar behavior for the reversible ligand-binding reaction in two dimensions. We compare the (long-time) equilibrium properties obtained with transient anomalous diffusion due to obstacle hindrance or power-law-distributed residence times (continuous-time random walks) to those obtained with space-dependent slowed-down Brownian motion. Using theoretical arguments and Monte Carlo simulations, we show that these three scenarios have distinctive effects on the apparent affinity of the reaction. Whereas continuous-time random walks decrease the apparent affinity of the reaction, locally slowed-down Brownian motion and local hindrance by obstacles both improve it. However, only in the case of slowed-down Brownian motion is the affinity maximal when the slowdown is restricted to a subregion of the available space. Hence, even at long times (equilibrium), these processes are different and exhibit irreconcilable behaviors when the area fraction of reduced mobility changes. Copyright © 2013 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  13. The role of H-bond in the high-pressure chemistry of model molecules

    NASA Astrophysics Data System (ADS)

    Fanetti, Samuele; Citroni, Margherita; Dziubek, Kamil; Medre Nobrega, Marcelo; Bini, Roberto

    2018-03-01

    Pressure is an extraordinary tool to modify direction and strength of intermolecular interactions with important consequences on the chemical stability of molecular materials. The decrease of the distance among nearest neighbour molecules can give rise to reactive configurations reflecting the crystal arrangement and leading to association processes. In this context, the role of the H-bonds is very peculiar because their usual strengthening with rising pressure does not necessarily configure a decrease of the reaction activation energy but, on the contrary, can give rise to an anomalous stability of the system. In spite of this central role, the mechanisms by which a chemical reaction is favoured or prevented by H-bonding under high pressure conditions is a poorly explored field. Here we review a few studies where the chemical behaviour of simple molecular systems under static compression was related to the H-bonding evolution with pressure. These results are able to clarify a wealth of changes of the chemical and physical properties caused by the strengthening with pressure of the H-bonding network and provide additional tools to understand the mechanisms of high-pressure reactivity, a mandatory step to make these synthetic methods of potential interest for applicative purposes.

  14. The Anomalous Process γπ → ππ and its Impact on the π0 Transition Form Factor

    NASA Astrophysics Data System (ADS)

    Kubis, Bastian

    2014-12-01

    The process γπ → ππ, in the limit of vanishing photon and pion energies, is determined by the chiral anomaly. This reaction can be investigated experimentally using Primakoff reactions, as currently done at COMPASS. We derive a dispersive representation that allows one to extract the chiral anomaly from cross-section measurements up to 1 GeV, where effects of the ρ resonance are included model-independently via the ππ P-wave phase shift. We discuss how this amplitude serves as an important input to a dispersion-theoretical analysis of the π0 transition form factor, which in turn is a vital ingredient to the hadronic light-by-light contribution to the anomalous magnetic moment of the muon.

  15. Fractional cable model for signal conduction in spiny neuronal dendrites

    NASA Astrophysics Data System (ADS)

    Vitali, Silvia; Mainardi, Francesco

    2017-06-01

    The cable model is widely used in several fields of science to describe the propagation of signals. A relevant medical and biological example is the anomalous subdiffusion in spiny neuronal dendrites observed in several studies of the last decade. Anomalous subdiffusion can be modelled in several ways introducing some fractional component into the classical cable model. The Chauchy problem associated to these kind of models has been investigated by many authors, but up to our knowledge an explicit solution for the signalling problem has not yet been published. Here we propose how this solution can be derived applying the generalized convolution theorem (known as Efros theorem) for Laplace transforms. The fractional cable model considered in this paper is defined by replacing the first order time derivative with a fractional derivative of order α ∈ (0, 1) of Caputo type. The signalling problem is solved for any input function applied to the accessible end of a semi-infinite cable, which satisfies the requirements of the Efros theorem. The solutions corresponding to the simple cases of impulsive and step inputs are explicitly calculated in integral form containing Wright functions. Thanks to the variability of the parameter α, the corresponding solutions are expected to adapt to the qualitative behaviour of the membrane potential observed in experiments better than in the standard case α = 1.

  16. Anomalous phosphine sensitivity coefficients as probes for a possible variation of the proton-to-electron mass ratio

    NASA Astrophysics Data System (ADS)

    Owens, A.; Yurchenko, S. N.; Špirko, V.

    2018-02-01

    A robust variational approach is used to investigate the sensitivity of the rotation-vibration spectrum of phosphine (PH3) to a possible cosmological variation of the proton-to-electron mass ratio, μ. Whilst the majority of computed sensitivity coefficients, T, involving the low-lying vibrational states acquire the expected values of T ≈ -1 and T ≈ -1/2 for rotational and ro-vibrational transitions, respectively, anomalous sensitivities are uncovered for the A1 - A2 splittings in the ν2/ν4, ν1/ν3 and 2ν _4^{ℓ=0}/2ν _4^{ℓ=2} manifolds of PH3. A pronounced Coriolis interaction between these states in conjunction with accidentally degenerate A1 and A2 energy levels produces a series of enhanced sensitivity coefficients. Phosphine is expected to occur in a number of different astrophysical environments and has potential for investigating a drifting constant. Furthermore, the displayed behaviour hints at a wider trend in molecules of C_{3v}(M) symmetry, thus demonstrating that the splittings induced by higher-order ro-vibrational interactions are well suited for probing μ in other symmetric top molecules in space, since these low-frequency transitions can be straightforwardly detected by radio telescopes.

  17. Anomalous magnetoelastic behaviour near morphotropic phase boundary in ferromagnetic Tb 1-xNd xCo 2 system

    DOE PAGES

    Murtaza, Adil; Yang, Sen; Zhou, Chao; ...

    2016-08-04

    In this study, we report a morphotropic phase boundary (MPB) involved ferromagnetic system Tb 1-xNd xCo 2 and reveal the corresponding structural and magnetoelastic properties of this system. With high resolution synchrotron X-ray diffractometry, the crystal structure of the TbCo 2-rich side is detected to be rhombohedral and that of NdCo 2-rich side is tetragonal below their respective Curie temperatures TC. The MPB composition Tb 0.35Nd 0.65Co 2 corresponds to the coexistence of the rhombohedral phase (R-phase) and tetragonal phase ( T-phase). Contrary to previously reported MPB involved ferromagnetic systems, the MPB composition of Tb 0.35Nd 0.65Co 2 shows minimummore » magnetization which can be understood as compensation of sublattice moments between the R-phase and the T-phase. Furthermore, magnetostriction of Tb 1-xNd xCo 2 decreases with increasing Nd concentration until x = 0.8 and then increases in the negative direction with further increasing Nd concentration; the optimum point for magnetoelastic properties lies towards the rhombohedral phase. Finally, our work not only shows an anomalous type of ferromagnetic MPB but also provides an effective way to design functional materials.« less

  18. Anomalous diffusion due to the non-Markovian process of the dust particle velocity in complex plasmas

    NASA Astrophysics Data System (ADS)

    Ghannad, Z.; Hakimi Pajouh, H.

    2017-12-01

    In this work, the motion of a dust particle under the influence of the random force due to dust charge fluctuations is considered as a non-Markovian stochastic process. Memory effects in the velocity process of the dust particle are studied. A model is developed based on the fractional Langevin equation for the motion of the dust grain. The fluctuation-dissipation theorem for the dust grain is derived from this equation. The mean-square displacement and the velocity autocorrelation function of the dust particle are obtained in terms of the Mittag-Leffler functions. Their asymptotic behavior and the dust particle temperature due to charge fluctuations are studied in the long-time limit. As an interesting result, it is found that the presence of memory effects in the velocity process of the dust particle as a non-Markovian process can cause an anomalous diffusion in dusty plasmas. In this case, the velocity autocorrelation function of the dust particle has a power-law decay like t - α - 2, where the exponent α take values 0 < α < 1.

  19. Magnetic anomalies in Fe-doped NiO nanoparticle

    NASA Astrophysics Data System (ADS)

    Pradeep, R.; Gandhi, A. C.; Tejabhiram, Y.; Mathar Sahib, I. K. Md; Shimura, Y.; Karmakar, L.; Das, D.; Wu, Sheng Yun; Hayakawa, Y.

    2017-09-01

    Undoped and iron-doped NiO nanoparticle were synthesized by standard hydrothermal method. A detailed study is carried out on the effect of dopant concentration on morphology, structural, resonance and magnetic properties of NiO nanoparticle by varying the Fe concentration from 0.01 to 0.10 M. The synchrotron-x-ray diffraction confirmed that no secondary phase was observed other than NiO. The x-ray photoelectron spectroscopy studies revealed that, Fe was primarily in the trivalent state, replacing the Ni2+ ion inside the octahedral crystal site of NiO. The Electron paramagnetic studies revealed the ferromagnetic cluster formation at high doping concentration (5 and 10%). The ZFC-FC curves displayed an average blocking temperature around 180 K due to particle size distribution. The anomalous behaviour of spontaneous exchange bias (H SEB) and magnetic remanence (M r) for all Fe-doped samples observed at 5 K showed an increase (0.1316-0.1384 emu g-1) in the moment of frozen spin (M p) as the dopant concentration increased. The role of frozen spin moment in spontaneous exchange bias behaviour was discussed.

  20. Anomalous diffusion of Ibuprofen in cyclodextrin nanosponge hydrogels: an HRMAS NMR study.

    PubMed

    Ferro, Monica; Castiglione, Franca; Punta, Carlo; Melone, Lucio; Panzeri, Walter; Rossi, Barbara; Trotta, Francesco; Mele, Andrea

    2014-01-01

    Ibuprofen sodium salt (IP) was encapsulated in cyclodextrin nanosponges (CDNS) obtained by cross-linking of β-cyclodextrin with ethylenediaminetetraacetic acid dianhydride (EDTAn) in two different preparations: CDNSEDTA 1:4 and 1:8, where the 1:n notation indicates the CD to EDTAn molar ratio. The entrapment of IP was achieved by swelling the two polymers with a 0.27 M solution of IP in D2O, leading to colourless, homogeneous hydrogels loaded with IP. The molecular environment and the transport properties of IP in the hydrogels were studied by high resolution magic angle spinning (HRMAS) NMR spectroscopy. The mean square displacement (MSD) of IP in the gels was obtained by a pulsed field gradient spin echo (PGSE) NMR pulse sequence at different observation times t d. The MSD is proportional to the observation time elevated to a scaling factor α. The α values define the normal Gaussian random motion (α = 1), or the anomalous diffusion (α < 1, subdiffusion, α > 1 superdiffusion). The experimental data here reported point out that IP undergoes subdiffusive regime in CDNSEDTA 1:4, while a slightly superdiffusive behaviour is observed in CDNSEDTA 1:8. The transition between the two dynamic regimes is triggered by the polymer structure. CDNSEDTA 1:4 is characterized by a nanoporous structure able to induce confinement effects on IP, thus causing subdiffusive random motion. CDNSEDTA 1:8 is characterized not only by nanopores, but also by dangling EDTA groups ending with ionized COO(-) groups. The negative potential provided by such groups to the polymer backbone is responsible for the acceleration effects on the IP anion thus leading to the superdiffusive behaviour observed. These results point out that HRMAS NMR spectroscopy is a powerful direct method for the assessment of the transport properties of a drug encapsulated in polymeric scaffolds. The diffusion properties of IP in CDNS can be modulated by suitable polymer synthesis; this finding opens the possibility to design suitable systems for drug delivery with predictable and desired drug release properties.

  1. On the dynamics of interaction between a moving mass and an infinite one-dimensional elastic structure at the stability limit

    NASA Astrophysics Data System (ADS)

    Mazilu, Traian; Dumitriu, Mădălina; Tudorache, Cristina

    2011-07-01

    The paper herein deals with the study of the dynamic behaviour generated by the instability of the vibration of a loaded mass, uniformly moving along an Euler-Bernoulli beam on a viscoelastic foundation, induced by the anomalous Doppler waves excited in the beam. This issue is relevant for the case of modern trains travelling along a track with soft soil when the trains speed exceeds the phase velocity of the waves induced in the track. The model corresponds to a railway vehicle reduced to a loaded wheel running along a (half) track. The beam takes account of the bending stiffness of the rail and the mass of the track, including the mass of the rail, semi-sleepers and half of the ballast layer, where the viscoelastic foundation represents the subgrade. The model includes the wheel/rail Hertzian contact and it allows the simulation of the possibility of contact loss. The nonlinear equations of motion are integrated using a numerical approach based on the Green's function method. When the vibration becomes unstable, the system evolution is a limit cycle characterised by a succession of shocks, due to the action of two opposite factors: the anomalous Doppler waves that pump energy at the interface between the moving mass and the beam, thus forcing the mass to take off, and the static load that push the mass downwards. The frequency of the shocks increases at higher velocity and the magnitude of the impact force decreases; the most dangerous velocity is the critical one, which represents the stability limit of the linear approximation of the motion equations. The transient behaviour that precedes the limit cycle appearance is being analysed. The Hertzian contact influences the time history of the limit cycle and the magnitude of the impact force and, therefore, it is essential to be included in the model. To the authors' knowledge, this problem has never been dealt with.

  2. Event-Related Potentials Reveal Anomalous Morphosyntactic Processing in Developmental Dyslexia

    ERIC Educational Resources Information Center

    Cantiani, Chiara; Lorusso, Maria Luisa; Perego, Paolo; Molteni, Massimo; Guasti, Maria Teresa

    2013-01-01

    In the light of the literature describing oral language difficulties in developmental dyslexia (DD), event-related potentials were used in order to compare morphosyntactic processing in 16 adults with DD (aged 20-28 years) and unimpaired controls. Sentences including subject-verb agreement violations were presented auditorily, with grammaticality…

  3. The Role of Semantics in Sentence-Processing.

    ERIC Educational Resources Information Center

    Dell, Gary S.

    In order to explore the effect of semantic organization on the comprehension of sentences, this research, based on the hypothesis that fully grammatical sentences would be processed more easily than anomalous sentences, depended on data provided by 20 paid college students serving in individual sessions. Each student listened to 30 tape-recorded…

  4. Can I solve my structure by SAD phasing? Planning an experiment, scaling data and evaluating the useful anomalous correlation and anomalous signal.

    PubMed

    Terwilliger, Thomas C; Bunkóczi, Gábor; Hung, Li Wei; Zwart, Peter H; Smith, Janet L; Akey, David L; Adams, Paul D

    2016-03-01

    A key challenge in the SAD phasing method is solving a structure when the anomalous signal-to-noise ratio is low. Here, algorithms and tools for evaluating and optimizing the useful anomalous correlation and the anomalous signal in a SAD experiment are described. A simple theoretical framework [Terwilliger et al. (2016), Acta Cryst. D72, 346-358] is used to develop methods for planning a SAD experiment, scaling SAD data sets and estimating the useful anomalous correlation and anomalous signal in a SAD data set. The phenix.plan_sad_experiment tool uses a database of solved and unsolved SAD data sets and the expected characteristics of a SAD data set to estimate the probability that the anomalous substructure will be found in the SAD experiment and the expected map quality that would be obtained if the substructure were found. The phenix.scale_and_merge tool scales unmerged SAD data from one or more crystals using local scaling and optimizes the anomalous signal by identifying the systematic differences among data sets, and the phenix.anomalous_signal tool estimates the useful anomalous correlation and anomalous signal after collecting SAD data and estimates the probability that the data set can be solved and the likely figure of merit of phasing.

  5. Can I solve my structure by SAD phasing? Planning an experiment, scaling data and evaluating the useful anomalous correlation and anomalous signal

    DOE PAGES

    Terwilliger, Thomas C.; Bunkóczi, Gábor; Hung, Li-Wei; ...

    2016-03-01

    A key challenge in the SAD phasing method is solving a structure when the anomalous signal-to-noise ratio is low. Here, we describe algorithms and tools for evaluating and optimizing the useful anomalous correlation and the anomalous signal in a SAD experiment. A simple theoretical framework [Terwilliger et al.(2016),Acta Cryst.D72, 346–358] is used to develop methods for planning a SAD experiment, scaling SAD data sets and estimating the useful anomalous correlation and anomalous signal in a SAD data set. Thephenix.plan_sad_experimenttool uses a database of solved and unsolved SAD data sets and the expected characteristics of a SAD data set to estimatemore » the probability that the anomalous substructure will be found in the SAD experiment and the expected map quality that would be obtained if the substructure were found. Thephenix.scale_and_mergetool scales unmerged SAD data from one or more crystals using local scaling and optimizes the anomalous signal by identifying the systematic differences among data sets, and thephenix.anomalous_signaltool estimates the useful anomalous correlation and anomalous signal after collecting SAD data and estimates the probability that the data set can be solved and the likely figure of merit of phasing.« less

  6. Can I solve my structure by SAD phasing? Planning an experiment, scaling data and evaluating the useful anomalous correlation and anomalous signal

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Terwilliger, Thomas C.; Bunkóczi, Gábor; Hung, Li-Wei

    A key challenge in the SAD phasing method is solving a structure when the anomalous signal-to-noise ratio is low. Here, we describe algorithms and tools for evaluating and optimizing the useful anomalous correlation and the anomalous signal in a SAD experiment. A simple theoretical framework [Terwilliger et al.(2016),Acta Cryst.D72, 346–358] is used to develop methods for planning a SAD experiment, scaling SAD data sets and estimating the useful anomalous correlation and anomalous signal in a SAD data set. Thephenix.plan_sad_experimenttool uses a database of solved and unsolved SAD data sets and the expected characteristics of a SAD data set to estimatemore » the probability that the anomalous substructure will be found in the SAD experiment and the expected map quality that would be obtained if the substructure were found. Thephenix.scale_and_mergetool scales unmerged SAD data from one or more crystals using local scaling and optimizes the anomalous signal by identifying the systematic differences among data sets, and thephenix.anomalous_signaltool estimates the useful anomalous correlation and anomalous signal after collecting SAD data and estimates the probability that the data set can be solved and the likely figure of merit of phasing.« less

  7. Principles of Positive Behaviour Supports: Using the FBA as a Problem-Solving Approach to Address Challenging Behaviours beyond Special Populations

    ERIC Educational Resources Information Center

    Moreno, Gerardo; Bullock, Lyndal M.

    2011-01-01

    The Functional Behavioural Assessment (FBA) is an investigative process that examines the context of challenging behaviours in the classroom. Information gleaned from the FBA process is used to develop a behaviour intervention plan to address the challenging behaviour and teach a socially acceptable replacement behaviour. However, the FBA has…

  8. Impact of Stress on Anomalous Transport in Fractured Rock

    NASA Astrophysics Data System (ADS)

    Kang, P. K.; Lei, Q.; Lee, S.; Dentz, M.; Juanes, R.

    2016-12-01

    Fluid flow and transport in fractured rock controls many natural and engineered processes in the subsurface. However, characterizing flow and transport through fractured media is challenging due to the large heterogeneity of fractured rock properties. In addition to these "static" challenges, geologic fractures are always under significant overburden stress, and changes in the stress state can lead to changes in the fracture's ability to conduct fluids. While confining stress has been shown to impact fluid flow through fractures in a fundamental way, the impact of confining stress on transport through fractured rock remains largely unexplored. The link between anomalous (non-Fickian) transport and confining stress has been shown only recently, at the level of a single rough fracture [1]. Here, we investigate the impact of confining stress on flow and transport through discrete fracture networks. We model geomechanical effects in 2D fractured rock by means of a finite-discrete element method (FEMDEM), which can capture the deformation of matrix blocks, reactivation and propagation of cracks. We implement a joint constitutive model within the FEMDEM framework to simulate the effect of fracture roughness. We apply the model to a fracture network extracted from the geological map of an actual outcrop to obtain the aperture field at different stress conditions (Figure 1). We then simulate fluid flow and particle transport through the stressed fracture networks. We observe that anomalous transport emerges in response to confining stress on the fracture networks, and show that this anomalous behavior can be linked to the stress state of the rock. Finally, we develop an effective transport model that captures the anomalous transport through stressed fractures. Our results point to a heretofore unrecognized link between geomechanics and anomalous transport in discrete fractured networks. [1] P. K. Kang, S. Brown, and R. Juanes, Emergence of anomalous transport in stressed rough fractures. Earth and Planetary Science Letters, to appear (2016). Figure (a) Map of maximum principal stress with a vertical normal compressive stress of 3 MPa at top and bottom boundaries, and 1MPa at left and right boundaries. (b) Normal compressive stress of 15 MPa at top and bottom boundaries, and 5MPa at left and right boundaries.

  9. An index of anomalous convective instability to detect tornadic and hail storms

    NASA Astrophysics Data System (ADS)

    Qian, Weihong; Leung, Jeremy Cheuk-Hin; Luo, Weimeng; Du, Jun; Gao, Jidong

    2017-12-01

    In this article, the synoptic-scale spatial structures for raising tornadic and hail storms are compared by analyzing the total and anomalous variable fields from the troposphere to the stratosphere. 15 cases of tornado outbreaks and 20 cases of hail storms that occurred in the central United States during 1980-2011 were studied. The anomalous temperature-height field shows that a tornadic or hail storm usually occurs at the boundary of anomalous warm and cold air masses horizontally in the troposphere. In one side, an anomalous warm air mass in the mid-low troposphere and an anomalous cold air mass in the stratosphere are vertically separated by a positive center of height anomalies at the upper troposphere. In another side, an opposite vertical pattern shows that an anomalous cold air mass in the mid-low troposphere and an anomalous warm air mass in the stratosphere are separated by a negative center of height anomalies at the upper troposphere. Therefore, two pairs of adjacent anomalous warm/cold centers and one pair of anomalous high/low centers combining together form a major tornadic or hail storm paradigm, which can be physically considered as the storage of anomalous potential energy (APE) to generate severe weather. To quantitatively measure the APE, we define an index of anomalous convective instability (ACI) which is a difference of integrating temperature anomalies based on two vertically opposite anomalous air masses. The APE transformation to anomalous kinetic energy, which reduces horizontal and vertical gradients of temperature anomalies, produces anomalous rising and sinking flows in the lower-layer anomalous warm and cold air mass sides, respectively. The intensity of ACI index for tornadic storm cases is 1.5 times larger than that of hail storm cases in average. Thus, this expression of anomalous variables is better than total variables used in the traditional synoptic chart and the ACI index is better than other indices to detect potential tornadic and hail storms in order to understand the environmental conditions affecting severe weather in analytical and model output datasets.

  10. Anomalous dielectric relaxation with linear reaction dynamics in space-dependent force fields.

    PubMed

    Hong, Tao; Tang, Zhengming; Zhu, Huacheng

    2016-12-28

    The anomalous dielectric relaxation of disordered reaction with linear reaction dynamics is studied via the continuous time random walk model in the presence of space-dependent electric field. Two kinds of modified reaction-subdiffusion equations are derived for different linear reaction processes by the master equation, including the instantaneous annihilation reaction and the noninstantaneous annihilation reaction. If a constant proportion of walkers is added or removed instantaneously at the end of each step, there will be a modified reaction-subdiffusion equation with a fractional order temporal derivative operating on both the standard diffusion term and a linear reaction kinetics term. If the walkers are added or removed at a constant per capita rate during the waiting time between steps, there will be a standard linear reaction kinetics term but a fractional order temporal derivative operating on an anomalous diffusion term. The dielectric polarization is analyzed based on the Legendre polynomials and the dielectric properties of both reactions can be expressed by the effective rotational diffusion function and component concentration function, which is similar to the standard reaction-diffusion process. The results show that the effective permittivity can be used to describe the dielectric properties in these reactions if the chemical reaction time is much longer than the relaxation time.

  11. High Electrocatalytic Hydrogen Evolution Activity of an Anomalous Ruthenium Catalyst.

    PubMed

    Zheng, Yao; Jiao, Yan; Zhu, Yihan; Li, Lu Hua; Han, Yu; Chen, Ying; Jaroniec, Mietek; Qiao, Shi-Zhang

    2016-12-14

    Hydrogen evolution reaction (HER) is a critical process due to its fundamental role in electrocatalysis. Practically, the development of high-performance electrocatalysts for HER in alkaline media is of great importance for the conversion of renewable energy to hydrogen fuel via photoelectrochemical water splitting. However, both mechanistic exploration and materials development for HER under alkaline conditions are very limited. Precious Pt metal, which still serves as the state-of-the-art catalyst for HER, is unable to guarantee a sustainable hydrogen supply. Here we report an anomalously structured Ru catalyst that shows 2.5 times higher hydrogen generation rate than Pt and is among the most active HER electrocatalysts yet reported in alkaline solutions. The identification of new face-centered cubic crystallographic structure of Ru nanoparticles was investigated by high-resolution transmission electron microscopy imaging, and its formation mechanism was revealed by spectroscopic characterization and theoretical analysis. For the first time, it is found that the Ru nanocatalyst showed a pronounced effect of the crystal structure on the electrocatalytic activity tested under different conditions. The combination of electrochemical reaction rate measurements and density functional theory computation shows that the high activity of anomalous Ru catalyst in alkaline solution originates from its suitable adsorption energies to some key reaction intermediates and reaction kinetics in the HER process.

  12. Osmotic generation of 'anomalous' fluid pressures in geological environments

    USGS Publications Warehouse

    Neuzii, C.E.

    2000-01-01

    Osmotic pressures are generated by differences in chemical potential of a solution across a membrane. But whether osmosis can have a significant effect on the pressure of fluids in geological environments has been controversial, because the membrane properties of geological media are poorly understood. 'Anomalous' pressures - large departures from hydrostatic pressure that are not explicable in terms of topographic or fluid-density effects are widely found in geological settings, and are commonly considered to result from processes that alter the pore or fluid volume, which in turn implies crustal changes happening at a rate too slow to observe directly. Yet if osmosis can explain some anomalies, there is no need to invoke such dynamic geological processes in those cases. Here I report results of a nine- year in situ measurement of fluid pressures and solute concentrations in shale that are consistent with the generation of large (up to 20 MPa) osmotic-pressure anomalies which could persist for tens of millions of years. Osmotic pressures of this magnitude and duration can explain many of the pressure anomalies observed in geological settings. The require, however, small shale porosity and large contrasts in the amount of dissolved solids in the pore waters - criteria that may help to distinguish between osmotic and crystal-dynamic origins of anomalous pressures.

  13. Anomalous C-V response correlated to relaxation processes in TiO{sub 2} thin film based-metal-insulator-metal capacitor: Effect of titanium and oxygen defects

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kahouli, A., E-mail: kahouli.kader@yahoo.fr; University Grenoble Alpes, G2Elab, F-38000 Grenoble; Marichy, C.

    2015-04-21

    Capacitance-voltage (C–V) and capacitance-frequency (C–f) measurements are performed on atomic layer deposited TiO{sub 2} thin films with top and bottom Au and Pt electrodes, respectively, over a large temperature and frequency range. A sharp capacitance peak/discontinuity (C–V anomalous) is observed in the C–V characteristics at various temperatures and voltages. It is demonstrated that this phenomenon is directly associated with oxygen vacancies. The C–V peak irreversibility and dissymmetry at the reversal dc voltage are attributed to difference between the Schottky contacts at the metal/TiO{sub 2} interfaces. Dielectric analyses reveal two relaxation processes with degeneration of the activation energy. The low trapmore » level of 0.60–0.65 eV is associated with the first ionized oxygen vacancy at low temperature, while the deep trap level of 1.05 eV is associated to the second ionized oxygen vacancy at high temperature. The DC conductivity of the films exhibits a transition temperature at 200 °C, suggesting a transition from a conduction regime governed by ionized oxygen vacancies to one governed by interstitial Ti{sup 3+} ions. Both the C–V anomalous and relaxation processes in TiO{sub 2} arise from oxygen vacancies, while the conduction mechanism at high temperature is governed by interstitial titanium ions.« less

  14. Unusual solvatochromic absorbance probe behaviour within mixtures of poly(ethylene glycol)-400 + ionic liquid, [bmim][Tf2N

    NASA Astrophysics Data System (ADS)

    Ali, Anwar; Ali, Maroof; Malik, Nisar Ahmad; Uzair, Sahar

    2014-03-01

    The potentially green solvents made up of ionic liquids (ILs) and poly(ethylene glycols) may have wide range of the applications in many chemical and biochemical fields. In the present work, solvatochromic absorbance probe behaviour is used to assess the physicochemical properties of the mixtures composed of PEG-400 + IL, 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, [bmim][Tf2N]. Lowest energy intramolecular charge-transfer absorbance maxima of a betaine dye, i.e., ETN , indicates the dipolarity/polarizability and/or hydrogen-bond donating (HBD) acidity of the [bmim][Tf2N] + PEG-400 mixtures to be even higher than that of neat [bmim][Tf2N], the solution component with higher dipolarity/polarizability and/or HBD acidity. Dipolarity/polarizability (π∗) obtained separately from the electronic absorbance response of probe N,N-diethyl-4-nitroaniline, and the HBD acidity (α) of PEG-400 + [bmim][Tf2N] mixtures are also observed to be anomalously high. A comparative study of the PEG + IL mixtures has also been done with PEG-400 + molecular organic solvents (protic polar [methanol], aprotic polar [N,N-dimethylformamide], and non polar, [benzene]) mixtures, but these mixtures do not show this type of unusual behaviour. A four-parameter simplified combined nearly ideal binary solvent/Redlich-Kister (CNIBS/R-K) equation is shown to satisfactorily predict the solvatochromic parameters within PEG-400 + different solvent mixtures.

  15. Areas of Weakly Anomalous to Anomalous Surface Temperature in Alamosa and Saguache Counties, Colorado, as Identified from ASTER Thermal Data

    DOE Data Explorer

    Khalid Hussein

    2012-02-01

    This "Weakly Anomalous to Anomalous Surface Temperature" dataset differs from the "Anomalous Surface Temperature" dataset for this county (another remotely sensed CIRES product) by showing areas of modeled temperatures between 1o and 2o above the mean, as opposed to the greater than 2o temperatures contained in the "Anomalous Surface Temperature" dataset. Note: 'o' is used in this description to represent lowercase sigma

  16. Can I solve my structure by SAD phasing? Planning an experiment, scaling data and evaluating the useful anomalous correlation and anomalous signal

    PubMed Central

    Terwilliger, Thomas C.; Bunkóczi, Gábor; Hung, Li-Wei; Zwart, Peter H.; Smith, Janet L.; Akey, David L.; Adams, Paul D.

    2016-01-01

    A key challenge in the SAD phasing method is solving a structure when the anomalous signal-to-noise ratio is low. Here, algorithms and tools for evaluating and optimizing the useful anomalous correlation and the anomalous signal in a SAD experiment are described. A simple theoretical framework [Terwilliger et al. (2016 ▸), Acta Cryst. D72, 346–358] is used to develop methods for planning a SAD experiment, scaling SAD data sets and estimating the useful anomalous correlation and anomalous signal in a SAD data set. The phenix.plan_sad_experiment tool uses a database of solved and unsolved SAD data sets and the expected characteristics of a SAD data set to estimate the probability that the anomalous substructure will be found in the SAD experiment and the expected map quality that would be obtained if the substructure were found. The phenix.scale_and_merge tool scales unmerged SAD data from one or more crystals using local scaling and optimizes the anomalous signal by identifying the systematic differences among data sets, and the phenix.anomalous_signal tool estimates the useful anomalous correlation and anomalous signal after collecting SAD data and estimates the probability that the data set can be solved and the likely figure of merit of phasing. PMID:26960123

  17. Recovery Characteristics of Anomalous Stress-Induced Leakage Current of 5.6 nm Oxide Films

    NASA Astrophysics Data System (ADS)

    Inatsuka, Takuya; Kumagai, Yuki; Kuroda, Rihito; Teramoto, Akinobu; Sugawa, Shigetoshi; Ohmi, Tadahiro

    2012-04-01

    Anomalous stress-induced leakage current (SILC), which has a much larger current density than average SILC, causes severe bit error in flash memories. To suppress anomalous SILC, detailed evaluations are strongly required. We evaluate the characteristics of anomalous SILC of 5.6 nm oxide films using a fabricated array test pattern, and recovery characteristics are observed. Some characteristics of typical anomalous cells in the time domain are measured, and the recovery characteristics of average and anomalous SILCs are examined. Some of the anomalous cells have random telegraph signals (RTSs) of gate leakage current, which are characterized as discrete and random switching phenomena. The dependence of RTSs on the applied electric field is investigated, and the recovery tendency of anomalous SILC with and without RTSs are also discussed.

  18. Relationship between the anomalous diffusion and the fractal dimension of the environment

    NASA Astrophysics Data System (ADS)

    Zhokh, Alexey; Trypolskyi, Andrey; Strizhak, Peter

    2018-03-01

    In this letter, we provide an experimental study highlighting a relation between the anomalous diffusion and the fractal dimension of the environment using the methanol anomalous transport through the porous solid pellets with various pores geometries and different chemical compositions. The anomalous diffusion exponent was derived from the non-integer order of the time-fractional diffusion equation that describes the methanol anomalous transport through the solid media. The surface fractal dimension was estimated from the nitrogen adsorption isotherms using the Frenkel-Halsey-Hill method. Our study shows that decreasing the fractal dimension leads to increasing the anomalous diffusion exponent, whereas the anomalous diffusion constant is independent on the fractal dimension. We show that the obtained results are in a good agreement with the anomalous diffusion model on a fractal mesh.

  19. Anomalous Diffusion Reports on the Interaction of Misfolded Proteins with the Quality Control Machinery in the Endoplasmic Reticulum

    PubMed Central

    Malchus, Nina; Weiss, Matthias

    2010-01-01

    A multitude of transmembrane proteins enters the endoplasmic reticulum (ER) as unfolded polypeptide chains. During their folding process, they interact repetitively with the ER's quality control machinery. Here, we have used fluorescence correlation spectroscopy to probe these interactions for a prototypical transmembrane protein, VSVG ts045, in vivo. While both folded and unfolded VSVG ts045 showed anomalous diffusion, the unfolded protein had a significantly stronger anomaly. This difference subsided when unfolded VSVG ts045 was in a complex with its chaperone calnexin, or when a mutant form of VSVG ts045 with only one glycan was used. Our experimental data and accompanying simulations suggest that the folding sensor of the quality control (UGT1) oligomerizes unfolded VSVG ts045, leading to a more anomalous/obstructed diffusion. In contrast, calnexin dissolves the oligomers, rendering unfolded VSVG ts045 more mobile, and hence prevents poisoning of the ER. PMID:20713018

  20. Modulation of galactic and anomalous cosmic rays in the inner heliosphere

    NASA Astrophysics Data System (ADS)

    Heber, B.

    Our knowledge on how galactic and anomalous cosmic rays are modulated in the inner heliosphere has been dramatically enlarged due to measurements provided by several missions launched in the past ten years. The current paradigma of singly charged anomalous cosmic rays has been confirmed by recent measurements from the SAMPEX and ACE satelite. Ulysses explored the inner heliosphere at polar regions during the last solar minimum period and is heading again to high heliographic latitudes during the time of the conference in July, 2000. The Sun approaches maximum activity when the spacecraft is at high heliographic latitudes giving us for the first time the possibility to explore modulation of cosmic rays in the inner three-dimensional heliosphere during such conditions. Ulysses electron measurements in addition to the 1 AU ICE electron and IMP helium measurements allows us to investigate charge sign dependent modulation over a full 22-year solar magnetic cycle. Implications of these observations for our understanding of different modulation processes in the inner three-dimensional heliosphere are presented.

  1. Anomalous topography on the continental shelf around Hudson Canyon

    USGS Publications Warehouse

    Knebel, H.J.

    1979-01-01

    Recent seismic-reflection data show that the topography on the Continental Shelf around Hudson Canyon is composed of a series of depressions having variable spacings (< 100 m to 2 km), depths (1-10 m), outlines, and bottom configurations that give the sea floor an anomalous "jagged" appearance in profile. The acoustic and sedimentary characteristics, the proximity to relict shores, and the areal distribution indicate that this rough topography is an erosional surface formed on Upper Pleistocene silty sands about 13,000 to 15,000 years ago by processes related to Hudson Canyon. The pronounced southward extension of the surface, in particular, may reflect a former increase in the longshore-current erosion capacity caused by the loss of sediments over the canyon. Modern erosion or nondeposition of sediments has prevented the ubiquitous sand sheet on the Middle Atlantic shelf from covering the surface. The "anomalous" topography may, in fact, be characteristic of areas near other submarine canyons that interrupt or have interrupted the longshore drift of sediments. ?? 1979.

  2. The Frequency Evolution of Interstellar Pulse Broadening from Radio Pulsars

    NASA Astrophysics Data System (ADS)

    Löhmer, O.; Mitra, D.; Gupta, Y.; Kramer, M.; Ahuja, A.

    2004-10-01

    Using radio pulsars as probes of the interstellar medium (ISM) we study the frequency evolution of interstellar scattering. The frequency dependence of scatter broadening times, τsc, for most of the pulsars with low and intermediate dispersion measures (DM ≲ 400 pc cm-3) is consistent with the Kolmogorov spectrum of electron density fluctuations in a turbulent medium. In contrast, the measured τsc's for highly dispersed pulsars in the central region of the Galaxy are larger than expected and show a spectrum which is flatter than the Kolmogorov law. We analyse the first measurements of spectral indices of scatter broadening over the full known DM range and discuss possible explanations for the anomalous scattering behaviour along peculiar lines of sight (LOS).

  3. Anomalous behaviour of thermodynamic properties at successive phase transitions in (NH4)3GeF7

    NASA Astrophysics Data System (ADS)

    Bogdanov, Evgeniy V.; Kartashev, Andrey V.; Pogoreltsev, Evgeniy I.; Gorev, Mikhail V.; Laptash, Natalia M.; Flerov, Igor N.

    2017-12-01

    Heat capacity, thermal dilatation, susceptibility to hydrostatic pressure and dielectric properties associated with succession of three phase transitions below room temperature in double fluoride salt (NH4)3GeF7 were studied. A possible transformation into the parent Pm-3m cubic phase was not observed up to the decomposition of compound. Nonferroelectric nature of structural distortions was confirmed. The DTA under pressure studies revealed a high temperature stability of two phases: P4/mbm and Pbam. The entropies of the phase transitions agree well with the model of structural distortions. Analysis of the thermal properties associated with the individual phase transitions in the framework of thermodynamic equations has shown a high reliability of the data obtained.

  4. Hubbard pair cluster in the external fields. Studies of the magnetic properties

    NASA Astrophysics Data System (ADS)

    Balcerzak, T.; Szałowski, K.

    2018-06-01

    The magnetic properties of the two-site Hubbard cluster (dimer or pair), embedded in the external electric and magnetic fields and treated as the open system, are studied by means of the exact diagonalization of the Hamiltonian. The formalism of the grand canonical ensemble is adopted. The phase diagrams, on-site magnetizations, spin-spin correlations, mean occupation numbers and hopping energy are investigated and illustrated in figures. An influence of temperature, mean electron concentration, Coulomb U parameter and external fields on the quantities of interest is presented and discussed. In particular, the anomalous behaviour of the magnetization and correlation function vs. temperature near the critical magnetic field is found. Also, the effect of magnetization switching by the external fields is demonstrated.

  5. Defining the flexibility window in ordered aluminosilicate zeolites

    PubMed Central

    Wells, Stephen A.; Leung, Ka Ming; Edwards, Peter P.; Tucker, Matt G.

    2017-01-01

    The flexibility window in zeolites was originally identified using geometric simulation as a hypothetical property of SiO2 systems. The existence of the flexibility window in hypothetical structures may help us to identify those we might be able to synthesize in the future. We have previously found that the flexibility window in silicates is connected to phase transitions under pressure, structure amorphization and other physical behaviours and phenomena. We here extend the concept to ordered aluminosilicate systems using softer ‘bar’ constraints that permit additional flexibility around aluminium centres. Our experimental investigation of pressure-induced amorphization in sodalites is consistent with the results of our modelling. The softer constraints allow us to identify a flexibility window in the anomalous case of goosecreekite. PMID:28989777

  6. Particle acceleration with anomalous pitch angle scattering in 2D magnetohydrodynamic reconnection simulations

    NASA Astrophysics Data System (ADS)

    Borissov, A.; Kontar, E. P.; Threlfall, J.; Neukirch, T.

    2017-09-01

    The conversion of magnetic energy into other forms (such as plasma heating, bulk plasma flows, and non-thermal particles) during solar flares is one of the outstanding open problems in solar physics. It is generally accepted that magnetic reconnection plays a crucial role in these conversion processes. In order to achieve the rapid energy release required in solar flares, an anomalous resistivity, which is orders of magnitude higher than the Spitzer resistivity, is often used in magnetohydrodynamic (MHD) simulations of reconnection in the corona. The origin of Spitzer resistivity is based on Coulomb scattering, which becomes negligible at the high energies achieved by accelerated particles. As a result, simulations of particle acceleration in reconnection events are often performed in the absence of any interaction between accelerated particles and any background plasma. This need not be the case for scattering associated with anomalous resistivity caused by turbulence within solar flares, as the higher resistivity implies an elevated scattering rate. We present results of test particle calculations, with and without pitch angle scattering, subject to fields derived from MHD simulations of two-dimensional (2D) X-point reconnection. Scattering rates proportional to the ratio of the anomalous resistivity to the local Spitzer resistivity, as well as at fixed values, are considered. Pitch angle scattering, which is independent of the anomalous resistivity, causes higher maximum energies in comparison to those obtained without scattering. Scattering rates which are dependent on the local anomalous resistivity tend to produce fewer highly energised particles due to weaker scattering in the separatrices, even though scattering in the current sheet may be stronger when compared to resistivity-independent scattering. Strong scattering also causes an increase in the number of particles exiting the computational box in the reconnection outflow region, as opposed to along the separatrices as is the case in the absence of scattering.

  7. Fractional Diffusion Equations and Anomalous Diffusion

    NASA Astrophysics Data System (ADS)

    Evangelista, Luiz Roberto; Kaminski Lenzi, Ervin

    2018-01-01

    Preface; 1. Mathematical preliminaries; 2. A survey of the fractional calculus; 3. From normal to anomalous diffusion; 4. Fractional diffusion equations: elementary applications; 5. Fractional diffusion equations: surface effects; 6. Fractional nonlinear diffusion equation; 7. Anomalous diffusion: anisotropic case; 8. Fractional Schrödinger equations; 9. Anomalous diffusion and impedance spectroscopy; 10. The Poisson–Nernst–Planck anomalous (PNPA) models; References; Index.

  8. Anomalous nonlinear absorption in epsilon-near-zero materials: optical limiting and all-optical control.

    PubMed

    Vincenti, M A; de Ceglia, D; Scalora, Michael

    2016-08-01

    We investigate nonlinear absorption in films of epsilon-near-zero materials. The combination of large local electric fields at the fundamental frequency and material losses at the harmonic frequencies induce unusual intensity-dependent phenomena. We predict that the second-order nonlinearity of a low-damping, epsilon-near-zero slab produces an optical limiting effect that mimics a two-photon absorption process. Anomalous absorption profiles that depend on low permittivity values at the pump frequency are also predicted for third-order nonlinearities. These findings suggest new opportunities for all-optical light control and novel ways to design reconfigurable and tunable nonlinear devices.

  9. Muon g-2 Reconstruction and Analysis Framework for the Muon Anomalous Precession Frequency

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Khaw, Kim Siang

    The Muon g-2 experiment at Fermilab, with the aim to measure the muon anomalous magnetic moment to an unprecedented level of 140~ppb, has started beam and detector commissioning in Summer 2017. To deal with incoming data projected to be around tens of petabytes, a robust data reconstruction and analysis chain based on Fermilab's \\textit{art} event-processing framework is developed. Herein, I report the current status of the framework, together with its novel features such as multi-threaded algorithms for online data quality monitor (DQM) and fast-turnaround operation (nearline). Performance of the framework during the commissioning run is also discussed.

  10. Reason and reaction: the utility of a dual-focus, dual-processing perspective on promotion and prevention of adolescent health risk behaviour.

    PubMed

    Gibbons, Frederick X; Houlihan, Amy E; Gerrard, Meg

    2009-05-01

    A brief overview of theories of health behaviour that are based on the expectancy-value perspective is presented. This approach maintains that health behaviours are the result of a deliberative decision-making process that involves consideration of behavioural options along with anticipated outcomes associated with those options. It is argued that this perspective is effective at explaining and predicting many types of health behaviour, including health-promoting actions (e.g. UV protection, condom use, smoking cessation), but less effective at predicting risky health behaviours, such as unprotected, casual sex, drunk driving or binge drinking. These are behaviours that are less reasoned or premeditated - especially among adolescents. An argument is made for incorporating elements of dual-processing theories in an effort to improve the 'utility' of these models. Specifically, it is suggested that adolescent health behaviour involves both analytic and heuristic processing. Both types of processing are incorporated in the prototype-willingness (prototype) model, which is described in some detail. Studies of health behaviour based on the expectancy-value perspective (e.g. theory of reasoned action) are reviewed, along with studies based on the prototype model. These two sets of studies together suggest that the dual-processing perspective, in general, and the prototype model, in particular, add to the predictive validity of expectancy-value models for predicting adolescent health behaviour. Research and interventions that incorporate elements of dual-processing and elements of expectancy-value are more effective at explaining and changing adolescent health behaviour than are those based on expectancy-value theories alone.

  11. Automated defect spatial signature analysis for semiconductor manufacturing process

    DOEpatents

    Tobin, Jr., Kenneth W.; Gleason, Shaun S.; Karnowski, Thomas P.; Sari-Sarraf, Hamed

    1999-01-01

    An apparatus and method for performing automated defect spatial signature alysis on a data set representing defect coordinates and wafer processing information includes categorizing data from the data set into a plurality of high level categories, classifying the categorized data contained in each high level category into user-labeled signature events, and correlating the categorized, classified signature events to a present or incipient anomalous process condition.

  12. Anomalous-hydrodynamic analysis of charge-dependent elliptic flow in heavy-ion collisions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hongo, Masaru; Hirono, Yuji; Hirano, Tetsufumi

    Anomalous hydrodynamics is a low-energy effective theory that captures effects of quantum anomalies. We develop a numerical code of anomalous hydrodynamics and apply it to dynamics of heavy-ion collisions, where anomalous transports are expected to occur. This is the first attempt to perform fully non-linear numerical simulations of anomalous hydrodynamics. We discuss implications of the simulations for possible experimental observations of anomalous transport effects. From analyses of the charge-dependent elliptic flow parameters (vmore » $$±\\atop{2}$$) as a function of the net charge asymmetry A ±, we find that the linear dependence of Δv$$±\\atop{2}$$ ≡ v$$-\\atop{2}$$ - v$$+\\atop{2}$$ on the net charge asymmetry A ± cannot be regarded as a robust signal of anomalous transports, contrary to previous studies. We, however, find that the intercept Δv$$±\\atop{2}$$ (A ± = 0) is sensitive to anomalous transport effects.« less

  13. Anomalous-hydrodynamic analysis of charge-dependent elliptic flow in heavy-ion collisions

    DOE PAGES

    Hongo, Masaru; Hirono, Yuji; Hirano, Tetsufumi

    2017-12-10

    Anomalous hydrodynamics is a low-energy effective theory that captures effects of quantum anomalies. We develop a numerical code of anomalous hydrodynamics and apply it to dynamics of heavy-ion collisions, where anomalous transports are expected to occur. This is the first attempt to perform fully non-linear numerical simulations of anomalous hydrodynamics. We discuss implications of the simulations for possible experimental observations of anomalous transport effects. From analyses of the charge-dependent elliptic flow parameters (vmore » $$±\\atop{2}$$) as a function of the net charge asymmetry A ±, we find that the linear dependence of Δv$$±\\atop{2}$$ ≡ v$$-\\atop{2}$$ - v$$+\\atop{2}$$ on the net charge asymmetry A ± cannot be regarded as a robust signal of anomalous transports, contrary to previous studies. We, however, find that the intercept Δv$$±\\atop{2}$$ (A ± = 0) is sensitive to anomalous transport effects.« less

  14. TOPICAL REVIEW: The restaurant at the end of the random walk: recent developments in the description of anomalous transport by fractional dynamics

    NASA Astrophysics Data System (ADS)

    Metzler, Ralf; Klafter, Joseph

    2004-08-01

    Fractional dynamics has experienced a firm upswing during the past few years, having been forged into a mature framework in the theory of stochastic processes. A large number of research papers developing fractional dynamics further, or applying it to various systems have appeared since our first review article on the fractional Fokker-Planck equation (Metzler R and Klafter J 2000a, Phys. Rep. 339 1-77). It therefore appears timely to put these new works in a cohesive perspective. In this review we cover both the theoretical modelling of sub- and superdiffusive processes, placing emphasis on superdiffusion, and the discussion of applications such as the correct formulation of boundary value problems to obtain the first passage time density function. We also discuss extensively the occurrence of anomalous dynamics in various fields ranging from nanoscale over biological to geophysical and environmental systems.

  15. Al-26 from red giants. [connections with anomalous Mg-26 content in meteorites and solar system formation

    NASA Technical Reports Server (NTRS)

    Norgaard, H.

    1980-01-01

    Simplified models of thermally pulsing red giants are investigated, with particular emphasis on predicting the extent to which nuclear processing at the base of the convective envelope in conjunction with processing in the thermally unstable He shell can synthesize Al-26 (tau/1/2/ = 7.2 x 10 to the 5th yr). Values of Al-26/Al-27 of about 0.5-1, with Al-27/Al-27(solar) of about 1-2, are predicted in some cases. It is pointed out that such results can lead to isotope shifts in the absorption lines of AlH and AlO, which should be observationally identifiable in some late-type supergiants. The possible connection with the anomalous Mg-26 content (assigned to the decay of Al-26) detected in some meteorites and the connection with formation of the solar system are also touched on.

  16. Concentration-Encoded Subdiffusive Molecular Communication: Theory, Channel Characteristics, and Optimum Signal Detection.

    PubMed

    Mahfuz, Mohammad Upal; Makrakis, Dimitrios; Mouftah, Hussein T

    2016-09-01

    Unlike normal diffusion, in anomalous diffusion, the movement of a molecule is described by the correlated random walk model where the mean square displacement of a molecule depends on the power law of time. In molecular communication (MC), there are many scenarios when the propagation of molecules cannot be described by normal diffusion process, where anomalous diffusion is a better fit. In this paper, the effects of anomalous subdiffusion on concentration-encoded molecular communication (CEMC) are investigated. Although classical (i.e., normal) diffusion is a widely-used model of diffusion in molecular communication (MC) research, anomalous subdiffusion is quite common in biological media involving bio-nanomachines, yet inadequately addressed as a research issue so far. Using the fractional diffusion approach, the molecular propagation effects in the case of pure subdiffusion occurring in an unbounded three-dimensional propagation medium have been shown in detail in terms of temporal dispersion parameters of the impulse response of the subdiffusive channel. Correspondingly, the bit error rate (BER) performance of a CEMC system is investigated with sampling-based (SD) and strength (i.e., energy)-based (ED) signal detection methods. It is found that anomalous subdiffusion has distinctive time-dispersive properties that play a vital role in accurately designing a subdiffusive CEMC system. Unlike normal diffusion, to detect information symbols in subdiffusive CEMC, a receiver requires larger memory size to operate correctly and hence a more complex structure. An in-depth analysis has been made on the performances of SD and ED optimum receiver models under diffusion noise and intersymbol interference (ISI) scenarios when communication range, transmission data rate, and memory size vary. In subdiffusive CEMC, the SD method.

  17. Effects of urban land-use change in East China on the East Asian summer monsoon based on the CAM5.1 model

    NASA Astrophysics Data System (ADS)

    Ma, Hongyun; Jiang, Zhihong; Song, Jie; Dai, Aiguo; Yang, Xiuqun; Huo, Fei

    2016-05-01

    The effects of urban land-use change in East China on the East Asian summer monsoon (EASM) are investigated using a Community Atmosphere Model Version 5.1. The results show that the urban land-use change in East China causes spatially-varying changes in surface net radiation and heat fluxes, atmospheric circulation, and water budgets. It results in significant surface warming (cooling) and precipitation decrease (increase) in a large region north (south) of 30°N. Urban expansion agglomerated in (29°-41°N, 110°-122°E) alters the surface energy budget and warms the surface, resulting in strengthened southwesterly airflow south of 25°N and increased convergence below the mid-troposphere between 20° and 30°N. A concomitant northward downdraft associated with the increased convection generates an anomalous high pressure north of 30°N. Meanwhile, the downdraft not only produces adiabatic warming but also inhibits the dynamic condition for precipitation formation. The anomalous high pressure formed in North China prevents the southwesterly airflow from advancing northward, leading to increase the convergence and precipitation in South China. These changes reduce the meridional temperature gradient in the mid-lower troposphere and weaken the westerly airflow near 30°N. In addition, horizontal transport of vorticity north of 35°N weakens significantly, which leads to an anomalous barotropic structure of anticyclonic there. As a result, the anomalous anticyclonic circulation and descent north of 30°N are strengthened. At the same time, the anomalous cyclonic circulation and ascent south of 30°N are enhanced. These process induced by the thermal state changes due to urbanization weakens the EASM.

  18. Role of the meridional dipole of SSTA and associated cross-equatorial flow in the tropical eastern Pacific in terminating the 2014 El Niño development

    NASA Astrophysics Data System (ADS)

    Wu, Yi-Kai; Chen, Lin; Hong, Chi-Cherng; Li, Tim; Chen, Cheng-Ta; Wang, Lu

    2018-03-01

    In the boreal spring of 2014, the oceanic and atmospheric conditions were favorable for an El Niño's development. It was predicted that in 2014, a super El Niño or at least a regular El Niño with normal magnitude, would initiate. However, the growth rate of the sea surface temperature anomaly (SSTA) in the equatorial eastern Pacific suddenly declined in the boreal summer. The physical processes responsible for the termination of the 2014 El Niño were addressed in this study. We hypothesized that a meridional dipole of SSTA, characterized by a pronounced warm SSTA over the eastern North Pacific (ENP) and cold SSTA over the eastern South Pacific (ESP), played a crucial role in blocking the 2014 El Niño's development. The observational analysis revealed that the meridional dipole of SSTA and the relevant anomalous cross-equatorial flow in the tropical eastern Pacific, induced anomalous westward ({u^' }<0) and upwelling ({w^' }>0) currents in the equatorial eastern Pacific, leading to negative anomalous zonal advection term (- {u^' }partial \\overline T /partial x<0) and anomalous upwelling advection term (- {w^' }partial \\overline T /partial z<0). Additionally, the anomalous cross-equatorial flow also induced northward meridional current anomalies that transported subtropical cold water to the equator. All the changes of the oceanic dynamic terms collectively caused negative SSTA tendency in the boreal summer, and thus killed off the budding 2014 El Niño. The idealized numerical experiments further confirmed that the 2014 El Niño's development could be suppressed by the meridional dipole of SSTA, and both the ENP pole and ESP pole make a contribution.

  19. Compensation for red-green contrast loss in anomalous trichromats

    PubMed Central

    Boehm, A. E.; MacLeod, D. I. A.; Bosten, J. M.

    2014-01-01

    For anomalous trichromats, threshold contrasts for color differences captured by the L and M cones and their anomalous analogs are much higher than for normal trichromats. The greater spectral overlap of the cone sensitivities reduces chromatic contrast both at and above threshold. But above threshold, adaptively nonlinear processing might compensate for the chromatically impoverished photoreceptor inputs. Ratios of sensitivity for threshold variations and for color appearance along the two cardinal axes of MacLeod-Boynton chromaticity space were calculated for three groups: normals (N = 15), deuteranomals (N = 9), and protanomals (N = 5). Using a four-alternative forced choice (4AFC) task, threshold sensitivity was measured in four color-directions along the two cardinal axes. For the same participants, we reconstructed perceptual color spaces for the positions of 25 hues using multidimensional scaling (MDS). From the reconstructed color spaces we extracted “color difference ratios,” defined as ratios for the size of perceived color differences along the L/(L + M) axis relative to those along the S/(L + M) axis, analogous to “sensitivity ratios” extracted from the 4AFC task. In the 4AFC task, sensitivity ratios were 38% of normal for deuteranomals and 19% of normal for protanomals. Yet, in the MDS results, color difference ratios were 86% of normal for deuteranomals and 67% of normal for protanomals. Thus, the contraction along the L/(L + M) axis shown in the perceptual color spaces of anomalous trichromats is far smaller than predicted by their reduced sensitivity, suggesting that an adaptive adjustment of postreceptoral gain may magnify the cone signals of anomalous trichromats to exploit the range of available postreceptoral neural signals. PMID:25413625

  20. Deficient Behavioral Inhibition and Anomalous Selective Attention in a Community Sample of Adolescents with Psychopathic Traits and Low-Anxiety Traits

    ERIC Educational Resources Information Center

    Vitale, Jennifer E.; Newman, Joseph P.; Bates, John E.; Goodnight, Jackson; Dodge, Kenneth A.; Pettit, Gregory S.

    2005-01-01

    Socialization is the important process by which individuals learn and then effectively apply the rules of appropriate societal behavior. Response modulation is a psychobiological process theorized to aid in socialization by allowing individuals to utilize contextual information to modify ongoing behavior appropriately. Using Hare's (1991)…

  1. Brief Report: Anomalous Neural Deactivations and Functional Connectivity during Receptive Language in Autism Spectrum Disorder--A Functional MRI Study

    ERIC Educational Resources Information Center

    Karten, Ariel; Hirsch, Joy

    2015-01-01

    Neural mechanisms that underlie language disability in autism spectrum disorder (ASD) have been associated with reduced excitatory processes observed as positive blood oxygen level dependent (BOLD) responses. However, negative BOLD responses (NBR) associated with language and inhibitory processes have been less studied in ASD. In this study,…

  2. Sensitivity and Bias in Decision-Making under Risk: Evaluating the Perception of Reward, Its Probability and Value

    PubMed Central

    Sharp, Madeleine E.; Viswanathan, Jayalakshmi; Lanyon, Linda J.; Barton, Jason J. S.

    2012-01-01

    Background There are few clinical tools that assess decision-making under risk. Tests that characterize sensitivity and bias in decisions between prospects varying in magnitude and probability of gain may provide insights in conditions with anomalous reward-related behaviour. Objective We designed a simple test of how subjects integrate information about the magnitude and the probability of reward, which can determine discriminative thresholds and choice bias in decisions under risk. Design/Methods Twenty subjects were required to choose between two explicitly described prospects, one with higher probability but lower magnitude of reward than the other, with the difference in expected value between the two prospects varying from 3 to 23%. Results Subjects showed a mean threshold sensitivity of 43% difference in expected value. Regarding choice bias, there was a ‘risk premium’ of 38%, indicating a tendency to choose higher probability over higher reward. An analysis using prospect theory showed that this risk premium is the predicted outcome of hypothesized non-linearities in the subjective perception of reward value and probability. Conclusions This simple test provides a robust measure of discriminative value thresholds and biases in decisions under risk. Prospect theory can also make predictions about decisions when subjective perception of reward or probability is anomalous, as may occur in populations with dopaminergic or striatal dysfunction, such as Parkinson's disease and schizophrenia. PMID:22493669

  3. Anomalous atomic displacement parameters and local dynamics in the Curie range of a Pb-free relaxor ferroelectric system (Bi1-xBax)(Fe1-xTix)O3(0.36 ≤ x ≤ 0.50)

    NASA Astrophysics Data System (ADS)

    Singh, Anar; Moriyoshi, Chikako; Kuroiwa, Yoshihiro; Pandey, Dhananjai

    2018-04-01

    We report here the relaxor ferroelectric (RFE) behaviour in a multiferroic solid solution system, (Bi1-xBax)(Fe1-xTix)O3, at a critical disorder level of xC ˜ 0.35 in BiFeO3 and 0.65 (i.e., 1-xC = 0.35) in BaTiO3 similar to the 1:2 ratio of Mg2+ and Nb5+ in the canonical RFE Pb(Mg1/3Nb2/3)O3. This Pb-free system, like canonical Pb-based RFEs, does not exhibit macroscopic symmetry breaking and shows only the signatures of ergodicity breaking at Vogel-Fulcher freezing temperature (TVF). The atomic displacement parameters (ADPs) of Fe3+/Ti4+ and O2-, obtained using high wave vector (Q) and high-resolution synchrotron x-ray diffraction data as a function of temperature, show anomalous diffuse peaks in the Curie range. It is shown that the diffuse peak in ADPs is due to softening of the vibrational frequencies of the B-O chain (B = Fe3+/Ti4+ and O = O2-) below the Burns temperature (TB) followed by hardening below the characteristic temperature (T'm), which corresponds to a peak in the dielectric permittivity (ɛ').

  4. Thermoluminescence characteristics of a chondrite (Holbrook) and an aubrite achondrite (Norton County) meteorites.

    PubMed

    Bossin, Lily; Kazakis, Nikolaos A; Kitis, George; Tsirliganis, Nestor C

    2017-09-01

    The present study constitutes the first part of a meteorite project, currently in progress, towards the full and thorough dosimetric study (TL and OSL) of two different meteorites of recent fall, Norton County and Holbrook. Both meteorites exhibit strong TL sensitivity, linear dose response and no saturation for doses up to 2kGy. However, the two meteorites exhibited a very dissimilar TL glow curve and behaviour regarding sensitization and fading. Notably, the Norton County aubrite achondrite was found to exhibit a strong fading of the high-temperature peak (~300°C), attributed to anomalous fading, whereas Holbrook did not seem to show signs of anomalous fading. Since quantitative conclusions regarding the thermal and irradiation history of meteorites, require knowledge of the detailed peak structure of the glow curve and deeper understanding of the trapping mechanism, the glow curves, after irradiation in the range 10-2000Gy, were deconvoluted using general order kinetics. The fitting parameters extracted point towards complex non-strictly first order mechanisms with a multitude of traps acting very differently. All the above, combined with future OSL measurements, currently in progress, are expected to shed light on the nature of the involved traps in both phenomena (energy depth, light-resistance etc), which would allow to extract more concrete conclusions about their history. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Sensitivity and bias in decision-making under risk: evaluating the perception of reward, its probability and value.

    PubMed

    Sharp, Madeleine E; Viswanathan, Jayalakshmi; Lanyon, Linda J; Barton, Jason J S

    2012-01-01

    There are few clinical tools that assess decision-making under risk. Tests that characterize sensitivity and bias in decisions between prospects varying in magnitude and probability of gain may provide insights in conditions with anomalous reward-related behaviour. We designed a simple test of how subjects integrate information about the magnitude and the probability of reward, which can determine discriminative thresholds and choice bias in decisions under risk. Twenty subjects were required to choose between two explicitly described prospects, one with higher probability but lower magnitude of reward than the other, with the difference in expected value between the two prospects varying from 3 to 23%. Subjects showed a mean threshold sensitivity of 43% difference in expected value. Regarding choice bias, there was a 'risk premium' of 38%, indicating a tendency to choose higher probability over higher reward. An analysis using prospect theory showed that this risk premium is the predicted outcome of hypothesized non-linearities in the subjective perception of reward value and probability. This simple test provides a robust measure of discriminative value thresholds and biases in decisions under risk. Prospect theory can also make predictions about decisions when subjective perception of reward or probability is anomalous, as may occur in populations with dopaminergic or striatal dysfunction, such as Parkinson's disease and schizophrenia.

  6. Possible Connection of Geological Composition With Geomagnetic Field Change In Kopaonik Thrust Region

    NASA Astrophysics Data System (ADS)

    Popeskov, Mirjana; Cukavac, Milena; Lazovic, Caslav

    This paper should consider interpretation of geomagnetic field changes on the basis of possible connection with geological composition of deformation zone. Analysis of total magnetic field intensity data from 38 surveys, carried out in the period may 1980 ­ november 2001 in Kopaonik thrust region, central Serbia, reveals anomalous behaviour of local field changes in particular time intervals. These data give us possibility to observe geomagnetic changes in long period of time. This paper shall consider if and how different magnetizations of geological composition of array are in connection with anomalous geomagnetic field change. We shall consider how non-uniform geological structure or rocks with different magnetizations can effect geomagnetic observations and weather sharp contrast in rock magnetization between neighbour layers can give rise to larger changes in the geomagnetic total intensity than those for a uniform layer. For that purpose we are going to consider geological and tectonical map of Kopaonik region. We shall also consider map of vertical component of geomagnetic field because Kopaonik belongs to high magnetic anomaly zone. Corelation of geomagnetic and geological data is supposed to give us some answers to the question of origine of some anomalious geomagnetic changes in total intensity of geomagnetic field. It can also represent first step in corelationof geomagnetic field changes to other geophysical, seismological or geological data that can be couse of geomagnetic field change.

  7. Anomalous magnetoelastic behaviour near morphotropic phase boundary in ferromagnetic Tb{sub 1-x}Nd{sub x}Co{sub 2} system

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Murtaza, Adil; Yang, Sen, E-mail: yang.sen@mail.xjtu.edu.cn; Zhou, Chao

    2016-08-01

    In this work, we report a morphotropic phase boundary (MPB) involved ferromagnetic system Tb{sub 1-x}Nd{sub x}Co{sub 2} and reveal the corresponding structural and magnetoelastic properties of this system. With high resolution synchrotron X-ray diffractometry, the crystal structure of the TbCo{sub 2}-rich side is detected to be rhombohedral and that of NdCo{sub 2}-rich side is tetragonal below their respective Curie temperatures T{sub C}. The MPB composition Tb{sub 0.35}Nd{sub 0.65}Co{sub 2} corresponds to the coexistence of the rhombohedral phase (R-phase) and tetragonal phase (T-phase). Contrary to previously reported MPB involved ferromagnetic systems, the MPB composition of Tb{sub 0.35}Nd{sub 0.65}Co{sub 2} shows minimummore » magnetization which can be understood as compensation of sublattice moments between the R-phase and the T-phase. Furthermore, magnetostriction of Tb{sub 1-x}Nd{sub x}Co{sub 2} decreases with increasing Nd concentration until x = 0.8 and then increases in the negative direction with further increasing Nd concentration; the optimum point for magnetoelastic properties lies towards the rhombohedral phase. Our work not only shows an anomalous type of ferromagnetic MPB but also provides an effective way to design functional materials.« less

  8. Continuous time anomalous diffusion in a composite medium.

    PubMed

    Stickler, B A; Schachinger, E

    2011-08-01

    The one-dimensional continuous time anomalous diffusion in composite media consisting of a finite number of layers in immediate contact is investigated. The diffusion process itself is described with the help of two probability density functions (PDFs), one of which is an arbitrary jump-length PDF, and the other is a long-tailed waiting-time PDF characterized by the waiting-time index β∈(0,1). The former is assumed to be a function of the space coordinate x and the time coordinate t while the latter is a function of x and the time interval. For such an environment a very general form of the diffusion equation is derived which describes the continuous time anomalous diffusion in a composite medium. This result is then specialized to two particular forms of the jump-length PDF, namely the continuous time Lévy flight PDF and the continuous time truncated Lévy flight PDF. In both cases the PDFs are characterized by the Lévy index α∈(0,2) which is regarded to be a function of x and t. It is possible to demonstrate that for particular choices of the indices α and β other equations for anomalous diffusion, well known from the literature, follow immediately. This demonstrates the very general applicability of the derivation and of the resulting fractional differential equation discussed here.

  9. Spectral-decomposition techniques for the identification of periodic and anomalous phenomena in radon time-series.

    NASA Astrophysics Data System (ADS)

    Crockett, R. G. M.; Perrier, F.; Richon, P.

    2009-04-01

    Building on independent investigations by research groups at both IPGP, France, and the University of Northampton, UK, hourly-sampled radon time-series of durations exceeding one year have been investigated for periodic and anomalous phenomena using a variety of established and novel techniques. These time-series have been recorded in locations having no routine human behaviour and thus are effectively free of significant anthropogenic influences. With regard to periodic components, the long durations of these time-series allow, in principle, very high frequency resolutions for established spectral-measurement techniques such as Fourier and maximum-entropy. However, as has been widely observed, the stochastic nature of radon emissions from rocks and soils, coupled with sensitivity to a wide variety influences such as temperature, wind-speed and soil moisture-content has made interpretation of the results obtained by such techniques very difficult, with uncertain results, in many cases. We here report developments in the investigation of radon-time series for periodic and anomalous phenomena using spectral-decomposition techniques. These techniques, in variously separating ‘high', ‘middle' and ‘low' frequency components, effectively ‘de-noise' the data by allowing components of interest to be isolated from others which (might) serve to obscure weaker information-containing components. Once isolated, these components can be investigated using a variety of techniques. Whilst this is very much work in early stages of development, spectral decomposition methods have been used successfully to indicate the presence of diurnal and sub-diurnal cycles in radon concentration which we provisionally attribute to tidal influences. Also, these methods have been used to enhance the identification of short-duration anomalies, attributable to a variety of causes including, for example, earthquakes and rapid large-magnitude changes in weather conditions. Keywords: radon; earthquakes; tidal-influences; anomalies; time series; spectral-decomposition.

  10. Inattentive behaviour is associated with poor working memory and slow processing speed in very pre-term children in middle childhood.

    PubMed

    Mulder, Hanna; Pitchford, Nicola J; Marlow, Neil

    2011-03-01

    BACKGROUND. Problem behaviour is common following pre-term birth, but the underlying nature of these difficulties is not well known. AIMS. We sought to establish the mechanisms underpinning behavioural difficulties in very pre-term (VPT) children in middle childhood by comparing their performance to that of term born peers on tasks of working memory, inhibition, and processing speed, and relating these to parent and teacher assessments of their behaviour. Particular focus was given to inattention and overactive/impulsive behaviour, as these behaviours have been associated with different neuropsychological problems in term children. SAMPLES. A group of VPT children (gestational age < 31 weeks, N= 56) aged 9-10 years and term controls (N= 22) participated in the study. METHOD. Children were assessed with measures of working memory, inhibition, and processing speed. Parents and teachers reported behavioural problems using the Strengths and Difficulties Questionnaire and two additional scales measuring overactive/impulsive behaviour and inattention. RESULTS. Results revealed increased rates of problem behaviour in VPT compared to term children for parent-rated total difficulties, hyperactivity, emotional problems, peer problems, prosocial behaviour, overactive/impulsive behaviour, and parent- and teacher-rated inattention. Processing speed and working memory, but not inhibition, were significantly related to inattentive and overactive/impulsive behaviour. CONCLUSIONS. The increased rates of inattention and overactive/impulsive behaviour in VPT children may be explained by impairment in processing speed and working memory. Expected links between overactive/impulsive behaviour and inhibitory control were not identified, suggesting the nature of such difficulties may be different in VPT compared to term children. © 2010 The British Psychological Society.

  11. Anomalous-hydrodynamic analysis of charge-dependent elliptic flow in heavy-ion collisions

    NASA Astrophysics Data System (ADS)

    Hongo, Masaru; Hirono, Yuji; Hirano, Tetsufumi

    2017-12-01

    Anomalous hydrodynamics is a low-energy effective theory that captures effects of quantum anomalies. We develop a numerical code of ideal anomalous hydrodynamics and apply it to dynamics of heavy-ion collisions, where anomalous transports are expected to occur. We discuss implications of the simulations for possible experimental observations of anomalous transport effects. From analyses of the charge-dependent elliptic flow parameters (v2±) as a function of the net charge asymmetry A±, we find that the linear dependence of Δ v2± ≡ v2- - v2+ on the net charge asymmetry A± can come from a mechanism unrelated to anomalous transport effects. Instead, we find that a finite intercept Δ v2± (A± = 0) can come from anomalous effects.

  12. Upscaling anomalous reactive kinetics (A+B-->C) from pore scale Lagrangian velocity analysis

    NASA Astrophysics Data System (ADS)

    De Anna, P.; Tartakovsky, A. M.; Le Borgne, T.; Dentz, M.

    2011-12-01

    Natural flow fields in porous media display a complex spatio-temporal organization due to heterogeneous geological structures at different scales. This multiscale disorder implies anomalous dispersion, mixing and reaction kinetics (Berkowitz et al. RG 2006, Tartakovsky PRE 2010). Here, we focus on the upscaling of anomalous kinetics arising from pore scale, non Gaussian and correlated, velocity distributions. We consider reactive front simulations, where a component A displaces a component B that saturates initially the porous domain. The reactive component C is produced at the dispersive front located at interface between the A and B domains. The simulations are performed with the SPH method. As the mixing zone grows, the total mass of C produced increases with time. The scaling of this evolution with time is different from that which would be obtained from the homogeneous advection dispersion reaction equation. This anomalous kinetics property is related to spatial structure of the reactive mixture, and its evolution with time under the combined action of advective and diffusive processes. We discuss the different scaling regimes arising depending on the dominant process that governs mixing. In order to upscale these processes, we analyze the Lagrangian velocity properties, which are characterized by the non Gaussian distributions and long range temporal correlation. The main origin of these properties is the existence of very low velocity regions where solute particles can remain trapped for a long time. Another source of strong correlation is the channeling of flow in localized high velocity regions, which created finger-like structures in the concentration field. We show the spatial Markovian, and temporal non Markovian, nature of the Lagrangian velocity field. Therefore, an upscaled model can be defined as a correlated Continuous Time Random Walk (Le Borgne et al. PRL 2008). A key feature of this model is the definition of a transition probability density for Lagrangian velocities across a characteristic correlation distance. We quantify this transition probability density from pore scale simulations and use it in the effective stochastic model. In this framework, we investigate the ability of this effective model to represent correctly dispersion and mixing.

  13. Differences observed in the surface morphology and microstructure of Ni-Fe-Cu ternary thin films electrochemically deposited at low and high applied current densities

    NASA Astrophysics Data System (ADS)

    Sarac, U.; Kaya, M.; Baykul, M. C.

    2016-10-01

    In this research, nanocrystalline Ni-Fe-Cu ternary thin films using electrochemical deposition technique were produced at low and high applied current densities onto Indium Tin Oxide (ITO) coated conducting glass substrates. Change of surface morphology and microstructural properties of the films were investigated. Energy dispersive X-ray spectroscopy (EDX) measurements showed that the Ni-Fe-Cu ternary thin films exhibit anomalous codeposition behaviour during the electrochemical deposition process. From the X-ray diffraction (XRD) analyses, it was revealed that there are two segregated phases such as Cu- rich and Ni-rich within the films. The crystallographic structure of the films was face-centered cubic (FCC). It was also observed that the film has lower lattice micro-strain and higher texture degree at high applied current density. Scanning electron microscopy (SEM) studies revealed that the films have rounded shape particles on the base part and cauliflower-like structures on the upper part. The film electrodeposited at high current density had considerably smaller rounded shape particles and cauliflower-like structures. From the atomic force microscopy (AFM) analyses, it was shown that the film deposited at high current density has smaller particle size and surface roughness than the film grown at low current density.

  14. Anomalous heat conduction and anomalous diffusion in nonlinear lattices, single walled nanotubes, and billiard gas channels.

    PubMed

    Li, Baowen; Wang, Jiao; Wang, Lei; Zhang, Gang

    2005-03-01

    We study anomalous heat conduction and anomalous diffusion in low-dimensional systems ranging from nonlinear lattices, single walled carbon nanotubes, to billiard gas channels. We find that in all discussed systems, the anomalous heat conductivity can be connected with the anomalous diffusion, namely, if energy diffusion is sigma(2)(t)=2Dt(alpha) (01) implies an anomalous heat conduction with a divergent thermal conductivity (beta>0), and more interestingly, a subdiffusion (alpha<1) implies an anomalous heat conduction with a convergent thermal conductivity (beta<0), consequently, the system is a thermal insulator in the thermodynamic limit. Existing numerical data support our theoretical prediction.

  15. Effect of NiO substitution on the structural and dielectric behaviour of NaNbO3

    NASA Astrophysics Data System (ADS)

    George, R. T.; Joshi, D. C.; Nayak, S.; Tiwari, N.; Chauhan, R. N.; Pramanik, P.; Dar, T. A.; Ghosh, S.; Thota, S.

    2018-02-01

    The structural and dielectric properties of NiO substituted NaNbO3 ceramics are reported. The orthorhombic (Pmna) crystal structure of NaNbO3 transforms to a lower symmetry monoclinic phase (Pbma) after the dilute dispersion of NiO. X-ray photoelectron spectroscopy reveals pentavalent "Nb," monovalent "Na," and divalent "Ni" states along with the signatures of non-local screening effects. The antiferroelectric to paraelectric transition (TAFE) accompanied by a structural change from the orthorhombic to the tetragonal phase shifts by 55 °C toward the low-temperature side, whereas the morphotropic phase boundary (TO-M) moves toward a higher temperature by 28 °C for nominal substitutions ( x ≤0.10 ). The generalized Lyddane-Sachs-Teller expression (ε0/-S'ε∞)= (ωl/ωt ) 2 and thermodynamic free energy models are employed to explain the anomalous behaviour of the temperature dependence of relative dielectric permittivity ( εr (T)) across TAFE and TO-M. The frequency dependence of ac-conductivity σac(ω) follows the Jonscher power law (σac = σ(0) + Aωs), suggesting the dominance of the phonon-assisted hopping mechanism, whereas the frequency independent term (σ(0)) was explained by Funke's Jump-Relaxation Model.

  16. Wanted: A Positive Control for Anomalous Subdiffusion

    PubMed Central

    Saxton, Michael J.

    2012-01-01

    Anomalous subdiffusion in cells and model systems is an active area of research. The main questions are whether diffusion is anomalous or normal, and if it is anomalous, its mechanism. The subject is controversial, especially the hypothesis that crowding causes anomalous subdiffusion. Anomalous subdiffusion measurements would be strengthened by an experimental standard, particularly one able to cross-calibrate the different types of measurements. Criteria for a calibration standard are proposed. First, diffusion must be anomalous over the length and timescales of the different measurements. The length-scale is fundamental; the time scale can be adjusted through the viscosity of the medium. Second, the standard must be theoretically well understood, with a known anomalous subdiffusion exponent, ideally readily tunable. Third, the standard must be simple, reproducible, and independently characterizable (by, for example, electron microscopy for nanostructures). Candidate experimental standards are evaluated, including obstructed lipid bilayers; aqueous systems obstructed by nanopillars; a continuum percolation system in which a prescribed fraction of randomly chosen obstacles in a regular array is ablated; single-file diffusion in pores; transient anomalous subdiffusion due to binding of particles in arrays such as transcription factors in randomized DNA arrays; and computer-generated physical trajectories. PMID:23260043

  17. Using Statistical Process Control for detecting anomalies in multivariate spatiotemporal Earth Observations

    NASA Astrophysics Data System (ADS)

    Flach, Milan; Mahecha, Miguel; Gans, Fabian; Rodner, Erik; Bodesheim, Paul; Guanche-Garcia, Yanira; Brenning, Alexander; Denzler, Joachim; Reichstein, Markus

    2016-04-01

    The number of available Earth observations (EOs) is currently substantially increasing. Detecting anomalous patterns in these multivariate time series is an important step in identifying changes in the underlying dynamical system. Likewise, data quality issues might result in anomalous multivariate data constellations and have to be identified before corrupting subsequent analyses. In industrial application a common strategy is to monitor production chains with several sensors coupled to some statistical process control (SPC) algorithm. The basic idea is to raise an alarm when these sensor data depict some anomalous pattern according to the SPC, i.e. the production chain is considered 'out of control'. In fact, the industrial applications are conceptually similar to the on-line monitoring of EOs. However, algorithms used in the context of SPC or process monitoring are rarely considered for supervising multivariate spatio-temporal Earth observations. The objective of this study is to exploit the potential and transferability of SPC concepts to Earth system applications. We compare a range of different algorithms typically applied by SPC systems and evaluate their capability to detect e.g. known extreme events in land surface processes. Specifically two main issues are addressed: (1) identifying the most suitable combination of data pre-processing and detection algorithm for a specific type of event and (2) analyzing the limits of the individual approaches with respect to the magnitude, spatio-temporal size of the event as well as the data's signal to noise ratio. Extensive artificial data sets that represent the typical properties of Earth observations are used in this study. Our results show that the majority of the algorithms used can be considered for the detection of multivariate spatiotemporal events and directly transferred to real Earth observation data as currently assembled in different projects at the European scale, e.g. http://baci-h2020.eu/index.php/ and http://earthsystemdatacube.net/. Known anomalies such as the Russian heatwave are detected as well as anomalies which are not detectable with univariate methods.

  18. Fully interferometric controllable anomalous refraction efficiency using cross modulation with plasmonic metasurfaces.

    PubMed

    Liu, Zhaocheng; Chen, Shuqi; Li, Jianxiong; Cheng, Hua; Li, Zhancheng; Liu, Wenwei; Yu, Ping; Xia, Ji; Tian, Jianguo

    2014-12-01

    We present a method of fully interferometric, controllable anomalous refraction efficiency by introducing cross-modulated incident light based on plasmonic metasurfaces. Theoretical analyses and numerical simulations indicate that the anomalous and ordinary refracted beams generated from two opposite-helicity incident beams and following the generalized Snell's law will have a superposition for certain incident angles, and the anomalous refraction efficiency can be dynamically controlled by changing the relative phase of the incident sources. As the incident wavelength nears the resonant wavelength of the plasmonic metasurfaces, two equal-amplitude incident beams with opposite helicity can be used to control the anomalous refraction efficiency. Otherwise, two unequal-amplitude incident beams with opposite helicity can be used to fully control the anomalous refraction efficiency. This Letter may offer a further step in the development of controllable anomalous refraction.

  19. Tuning of thermoelectric properties with changing Se content in Sb2Te3

    NASA Astrophysics Data System (ADS)

    Das, D.; Malik, K.; Deb, A. K.; Kulbachinskii, V. A.; Kytin, V. G.; Chatterjee, S.; Das, D.; Dhara, S.; Bandyopadhyay, S.; Banerjee, A.

    2016-02-01

    Polycrystalline Sb2Te3-x Se x (0.0≤ x≤1.0) samples were synthesized by the solid-state reaction method. The structural analysis showed that up to the maximal concentration of Se, the samples possess rhombohedral crystal symmetry (space group R\\bar{3}m ). The increase of Se content increases the resistivity of the samples. The variation of phonon frequencies, observed from the Raman spectroscopic study, depicts an anomalous behaviour around x=0.2 . The sample Sb2Te2.8Se0.2 also shows maximum Seebeck coefficient, carrier concentration and thermoelectric power factor. The nature of the scattering mechanism controlling the thermopower data has been explored. The thermoelectric properties of the synthesized materials have been analyzed theoretically in the frame of the Boltzmann equation approach.

  20. Activation energy and entropy for viscosity of wormlike micelle solutions.

    PubMed

    Chandler, H D

    2013-11-01

    The viscosities of two surfactant solutions which form wormlike micelles (WLMs) were studied over a range of temperatures and strain rates. WLM solutions appear to differ from many other shear thinning systems in that, as the shear rate increases, stress-shear rate curves tend to converge with temperature rather than diverge and this can sometimes lead to higher temperature curves crossing those at lower. Behaviour was analysed in terms of activation kinetics. It is suggested that two mechanisms are involved: Newtonian flow, following an Arrhenius law superimposed on a non-Newtonian flow described by a stress assisted kinetic law, this being a more general form of the Arrhenius law. Anomalous flow is introduced into the kinetic equation via a stress dependent activation entropy term. Copyright © 2013 Elsevier Inc. All rights reserved.

  1. Superconductivity and anomalous normal state in the CePd 2Si 2/CeNi 2Ge 2 system

    NASA Astrophysics Data System (ADS)

    Grosche, F. M.; Lister, S. J. S.; Carter, F. V.; Saxena, S. S.; Haselwimmer, R. K. W.; Mathur, N. D.; Julian, S. R.; Lonzarich, G. G.

    1997-02-01

    The unconventional nonmagnetic metal CeNi 2Ge 2 is characterised at ambient pressure by temperature dependences of the specific heat and of the resistivity which deviate strongly from standard Fermi-liquid predictions and are reminiscent of the behaviour observed in its sibling system CePd 2Si 2 above the critical pressure at which magnetic order is suppressed. We have explored the CePd 2Si 2/CeNi 2Ge 2 phase diagram in a series of resistivity measurements under high hydrostatic pressure, p. At p > 15 kbar, a new superconducting transition appears below 220 mK in CeNi 2Ge 2 and shifts to higher temperatures with increasing pressure, reaching ≈400 mK at p ≈ 26 kbar.

  2. Cows Come Down from the Mountains before the (Mw = 6.1) Earthquake Colfiorito in September 1997; A Single Case Study

    PubMed Central

    Fidani, Cristiano; Freund, Friedemann; Grant, Rachel

    2014-01-01

    Simple Summary Recent reports from several countries such as China, Italy and Japan support the existence of strange animal behaviour before strong earthquakes. However, the stimuli to which animals are sensitive preceding seismic activity are still not completely understood. Here we report the case of a herd of cows (reported by an entire village) leaving the hill pasture and descending near to the village streets two days before a strong earthquake. Abstract The September–October 1997 seismic sequence in the Umbria–Marche regions of Central Italy has been one of the stronger seismic events to occur in Italy over the last thirty years, with a maximum magnitude of Mw = 6.1. Over the last three years, a collection of evidence was carried out regarding non-seismic phenomena, by interviewing local residents using a questionnaire. One particular observation of anomalous animal behaviour, confirmed by many witnesses, concerned a herd of cows, which descended from a mountain close to the streets of a village near the epicentre, a few days before the main shock. Testimonies were collected using a specific questionnaire including data on earthquake lights, spring variations, human diseases, and irregular animal behaviour. The questionnaire was compiled after the L’Aquila earthquake in 2009, and was based upon past historical earthquake observations. A possible explanation for the cows’ behavior—local air ionization caused by stress-activated positive holes—is discussed. PMID:26480042

  3. Fourier Thermal Analysis of the Eutectic Formed in Pb-Sn Alloys

    NASA Astrophysics Data System (ADS)

    Cruz, H.; Ramírez-Argaez, M.; Juarez, A.; Garcia, A.; González-Rivera, C.

    2009-06-01

    The effect of the presence of two different primary phases on the microstructural characteristics and solidification kinetics of Pb-Sn eutectic was analyzed using Fourier thermal analysis method (FTA) and microstructural characterization. Three Pb-Sn alloys, a hypoeutectic, an eutectic, and a hypereutectic alloy, were melted in an electric furnace under an argon atmosphere and poured into sand molds. Cooling curves were obtained and numerically processed using FTA. Microstructural observations of the probes indicate a lamellar morphology for the eutectic microconstituent of the hypereutectic alloy; the eutectic alloy shows the presence of both lamellar and anomalous eutectic and the hypoeutectic alloy shows only the presence of anomalous eutectic. FTA results indicate that in the case of the probes showing the presence of anomalous eutectic, there is a primary eutectic formed during recalescence at high undercooling and a secondary eutectic yielded at low undercooling at the eutectic plateau temperature. This result shows that the cause behind the observed differences in the eutectic morphologies of the experimental alloys lies on the nucleating ability of the primary phase available as a potential substrate for nucleation of the eutectic microconstituent.

  4. Zγ production at NNLO including anomalous couplings

    NASA Astrophysics Data System (ADS)

    Campbell, John M.; Neumann, Tobias; Williams, Ciaran

    2017-11-01

    In this paper we present a next-to-next-to-leading order (NNLO) QCD calculation of the processes pp → l + l -γ and pp\\to ν \\overline{ν}γ that we have implemented in MCFM. Our calculation includes QCD corrections at NNLO both for the Standard Model (SM) and additionally in the presence of Zγγ and ZZγ anomalous couplings. We compare our implementation, obtained using the jettiness slicing approach, with a previous SM calculation and find broad agreement. Focusing on the sensitivity of our results to the slicing parameter, we show that using our setup we are able to compute NNLO cross sections with numerical uncertainties of about 0.1%, which is small compared to residual scale uncertainties of a few percent. We study potential improvements using two different jettiness definitions and the inclusion of power corrections. At √{s}=13 TeV we present phenomenological results and consider Zγ as a background to H → Zγ production. We find that, with typical cuts, the inclusion of NNLO corrections represents a small effect and loosens the extraction of limits on anomalous couplings by about 10%.

  5. Early inner solar system origin for anomalous sulfur isotopes in differentiated protoplanets.

    PubMed

    Antonelli, Michael A; Kim, Sang-Tae; Peters, Marc; Labidi, Jabrane; Cartigny, Pierre; Walker, Richard J; Lyons, James R; Hoek, Joost; Farquhar, James

    2014-12-16

    Achondrite meteorites have anomalous enrichments in (33)S, relative to chondrites, which have been attributed to photochemistry in the solar nebula. However, the putative photochemical reactions remain elusive, and predicted accompanying (33)S depletions have not previously been found, which could indicate an erroneous assumption regarding the origins of the (33)S anomalies, or of the bulk solar system S-isotope composition. Here, we report well-resolved anomalous (33)S depletions in IIIF iron meteorites (<-0.02 per mil), and (33)S enrichments in other magmatic iron meteorite groups. The (33)S depletions support the idea that differentiated planetesimals inherited sulfur that was photochemically derived from gases in the early inner solar system (<∼2 AU), and that bulk inner solar system S-isotope composition was chondritic (consistent with IAB iron meteorites, Earth, Moon, and Mars). The range of mass-independent sulfur isotope compositions may reflect spatial or temporal changes influenced by photochemical processes. A tentative correlation between S isotopes and Hf-W core segregation ages suggests that the two systems may be influenced by common factors, such as nebular location and volatile content.

  6. Monte Carlo investigation of anomalous transport in presence of a discontinuity and of an advection field

    NASA Astrophysics Data System (ADS)

    Marseguerra, M.; Zoia, A.

    2007-04-01

    Anomalous diffusion has recently turned out to be almost ubiquitous in transport problems. When the physical properties of the medium where the transport process takes place are stationary and constant at each spatial location, anomalous transport has been successfully analysed within the Continuous Time Random Walk (CTRW) model. In this paper, within a Monte Carlo approach to CTRW, we focus on the particle transport through two regions characterized by different physical properties, in presence of an external driving action constituted by an additional advective field, modelled within both the Galilei invariant and Galilei variant schemes. Particular attention is paid to the interplay between the distributions of space and time across the discontinuity. The resident concentration and the flux of the particles are finally evaluated and it is shown that at the interface between the two regions the flux is continuous as required by mass conservation, while the concentration may reveal a neat discontinuity. This result could open the route to the Monte Carlo investigation of the effectiveness of a physical discontinuity acting as a filter on particle concentration.

  7. The positive Indian Ocean Dipole-like response in the tropical Indian Ocean to global warming

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Luo, Yiyong; Lu, Jian; Liu, Fukai

    Climate models project a positive Indian Ocean Dipole (pIOD)-like SST response in the tropical Indian Ocean to global warming. By employing the Community Earth System Model (CESM) and applying an overriding technique to its ocean component Parallel Ocean Program version 2 (POP2), this study investigates the similarity and difference of the formation mechanisms for the changes in the tropical Indian Ocean during the pIOD versus global warming. Results show that their formation processes and related seasonality are quite similar; in particular, the Bjerknes feedback is the leading mechanism in producing the anomalous cooling over the eastern tropics in both cases.more » Some differences are also found, including that the cooling effect of the vertical advection over the eastern tropical Indian Ocean is dominated by the anomalous vertical velocity during the pIOD while it is dominated by the anomalous upper-ocean stratification under global warming. Lastly, these findings above are further examined with an analysis of the mixed layer heat budget.« less

  8. The positive Indian Ocean Dipole-like response in the tropical Indian Ocean to global warming

    DOE PAGES

    Luo, Yiyong; Lu, Jian; Liu, Fukai; ...

    2016-02-04

    Climate models project a positive Indian Ocean Dipole (pIOD)-like SST response in the tropical Indian Ocean to global warming. By employing the Community Earth System Model (CESM) and applying an overriding technique to its ocean component Parallel Ocean Program version 2 (POP2), this study investigates the similarity and difference of the formation mechanisms for the changes in the tropical Indian Ocean during the pIOD versus global warming. Results show that their formation processes and related seasonality are quite similar; in particular, the Bjerknes feedback is the leading mechanism in producing the anomalous cooling over the eastern tropics in both cases.more » Some differences are also found, including that the cooling effect of the vertical advection over the eastern tropical Indian Ocean is dominated by the anomalous vertical velocity during the pIOD while it is dominated by the anomalous upper-ocean stratification under global warming. Lastly, these findings above are further examined with an analysis of the mixed layer heat budget.« less

  9. The study of pinch regimes based on radiation-enhanced compression and anomalous resistivity phenomena and their effects on hard x-ray emission in a Mather type dense plasma focus device (SABALAN2)

    NASA Astrophysics Data System (ADS)

    Piriaei, D.; Mahabadi, T. D.; Javadi, S.; Ghoranneviss, M.; Saw, S. H.; Lee, S.

    2015-12-01

    In this study, by using argon and nitrogen as the filling gases in a Mather type dense plasma focus device at different values of pressure and charging voltage, two different kinds of pinch regimes were observed for each of the gases. The physics of the pinch regimes could be explained by using the two versions of the Lee's computational model which predicted each of the scenarios and clarified their differences between the two gases according to the radiation-enhanced compression and, additionally, predicted the pinch regimes through the anomalous resistivity effect during the pinch time. This was accomplished through the fitting process (simulation) on the current signal. Moreover, the characteristic amplitude and time scales of the anomalous resistances were obtained. The correlations between the features of the plasma current dip and the emitted hard x-ray pulses were observed. The starting time, intensity, duration, and the multiple or single feature of the emitted hard x-ray strongly correlated to the same respective features of the current dip.

  10. An Accident Precursor Analysis Process Tailored for NASA Space Systems

    NASA Technical Reports Server (NTRS)

    Groen, Frank; Stamatelatos, Michael; Dezfuli, Homayoon; Maggio, Gaspare

    2010-01-01

    Accident Precursor Analysis (APA) serves as the bridge between existing risk modeling activities, which are often based on historical or generic failure statistics, and system anomalies, which provide crucial information about the failure mechanisms that are actually operative in the system and which may differ in frequency or type from those in the various models. These discrepancies between the models (perceived risk) and the system (actual risk) provide the leading indication of an underappreciated risk. This paper presents an APA process developed specifically for NASA Earth-to-Orbit space systems. The purpose of the process is to identify and characterize potential sources of system risk as evidenced by anomalous events which, although not necessarily presenting an immediate safety impact, may indicate that an unknown or insufficiently understood risk-significant condition exists in the system. Such anomalous events are considered accident precursors because they signal the potential for severe consequences that may occur in the future, due to causes that are discernible from their occurrence today. Their early identification allows them to be integrated into the overall system risk model used to intbrm decisions relating to safety.

  11. Contemporary Use of Anomalous Diffraction in Biomolecular Structure Analysis.

    PubMed

    Liu, Qun; Hendrickson, Wayne A

    2017-01-01

    The normal elastic X-ray scattering that depends only on electron density can be modulated by an "anomalous" component due to resonance between X-rays and electronic orbitals. Anomalous scattering thereby precisely identifies atomic species, since orbitals distinguish atomic elements, which enables the multi- and single-wavelength anomalous diffraction (MAD and SAD) methods. SAD now predominates in de novo structure determination of biological macromolecules, and we focus here on the prevailing SAD method. We describe the anomalous phasing theory and the periodic table of phasing elements that are available for SAD experiments, differentiating between those readily accessible for at-resonance experiments and those that can be effective away from an edge. We describe procedures for present-day SAD phasing experiments and we discuss optimization of anomalous signals for challenging applications. We also describe methods for using anomalous signals as molecular markers for tracing and element identification. Emerging developments and perspectives are discussed in brief.

  12. The behavioural immune system and the psychology of human sociality.

    PubMed

    Schaller, Mark

    2011-12-12

    Because immunological defence against pathogens is costly and merely reactive, human anti-pathogen defence is also characterized by proactive behavioural mechanisms that inhibit contact with pathogens in the first place. This behavioural immune system comprises psychological processes that infer infection risk from perceptual cues, and that respond to these perceptual cues through the activation of aversive emotions, cognitions and behavioural impulses. These processes are engaged flexibly, producing context-contingent variation in the nature and magnitude of aversive responses. These processes have important implications for human social cognition and social behaviour-including implications for social gregariousness, person perception, intergroup prejudice, mate preferences, sexual behaviour and conformity. Empirical evidence bearing on these many implications is reviewed and discussed. This review also identifies important directions for future research on the human behavioural immune system--including the need for enquiry into underlying mechanisms, additional behavioural consequences and implications for human health and well-being.

  13. Total anomalous systemic with partial anomalous pulmonary venous connections.

    PubMed

    Vallath, Gopakumar; Gajjar, Trushar; Desai, Neelam

    2013-12-01

    A 9-year-old girl with cyanosis, dyspnea, and grade II clubbing was diagnosed by contrast transthoracic echocardiography and angiocardiography to have an anomalous connection of the venae cavae to the physiologic left atrium with partial anomalous pulmonary venous connection. Successful surgical correction was achieved, and the patient's recovery was uneventful.

  14. Areas of Weakly Anomalous to Anomalous Surface Temperature in Chaffee County, Colorado, as Identified from ASTER Thermal Data

    DOE Data Explorer

    Khalid Hussein

    2012-02-01

    Note: This "Weakly Anomalous to Anomalous Surface Temperature" dataset differs from the "Anomalous Surface Temperature" dataset for this county (another remotely sensed CIRES product) by showing areas of modeled temperatures between 1o and 2o above the mean, as opposed to the greater than 2o temperatures contained in the "Anomalous Surface Temperature" dataset. This layer contains areas of anomalous surface temperature in Chaffee County identified from ASTER thermal data and spatial based insolation model. The temperature is calculated using the Emissivity Normalization Algorithm that separate temperature from emissivity. The incoming solar radiation was calculated using spatial based insolation model developed by Fu and Rich (1999). Then the temperature due to solar radiation was calculated using emissivity derived from ASTER data. The residual temperature, i.e. temperature due to solar radiation subtracted from ASTER temperature was used to identify thermally anomalous areas. Areas that had temperature greater than 2o were considered ASTER modeled very warm surface exposures (thermal anomalies). Note: 'o' is used in this description to represent lowercase sigma.

  15. Areas of Weakly Anomalous to Anomalous Surface Temperature in Garfield County, Colorado, as Identified from ASTER Thermal Data

    DOE Data Explorer

    Khalid Hussein

    2012-02-01

    Note: This "Weakly Anomalous to Anomalous Surface Temperature" dataset differs from the "Anomalous Surface Temperature" dataset for this county (another remotely sensed CIRES product) by showing areas of modeled temperatures between 1o and 2o above the mean, as opposed to the greater than 2o temperatures contained in the "Anomalous Surface Temperature" dataset. This layer contains areas of anomalous surface temperature in Garfield County identified from ASTER thermal data and spatial based insolation model. The temperature is calculated using the Emissivity Normalization Algorithm that separate temperature from emissivity. The incoming solar radiation was calculated using spatial based insolation model developed by Fu and Rich (1999). Then the temperature due to solar radiation was calculated using emissivity derived from ASTER data. The residual temperature, i.e. temperature due to solar radiation subtracted from ASTER temperature was used to identify thermally anomalous areas. Areas that had temperature between 1o and 2o were considered ASTER modeled warm surface exposures (thermal anomalies) Note: 'o' is used in this description to represent lowercase sigma.

  16. Areas of Weakly Anomalous to Anomalous Surface Temperature in Routt County, Colorado, as Identified from ASTER Thermal Data

    DOE Data Explorer

    Khalid Hussein

    2012-02-01

    Note: This "Weakly Anomalous to Anomalous Surface Temperature" dataset differs from the "Anomalous Surface Temperature" dataset for this county (another remotely sensed CIRES product) by showing areas of modeled temperatures between 1o and 2o above the mean, as opposed to the greater than 2o temperatures contained in the "Anomalous Surface Temperature" dataset. This layer contains areas of anomalous surface temperature in Routt County identified from ASTER thermal data and spatial based insolation model. The temperature is calculated using the Emissivity Normalization Algorithm that separate temperature from emissivity. The incoming solar radiation was calculated using spatial based insolation model developed by Fu and Rich (1999). Then the temperature due to solar radiation was calculated using emissivity derived from ASTER data. The residual temperature, i.e. temperature due to solar radiation subtracted from ASTER temperature was used to identify thermally anomalous areas. Areas that had temperature between 1o and 2o were considered ASTER modeled warm surface exposures (thermal anomalies). Note: 'o' is used in this description to represent lowercase sigma.

  17. Areas of Weakly Anomalous to Anomalous Surface Temperature in Dolores County, Colorado, as Identified from ASTER Thermal Data

    DOE Data Explorer

    Khalid Hussein

    2012-02-01

    Note: This "Weakly Anomalous to Anomalous Surface Temperature" dataset differs from the "Anomalous Surface Temperature" dataset for this county (another remotely sensed CIRES product) by showing areas of modeled temperatures between 1o and 2o above the mean, as opposed to the greater than 2o temperatures contained in the "Anomalous Surface Temperature" dataset. This layer contains areas of anomalous surface temperature in Dolores County identified from ASTER thermal data and spatial based insolation model. The temperature is calculated using the Emissivity Normalization Algorithm that separate temperature from emissivity. The incoming solar radiation was calculated using spatial based insolation model developed by Fu and Rich (1999). Then the temperature due to solar radiation was calculated using emissivity derived from ASTER data. The residual temperature, i.e. temperature due to solar radiation subtracted from ASTER temperature was used to identify thermally anomalous areas. Areas that had temperature greater than 2o were considered ASTER modeled very warm surface exposures (thermal anomalies) Note: 'o' is used in this description to represent lowercase sigma.

  18. Areas of Weakly Anomalous to Anomalous Surface Temperature in Archuleta County, Colorado, as Identified from ASTER Thermal Data

    DOE Data Explorer

    Khalid Hussein

    2012-02-01

    Note: This "Weakly Anomalous to Anomalous Surface Temperature" dataset differs from the "Anomalous Surface Temperature" dataset for this county (another remotely sensed CIRES product) by showing areas of modeled temperatures between 1o and 2o above the mean, as opposed to the greater than 2o temperatures contained in the "Anomalous Surface Temperature" dataset. This layer contains areas of anomalous surface temperature in Archuleta County identified from ASTER thermal data and spatial based insolation model. The temperature is calculated using the Emissivity Normalization Algorithm that separate temperature from emissivity. The incoming solar radiation was calculated using spatial based insolation model developed by Fu and Rich (1999). Then the temperature due to solar radiation was calculated using emissivity derived from ASTER data. The residual temperature, i.e. temperature due to solar radiation subtracted from ASTER temperature was used to identify thermally anomalous areas. Areas that had temperature between 1o and 2o were considered ASTER modeled warm surface exposures (thermal anomalies). Note: 'o' is used in this description to represent lowercase sigma.

  19. Investigating the predictive validity of implicit and explicit measures of motivation on condom use, physical activity and healthy eating.

    PubMed

    Keatley, David; Clarke, David D; Hagger, Martin S

    2012-01-01

    The literature on health-related behaviours and motivation is replete with research involving explicit processes and their relations with intentions and behaviour. Recently, interest has been focused on the impact of implicit processes and measures on health-related behaviours. Dual-systems models have been proposed to provide a framework for understanding the effects of explicit or deliberative and implicit or impulsive processes on health behaviours. Informed by a dual-systems approach and self-determination theory, the aim of this study was to test the effects of implicit and explicit motivation on three health-related behaviours in a sample of undergraduate students (N = 162). Implicit motives were hypothesised to predict behaviour independent of intentions while explicit motives would be mediated by intentions. Regression analyses indicated that implicit motivation predicted physical activity behaviour only. Across all behaviours, intention mediated the effects of explicit motivational variables from self-determination theory. This study provides limited support for dual-systems models and the role of implicit motivation in the prediction of health-related behaviour. Suggestions for future research into the role of implicit processes in motivation are outlined.

  20. (Multi)fractality of Earthquakes by use of Wavelet Analysis

    NASA Astrophysics Data System (ADS)

    Enescu, B.; Ito, K.; Struzik, Z. R.

    2002-12-01

    The fractal character of earthquakes' occurrence, in time, space or energy, has by now been established beyond doubt and is in agreement with modern models of seismicity. Moreover, the cascade-like generation process of earthquakes -with one "main" shock followed by many aftershocks, having their own aftershocks- may well be described through multifractal analysis, well suited for dealing with such multiplicative processes. The (multi)fractal character of seismicity has been analysed so far by using traditional techniques, like the box-counting and correlation function algorithms. This work introduces a new approach for characterising the multifractal patterns of seismicity. The use of wavelet analysis, in particular of the wavelet transform modulus maxima, to multifractal analysis was pioneered by Arneodo et al. (1991, 1995) and applied successfully in diverse fields, such as the study of turbulence, the DNA sequences or the heart rate dynamics. The wavelets act like a microscope, revealing details about the analysed data at different times and scales. We introduce and perform such an analysis on the occurrence time of earthquakes and show its advantages. In particular, we analyse shallow seismicity, characterised by a high aftershock "productivity", as well as intermediate and deep seismic activity, known for its scarcity of aftershocks. We examine as well declustered (aftershocks removed) versions of seismic catalogues. Our preliminary results show some degree of multifractality for the undeclustered, shallow seismicity. On the other hand, at large scales, we detect a monofractal scaling behaviour, clearly put in evidence for the declustered, shallow seismic activity. Moreover, some of the declustered sequences show a long-range dependent (LRD) behaviour, characterised by a Hurst exponent, H > 0.5, in contrast with the memory-less, Poissonian model. We demonstrate that the LRD is a genuine characteristic and is not an effect of the time series probability distribution function. One of the most attractive features of wavelet analysis is its ability to determine a local Hurst exponent. We show that this feature together with the possibility of extending the analysis to spatial patterns may constitute a valuable approach to search for anomalous (precursory?) patterns of seismic activity.

  1. Malignant Course of Anomalous Left Coronary Artery Causing Sudden Cardiac Arrest: A Case Report and Review of the Literature.

    PubMed

    Anantha Narayanan, Mahesh; DeZorzi, Christopher; Akinapelli, Abhilash; Mahfood Haddad, Toufik; Smer, Aiman; Baskaran, Janani; Biddle, William P

    2015-01-01

    Sudden cardiac arrest has been reported to occur in patients with congenital anomalous coronary artery disease. About 80% of the anomalies are benign and incidental findings at the time of catheterization. We present a case of sudden cardiac arrest caused by anomalous left anterior descending artery. 61-year-old African American female was brought to the emergency department after sudden cardiac arrest. Initial EKG showed sinus rhythm with RBBB and LAFB with nonspecific ST-T wave changes. Coronary angiogram revealed no atherosclerotic disease. The left coronary artery was found to originate from the right coronary cusp. Cardiac CAT scan revealed similar findings with interarterial and intramural course. Patient received one-vessel arterial bypass graft to her anomalous coronary vessel along with a defibrillator for secondary prevention. Sudden cardiac arrest secondary to congenital anomalous coronary artery disease is characterized by insufficient coronary flow by the anomalous left coronary artery to meet elevated left ventricular (LV) myocardial demand. High risk defects include those involved with the proximal coronary artery or coursing of the anomalous artery between the aorta and pulmonary trunk. Per guidelines, our patient received one vessel bypass graft to her anomalous vessel. It is important for clinicians to recognize such presentations of anomalous coronary artery.

  2. Anomalous Extracellular Diffusion in Rat Cerebellum

    PubMed Central

    Xiao, Fanrong; Hrabe, Jan; Hrabetova, Sabina

    2015-01-01

    Extracellular space (ECS) is a major channel transporting biologically active molecules and drugs in the brain. Diffusion-mediated transport of these substances is hindered by the ECS structure but the microscopic basis of this hindrance is not fully understood. One hypothesis proposes that the hindrance originates in large part from the presence of dead-space (DS) microdomains that can transiently retain diffusing molecules. Because previous theoretical and modeling work reported an initial period of anomalous diffusion in similar environments, we expected that brain regions densely populated by DS microdomains would exhibit anomalous extracellular diffusion. Specifically, we targeted granular layers (GL) of rat and turtle cerebella that are populated with large and geometrically complex glomeruli. The integrative optical imaging (IOI) method was employed to evaluate diffusion of fluorophore-labeled dextran (MW 3000) in GL, and the IOI data analysis was adapted to quantify the anomalous diffusion exponent dw from the IOI records. Diffusion was significantly anomalous in rat GL, where dw reached 4.8. In the geometrically simpler turtle GL, dw was elevated but not robustly anomalous (dw = 2.6). The experimental work was complemented by numerical Monte Carlo simulations of anomalous ECS diffusion in several three-dimensional tissue models containing glomeruli-like structures. It demonstrated that both the duration of transiently anomalous diffusion and the anomalous exponent depend on the size of model glomeruli and the degree of their wrapping. In conclusion, we have found anomalous extracellular diffusion in the GL of rat cerebellum. This finding lends support to the DS microdomain hypothesis. Transiently anomalous diffusion also has a profound effect on the spatiotemporal distribution of molecules released into the ECS, especially at diffusion distances on the order of a few cell diameters, speeding up short-range diffusion-mediated signals in less permeable structures. PMID:25954895

  3. Anomalous tidal loading signals in South-West England and Brittany

    NASA Astrophysics Data System (ADS)

    Keshin, M.; Penna, N. T.; Clarke, P. J.; Bos, M. S.; Baker, T. F.

    2010-05-01

    The tidal deformation of the Earth, including ocean tide loading (OTL), sheds light on the Earth's internal structure. Uncertainties in the knowledge of this deformation may be a source of both direct and propagated periodic errors in GPS geodesy. The increasing number of global GPS stations with long histories of observations, as well as recent developments in precise GPS geodesy such as the availability of reprocessed satellite orbits, enables further study of these geophysical and geodetic phenomena. There are more than 10 worldwide regions where OTL displacement amplitudes exceed 25mm. In our work we considered one such region covering South-West England and stretching southward along the coasts of France, Spain and Portugal. Estimates of three-dimensional harmonic site motion at each of the principal diurnal (K1, O1, P1, Q1) and semi-diurnal (K2, M2, N2, S2) frequencies were obtained for 40 European stations with at least 2 year observation span, using the GIPSY-OASIS II software package with reprocessed precise satellite orbits from JPL. All GPS data available from 2002.0 to 2010.0 were considered. 34 stations were situated close to the Atlantic coast; a further 6 inland stations at similar latitudes were processed as a check on solid Earth tide models. Inter-model OTL displacement differences are small, especially for the inland sites; the problematic Bristol Channel area of South-West England was excluded. We validated the quality of our GPS estimates by using and comparing three different analysis strategies: (1) Harmonic estimation of total tidal displacement in 24-hour Precise Point Positioning (PPP) batch solutions: harmonic displacements are estimated per coordinate component for each of the eight principal tidal constituents. OTL is not modelled a priori, and nodal corrections are applied in post-processing after combination of the daily results; (2) Harmonic estimation of residual tidal displacement in 24-hour PPP batch solutions: OTL is modelled a priori using the FES2004 model in the reference frame of the whole Earth system (CM); the residual harmonic displacements are estimated per component per principal tidal constituent. Minor tidal harmonics are removed a priori using the routine "hardisp" by D. Agnew. Because of this, post-processing nodal corrections are not applied; (3) Amplitude and phase from kinematic PPP processing: kinematic GPS processing with a priori OTL modelling using FES2004 and hardisp as in (2); amplitude spectra are later estimated from the entire coordinate time series using the Lomb-Scargle periodogram method. We typically obtain excellent (0.3-0.7mm except for the K1 and K2 constituents) phasor agreement between all three strategies, comparable to the inter-model agreement between computed OTL displacements and suggesting that the GPS analysis strategy robustly detects actual tidal displacements. For sites in inland Europe where computed OTL displacements are less than 10mm with inter-model differences of less than 0.2mm, residual harmonic amplitudes are also at the 0.3-0.7mm level, confirming that solid Earth tides are modelled to at least this accuracy. For GPS stations located in South-West England and Brittany, onshore of the continental shelf, anomalous residual tidal signals were detected of about 2-3mm magnitude for the vertical M2 OTL constituent (10% of the expected signal). In contrast, sites in the Iberian Peninsula, with similar expected OTL magnitudes, have residuals at the expected 0.3-0.7mm level. Sites near to the Bay of Biscay show transitional behaviour between these regimes. Therefore at these locations, the different modern ocean tide models that agree very well must all either be systematically in error, or the difference in behaviour may be caused by errors in the displacement Green's functions applicable to loads on the nearby continental shelf.

  4. Anomalous Accretionary Margin Topography Formed By Repeated Earthquakes

    NASA Astrophysics Data System (ADS)

    Furlong, Kevin P.

    2014-05-01

    It has long been recognized that accretionary margins of major subduction zones undergo substantial deformation. However even with the large amounts of shortening accommodated within the margin, for most subduction zones, there is an extended submarine portion to the accretionary, highly-deformed upper-plate between the trench and the coast. This is a vexing situation since this submarine section typically overlies the actual locked or coupled patch of the plate interface. The result of this is added difficulty in directly observing processes related to the plate interface coupling - such processes as micro-seismicity and the actual patterns of plate coupling. There are a few locations globally in which there are sub-aerially exposed terranes that lie closer to the trench and overlie the inferred coupled or seismogenic portion of the plate interface. Such regions have taken on significance in subduction zone studies as they provide locations to observe the plate interface coupling effects in the near-field. In particular the Pacific coast of Costa Rica provides such a location, and there has been substantial geologic, geophysical, and geodetic research exploiting the positions of these near-trench peninsulas (Nicoya, Osa, and Burica). These sites provide near-field access to plate-interface processes, but whether they represent typical subduction zone behavior remains an open question as the deformational processes or inherited structures that have produced this anomalous topography are not well constrained. Simply put, if the existence of these sub-aerial, near-trench terranes is a result of anomalous behavior on the plate interface (as has been suggested), then their utility in providing high-fidelity near-field insight into the plate interface properties and processes is substantially reduced. Here we propose a new mechanism that could be responsible for the formation of both the Nicoya and Osa Peninsulas in the past, and is currently producing a third peninsula - the Burica Peninsula at the intersection of the Panama fracture zone and the margin. Specifically we propose that the anomalous topography along the Pacific coast of Costa Rica has been produced by repeated, great subduction earthquakes that have ruptured across the boundary separating the Cocos and Nazca plates - the subducted continuation of the Panama fracture zone. The pattern of upper-plate shortening generated by such a process (documented in the 2007 Mw 8.1 Solomon Islands earthquake, which produced co-seismic localized uplift above the subducted transform plate boundary) convolved with the migration history of the Panama triple junction (PTJ) is proposed as the mechanism to produce substantial along-margin, long-lived accretionary margin topography. Specifically we argue that repeated great subduction earthquakes that rupture across fundamental plate boundary structures can produce substantial, long-lived upper plate deformation above the inter-seismically coupled plate interface.

  5. NLO BFKL and Anomalous Dimensions of Light-Ray Operators

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Balitsky, Ian

    2014-01-01

    The anomalous dimensions of light-ray operators of twist two are obtained by analytical continuation of the anomalous dimensions of corresponding local operators. I demonstrate that the asymptotics of these anomalous dimensions at the "BFKL point" j → 1 can be obtained by comparing the light-cone operator expansion with the high-energy expansion in Wilson lines.

  6. Low power generation of equalized broadband CW supercontinua using a novel technique incorporating modulation instability of line broadened pump

    NASA Astrophysics Data System (ADS)

    Prakash, Roopa; Choudhury, Vishal; Arun, S.; Supradeepa, V. R.

    2018-02-01

    Continuous-wave(CW) supercontinuum sources find applications in various domains such as imaging, spectroscopy, test and measurement. They are generated by pumping an optical fiber with a CW laser in the anomalous-dispersion region close to its zero-dispersion wavelength. Modulation instability(MI) sidebands are created, and further broadened and equalized by additional nonlinear processes generating the supercontinuum. This necessitates high optical powers and at lower powers, only MI sidebands can be seen without the formation of the supercontinuum. Obtaining a supercontinuum at low, easily manageable optical powers is attractive for many applications, but current techniques cannot achieve this. In this work, we propose a new mechanism for low power supercontinuum generation utilizing the modified MI gain spectrum for a line-broadened, decorrelated pump. A novel two-stage generation mechanism is demonstrated, where the first stage constituting standard telecom fiber slightly broadens the input pump linewidth. However, this process in the presence of dispersion, acts to de-correlate the different spectral components of the pump signal. When this is sent through highly nonlinear fiber near its zero-dispersion wavelength, the shape of the MI gain spectrum is modified, and this process naturally results in the generation of a broadband, equalized supercontinuum source at much lower powers than possible using conventional single stage spectral broadening. Here, we demonstrate a 0.5W supercontinuum source pumped using a 4W Erbium-Ytterbium co-doped fiber laser with a bandwidth spanning from 1300nm to 2000nm. We also demonstrate an interesting behaviour of this technique of relative insensitivity to the pump wavelength vis-a-vis zero-dispersion wavelength of the fiber.

  7. Anomalous diffusion of Ibuprofen in cyclodextrin nanosponge hydrogels: an HRMAS NMR study

    PubMed Central

    Ferro, Monica; Punta, Carlo; Melone, Lucio; Panzeri, Walter; Rossi, Barbara; Trotta, Francesco

    2014-01-01

    Summary Ibuprofen sodium salt (IP) was encapsulated in cyclodextrin nanosponges (CDNS) obtained by cross-linking of β-cyclodextrin with ethylenediaminetetraacetic acid dianhydride (EDTAn) in two different preparations: CDNSEDTA 1:4 and 1:8, where the 1:n notation indicates the CD to EDTAn molar ratio. The entrapment of IP was achieved by swelling the two polymers with a 0.27 M solution of IP in D2O, leading to colourless, homogeneous hydrogels loaded with IP. The molecular environment and the transport properties of IP in the hydrogels were studied by high resolution magic angle spinning (HRMAS) NMR spectroscopy. The mean square displacement (MSD) of IP in the gels was obtained by a pulsed field gradient spin echo (PGSE) NMR pulse sequence at different observation times t d. The MSD is proportional to the observation time elevated to a scaling factor α. The α values define the normal Gaussian random motion (α = 1), or the anomalous diffusion (α < 1, subdiffusion, α > 1 superdiffusion). The experimental data here reported point out that IP undergoes subdiffusive regime in CDNSEDTA 1:4, while a slightly superdiffusive behaviour is observed in CDNSEDTA 1:8. The transition between the two dynamic regimes is triggered by the polymer structure. CDNSEDTA 1:4 is characterized by a nanoporous structure able to induce confinement effects on IP, thus causing subdiffusive random motion. CDNSEDTA 1:8 is characterized not only by nanopores, but also by dangling EDTA groups ending with ionized COO− groups. The negative potential provided by such groups to the polymer backbone is responsible for the acceleration effects on the IP anion thus leading to the superdiffusive behaviour observed. These results point out that HRMAS NMR spectroscopy is a powerful direct method for the assessment of the transport properties of a drug encapsulated in polymeric scaffolds. The diffusion properties of IP in CDNS can be modulated by suitable polymer synthesis; this finding opens the possibility to design suitable systems for drug delivery with predictable and desired drug release properties. PMID:25550735

  8. Altered Tnnt3 characterizes selective weakness of fast fibers in mice overexpressing FSHD region gene 1 (FRG1)

    PubMed Central

    Sancisi, Valentina; Germinario, Elena; Esposito, Alessandra; Morini, Elisabetta; Peron, Samantha; Moggio, Maurizio; Tomelleri, Giuliano; Danieli-Betto, Daniela

    2013-01-01

    Facioscapulohumeral muscular dystrophy (FSHD), a common hereditary myopathy, is characterized by atrophy and weakness of selective muscle groups. FSHD is considered an autosomal dominant disease with incomplete penetrance and unpredictable variability of clinical expression within families. Mice overexpressing FRG1 (FSHD region gene 1), a candidate gene for this disease, develop a progressive myopathy with features of the human disorder. Here, we show that in FRG1-overexpressing mice, fast muscles, which are the most affected by the dystrophic process, display anomalous fast skeletal troponin T (fTnT) isoform, resulting from the aberrant splicing of the Tnnt3 mRNA that precedes the appearance of dystrophic signs. We determine that muscles of FRG1 mice develop less strength due to impaired contractile properties of fast-twitch fibers associated with an anomalous MyHC-actin ratio and a reduced sensitivity to Ca2+. We demonstrate that the decrease of Ca2+ sensitivity of fast-twitch fibers depends on the anomalous troponin complex and can be rescued by the substitution with the wild-type proteins. Finally, we find that the presence of aberrant splicing isoforms of TNNT3 characterizes dystrophic muscles in FSHD patients. Collectively, our results suggest that anomalous TNNT3 profile correlates with the muscle impairment in both humans and mice. On the basis of these results, we propose that aberrant fTnT represents a biological marker of muscle phenotype severity and disease progression. PMID:24305066

  9. Influence of Westerly Wind Events stochasticity on El Niño amplitude: the case of 2014 vs. 2015

    NASA Astrophysics Data System (ADS)

    Puy, Martin; Vialard, Jérôme; Lengaigne, Matthieu; Guilyardi, Eric; DiNezio, Pedro N.; Voldoire, Aurore; Balmaseda, Magdalena; Madec, Gurvan; Menkes, Christophe; Mcphaden, Michael J.

    2017-10-01

    The weak El Niño of 2014 was preceded by anomalously high equatorial Pacific Warm Water Volume (WWV) and strong Westerly Wind Events (WWEs), which typically lead to record breaking El Nino, like in 1997 and 2015. Here, we use the CNRM-CM5 coupled model to investigate the causes for the stalled El Niño in 2014 and the necessary conditions for extreme El Niños. This model is ideally suited to study this problem because it simulates all the processes thought to be critical for the onset and development of El Niño. It captures El Niño preconditioning by WWV, the WWEs characteristics and their deterministic behaviour in response to warm pool displacements. Our main finding is, that despite their deterministic control, WWEs display a sufficiently strong stochastic component to explain the distinct evolutions of El Niño in 2014 and 2015. A 100-member ensemble simulation initialized with early-spring equatorial conditions analogous to those observed in 2014 and 2015 demonstrates that early-year elevated WWV and strong WWEs preclude the occurrence of a La Niña but lead to El Niños that span the weak (with few WWEs) to extreme (with many WWEs) range. Sensitivity experiments confirm that numerous/strong WWEs shift the El Niño distribution toward larger amplitudes, with a particular emphasis on summer/fall WWEs occurrence which result in a five-fold increase of the odds for an extreme El Niño. A long simulation further demonstrates that sustained WWEs throughout the year and anomalously high WWV are necessary conditions for extreme El Niño to develop. In contrast, we find no systematic influence of easterly wind events (EWEs) on the El Niño amplitude in our model. Our results demonstrate that the weak amplitude of El Niño in 2014 can be explained by WWEs stochastic variations without invoking EWEs or remote influences from outside the tropical Pacific and therefore its peak amplitude was inherently unpredictable at long lead-time.

  10. Magnetic energy storage and conversion in the solar atmosphere

    NASA Technical Reports Server (NTRS)

    Spicer, D. S.; Mariska, J. T.; Boris, J. P.

    1986-01-01

    According to the approach employed in this investigation, particularly important simple configurations of magnetic field and plasma are identified, and it is attempted to achieve an understanding of the large-scale dynamic processes and transformations which these systems can undergo. Fundamental concepts are discussed, taking into account aspects of magnetic energy generation, ideal MHD theory, non-MHD properties, the concept of 'anomalous' resistivity, and global electrodynamic coupling. Questions of magnetically controlled energy conversion are examined, giving attention to magnetic modifications of plasma transport, the transition region structure and flows, channeling and acceleration of plasma, channeling and dissipation of MHD waves, and anomalous dissipation of field-aligned currents. A description of the characteristics of magnetohydrodynamic energy conversion is also provided, and outstanding questions are discussed.

  11. Communication: Probing anomalous diffusion in frequency space

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Stachura, Sławomir; Synchrotron Soleil, L’Orme de Merisiers, 91192 Gif-sur-Yvette; Kneller, Gerald R., E-mail: gerald.kneller@cnrs-orleans.fr

    Anomalous diffusion processes are usually detected by analyzing the time-dependent mean square displacement of the diffusing particles. The latter evolves asymptotically as W(t) ∼ 2D{sub α}t{sup α}, where D{sub α} is the fractional diffusion constant and 0 < α < 2. In this article we show that both D{sub α} and α can also be extracted from the low-frequency Fourier spectrum of the corresponding velocity autocorrelation function. This offers a simple method for the interpretation of quasielastic neutron scattering spectra from complex (bio)molecular systems, in which subdiffusive transport is frequently encountered. The approach is illustrated and validated by analyzing molecularmore » dynamics simulations of molecular diffusion in a lipid POPC bilayer.« less

  12. Endophysical Models Based on Empirical Data

    NASA Astrophysics Data System (ADS)

    Jahn, Robert G.; Dunne, Brenda J.

    2005-10-01

    Any proposed endophysical models need to acknowledge a number of subjective correlates that have been well established in such objectively quantifiable experimental contexts as anomalous human/machine interactions and remote perception information acquisition. Most notable of these factors are conscious and unconscious intention; gender disparities; serial position effects; intrinsic uncertainties; elusive replicability; and emotional resonance between the participants and the devices, process, and tasks. Perhaps even more pertinent are the insensitivities of the anomalous effects to spatial and temporal separations of the participants from the physical targets. Inclusion of subjective coordinates in the models, and exclusion of physical distance and time, raise formidable issues of specification, quantification, and dynamical formulation from both the physical and psychological perspectives. A few primitive examples of possible approaches are presented.

  13. Evidence of W γ γ Production in p p Collisions at s = 8 TeV and Limits on Anomalous Quartic Gauge Couplings with the ATLAS Detector

    DOE PAGES

    Aad, G.; Abbott, B.; Abdallah, J.; ...

    2015-07-16

    Here we report evidence of triple gauge boson production pp→W(ℓν)γγ+X, which is accessible for the first time with the 8 TeV LHC data set. The fiducial cross section for this process is measured in a data sample corresponding to an integrated luminosity of 20.3 fb ₋1, collected by the ATLAS detector in 2012. Events are selected using the W boson decay to eν or μν as well as requiring two isolated photons. The measured cross section is used to set limits on anomalous quartic gauge couplings in the high diphoton mass region.

  14. Effects of turbulence on a kinetic auroral arc model

    NASA Technical Reports Server (NTRS)

    Cornwall, J. M.; Chiu, Y. T.

    1981-01-01

    A plasma kinetic model of an inverted-V auroral arc structure which includes the effects of electrostatic turbulence is proposed. In the absence of turbulence, a parallel potential drop is supported by magnetic mirror forces and charge quasi neutrality, with energetic auroral ions penetrating to low altitudes; relative to the electrons, the ions' pitch angle distribution is skewed toward smaller pitch angles. The electrons energized by the potential drop form a current which excites electrostatic turbulence. In equilibrium the plasma is marginally stable. The conventional anomalous resistivity contribution to the potential drop is very small. Anomalous resistivity processes are far too dissipative to be powered by auroral particles. It is concluded that under certain circumstances equilibrium may be impossible and relaxation oscillations set in.

  15. The enhancement of anomalous Hall effect by inserting MgO layer in perpendicular anisotropic Pd/Co2MnSi/MgO/Pd films

    NASA Astrophysics Data System (ADS)

    Fu, H. R.; Ma, L.; Tian, N.; You, C. Y.; Wang, K.

    2018-05-01

    A systematic study of anomalous Hall effect (AHE) was performed in perpendicular magnetic anisotropic Pd/Co2MnSi(tCMS)/MgO/Pd films. The AHE was significantly intensified by inserting MgO layer, which can be ascribed to the enhancement of spin-orbit coupling and interfacial scattering contribution. Moreover, it was found that the Co and Mn ions were reduced at the interface of Co2MnSi/MgO with annealing process. The stable amount of Mn-O bonding was observed at the Co2MnSi/MgO interface after annealing, implying that the proper Mn-O bonding could be favorable for achieving large AHE.

  16. Beam-return current systems in solar flares

    NASA Technical Reports Server (NTRS)

    Spicer, D. S.; Sudan, R. N.

    1984-01-01

    It is demonstrated that the common assumption made in solar flare beam transport theory that the beam-accompanied return current is purely electrostatically driven is incorrect, and that the return current is both electrostatically and inductively driven, in accordance with Lenz's law, with the inductive effects dominating for times greater than a few plasma periods. In addition, it is shown that a beam can only exist in a solar plasma for a finite time which is much smaller than the inductive return current dissipation time. The importance of accounting for the role of the acceleration mechanism in forming the beam is discussed. In addition, the role of return current driven anomalous resistivity and its subsequent anomalous Joule heating during the flare process is elucidated.

  17. Absorption of Sunlight by Water Vapor in Cloudy Conditions: A Partial Explanation for the Cloud Absorption Anomaly

    NASA Technical Reports Server (NTRS)

    Crisp, D.

    1997-01-01

    The atmospheric radiative transfer algorithms used in most global general circulation models underestimate the globally-averaged solar energy absorbed by cloudy atmospheres by up to 25 W/sq m. The origin of this anomalous absorption is not yet known, but it has been attributed to a variety of sources including oversimplified or missing physical processes in these models, uncertainties in the input data, and even measurement errors. Here, a sophisticated atmospheric radiative transfer model was used to provide a more comprehensive description of the physical processes that contribute to the absorption of solar radiation by the Earth's atmosphere. We found that the amount of sunlight absorbed by a cloudy atmosphere is inversely proportional to the solar zenith angle and the cloud top height, and directly proportional to the cloud optical depth and the water vapor concentration within the clouds. Atmospheres with saturated, optically-thick, low clouds absorbed about 12 W/sq m more than clear atmospheres. This accounts for about 1/2 to 1/3 of the anomalous ab- sorption. Atmospheres with optically thick middle and high clouds usually absorb less than clear atmospheres. Because water vapor is concentrated within and below the cloud tops, this absorber is most effective at small solar zenith angles. An additional absorber that is distributed at or above the cloud tops is needed to produce the amplitude and zenith angle dependence of the observed anomalous absorption.

  18. Assessing the effects of timing irregularities on radio pulsars anomalous braking indices

    NASA Astrophysics Data System (ADS)

    Chukwude, A. E.; Chidi Odo, Finbarr

    2016-10-01

    We investigate the statistical effects of non-discrete timing irregularities on observed radio pulsar braking indices using correlations between the second derivative of the measured anomalous frequency (̈νobs) and some parameters that have been widely used to quantify pulsar timing fluctuations (the timing activity parameter (A), the amount of timing fluctuations absorbed by the cubic term (σR23) and a measure of pulsar rotational stability (σz)) in a large sample of 366 Jodrell Bank Observatory radio pulsars. The result demonstrates that anomalous braking indices are largely artifacts produced by aggregations of fluctuations that occur within or outside the pulsar system. For a subsample of 223 normal radio pulsars whose observed timing activity appeared consistent with instabilities in rotation of the underlying neutron stars (or timing noise) over timescales of ˜ 10 - 40 yr, |̈νobs| strongly correlates (with correlation coefficient |r| ˜ 0.80 - 0.90) with the pulsar timing activity parameters and spin-down properties. On the other hand, no meaningful correlations (r < 0.3) were found between ̈νobs and the timing activity diagnostics and spin-down parameters in the remaining 143 objects, whose timing activity appears significantly dominated by white noise fluctuations. The current result can be better understood if the timing noise in isolated pulsars originates from intrinsic spin-down processes of the underlying neutron stars, but white noise fluctuations largely arise from processes external to the pulsar system.

  19. Anomalous Stars and Where to Find Them

    NASA Astrophysics Data System (ADS)

    Muna, Demitri; Huff, Eric

    2018-01-01

    The sky is now extensively mapped by imaging surveys in wavelengths that span the electromagnetic spectrum, ranging from Fermi and GALEX down to WISE, Planck, and radio surveys like FIRST and VLSS. Individual public catalogs now contain on order hundreds of millions of distinct sources. Recent progress in image analysis techniques makes possible great increases in the efficiency, sensitivity, and reliability of measurements that combine imaging data from multiple probes with heterogeneous properties. This is especially true for the identification of anomalous sources: traditional methods for finding ‘outliers’ typically rely on making hard cuts on noisy catalog properties, greatly restricting the potential discovery space. Cross-catalog matches confine investigation to objects that occur at signal-to-noise ratios sufficient to be independently detectable in a subset of all the available multi-wavelength coverage. The process of merging the latest analyses with existing data is severely hampered, however, by the fractured way in which these data are processed and stored, limitations of data access, the data volume involved, and the computation power required. This has left archive data far from fully exploited. Stellar anomalies present the best place to start: joint distributions of stellar colors and magnitudes have finer structures than extended sources, and modelling of point sources is computationally cheaper than for galaxies. We present a framework to solve the problem of applying new algorithms to old data while overcoming the limitations described above, in the search for the undiscovered anomalous.

  20. Anomalous subdiffusion in fluorescence photobleaching recovery: a Monte Carlo study.

    PubMed Central

    Saxton, M J

    2001-01-01

    Anomalous subdiffusion is hindered diffusion in which the mean-square displacement of a diffusing particle is proportional to some power of time less than one. Anomalous subdiffusion has been observed for a variety of lipids and proteins in the plasma membranes of a variety of cells. Fluorescence photobleaching recovery experiments with anomalous subdiffusion are simulated to see how to analyze the data. It is useful to fit the recovery curve with both the usual recovery equation and the anomalous one, and to judge the goodness of fit on log-log plots. The simulations show that the simplest approximate treatment of anomalous subdiffusion usually gives good results. Three models of anomalous subdiffusion are considered: obstruction, fractional Brownian motion, and the continuous-time random walk. The models differ significantly in their behavior at short times and in their noise level. For obstructed diffusion the approach to the percolation threshold is marked by a large increase in noise, a broadening of the distribution of diffusion coefficients and anomalous subdiffusion exponents, and the expected abrupt decrease in the mobile fraction. The extreme fluctuations in the recovery curves at and near the percolation threshold result from extreme fluctuations in the geometry of the percolation cluster. PMID:11566793

  1. General PFG signal attenuation expressions for anisotropic anomalous diffusion by modified-Bloch equations

    NASA Astrophysics Data System (ADS)

    Lin, Guoxing

    2018-05-01

    Anomalous diffusion exists widely in polymer and biological systems. Pulsed-field gradient (PFG) anomalous diffusion is complicated, especially in the anisotropic case where limited research has been reported. A general PFG signal attenuation expression, including the finite gradient pulse (FGPW) effect for free general anisotropic fractional diffusion { 0 < α , β ≤ 2 } based on the fractional derivative, has not been obtained, where α and β are time and space derivative orders. It is essential to derive a general PFG signal attenuation expression including the FGPW effect for PFG anisotropic anomalous diffusion research. In this paper, two recently developed modified-Bloch equations, the fractal differential modified-Bloch equation and the fractional integral modified-Bloch equation, were extended to obtain general PFG signal attenuation expressions for anisotropic anomalous diffusion. Various cases of PFG anisotropic anomalous diffusion were investigated, including coupled and uncoupled anisotropic anomalous diffusion. The continuous-time random walk (CTRW) simulation was also carried out to support the theoretical results. The theory and the CTRW simulation agree with each other. The obtained signal attenuation expressions and the three-dimensional fractional modified-Bloch equations are important for analyzing PFG anisotropic anomalous diffusion in NMR and MRI.

  2. Long-wavelength macromolecular crystallography - First successful native SAD experiment close to the sulfur edge

    NASA Astrophysics Data System (ADS)

    Aurelius, O.; Duman, R.; El Omari, K.; Mykhaylyk, V.; Wagner, A.

    2017-11-01

    Phasing of novel macromolecular crystal structures has been challenging since the start of structural biology. Making use of anomalous diffraction of natively present elements, such as sulfur and phosphorus, for phasing has been possible for some systems, but hindered by the necessity to access longer X-ray wavelengths in order to make most use of the anomalous scattering contributions of these elements. Presented here are the results from a first successful experimental phasing study of a macromolecular crystal structure at a wavelength close to the sulfur K edge. This has been made possible by the in-vacuum setup and the long-wavelength optimised experimental setup at the I23 beamline at Diamond Light Source. In these early commissioning experiments only standard data collection and processing procedures have been applied, in particular no dedicated absorption correction has been used. Nevertheless the success of the experiment demonstrates that the capability to extract phase information can be even further improved once data collection protocols and data processing have been optimised.

  3. Contemporary Use of Anomalous Diffraction in Biomolecular Structure Analysis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liu Q.; Hendrickson, W.

    2017-01-01

    The normal elastic X-ray scattering that depends only on electron density can be modulated by an ?anomalous? component due to resonance between X-rays and electronic orbitals. Anomalous scattering thereby precisely identifies atomic species, since orbitals distinguish atomic elements, which enables the multi- and single-wavelength anomalous diffraction (MAD and SAD) methods. SAD now predominates in de novo structure determination of biological macromolecules, and we focus here on the prevailing SAD method. We describe the anomalous phasing theory and the periodic table of phasing elements that are available for SAD experiments, differentiating between those readily accessible for at-resonance experiments and those thatmore » can be effective away from an edge. We describe procedures for present-day SAD phasing experiments and we discuss optimization of anomalous signals for challenging applications. We also describe methods for using anomalous signals as molecular markers for tracing and element identification. Emerging developments and perspectives are discussed in brief.« less

  4. Anomalous dual drainage of the right pulmonary veins in a patient with cor triatriatum: report of a case without scimitar sign.

    PubMed

    Tansel, T; Harmandar, B; Dayioglu, E; Onursal, E

    2006-02-01

    The majority of patients with partial anomalous drainage of pulmonary veins are asymptomatic during infancy and childhood. Patients with significant left-to-right shunt develop symptoms and benefit from early corrective surgery. Anomalous pulmonary veins draining into inferior vena cava is very rare and frequently encountered in association with scimitar syndrome. The purpose of this case report is to describe a non-scimitar patient with cor triatriatum who had anomalous dual drainage of right pulmonary veins into inferior vena cava/left atrium and anomalous connection of persistent left superior vena cava with a common pulmonary venous chamber. The patient underwent an operation with redirection of anomalous pulmonary venous drainage into left atrium and ligation of persistent left superior vena cava.

  5. The behavioural immune system and the psychology of human sociality

    PubMed Central

    Schaller, Mark

    2011-01-01

    Because immunological defence against pathogens is costly and merely reactive, human anti-pathogen defence is also characterized by proactive behavioural mechanisms that inhibit contact with pathogens in the first place. This behavioural immune system comprises psychological processes that infer infection risk from perceptual cues, and that respond to these perceptual cues through the activation of aversive emotions, cognitions and behavioural impulses. These processes are engaged flexibly, producing context–contingent variation in the nature and magnitude of aversive responses. These processes have important implications for human social cognition and social behaviour—including implications for social gregariousness, person perception, intergroup prejudice, mate preferences, sexual behaviour and conformity. Empirical evidence bearing on these many implications is reviewed and discussed. This review also identifies important directions for future research on the human behavioural immune system—including the need for enquiry into underlying mechanisms, additional behavioural consequences and implications for human health and well-being. PMID:22042918

  6. Anomalous Lead Isotopic Composition of Galena and Age of Altered Uranium Minerals: a Case study of Chauli Deposits, Chatkal-Qurama District, Uzbekistan

    NASA Astrophysics Data System (ADS)

    Chernyshev, I. V.; Golubev, V. N.; Chugaev, A. V.

    2017-11-01

    The enrichment of lead isotopic composition of nonuranium minerals, in the first place galena in 206Pb and 207Pb, as compared to common lead is a remarkable feature of uranium deposits. The study of such lead isotopic composition anomalous in 206Pb and 207Pb in uranium minerals provides an opportunity for not only identification of superimposed processes resulting in transformation of uranium ores during deposit history but also calculation of age of these processes under certain model assumptions. Galena from the Chauli deposit in the Chatkal-Qurama district, Uzbekistan, a typical representative of hydrothermal uranium deposits associated with domains of Phanerozoic continental volcanism, has been examined with the highprecision (±0.02%) MC-ICP-MS method. Twenty microsamples of galena were taken from polished sections. Six of them are galena hosted in carbonate adjacent to pitchblende spherulites or filling thin veinlets (approximately 60 μm) cutting pitchblende. Isotopically anomalous lead with 206Pb/204Pb and 207Pb/204Pb values reaching 20.462 and 15.743, respectively, has been found in these six microsamples in contrast to another fourteen in which the Pb-Pb characteristics are consistent with common lead. On the basis of these data and with account for the 292 ± 2 Ma age for the Chauli deposit, the age of epigenetic transformation of uranium ores of this deposit has been estimated. During this process, radiogenic lead partly lost from pitchblende was captured into galena. The obtained date is 170 Ma. In the Chatkal-Qurama district, these epigenetic processes are apparently caused by the interaction of uranium minerals with activated underground water under tectonic activity and relief transformation, which took place from the post-Permian (i.e., after the Chauli formation) to the Jurassic period.

  7. Ethnographic methods for process evaluations of complex health behaviour interventions.

    PubMed

    Morgan-Trimmer, Sarah; Wood, Fiona

    2016-05-04

    This article outlines the contribution that ethnography could make to process evaluations for trials of complex health-behaviour interventions. Process evaluations are increasingly used to examine how health-behaviour interventions operate to produce outcomes and often employ qualitative methods to do this. Ethnography shares commonalities with the qualitative methods currently used in health-behaviour evaluations but has a distinctive approach over and above these methods. It is an overlooked methodology in trials of complex health-behaviour interventions that has much to contribute to the understanding of how interventions work. These benefits are discussed here with respect to three strengths of ethnographic methodology: (1) producing valid data, (2) understanding data within social contexts, and (3) building theory productively. The limitations of ethnography within the context of process evaluations are also discussed.

  8. Thoracoscopic Surgery for Partial Anomalous Pulmonary Venous Connection with Dual Drainage.

    PubMed

    Fuchigami, Tai; Gabe, Atsushi; Takahashi, Kazuhiro; Nishioka, Masahiko; Akashige, Toru; Nagata, Nobuhiro

    2015-10-01

    We report our technique for thoracoscopic surgery for a 15-year-old female (body weight, 59 kg) diagnosed with partial anomalous pulmonary venous connection with dual drainage. A large anomalous right lower pulmonary vein (RLPV) was drained into the inferior vena cava and left atrium, along with thoracoscopic ligation and clipping of RLPV and some anomalous hepatic veins. © 2015 Wiley Periodicals, Inc.

  9. Anomalous extracellular diffusion in rat cerebellum.

    PubMed

    Xiao, Fanrong; Hrabe, Jan; Hrabetova, Sabina

    2015-05-05

    Extracellular space (ECS) is a major channel transporting biologically active molecules and drugs in the brain. Diffusion-mediated transport of these substances is hindered by the ECS structure but the microscopic basis of this hindrance is not fully understood. One hypothesis proposes that the hindrance originates in large part from the presence of dead-space (DS) microdomains that can transiently retain diffusing molecules. Because previous theoretical and modeling work reported an initial period of anomalous diffusion in similar environments, we expected that brain regions densely populated by DS microdomains would exhibit anomalous extracellular diffusion. Specifically, we targeted granular layers (GL) of rat and turtle cerebella that are populated with large and geometrically complex glomeruli. The integrative optical imaging (IOI) method was employed to evaluate diffusion of fluorophore-labeled dextran (MW 3000) in GL, and the IOI data analysis was adapted to quantify the anomalous diffusion exponent dw from the IOI records. Diffusion was significantly anomalous in rat GL, where dw reached 4.8. In the geometrically simpler turtle GL, dw was elevated but not robustly anomalous (dw = 2.6). The experimental work was complemented by numerical Monte Carlo simulations of anomalous ECS diffusion in several three-dimensional tissue models containing glomeruli-like structures. It demonstrated that both the duration of transiently anomalous diffusion and the anomalous exponent depend on the size of model glomeruli and the degree of their wrapping. In conclusion, we have found anomalous extracellular diffusion in the GL of rat cerebellum. This finding lends support to the DS microdomain hypothesis. Transiently anomalous diffusion also has a profound effect on the spatiotemporal distribution of molecules released into the ECS, especially at diffusion distances on the order of a few cell diameters, speeding up short-range diffusion-mediated signals in less permeable structures. Copyright © 2015 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  10. Low temperature magnetization and anomalous high temperature dielectric behaviour of (1-x) YMnO3/xZnFe2O4 composites

    NASA Astrophysics Data System (ADS)

    Kumar, Virendra; Gaur, Anurag

    2018-04-01

    We synthesized YMnO3 and ZnFe2O4 composites, (1-x)YMnO3/x(ZnFe2O4) with x = 0, 0.05, 0.10, and 0.15 by high temperature sintering. X-ray diffraction (XRD) patterns indicate the successful formation of composites. Weak ferromagnetism is manifested below Néel temperature (TN) for pristine YMnO3, according to (M-H) study performed at 10 K. For (1-x)YMnO3/xZnFe2O4 (x = 0.05, 0.10, 0.15) a thin coercivity is observed in all compositions, due to short range magnetic ordering at low temperature after the insertion of ZnFe2O4. For pristine YMnO3 explicit divarication between FC-ZFC curves is observed, with crimps observed in both FC and ZFC curves at 75 K, which is the TN of YMnO3. For 1-x(YMnO3)/x ZnFe2O4 composites (x = 0.05, 0.10, 0.15) crimps are perceived only in ZFC curves at slightly varying values of 39.8, 42.32 and 45.63 K respectively. Anomalous peaks are observed in high temperature dielectric curves above 400 K for 1-x(YMnO3)/xZnFe2O4 (x = 0, 0.05, 0.10, 0.15) composites due to Maxwell-Wagner relaxation effect.

  11. Anomalous Light Phenomena vs. Bioelectric Brain Activity

    NASA Astrophysics Data System (ADS)

    Teodorani, M.; Nobili, G.

    We present a research proposal concerning the instrumented investigation of anomalous light phenomena that are apparently correlated with particular mind states, such as prayer, meditation or psi. Previous research by these authors demonstrate that such light phenomena can be monitored and measured quite efficiently in areas of the world where they are reported in a recurrent way. Instruments such as optical equipment for photography and spectroscopy, VLF spectrometers, magnetometers, radar and IR viewers were deployed and used massively in several areas of the world. Results allowed us to develop physical models concerning the structural and time-variable behaviour of light phenomena, and their kinematics. Recent insights and witnesses have suggested to us that a sort of "synchronous connection" seems to exist between plasma-like phenomena and particular mind states of experiencers who seem to trigger a light manifestation which is very similar to the one previously investigated. The main goal of these authors is now aimed at the search for a concrete "entanglement-like effect" between the experiencer's mind and the light phenomena, in such a way that both aspects are intended to be monitored and measured simultaneously using appropriate instrumentation. The goal of this research project is twofold: a) to verify quantitatively the existence of one very particular kind of mind-matter interaction and to study in real time its physical and biophysical manifestations; b) to repeat the same kind of experiment using the same test-subject in different locations and under various conditions of geomagnetic activity.

  12. Decision analysis to define the optimal management of athletes with anomalous aortic origin of a coronary artery.

    PubMed

    Mery, Carlos M; Lopez, Keila N; Molossi, Silvana; Sexson-Tejtel, S Kristen; Krishnamurthy, Rajesh; McKenzie, E Dean; Fraser, Charles D; Cantor, Scott B

    2016-11-01

    The goal of this study was to use decision analysis to evaluate the impact of varying uncertainties on the outcomes of patients with anomalous aortic origin of a coronary artery. Two separate decision analysis models were created: one for anomalous left coronary artery (ALCA) and one for anomalous right coronary artery (ARCA). Three strategies were compared: observation, exercise restriction, and surgery. Probabilities and health utilities were estimated on the basis of existing literature. Deterministic and probabilistic sensitivity analyses were performed. Surgery was the optimal management strategy for patients <30 years of age with ALCA. As age increased, observation became an equivalent strategy and eventually surpassed surgery as the treatment of choice. The advantage on life expectancy for surgery over observation ranged from 2.6 ± 1.7 years for a 10-year-old patient to -0.03 ± 0.1 for a 65-year old patient. In patients with ARCA, observation was the optimal strategy for most patients with a life expectancy advantage over surgery of 0.1 ± 0.1 years to 0.2 ± 0.4 years, depending on age. Surgery was the preferred strategy only for patients <25 years of age when the perceived risk of sudden cardiac death was high and the perioperative mortality was low. Exercise restriction was a suboptimal strategy for both ALCA and ARCA in all scenarios. The optimal management in anomalous aortic origin of a coronary artery depends on multiple factors, including individual patient characteristics. Decision analysis provides a tool to understand how these characteristics affect the outcomes with each management strategy and thus may aid in the decision making process for a particular patient. Copyright © 2016 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

  13. Magnetospheric disturbance effects on the Equatorial Ionization Anomaly (EIA) : an overview

    NASA Astrophysics Data System (ADS)

    Abdu, M. A.; Sobral, J. H. A.; de Paula, E. R.; Batista, I. S.

    1992-12-01

    The Equatorial lonization Anomaly (EIA) development can undergo drastic modification in the form of an anomalous occurrence at local times outside that of its quiet time development and/or inhibition/enhancement at local times of its normal occurrences. This happens for disturbed electrodynamic conditions of the global ionosphere-thermosphere-magnetosphere system, consequent upon the triggering of a magnetospheric storm event. Direct penetration to equatorial latitudes of the magnetospheric electric fields and the thermospheric disturbances involving winds, electric fields and composition changes produce significant alteration in the EIA morphology and dynamics. Results on statistical behaviour based on accumulated ground-based data sets, and those from recent theoretical modelling efforts and from satellite and ground-based observations, are reviewed. Some outstanding problems of the EIA response to magnetospheric disturbances that deserve attention in the coming years are pointed out.

  14. Hidden negative linear compressibility in lithium l-tartrate.

    PubMed

    Yeung, Hamish H-M; Kilmurray, Rebecca; Hobday, Claire L; McKellar, Scott C; Cheetham, Anthony K; Allan, David R; Moggach, Stephen A

    2017-02-01

    By decoupling the mechanical behaviour of building units for the first time in a wine-rack framework containing two different strut types, we show that lithium l-tartrate exhibits NLC with a maximum value, K max = -21 TPa -1 , and an overall NLC capacity, χ NLC = 5.1%, that are comparable to the most exceptional materials to date. Furthermore, the contributions from molecular strut compression and angle opening interplay to give rise to so-called "hidden" negative linear compressibility, in which NLC is absent at ambient pressure, switched on at 2 GPa and sustained up to the limit of our experiment, 5.5 GPa. Analysis of the changes in crystal structure using variable-pressure synchrotron X-ray diffraction reveals new chemical and geometrical design rules to assist the discovery of other materials with exciting hidden anomalous mechanical properties.

  15. The refractive index and electronic gap of water and ice increase with increasing pressure

    PubMed Central

    Pan, Ding; Wan, Quan; Galli, Giulia

    2014-01-01

    Determining the electronic and dielectric properties of water at high pressure and temperature is an essential prerequisite to understand the physical and chemical properties of aqueous environments under supercritical conditions, for example, in the Earth interior. However, optical measurements of compressed ice and water remain challenging, and it has been common practice to assume that their band gap is inversely correlated with the measured refractive index, consistent with observations reported for hundreds of materials. Here we report ab initio molecular dynamics and electronic structure calculations showing that both the refractive index and the electronic gap of water and ice increase with increasing pressure, at least up to 30 GPa. Subtle electronic effects, related to the nature of interband transitions and band edge localization under pressure, are responsible for this apparently anomalous behaviour. PMID:24861665

  16. Theoretical analyses of resonant frequency shift in anomalous dispersion enhanced resonant optical gyroscopes.

    PubMed

    Lin, Jian; Liu, Jiaming; Zhang, Hao; Li, Wenxiu; Zhao, Lu; Jin, Junjie; Huang, Anping; Zhang, Xiaofu; Xiao, Zhisong

    2016-12-12

    Rigorous expressions of resonant frequency shift (RFS) in anomalous dispersion enhanced resonant optical gyroscopes (ADEROGs) are deduced without making approximation, which provides a precise theoretical guidance to achieve ultra-sensitive ADEROGs. A refractive index related modification factor is introduced when considering special theory of relativity (STR). We demonstrate that the RFS will not be "infinitely large" by using critical anomalous dispersion (CAD) and negative modification does not exist, which make the mechanism of anomalous dispersion enhancement clear and coherent. Although step change of RFS will happen when the anomalous dispersion condition varies, the amplification of RFS is limited by attainable variation of refractive index in practice. Moreover, it is shown that the properties of anomalous dispersion will influence not only the amplification of RFS, but also the detection range of ADEROGs.

  17. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hegde, Raghurama P.; Fedorov, Alexander A.; Sauder, J. Michael

    Single-wavelength anomalous dispersion (SAD) utilizing anomalous signal from native S atoms, or other atoms withZ≤ 20, generally requires highly redundant data collected using relatively long-wavelength X-rays. Here, the results from two proteins are presented where the anomalous signal from serendipitously acquired surface-bound Ca atoms with an anomalous data multiplicity of around 10 was utilized to drivede novostructure determination. In both cases, the Ca atoms were acquired from the crystallization solution, and the data-collection strategy was not optimized to exploit the anomalous signal from these scatterers. The X-ray data were collected at 0.98 Å wavelength in one case and at 1.74more » Å in the other (the wavelength was optimized for sulfur, but the anomalous signal from calcium was exploited for structure solution). Similarly, using a test case, it is shown that data collected at ~1.0 Å wavelength, where thef'' value for sulfur is 0.28 e, are sufficient for structure determination using intrinsic S atoms from a strongly diffracting crystal. Interestingly, it was also observed thatSHELXDwas capable of generating a substructure solution from high-exposure data with a completeness of 70% for low-resolution reflections extending to 3.5 Å resolution with relatively low anomalous multiplicity. Considering the fact that many crystallization conditions contain anomalous scatterers such as Cl, Ca, Mnetc., checking for the presence of fortuitous anomalous signal in data from well diffracting crystals could prove useful in either determining the structurede novoor in accurately assigning surface-bound atoms.« less

  18. Influence of ore processing activity on Hg, As and Sb contamination and fractionation in soils in a former mining site of Monte Amiata ore district (Italy).

    PubMed

    Protano, Giuseppe; Nannoni, Francesco

    2018-05-01

    A geochemical study was carried out at the former Abbadia San Salvatore (ASS) mining site of the Monte Amiata ore district (Italy). Hg, As and Sb total contents and fractionation using a sequential extraction procedure were determined in soil and mining waste samples. Ore processing activities provided a different contribution to Hg contamination and concentration in soil fractions, influencing its behaviour as volatility and availability. Soils of roasting zone showed the highest Hg contamination levels mainly due to the deposition of Hg released as Hg 0 by furnaces during cinnabar roasting. High Hg contents were also measured in waste from the lower part of mining dump due to the presence of cinnabar. The fractionation pattern suggested that Hg was largely as volatile species in both uncontaminated and contaminated soils and mining waste, and concentrations of these Hg species increased as contamination increased. These findings were in agreement with the fact that the ASS mining site is characterized by high Hg concentrations in the air and the presence of Hg 0 liquid droplets in soil. Volatile Hg species were also prevalent in uncontaminated soils likely because the Monte Amiata region is an area characterized by anomalous fluxes of gaseous Hg from natural and anthropogenic inputs. At the ASS mining site soils were also contaminated by Sb, while As contents were comparable with its local background in soil. In all soil and waste samples Sb and As were preferentially in residual fraction. Copyright © 2018 Elsevier Ltd. All rights reserved.

  19. The Extended Theory of Planned Behaviour and College Grades: The Role of Cognition and Past Behaviour in the Prediction of Students' Academic Intentions and Achievements

    ERIC Educational Resources Information Center

    Kovac, Velibor Bobo; Cameron, David Lansing; Høigaard, Rune

    2016-01-01

    Understanding the underlying processes influencing college students' academic achievement represents an important goal of educational research. The aim of the present study was to examine the utility of the extended Theory of Planned Behaviour (TPB) and the relative influence of cognitive processes and measures of past behaviour in the prediction…

  20. Background and Recent Progress in Anomalous Transport Simulation

    DTIC Science & Technology

    2017-07-19

    NUMBER (Include area code) 19 July 2017 Briefing Charts 14 June 2017 - 19 July 2017 Background and Recent Progress in Anomalous Transport Simulation ...and Recent Progress in Anomalous Transport Simulation 19 Jul 2017 Justin Koo AFRL/RQRS Edwards AFB, CA 2DISTRIBUTION A: Approved for public release...Baalrud, S.D. and Chabert, P., “Theory for the anomalous electron transport in Hall effect thrusters. I. Insights from particle-in-cell simulations

  1. An alternative theoretical model for an anomalous hollow beam.

    PubMed

    Cai, Yangjian; Wang, Zhaoying; Lin, Qiang

    2008-09-15

    An alternative and convenient theoretical model is proposed to describe a flexible anomalous hollow beam of elliptical symmetry with an elliptical solid core, which was observed in experiment recently (Phys. Rev. Lett, 94 (2005) 134802). In this model, the electric field of anomalous hollow beam is expressed as a finite sum of elliptical Gaussian modes. Flattopped beams, dark hollow beams and Gaussian beams are special cases of our model. Analytical propagation formulae for coherent and partially coherent anomalous hollow beams passing through astigmatic ABCD optical systems are derived. Some numerical examples are calculated to show the propagation and focusing properties of coherent and partially coherent anomalous hollow beams.

  2. Effects of strong earthquakes in variations of electrical and meteorological parameters of the near-surface atmosphere in Kamchatka region

    NASA Astrophysics Data System (ADS)

    Smirnov, S. E.; Mikhailova, G. A.; Mikhailov, Yu. M.; Kapustina, O. V.

    2017-09-01

    The diurnal variations in electrical (quasistatic electric field and electrical conductivity) and meteorological (temperature, pressure, relative humidity of the atmosphere, and wind speed) parameters, measured simultaneously before strong earthquakes in Kamchatka region (November 15, 2006, M = 8.3; January 13, 2007, M = 8.1; January 30, 2016, M = 7.2), are studied for the first time in detail. It is found that a successively anomalous increase in temperature, despite the negative regular trend in these winter months, was observed in the period of six-seven days before the occurrences of earthquakes. An anomalous temperature increase led to the formation of "winter thunderstorm" conditions in the near-surface atmosphere of Kamchatka region, which was manifested in the appearance of an anomalous, type 2 electrical signal, the amplification of and intensive variations in electrical conductivity, heavy precipitation (snow showers), high relative humidity of air, storm winds, and pressure changes. With the weak flow of natural heat radiation in this season, the observed dynamics of electric and meteorological processes can likely be explained by the appearance of an additional heat source of seismic nature.

  3. Single top quark photoproduction at the LHC

    NASA Astrophysics Data System (ADS)

    de Favereau de Jeneret, J.; Ovyn, S.

    2008-08-01

    High-energy photon-proton interactions at the LHC offer interesting possibilities for the study of the electroweak sector up to TeV scale and searches for processes beyond the Standard Model. An analysis of the W associated single top photoproduction has been performed using the adapted MadGraph/MadEvent [F. Maltoni and T. Stelzer, JHEP 0302, (2003) 027; T. Stelzer and W.F. Long, Phys. Commun. 81, (1994) 357-371] and CalcHEP [A. Pukhov, Nucl. Inst. Meth A 502, (2003) 596-598] programs interfaced to the Pythia [T. Sjöstrand et al., Comput. Phys. Commun. 135, (2001) 238] generator and a fast detector simulation program. Event selection and suppression of main backgrounds have been studied. A comparable sensitivity to |V| to those obtained using the standard single top production in pp collisions has been achieved already for 10 fb of integrated luminosity. Photoproduction at the LHC provides also an attractive framework for observation of the anomalous production of single top due to Flavour-Changing Neutral Currents. The sensitivity to anomalous coupling parameters, k and k is presented and indicates that stronger limits can be placed on anomalous couplings after 1 fb.

  4. Reduced North American terrestrial primary productivity linked to anomalous Arctic warming

    DOE PAGES

    Kim, Jin-Soo; Kug, Jong-Seong; Jeong, Su-Jong; ...

    2017-07-10

    Warming temperatures in the Northern Hemisphere have enhanced terrestrial productivity. Despite the warming trend, North America has experienced more frequent and more intense cold weather events during winters and springs. These events have been linked to anomalous Arctic warming since 1990, and may affect terrestrial processes. Here we analyse many observation data sets and numerical model simulations to evaluate links between Arctic temperatures and primary productivity in North America. We find that positive springtime temperature anomalies in the Arctic have led to negative anomalies in gross primary productivity over most of North America during the last three decades, which amountmore » to a net productivity decline of 0.31 PgC yr -1 across the continent. This decline is mainly explained by two factors: severe cold conditions in northern North America and lower precipitation in the South Central United States. In addition, United States crop-yield data reveal that during years experiencing anomalous warming in the Arctic, yields declined by approximately 1 to 4% on average, with individual states experiencing declines of up to 20%. We conclude that the strengthening of Arctic warming anomalies in the past decades has remotely reduced productivity over North America.« less

  5. Delusions as performance failures.

    PubMed

    Gerrans, P

    2001-08-01

    Delusions are explanations of anomalous experiences. A theory of delusion requires an explanation of both the anomalous experience and the apparently irrational explanation generated by the delusional subject. Hence, we require a model of rational belief formation against which the belief formation of delusional subjects can be evaluated. I first describe such a model, distinguishing procedural from pragmatic rationality. Procedural rationality is the use of rules or procedures, deductive or inductive, that produce an inferentially coherent set of propositions. Pragmatic rationality is the use of procedural rationality in context. I then apply the distinction to the explanation of the Capgras and the Cotard delusions. I then argue that delusions are failures of pragmatic rationality. I examine the nature of these failures employing the distinction between performance and competence familiar from Chomskian linguistics. This approach to the irrationality of delusions reconciles accounts in which the explanation of the anomalous experience exhausts the explanation of delusion, accounts that appeal to further deficits within the reasoning processes of delusional subjects, and accounts that argue that delusions are not beliefs at all. (Respectively, one-stage, two-stage, and expressive accounts.) In paradigm cases that concern cognitive neuropsychiatry the irrationality of delusional subjects should be thought of as a performance deficit in pragmatic rationality.

  6. Studies of multi-ion-fluid yield anomaly in shock-driven implosions

    NASA Astrophysics Data System (ADS)

    Rinderknecht, H. G.; Rosenberg, M. J.; Li, C. K.; Zylstra, A. B.; Sio, H.; Gatu Johnson, M.; Frenje, J. A.; Séguin, F. H.; Petrasso, R. D.; Amendt, P. A.; Bellei, C.; Wilks, S. C.; Zimmerman, G.; Hoffman, N. M.; Kagan, G.; Molvig, K.; Glebov, V. Yu.; Stoeckl, C.; Marshall, F. J.; Seka, W.; Delettrez, J. A.; Sangster, T. C.; Betti, R.; Goncharov, V. N.; Meyerhofer, D. D.

    2014-10-01

    A. NIKROO, GA - Anomalously reduced yields relative to hydrodynamically calculated values have been observed for mixtures of D:3He compared to pure D2 gas-filled implosions in a series of shock-driven implosions at OMEGA. An extensive suite of measurements including temporal and spatial measurements of both the DD- and D3He-fusion reactions were obtained to identify the origin and physics behind this anomalous yield reduction. Measured spectral linewidths of fusion products suggest that the D ions are not thermalized to 3He during the burn, contributing to the reduced yield. The hypothesis that ion-species separation due to diffusive processes contributes to the observed yield reduction is explored using hydrodynamic simulations incorporating ion diffusion. Recent observations by Rosenberg et al. of a yield reduction with increased ion-ion mean free path do not explain the observed anomalous yield trend. Future work that will directly probe species separation with high-precision relative fusion reaction rate measurements between DD-neutrons and D3He-protons using the DualPTD instrument is discussed. This work was supported in part by the U.S. DOE, NLUF, LLE, and LLNL.

  7. Onset of anomalous diffusion from local motion rules

    NASA Astrophysics Data System (ADS)

    de Nigris, Sarah; Carletti, Timoteo; Lambiotte, Renaud

    2017-02-01

    Anomalous diffusion processes, in particular superdiffusive ones, are known to be efficient strategies for searching and navigation in animals and also in human mobility. One way to create such regimes are Lévy flights, where the walkers are allowed to perform jumps, the "flights," that can eventually be very long as their length distribution is asymptotically power-law distributed. In our work, we present a model in which walkers are allowed to perform, on a one-dimensional lattice, "cascades" of n unitary steps instead of one jump of a randomly generated length, as in the Lévy case, where n is drawn from a cascade distribution pn. We show that this local mechanism may give rise to superdiffusion or normal diffusion when pn is distributed as a power law. We also introduce waiting times that are power-law distributed as well and therefore the probability distribution scaling is steered by the two local distributions power-law exponents. As a perspective, our approach may engender a possible generalization of anomalous diffusion in context where distances are difficult to define, as in the case of complex networks, and also provide an interesting model for diffusion in temporal networks.

  8. Reduced North American terrestrial primary productivity linked to anomalous Arctic warming

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kim, Jin-Soo; Kug, Jong-Seong; Jeong, Su-Jong

    Warming temperatures in the Northern Hemisphere have enhanced terrestrial productivity. Despite the warming trend, North America has experienced more frequent and more intense cold weather events during winters and springs. These events have been linked to anomalous Arctic warming since 1990, and may affect terrestrial processes. Here we analyse many observation data sets and numerical model simulations to evaluate links between Arctic temperatures and primary productivity in North America. We find that positive springtime temperature anomalies in the Arctic have led to negative anomalies in gross primary productivity over most of North America during the last three decades, which amountmore » to a net productivity decline of 0.31 PgC yr -1 across the continent. This decline is mainly explained by two factors: severe cold conditions in northern North America and lower precipitation in the South Central United States. In addition, United States crop-yield data reveal that during years experiencing anomalous warming in the Arctic, yields declined by approximately 1 to 4% on average, with individual states experiencing declines of up to 20%. We conclude that the strengthening of Arctic warming anomalies in the past decades has remotely reduced productivity over North America.« less

  9. The study of pinch regimes based on radiation-enhanced compression and anomalous resistivity phenomena and their effects on hard x-ray emission in a Mather type dense plasma focus device (SABALAN2)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Piriaei, D.; Javadi, S.; Ghoranneviss, M.

    In this study, by using argon and nitrogen as the filling gases in a Mather type dense plasma focus device at different values of pressure and charging voltage, two different kinds of pinch regimes were observed for each of the gases. The physics of the pinch regimes could be explained by using the two versions of the Lee's computational model which predicted each of the scenarios and clarified their differences between the two gases according to the radiation-enhanced compression and, additionally, predicted the pinch regimes through the anomalous resistivity effect during the pinch time. This was accomplished through the fittingmore » process (simulation) on the current signal. Moreover, the characteristic amplitude and time scales of the anomalous resistances were obtained. The correlations between the features of the plasma current dip and the emitted hard x-ray pulses were observed. The starting time, intensity, duration, and the multiple or single feature of the emitted hard x-ray strongly correlated to the same respective features of the current dip.« less

  10. Probing anomalous W W γ triple gauge bosons coupling at the LHeC

    NASA Astrophysics Data System (ADS)

    Li, Ruibo; Shen, Xiao-Min; Wang, Kai; Xu, Tao; Zhang, Liangliang; Zhu, Guohuai

    2018-04-01

    The precision measurement of the W W γ vertex at the future Large Hadron electron Collider (LHeC) at CERN is discussed in this paper. We propose to measure this vertex in the e-p →e-W±j channel as a complement to the conventional charged current νeγ j channel. In addition to the cross section measurement, χ2 method studies of angular variables provide powerful tools to probe the anomalous structure of triple gauge boson couplings. We study the distribution of the well-known azimuthal angle between the final state forward electron and jet in this vector-boson fusion process. On the other hand, full reconstruction of leptonic W decay opens a new opportunity to measure W polarization that is also sensitive to the anomalous triple gauge boson couplings. Taking into consideration the superior determination of parton distribution functions based on future LHeC data, the constraints of λγ and Δ κγ might reach up to O (10-3) level in the most ideal case with the 2 - 3 ab-1 data set, which shows a potential advantage compared to those from LHC and Large Electron-Positron Collider (LEP) data.

  11. Meteors with anomalous apparent heights from TV observations in Kyiv

    NASA Astrophysics Data System (ADS)

    Kozak, P.

    2017-12-01

    Basing on additional studying and précised processing of video-records of double-station meteor TV observations in Astronomical Observatory of Taras Shevchenko National University of Kyiv the selection of meteors with anomalous photometrical and kinematical characteristics has been carried out. A special attention was paid to the registration of meteors on extreme heights exceeding 130km. In opposite to practically proved at the moment facts about appearance of fast bright bolides created by massive bodies belonging to Leonids, Perseids and Orionids streams on heights over 130-135km, and up to even 160-195km we obtained the confirmation of appearance on the anomalous heights of low-light meteors of masses 10-3g. In 1993 during observations of Perseid meteor shower we registered for the first time the shower meteor with apparent height of 136.84 - 0.12km. In 2001 and 2003 during September observations of sporadic meteors we registered only one meteor from 98 on the height over 135km. During observations of Leonids meteor storm in 2002 we registered five relatively low-light meteors belonging to the shower with apparent heights exceeding 135-140km with masses 10^-3 g.

  12. Fast relaxations in foam

    NASA Astrophysics Data System (ADS)

    Krishan, Kapilanjan; Helal, Ahmed; Höhler, Reinhard; Cohen-Addad, Sylvie

    2010-07-01

    Aqueous foams present an anomalous macroscopic viscoelastic response at high frequency, previously shown to arise from collective relaxations in the disordered bubble packing. We demonstrate experimentally how these mesoscopic dynamics are in turn tuned by physico-chemical processes on the scale of the gas-liquid interfaces. Two specific local dissipation processes are identified, and we show how the rigidity of the interfaces selects the dominant one, depending on the choice of the surfactant.

  13. Fractional Diffusion Processes: Probability Distributions and Continuous Time Random Walk

    NASA Astrophysics Data System (ADS)

    Gorenflo, R.; Mainardi, F.

    A physical-mathematical approach to anomalous diffusion may be based on generalized diffusion equations (containing derivatives of fractional order in space or/and time) and related random walk models. By the space-time fractional diffusion equation we mean an evolution equation obtained from the standard linear diffusion equation by replacing the second-order space derivative with a Riesz-Feller derivative of order alpha in (0,2] and skewness theta (\\verttheta\\vertlemin \\{alpha ,2-alpha \\}), and the first-order time derivative with a Caputo derivative of order beta in (0,1] . The fundamental solution (for the Cauchy problem) of the fractional diffusion equation can be interpreted as a probability density evolving in time of a peculiar self-similar stochastic process. We view it as a generalized diffusion process that we call fractional diffusion process, and present an integral representation of the fundamental solution. A more general approach to anomalous diffusion is however known to be provided by the master equation for a continuous time random walk (CTRW). We show how this equation reduces to our fractional diffusion equation by a properly scaled passage to the limit of compressed waiting times and jump widths. Finally, we describe a method of simulation and display (via graphics) results of a few numerical case studies.

  14. On time-dependent diffusion coefficients arising from stochastic processes with memory

    NASA Astrophysics Data System (ADS)

    Carpio-Bernido, M. Victoria; Barredo, Wilson I.; Bernido, Christopher C.

    2017-08-01

    Time-dependent diffusion coefficients arise from anomalous diffusion encountered in many physical systems such as protein transport in cells. We compare these coefficients with those arising from analysis of stochastic processes with memory that go beyond fractional Brownian motion. Facilitated by the Hida white noise functional integral approach, diffusion propagators or probability density functions (pdf) are obtained and shown to be solutions of modified diffusion equations with time-dependent diffusion coefficients. This should be useful in the study of complex transport processes.

  15. Detection of oxygen isotopic anomaly in terrestrial atmospheric carbonates and its implications to Mars.

    PubMed

    Shaheen, R; Abramian, A; Horn, J; Dominguez, G; Sullivan, R; Thiemens, Mark H

    2010-11-23

    The debate of life on Mars centers around the source of the globular, micrometer-sized mineral carbonates in the ALH84001 meteorite; consequently, the identification of Martian processes that form carbonates is critical. This paper reports a previously undescribed carbonate formation process that occurs on Earth and, likely, on Mars. We identified micrometer-sized carbonates in terrestrial aerosols that possess excess (17)O (0.4-3.9‰). The unique O-isotopic composition mechanistically describes the atmospheric heterogeneous chemical reaction on aerosol surfaces. Concomitant laboratory experiments define the transfer of ozone isotopic anomaly to carbonates via hydrogen peroxide formation when O(3) reacts with surface adsorbed water. This previously unidentified chemical reaction scenario provides an explanation for production of the isotopically anomalous carbonates found in the SNC (shergottites, nakhlaites, chassignites) Martian meteorites and terrestrial atmospheric carbonates. The anomalous hydrogen peroxide formed on the aerosol surfaces may transfer its O-isotopic signature to the water reservoir, thus producing mass independently fractionated secondary mineral evaporites. The formation of peroxide via heterogeneous chemistry on aerosol surfaces also reveals a previously undescribed oxidative process of utility in understanding ozone and oxygen chemistry, both on Mars and Earth.

  16. SPECIAL ISSUE DEVOTED TO THE 80TH ANNIVERSARY OF ACADEMICIAN N G BASOV'S BIRTH: Structural rearrangements in the aqueous phase of cell suspensions and protein solutions induced by a light-oxygen effect

    NASA Astrophysics Data System (ADS)

    Zakharov, S. D.; Ivanov, Andrei V.; Wolf, E. B.; Danilov, V. P.; Murina, T. M.; Nguen, K. T.; Novikov, E. G.; Panasenko, N. A.; Perov, S. N.; Skopinov, S. A.; Timofeev, Yu P.

    2003-02-01

    Temperature-dependent transient processes initiated by a direct photogeneration of singlet oxygen in suspensions of human erythrocytes and solutions of serum albumin are studied. The processes appear as anomalous jumps in the temperature dependences of the deformability coefficient of erythrocytes and the refractive index of the extracellular medium and protein solution. In the temperature regions of anomalous jumps, cells and proteins transfer to a metastable state of a lower activity, but they can be isothermally photoreactivated. Simultaneously, a reversible rearrangement of the aqueous phase occurs near the cell and protein surfaces, accompanied by the formation of an extended corona (hydrogel). The transient processes are interpreted as phase transitions in the membrane of erythrocytes and conformation transitions in proteins. The interaction between erythrocytes and albumin via hydrogel is discovered (hydro-conformational interaction). A qualitative physical model of the early stages of the light-oxygen effect is proposed, in which collective magnetic interactions between the electron spins of oxygen molecules and the nuclear magnetic moments of protons in H2O molecules play a dominant role.

  17. Detection of oxygen isotopic anomaly in terrestrial atmospheric carbonates and its implications to Mars

    PubMed Central

    Shaheen, R.; Abramian, A.; Horn, J.; Dominguez, G.; Sullivan, R.; Thiemens, Mark H.

    2010-01-01

    The debate of life on Mars centers around the source of the globular, micrometer-sized mineral carbonates in the ALH84001 meteorite; consequently, the identification of Martian processes that form carbonates is critical. This paper reports a previously undescribed carbonate formation process that occurs on Earth and, likely, on Mars. We identified micrometer-sized carbonates in terrestrial aerosols that possess excess 17O (0.4–3.9‰). The unique O-isotopic composition mechanistically describes the atmospheric heterogeneous chemical reaction on aerosol surfaces. Concomitant laboratory experiments define the transfer of ozone isotopic anomaly to carbonates via hydrogen peroxide formation when O3 reacts with surface adsorbed water. This previously unidentified chemical reaction scenario provides an explanation for production of the isotopically anomalous carbonates found in the SNC (shergottites, nakhlaites, chassignites) Martian meteorites and terrestrial atmospheric carbonates. The anomalous hydrogen peroxide formed on the aerosol surfaces may transfer its O-isotopic signature to the water reservoir, thus producing mass independently fractionated secondary mineral evaporites. The formation of peroxide via heterogeneous chemistry on aerosol surfaces also reveals a previously undescribed oxidative process of utility in understanding ozone and oxygen chemistry, both on Mars and Earth. PMID:21059939

  18. Anomalous nuclear Overhauser effects in carbon-substituted aziridines: scalar cross-relaxation of the first kind.

    PubMed

    Kuprov, Ilya; Hodgson, David M; Kloesges, Johannes; Pearson, Christopher I; Odell, Barbara; Claridge, Timothy D W

    2015-03-16

    Anomalous NOESY cross-peaks that cannot be explained by dipolar cross-relaxation or chemical exchange are described for carbon-substituted aziridines. The origin of these is identified as scalar cross-relaxation of the first kind, as demonstrated by a complete theoretical description of this relaxation process and by computational simulation of the NOESY spectra. It is shown that this process relies on the stochastic modulation of J-coupling by conformational transitions, which in the case of aziridines arise from inversion at the nitrogen center. The observation of scalar cross-relaxation between protons does not appear to have been previously reported for NOESY spectra. Conventional analysis would have assigned the cross-peaks as being indicative of a chemical exchange process occurring between correlated spins, were it not for the fact that the pairs of nuclei displaying them cannot undergo such exchange. © 2015 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

  19. 3D Numerical Examination of Continental Mantle Lithosphere Response to Lower Crust Eclogitization and Nearby Slab Subduction

    NASA Astrophysics Data System (ADS)

    Janbakhsh, P.; Pysklywec, R.

    2017-12-01

    2D numerical modeling techniques have made great contribution to understanding geodynamic processes involved in crustal and lithospheric scale deformations for the past 20 years. The aim of this presentation is to expand the scope covered by previous researchers to 3 dimensions to address out-of-plane intrusion and extrusion of mantle material in and out of model space, and toroidal mantle wedge flows. In addition, 3D velocity boundary conditions can create more realistic models to replicate real case scenarios. 3D numerical experiments that will be presented are designed to investigate the density and viscosity effects of lower crustal eclogitization on the decoupling process of continental mantle lithosphere from the crust and its delamination. In addition, these models examine near-field effects of a subducting ocean lithosphere and a lithospheric scale fault zone on the evolution of the processes. The model solutions and predictions will also be compared against the Anatolian geology where subduction of Aegean and Arabian slabs, and the northern boundary with the North Anatolian Fault Zone are considered as two main contributing factors to anomalous crustal uplift, missing mantle lithosphere, and anomalous surface heat flux.

  20. A Study of the Magnetic Fingerprint of Tsunami Induced Deposits in the Ixtapa-Zihuatanejo Area (Western Mexico)

    NASA Astrophysics Data System (ADS)

    Goguitchaichrili, A.; Ramirez-Herrera, M.; Calvo-Rathert, M.; Aguilar, B.; Carrancho, Alonso; Morales, J.; Caballero, C. I.; Bautista, F.

    2013-05-01

    The Pacific coast of Mexico has repeatedly been exposed to destructive tsunamis. Recent studies have shown that rock-magnetic methods can be a promising approach for identification of tsunami or storm induced deposits. We present new rock-magnetic and anisotropy of magnetic susceptibility results to try to distinguish tsunami deposits in the Ixtapa-Zihuatanejo area (Western Mexico). The sampled, 80 cm deep sequence is characterised by the presence of two anomalous sand beds within fine-grained coastal deposits. The first lower lying sand bed is probably associated with the 14th March 1979 Petatlán earthquake (MW = 7.6) while the second one was originated by the September 21st 1985 Mexico earthquake (MW = 8.1). Rock magnetic experiments have shown significant variations within the analysed sequence. Thermomagnetic curves reveal two types of behaviour: In the upper part of the sequence, after the occurrence of the first tsunami and in the lower part of the sequence, during that event and below. Analysis of hysteresis parameter ratios in a Day-plot also allows distinguishing two kinds of behaviour. The samples associated to the second tsunami plot in the PSD area, while specimens associated to the first tsunami and the time between both tsunamis display a very different trend which can be ascribed to the production of a considerable amount of superparamagnetic grains which might be due to pedogenic processes after the first tsunami. The studied profile is characterised by a sedimentary fabric with almost vertical minimum principal susceptibilities. The maximum susceptibility axis shows a declination angle D = 27, suggesting a NNE flow direction which is equal for both tsunamis and normal currents. The standard AMS parameters display a significant enhancement within the transitional zone between both tsunamis. The study of rock-magnetic parameters may represent a useful tool for the identification and understanding of tsunami deposits.

  1. Tunable anisotropic anomalous Nernst effect and orbital magnetization in Floquet Weyl semimetals

    NASA Astrophysics Data System (ADS)

    Niu, Zhi Ping; Wu, Xueshi

    2018-03-01

    Weyl semimetals and nodal line semimetals display a host of novel properties. Floquet Weyl semimetals with tunable Weyl points can be obtained from nodal line semimetals under the circularly polarized off-resonant light. Here we theoretically investigate the anomalous Nernst effect and orbital magnetization in Floquet Weyl semimetals. Due to the anisotropy of the band structure in Floquet Weyl semimetals, highly anisotropic Berry phase mediated anomalous Nernst effect and orbital magnetization in the absence of magnetic field are observed, indicating orientation-dependent applications in the design of nanodevices. The amplitude and sign of anomalous Nernst coefficient and orbital magnetization can be tuned by the light direction, amplitude and polarization. The effect of the chemical potential on anomalous Nernst coefficient and orbital magnetization is also discussed. The light-modulated anomalous Nernst effect and orbital magnetization make Floquet Weyl semimetals potential candidates for thermoelectric devices.

  2. Behavioural Change in Type 1 Diabetes Self-Management: Why and How?

    ERIC Educational Resources Information Center

    Wilson, Valerie L.

    2009-01-01

    Objective: To examine whether the communication process between diabetes health professionals and people intensively self-managing their type 1 diabetes influenced behavioural change. Design: Telephone interviews to provide insight into the communication process and its influence on diabetes intensive self-management behaviour. Setting:…

  3. Behaviour Centred Design: towards an applied science of behaviour change.

    PubMed

    Aunger, Robert; Curtis, Valerie

    2016-12-01

    Behaviour change has become a hot topic. We describe a new approach, Behaviour Centred Design (BCD), which encompasses a theory of change, a suite of behavioural determinants and a programme design process. The theory of change is generic, assuming that successful interventions must create a cascade of effects via environments, through brains, to behaviour and hence to the desired impact, such as improved health. Changes in behaviour are viewed as the consequence of a reinforcement learning process involving the targeting of evolved motives and changes to behaviour settings, and are produced by three types of behavioural control mechanism (automatic, motivated and executive). The implications are that interventions must create surprise, revalue behaviour and disrupt performance in target behaviour settings. We then describe a sequence of five steps required to design an intervention to change specific behaviours: Assess, Build, Create, Deliver and Evaluate. The BCD approach has been shown to change hygiene, nutrition and exercise-related behaviours and has the advantages of being applicable to product, service or institutional design, as well as being able to incorporate future developments in behaviour science. We therefore argue that BCD can become the foundation for an applied science of behaviour change.

  4. Behaviour Centred Design: towards an applied science of behaviour change

    PubMed Central

    Aunger, Robert; Curtis, Valerie

    2016-01-01

    ABSTRACT Behaviour change has become a hot topic. We describe a new approach, Behaviour Centred Design (BCD), which encompasses a theory of change, a suite of behavioural determinants and a programme design process. The theory of change is generic, assuming that successful interventions must create a cascade of effects via environments, through brains, to behaviour and hence to the desired impact, such as improved health. Changes in behaviour are viewed as the consequence of a reinforcement learning process involving the targeting of evolved motives and changes to behaviour settings, and are produced by three types of behavioural control mechanism (automatic, motivated and executive). The implications are that interventions must create surprise, revalue behaviour and disrupt performance in target behaviour settings. We then describe a sequence of five steps required to design an intervention to change specific behaviours: Assess, Build, Create, Deliver and Evaluate. The BCD approach has been shown to change hygiene, nutrition and exercise-related behaviours and has the advantages of being applicable to product, service or institutional design, as well as being able to incorporate future developments in behaviour science. We therefore argue that BCD can become the foundation for an applied science of behaviour change. PMID:27535821

  5. The Role of Reversed Equatorial Zonal Transport in Terminating an ENSO Event

    NASA Astrophysics Data System (ADS)

    Chen, H. C.; Hu, Z. Z.; Huang, B.; Sui, C. H.

    2016-02-01

    In this study, we demonstrate that a sudden reversal of anomalous equatorial zonal current at the peaking ENSO phase triggers the rapid termination of an ENSO event. Throughout an ENSO cycle, the anomalous equatorial zonal current is strongly controlled by the concavity of the anomalous thermocline meridional structure near the equator. During the ENSO developing phase, the anomalous zonal current in the central and eastern Pacific generally enhances the ENSO growth through its zonal SST advection. In the mature phase of ENSO, however, the equatorial thermocline depth anomalies are reflected in the eastern Pacific and slowly propagate westward off the equator in both hemispheres. As a result, the concavity of the thermocline anomalies near the equator is reversed, i.e., the off-equatorial thermocline depth anomalies become higher than that on the equator for El Niño events and lower for La Niño events. This meridional change of thermocline structure reverses zonal transport rapidly in the central-to-eastern equatorial Pacific, which weakens the ENSO SST anomalies by reversed advection. More importantly, the reversed zonal mass transport weakens the existing zonal tilting of equatorial thermocline and suppresses the thermocline feedback. Both processes are concentrated in the eastern equatorial Pacific and can be effective on subseasonal time scales. These current reversal effects are built-in to the ENSO peak phase and independent of the zonal wind effect on thermocline slope. It functions as an oceanic control on ENSO evolution during both El Niño and La Niña events.

  6. Enhancement of the spring East China precipitation response to tropical sea surface temperature variability

    NASA Astrophysics Data System (ADS)

    Zhang, Mengqi; Sun, Jianqi

    2017-12-01

    The boreal spring relationship between variabilities of East China precipitation (ECP) and tropical Ocean sea surface temperature (SST) during the period 1951-2014 is investigated in this study. The results show that the leading mode of the ECP variability exhibits an enhanced response to the anomalous El Niño-Southern Oscillation (ENSO)-like SST after the late 1970s, when the SST underwent a decadal change, with two positive centers over the eastern tropical Pacific (ETP) and tropical Indian Ocean (TIO). To further understand the relative roles of the ETP and TIO SST anomalies (SSTAs) in the variability of ECP after the late 1970s, partial regression and correlation methods are used. It is found that, without the contribution of the TIO, ETP SSTA plays a limited role in the variability of ECP after the late 1970s; comparatively, a significant correlation between TIO SST and ECP is identified during the same period, when the ETP signal is linearly removed. Physical analyses show that, after the late 1970s, the TIO SSTA affects East Asian atmospheric circulation in two ways: by exciting a zonal wave-train pattern over the mid-latitude Eurasian Continent and by inducing anomalous convection over the Maritime Continent. Via these two mechanisms, the TIO SST variability results in an anomalous East Asian trough and vertical motion over East China and consequently leads to anomalous precipitation over the region. The physical processes linking the ECP and TIO SST are confirmed by an atmospheric general circulation model experiment forced with idealized TIO warming.

  7. Dehydration of chlorite explains anomalously high electrical conductivity in the mantle wedges.

    PubMed

    Manthilake, Geeth; Bolfan-Casanova, Nathalie; Novella, Davide; Mookherjee, Mainak; Andrault, Denis

    2016-05-01

    Mantle wedge regions in subduction zone settings show anomalously high electrical conductivity (~1 S/m) that has often been attributed to the presence of aqueous fluids released by slab dehydration. Laboratory-based measurements of the electrical conductivity of hydrous phases and aqueous fluids are significantly lower and cannot readily explain the geophysically observed anomalously high electrical conductivity. The released aqueous fluid also rehydrates the mantle wedge and stabilizes a suite of hydrous phases, including serpentine and chlorite. In this present study, we have measured the electrical conductivity of a natural chlorite at pressures and temperatures relevant for the subduction zone setting. In our experiment, we observe two distinct conductivity enhancements when chlorite is heated to temperatures beyond its thermodynamic stability field. The initial increase in electrical conductivity to ~3 × 10(-3) S/m can be attributed to chlorite dehydration and the release of aqueous fluids. This is followed by a unique, subsequent enhancement of electrical conductivity of up to 7 × 10(-1) S/m. This is related to the growth of an interconnected network of a highly conductive and chemically impure magnetite mineral phase. Thus, the dehydration of chlorite and associated processes are likely to be crucial in explaining the anomalously high electrical conductivity observed in mantle wedges. Chlorite dehydration in the mantle wedge provides an additional source of aqueous fluid above the slab and could also be responsible for the fixed depth (120 ± 40 km) of melting at the top of the subducting slab beneath the subduction-related volcanic arc front.

  8. Electrical transport properties in Co nanocluster-assembled granular film

    NASA Astrophysics Data System (ADS)

    Zhang, Qin-Fu; Wang, Lai-Sen; Wang, Xiong-Zhi; Zheng, Hong-Fei; Liu, Xiang; Xie, Jia; Qiu, Yu-Long; Chen, Yuanzhi; Peng, Dong-Liang

    2017-03-01

    A Co nanocluster-assembled granular film with three-dimensional cross-connection paralleled conductive paths was fabricated by using the plasma-gas-condensation method in a vacuum environment. The temperature-dependent longitudinal resistivity and anomalous Hall effect of this new type granular film were systematically studied. The longitudinal resistivity of the Co nanocluster-assembled granular film first decreased and then increased with increasing measuring temperature, revealing a minimum value at certain temperature, T min . In a low temperature region ( T < T min ), the barrier between adjacent nanoclusters governed the electrical transport process, and the temperature coefficient of resistance (TCR) showed an insulator-type behavior. The thermal fluctuation-induced tunneling conduction progressively increased with increasing temperature, which led to a decrease in the longitudinal resistivity. In a high temperature region, the TCR showed a metallic-type behavior, which was primarily attributed to the temperature-dependent scattering. Different from the longitudinal resistivity behavior, the saturated anomalous Hall resistivity increased monotonically with increasing measuring temperature. The value of the anomalous Hall coefficient ( R S ) reached 2.3 × 10-9 (Ω cm)/G at 300 K, which was about three orders of magnitude larger than previously reported in blocky single-crystal Co [E. N. Kondorskii, Sov. Phys. JETP 38, 977 (1974)]. Interestingly, the scaling relation ( ρx y A ∝ ρx x γ ) between saturated anomalous Hall resistivity ( ρx y A ) and longitudinal resistivity ( ρ x x ) was divided into two regions by T min . However, after excluding the contribution of tunneling, the scaling relation followed the same rule. The corresponding physical mechanism was also proposed to explain these phenomena.

  9. Dehydration of chlorite explains anomalously high electrical conductivity in the mantle wedges

    PubMed Central

    Manthilake, Geeth; Bolfan-Casanova, Nathalie; Novella, Davide; Mookherjee, Mainak; Andrault, Denis

    2016-01-01

    Mantle wedge regions in subduction zone settings show anomalously high electrical conductivity (~1 S/m) that has often been attributed to the presence of aqueous fluids released by slab dehydration. Laboratory-based measurements of the electrical conductivity of hydrous phases and aqueous fluids are significantly lower and cannot readily explain the geophysically observed anomalously high electrical conductivity. The released aqueous fluid also rehydrates the mantle wedge and stabilizes a suite of hydrous phases, including serpentine and chlorite. In this present study, we have measured the electrical conductivity of a natural chlorite at pressures and temperatures relevant for the subduction zone setting. In our experiment, we observe two distinct conductivity enhancements when chlorite is heated to temperatures beyond its thermodynamic stability field. The initial increase in electrical conductivity to ~3 × 10−3 S/m can be attributed to chlorite dehydration and the release of aqueous fluids. This is followed by a unique, subsequent enhancement of electrical conductivity of up to 7 × 10−1 S/m. This is related to the growth of an interconnected network of a highly conductive and chemically impure magnetite mineral phase. Thus, the dehydration of chlorite and associated processes are likely to be crucial in explaining the anomalously high electrical conductivity observed in mantle wedges. Chlorite dehydration in the mantle wedge provides an additional source of aqueous fluid above the slab and could also be responsible for the fixed depth (120 ± 40 km) of melting at the top of the subducting slab beneath the subduction-related volcanic arc front. PMID:27386526

  10. Is Onsager symmetry relevant in the transport equations for magnetically confined plasmas

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Balescu, R.

    1991-03-01

    A global, algebraic view of the transport processes in a magnetically confined plasma is developed. Both the neoclassical (banana) and the anomalous transport matrices are represented in a factorized form, thus separating the roles of the dynamics and of the geometric constraints. The self-adjointness of the collision operator (the sole condition for classical Onsager symmetry) is shown to be a necessary, but not sufficient condition for this symmetry in confined plasmas. The latter results for the banana transport matrix from a delicate relationship between dynamic and geometric components. This structure is not present in the anomalous transport matrix, and themore » Onsager symmetry is broken in this case. It is stressed that the symmetry breaking does not violate any general principles.« less

  11. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Schulze, Markus; Soreq, Yotam

    Here, we consider hadronic top quark pair production and pair production in association with a photon or a Z boson to probe electroweak dipole couplings in tb¯W, tt¯γ, and tt¯Z interactions. We demonstrate how measurements of these processes at the 13 TeV LHC can be combined to disentangle and constrain anomalous dipole operators. The construction of cross section ratios allows us to significantly reduce various uncertainties and exploit orthogonal sensitivity between the tt¯γ and tt¯Z couplings. In addition, we show that angular correlations in tt¯ production can be used to constrain the remaining tb¯W dipole operator. Our approach yields excellentmore » sensitivity to the anomalous couplings and can be a further step toward precise and direct measurements of the top quark electroweak interactions.« less

  12. Coherent structures and anomalous transport in reversed field pinch plasmas

    NASA Astrophysics Data System (ADS)

    Antoni, V.; Drake, J. R.; Spada, E.; Spolaore, M.; Vianello, N.; Bergsåker, H.; Cavazzana, R.; Cecconello, M.; Martines, E.; Serianni, G.

    2006-02-01

    The results leading to the identification of coherent structures emerging from the background turbulence in the edge region of the reversed field pinch experiments EXTRAP-T2R and RFX are reviewed. These structures have traits of vortices in velocity field and blobs in density, and the reconstruction of their spatial structure and of their time evolution is discussed focusing on the analysis tools applied. The role of these structures in the particle anomalous transport is addressed, showing that their collisions can contribute up to 50% the total particle losses.This process is shown to be responsible for bursts in particle flux and it is found to set a characteristic collision time, which is in agreement with the statistical properties of laminar times for particle flux bursts.

  13. Fractional Brownian motion with a reflecting wall

    NASA Astrophysics Data System (ADS)

    Wada, Alexander H. O.; Vojta, Thomas

    2018-02-01

    Fractional Brownian motion, a stochastic process with long-time correlations between its increments, is a prototypical model for anomalous diffusion. We analyze fractional Brownian motion in the presence of a reflecting wall by means of Monte Carlo simulations. Whereas the mean-square displacement of the particle shows the expected anomalous diffusion behavior ˜tα , the interplay between the geometric confinement and the long-time memory leads to a highly non-Gaussian probability density function with a power-law singularity at the barrier. In the superdiffusive case α >1 , the particles accumulate at the barrier leading to a divergence of the probability density. For subdiffusion α <1 , in contrast, the probability density is depleted close to the barrier. We discuss implications of these findings, in particular, for applications that are dominated by rare events.

  14. How anomalous is the interstellar extinction in NGC 3372, the Carina Nebula?

    NASA Astrophysics Data System (ADS)

    Tapia, M.; Roth, M.; Marraco, H.; Ruiz, M. T.

    Near-infrared JHKL photometry of more than 200 stars in the open clusters Tr 14, Tr 15, Tr 16, Cr 228, and Cr 232 in the Carina Nebula is presented. By comparing these results with the available visual photometry and spectroscopy, it is found that the intracluster reddening is characterized, except in Tr 15, by a 'normal' extinction law for lambda greater than 0.5 micron, but is highly anomalous and variable in the U and B bands. Provisional two-color visual polarimetry suggests that the wavelength of maximum polarization is similar to that in the general interstellar medium. This behavior may be explained by the presence of intracluster interstellar grains 'processed' by the passage of shock waves, presumably associated with the violent history of Eta Carinae.

  15. An investigation of the effect of athletes' age on the coaching behaviours of professional top-level youth soccer coaches.

    PubMed

    Partington, Mark; Cushion, Christopher; Harvey, Stephen

    2014-01-01

    The aim of the study was to investigate the behaviours, cognitive processes and practice activities of 12 English youth professional soccer coaches across 6 different age groups. Systematic observation data were collected using a modified version of the Coach Analysis and Intervention System which provided a detailed analysis of coaching behaviours performed during practice. Interpretive interviews were then triangulated with the behavioural data to identify the cognitive processes underlying the behaviours performed. The behavioural results showed that the coaches of the younger age groups used more instruction and the coaches of the older age groups used more divergent questioning and significantly more total feedback and punitive behaviours. The coaches of the younger age groups used more training form activities than the coaches of the older age groups who used more playing form activities. However, the interviews revealed that instead of the age of athletes' directly affecting the cognitive process of coaches it was in fact the coaches underlying beliefs about coaching, their previous experiences and perceived pressures from the context that determined the behaviours performed.

  16. Turbulent transport in 2D collisionless guide field reconnection

    NASA Astrophysics Data System (ADS)

    Muñoz, P. A.; Büchner, J.; Kilian, P.

    2017-02-01

    Transport in hot and dilute, i.e., collisionless, astrophysical and space, plasmas is called "anomalous." This transport is due to the interaction between the particles and the self-generated turbulence by their collective interactions. The anomalous transport has very different and not well known properties compared to the transport due to binary collisions, dominant in colder and denser plasmas. Because of its relevance for astrophysical and space plasmas, we explore the excitation of turbulence in current sheets prone to component- or guide-field reconnection, a process not well understood yet. This configuration is typical for stellar coronae, and it is created in the laboratory for which a 2.5D geometry applies. In our analysis, in addition to the immediate vicinity of the X-line, we also include regions outside and near the separatrices. We analyze the anomalous transport properties by using 2.5D Particle-in-Cell code simulations. We split off the mean slow variation (in contrast to the fast turbulent fluctuations) of the macroscopic observables and determine the main transport terms of the generalized Ohm's law. We verify our findings by comparing with the independently determined slowing-down rate of the macroscopic currents (due to a net momentum transfer from particles to waves) and with the transport terms obtained by the first order correlations of the turbulent fluctuations. We find that the turbulence is most intense in the "low density" separatrix region of guide-field reconnection. It is excited by streaming instabilities, is mainly electrostatic and "patchy" in space, and so is the associated anomalous transport. Parts of the energy exchange between turbulence and particles are reversible and quasi-periodic. The remaining irreversible anomalous resistivity can be parametrized by an effective collision rate ranging from the local ion-cyclotron to the lower-hybrid frequency. The contributions to the parallel and the perpendicular (to the magnetic field) components of the slowly varying DC-electric fields, balanced by the turbulence, are similar. This anomalous electric field is, however, smaller than the contributions of the off-diagonal pressure and electron inertia terms of Ohm's law. This result can now be verified by in-situ measurements of the turbulence, in and around the magnetic reconnection regions of the Earth's magnetosphere by the multi-spacecraft mission MMS and in laboratory experiments like MRX and VINETA-II.

  17. The interaction of affective with psychotic processes: A test of the effects of worrying on working memory, jumping to conclusions, and anomalies of experience in patients with persecutory delusions

    PubMed Central

    Freeman, Daniel; Startup, Helen; Dunn, Graham; Černis, Emma; Wingham, Gail; Pugh, Katherine; Cordwell, Jacinta; Kingdon, David

    2013-01-01

    Worry has traditionally been considered in the study of common emotional disorders such as anxiety and depression, but recent studies indicate that worry may be a causal factor in the occurrence and persistence of persecutory delusions. The effect of worry on processes traditionally associated with psychosis has not been tested. The aim of the study was to examine the short-term effects of a bout of worry on three cognitive processes typically considered markers of psychosis: working memory, jumping to conclusions, and anomalous internal experience. Sixty-seven patients with persecutory delusions in the context of a non-affective psychotic disorder were randomised to a worry induction, a worry reduction, or a neutral control condition. They completed tests of the cognitive processes before and after the randomisation condition. The worry induction procedure led to a significant increase in worry. The induction of worry did not affect working memory or jumping to conclusions, but it did increase a range of mild anomalous experiences including feelings of unreality, perceptual alterations, and temporal disintegration. Worry did not affect the occurrence of hallucinations. The study shows that a period of worry causes a range of subtle odd perceptual disturbances that are known to increase the likelihood of delusions. It demonstrates an interaction between affective and psychotic processes in patients with delusions. PMID:23871449

  18. Anomalous magnon Nernst effect of topological magnonic materials

    NASA Astrophysics Data System (ADS)

    Wang, X. S.; Wang, X. R.

    2018-05-01

    The magnon transport driven by a thermal gradient in a perpendicularly magnetized honeycomb lattice is studied. The system with the nearest-neighbor pseudodipolar interaction and the next-nearest-neighbor Dzyaloshinskii–Moriya interaction has various topologically nontrivial phases. When an in-plane thermal gradient is applied, a transverse in-plane magnon current is generated. This phenomenon is termed as the anomalous magnon Nernst effect that closely resembles the anomalous Nernst effect for an electronic system. The anomalous magnon Nernst coefficient and its sign are determined by the magnon Berry curvature distributions in the momentum space and magnon populations in the magnon bands. We predict a temperature-induced sign reversal in anomalous magnon Nernst effect under certain conditions.

  19. Crystallographic Phasing from Weak Anomalous Signals

    PubMed Central

    Liu, Qun; Hendrickson, Wayne A.

    2015-01-01

    The exploitation of anomalous signals for biological structural solution is maturing. Single-wavelength anomalous diffraction (SAD) is dominant in de novo structure analysis. Nevertheless, for challenging structures where the resolution is low (dmin ≥ 3.5 Å) or where only lighter atoms (Z ≤ 20) are present, as for native macromolecules, solved SAD structures are still scarce. With the recent rapid development in crystal handling, beamline instrumentation, optimization of data collection strategies, use of multiple crystals and structure determination technologies, the weak anomalous diffraction signals are now robustly measured and should be used for routine SAD structure determination. The review covers these recent advances on weak anomalous signals measurement, analysis and utilization. PMID:26432413

  20. Crystallographic phasing from weak anomalous signals.

    PubMed

    Liu, Qun; Hendrickson, Wayne A

    2015-10-01

    The exploitation of anomalous signals for biological structural solution is maturing. Single-wavelength anomalous diffraction (SAD) is dominant in de novo structure analysis. Nevertheless, for challenging structures where the resolution is low (dmin≥3.5Å) or where only lighter atoms (Z≤20) are present, as for native macromolecules, solved SAD structures are still scarce. With the recent rapid development in crystal handling, beamline instrumentation, optimization of data collection strategies, use of multiple crystals and structure determination technologies, the weak anomalous diffraction signals are now robustly measured and should be used for routine SAD structure determination. The review covers these recent advances on weak anomalous signals measurement, analysis and utilization. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Structurally Caused Freezing Point Depression of Biological Tissues

    PubMed Central

    Bloch, Rene; Walters, D. H.; Kuhn, Werner

    1963-01-01

    When investigating the freezing behaviour (by thermal analysis) of the glycerol-extracted adductor muscle of Mytilus edulis it was observed that the temperature of ice formation in the muscular tissue was up to 1.5°C lower than the freezing point of the embedding liquid, a 0.25 N KCl solution with pH = 4.9 with which the tissue had been equilibrated prior to the freezing experiment. A smaller freezing point depression was observed if the pH values of the embedding 0.25 N KCl solution were above or below pH = 4.9. Reasoning from results obtained previously in analogous experiments with artificial gels, the anomalous freezing depression is explained by the impossibility of growing at the normal freezing temperature regular macroscopic crystals inside the gel, due to the presence of the gel network. The freezing temperature is here determined by the size of the microprisms penetrating the meshes of the network at the lowered freezing temperature. This process leads finally to an ice block of more or less regular structure in which the filaments are embedded. Prerequisite for this hindrance of ideal ice growth is a sufficient tensile strength of the filamental network. The existence of structurally caused freezing point depression in biological tissue is likely to invalidate many conclusions reported in the literature, in which hypertonicity was deduced from cryoscopic data. PMID:13971682

  2. Serotoninergic regulation of emotional and behavioural control processes.

    PubMed

    Cools, Roshan; Roberts, Angela C; Robbins, Trevor W

    2008-01-01

    5-Hydroxytryptamine (5-HT, serotonin) has long been implicated in a wide variety of emotional, cognitive and behavioural control processes. However, its precise contribution is still not well understood. Depletion of 5-HT enhances behavioural and brain responsiveness to punishment or other aversive signals, while disinhibiting previously rewarded but now punished behaviours. Findings suggest that 5-HT modulates the impact of punishment-related signals on learning and emotion (aversion), but also promotes response inhibition. Exaggerated aversive processing and deficient response inhibition could underlie distinct symptoms of a range of affective disorders, namely stress- or threat-vulnerability and compulsive behaviour, respectively. We review evidence from studies with human volunteers and experimental animals that begins to elucidate the neurobiological systems underlying these different effects.

  3. Percutaneous intervention of chronic total occlusion of anomalous right coronary artery originating from left sinus – Use of mother and child technique using guideliner

    PubMed Central

    Senguttuvan, Nagendra Boopathy; Sharma, Samin K.; Kini, Annapoorna

    2015-01-01

    Anomalous origin of right coronary artery (RCA) from left sinus is a rare clinical entity. Percutaneous coronary intervention of such an anomalous RCA, which is chronically occluded, is difficult and is rarely described. We describe such an intervention in a patient, who had a chronic total occlusion of anomalous RCA and discuss the technical issues associated with such interventions. PMID:26995429

  4. Thin film growth by 3D multi-particle diffusion limited aggregation model: Anomalous roughening and fractal analysis

    NASA Astrophysics Data System (ADS)

    Nasehnejad, Maryam; Nabiyouni, G.; Gholipour Shahraki, Mehran

    2018-03-01

    In this study a 3D multi-particle diffusion limited aggregation method is employed to simulate growth of rough surfaces with fractal behavior in electrodeposition process. A deposition model is used in which the radial motion of the particles with probability P, competes with random motions with probability 1 - P. Thin films growth is simulated for different values of probability P (related to the electric field) and thickness of the layer(related to the number of deposited particles). The influence of these parameters on morphology, kinetic of roughening and the fractal dimension of the simulated surfaces has been investigated. The results show that the surface roughness increases with increasing the deposition time and scaling exponents exhibit a complex behavior which is called as anomalous scaling. It seems that in electrodeposition process, radial motion of the particles toward the growing seeds may be an important mechanism leading to anomalous scaling. The results also indicate that the larger values of probability P, results in smoother topography with more densely packed structure. We have suggested a dynamic scaling ansatz for interface width has a function of deposition time, scan length and probability. Two different methods are employed to evaluate the fractal dimension of the simulated surfaces which are "cube counting" and "roughness" methods. The results of both methods show that by increasing the probability P or decreasing the deposition time, the fractal dimension of the simulated surfaces is increased. All gained values for fractal dimensions are close to 2.5 in the diffusion limited aggregation model.

  5. Possible Charge-Exchange X-Ray Emission in the Cygnus Loop Detected with Suzaku

    NASA Technical Reports Server (NTRS)

    Katsuda, Satoru; Tsunemi, Hiroshi; Mori, Koji; Uchida, Hiroyuki; Kosugi, Hiroko; Kimura, Masashi; Nakajima, Hiroshi; Takakura, Satoru; Petre, Robert; Hewitt. John W.; hide

    2011-01-01

    X-ray spectroscopic measurements of the Cygnus Loop supernova remnant indicate that metal abundances throughout most of the remnant s rim are depleted to approx.0.2 times the solar value. However, recent X-ray studies have revealed in some narrow regions along the outermost rim anomalously "enhanced" abundances (up to approx. 1 solar). The reason for these anomalous abundances is not understood. Here, we examine X-ray spectra in annular sectors covering nearly the entire rim of the Cygnus Loop using Suzaku (21 pointings) and XMM-Newton (1 pointing). We find that spectra in the "enhanced" abundance regions commonly show a strong emission feature at approx.0.7 keV. This feature is likely a complex of He-like O K(gamma + delta + epsilon), although other possibilities cannot be fully excluded. The intensity of this emission relative to He-like O K(alpha) appears to be too high to be explained as thermal emission. This fact, as well as the spatial concentration of the anomalous abundances in the outermost rim, leads us to propose an origin from charge-exchange processes between neutrals and H-like O. We show that the presence of charge-exchange emission could lead to the inference of apparently "enhanced" metal abundances using pure thermal emission models. Accounting for charge-exchange emission, the actual abundances could be uniformly low throughout the rim. The overall abundance depletion remains an open question. Subject headings: ISM: abundances ISM: individual objects (Cygnus Loop) ISM: supernova remnants X-rays: ISM atomic processes

  6. Creatures of habit: accounting for the role of habit in implementation research on clinical behaviour change

    PubMed Central

    2012-01-01

    Background Social cognitive theories on behaviour change are increasingly being used to understand and predict healthcare professionals’ intentions and clinical behaviours. Although these theories offer important insights into how new behaviours are initiated, they provide an incomplete account of how changes in clinical practice occur by failing to consider the role of cue-contingent habits. This article contributes to better understanding of the role of habits in clinical practice and how improved effectiveness of behavioural strategies in implementation research might be achieved. Discussion Habit is behaviour that has been repeated until it has become more or less automatic, enacted without purposeful thinking, largely without any sense of awareness. The process of forming habits occurs through a gradual shift in cognitive control from intentional to automatic processes. As behaviour is repeated in the same context, the control of behaviour gradually shifts from being internally guided (e.g., beliefs, attitudes, and intention) to being triggered by situational or contextual cues. Much clinical practice occurs in stable healthcare contexts and can be assumed to be habitual. Empirical findings in various fields suggest that behaviours that are repeated in constant contexts are difficult to change. Hence, interventions that focus on changing the context that maintains those habits have a greater probability of success. Some sort of contextual disturbance provides a window of opportunity in which a behaviour is more likely to be deliberately considered. Forming desired habits requires behaviour to be carried out repeatedly in the presence of the same contextual cues. Summary Social cognitive theories provide insight into how humans analytically process information and carefully plan actions, but their utility is more limited when it comes to explaining repeated behaviours that do not require such an ongoing contemplative decisional process. However, despite a growing interest in applying behavioural theory in interventions to change clinical practice, the potential importance of habit has not been explored in implementation research. PMID:22682656

  7. Behaviour of mobile macrofauna is a key factor in beach ecology as response to rapid environmental changes

    NASA Astrophysics Data System (ADS)

    Scapini, Felicita

    2014-10-01

    Sandy beach animals show behavioural adaptations that are expressed as contingencies during the life history of individuals to face periodic and episodic environmental changes. Such adaptations include activity rhythms, orientation, zonation, burrowing, escape responses and feeding strategies, the first two being common adaptations to all mobile animals. The complex conditions of a particular beach environment may be integrated in a learning process enhancing the adaptation and survival of individuals and eventually of populations. Evidence exists of genetic determination of some behavioural features that are adaptive in the long term (throughout generations) by increasing individual survival and reproductive potential. The environmental features integrated with the life history of beach animals shape the individual behaviour through ontogenetic processes, as well as population behaviour through evolutionary processes. Thus, behavioural differences among individuals may reflect environmental variation at the local and small/medium temporal scales of beach processes, whereas within-population behavioural coherence and differences among populations may reflect variation at the geographic scale. The different foci stressed by different authors and the variety of evidence dependent upon local geographical and ecological conditions have often resulted in compartmentalised explanations, making generalizations and the repeatability of behavioural studies of beach ecology challenging. There was a need to developing a more synthetic paradigm for beach animal behaviour. This paper gives a brief overview of the theoretical background and keystone studies, which have contributed to our understanding of animal behaviour in sandy beach ecology, and proposes testable hypotheses to be integrated in the beach ecology paradigm.

  8. Large anomalous Hall effect driven by a nonvanishing Berry curvature in the noncolinear antiferromagnet Mn3Ge.

    PubMed

    Nayak, Ajaya K; Fischer, Julia Erika; Sun, Yan; Yan, Binghai; Karel, Julie; Komarek, Alexander C; Shekhar, Chandra; Kumar, Nitesh; Schnelle, Walter; Kübler, Jürgen; Felser, Claudia; Parkin, Stuart S P

    2016-04-01

    It is well established that the anomalous Hall effect displayed by a ferromagnet scales with its magnetization. Therefore, an antiferromagnet that has no net magnetization should exhibit no anomalous Hall effect. We show that the noncolinear triangular antiferromagnet Mn3Ge exhibits a large anomalous Hall effect comparable to that of ferromagnetic metals; the magnitude of the anomalous conductivity is ~500 (ohm·cm)(-1) at 2 K and ~50 (ohm·cm)(-1) at room temperature. The angular dependence of the anomalous Hall effect measurements confirms that the small residual in-plane magnetic moment has no role in the observed effect except to control the chirality of the spin triangular structure. Our theoretical calculations demonstrate that the large anomalous Hall effect in Mn3Ge originates from a nonvanishing Berry curvature that arises from the chiral spin structure, and that also results in a large spin Hall effect of 1100 (ħ/e) (ohm·cm)(-1), comparable to that of platinum. The present results pave the way toward the realization of room temperature antiferromagnetic spintronics and spin Hall effect-based data storage devices.

  9. Computational Study of Anomalous Transport in High Beta DIII-D Discharges with ITBs

    NASA Astrophysics Data System (ADS)

    Pankin, Alexei; Garofalo, Andrea; Grierson, Brian; Kritz, Arnold; Rafiq, Tariq

    2015-11-01

    The advanced tokamak scenarios require a large bootstrap current fraction and high β. These large values are often outside the range that occurs in ``conventional'' tokamak discharges. The GLF23, TGLF, and MMM transport models have been previously validated for discharges with parameters associated with ``conventional'' tokamak discharges. It has been demonstrated that the TGLF model under-predicts anomalous transport in high β DIII-D discharges [A.M. Garofalo et al. 2015 TTF Workshop]. In this research, the validity of MMM7.1 model [T. Rafiq et al. Phys. Plasmas 20 032506 (2013)] is tested for high β DIII-D discharges with low and high torque. In addition, the sensitivity of the anomalous transport to β is examined. It is shown that the MMM7.1 model over-predicts the anomalous transport in the DIII-D discharge 154406. In particular, a significant level of anomalous transport is found just outside the internal transport barrier. Differences in the anomalous transport predicted using TGLF and MMM7.1 are reviewed. Mechanisms for quenching of anomalous transport in the ITB regions of high-beta discharges are investigated. This research is supported by US Department of Energy.

  10. Relationships between atypical sensory processing patterns, maladaptive behaviour and maternal stress in Spanish children with autism spectrum disorder.

    PubMed

    Nieto, C; López, B; Gandía, H

    2017-12-01

    This study investigated sensory processing in a sample of Spanish children with autism spectrum disorder (ASD). Specifically, the study aimed to explore (1) the prevalence and distribution of atypical sensory processing patterns, (2) the relationship between adaptive and maladaptive behaviour with atypical sensory processing and (3) the possible relationship between sensory subtype and maternal stress. The short sensory profile 2 (Dunn 2014) and the vineland adaptive behavior scale (Sparrow et al. 1984) were administered to examine the sensory processing difficulties and maladaptive behaviours of 45 children with ASD aged 3 to 14; their mothers also completed the parenting stress index-short form (Abidin 1995). Atypical sensory features were found in 86.7% of the children; avoider and sensor being the two most common patterns. No significant relationship was found between atypical sensory processing and adaptive behaviour. However, the analysis showed a strong relationship between sensory processing and maladaptive behaviour. Both maladaptive behaviour and sensory processing difficulties correlated significantly with maternal stress although maternal stress was predicted only by the sensory variable, and in particular by the avoider pattern. The findings suggest that sensory features in ASD may be driving the high prevalence of parental stress in carers. They also suggest that the effect on parental stress that has been attributed traditionally to maladaptive behaviours may be driven by sensory difficulties. The implications of these findings are discussed in relation to the development of interventions and the need to explore contextual and cultural variables as possible sources of variability. © 2017 MENCAP and International Association of the Scientific Study of Intellectual and Developmental Disabilities and John Wiley & Sons Ltd.

  11. Physical and Mathematical Questions on Signal Processing in Multibase Phase Direction Finders

    NASA Astrophysics Data System (ADS)

    Denisov, V. P.; Dubinin, D. V.; Meshcheryakov, A. A.

    2018-02-01

    Questions on improving the accuracy of multiple-base phase direction finders by rejecting anomalously large errors in the process of resolving the measurement ambiguities are considered. A physical basis is derived and calculated relationships characterizing the efficiency of the proposed solutions are obtained. Results of a computer simulation of a three-base direction finder are analyzed, along with field measurements of a three-base direction finder along near-ground paths.

  12. Can self-reported disability assessment behaviour of insurance physicians be explained? Applying the ASE model

    PubMed Central

    2011-01-01

    Background Very little is known about the attitudes and views that might underlie and explain the variation in occupational disability assessment behaviour between insurance physicians. In an earlier study we presented an adjusted ASE model (Attitude, Social norm, Self-efficacy) to identify the determinants of the disability assessment behaviour among insurance physicians. The research question of this study is how Attitude, Social norm, Self-efficacy and Intention shape the behaviour that insurance physicians themselves report with regard to the process (Behaviour: process) and content of the assessment (Behaviour: assessment) while taking account of Knowledge and Barriers. Methods This study was based on 231 questionnaires filled in by insurance physicians, resulting into 48 scales and dimension scores. The number of variables was reduced by a separate estimation of each of the theoretical ASE constructs as a latent variable in a measurement model. The saved factor scores of these latent variables were treated as observed variables when we estimated a path model with Lisrel to confirm the ASE model. We estimated latent ASE constructs for most of the assigned scales and dimensions. All could be described and interpreted. We used these constructs to build a path model that showed a good fit. Results Contrary to our initial expectations, we did not find direct effects for Attitude on Intention and for Intention on self reported assessment behaviour in the model. This may well have been due to the operationalization of the concept of 'Intention'. We did, however, find that Attitude had a positive direct effect on Behaviour: process and Behaviour: Assessment and that Intention had a negative direct effect on Behaviour: process. Conclusion A path model pointed to the existence of relationships between Attitude on the one hand and self-reported behaviour by insurance physicians with regard to process and content of occupational disability assessments on the other hand. In addition, Intention was only related to the self reported behaviour with regard to the process of occupational disability assessments. These findings provide some evidence of the relevance of the ASE model in this setting. Further research is needed to determine whether the ASE variables measured for insurance physicians are related to the real practice outcomes of occupational disability assessments. PMID:21771326

  13. South Asian summer monsoon breaks: Process-based diagnostics in HIRHAM5

    NASA Astrophysics Data System (ADS)

    Hanf, Franziska S.; Annamalai, H.; Rinke, Annette; Dethloff, Klaus

    2017-05-01

    This study assesses the ability of a high-resolution downscaling simulation with the regional climate model (RCM) HIRHAM5 in capturing the monsoon basic state and boreal summer intraseasonal variability (BSISV) over South Asia with focus on moist and radiative processes during 1979-2012. A process-based vertically integrated moist static energy (MSE) budget is performed to understand the model's fidelity in representing leading processes that govern the monsoon breaks over continental India. In the climatology (June-September) HIRHAM5 simulates a dry bias over central India in association with descent throughout the free troposphere. Sources of dry bias are interpreted as (i) near-equatorial Rossby wave response forced by excess rainfall over the southern Bay of Bengal promotes anomalous descent to its northwest and (ii) excessive rainfall over near-equatorial Arabian Sea and Bay of Bengal anchor a "local Hadley-type" circulation with descent anomalies over continental India. Compared with observations HIRHAM5 captures the leading processes that account for breaks, although with generally reduced amplitudes over central India. In the model too, anomalous dry advection and net radiative cooling are responsible for the initiation and maintenance of breaks, respectively. However, weaker contributions of all adiabatic MSE budget terms, and an inconsistent relationship between negative rainfall anomalies and radiative cooling reveals shortcomings in HIRHAM5's moisture-radiation interaction. Our study directly implies that process-based budget diagnostics are necessary, apart from just checking the northward propagation feature to examine RCM's fidelity to simulate BSISV.

  14. Possible combined influences of absorbing aerosols and anomalous atmospheric circulation on summertime diurnal temperature range variation over the middle and lower reaches of the Yangtze River

    NASA Astrophysics Data System (ADS)

    Cai, Jiaxi; Guan, Zhaoyong; Ma, Fenhua

    2016-12-01

    Based on the temperature data from the China Meteorological Administration, NCEP-NCAR reanalysis data, and the TOMS Aerosol Index (AI), we analyze the variations in the summertime diurnal temperature range (DTR) and temperature maxima in the middle and lower reaches of the Yangtze River (MLRYR) in China. The possible relationships between the direct warming effect of the absorbing aerosol and temperature variations are further investigated, although with some uncertainties. It is found that the summertime DTR exhibits a decreasing trend over the most recent 50 years, along with a slight increasing tendency since the 1980s. The trend of the maximum temperature is in agreement with those of the DTR and the absorbing aerosols. To investigate the causes of the large anomalies in the temperature maxima, composite analyses of the circulation anomalies are performed. When anomalous AI and anomalous maximum temperature over the MLRYR have the same sign, an anomalous circulation with a quasi-barotropic structure occurs there. This anomalous circulation is modulated by the Rossby wave energy propagations from the regions northwest of the MLRYR and influences the northwestern Pacific subtropical high over the MLRYR. In combination with aerosols, the anomalous circulation may increase the maximum temperature in this region. Conversely, when the anomalous AI and anomalous maximum temperature in the MLRYR have opposite signs, the anomalous circulation is not equivalently barotropic, which possibly offsets the warming effect of aerosols on the maximum temperature changes in this region. These results are helpful for a better understanding of the DTR changes and the occurrences of temperature extremes in the MLRYR region during boreal summer.

  15. Social Information Processing in Boys with Autistic Spectrum Disorder and Mild to Borderline Intellectual Disabilities

    ERIC Educational Resources Information Center

    Embregts, P.; van Nieuwenhuijzen, M.

    2009-01-01

    Background: Children with autistic spectrum disorders (ASD) and mild to borderline intellectual disability (ID) have less adaptive behaviour and more behaviour problems than children with mild to borderline ID. Social information processing appears to be an important mechanism in the explanation of the socially inadequate behaviour of children…

  16. A Review of Behavioural and Electrophysiological Studies on Auditory Processing and Speech Perception in Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Haesen, Birgitt; Boets, Bart; Wagemans, Johan

    2011-01-01

    This literature review aims to interpret behavioural and electrophysiological studies addressing auditory processing in children and adults with autism spectrum disorder (ASD). Data have been organised according to the applied methodology (behavioural versus electrophysiological studies) and according to stimulus complexity (pure versus complex…

  17. Evolutionary learning processes as the foundation for behaviour change.

    PubMed

    Crutzen, Rik; Peters, Gjalt-Jorn Ygram

    2018-03-01

    We argue that the active ingredients of behaviour change interventions, often called behaviour change methods (BCMs) or techniques (BCTs), can usefully be placed on a dimension of psychological aggregation. We introduce evolutionary learning processes (ELPs) as fundamental building blocks that are on a lower level of psychological aggregation than BCMs/BCTs. A better understanding of ELPs is useful to select the appropriate BCMs/BCTs to target determinants of behaviour, or vice versa, to identify potential determinants targeted by a given BCM/BCT, and to optimally translate them into practical applications. Using these insights during intervention development may increase the likelihood of developing effective interventions - both in terms of behaviour change as well as maintenance of behaviour change.

  18. A longitudinal investigation of older adults' physical activity: Testing an integrated dual-process model.

    PubMed

    Arnautovska, Urska; Fleig, Lena; O'Callaghan, Frances; Hamilton, Kyra

    2017-02-01

    To assess the effects of conscious and non-conscious processes for prediction of older adults' physical activity (PA), we tested a dual-process model that integrated motivational (behavioural intention) and volitional (action planning and coping planning) processes with non-conscious, automatic processes (habit). Participants (N = 215) comprised community-dwelling older adults (M = 73.8 years). A longitudinal design was adopted to investigate direct and indirect effects of intentions, habit strength (Time 1), and action planning and coping planning (Time 2) on PA behaviour (Time 3). Structural equation modelling was used to evaluate the model. The model provided a good fit to the data, accounting for 44% of the variance in PA behaviour at Time 3. PA was predicted by intentions, action planning, and habit strength, with action planning mediating the intention-behaviour relationship. An effect of sex was also found where males used fewer planning strategies and engaged in more PA than females. By investigating an integration of conscious and non-conscious processes, this study provides a novel understanding of older adults' PA. Interventions aiming to promote PA behaviour of older adults should target the combination of psychological processes.

  19. Anomalous Diffraction in Crystallographic Phase Evaluation

    PubMed Central

    Hendrickson, Wayne A.

    2014-01-01

    X-ray diffraction patterns from crystals of biological macromolecules contain sufficient information to define atomic structures, but atomic positions are inextricable without having electron-density images. Diffraction measurements provide amplitudes, but the computation of electron density also requires phases for the diffracted waves. The resonance phenomenon known as anomalous scattering offers a powerful solution to this phase problem. Exploiting scattering resonances from diverse elements, the methods of multiwavelength anomalous diffraction (MAD) and single-wavelength anomalous diffraction (SAD) now predominate for de novo determinations of atomic-level biological structures. This review describes the physical underpinnings of anomalous diffraction methods, the evolution of these methods to their current maturity, the elements, procedures and instrumentation used for effective implementation, and the realm of applications. PMID:24726017

  20. Anomalous pulmonary venous connection: An underestimated entity.

    PubMed

    Magalhães, Sara P; Moreno, Nuno; Loureiro, Marília; França, Manuela; Reis, Fernanda; Alvares, Sílvia; Ribeiro, Manuel

    2016-12-01

    Anomalous pulmonary venous connection is an uncommon congenital anomaly in which all (total form) or some (partial form) pulmonary veins drain into a systemic vein or into the right atrium rather than into the left atrium. The authors present one case of total anomalous pulmonary venous connection and two cases of partial anomalous pulmonary venous connection, one of supracardiac drainage into the brachiocephalic vein, and the other of infracardiac anomalous venous drainage (scimitar syndrome). Through the presentation of these cases, this article aims to review the main pulmonary venous developmental defects, highlighting the role of imaging techniques in the assessment of these anomalies. Copyright © 2016 Sociedade Portuguesa de Cardiologia. Publicado por Elsevier España, S.L.U. All rights reserved.

  1. Anomalous incident-angle and elliptical-polarization rotation of an elastically refracted P-wave

    NASA Astrophysics Data System (ADS)

    Fa, Lin; Fa, Yuxiao; Zhang, Yandong; Ding, Pengfei; Gong, Jiamin; Li, Guohui; Li, Lijun; Tang, Shaojie; Zhao, Meishan

    2015-08-01

    We report a newly discovered anomalous incident-angle of an elastically refracted P-wave, arising from a P-wave impinging on an interface between two VTI media with strong anisotropy. This anomalous incident-angle is found to be located in the post-critical incident-angle region corresponding to a refracted P-wave. Invoking Snell’s law for a refracted P-wave provides two distinctive solutions before and after the anomalous incident-angle. For an inhomogeneously refracted and elliptically polarized P-wave at the anomalous incident-angle, its rotational direction experiences an acute variation, from left-hand elliptical to right-hand elliptical polarization. The new findings provide us an enhanced understanding of acoustical-wave scattering and lead potentially to widespread and novel applications.

  2. Meaningful interpretation of subdiffusive measurements in living cells (crowded environment) by fluorescence fluctuation microscopy.

    PubMed

    Baumann, Gerd; Place, Robert F; Földes-Papp, Zeno

    2010-08-01

    In living cell or its nucleus, the motions of molecules are complicated due to the large crowding and expected heterogeneity of the intracellular environment. Randomness in cellular systems can be either spatial (anomalous) or temporal (heterogeneous). In order to separate both processes, we introduce anomalous random walks on fractals that represented crowded environments. We report the use of numerical simulation and experimental data of single-molecule detection by fluorescence fluctuation microscopy for detecting resolution limits of different mobile fractions in crowded environment of living cells. We simulate the time scale behavior of diffusion times tau(D)(tau) for one component, e.g. the fast mobile fraction, and a second component, e.g. the slow mobile fraction. The less the anomalous exponent alpha the higher the geometric crowding of the underlying structure of motion that is quantified by the ratio of the Hausdorff dimension and the walk exponent d(f)/d(w) and specific for the type of crowding generator used. The simulated diffusion time decreases for smaller values of alpha # 1 but increases for a larger time scale tau at a given value of alpha # 1. The effect of translational anomalous motion is substantially greater if alpha differs much from 1. An alpha value close to 1 contributes little to the time dependence of subdiffusive motions. Thus, quantitative determination of molecular weights from measured diffusion times and apparent diffusion coefficients, respectively, in temporal auto- and crosscorrelation analyses and from time-dependent fluorescence imaging data are difficult to interpret and biased in crowded environments of living cells and their cellular compartments; anomalous dynamics on different time scales tau must be coupled with the quantitative analysis of how experimental parameters change with predictions from simulated subdiffusive dynamics of molecular motions and mechanistic models. We first demonstrate that the crowding exponent alpha also determines the resolution of differences in diffusion times between two components in addition to photophysical parameters well-known for normal motion in dilute solution. The resolution limit between two different kinds of single molecule species is also analyzed under translational anomalous motion with broken ergodicity. We apply our theoretical predictions of diffusion times and lower limits for the time resolution of two components to fluorescence images in human prostate cancer cells transfected with GFP-Ago2 and GFP-Ago1. In order to mimic heterogeneous behavior in crowded environments of living cells, we need to introduce so-called continuous time random walks (CTRW). CTRWs were originally performed on regular lattice. This purely stochastic molecule behavior leads to subdiffusive motion with broken ergodicity in our simulations. For the first time, we are able to quantitatively differentiate between anomalous motion without broken ergodicity and anomalous motion with broken ergodicity in time-dependent fluorescence microscopy data sets of living cells. Since the experimental conditions to measure a selfsame molecule over an extended period of time, at which biology is taken place, in living cells or even in dilute solution are very restrictive, we need to perform the time average over a subpopulation of different single molecules of the same kind. For time averages over subpopulations of single molecules, the temporal auto- and crosscorrelation functions are first found. Knowing the crowding parameter alpha for the cell type and cellular compartment type, respectively, the heterogeneous parameter gamma can be obtained from the measurements in the presence of the interacting reaction partner, e.g. ligand, with the same alpha value. The product alpha x gamma = gamma is not a simple fitting parameter in the temporal auto- and two-color crosscorrelation functions because it is related to the proper physical models of anomalous (spatial) and heterogeneous (temporal) randomness in cellular systems.We have already derived an analytical solution gamma for in the special case of gamma = 3/2. In the case of two-color crosscorrelation or/and two-color fluorescence imaging (co-localization experiments), the second component is also a two-color species gr, for example a different molecular complex with an additional ligand. Here, we first show that plausible biological mechanisms from FCS/ FCCS and fluorescence imaging in living cells are highly questionable without proper quantitative physical models of subdiffusive motion and temporal randomness. At best, such quantitative FCS/ FCCS and fluorescence imaging data are difficult to interpret under crowding and heterogeneous conditions. It is challenging to translate proper physical models of anomalous (spatial) and heterogeneous (temporal) randomness in living cells and their cellular compartments like the nucleus into biological models of the cell biological process under study testable by single-molecule approaches. Otherwise, quantitative FCS/FCCS and fluorescence imaging measurements in living cells are not well described and cannot be interpreted in a meaningful way.

  3. Anomalous Evidence, Confidence Change, and Theory Change.

    PubMed

    Hemmerich, Joshua A; Van Voorhis, Kellie; Wiley, Jennifer

    2016-08-01

    A novel experimental paradigm that measured theory change and confidence in participants' theories was used in three experiments to test the effects of anomalous evidence. Experiment 1 varied the amount of anomalous evidence to see if "dose size" made incremental changes in confidence toward theory change. Experiment 2 varied whether anomalous evidence was convergent (of multiple types) or replicating (similar finding repeated). Experiment 3 varied whether participants were provided with an alternative theory that explained the anomalous evidence. All experiments showed that participants' confidence changes were commensurate with the amount of anomalous evidence presented, and that larger decreases in confidence predicted theory changes. Convergent evidence and the presentation of an alternative theory led to larger confidence change. Convergent evidence also caused more theory changes. Even when people do not change theories, factors pertinent to the evidence and alternative theories decrease their confidence in their current theory and move them incrementally closer to theory change. Copyright © 2015 Cognitive Science Society, Inc.

  4. Approaching quantum anomalous Hall effect in proximity-coupled YIG/graphene/h-BN sandwich structure

    NASA Astrophysics Data System (ADS)

    Tang, Chi; Cheng, Bin; Aldosary, Mohammed; Wang, Zhiyong; Jiang, Zilong; Watanabe, K.; Taniguchi, T.; Bockrath, Marc; Shi, Jing

    2018-02-01

    Quantum anomalous Hall state is expected to emerge in Dirac electron systems such as graphene under both sufficiently strong exchange and spin-orbit interactions. In pristine graphene, neither interaction exists; however, both interactions can be acquired by coupling graphene to a magnetic insulator as revealed by the anomalous Hall effect. Here, we show enhanced magnetic proximity coupling by sandwiching graphene between a ferrimagnetic insulator yttrium iron garnet (YIG) and hexagonal-boron nitride (h-BN) which also serves as a top gate dielectric. By sweeping the top-gate voltage, we observe Fermi level-dependent anomalous Hall conductance. As the Dirac point is approached from both electron and hole sides, the anomalous Hall conductance reaches ¼ of the quantum anomalous Hall conductance 2e2/h. The exchange coupling strength is determined to be as high as 27 meV from the transition temperature of the induced magnetic phase. YIG/graphene/h-BN is an excellent heterostructure for demonstrating proximity-induced interactions in two-dimensional electron systems.

  5. Systematic Serendipity: A Method to Discover the Anomalous

    NASA Astrophysics Data System (ADS)

    Giles, Daniel; Walkowicz, Lucianne

    2018-01-01

    One of the challenges in the era of big data astronomical surveys is identifying anomalous data, data that exhibits as-of-yet unobserved behavior. These data may result from systematic errors, extreme (or rare) forms of known phenomena, or, most interestingly, truly novel phenomena that has historically required a trained eye and often fortuitous circumstance to identify. We describe a method that uses machine clustering techniques to discover anomalous data in Kepler lightcurves, as a step towards systematizing the detection of novel phenomena in the era of LSST. As a proof of concept, we apply our anomaly detection method to Kepler data including Boyajian's Star (KIC 8462852). We examine quarters 4, 8, 11, and 16 of the Kepler data which contain Boyajian’s Star acting normally (quarters 4 and 11) and anomalously (quarters 8 and 16). We demonstrate that our method is capable of identifying Boyajian’s Star’s anomalous behavior in quarters of interest, and we further identify other anomalous light curves that exhibit a range of interesting variability.

  6. Predicting sugar-sweetened behaviours with theory of planned behaviour constructs: Outcome and process results from the SIPsmartER behavioural intervention.

    PubMed

    Zoellner, Jamie M; Porter, Kathleen J; Chen, Yvonnes; Hedrick, Valisa E; You, Wen; Hickman, Maja; Estabrooks, Paul A

    2017-05-01

    Guided by the theory of planned behaviour (TPB) and health literacy concepts, SIPsmartER is a six-month multicomponent intervention effective at improving SSB behaviours. Using SIPsmartER data, this study explores prediction of SSB behavioural intention (BI) and behaviour from TPB constructs using: (1) cross-sectional and prospective models and (2) 11 single-item assessments from interactive voice response (IVR) technology. Quasi-experimental design, including pre- and post-outcome data and repeated-measures process data of 155 intervention participants. Validated multi-item TPB measures, single-item TPB measures, and self-reported SSB behaviours. Hypothesised relationships were investigated using correlation and multiple regression models. TPB constructs explained 32% of the variance cross sectionally and 20% prospectively in BI; and explained 13-20% of variance cross sectionally and 6% prospectively. Single-item scale models were significant, yet explained less variance. All IVR models predicting BI (average 21%, range 6-38%) and behaviour (average 30%, range 6-55%) were significant. Findings are interpreted in the context of other cross-sectional, prospective and experimental TPB health and dietary studies. Findings advance experimental application of the TPB, including understanding constructs at outcome and process time points and applying theory in all intervention development, implementation and evaluation phases.

  7. Working memory load affects repetitive behaviour but not cognitive flexibility in adolescent autism spectrum disorder.

    PubMed

    Wolff, Nicole; Chmielewski, Witold X; Beste, Christian; Roessner, Veit

    2017-03-16

    Autism spectrum disorder (ASD) is associated with repetitive and stereotyped behaviour, suggesting that cognitive flexibility may be deficient in ASD. A central, yet not examined aspect to understand possible deficits in flexible behaviour in ASD relates (i) to the role of working memory and (ii) to neurophysiological mechanisms underlying behavioural modulations. We analysed behavioural and neurophysiological (EEG) correlates of cognitive flexibility using a task-switching paradigm with and without working memory load in adolescents with ASD and typically developing controls (TD). Adolescents with ASD versus TD show similar performance in task switching with no memory load, indicating that 'pure' cognitive flexibility is not in deficit in adolescent ASD. However performance during task repetition decreases with increasing memory load. Neurophysiological data reflect the pattern of behavioural effects, showing modulations in P2 and P3 event-related potentials. Working memory demands affect repetitive behaviour while processes of cognitive flexibility are unaffected. Effects emerge due to deficits in preparatory attentional processes and deficits in task rule activation, organisation and implementation of task sets when repetitive behaviour is concerned. It may be speculated that the habitual response mode in ASD (i.e. repetitive behaviour) is particularly vulnerable to additional demands on executive control processes.

  8. Solar Alpha Rotary Joint Anomaly: The Materials and Processes Perspective

    NASA Technical Reports Server (NTRS)

    Basta, Erin A.; Dasgupta, Rijib; Figert, John; Jerman, Greg; Wright, Clara; Petrakis, Dennis; Golden, Johnny L.

    2009-01-01

    This slide presentation reviews the anomaly discovered on the Solar Alpha Rotary Joint (SARJ). This anomaly was discovered when the SARJ mechanism produced anomalous telemetry and noticeable vibrations. Metallic debris was discovered throughout the vicinity of the mechanism. Samples were taken from the SARJ, and the findings of the analysis are discussed.

  9. Behind the Mpemba paradox

    PubMed Central

    Sun, Chang Qing

    2015-01-01

    Mpemba paradox results from hydrogen-bond anomalous relaxation. Heating stretches the O:H nonbond and shortens the H‒O bond via Coulomb coupling; cooling reverses this process to emit heat at a rate depending on its initial storage. Skin ultra-low mass density raises the thermal diffusivity and favors outward heat flow from the liquid. PMID:27227000

  10. Scaled Brownian motion: a paradoxical process with a time dependent diffusivity for the description of anomalous diffusion.

    PubMed

    Jeon, Jae-Hyung; Chechkin, Aleksei V; Metzler, Ralf

    2014-08-14

    Anomalous diffusion is frequently described by scaled Brownian motion (SBM), a Gaussian process with a power-law time dependent diffusion coefficient. Its mean squared displacement is 〈x(2)(t)〉 ≃ 2K(t)t with K(t) ≃ t(α-1) for 0 < α < 2. SBM may provide a seemingly adequate description in the case of unbounded diffusion, for which its probability density function coincides with that of fractional Brownian motion. Here we show that free SBM is weakly non-ergodic but does not exhibit a significant amplitude scatter of the time averaged mean squared displacement. More severely, we demonstrate that under confinement, the dynamics encoded by SBM is fundamentally different from both fractional Brownian motion and continuous time random walks. SBM is highly non-stationary and cannot provide a physical description for particles in a thermalised stationary system. Our findings have direct impact on the modelling of single particle tracking experiments, in particular, under confinement inside cellular compartments or when optical tweezers tracking methods are used.

  11. Limits on Spin-independent Couplings of Light Dark Matter WIMPs with a p-type Point-contact Germanium Detector

    NASA Astrophysics Data System (ADS)

    Lin, S. T.; Wong, H. T.

    New limits on spin-independent WIMP-nucleon coupling using 39.5 kg-days of data taken with a p-type point-contact germanium detector with fiducial mass of 840 g at the Kuo-Sheng Reactor Neutrino Laboratory (KSNL) is presented. Charactering and understanding the anomalous surface behaviour is of particular significance to this study. The slow rise-time of surface events is identified via software pulse shape analysis techniques. In addition, the signal-retaining and background-rejecting efficiencies are implied to clarify the actual bulk and surface events in the mixed regime at sub-keV range. Both efficiencies are evaluated with calibration sources and a novel n-type point-contact germanium detector. Efficiencies-corrected background spectra from the low-background facility at KSNL are derived. Part of the parameter space in cross-section versus WIMP-mass is probed and excluded.

  12. Intrinsic properties of high-spin band structures in triaxial nuclei

    NASA Astrophysics Data System (ADS)

    Jehangir, S.; Bhat, G. H.; Sheikh, J. A.; Palit, R.; Ganai, P. A.

    2017-12-01

    The band structures of 68,70Ge, 128,130,132,134Ce and 132,134,136,138Nd are investigated using the triaxial projected shell model (TPSM) approach. These nuclei depict forking of the ground-state band into several s-bands and in some cases, both the lowest two observed s-bands depict neutron or proton character. It was discussed in our earlier work that this anomalous behaviour can be explained by considering γ-bands based on two-quasiparticle configurations. As the parent band and the γ-band built on it have the same intrinsic structure, g-factors of the two bands are expected to be similar. In the present work, we have undertaken a detailed investigation of g-factors for the excited band structures of the studied nuclei and the available data for a few high-spin states are shown to be in fair agreement with the predicted values.

  13. Hafnium—an optical hydrogen sensor spanning six orders in pressure

    PubMed Central

    Boelsma, C.; Bannenberg, L. J.; van Setten, M. J.; Steinke, N.-J.; van Well, A. A.; Dam, B.

    2017-01-01

    Hydrogen detection is essential for its implementation as an energy vector. So far, palladium is considered to be the most effective hydrogen sensing material. Here we show that palladium-capped hafnium thin films show a highly reproducible change in optical transmission in response to a hydrogen exposure ranging over six orders of magnitude in pressure. The optical signal is hysteresis-free within this range, which includes a transition between two structural phases. A temperature change results in a uniform shift of the optical signal. This, to our knowledge unique, feature facilitates the sensor calibration and suggests a constant hydrogenation enthalpy. In addition, it suggests an anomalously steep increase of the entropy with the hydrogen/metal ratio that cannot be explained on the basis of a classical solid solution model. The optical behaviour as a function of its hydrogen content makes hafnium well-suited for use as a hydrogen detection material. PMID:28580959

  14. Capacitance of carbon-based electrical double-layer capacitors.

    PubMed

    Ji, Hengxing; Zhao, Xin; Qiao, Zhenhua; Jung, Jeil; Zhu, Yanwu; Lu, Yalin; Zhang, Li Li; MacDonald, Allan H; Ruoff, Rodney S

    2014-01-01

    Experimental electrical double-layer capacitances of porous carbon electrodes fall below ideal values, thus limiting the practical energy densities of carbon-based electrical double-layer capacitors. Here we investigate the origin of this behaviour by measuring the electrical double-layer capacitance in one to five-layer graphene. We find that the capacitances are suppressed near neutrality, and are anomalously enhanced for thicknesses below a few layers. We attribute the first effect to quantum capacitance effects near the point of zero charge, and the second to correlations between electrons in the graphene sheet and ions in the electrolyte. The large capacitance values imply gravimetric energy storage densities in the single-layer graphene limit that are comparable to those of batteries. We anticipate that these results shed light on developing new theoretical models in understanding the electrical double-layer capacitance of carbon electrodes, and on opening up new strategies for improving the energy density of carbon-based capacitors.

  15. Synthesis and characterization of biopolymer protected zinc sulphide nanoparticles

    NASA Astrophysics Data System (ADS)

    Senapati, U. S.; Sarkar, D.

    2015-09-01

    Zinc sulphide (ZnS) nanoparticles are prepared by a simple, economic and green synthesis route. X-ray diffraction patterns confirm zinc blend structure. ZnS formation is confirmed through chemical analysis by energy dispersive analysis of X-rays. Transmission electron microscopy reveals formation of nanosize with dimension in the range of 8-2 nm. Band gap of the nanocrystals is found to lie in the range of 4.51-4.65 eV. Photoluminescence study indicate defect like vacancies. The growth mechanism of ZnS nanoparticles is discussed with the help of Fourier transform infrared spectroscopy and thermogravimetric analysis. The materials show high dielectric constant compared to its bulk counterpart. The dielectric loss of the samples shows anomalous behaviour. The frequency dependent A.C. conductivity of the samples is discussed both in high and low frequency regimes. Current-voltage (I-V) characteristic performed under dark and under illumination, shows excellent light response of the material.

  16. Observation of unusual topological surface states in half-Heusler compounds LnPtBi (Ln=Lu, Y)

    DOE PAGES

    Liu, Z. K.; Yang, L. X.; Wu, S. -C.; ...

    2016-09-27

    Topological quantum materials represent a new class of matter with both exotic physical phenomena and novel application potentials. Many Heusler compounds, which exhibit rich emergent properties such as unusual magnetism, superconductivity and heavy fermion behaviour, have been predicted to host non-trivial topological electronic structures. The coexistence of topological order and other unusual properties makes Heusler materials ideal platform to search for new topological quantum phases (such as quantum anomalous Hall insulator and topological superconductor). By carrying out angle-resolved photoemission spectroscopy and ab initio calculations on rare-earth half-Heusler compounds LnPtBi (Ln=Lu, Y), we directly observe the unusual topological surface states onmore » these materials, establishing them as first members with non-trivial topological electronic structure in this class of materials. Moreover, as LnPtBi compounds are non-centrosymmetric superconductors, our discovery further highlights them as promising candidates of topological superconductors.« less

  17. Observation of unusual topological surface states in half-Heusler compounds LnPtBi (Ln=Lu, Y)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liu, Z. K.; Yang, L. X.; Wu, S. -C.

    Topological quantum materials represent a new class of matter with both exotic physical phenomena and novel application potentials. Many Heusler compounds, which exhibit rich emergent properties such as unusual magnetism, superconductivity and heavy fermion behaviour, have been predicted to host non-trivial topological electronic structures. The coexistence of topological order and other unusual properties makes Heusler materials ideal platform to search for new topological quantum phases (such as quantum anomalous Hall insulator and topological superconductor). By carrying out angle-resolved photoemission spectroscopy and ab initio calculations on rare-earth half-Heusler compounds LnPtBi (Ln=Lu, Y), we directly observe the unusual topological surface states onmore » these materials, establishing them as first members with non-trivial topological electronic structure in this class of materials. Moreover, as LnPtBi compounds are non-centrosymmetric superconductors, our discovery further highlights them as promising candidates of topological superconductors.« less

  18. From Affective Experience to Motivated Action: Tracking Reward-Seeking and Punishment-Avoidant Behaviour in Real-Life

    PubMed Central

    Wichers, Marieke; Kasanova, Zuzana; Bakker, Jindra; Thiery, Evert; Derom, Catherine; Jacobs, Nele; van Os, Jim

    2015-01-01

    Many of the decisions and actions in everyday life result from implicit learning processes. Important to psychopathology are, for example, implicit reward-seeking and punishment-avoidant learning processes. It is known that when specific actions get associated with a rewarding experience, such as positive emotions, that this will increase the likelihood that an organism will engage in similar actions in the future. Similarly, when actions get associated with punishing experiences, such as negative emotions, this may reduce the likelihood that the organism will engage in similar actions in the future. This study examines whether we can observe these implicit processes prospectively in the flow of daily life. If such processes take place then we expect that current behaviour can be predicted by how similar behaviour was experienced (in terms of positive and negative affect) at previous measurement moments. This was examined in a sample of 621 female individuals that had participated in an Experience Sampling data collection. Measures of affect and behaviour were collected at 10 semi-random moments of the day for 5 consecutive days. It was examined whether affective experience that was paired with certain behaviours (physical activity and social context) at previous measurements modified the likelihood to show similar behaviours at next measurement moments. Analyses were performed both at the level of observations (a time scale with units of ± 90 min) and at day level (a time scale with units of 24 h). As expected, we found that affect indeed moderated the extent to which previous behaviour predicted similar behaviour later in time, at both beep- and day-level. This study showed that it is feasible to track reward-seeking and punishment-avoidant behaviour prospectively in humans in the flow of daily life. This opens up a new toolbox to examine processes determining goal-oriented behaviour in relation to psychopathology in humans. PMID:26087323

  19. From Affective Experience to Motivated Action: Tracking Reward-Seeking and Punishment-Avoidant Behaviour in Real-Life.

    PubMed

    Wichers, Marieke; Kasanova, Zuzana; Bakker, Jindra; Thiery, Evert; Derom, Catherine; Jacobs, Nele; van Os, Jim

    2015-01-01

    Many of the decisions and actions in everyday life result from implicit learning processes. Important to psychopathology are, for example, implicit reward-seeking and punishment-avoidant learning processes. It is known that when specific actions get associated with a rewarding experience, such as positive emotions, that this will increase the likelihood that an organism will engage in similar actions in the future. Similarly, when actions get associated with punishing experiences, such as negative emotions, this may reduce the likelihood that the organism will engage in similar actions in the future. This study examines whether we can observe these implicit processes prospectively in the flow of daily life. If such processes take place then we expect that current behaviour can be predicted by how similar behaviour was experienced (in terms of positive and negative affect) at previous measurement moments. This was examined in a sample of 621 female individuals that had participated in an Experience Sampling data collection. Measures of affect and behaviour were collected at 10 semi-random moments of the day for 5 consecutive days. It was examined whether affective experience that was paired with certain behaviours (physical activity and social context) at previous measurements modified the likelihood to show similar behaviours at next measurement moments. Analyses were performed both at the level of observations (a time scale with units of ± 90 min) and at day level (a time scale with units of 24 h). As expected, we found that affect indeed moderated the extent to which previous behaviour predicted similar behaviour later in time, at both beep- and day-level. This study showed that it is feasible to track reward-seeking and punishment-avoidant behaviour prospectively in humans in the flow of daily life. This opens up a new toolbox to examine processes determining goal-oriented behaviour in relation to psychopathology in humans.

  20. Time delay and noise explaining the behaviour of the cell growth in fermentation process

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ayuobi, Tawfiqullah; Rosli, Norhayati; Bahar, Arifah

    2015-02-03

    This paper proposes to investigate the interplay between time delay and external noise in explaining the behaviour of the microbial growth in batch fermentation process. Time delay and noise are modelled jointly via stochastic delay differential equations (SDDEs). The typical behaviour of cell concentration in batch fermentation process under this model is investigated. Milstein scheme is applied for solving this model numerically. Simulation results illustrate the effects of time delay and external noise in explaining the lag and stationary phases, respectively for the cell growth of fermentation process.

  1. Time delay and noise explaining the behaviour of the cell growth in fermentation process

    NASA Astrophysics Data System (ADS)

    Ayuobi, Tawfiqullah; Rosli, Norhayati; Bahar, Arifah; Salleh, Madihah Md

    2015-02-01

    This paper proposes to investigate the interplay between time delay and external noise in explaining the behaviour of the microbial growth in batch fermentation process. Time delay and noise are modelled jointly via stochastic delay differential equations (SDDEs). The typical behaviour of cell concentration in batch fermentation process under this model is investigated. Milstein scheme is applied for solving this model numerically. Simulation results illustrate the effects of time delay and external noise in explaining the lag and stationary phases, respectively for the cell growth of fermentation process.

  2. Prenatal androgen exposure alters girls' responses to information indicating gender-appropriate behaviour

    PubMed Central

    Hines, Melissa; Pasterski, Vickie; Spencer, Debra; Neufeld, Sharon; Patalay, Praveetha; Hindmarsh, Peter C.; Hughes, Ieuan A.; Acerini, Carlo L.

    2016-01-01

    Individual variability in human gender-related behaviour is influenced by many factors, including androgen exposure prenatally, as well as self-socialization and socialization by others postnatally. Many studies have looked at these types of influences in isolation, but little is known about how they work together. Here, we report that girls exposed to high concentrations of androgens prenatally, because they have the genetic condition congenital adrenal hyperplasia, show changes in processes related to self-socialization of gender-related behaviour. Specifically, they are less responsive than other girls to information that particular objects are for girls and they show reduced imitation of female models choosing particular objects. These findings suggest that prenatal androgen exposure may influence subsequent gender-related behaviours, including object (toy) choices, in part by changing processes involved in the self-socialization of gendered behaviour, rather than only by inducing permanent changes in the brain during early development. In addition, the findings suggest that some of the behavioural effects of prenatal androgen exposure might be subject to alteration by postnatal socialization processes. The findings also suggest a previously unknown influence of early androgen exposure on later processes involved in self-socialization of gender-related behaviour, and thus expand understanding of the developmental systems regulating human gender development. PMID:26833843

  3. Prenatal androgen exposure alters girls' responses to information indicating gender-appropriate behaviour.

    PubMed

    Hines, Melissa; Pasterski, Vickie; Spencer, Debra; Neufeld, Sharon; Patalay, Praveetha; Hindmarsh, Peter C; Hughes, Ieuan A; Acerini, Carlo L

    2016-02-19

    Individual variability in human gender-related behaviour is influenced by many factors, including androgen exposure prenatally, as well as self-socialization and socialization by others postnatally. Many studies have looked at these types of influences in isolation, but little is known about how they work together. Here, we report that girls exposed to high concentrations of androgens prenatally, because they have the genetic condition congenital adrenal hyperplasia, show changes in processes related to self-socialization of gender-related behaviour. Specifically, they are less responsive than other girls to information that particular objects are for girls and they show reduced imitation of female models choosing particular objects. These findings suggest that prenatal androgen exposure may influence subsequent gender-related behaviours, including object (toy) choices, in part by changing processes involved in the self-socialization of gendered behaviour, rather than only by inducing permanent changes in the brain during early development. In addition, the findings suggest that some of the behavioural effects of prenatal androgen exposure might be subject to alteration by postnatal socialization processes. The findings also suggest a previously unknown influence of early androgen exposure on later processes involved in self-socialization of gender-related behaviour, and thus expand understanding of the developmental systems regulating human gender development. © 2016 The Author(s).

  4. The Relationship between Sensory Processing Difficulties and Behaviour in Children Aged 5-9 Who Are at Risk of Developing Conduct Disorder

    ERIC Educational Resources Information Center

    Fox, Cara; Snow, Pamela C.; Holland, Kerry

    2014-01-01

    Behavioural problems in childhood are common, with significant and wide-ranging implications for individuals, families and the community. There is some evidence that sensory processing difficulties are associated with behavioural problems in children with disabilities such as autism spectrum disorders (ASDs) and attention-deficit/hyperactivity…

  5. Do Social Information-Processing Models Explain Aggressive Behaviour by Children with Mild Intellectual Disabilities in Residential Care?

    ERIC Educational Resources Information Center

    van Nieuwenhuijzen, M.; de Castro, B. O.; van der Valk, I.; Wijnroks, L.; Vermeer, A.; Matthys, W.

    2006-01-01

    Background: This study aimed to examine whether the social information-processing model (SIP model) applies to aggressive behaviour by children with mild intellectual disabilities (MID). The response-decision element of SIP was expected to be unnecessary to explain aggressive behaviour in these children, and SIP was expected to mediate the…

  6. Solution of a modified fractional diffusion equation

    NASA Astrophysics Data System (ADS)

    Langlands, T. A. M.

    2006-07-01

    Recently, a modified fractional diffusion equation has been proposed [I. Sokolov, J. Klafter, From diffusion to anomalous diffusion: a century after Einstein's brownian motion, Chaos 15 (2005) 026103; A.V. Chechkin, R. Gorenflo, I.M. Sokolov, V.Yu. Gonchar, Distributed order time fractional diffusion equation, Frac. Calc. Appl. Anal. 6 (3) (2003) 259279; I.M. Sokolov, A.V. Checkin, J. Klafter, Distributed-order fractional kinetics, Acta. Phys. Pol. B 35 (2004) 1323.] for describing processes that become less anomalous as time progresses by the inclusion of a second fractional time derivative acting on the diffusion term. In this letter we give the solution of the modified equation on an infinite domain. In contrast to the solution of the traditional fractional diffusion equation, the solution of the modified equation requires an infinite series of Fox functions instead of a single Fox function.

  7. Observation of an anomalous decoherence effect in a quantum bath at room temperature

    PubMed Central

    Huang, Pu; Kong, Xi; Zhao, Nan; Shi, Fazhan; Wang, Pengfei; Rong, Xing; Liu, Ren-Bao; Du, Jiangfeng

    2011-01-01

    The decoherence of quantum objects is a critical issue in quantum science and technology. It is generally believed that stronger noise causes faster decoherence. Strikingly, recent theoretical work suggests that under certain conditions, the opposite is true for spins in quantum baths. Here we report an experimental observation of an anomalous decoherence effect for the electron spin-1 of a nitrogen-vacancy centre in high-purity diamond at room temperature. We demonstrate that, under dynamical decoupling, the double-transition can have longer coherence time than the single-transition even though the former couples to the nuclear spin bath as twice strongly as the latter does. The excellent agreement between the experimental and theoretical results confirms the controllability of the weakly coupled nuclear spins in the bath, which is useful in quantum information processing and quantum metrology. PMID:22146389

  8. Fractional Brownian motion with a reflecting wall.

    PubMed

    Wada, Alexander H O; Vojta, Thomas

    2018-02-01

    Fractional Brownian motion, a stochastic process with long-time correlations between its increments, is a prototypical model for anomalous diffusion. We analyze fractional Brownian motion in the presence of a reflecting wall by means of Monte Carlo simulations. Whereas the mean-square displacement of the particle shows the expected anomalous diffusion behavior 〈x^{2}〉∼t^{α}, the interplay between the geometric confinement and the long-time memory leads to a highly non-Gaussian probability density function with a power-law singularity at the barrier. In the superdiffusive case α>1, the particles accumulate at the barrier leading to a divergence of the probability density. For subdiffusion α<1, in contrast, the probability density is depleted close to the barrier. We discuss implications of these findings, in particular, for applications that are dominated by rare events.

  9. Anomalous pressure dependence of thermal conductivities of large mass ratio compounds

    DOE PAGES

    Lindsay, Lucas R; Broido, David A.; Carrete, Jesus; ...

    2015-03-27

    The lattice thermal conductivities (k) of binary compound materials are examined as a function of hydrostatic pressure P using a first-principles approach. Compound materials with relatively small mass ratios, such as MgO, show an increase in k with P, consistent with measurements. Conversely, compounds with large mass ratios (e.g., BSb, BAs, BeTe, BeSe) exhibit decreasing with increasing P, a behavior that cannot be understood using simple theories of k. This anomalous P dependence of k arises from the fundamentally different nature of the intrinsic scattering processes for heat-carrying acoustic phonons in large mass ratio compounds compared to those with smallmore » mass ratios. We find this work demonstrates the power of first principles methods for thermal properties and advances the understanding of thermal transport in non-metals.« less

  10. Pinning down electroweak dipole operators of the top quark

    DOE PAGES

    Schulze, Markus; Soreq, Yotam

    2016-08-19

    Here, we consider hadronic top quark pair production and pair production in association with a photon or a Z boson to probe electroweak dipole couplings in tb¯W, tt¯γ, and tt¯Z interactions. We demonstrate how measurements of these processes at the 13 TeV LHC can be combined to disentangle and constrain anomalous dipole operators. The construction of cross section ratios allows us to significantly reduce various uncertainties and exploit orthogonal sensitivity between the tt¯γ and tt¯Z couplings. In addition, we show that angular correlations in tt¯ production can be used to constrain the remaining tb¯W dipole operator. Our approach yields excellentmore » sensitivity to the anomalous couplings and can be a further step toward precise and direct measurements of the top quark electroweak interactions.« less

  11. Fractional motion model for characterization of anomalous diffusion from NMR signals.

    PubMed

    Fan, Yang; Gao, Jia-Hong

    2015-07-01

    Measuring molecular diffusion has been used to characterize the properties of living organisms and porous materials. NMR is able to detect the diffusion process in vivo and noninvasively. The fractional motion (FM) model is appropriate to describe anomalous diffusion phenomenon in crowded environments, such as living cells. However, no FM-based NMR theory has yet been established. Here, we present a general formulation of the FM-based NMR signal under the influence of arbitrary magnetic field gradient waveforms. An explicit analytic solution of the stretched exponential decay format for NMR signals with finite-width Stejskal-Tanner bipolar pulse magnetic field gradients is presented. Signals from a numerical simulation matched well with the theoretical prediction. In vivo diffusion-weighted brain images were acquired and analyzed using the proposed theory, and the resulting parametric maps exhibit remarkable contrasts between different brain tissues.

  12. Fractional motion model for characterization of anomalous diffusion from NMR signals

    NASA Astrophysics Data System (ADS)

    Fan, Yang; Gao, Jia-Hong

    2015-07-01

    Measuring molecular diffusion has been used to characterize the properties of living organisms and porous materials. NMR is able to detect the diffusion process in vivo and noninvasively. The fractional motion (FM) model is appropriate to describe anomalous diffusion phenomenon in crowded environments, such as living cells. However, no FM-based NMR theory has yet been established. Here, we present a general formulation of the FM-based NMR signal under the influence of arbitrary magnetic field gradient waveforms. An explicit analytic solution of the stretched exponential decay format for NMR signals with finite-width Stejskal-Tanner bipolar pulse magnetic field gradients is presented. Signals from a numerical simulation matched well with the theoretical prediction. In vivo diffusion-weighted brain images were acquired and analyzed using the proposed theory, and the resulting parametric maps exhibit remarkable contrasts between different brain tissues.

  13. The anomalous amplification of M2 tide in the Taiwan Strait

    NASA Astrophysics Data System (ADS)

    Jan, Sen; Chern, Ching-Sheng; Wang, Joe; Chao, Shenn-Yu

    2004-04-01

    The complex tidal wave propagation pattern in the Taiwan Strait invites parochialism. Along the eastern (Taiwan) boundary of the strait, the anomalous amplification of M2 tide in the middle often led to the parochial view that two tidal waves coming from both ends of the strait collide in the middle, creating wave resonance. Along the western (China) boundary, one sees a southward progressive tidal wave and hence no wave collision. To reconcile, we examine a few solutions of a numerical tidal model below. Both realistic bottom bathymetry and idealized bottom topographies are used to identify dominant mechanism leading to the complex tidal wave propagation. Our process of elimination identifies the wave reflection of southward propagating tidal wave by the deep trench in the southern strait as the true cause responsible for the complex wave propagation pattern.

  14. The suicidal process: age of onset and severity of suicidal behaviour.

    PubMed

    Thompson, Angus H; Dewa, Carolyn S; Phare, Stephanie

    2012-08-01

    The concept of the suicidal process implies a progression from behaviour of relatively low intent to completed suicide. Evidence from the literature has given rise to the speculation that the age of onset of an early form of the suicidal process may be associated with the ultimate seriousness of suicidal behaviour. This study was designed to test the hypothesis that early onset of the first stage of the suicidal process, a wish to die, is associated with increases in the ultimate position along the suicidal process dimension. Questions on the appearance and timing of suicidal process components (a death wish, ideation, plan, or attempt) were embedded in a telephone survey on mental health and addictions in the workforce. Records of those that had experienced suicidal behaviour were examined for the effects on the age of onset of the first death wish as a function of the level of severity of suicidal behaviour, gender, and depression. The findings showed that increases in suicidal intent were associated with lowered age of the first death wish. This pattern held true for depressed and non-depressed persons alike. The results support the notion that the early onset of a supposed precursor of suicidal behaviour, a death wish in this case, adds to its ability to portend more serious problem levels in later stages of life. Furthermore, mood operates independently in its association with the timing of such suicidal behaviour, suggesting that the effect of a relatively youthful appearance of a wish to die cannot be explained by early onset depression.

  15. Search for anomalous top-quark couplings with the D0 detector.

    PubMed

    Abazov, V M; Abbott, B; Abolins, M; Acharya, B S; Adams, M; Adams, T; Aguilo, E; Ahsan, M; Alexeev, G D; Alkhazov, G; Alton, A; Alverson, G; Alves, G A; Anastasoaie, M; Ancu, L S; Andeen, T; Andrieu, B; Anzelc, M S; Aoki, M; Arnoud, Y; Arov, M; Arthaud, M; Askew, A; Asman, B; Assis Jesus, A C S; Atramentov, O; Avila, C; Backusmayes, J; Badaud, F; Bagby, L; Baldin, B; Bandurin, D V; Banerjee, P; Banerjee, S; Barberis, E; Barfuss, A-F; Bargassa, P; Baringer, P; Barreto, J; Bartlett, J F; Bassler, U; Bauer, D; Beale, S; Bean, A; Begalli, M; Begel, M; Belanger-Champagne, C; Bellantoni, L; Bellavance, A; Benitez, J A; Beri, S B; Bernardi, G; Bernhard, R; Bertram, I; Besançon, M; Beuselinck, R; Bezzubov, V A; Bhat, P C; Bhatnagar, V; Blazey, G; Blekman, F; Blessing, S; Bloom, K; Boehnlein, A; Boline, D; Bolton, T A; Boos, E E; Borissov, G; Bose, T; Brandt, A; Brock, R; Brooijmans, G; Bross, A; Brown, D; Bu, X B; Buchanan, N J; Buchholz, D; Buehler, M; Buescher, V; Bunichev, V; Burdin, S; Burnett, T H; Buszello, C P; Calfayan, P; Calpas, B; Calvet, S; Cammin, J; Carrasco-Lizarraga, M A; Carrera, E; Carvalho, W; Casey, B C K; Castilla-Valdez, H; Chakrabarti, S; Chakraborty, D; Chan, K M; Chandra, A; Cheu, E; Cho, D K; Choi, S; Choudhary, B; Christofek, L; Christoudias, T; Cihangir, S; Claes, D; Clutter, J; Cooke, M; Cooper, W E; Corcoran, M; Couderc, F; Cousinou, M-C; Crépé-Renaudin, S; Cuplov, V; Cutts, D; Cwiok, M; da Motta, H; Das, A; Davies, G; De, K; de Jong, S J; De La Cruz-Burelo, E; De Oliveira Martins, C; DeVaughan, K; Déliot, F; Demarteau, M; Demina, R; Denisov, D; Denisov, S P; Desai, S; Diehl, H T; Diesburg, M; Dominguez, A; Dorland, T; Dubey, A; Dudko, L V; Duflot, L; Dugad, S R; Duggan, D; Duperrin, A; Dutt, S; Dyer, J; Dyshkant, A; Eads, M; Edmunds, D; Ellison, J; Elvira, V D; Enari, Y; Eno, S; Ermolov, P; Escalier, M; Evans, H; Evdokimov, A; Evdokimov, V N; Ferapontov, A V; Ferbel, T; Fiedler, F; Filthaut, F; Fisher, W; Fisk, H E; Fortner, M; Fox, H; Fu, S; Fuess, S; Gadfort, T; Galea, C F; Garcia, C; Garcia-Bellido, A; Gavrilov, V; Gay, P; Geist, W; Geng, W; Gerber, C E; Gershtein, Y; Gillberg, D; Ginther, G; Gómez, B; Goussiou, A; Grannis, P D; Greenlee, H; Greenwood, Z D; Gregores, E M; Grenier, G; Gris, Ph; Grivaz, J-F; Grohsjean, A; Grünendahl, S; Grünewald, M W; Guo, F; Guo, J; Gutierrez, G; Gutierrez, P; Haas, A; Hadley, N J; Haefner, P; Hagopian, S; Haley, J; Hall, I; Hall, R E; Han, L; Harder, K; Harel, A; Hauptman, J M; Hays, J; Hebbeker, T; Hedin, D; Hegeman, J G; Heinson, A P; Heintz, U; Hensel, C; Herner, K; Hesketh, G; Hildreth, M D; Hirosky, R; Hoang, T; Hobbs, J D; Hoeneisen, B; Hohlfeld, M; Hossain, S; Houben, P; Hu, Y; Hubacek, Z; Huske, N; Hynek, V; Iashvili, I; Illingworth, R; Ito, A S; Jabeen, S; Jaffré, M; Jain, S; Jakobs, K; Jarvis, C; Jesik, R; Johns, K; Johnson, C; Johnson, M; Johnston, D; Jonckheere, A; Jonsson, P; Juste, A; Kajfasz, E; Karmanov, D; Kasper, P A; Katsanos, I; Kaushik, V; Kehoe, R; Kermiche, S; Khalatyan, N; Khanov, A; Kharchilava, A; Kharzheev, Y N; Khatidze, D; Kim, T J; Kirby, M H; Kirsch, M; Klima, B; Kohli, J M; Konrath, J-P; Kozelov, A V; Kraus, J; Kuhl, T; Kumar, A; Kupco, A; Kurca, T; Kuzmin, V A; Kvita, J; Lacroix, F; Lam, D; Lammers, S; Landsberg, G; Lebrun, P; Lee, W M; Leflat, A; Lellouch, J; Li, J; Li, L; Li, Q Z; Lietti, S M; Lim, J K; Lima, J G R; Lincoln, D; Linnemann, J; Lipaev, V V; Lipton, R; Liu, Y; Liu, Z; Lobodenko, A; Lokajicek, M; Love, P; Lubatti, H J; Luna-Garcia, R; Lyon, A L; Maciel, A K A; Mackin, D; Madaras, R J; Mättig, P; Magerkurth, A; Mal, P K; Malbouisson, H B; Malik, S; Malyshev, V L; Maravin, Y; Martin, B; McCarthy, R; Meijer, M M; Melnitchouk, A; Mendoza, L; Mercadante, P G; Merkin, M; Merritt, K W; Meyer, A; Meyer, J; Mitrevski, J; Mommsen, R K; Mondal, N K; Moore, R W; Moulik, T; Muanza, G S; Mulhearn, M; Mundal, O; Mundim, L; Nagy, E; Naimuddin, M; Narain, M; Neal, H A; Negret, J P; Neustroev, P; Nilsen, H; Nogima, H; Novaes, S F; Nunnemann, T; O'Neil, D C; Obrant, G; Ochando, C; Onoprienko, D; Oshima, N; Osman, N; Osta, J; Otec, R; Otero y Garzón, G J; Owen, M; Padilla, M; Padley, P; Pangilinan, M; Parashar, N; Park, S-J; Park, S K; Parsons, J; Partridge, R; Parua, N; Patwa, A; Pawloski, G; Penning, B; Perfilov, M; Peters, K; Peters, Y; Pétroff, P; Petteni, M; Piegaia, R; Piper, J; Pleier, M-A; Podesta-Lerma, P L M; Podstavkov, V M; Pogorelov, Y; Pol, M-E; Polozov, P; Pope, B G; Popov, A V; Potter, C; da Silva, W L Prado; Prosper, H B; Protopopescu, S; Qian, J; Quadt, A; Quinn, B; Rakitine, A; Rangel, M S; Ranjan, K; Ratoff, P N; Renkel, P; Rich, P; Rijssenbeek, M; Ripp-Baudot, I; Rizatdinova, F; Robinson, S; Rodrigues, R F; Rominsky, M; Royon, C; Rubinov, P; Ruchti, R; Safronov, G; Sajot, G; Sánchez-Hernández, A; Sanders, M P; Sanghi, B; Savage, G; Sawyer, L; Scanlon, T; Schaile, D; Schamberger, R D; Scheglov, Y; Schellman, H; Schliephake, T; Schlobohm, S; Schwanenberger, C; Schwienhorst, R; Sekaric, J; Severini, H; Shabalina, E; Shamim, M; Shary, V; Shchukin, A A; Shivpuri, R K; Siccardi, V; Simak, V; Sirotenko, V; Skubic, P; Slattery, P; Smirnov, D; Snow, G R; Snow, J; Snyder, S; Söldner-Rembold, S; Sonnenschein, L; Sopczak, A; Sosebee, M; Soustruznik, K; Spurlock, B; Stark, J; Stolin, V; Stoyanova, D A; Strandberg, J; Strandberg, S; Strang, M A; Strauss, E; Strauss, M; Ströhmer, R; Strom, D; Stutte, L; Sumowidagdo, S; Svoisky, P; Sznajder, A; Tanasijczuk, A; Taylor, W; Tiller, B; Tissandier, F; Titov, M; Tokmenin, V V; Torchiani, I; Tsybychev, D; Tuchming, B; Tully, C; Tuts, P M; Unalan, R; Uvarov, L; Uvarov, S; Uzunyan, S; Vachon, B; van den Berg, P J; Van Kooten, R; van Leeuwen, W M; Varelas, N; Varnes, E W; Vasilyev, I A; Verdier, P; Vertogradov, L S; Verzocchi, M; Vilanova, D; Villeneuve-Seguier, F; Vint, P; Vokac, P; Voutilainen, M; Wagner, R; Wahl, H D; Wang, M H L S; Warchol, J; Watts, G; Wayne, M; Weber, G; Weber, M; Welty-Rieger, L; Wenger, A; Wermes, N; Wetstein, M; White, A; Wicke, D; Williams, M R J; Wilson, G W; Wimpenny, S J; Wobisch, M; Wood, D R; Wyatt, T R; Xie, Y; Xu, C; Yacoob, S; Yamada, R; Yang, W-C; Yasuda, T; Yatsunenko, Y A; Ye, Z; Yin, H; Yip, K; Yoo, H D; Youn, S W; Yu, J; Zeitnitz, C; Zelitch, S; Zhao, T; Zhou, B; Zhu, J; Zielinski, M; Zieminska, D; Zivkovic, L; Zutshi, V; Zverev, E G

    2009-03-06

    Anomalous Wtb couplings modify the angular correlations of the top-quark decay products and change the single top-quark production cross section. We present limits on anomalous top-quark couplings by combining information from W boson helicity measurements in top-quark decays and anomalous coupling searches in the single top-quark final state. We set limits on right-handed vector couplings as well as left-handed and right-handed tensor couplings based on about 1 fb(-1) of data collected by the D0 experiment.

  16. Method for non-referential defect characterization using fractal encoding and active contours

    DOEpatents

    Gleason, Shaun S [Knoxville, TN; Sari-Sarraf, Hamed [Lubbock, TX

    2007-05-15

    A method for identification of anomalous structures, such as defects, includes the steps of providing a digital image and applying fractal encoding to identify a location of at least one anomalous portion of the image. The method does not require a reference image to identify the location of the anomalous portion. The method can further include the step of initializing an active contour based on the location information obtained from the fractal encoding step and deforming an active contour to enhance the boundary delineation of the anomalous portion.

  17. Nonlinear anomalous diffusion equation and fractal dimension: exact generalized Gaussian solution.

    PubMed

    Pedron, I T; Mendes, R S; Malacarne, L C; Lenzi, E K

    2002-04-01

    In this work we incorporate, in a unified way, two anomalous behaviors, the power law and stretched exponential ones, by considering the radial dependence of the N-dimensional nonlinear diffusion equation partial differential rho/ partial differential t=nabla.(Knablarho(nu))-nabla.(muFrho)-alpharho, where K=Dr(-theta), nu, theta, mu, and D are real parameters, F is the external force, and alpha is a time-dependent source. This equation unifies the O'Shaughnessy-Procaccia anomalous diffusion equation on fractals (nu=1) and the spherical anomalous diffusion for porous media (theta=0). An exact spherical symmetric solution of this nonlinear Fokker-Planck equation is obtained, leading to a large class of anomalous behaviors. Stationary solutions for this Fokker-Planck-like equation are also discussed by introducing an effective potential.

  18. Apparatus for responding to an anomalous change in downhole pressure

    DOEpatents

    Hall, David R.; Fox, Joe; Wilde, Tyson; Barlow, Jonathan S.

    2010-04-13

    A method of responding to an anomalous change in downhole pressure in a bore hole comprises detecting the anomalous change in downhole pressure, sending a signal along the segmented electromagnetic transmission path, receiving the signal, and performing a automated response. The anomalous change in downhole pressure is detected at a first location along a segmented electromagnetic transmission path, and the segmented electromagnetic transmission path is integrated into the tool string. The signal is received by at least one receiver in communication with the segmented electromagnetic transmission path. The automated response is performed along the tool string. Disclosed is an apparatus for responding to an anomalous change in downhole pressure in a downhole tool string, comprising a segmented electromagnetic transmission path connecting one or more receivers and at least one pressure sensor.

  19. Anomalous effects of dense matter under rotation

    NASA Astrophysics Data System (ADS)

    Huang, Xu-Guang; Nishimura, Kentaro; Yamamoto, Naoki

    2018-02-01

    We study the anomaly induced effects of dense baryonic matter under rotation. We derive the anomalous terms that account for the chiral vortical effect in the low-energy effective theory for light Nambu-Goldstone modes. The anomalous terms lead to new physical consequences, such as the anomalous Hall energy current and spontaneous generation of angular momentum in a magnetic field (or spontaneous magnetization by rotation). In particular, we show that, due to the presence of such anomalous terms, the ground state of the quantum chromodynamics (QCD) under sufficiently fast rotation becomes the "chiral soliton lattice" of neutral pions that has lower energy than the QCD vacuum and nuclear matter. We briefly discuss the possible realization of the chiral soliton lattice induced by a fast rotation in noncentral heavy ion collisions.

  20. Quasi-one-dimensional quantum anomalous Hall systems as new platforms for scalable topological quantum computation

    NASA Astrophysics Data System (ADS)

    Chen, Chui-Zhen; Xie, Ying-Ming; Liu, Jie; Lee, Patrick A.; Law, K. T.

    2018-03-01

    Quantum anomalous Hall insulator/superconductor heterostructures emerged as a competitive platform to realize topological superconductors with chiral Majorana edge states as shown in recent experiments [He et al. Science 357, 294 (2017), 10.1126/science.aag2792]. However, chiral Majorana modes, being extended, cannot be used for topological quantum computation. In this work, we show that quasi-one-dimensional quantum anomalous Hall structures exhibit a large topological regime (much larger than the two-dimensional case) which supports localized Majorana zero energy modes. The non-Abelian properties of a cross-shaped quantum anomalous Hall junction is shown explicitly by time-dependent calculations. We believe that the proposed quasi-one-dimensional quantum anomalous Hall structures can be easily fabricated for scalable topological quantum computation.

  1. Structural controls on anomalous transport in fractured porous rock

    NASA Astrophysics Data System (ADS)

    Edery, Yaniv; Geiger, Sebastian; Berkowitz, Brian

    2016-07-01

    Anomalous transport is ubiquitous in a wide range of disordered systems, notably in fractured porous formations. We quantitatively identify the structural controls on anomalous tracer transport in a model of a real fractured geological formation that was mapped in an outcrop. The transport, determined by a continuum scale mathematical model, is characterized by breakthrough curves (BTCs) that document anomalous (or "non-Fickian") transport, which is accounted for by a power law distribution of local transition times ψ>(t>) within the framework of a continuous time random walk (CTRW). We show that the determination of ψ>(t>) is related to fractures aligned approximately with the macroscopic direction of flow. We establish the dominant role of fracture alignment and assess the statistics of these fractures by determining a concentration-visitation weighted residence time histogram. We then convert the histogram to a probability density function (pdf) that coincides with the CTRW ψ>(t>) and hence anomalous transport. We show that the permeability of the geological formation hosting the fracture network has a limited effect on the anomalous nature of the transport; rather, it is the fractures transverse to the flow direction that play the major role in forming the long BTC tail associated with anomalous transport. This is a remarkable result, given the complexity of the flow field statistics as captured by concentration transitions.

  2. Geochemical prospecting for Cu mineralization in an arid terrain-central Iran

    NASA Astrophysics Data System (ADS)

    Mokhtari, Ahmad Reza; Roshani Rodsari, Parisa; Fatehi, Moslem; Shahrestani, Shahed; Pournik, Peyman

    2014-12-01

    Geochemical sampling and data processing were implemented for prospecting Cu mineralization through catchment basin approach in central Iran, Yazd province, over drainage systems in order to determine areas of interest for the detailed exploration program. The target zone, inside an area called Kalout-e-Ashrafa in Yazd province-Iran, was characterized by the collection of 107 stream sediment samples. Catchment basin modeling was conducted based on digital elevation model (DEM) and geological map of the study area. Samples were studied by univariate and multivariate statistical techniques of exploratory data analysis, classical statistical analysis and cluster analysis. The results showed that only Cu had anomalous behavior and it did not exhibit a considerable correlation with other elements. Geochemical maps were prepared for Cu and anomalous zones and separated for potential copper mineralization. It was concluded that due to especial geomorphological and geographical characteristics (smooth topography, negligible annual precipitation and insufficient thickness of silicified Cu-bearing outcrops of the area), low concentrations of Cu would be expected for the delineation of promising zones in similar trains. Using cluster analysis showed that there was a strong correlation between Ag, Sr and S. Calcium and Pb present moderate correlation with Cu. Additionally, there was a strong correlation between Zn and Li, thereby indicating a meaningful correlation with Fe, P, Ti and Mg. Aluminum, Sc and V had a correlation with Be and K. Applying threshold value according to MAD (median absolute deviation) helped us to distinguish anomalous catchments more properly. Finally, there was a significant kind of conformity among anomalous catchment basins and silicified veins and veinlets (as validating index) at the central part of the area.

  3. A Study of The Binary and Anomalous Stellar Populations in Two Intermediate-Aged Open Clusters

    NASA Astrophysics Data System (ADS)

    Mathieu, Robert D.; Milliman, Katelyn; Geller, Aaron M.; Gosnell, Natalie

    2010-08-01

    ``Anomalous'' stars, such as blue stragglers and more recently sub- subgiants, have been an enduring challenge for stellar evolution theory. It is now clear that in star clusters these systems are closely linked to the binary star populations. Furthermore, sophisticated N-body models show that stellar dynamical processes play a central role in the formation of such anomalous stars. These stars trace the interface between the classical fields of stellar evolution and stellar dynamics. We propose to expand our highly successful radial-velocity survey to include two new rich open clusters NGC 7789 (1.8 Gyr, -0.1 dex) and NGC 2506 (2.1 Gyr, -0.4 dex) as part of the WIYN Open Cluster Study (WOCS). Though these two clusters are both of intermediate age and of similar richness, they have quite different blue straggler populations. NGC 2506 has only 10 known blue stragglers, while NGC 7789 has at least 27, among the largest known populations of blue stragglers in an open cluster. Defining the hard-binary populations in these two clusters is critical for understanding the factors that determine blue straggler production rates. Our proposed observations will establish the hard- binary fraction and frequency distributions of orbital parameters (periods, eccentricities, mass-ratios, etc.) for orbital periods approaching the hard-soft boundary, and will provide a comprehensive survey of the blue stragglers and other anomalous stars, including secure cluster memberships and binary properties. These data will then form direct constraints for detailed N-body open cluster simulations from which we will study the impact of the hard-binary population on the production rates and mechanisms of blue stragglers.

  4. The self-consistent parallel electric field due to electrostatic ion-cyclotron turbulence in downward auroral-current regions of the Earth's magnetosphere. IV

    NASA Astrophysics Data System (ADS)

    Jasperse, John R.; Basu, Bamandas; Lund, Eric J.; Grossbard, Neil

    2010-06-01

    The physical processes that determine the self-consistent electric field (E∥) parallel to the magnetic field have been an unresolved problem in magnetospheric physics for over 40 years. Recently, a new multimoment fluid theory was developed for inhomogeneous, nonuniformly magnetized plasma in the guiding-center and gyrotropic approximation that includes the effect of electrostatic, turbulent, wave-particle interactions (see Jasperse et al. [Phys. Plasmas 13, 072903 (2006); Jasperse et al., Phys. Plasmas13, 112902 (2006)]). In the present paper and its companion paper [Jasperse et al., Phys. Plasmas 17, 062903 (2010)], which are intended as sequels to the earlier work, a fundamental model for downward, magnetic field-aligned (Birkeland) currents for quasisteady conditions is presented. The model includes the production of electrostatic ion-cyclotron turbulence in the long-range potential region by an electron, bump-on-tail-driven ion-cyclotron instability. Anomalous momentum transfer (anomalous resistivity) by itself is found to produce a very small contribution to E∥; however, the presence of electrostatic, ion-cyclotron turbulence has a very large effect on the altitude dependence of the entire quasisteady solution. Anomalous energy transfer (anomalous heating and cooling) modifies the density, drift, and temperature altitude profiles and hence the generalized parallel-pressure gradients and mirror forces in the electron and ion momentum-balance equations. As a result, |E∥| is enhanced by nearly a factor of 40 compared to its value when turbulence is absent. The space-averaged potential increase associated with the strong double layer at the bottom of the downward-current sheet is estimated using the FAST satellite data and the multimoment fluid theory.

  5. Interstellar and Solar System Organic Matter Preserved in Interplanetary Dust

    NASA Technical Reports Server (NTRS)

    Messenger, Scott; Nakamura-Messenger, Keiko

    2015-01-01

    Interplanetary dust particles (IDPs) collected in the Earth's stratosphere derive from collisions among asteroids and by the disruption and outgassing of short-period comets. Chondritic porous (CP) IDPs are among the most primitive Solar System materials. CP-IDPs have been linked to cometary parent bodies by their mineralogy, textures, C-content, and dynamical histories. CP-IDPs are fragile, fine-grained (less than um) assemblages of anhydrous amorphous and crystalline silicates, oxides and sulfides bound together by abundant carbonaceous material. Ancient silicate, oxide, and SiC stardust grains exhibiting highly anomalous isotopic compositions are abundant in CP-IDPs, constituting 0.01 - 1 % of the mass of the particles. The organic matter in CP-IDPs is isotopically anomalous, with enrichments in D/H reaching 50x the terrestrial SMOW value and 15N/14N ratios up to 3x terrestrial standard compositions. These anomalies are indicative of low T (10-100 K) mass fractionation in cold molecular cloud or the outermost reaches of the protosolar disk. The organic matter shows distinct morphologies, including sub-um globules, bubbly textures, featureless, and with mineral inclusions. Infrared spectroscopy and mass spectrometry studies of organic matter in IDPs reveals diverse species including aliphatic and aromatic compounds. The organic matter with the highest isotopic anomalies appears to be richer in aliphatic compounds. These materials also bear similarities and differences with primitive, isotopically anomalous organic matter in carbonaceous chondrite meteorites. The diversity of the organic chemistry, morphology, and isotopic properties in IDPs and meteorites reflects variable preservation of interstellar/primordial components and Solar System processing. One unifying feature is the presence of sub-um isotopically anomalous organic globules among all primitive materials, including IDPs, meteorites, and comet Wild-2 samples returned by the Stardust mission.

  6. Anomalous Induced Seismicity due to Hydraulic Fracturing. Case of study in the Montney Formation, Northeast British Columbia.

    NASA Astrophysics Data System (ADS)

    Longobardi, M.; Bustin, A. M. M.; Johansen, K.; Bustin, R. M.

    2017-12-01

    One of our goals is to investigate the variables and processes controlling the anomalous induced seismicity and its associated ground motions, to better understand the anomalous induced seismicity (AIS) due to hydraulic fracturing in Northeast British Columbia. Our other main objective is to optimize-completions and well design. Although the vast majority of earthquakes that occur in the world each year have natural causes, some of these earthquakes and a number of lesser magnitude seismic events are induced by human activities. The recorded induced seismicity resulting from the fluid injection during hydraulic fracturing is generally small in magnitude (< M 1). Shale gas operations in Northeast British Columbia (BC) have induced the largest recorded occurrence and magnitude of AIS because of hydraulic fracturing. Anomalous induced seismicity have been recorded in seven clusters within the Montney area, with magnitudes up to ML 4.6. Five of these clusters have been linked to hydraulic fracturing. To analyse our AIS data, we first have calculated the earthquakes hypocenters. The data was recorded on an array of real-time accelerometers. We built the array based on our modified design from the early earthquake detectors installed in BC schools for the Earthquake Early Warning System for British Columbia. We have developed a new technique for locating hypocenters and applied it to our dataset. The technique will enable near real-time event location, aiding in both mitigating induced events and adjusting completions to optimize the stimulation. Our hypocenter program assumes to consider a S wave speed, fitting the arrival times to the hypocenter, and using an "amoebae method" multivariate. We have used this method because it is well suited to minimizing of the chi-squared function of the arrival time deviation. We show some preliminary results on the Montney dataset.

  7. Absorption spectrum of a two-level atom in a bad cavity with injected squeezed vacuum

    NASA Astrophysics Data System (ADS)

    Zhou, Peng; Swain, S.

    1996-02-01

    We study the absorption spectrum of a coherently driven two-level atom interacting with a resonant cavity mode which is coupled to a broadband squeezed vacuum through its input-output mirror in the bad cavity limit. We study the modification of the two-photon correlation strength of the injected squeezed vacuum inside the cavity, and show that the equations describing probe absorption in the cavity environment are formally identical to these in free space, but with modified parameters describing the squeezed vacuum. The two photon correlations induced by the squeezed vacuum are always weaker than in free space. We pay particular attention to the spectral behaviour at line centre in the region of intermediate trength driving intensities, where anomalous spectral features such as hole-burning and dispersive profiles are displayed. These unusual spectral features are very sensitive to the squeezing phase and the Rabi frequency of the driving field. We also derive the threshold value of the Rabi frequency which gives rise to the transparency of the probe beam at the driving frequency. When the Rabi frequency is less than the threshold value, the probe beam is absorbed, whilst the probe beam is amplified (without population inversion under certain conditions) when the Rabi frequency is larger than this threshold. The anomalous spectral features all take place in the vicinity of the critical point dividing the different dynamical regimes, probe absorption and amplification, of the atomic radiation. The physical origin of the strong amplification without population inversion, and the feasibility of observing it, are discussed.

  8. Anomalous Polarized Raman Scattering and Large Circular Intensity Differential in Layered Triclinic ReS2.

    PubMed

    Zhang, Shishu; Mao, Nannan; Zhang, Na; Wu, Juanxia; Tong, Lianming; Zhang, Jin

    2017-10-24

    The Raman tensor of a crystal is the derivative of its polarizability tensor and is dependent on the symmetries of the crystal and the Raman-active vibrational mode. The intensity of a particular mode is determined by the Raman selection rule, which involves the Raman tensor and the polarization configurations. For anisotropic two-dimensional (2D) layered crystals, polarized Raman scattering has been used to reveal the crystalline orientations. However, due to its complicated Raman tensors and optical birefringence, the polarized Raman scattering of triclinic 2D crystals has not been well studied yet. Herein, we report the anomalous polarized Raman scattering of 2D layered triclinic rhenium disulfide (ReS 2 ) and show a large circular intensity differential (CID) of Raman scattering in ReS 2 of different thicknesses. The origin of CID and the anomalous behavior in polarized Raman scattering were attributed to the appearance of nonzero off-diagonal Raman tensor elements and the phase factor owing to optical birefringence. This can provide a method to identify the vertical orientation of triclinic layered materials. These findings may help to further understand the Raman scattering process in 2D materials of low symmetry and may indicate important applications in chiral recognition by using 2D materials.

  9. Cervical digit in a child

    PubMed Central

    Tong, Min-Ji; Xiang, Guang-Heng; He, Zi-Li; Xu, Hua-Zi; Tian, Nai-Feng

    2017-01-01

    Abstract Background: A “digit-like” bone is a rare developmental anomaly that is usually seen in the pelvic or thoracic regions. Such an anomaly in the cervical spine is extremely rare and few cases have been reported. We present a patient with an anomalous bone posterior to a cervical vertebra. The patient was admitted to our hospital with a gradually growing hard neck mass and esthetic complaints. Physical examination, radiographs, reconstructed computed tomography, and magnetic resonance imaging revealed a digit-like bone posterior to the cervical spine. The patient was diagnosed with a “cervical digit.” Through a posterior midline approach, the anomalous bone was excised because of its gradually increasing size and esthetic complaints. Results: Intraoperatively, the bony mass was found to have a pseudoarticulation with the spinous process of C5 (the fifth cervical vertebra). The specimen consisted of normal bone and cartilage. The child returned to a normal life postoperatively with no symptoms. There was no recurrence at the 2-year follow-up. Conclusion: A congenital cervical digit is a rare deformity. A detailed clinical workup and advanced imaging examinations are useful for diagnosing such conditions. Esthetic complaints contribute to surgical indications. This is the first cervical digit managed with surgical excision of the anomalous bone and had a favorable outcome. PMID:29390517

  10. An investigation of immune system disorder as a "marker" for anomalous dominance.

    PubMed

    Rich, D A; McKeever, W F

    1990-01-01

    Geschwind and Galaburda (1987) proposed that immune disorder (ID) susceptibility, along with left handedness and familial sinistrality (FS), is a "marker" for anomalous dominance. The theory predicts lesser left lateralization for language processes, lessened left hemisphere abilities, and enhanced right hemisphere abilities. We assessed language laterality (dichotic consonant vowel task) and performances on spatial and verbal tasks. Subjects were 128 college students. The factors of handedness, sex, FS, and immune disorder history (negative or positive) were perfectly counterbalanced. Left-handers were significantly less lateralized for language and scored lower than right-handers on the spatial tasks. Females scored lower on mental rotation than males, but performed comparably to males on the spatial relations task. The only effect of ID was by way of interaction with FS on both spatial tasks--subjects who were either negative or positive on both FS and ID status factors scored significantly higher than subjects negative for one but positive for the other factor. A speculative explanatory model for this interaction was proposed. The model incorporates the notion that FS and ID factors are comparably correlated, but in opposite directions, with hormonal factors implicated by other research as relevant for spatial ability differences. Finally, no support for the "anomalous dominance" hypothesis predictions was found.

  11. Impacts of winter NPO on subsequent winter ENSO: sensitivity to the definition of NPO index

    NASA Astrophysics Data System (ADS)

    Chen, Shangfeng; Wu, Renguang

    2018-01-01

    This study investigates the linkage between boreal winter North Pacific Oscillation (NPO) and subsequent winter El Niño-Southern Oscillation (ENSO) based on seven different NPO indices. Results show that the influence of winter NPO on the subsequent winter El Niño is sensitive to how the NPO is defined. A significant NPO-El Niño connection is obtained when the NPO-related anomalous cyclone over the subtropical North Pacific extends to near-equatorial regions. The anomalous cyclone induces warm sea surface temperature (SST) anomalies through modulating surface heat fluxes. These warm SST anomalies are able to maintain into the following spring and summer through an air-sea coupled process and in turn induce significant westerly wind anomalies over the tropical western Pacific. In contrast, the NPO-El Niño relationship is unclear when the NPO-related anomalous cyclone over the subtropical North Pacific is confined to off-equatorial regions and cannot induce significant warm SST anomalies over the subtropical North Pacific. The present study suggests that definitions of NPO should be taken into account when using NPO to predict ENSO. In particular, we recommend defining the NPO index based on the empirical orthogonal function technique over appropriate region that does not extend too far north.

  12. Modelling and simulation techniques for membrane biology.

    PubMed

    Burrage, Kevin; Hancock, John; Leier, André; Nicolau, Dan V

    2007-07-01

    One of the most important aspects of Computational Cell Biology is the understanding of the complicated dynamical processes that take place on plasma membranes. These processes are often so complicated that purely temporal models cannot always adequately capture the dynamics. On the other hand, spatial models can have large computational overheads. In this article, we review some of these issues with respect to chemistry, membrane microdomains and anomalous diffusion and discuss how to select appropriate modelling and simulation paradigms based on some or all the following aspects: discrete, continuous, stochastic, delayed and complex spatial processes.

  13. Can developmental cognitive neuroscience inform intervention for social, emotional and behavioural difficulties (SEBD)?

    PubMed Central

    Frederickson, Norah; Jones, Alice P.; Warren, Laura; Deakes, Tara; Allen, Geoff

    2013-01-01

    An initial evaluation of the utility of designing an intervention to address neuroscience-based subtyping of children who have conduct problems was undertaken in this pilot study. Drawing on the literature on callous–unemotional traits, a novel intervention programme, ‘Let's Get Smart’, was implemented in a school for children with social emotional and behavioural difficulties. A mixed-methods design was used to investigate the perspectives of staff participant-observers in the change process, alongside standardised scores on measures of pupil performance and behaviour. Both qualitative and quantitative results showed reductions in externalising behaviour and improvements in measures of hypothesised underlying cognitive and affective processes. While externalising behaviour improved across subtypes, associated changes in underlying processes differed by subtype, supporting the potential value of neuroscience-informed contributions to intervention planning. PMID:26635493

  14. Developing smartphone apps for behavioural studies: The AlcoRisk app case study.

    PubMed

    Smith, Anthony; de Salas, Kristy; Lewis, Ian; Schüz, Benjamin

    2017-08-01

    Smartphone apps have emerged as valuable research tools to sample human behaviours at their time of occurrence within natural environments. Human behaviour sampling methods, such as Ecological Momentary Assessment (EMA), aim to facilitate research that is situated in ecologically valid real world environments rather than laboratory environments. Researchers have trialled a range of EMA smartphone apps to sample human behaviours such as dieting, physical activity and smoking. Software development processes for EMA smartphones apps, however, are not widely documented with little guidance provided for the integration of complex multidisciplinary behavioural and technical fields. In this paper, the AlcoRisk app for studying alcohol consumption and risk taking tendencies is presented alongside a software development process that integrates these multidisciplinary fields. The software development process consists of three stages including requirements analysis, feature and interface design followed by app implementation. Results from a preliminary feasibility study support the efficacy of the AlcoRisk app's software development process. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Anomalous Transport in Natural Fracture Networks Induced by Tectonic Stress

    NASA Astrophysics Data System (ADS)

    Kang, P. K.; Lei, Q.; Lee, S.; Dentz, M.; Juanes, R.

    2017-12-01

    Fluid flow and transport in fractured rock controls many natural and engineered processes in the subsurface. However, characterizing flow and transport through fractured media is challenging due to the high uncertainty and large heterogeneity associated with fractured rock properties. In addition to these "static" challenges, geologic fractures are always under significant overburden stress, and changes in the stress state can lead to changes in the fracture's ability to conduct fluids. While confining stress has been shown to impact fluid flow through fractures in a fundamental way, the impact of confining stress on transportthrough fractured rock remains poorly understood. The link between anomalous (non-Fickian) transport and confining stress has been shown, only recently, at the level of a single rough fracture [1]. Here, we investigate the impact of geologic (tectonic) stress on flow and tracer transport through natural fracture networks. We model geomechanical effects in 2D fractured rock by means of a finite-discrete element method (FEMDEM) [2], which can capture the deformation of matrix blocks, reactivation of pre-existing fractures, and propagation of new cracks, upon changes in the stress field. We apply the model to a fracture network extracted from the geological map of an actual rock outcrop to obtain the aperture field at different stress conditions. We then simulate fluid flow and particle transport through the stressed fracture networks. We observe that anomalous transport emerges in response to confining stress on the fracture network, and show that the stress state is a powerful determinant of transport behavior: (1) An anisotropic stress state induces preferential flow paths through shear dilation; (2) An increase in geologic stress increases aperture heterogeneity that induces late-time tailing of particle breakthrough curves. Finally, we develop an effective transport model that captures the anomalous transport through the stressed fracture network. Our results point to a heretofore unrecognized link between geomechanics and anomalous transport in natural fractured media. [1] P. K. Kang, S. Brown, and R. Juanes, Earth and Planetary Science Letters, 454, 46-54 (2016). [2] Q. Lei, J. P. Latham, and C. F. Tsang, Computers and Geotechnics, 85, 151-176 (2017).

  16. The hydrocarbon accumulations mapping in crystalline rocks by mobile geophysical methods

    NASA Astrophysics Data System (ADS)

    Nesterenko, A.

    2013-05-01

    Sedimentary-migration origin theory of hydrocarbons dominates nowadays. However, a significant amount of hydrocarbon deposits were discovered in the crystalline rocks, which corroborates the theory of non-organic origin of hydrocarbons. During the solving of problems of oil and gas exploration in crystalline rocks and arrays so-called "direct" methods can be used. These methods include geoelectric methods of forming short-pulsed electromagnetic field (FSPEF) and vertical electric-resonance sounding (VERS) (FSPEF-VERS express-technology). Use of remote Earth sounding (RES) methods is also actual. These mobile technologies are extensively used during the exploration of hydrocarbon accumulations in crystalline rocks, including those within the Ukrainian crystalline shield. The results of explorations Four anomalous geoelectric zones of "gas condensate reservoir" type were quickly revealed as a result of reconnaissance prospecting works (Fig. 1). DTA "Obukhovychi". Anomaly was traced over a distance of 4 km. Approximate area is 12.0 km2. DTA"Korolevskaya". Preliminary established size of anomalous zone is 10.0 km2. The anomalous polarized layers of gas and gas-condensate type were determined. DTA "Olizarovskaya". Approximate size of anomaly is about 56.0 km2. This anomaly is the largest and the most intense. DTA "Druzhba". Preliminary estimated size of anomaly is 16.0 km2. Conclusions Long experience of a successful application of non-classical geoelectric methods for the solving of variety of practical tasks allow one to state their contribution to the development of a new paradigm of geophysical researches. Simultaneous usage of the remote sensing data processing and interpretation method and FSPEF and VERS technologies can essentially optimize and speed up geophysical work. References 1. S.P. Levashov. Detection and mapping of anomalies of "hydrocarbon deposit" type in the fault zones of crystalline arrays by geoelectric methods. / S.P. Levashov, N.A. Yakymchuk, I.N. Korchagin, V.V. Prilukov, J.N. Yakymchuk / / Oil. Gas. Novations. - 2011/4. - P. 10-17. Introduction. (in Russian); Fig. 1. The map of "gas condensate reservoir" type anomalous geoelectric zones on the area of human settlements Malin: 1 - a scale of the intensity of anomalous response, 2 - the zones of tectonic disturbances.

  17. Interaction of vortex ring with a stratified finite thickness interface

    NASA Astrophysics Data System (ADS)

    Advaith, S.; Manu, K. V.; Tinaikar, Aashay; Chetia, Utpal Kumar; Basu, Saptarshi

    2017-09-01

    This work experimentally investigates the dynamics of interaction between a propagating vortex ring and density stratified interface of finite thickness. The flow evolution has been quantified using a high speed shadowgraph technique and particle image velocimetry. The spatial and temporal behaviours of the vortex in the near and far field of the interface and the plume structure formed due to buoyancy are investigated systematically by varying the vortex strength (Reynolds number, Re) and the degree of stratification (Atwood number, At). Maximum penetration length (Lpmax) of the vortex ring through the interface is measured over a range of Reynolds (1350 ≤ Re ≤ 4600) and Richardson (0.1 ≤ Ri ≤ 4) numbers. It is found that for low Froude number values, the maximum penetration length varies linearly with the Froude number as in the study of Orlandi et al. ["Vortex rings descending in a stratified fluid," Phys. Fluids 10, 2819-2827 (1998)]. However, for high Reynolds and Richardson numbers (Ri), anomalous behaviour in maximum penetration is observed. The Lpmax value is used to characterize the vortex-interface interactions into non-penetrative, partially-penetrative, and extensively penetrative regimes. Flow visualization revealed the occurrence of short-wavelength instability of a plume structure, particularly in a partially penetrative regime. Fluid motion exhibits chaotic behaviour in an extensively penetrative regime. Detailed analyses of plume structure propagation are performed by measuring the plume length and plume rise. Appropriate scaling for the plume length and plume rise is derived, which allows universal collapse of the data for different flow conditions. Some information concerning the instability of the plume structure and decay of the vortex ring is obtained using proper orthogonal decomposition.

  18. Influence of functional group on the electrical transport properties of polyvinyl alcohol grafted multiwall carbon nanotube composite thick film

    NASA Astrophysics Data System (ADS)

    Kumar Das, Amit; Dharmana, Reuben; Mukherjee, Ayan; Baba, Koumei; Hatada, Ruriko; Kumar Meikap, Ajit

    2018-04-01

    We present a novel technique to obtain a higher or lower value of dielectric constant due to the variation of a functional group on the surface of multiwall carbon nanotube (MWCNTs) for a polyvinyl alcohol (PVA) grafted MWCNT system. We have prepared PVA grafted pristine and different types of functionalized (-COOH, -OH, and -NH2) MWCNT nanocomposite films. The strong interfacial interaction between the host PVA matrix and nanofiller is characterized by different experimental techniques. The frequency variation of the electrical transport properties of the composite films is investigated in a wide temperature range (303 ≤ T ≤ 413 K) and frequency range (20 Hz ≤ f ≤ 1 MHz). The dielectric constant of the amine (-NH2) functionalized MWCNT incorporated PVA film is about 2 times higher than that of the pristine MWCNT embedded PVA film. The temperature variation of the dielectric constant shows an anomalous behaviour. The modified Cole-Cole equation simulated the experimentally observed dielectric spectroscopy at high temperature. The ac conductivity of the composite films obeys the correlated barrier hopping model. The imaginary part of the electric modulus study shows the ideal Debye-type behaviour at low frequency and deviation of that at high frequency. To illustrate the impedance spectroscopy of the nanocomposite films, we have proposed an impedance based battery equivalent circuit model. The current-voltage characteristic shows hysteresis behaviour of the nanocomposite films. The trap state height for all composite films is evaluated by simulating the current density-electric field data with the Poole-Frenkel emission model. This investigation opens a new avenue for designing electronic devices with a suitable combination of cost effective soft materials.

  19. Analyzing "Real-World" Anomalous Data after Experimentation with a Virtual Laboratory

    ERIC Educational Resources Information Center

    Toth, Eva Erdosne

    2016-01-01

    Developing effective pedagogies to help students examine anomalous data is critical for the education of the next generation of scientists and engineers. By definition anomalous data do not concur with prior knowledge, theories and expectations. Such data are the common outcome of empirical investigation in hands-on laboratories (HOLs). These…

  20. Surgical management of tricuspid atresia and anomalous left brachiocephalic vein.

    PubMed

    Koutlas, T C; Wernovsky, G; Slack, M C; Weinberg, P M; Spray, T L

    1998-06-01

    An anomalous left brachiocephalic vein is an uncommon systemic venous anomaly, which usually has no clinical significance. We describe a case of tricuspid atresia with such an anomalous left brachiocephalic vein. The presence of this unusual venous anomaly had a number of implications in the surgical management of the tricuspid atresia.

  1. Responses to Anomalous Data Obtained from Repeatable Experiments in the Laboratory

    ERIC Educational Resources Information Center

    Lin, Jer-Yann

    2007-01-01

    The purpose of this study was to investigate the possible responses to anomalous data obtained from experiments that are repeatable by carrying out additional or alternative experiments in the laboratory. Based on an analysis of responses from scientists to anomalous data taken from identification experiments on the Vinland Map, it was assumed…

  2. Non-Equilibrium Thermodynamics of Transcriptional Bursts

    NASA Astrophysics Data System (ADS)

    Hernández-Lemus, Enrique

    Gene transcription or Gene Expression (GE) is the process which transforms the information encoded in DNA into a functional RNA message. It is known that GE can occur in bursts or pulses. Transcription is irregular, with strong periods of activity, interspersed by long periods of inactivity. If we consider the average behavior over millions of cells, this process appears to be continuous. But at the individual cell level, there is considerable variability, and for most genes, very little activity at any one time. Some have claimed that GE bursting can account for the high variability in gene expression occurring between cells in isogenic populations. This variability has a big impact on cell behavior and thus on phenotypic conditions and disease. In view of these facts, the development of a thermodynamic framework to study gene expression and transcriptional regulation to integrate the vast amount of molecular biophysical GE data is appealing. Application of such thermodynamic formalism is useful to observe various dissipative phenomena in GE regulatory dynamics. In this chapter we will examine at some detail the complex phenomena of transcriptional bursts (specially of a certain class of anomalous bursts) in the context of a non-equilibrium thermodynamics formalism and will make some initial comments on the relevance of some irreversible processes that may be connected to anomalous transcriptional bursts.

  3. Developing a Signature Based Safeguards Approach for the Electrorefiner and Salt Cleanup Unit Operations in Pyroprocessing Facilities

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Murphy, Chantell Lynne-Marie

    Traditional nuclear materials accounting does not work well for safeguards when applied to pyroprocessing. Alternate methods such as Signature Based Safeguards (SBS) are being investigated. The goal of SBS is real-time/near-real-time detection of anomalous events in the pyroprocessing facility as they could indicate loss of special nuclear material. In high-throughput reprocessing facilities, metric tons of separated material are processed that must be accounted for. Even with very low uncertainties of accountancy measurements (<0.1%) the uncertainty of the material balances is still greater than the desired level. Novel contributions of this work are as follows: (1) significant enhancement of SBS developmentmore » for the salt cleanup process by creating a new gas sparging process model, selecting sensors to monitor normal operation, identifying safeguards-significant off-normal scenarios, and simulating those off-normal events and generating sensor output; (2) further enhancement of SBS development for the electrorefiner by simulating off-normal events caused by changes in salt concentration and identifying which conditions lead to Pu and Cm not tracking throughout the rest of the system; and (3) new contribution in applying statistical techniques to analyze the signatures gained from these two models to help draw real-time conclusions on anomalous events.« less

  4. Persistent random walk of cells involving anomalous effects and random death

    NASA Astrophysics Data System (ADS)

    Fedotov, Sergei; Tan, Abby; Zubarev, Andrey

    2015-04-01

    The purpose of this paper is to implement a random death process into a persistent random walk model which produces sub-ballistic superdiffusion (Lévy walk). We develop a stochastic two-velocity jump model of cell motility for which the switching rate depends upon the time which the cell has spent moving in one direction. It is assumed that the switching rate is a decreasing function of residence (running) time. This assumption leads to the power law for the velocity switching time distribution. This describes the anomalous persistence of cell motility: the longer the cell moves in one direction, the smaller the switching probability to another direction becomes. We derive master equations for the cell densities with the generalized switching terms involving the tempered fractional material derivatives. We show that the random death of cells has an important implication for the transport process through tempering of the superdiffusive process. In the long-time limit we write stationary master equations in terms of exponentially truncated fractional derivatives in which the rate of death plays the role of tempering of a Lévy jump distribution. We find the upper and lower bounds for the stationary profiles corresponding to the ballistic transport and diffusion with the death-rate-dependent diffusion coefficient. Monte Carlo simulations confirm these bounds.

  5. A mediator model to predict workplace influenza vaccination behaviour--an application of the health action process approach.

    PubMed

    Ernsting, Anna; Gellert, Paul; Schneider, Michael; Lippke, Sonia

    2013-01-01

    Applying the health action process approach (HAPA) to vaccination behaviour as a single-event health behaviour to study vaccination adherence and its predictors in a worksite flu vaccination programme. A total of N = 823 employees participated in a longitudinal survey. Predictors (risk perception, self-efficacy, positive and negative outcome expectancies, intention and planning) were assessed at Time 1, and behaviour was assessed five months later at Time 2. Intention and planning were specified as mediators in a path analytical logistic regression model. Risk perception, self-efficacy and positive as well as negative outcome expectancies predicted intention (R² = .76). Intention and planning predicted subsequent behaviour, and planning mediated the relation between intention and vaccination behaviour (R² = .67). In addition, results suggested the adjustment of the theoretical model: risk perception and negative outcome expectancies showed direct effects on behaviour resulting in a significantly better model fit. Findings support the general applicability of the HAPA to vaccination behaviour and the importance of planning for translating intentions into behaviour. However, the adjusted model was superior and underlined the particular role of risk perception and negative outcome expectancies for vaccination behaviour to explain underlying mechanisms in vaccination behaviour.

  6. Anomalous fluxes in the plateau regime for a weakly turbulent, magnetically confined plasma

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Balescu, R.

    1990-09-01

    The anomalous particle and heat fluxes, together with the parallel electric current, are determined for a confined plasma in the plateau regime in the presence of weak electrostatic drift-wave turbulence. Proper account is taken of nonstationarity and of the finite ion Larmor radius (FLR). The quasineutrality of the drift-wave fluctuations imposes a consistency condition, by which the evaluation of the anomalous fluxes is closely related to the drift-wave dispersion equation. On the other hand, these fluxes are related to the thermodynamic forces via the poloidal fluxes. For the weak turbulence approximation considered here, a unified formulation of the anomalous transportmore » problem has been obtained, including all aspects of neoclassical theory. The complete set of transport coefficients is calculated and various relations between them are exhibited. It clearly appears, for instance, that the anomalous ion heat flux is a pure FLR effect that vanishes as the Larmor radius goes to zero. The Onsager symmetry is broken for anomalous transport. The Appendix is devoted to a general discussion of the concept of heat flux in turbulent plasmas.« less

  7. Predicting sugar-sweetened behaviours with theory of planned behaviour constructs: Outcome and process results from the SIPsmartER behavioural intervention

    PubMed Central

    Zoellner, Jamie M.; Porter, Kathleen J.; Chen, Yvonnes; Hedrick, Valisa E.; You, Wen; Hickman, Maja; Estabrooks, Paul A.

    2017-01-01

    Objective Guided by the theory of planned behaviour (TPB) and health literacy concepts, SIPsmartER is a six-month multicomponent intervention effective at improving SSB behaviours. Using SIPsmartER data, this study explores prediction of SSB behavioural intention (BI) and behaviour from TPB constructs using: (1) cross-sectional and prospective models and (2) 11 single-item assessments from interactive voice response (IVR) technology. Design Quasi-experimental design, including pre- and post-outcome data and repeated-measures process data of 155 intervention participants. Main Outcome Measures Validated multi-item TPB measures, single-item TPB measures, and self-reported SSB behaviours. Hypothesised relationships were investigated using correlation and multiple regression models. Results TPB constructs explained 32% of the variance cross sectionally and 20% prospectively in BI; and explained 13–20% of variance cross sectionally and 6% prospectively. Single-item scale models were significant, yet explained less variance. All IVR models predicting BI (average 21%, range 6–38%) and behaviour (average 30%, range 6–55%) were significant. Conclusion Findings are interpreted in the context of other cross-sectional, prospective and experimental TPB health and dietary studies. Findings advance experimental application of the TPB, including understanding constructs at outcome and process time points and applying theory in all intervention development, implementation and evaluation phases. PMID:28165771

  8. Interannual surface variability of the Southern Pacific Ocean in relation to the SAM pattern

    NASA Astrophysics Data System (ADS)

    Cotroneo, Yuri; Menna, Milena; Falco, Pierpaolo; Poulain, Pierre Marie

    2017-04-01

    Drifter and satellite data are used to define the response of the Pacific Sector of the Southern Ocean (PSSO) to the large scale climatic pattern (Southern Annular Mode index - SAMI) in the period 1995-2015. The SAMI, defined as the mean sea level pressure difference between the 40° S and 65°S latitudes (Marshall et al., 2003), affects the eddy activity of the Southern Ocean and consequently the large-scale zonal transport in the Antarctic Circumpolar Current (ACC; Meredith and Hoggs, 2006; Hogg et al., 2014). Drifter data were primarily corrected for the wind-induced slip and currents (Ekman), then used to estimate annual values of the Eddy Kinetic Energy (EKE) fields in bins of 2°x2° over the PSSO. Time series of the drifter EKEs were compared with the EKEs derived from altimeter data over the entire study area and with the temporal evolution of SAMI. A more quantitative evaluation of the surface eddy field response to the SAMI was performed counting the number and type (cyclonic or anticyclonic)of eddies produced in the whole PSSO and in correspondence of the Sub-Antarctic Front (SAF) and Polar Front (PF). The mean latitude of each front was determined using thermal criteria applied to a long time series of in situ XBT data collected by the Italian Antarctic Programme along the track between New Zealand and Antarctica from 1994 to 2016. Eddy counting was based on the results of the identification and tracking method performed by Chelton et al. (2011), retaining only those eddies with lifetimes of 4 weeks or longer. The drifter derived EKE shows a similar and quicker response to the SAMI variability with respect to the altimetry derived EKE; the time lag is of one year for drifters and of two years for the altimetry. Both the datasets reveal an anomalous behaviour of the EKE during the period 2003-2006. The SAMI variability induces a specific effect on the different frontal zones with changes in the number and type of eddy generated. Moreover the anomalous behaviour showed by the time series of EKEs in the period 2003-2006, is observed close to the SAF and PF as well.

  9. Highly elastic polymer solutions under shear: Polymer migration, viscoelastic instabilities, and anomalous rheology

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    MacDonald, M.J.; Muller, S.J.

    1996-12-31

    The use of highly elastic polymer solutions has been remarkably successful in elucidating the behavior of polymeric materials under flowing conditions. Here, we present the results of an extensive experimental study into the shear behavior of an athermal, dilute, binary polymer solution that is believed to be free of many of these effects. Under extended shearing, we observe the migration of polymer species: after shearing for several hundred hours, concentrations that are more than double the initial uniform value can be achieved. Although the solutions are well-described by dumbbell models in shear flows on short-time scales, theoretical predictions substantially underestimatemore » the rate of migration. Flow visualization and rheometric experiments suggest that the origin of this discrepancy could be the anomalous long-time rheology of these solutions. While these fluids display the well-known elastic instability in cone and plate flow above a critical Deborah number, extended shearing reveals that the toroidal secondary flow is eventually replaced by a purely azimuthal shearing flow. In addition, when sheared below the critical condition for the instability, the solutions exhibit a slow but reversible decay in normal stresses. The shear-induced migration of polymer species has been predicted by numerous theoretical studies. However, observations on the highly elastic polymer solutions that are most likely to show polymer migration, are complicated by a number of different physical processes that occur as a result of shearing. These phenomena, which include shear-induced phase separation, elastically-induced hydrodynamic instabilities, mixed solvent effects, shear-induced aggregation, and anomalous transient shear and normal stress behavior are often observed at times earlier than and at shear rates less than those where migration is predicted to occur; hence, the experimental detection of polymer migration has been thwarted by these other physical processes.« less

  10. Predictors of High Streamflow Events in the Fraser River Basin of British Columbia, Canada

    NASA Astrophysics Data System (ADS)

    Curry, C.

    2016-12-01

    The Fraser River basin (FRB) of British Columbia is one of the largest and most important watersheds in Western North America, and is home to a rich diversity of biological species and economic assets that depend implicitly upon its extensive riverine habitats. The hydrology of the FRB is dominated by snow accumulation and melt processes, leading to a prominent annual peak streamflow invariably occurring in June-July. However, while annual peak daily streamflow (APDF) during the spring freshet in the FRB is historically well correlated with basin-averaged, annual maximum snow water equivalent (SWEmax), there are numerous occurrences of anomalously large APDF in below- or near-normal SWEmax years, some of which have resulted in damaging floods in the region. An imperfect understanding of which other climatic factors contribute to these anomalously large APDFs complicates future projections of streamflow magnitude and frequency. We employ the Variable Infiltration Capacity (VIC) process-based hydrological model driven by both observations and an ensemble of CMIP3 climate models in an attempt to discover the proximate causes of anomalous APDF events in the FRB. At several hydrometric stations representing a range of elevations, the relative importance of a set of predictors characterizing the magnitude and timing of rainfall, snowfall, and temperature is examined within a regression framework. The results indicate that next to the magnitude of SWEmax, the rate of warming subsequent to the date of SWEmax is the most influential variable for predicting APDF magnitudes in the lower FRB. Finally, the role of large-scale climate modes of variability for APDF magnitude and timing in the basin will be briefly discussed.

  11. Simple dynamical models capturing the key features of the Central Pacific El Niño.

    PubMed

    Chen, Nan; Majda, Andrew J

    2016-10-18

    The Central Pacific El Niño (CP El Niño) has been frequently observed in recent decades. The phenomenon is characterized by an anomalous warm sea surface temperature (SST) confined to the central Pacific and has different teleconnections from the traditional El Niño. Here, simple models are developed and shown to capture the key mechanisms of the CP El Niño. The starting model involves coupled atmosphere-ocean processes that are deterministic, linear, and stable. Then, systematic strategies are developed for incorporating several major mechanisms of the CP El Niño into the coupled system. First, simple nonlinear zonal advection with no ad hoc parameterization of the background SST gradient is introduced that creates coupled nonlinear advective modes of the SST. Secondly, due to the recent multidecadal strengthening of the easterly trade wind, a stochastic parameterization of the wind bursts including a mean easterly trade wind anomaly is coupled to the simple atmosphere-ocean processes. Effective stochastic noise in the wind burst model facilitates the intermittent occurrence of the CP El Niño with realistic amplitude and duration. In addition to the anomalous warm SST in the central Pacific, other major features of the CP El Niño such as the rising branch of the anomalous Walker circulation being shifted to the central Pacific and the eastern Pacific cooling with a shallow thermocline are all captured by this simple coupled model. Importantly, the coupled model succeeds in simulating a series of CP El Niño that lasts for 5 y, which resembles the two CP El Niño episodes during 1990-1995 and 2002-2006.

  12. Hyperspectral target detection using heavy-tailed distributions

    NASA Astrophysics Data System (ADS)

    Willis, Chris J.

    2009-09-01

    One promising approach to target detection in hyperspectral imagery exploits a statistical mixture model to represent scene content at a pixel level. The process then goes on to look for pixels which are rare, when judged against the model, and marks them as anomalies. It is assumed that military targets will themselves be rare and therefore likely to be detected amongst these anomalies. For the typical assumption of multivariate Gaussianity for the mixture components, the presence of the anomalous pixels within the training data will have a deleterious effect on the quality of the model. In particular, the derivation process itself is adversely affected by the attempt to accommodate the anomalies within the mixture components. This will bias the statistics of at least some of the components away from their true values and towards the anomalies. In many cases this will result in a reduction in the detection performance and an increased false alarm rate. This paper considers the use of heavy-tailed statistical distributions within the mixture model. Such distributions are better able to account for anomalies in the training data within the tails of their distributions, and the balance of the pixels within their central masses. This means that an improved model of the majority of the pixels in the scene may be produced, ultimately leading to a better anomaly detection result. The anomaly detection techniques are examined using both synthetic data and hyperspectral imagery with injected anomalous pixels. A range of results is presented for the baseline Gaussian mixture model and for models accommodating heavy-tailed distributions, for different parameterizations of the algorithms. These include scene understanding results, anomalous pixel maps at given significance levels and Receiver Operating Characteristic curves.

  13. Multi-parameter Observations and Validation of Pre-earthquake Atmospheric Signals

    NASA Astrophysics Data System (ADS)

    Ouzounov, D.; Pulinets, S. A.; Hattori, K.; Mogi, T.; Kafatos, M.

    2014-12-01

    We are presenting the latest development in multi-sensors observations of short-term pre-earthquake phenomena preceding major earthquakes. We are exploring the potential of pre-seismic atmospheric and ionospheric signals to alert for large earthquakes. To achieve this, we start validating anomalous ionospheric /atmospheric signals in retrospective and prospective modes. The integrated satellite and terrestrial framework (ISTF) is our method for validation and is based on a joint analysis of several physical and environmental parameters (Satellite thermal infrared radiation (OLR), electron concentration in the ionosphere (GPS/TEC), VHF-bands radio waves, radon/ion activities, air temperature and seismicity patterns) that were found to be associated with earthquakes. The science rationale for multidisciplinary analysis is based on concept Lithosphere-Atmosphere-Ionosphere Coupling (LAIC) [Pulinets and Ouzounov, 2011], which explains the synergy of different geospace processes and anomalous variations, usually named short-term pre-earthquake anomalies. Our validation processes consist in two steps: (1) A continuous retrospective analysis preformed over two different regions with high seismicity- Taiwan and Japan for 2003-2009 The retrospective tests (100+ major earthquakes, M>5.9, Taiwan and Japan) show OLR anomalous behavior before all of these events with no false negatives. False alarm ratio for false positives is less then 25%. (2) Prospective testing using multiple parameters with potential for M5.5+ events. The initial testing shows systematic appearance of atmospheric anomalies in advance (days) to the M5.5+ events for Taiwan and Japan (Honshu and Hokkaido areas). Our initial prospective results suggest that our approach show a systematic appearance of atmospheric anomalies, one to several days prior to the largest earthquakes That feature could be further studied and tested for advancing the multi-sensors detection of pre-earthquake atmospheric signals.

  14. Obstinate Actions-Oriented Behaviour towards Applying Theoractive Learning: An Ontology of Educational Learning and Leadership Theories in Practice

    ERIC Educational Resources Information Center

    Rajbhandari, Mani Man Singh

    2018-01-01

    Obstinate actions-oriented behaviour is the study of learning and practicing behaviour theoractively, which is acquired from the content based, process based learning and spawning critical reflexivity to the learnt theoretical phenomena into practical actions. Obstinate actions-oriented behaviour is a multi-faceted behaviour that is generally…

  15. The coach-athlete relationship: a motivational model.

    PubMed

    Mageau, Geneviève A; Vallerand, Robert J

    2003-11-01

    The aim of this paper is to present a motivational model of the coach-athlete relationship that describes how coaches may influence athletes' motivation. In line with cognitive evaluation theory (Deci and Ryan, 1980, 1985) and the hierarchical model of intrinsic and extrinsic motivation (Vallerand, 1997, 2000), a motivational sequence is proposed where coaches' personal orientation towards coaching, the context within which they operate, and their perceptions of their athletes' behaviour and motivation influence coaches' behaviours. Also, coaches' behaviours in the form of autonomy-supportive behaviours, provision of structure and involvement have a beneficial impact on athletes' needs for autonomy, competence and relatedness, which, in turn, nurture athletes' intrinsic motivation and self-determined types of extrinsic motivation. Here, we first review coaches' autonomy-supportive behaviours. We then describe the psychological processes through which coaching behaviours have a positive influence on athletes' intrinsic and self-determined extrinsic motivation. Finally, we identify social and personality processes that determine coaching behaviours.

  16. The principle of maximal transcendentality and the four-loop collinear anomalous dimension

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dixon, Lance J.

    Here, we use the principle of maximal transcendentality and the universal nature of subleading infrared poles to extract the analytic value of the four-loop collinear anomalous dimension in planar N = 4 super-Yang-Mills theory from recent QCD results, obtainingmore » $$\\hat{g}$$$(4)\\atop{0}$$ =$-$300ζ 7$-$256ζ 2ζ 5$-$384ζ 3ζ 4. This value agrees with a previous numerical result to within 0.2%. It also provides the Regge trajectory, threshold soft anomalous dimension and rapidity anomalous dimension through four loops.« less

  17. The principle of maximal transcendentality and the four-loop collinear anomalous dimension

    DOE PAGES

    Dixon, Lance J.

    2018-01-16

    Here, we use the principle of maximal transcendentality and the universal nature of subleading infrared poles to extract the analytic value of the four-loop collinear anomalous dimension in planar N = 4 super-Yang-Mills theory from recent QCD results, obtainingmore » $$\\hat{g}$$$(4)\\atop{0}$$ =$-$300ζ 7$-$256ζ 2ζ 5$-$384ζ 3ζ 4. This value agrees with a previous numerical result to within 0.2%. It also provides the Regge trajectory, threshold soft anomalous dimension and rapidity anomalous dimension through four loops.« less

  18. Anomalous cosmic ray interaction events for investigations in the SSC and Space Station era - 'Long lived she-devil phenomena'

    NASA Technical Reports Server (NTRS)

    Takahashi, Y.

    1985-01-01

    Observational data on anomalous cosmic-ray interaction events are compiled, classified, and briefly characterized. The events are divided into three groups: those confirmed by later observation or experiment, those shown to be the result of observational or analytical error, and those still unexplained. Among the phenomena in the latter group are magnetic-monopole candidates, fractionally charged particles, massive stable particles, anomalons, proton-decay and neutron-oscillation candidates, muon bundles, narrow showers, anomalous photons, fanlike phenomena, quark-gluon-plasma candidates, and anomalous long-range delta rays.

  19. A probabilistic view of chaparral and forest fire regimes in southern California and northern Baja California

    Treesearch

    Richard A. Minnich; Ernesto Franco-Vizcaíno

    2009-01-01

    Fire suppression in industrialized countries encourages massive smoke emissions from high-intensity fires as a result of two inextricably related processes under current suppression policies: the nonrandom occurrence of vegetation fires in extreme weather states and the anomalous accumulation of spatially homogenous fuels. We propose as an organizing idea that the...

  20. Topological states of condensed matter

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wang, Jing; Zhang, Shou-Cheng

    Topological states of quantum matter have been investigated intensively in recent years in materials science and condensed matter physics. The field developed explosively largely because of the precise theoretical predictions, well-controlled materials processing, and novel characterization techniques. In this Perspective, we review recent progress in topological insulators, the quantum anomalous Hall effect, chiral topological superconductors, helical topological superconductors and Weyl semimetals.

  1. A Neurocomputational Model of the N400 and the P600 in Language Processing

    ERIC Educational Resources Information Center

    Brouwer, Harm; Crocker, Matthew W.; Venhuizen, Noortje J.; Hoeks, John C. J.

    2017-01-01

    Ten years ago, researchers using event-related brain potentials (ERPs) to study language comprehension were puzzled by what looked like a "Semantic Illusion": Semantically anomalous, but structurally well-formed sentences did not affect the N400 component--traditionally taken to reflect semantic integration--but instead produced a P600…

  2. Topological states of condensed matter

    DOE PAGES

    Wang, Jing; Zhang, Shou-Cheng

    2017-10-25

    Topological states of quantum matter have been investigated intensively in recent years in materials science and condensed matter physics. The field developed explosively largely because of the precise theoretical predictions, well-controlled materials processing, and novel characterization techniques. In this Perspective, we review recent progress in topological insulators, the quantum anomalous Hall effect, chiral topological superconductors, helical topological superconductors and Weyl semimetals.

  3. Using behavioural activation in the treatment of depression: a control theory perspective.

    PubMed

    McEvoy, P; Law, A; Bates, R; Hylton, K; Mansell, W

    2013-12-01

    Behavioural activation is an intervention that can be used to counteract the typical patterns of withdrawal, avoidance and inactivity that characterize depression. This paper examines the processes of change that may occur during behavioural activation from the perspective of control theory. Some of the key concepts that are associated with control theory are introduced and the process of change that may occur during behavioural activation is illustrated using two case studies. The case studies provide anecdotal evidence which supports the hypothesis that the effective implementation of behavioural activation may depend upon clients being able to retain or regain the sense of control that they value. The differences between a control-theory-based approach and more orthodox behavioural and cognitive approaches are highlighted and the implications of these differences are discussed. Flexible approaches that are informed by control theory, may offer a useful alternative to the more established behavioural and cognitive approaches towards behavioural activation. © 2012 John Wiley & Sons Ltd.

  4. A Method for Co-Designing Theory-Based Behaviour Change Systems for Health Promotion.

    PubMed

    Janols, Rebecka; Lindgren, Helena

    2017-01-01

    A methodology was defined and developed for designing theory-based behaviour change systems for health promotion that can be tailored to the individual. Theories from two research fields were combined with a participatory action research methodology. Two case studies applying the methodology were conducted. During and between group sessions the participants created material and designs following the behaviour change strategy themes, which were discussed, analysed and transformed into a design of a behaviour change system. Theories in behavioural change and persuasive technology guided the data collection, data analyses, and the design of a behaviour change system. The methodology has strong emphasis on the target group's participation in the design process. The different aspects brought forward related to behaviour change strategies defined in literature on persuasive technology, and the dynamics of these are associated to needs and motivation defined in literature on behaviour change. It was concluded that the methodology aids the integration of theories into a participatory action research design process, and aids the analyses and motivations of design choices.

  5. Anomalous transport in the H-mode pedestal of Alcator C-Mod discharges

    NASA Astrophysics Data System (ADS)

    Pankin, A. Y.; Hughes, J. W.; Greenwald, M. J.; Kritz, A. H.; Rafiq, T.

    2017-02-01

    Anomalous transport in the H-mode pedestal region of five Alcator C-Mod discharges, representing a collisionality scan is analyzed. The understanding of anomalous transport in the pedestal region is important for the development of a comprehensive model for the H-mode pedestal slope. In this research, a possible role of the drift resistive inertial ballooning modes (Rafiq et al 2010 Phys. Plasmas 17 082511) in the edge of Alcator C-Mod discharges is analyzed. The stability analysis, carried out using the TRANSP code, indicates that the DRIBM modes are strongly unstable in Alcator C-Mod discharges with large electron collisionality. An improved interpretive analysis of H-mode pedestal experimental data is carried out utilizing the additive flux minimization technique (Pankin et al 2013 Phys. Plasmas 20 102501) together with the guiding-center neoclassical kinetic XGC0 code. The neoclassical and neutral physics are simulated in the XGC0 code and the anomalous fluxes are computed using the additive flux minimization technique. The anomalous fluxes are reconstructed and compared with each other for the collisionality scan Alcator C-Mod discharges. It is found that the electron thermal anomalous diffusivities at the pedestal top increase with the electron collisionality. This dependence can also point to the drift resistive inertial ballooning modes as the modes that drive the anomalous transport in the plasma edge of highly collisional discharges.

  6. True Anomalous Osmosis in Multi-Solute Model Membrane Systems

    PubMed Central

    Grim, Eugene; Sollner, Karl

    1960-01-01

    The transport of liquid across charged porous membranes separating two electrolytic solutions of different composition consists of both a normal and an anomalous osmotic component. Anomalous osmosis does not occur with electroneutral membranes. Thus, with membranes which can be charged and discharged reversibly, normal osmosis can be measured with the membrane in the electroneutral state, and normal together with anomalous osmosis with the membrane in a charged state, the difference between these two effects being the true anomalous osmosis. Data are presented on the osmotic effects across an oxyhemoglobin membrane in the uncharged state at pH 6.75 and in two charged states, positive at pH 4.0 and negative at pH 10.0, in multi-solute systems with 0.2 and 0.4 osmolar solutions of a variety of electrolytes and of glucose against solutions of other solutes of the same, one-half, and twice these osmolarities. In the simpler systems the magnitude of the true anomalous osmosis can be predicted semiquantitatively by reference to appropriate single-solute systems. In isoosmolar systems with two electrolytic solutions the anomalous osmotic flow rates may reach 300 µl./cm.2 hr. and more; systems with electrolytic solutions against solutions of glucose can produce twice this rate. These fluxes are of the same order of magnitude as the liquid transport rates across such living structures as the mucosa of dog gall bladder, ileum, and urinary bladder. PMID:13708691

  7. Anomalous photoconductivity

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Korsunskii, M.I.

    1973-01-01

    Translated from Russian by E. Harnik. This book investigates the nature and properties of anomalous (negative) photoconductivity observed in specially treated (mercury-activated) amorphous selenium films. A phenomenological theory is given, some properties of long-life traps are described, and a new type of centers (s-centers or storage centers) is discussed. Preparation of anomalously photoconductive Se and possible applications are considered. (86 references) (DLC)

  8. Massive Dirac fermions in a ferromagnetic kagome metal

    NASA Astrophysics Data System (ADS)

    Ye, Linda; Kang, Mingu; Liu, Junwei; von Cube, Felix; Wicker, Christina R.; Suzuki, Takehito; Jozwiak, Chris; Bostwick, Aaron; Rotenberg, Eli; Bell, David C.; Fu, Liang; Comin, Riccardo; Checkelsky, Joseph G.

    2018-03-01

    The kagome lattice is a two-dimensional network of corner-sharing triangles that is known to host exotic quantum magnetic states. Theoretical work has predicted that kagome lattices may also host Dirac electronic states that could lead to topological and Chern insulating phases, but these states have so far not been detected in experiments. Here we study the d-electron kagome metal Fe3Sn2, which is designed to support bulk massive Dirac fermions in the presence of ferromagnetic order. We observe a temperature-independent intrinsic anomalous Hall conductivity that persists above room temperature, which is suggestive of prominent Berry curvature from the time-reversal-symmetry-breaking electronic bands of the kagome plane. Using angle-resolved photoemission spectroscopy, we observe a pair of quasi-two-dimensional Dirac cones near the Fermi level with a mass gap of 30 millielectronvolts, which correspond to massive Dirac fermions that generate Berry-curvature-induced Hall conductivity. We show that this behaviour is a consequence of the underlying symmetry properties of the bilayer kagome lattice in the ferromagnetic state and the atomic spin–orbit coupling. This work provides evidence for a ferromagnetic kagome metal and an example of emergent topological electronic properties in a correlated electron system. Our results provide insight into the recent discoveries of exotic electronic behaviour in kagome-lattice antiferromagnets and may enable lattice-model realizations of fractional topological quantum states.

  9. Neotectonic effects on sinuosity and channel migration, Belle Fourche River, Western South Dakota

    USGS Publications Warehouse

    Gomez, Basil; Marron, Donna C.

    1991-01-01

    Short-term instability in the behaviour of a small, meandering alluvial channel is identified from the relation between sinuosity and either floodplain slope or channel slope within 17 reaches along an 81-kilometre section of the Belle Fourche River in western South Dakota. In reaches 1 to 4 and 11 to 17 the channel is relatively stable and sinuosity varies inversely with channel slope. In reaches 5 to 10, sinuosity is positively related to floodplain slope. Sinuosity increases markedly in reaches 5, 6, and 7 (which are immediately downstream from a discontinuity in the long profile of the floodplain) in association with an increase in floodplain slope. Immediately upstream from the discontinuity, bankfull channel depth and sinuosity decrease and the area of the floodplain reworked by meander migration between 1939 and 1981 increases, in association with a decrease in floodplain slope. Channel behaviour in reaches 5 to 10 is best explained as a consequence of neotectonic activity, as indicated by changes in elevation recorded along geodetic survey lines that cross lineaments that may delimit the eastern boundary of the Black Hills uplift. Sinuosity acts as a barometer of the effects of neotectonic activity on alluvial channels. Initial indications of channel and floodplain instability due to neotectonic activity may be derived from evidence of anomalously active channel migration, as documented from photographic or topographic sources.

  10. How molecular motors work in the crowded environment of living cells: coexistence and efficiency of normal and anomalous transport.

    PubMed

    Goychuk, Igor; Kharchenko, Vasyl O; Metzler, Ralf

    2014-01-01

    Recent experiments reveal both passive subdiffusion of various nanoparticles and anomalous active transport of such particles by molecular motors in the molecularly crowded environment of living biological cells. Passive and active microrheology reveals that the origin of this anomalous dynamics is due to the viscoelasticity of the intracellular fluid. How do molecular motors perform in such a highly viscous, dissipative environment? Can we explain the observed co-existence of the anomalous transport of relatively large particles of 100 to 500 nm in size by kinesin motors with the normal transport of smaller particles by the same molecular motors? What is the efficiency of molecular motors in the anomalous transport regime? Here we answer these seemingly conflicting questions and consistently explain experimental findings in a generalization of the well-known continuous diffusion model for molecular motors with two conformational states in which viscoelastic effects are included.

  11. How Molecular Motors Work in the Crowded Environment of Living Cells: Coexistence and Efficiency of Normal and Anomalous Transport

    PubMed Central

    Goychuk, Igor; Kharchenko, Vasyl O.; Metzler, Ralf

    2014-01-01

    Recent experiments reveal both passive subdiffusion of various nanoparticles and anomalous active transport of such particles by molecular motors in the molecularly crowded environment of living biological cells. Passive and active microrheology reveals that the origin of this anomalous dynamics is due to the viscoelasticity of the intracellular fluid. How do molecular motors perform in such a highly viscous, dissipative environment? Can we explain the observed co-existence of the anomalous transport of relatively large particles of 100 to 500 nm in size by kinesin motors with the normal transport of smaller particles by the same molecular motors? What is the efficiency of molecular motors in the anomalous transport regime? Here we answer these seemingly conflicting questions and consistently explain experimental findings in a generalization of the well-known continuous diffusion model for molecular motors with two conformational states in which viscoelastic effects are included. PMID:24626511

  12. SAD phasing with in-house cu Ka radiation using barium as anomalous scatterer.

    PubMed

    Dhanasekaran, V; Velmurugan, D

    2011-12-01

    Phasing of lysozyme crystals using co-crystallized barium ions was performed using single-wavelength anomalous diffraction (SAD) method using Cu Ka radiation with in-house source of data collection. As the ion binding sites vary with respect to the pH of the buffer during crystallization, the highly isomorphic forms of lysozyme crystals grown at acidic and alkaline pH were used for the study. Intrinsic sulphur anomalous signal was also utilized with anomalous signal from lower occupancy ions for phasing. The study showed that to solve the structure by SAD technique, 2.8-fold data redundancy was sufficient when barium was used as an anomalous marker in the in-house copper X-ray radiation source for data collection. Therefore, co-crystallization of proteins with barium containing salt can be a powerful tool for structure determination using lab source.

  13. Simultaneous generation of high-efficiency broadband asymmetric anomalous refraction and reflection waves with few-layer anisotropic metasurface

    PubMed Central

    Li, Zhancheng; Liu, Wenwei; Cheng, Hua; Liu, Jieying; Chen, Shuqi; Tian, Jianguo

    2016-01-01

    Optical metasurfaces consisting of single-layer nanostructures have immensely promising applications in wavefront control because they can be used to arbitrarily manipulate wave phase, and polarization. However, anomalous refraction and reflection waves have not yet been simultaneously and asymmetrically generated, and the limited efficiency and bandwidth of pre-existing single-layer metasurfaces hinder their practical applications. Here, a few-layer anisotropic metasurface is presented for simultaneously generating high-efficiency broadband asymmetric anomalous refraction and reflection waves. Moreover, the normal transmission and reflection waves are low and the anomalous waves are the predominant ones, which is quite beneficial for practical applications such as beam deflectors. Our work provides an effective method of enhancing the performance of anomalous wave generation, and the asymmetric performance of the proposed metasurface shows endless possibilities in wavefront control for nanophotonics device design and optical communication applications. PMID:27762286

  14. Tunneling Anomalous and Spin Hall Effects.

    PubMed

    Matos-Abiague, A; Fabian, J

    2015-07-31

    We predict, theoretically, the existence of the anomalous Hall effect when a tunneling current flows through a tunnel junction in which only one of the electrodes is magnetic. The interfacial spin-orbit coupling present in the barrier region induces a spin-dependent momentum filtering in the directions perpendicular to the tunneling current, resulting in a skew tunneling even in the absence of impurities. This produces an anomalous Hall conductance and spin Hall currents in the nonmagnetic electrode when a bias voltage is applied across the tunneling heterojunction. If the barrier is composed of a noncentrosymmetric material, the anomalous Hall conductance and spin Hall currents become anisotropic with respect to both the magnetization and crystallographic directions, allowing us to separate this interfacial phenomenon from the bulk anomalous and spin Hall contributions. The proposed effect should be useful for proving and quantifying the interfacial spin-orbit fields in metallic and metal-semiconductor systems.

  15. The charmonium dissociation in an ''anomalous wind''

    DOE PAGES

    Sadofyev, Andrey V.; Yin, Yi

    2016-01-11

    We study the charmonium dissociation in a strongly coupled chiral plasma in the presence of magnetic field and axial charge imbalance. This type of plasma carries "anomalous flow" induced by the chiral anomaly and exhibits novel transport phenomena such as chiral magnetic effect. We found that the "anomalous flow" would modify the charmonium color screening length by using the gauge/gravity correspondence. We derive an analytical expression quantifying the "anomalous flow" experienced by a charmonium for a large class of chiral plasma with a gravity dual. We elaborate on the similarity and it qualitative difference between anomalous effects on the charmoniummore » color screening length which are model-dependent and those on the heavy quark drag force which are fixed by the second law of thermodynamics. As a result, we speculate on the possible charmonium dissociation induced by the chiral anomaly in heavy ion collisions.« less

  16. Thermally driven anomalous Hall effect transitions in FeRh

    NASA Astrophysics Data System (ADS)

    Popescu, Adrian; Rodriguez-Lopez, Pablo; Haney, Paul M.; Woods, Lilia M.

    2018-04-01

    Materials exhibiting controllable magnetic phase transitions are currently in demand for many spintronics applications. Here, we investigate from first principles the electronic structure and intrinsic anomalous Hall, spin Hall, and anomalous Nernst response properties of the FeRh metallic alloy which undergoes a thermally driven antiferromagnetic-to-ferromagnetic phase transition. We show that the energy band structures and underlying Berry curvatures have important signatures in the various Hall effects. Specifically, the suppression of the anomalous Hall and Nernst effects in the antiferromagnetic state and a sign change in the spin Hall conductivity across the transition are found. It is suggested that the FeRh can be used as a spin current detector capable of differentiating the spin Hall effect from other anomalous transverse effects. The implications of this material and its thermally driven phases as a spin current detection scheme are also discussed.

  17. Modeling anomalous radial transport in kinetic transport codes

    NASA Astrophysics Data System (ADS)

    Bodi, K.; Krasheninnikov, S. I.; Cohen, R. H.; Rognlien, T. D.

    2009-11-01

    Anomalous transport is typically the dominant component of the radial transport in magnetically confined plasmas, where the physical origin of this transport is believed to be plasma turbulence. A model is presented for anomalous transport that can be used in continuum kinetic edge codes like TEMPEST, NEO and the next-generation code being developed by the Edge Simulation Laboratory. The model can also be adapted to particle-based codes. It is demonstrated that the model with a velocity-dependent diffusion and convection terms can match a diagonal gradient-driven transport matrix as found in contemporary fluid codes, but can also include off-diagonal effects. The anomalous transport model is also combined with particle drifts and a particle/energy-conserving Krook collision operator to study possible synergistic effects with neoclassical transport. For the latter study, a velocity-independent anomalous diffusion coefficient is used to mimic the effect of long-wavelength ExB turbulence.

  18. Creep Response and Deformation Processes in Nanocluster Strengthened Ferritic Steels

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hayashi, Taisuke; Sarosi, P. M.; Schneibel, Joachim H

    2008-01-01

    There is increasing demand for oxide-dispersion-strengthened ferritic alloys that possess both high-temperature strength and irradiation resistance. Improvement of the high-temperature properties requires an understanding of the operative deformation mechanisms. In this study, the microstructures and creep properties of the oxide-dispersion-strengthened alloy 14YWT have been evaluated as a function of annealing at 1000 C for 1 hour up to 32 days. The ultra-fine initial grain size (approx. 100nm) is stable after the shortest annealing time, and even after subsequent creep at 800 C. Longer annealing periods lead to anomalous grain growth that is further enhanced following creep. Remarkably, the minimum creepmore » rate is relatively insensitive to this dramatic grain-coarsening. The creep strength is attributed to highly stable, Ti-rich nanoclusters that appear to pin the initial primary grains, and present strong obstacles to dislocation motion in the large, anomalously grown grains.« less

  19. Attention focusing and anomaly detection in systems monitoring

    NASA Technical Reports Server (NTRS)

    Doyle, Richard J.

    1994-01-01

    Any attempt to introduce automation into the monitoring of complex physical systems must start from a robust anomaly detection capability. This task is far from straightforward, for a single definition of what constitutes an anomaly is difficult to come by. In addition, to make the monitoring process efficient, and to avoid the potential for information overload on human operators, attention focusing must also be addressed. When an anomaly occurs, more often than not several sensors are affected, and the partially redundant information they provide can be confusing, particularly in a crisis situation where a response is needed quickly. The focus of this paper is a new technique for attention focusing. The technique involves reasoning about the distance between two frequency distributions, and is used to detect both anomalous system parameters and 'broken' causal dependencies. These two forms of information together isolate the locus of anomalous behavior in the system being monitored.

  20. Subwavelength nonlinear phase control and anomalous phase matching in plasmonic metasurfaces

    NASA Astrophysics Data System (ADS)

    Almeida, Euclides; Shalem, Guy; Prior, Yehiam

    2016-01-01

    Metasurfaces, and in particular those containing plasmonic-based metallic elements, constitute an attractive set of materials with a potential for replacing standard bulky optical elements. In recent years, increasing attention has been focused on their nonlinear optical properties, particularly in the context of second and third harmonic generation and beam steering by phase gratings. Here, we harness the full phase control enabled by subwavelength plasmonic elements to demonstrate a unique metasurface phase matching that is required for efficient nonlinear processes. We discuss the difference between scattering by a grating and by subwavelength phase-gradient elements. We show that for such interfaces an anomalous phase-matching condition prevails, which is the nonlinear analogue of the generalized Snell's law. The subwavelength phase control of optical nonlinearities paves the way for the design of ultrathin, flat nonlinear optical elements. We demonstrate nonlinear metasurface lenses, which act both as generators and as manipulators of the frequency-converted signal.

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