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Sample records for long-range coherence revealed

  1. Long range coherence in free electron lasers

    NASA Technical Reports Server (NTRS)

    Colson, W. B.

    1984-01-01

    The simple free electron laser (FEL) design uses a static, periodic, transverse magnetic field to undulate relativistic electrons traveling along its axis. This allows coupling to a co-propagating optical wave and results in bunching to produce coherent radiation. The advantages of the FEL are continuous tunability, operation at wavelengths ranging from centimeters to angstroms, and high efficiency resulting from the fact that the interaction region only contains light, relativistic electrons, and a magnetic field. Theoretical concepts and operational principles are discussed.

  2. Frequency multiplexed long range swept source optical coherence tomography

    PubMed Central

    Zurauskas, Mantas; Bradu, Adrian; Podoleanu, Adrian Gh.

    2013-01-01

    We present a novel swept source optical coherence tomography configuration, equipped with acousto-optic deflectors that can be used to simultaneously acquire multiple B-scans originating from different depths. The sensitivity range of the configuration is evaluated while acquiring five simultaneous B-scans. Then the configuration is employed to demonstrate long range B-scan imaging by combining two simultaneous B-scans from a mouse head sample. PMID:23760762

  3. Coherent long-range thermoelectrics in nonadiabatic driven quantum systems

    NASA Astrophysics Data System (ADS)

    Gallego-Marcos, F.; Platero, G.

    2017-02-01

    We investigate direct energy and heat transfer between two distant sites of a triple quantum dot connected to reservoirs, where one of the edge dots is driven by an ac-gate voltage. We theoretically propose how to implement heat and cooling engines mediated by long-range photoassisted transport. Additionally, we propose a simple setup to heat up coherently the two reservoirs symmetrically and a mechanism to store energy in the closed system. The present proposals can be experimentally implemented and easily controlled by tuning the external parameters.

  4. Classical investigation of long-range coherence in biological systems

    NASA Astrophysics Data System (ADS)

    Preto, Jordane

    2016-12-01

    Almost five decades ago, H. Fröhlich [H. Fröhlich, "Long-range coherence and energy storage in biological systems," Int. J. Quantum Chem. 2(5), 641-649 (1968)] reported, on a theoretical basis, that the excitation of quantum modes of vibration in contact with a thermal reservoir may lead to steady states, where under high enough rate of energy supply, only specific low-frequency modes of vibration are strongly excited. This nonlinear phenomenon was predicted to occur in biomolecular systems, which are known to exhibit complex vibrational spectral properties, especially in the terahertz frequency domain. However, since the effects of terahertz or lower-frequency modes are mainly classical at physiological temperatures, there are serious doubts that Fröhlich's quantum description can be applied to predict such a coherent behavior in a biological environment, as suggested by the author. In addition, a quantum formalism makes the phenomenon hard to investigate using realistic molecular dynamics simulations (MD) as they are usually based on the classical principles. In the current paper, we provide a general classical Hamiltonian description of a nonlinear open system composed of many degrees of freedom (biomolecular structure) excited by an external energy source. It is shown that a coherent behaviour similar to Fröhlich's effect is to be expected in the classical case for a given range of parameter values. Thus, the supplied energy is not completely thermalized but stored in a highly ordered fashion. The connection between our Hamiltonian description, carried out in the space of normal modes, and a more standard treatment in the physical space is emphasized in order to facilitate the prediction of the effect from MD simulations. It is shown how such a coherent phenomenon may induce long-range resonance effects that could be of critical importance at the biomolecular level. The present work is motivated by recent experimental evidences of long-lived excited low

  5. Classical investigation of long-range coherence in biological systems.

    PubMed

    Preto, Jordane

    2016-12-01

    Almost five decades ago, H. Fröhlich [H. Fröhlich, "Long-range coherence and energy storage in biological systems," Int. J. Quantum Chem. 2(5), 641-649 (1968)] reported, on a theoretical basis, that the excitation of quantum modes of vibration in contact with a thermal reservoir may lead to steady states, where under high enough rate of energy supply, only specific low-frequency modes of vibration are strongly excited. This nonlinear phenomenon was predicted to occur in biomolecular systems, which are known to exhibit complex vibrational spectral properties, especially in the terahertz frequency domain. However, since the effects of terahertz or lower-frequency modes are mainly classical at physiological temperatures, there are serious doubts that Fröhlich's quantum description can be applied to predict such a coherent behavior in a biological environment, as suggested by the author. In addition, a quantum formalism makes the phenomenon hard to investigate using realistic molecular dynamics simulations (MD) as they are usually based on the classical principles. In the current paper, we provide a general classical Hamiltonian description of a nonlinear open system composed of many degrees of freedom (biomolecular structure) excited by an external energy source. It is shown that a coherent behaviour similar to Fröhlich's effect is to be expected in the classical case for a given range of parameter values. Thus, the supplied energy is not completely thermalized but stored in a highly ordered fashion. The connection between our Hamiltonian description, carried out in the space of normal modes, and a more standard treatment in the physical space is emphasized in order to facilitate the prediction of the effect from MD simulations. It is shown how such a coherent phenomenon may induce long-range resonance effects that could be of critical importance at the biomolecular level. The present work is motivated by recent experimental evidences of long-lived excited low

  6. Observation of long range coherent OTR from LPA electron beams

    NASA Astrophysics Data System (ADS)

    van Tilborg, Jeroen; Lin, Chen; Nakamura, Kei; Gonsalves, Anthony; Matlis, Nicholas; Sokollik, Thomas; Shiraishi, Satomi; Schroeder, Carl; Benedetti, Carlo; Esarey, Eric; Leemans, Wim; Loasis Program Collaboration

    2011-10-01

    We report the observation of coherent optical transition radiation (COTR) from electron bunches that have propagated for up to 4 m from the exit of the laser plasma accelerator (LPA). This measurement indicates sub-percent-level slice energy spread of the LPA-produced electron beams. Transition radiation images, produced by electrons passing through two separate foils (located from the LPA at 2.3 m and 3.8 m) were recorded with a high resolution imaging system. Transition radiation in the visible wavelength regime was measured at signal levels of more than two orders of magnitude greater than expected from incoherent emission, indicating that femtosecond structure on the electron beams persisted over meter-scale propagation distances. This persistence implies an upper limit for the slice energy spread on the sub-percent level. Furthermore, for a selection of shots the coherent enhancement from the 3.8-m foil was higher than the closer 2.3-m one, consistent with dynamic changes of the bunch structure due to beam velocity bunching. Experimental results and modeling efforts will be presented. This work was supported by US DOE Contract No. DE-AC02-05CH11231.

  7. Long-range measurement of Rayleigh scatter signature beyond laser coherence length based on coherent optical frequency domain reflectometry.

    PubMed

    Ohno, Shingo; Iida, Daisuke; Toge, Kunihiro; Manabe, Tetsuya

    2016-08-22

    Long-range C-OFDR measurement of fiber Rayleigh scatter signature is described. The Rayleigh scatter signature, which is an interference pattern of backscatters from the random refractive indices in fibers, is known to be applicable to fiber identification and temperature or strain sensing by measuring its repeatability and its spectral shift. However, these applications have not been realized at ranges beyond the laser coherence length since laser phase noise degrades its repeatability. This paper proposes and demonstrates a method for analyzing the optical power spectrum of local Rayleigh backscatter to overcome the limitation imposed by laser phase noise. The measurable range and spatial performance are also investigated experimentally with respect to the remaining phase noise and noise reduction by signal averaging with the proposed method. The feasibility of Rayleigh scatter signature measurement for long-range applications is confirmed.

  8. Simultaneous loss of interlayer coherence and long-range magnetism in quasi-two-dimensional PdCrO2

    PubMed Central

    Ghannadzadeh, S.; Licciardello, S.; Arsenijević, S.; Robinson, P.; Takatsu, H.; Katsnelson, M. I.; Hussey, N. E.

    2017-01-01

    In many layered metals, coherent propagation of electronic excitations is often confined to the highly conducting planes. While strong electron correlations and/or proximity to an ordered phase are believed to be the drivers of this electron confinement, it is still not known what triggers the loss of interlayer coherence in a number of layered systems with strong magnetic fluctuations, such as cuprates. Here, we show that a definitive signature of interlayer coherence in the metallic-layered triangular antiferromagnet PdCrO2 vanishes at the Néel transition temperature. Comparison with the relevant energy scales and with the isostructural non-magnetic PdCoO2 reveals that the interlayer incoherence is driven by the growth of short-range magnetic fluctuations. This establishes a connection between long-range order and interlayer coherence in PdCrO2 and suggests that in many other low-dimensional conductors, incoherent interlayer transport also arises from the strong interaction between the (tunnelling) electrons and fluctuations of some underlying order. PMID:28406142

  9. Long-range Fourier domain optical coherence tomography of the pediatric subglottis

    PubMed Central

    Volgger, Veronika; Sharma, Giriraj K.; Jing, Joe; Peaks, Ya-Sin A.; Loy, Anthony Chin; Lazarow, Frances; Wang, Alex; Qu, Yueqiao; Su, Erica; Chen, Zhongping; Ahuja, Gurpreet S.; Wong, Brian J-F.

    2014-01-01

    Background Acquired subglottic stenosis (SGS) most commonly results from prolonged endotracheal intubation and is a diagnostic challenge in the intubated child. At present, no imaging modality allows for in vivo characterization of subglottic microanatomy to identify early signs of acquired SGS while the child remains intubated. Fourier domain optical coherence tomography (FD-OCT) is a minimally invasive, light-based imaging modality which provides high resolution, three dimensional (3D) cross-sectional images of biological tissue. We used long-range FD-OCT to image the subglottis in intubated pediatric patients undergoing minor head and neck surgical procedures in the operating room. Methods A long-range FD-OCT system and rotary optical probes (1.2 mm and 0.7 mm outer diameters) were constructed. Forty-six pediatric patients (ages 2–16 years) undergoing minor upper airway surgery (e.g. tonsillectomy, adenoidectomy) were selected for intraoperative, trans-endotracheal tube FD-OCT of the subglottis. Images were analyzed for anatomical landmarks and subepithelial histology. Volumetric image sets were rendered into virtual 3D airway models in Mimics software. Results FD-OCT was performed on 46 patients (ages 2–16 years) with no complications. Gross airway contour was visible on all 46 data sets. Twenty (43%) high-quality data sets clearly demonstrated airway anatomy (e.g., tracheal rings, cricoid, vocal folds) and layered microanatomy of the mucosa (e.g., epithelium, basement membrane, lamina propria). The remaining 26 data sets were discarded due to artifact, high signal-to-noise ratio or missing data. 3D airway models allowed for user-controlled manipulation and multiplanar airway slicing (e.g. sagittal, coronal) for visualization of OCT data at multiple anatomic levels simultaneously. Conclusions Long-range FD-OCT produces high-resolution, 3D volumetric images of the pediatric subglottis. This technology offers a safe and practical means for in vivo evaluation

  10. Coherent-interference-induced transparency based on long-range air-hole assisted subwavelength waveguides

    NASA Astrophysics Data System (ADS)

    Zhou, Wen; Huang, Xu Guang; Tan, Qilong; Liang, Yao; Lao, Jieer; Chen, Zanhui

    2014-11-01

    A novel coherent-interference-induced transparency (CIT) system consisting of two coupled and detuned double-sided-branch (DSB) filters in a long-range air-hole assisted subwavelength (LR-AHAS) waveguide has been proposed and numerically demonstrated. The resonant wavelength, maximum transmittance, full width at half maximum (FWHM) and phase dispersion of the transparent window can be effectively tuned by adjusting the detuning and phase-shift between two coupled DSB filters, and FWHM can be suppressed to as small as 1.6 nm, which is much narrower than that of an individual resonator in an LR-AHAS waveguide. The FWHMs of 3.2 nm and 5.2 nm with the corresponding group refractive indices ng of 73 and 45 have been respectively demonstrated. In addition, multiple transparent peaks with an average bandwidth of 3.6 nm and high transmittance of 0.74 can be achieved by cascading more detuned DSB filters into the system. It provides a new approach to develop tunable high-channel-count bandpass filters and optical buffers based on the LR-AHAS waveguide platform for large-scale photonic integrations.

  11. Long-Range Underwater Sound Propagation: Environmental Variability, Signal Stability and Signal Coherence

    DTIC Science & Technology

    2014-09-30

    Variability, Signal Stability and Signal Coherence Michael G. Brown Division of Applied Marine Physics Rosenstiel School of Marine and...variability on signal stability and coherence . We seek to understand the fundamental limits to signal processing imposed by ocean variability to enable...logistics of which is very simple. That field work has been partially supported by NSF. Field work has been complemented by data-driven theoretical

  12. Long-Range Underwater Sound Propagation: Environmental Variability, Signal Stability and Signal Coherence

    DTIC Science & Technology

    2013-09-30

    Variability, Signal Stability and Signal Coherence Michael G. Brown Division of Applied Marine Physics Rosenstiel School of Marine and...variability on signal stability and coherence . We seek to understand the fundamental limits to signal processing imposed by ocean variability to enable...stability parameter α or the asymptotically equivalent mode-based waveguide invariant β) of the background sound speed profile, rather than details

  13. Simple and versatile long range swept source for optical coherence tomography applications

    NASA Astrophysics Data System (ADS)

    Bräuer, Bastian; Lippok, Norman; Murdoch, Stuart G.; Vanholsbeeck, Frédérique

    2015-12-01

    We present a versatile long coherence length swept-source laser design for optical coherence tomography applications. This design consists of a polygonal spinning mirror and an optical gain chip in a modified Littman-Metcalf cavity. A narrowband intra-cavity filter is implemented through multiple passes off a diffraction grating set at grazing incidence. The key advantage of this design is that it can be readily adapted to any wavelength regions for which broadband gain chips are available. We demonstrate this by implementing sources at 1650 nm, 1550 nm, 1310 nm and 1050 nm. In particular, we present a 1310 nm swept source laser with 24 mm coherence length, 95 nm optical bandwidth, 2 kHz maximum sweep frequency and 7.5 mW average output power. These parameters make it a suitable source for the imaging of biological samples.

  14. Evidence for the existence of long-range phase coherence in the bacteriorhodopsin macromolecule

    NASA Astrophysics Data System (ADS)

    Dunne, Lawrence J.; Clark, Anthony D.; Brändas, Erkki J.

    1983-06-01

    Recent experimental evidence suggests that in the proton pump bacteriorhodopsin (BR) from Halobacterium Halobium, two protons are transported across the membrane in each photocycle. Following our coherent-state model for the visual protein rhodopsin, which has a close structural similarity to BR, we suggest the occurrence of a superfluid coherent electronic state in the BR molecule. From this we can show that the magnetic flux in BR is quantised and hence we predict that the charge of the moving ion cluster will be ±2e, and offer this as a tentative explanation of the experimental results.

  15. The primary structure of the aridicin aglycon as revealed by long-range J values

    NASA Astrophysics Data System (ADS)

    Mueller, Luciano; Jeffs, Peter W.

    The aglycon of aridicin, which is a member of the vancomycin class of antibiotics, was analyzed by utilizing J spin-spin interactions in two-dimensional NMR experiments.This unusual heptapeptide with the molecular formula C 59H 45N 7O 19Cl 4 (MW 1296.160) has a large number of quateernary carbons in aromatic side chains. For that reason most information was obtained from delayed COSY and COLOC spectra which reveal homo- and heteronuclear connectivities via long-range J couplings. The carbon-13 spectrum was assigned completely. In addition, the primary structure of the aridicin aglycon could be deduced, with the exception of the ether linkages between the side chains A, B, and C, by solely relying on J-connectivity maps.

  16. Automatic airway wall segmentation and thickness measurement for long-range optical coherence tomography images.

    PubMed

    Qi, Li; Huang, Shenghai; Heidari, Andrew E; Dai, Cuixia; Zhu, Jiang; Zhang, Xuping; Chen, Zhongping

    2015-12-28

    We present an automatic segmentation method for the delineation and quantitative thickness measurement of multiple layers in endoscopic airway optical coherence tomography (OCT) images. The boundaries of the mucosa and the sub-mucosa layers are accurately extracted using a graph-theory-based dynamic programming algorithm. The algorithm was tested with sheep airway OCT images. Quantitative thicknesses of the mucosal layers are obtained automatically for smoke inhalation injury experiments.

  17. Automatic airway wall segmentation and thickness measurement for long-range optical coherence tomography images

    PubMed Central

    Qi, Li; Huang, Shenghai; Heidari, Andrew E.; Dai, Cuixia; Zhu, Jiang; Zhang, Xuping; Chen, Zhongping

    2015-01-01

    We present an automatic segmentation method for the delineation and quantitative thickness measurement of multiple layers in endoscopic airway optical coherence tomography (OCT) images. The boundaries of the mucosa and the sub-mucosa layers are accurately extracted using a graph-theory-based dynamic programming algorithm. The algorithm was tested with sheep airway OCT images. Quantitative thicknesses of the mucosal layers are obtained automatically for smoke inhalation injury experiments. PMID:26832057

  18. Bacterial intelligence: imitation games, time-sharing, and long-range quantum coherence.

    PubMed

    Majumdar, Sarangam; Pal, Sukla

    2017-05-17

    Bacteria are far more intelligent than we can think of. They adopt different survival strategies to make their life comfortable. Researches on bacterial communication to date suggest that bacteria can communicate with each other using chemical signaling molecules as well as using ion channel mediated electrical signaling. Though in past few decades the scopes of chemical signaling have been investigated extensively, those of electrical signaling have received less attention. In this article, we present a novel perspective on time-sharing behavior, which maintains the biofilm growth under reduced nutrient supply between two distant biofilms through electrical signaling based on the experimental evidence reported by Liu et al., in 2017. In addition, following the recent work by Humphries et al. Cell 168(1):200-209, in 2017, we highlight the consequences of long range electrical signaling within biofilm communities through spatially propagating waves of potassium. Furthermore, we address the possibility of two-way cellular communication between artificial and natural cells through chemical signaling being inspired by recent experimental observation (Lentini et al. 2017) where the efficiency of artificial cells in imitating the natural cells is estimated through cellular Turing test. These three spectacular observations lead us to envisage and devise new classical and quantum views of these complex biochemical networks that have never been realized previously.

  19. Coherent control of long-range photoinduced electron transfer by stimulated X-ray Raman processes

    PubMed Central

    Dorfman, Konstantin E.; Zhang, Yu; Mukamel, Shaul

    2016-01-01

    We show that X-ray pulses resonant with selected core transitions can manipulate electron transfer (ET) in molecules with ultrafast and atomic selectivity. We present possible protocols for coherently controlling ET dynamics in donor–bridge–acceptor (DBA) systems by stimulated X-ray resonant Raman processes involving various transitions between the D, B, and A sites. Simulations presented for a Ru(II)–Co(III) model complex demonstrate how the shapes, phases and amplitudes of the X-ray pulses can be optimized to create charge on demand at selected atoms, by opening up otherwise blocked ET pathways. PMID:27559082

  20. Coherent control of long-range photoinduced electron transfer by stimulated X-ray Raman processes.

    PubMed

    Dorfman, Konstantin E; Zhang, Yu; Mukamel, Shaul

    2016-09-06

    We show that X-ray pulses resonant with selected core transitions can manipulate electron transfer (ET) in molecules with ultrafast and atomic selectivity. We present possible protocols for coherently controlling ET dynamics in donor-bridge-acceptor (DBA) systems by stimulated X-ray resonant Raman processes involving various transitions between the D, B, and A sites. Simulations presented for a Ru(II)-Co(III) model complex demonstrate how the shapes, phases and amplitudes of the X-ray pulses can be optimized to create charge on demand at selected atoms, by opening up otherwise blocked ET pathways.

  1. Robust numerical phase stabilization for long-range swept-source optical coherence tomography.

    PubMed

    Song, Shaozhen; Xu, Jingjiang; Men, Shaojie; Shen, Tueng T; Wang, Ruikang K

    2017-05-09

    A novel phase stabilization technique is demonstrated with significant improvement in the phase stability of a micro-electromechanical (MEMS) vertical cavity surface-emitting laser (VCSEL) based swept-source optical coherence tomography (SS-OCT) system. Without any requirements of hardware modifications, the new fully numerical phase stabilization technique features high tolerance to acquisition jitter, and significantly reduced budget in computational effort. We demonstrate that when measured with biological tissue, this technique enables a phase sensitivity of 89 mrad in highly scattering tissue, with image ranging distance of up to 12.5 mm at A-line scan rate of 100.3 kHz. We further compare the performances delivered by the phase-stabilization approach with conventional numerical approach for accuracy and computational efficiency. Imaging result of complex signal-based optical coherence tomography angiography (OCTA) and Doppler OCTA indicate that the proposed phase stabilization technique is robust, and efficient in improving the image contrast-to-noise ratio and extending OCTA depth range. The proposed technique can be universally applied to improve phase-stability in generic SS-OCT with different scale of scan rates without a need for special treatment. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Sperm whale long-range echolocation sounds revealed by ANTARES, a deep-sea neutrino telescope

    PubMed Central

    André, M.; Caballé, A.; van der Schaar, M.; Solsona, A.; Houégnigan, L.; Zaugg, S.; Sánchez, A. M.; Castell, J. V.; Solé, M.; Vila, F.; Djokic, D.; Adrián-Martínez, S.; Albert, A.; Anghinolfi, M.; Anton, G.; Ardid, M.; Aubert, J.-J.; Avgitas, T.; Baret, B.; Barrios-Martí, J.; Basa, S.; Bertin, V.; Biagi, S.; Bormuth, R.; Bouwhuis, M. C.; Bruijn, R.; Brunner, J.; Busto, J.; Capone, A.; Caramete, L.; Carr, J.; Celli, S.; Chiarusi, T.; Circella, M.; Coleiro, A.; Coniglione, R.; Costantini, H.; Coyle, P.; Creusot, A.; Deschamps, A.; De Bonis, G.; Distefano, C.; Di Palma, I.; Donzaud, C.; Dornic, D.; Drouhin, D.; Eberl, T.; El Bojaddaini, I.; Elsässer, D.; Enzenhöfer, A.; Fehn, K.; Felis, I.; Fusco, L. A.; Galatà, S.; Gay, P.; Geißelsöder, S.; Geyer, K.; Giordano, V.; Gleixner, A.; Glotin, H.; Gracia-Ruiz, R.; Graf, K.; Hallmann, S.; van Haren, H.; Heijboer, A. J.; Hello, Y.; Hernandez-Rey, J. J.; Hößl, J.; Hofestädt, J.; Hugon, C.; Illuminati, G.; James, C. W.; de Jong, M.; Jongen, M.; Kadler, M.; Kalekin, O.; Katz, U.; Kießling, D.; Kouchner, A.; Kreter, M.; Kreykenbohm, I.; Kulikovskiy, V.; Lachaud, C.; Lahmann, R.; Lefèvre, D.; Leonora, E.; Loucatos, S.; Marcelin, M.; Margiotta, A.; Marinelli, A.; Martínez-Mora, J. A.; Mathieu, A.; Melis, K.; Michael, T.; Migliozzi, P.; Moussa, A.; Mueller, C.; Nezri, E.; Păvălaş, G. E.; Pellegrino, C.; Perrina, C.; Piattelli, P.; Popa, V.; Pradier, T.; Racca, C.; Riccobene, G.; Roensch, K.; Saldaña, M.; Samtleben, D. F. E.; Sanguineti, M.; Sapienza, P.; Schnabel, J.; Schüssler, F.; Seitz, T.; Sieger, C.; Spurio, M.; Stolarczyk, Th.; Sánchez-Losa, A.; Taiuti, M.; Trovato, A.; Tselengidou, M.; Turpin, D.; Tönnis, C.; Vallage, B.; Vallée, C.; Van Elewyck, V.; Vivolo, D.; Wagner, S.; Wilms, J.; Zornoza, J. D.; Zuñiga, J.

    2017-01-01

    Despite dedicated research has been carried out to adequately map the distribution of the sperm whale in the Mediterranean Sea, unlike other regions of the world, the species population status is still presently uncertain. The analysis of two years of continuous acoustic data provided by the ANTARES neutrino telescope revealed the year-round presence of sperm whales in the Ligurian Sea, probably associated with the availability of cephalopods in the region. The presence of the Ligurian Sea sperm whales was demonstrated through the real-time analysis of audio data streamed from a cabled-to-shore deep-sea observatory that allowed the hourly tracking of their long-range echolocation behaviour on the Internet. Interestingly, the same acoustic analysis indicated that the occurrence of surface shipping noise would apparently not condition the foraging behaviour of the sperm whale in the area, since shipping noise was almost always present when sperm whales were acoustically detected. The continuous presence of the sperm whale in the region confirms the ecological value of the Ligurian sea and the importance of ANTARES to help monitoring its ecosystems. PMID:28401960

  3. Sperm whale long-range echolocation sounds revealed by ANTARES, a deep-sea neutrino telescope.

    PubMed

    André, M; Caballé, A; van der Schaar, M; Solsona, A; Houégnigan, L; Zaugg, S; Sánchez, A M; Castell, J V; Solé, M; Vila, F; Djokic, D; Adrián-Martínez, S; Albert, A; Anghinolfi, M; Anton, G; Ardid, M; Aubert, J-J; Avgitas, T; Baret, B; Barrios-Martí, J; Basa, S; Bertin, V; Biagi, S; Bormuth, R; Bouwhuis, M C; Bruijn, R; Brunner, J; Busto, J; Capone, A; Caramete, L; Carr, J; Celli, S; Chiarusi, T; Circella, M; Coleiro, A; Coniglione, R; Costantini, H; Coyle, P; Creusot, A; Deschamps, A; De Bonis, G; Distefano, C; Di Palma, I; Donzaud, C; Dornic, D; Drouhin, D; Eberl, T; El Bojaddaini, I; Elsässer, D; Enzenhöfer, A; Fehn, K; Felis, I; Fusco, L A; Galatà, S; Gay, P; Geißelsöder, S; Geyer, K; Giordano, V; Gleixner, A; Glotin, H; Gracia-Ruiz, R; Graf, K; Hallmann, S; van Haren, H; Heijboer, A J; Hello, Y; Hernandez-Rey, J J; Hößl, J; Hofestädt, J; Hugon, C; Illuminati, G; James, C W; de Jong, M; Jongen, M; Kadler, M; Kalekin, O; Katz, U; Kießling, D; Kouchner, A; Kreter, M; Kreykenbohm, I; Kulikovskiy, V; Lachaud, C; Lahmann, R; Lefèvre, D; Leonora, E; Loucatos, S; Marcelin, M; Margiotta, A; Marinelli, A; Martínez-Mora, J A; Mathieu, A; Melis, K; Michael, T; Migliozzi, P; Moussa, A; Mueller, C; Nezri, E; Păvălaş, G E; Pellegrino, C; Perrina, C; Piattelli, P; Popa, V; Pradier, T; Racca, C; Riccobene, G; Roensch, K; Saldaña, M; Samtleben, D F E; Sanguineti, M; Sapienza, P; Schnabel, J; Schüssler, F; Seitz, T; Sieger, C; Spurio, M; Stolarczyk, Th; Sánchez-Losa, A; Taiuti, M; Trovato, A; Tselengidou, M; Turpin, D; Tönnis, C; Vallage, B; Vallée, C; Van Elewyck, V; Vivolo, D; Wagner, S; Wilms, J; Zornoza, J D; Zuñiga, J

    2017-04-12

    Despite dedicated research has been carried out to adequately map the distribution of the sperm whale in the Mediterranean Sea, unlike other regions of the world, the species population status is still presently uncertain. The analysis of two years of continuous acoustic data provided by the ANTARES neutrino telescope revealed the year-round presence of sperm whales in the Ligurian Sea, probably associated with the availability of cephalopods in the region. The presence of the Ligurian Sea sperm whales was demonstrated through the real-time analysis of audio data streamed from a cabled-to-shore deep-sea observatory that allowed the hourly tracking of their long-range echolocation behaviour on the Internet. Interestingly, the same acoustic analysis indicated that the occurrence of surface shipping noise would apparently not condition the foraging behaviour of the sperm whale in the area, since shipping noise was almost always present when sperm whales were acoustically detected. The continuous presence of the sperm whale in the region confirms the ecological value of the Ligurian sea and the importance of ANTARES to help monitoring its ecosystems.

  4. Sperm whale long-range echolocation sounds revealed by ANTARES, a deep-sea neutrino telescope

    NASA Astrophysics Data System (ADS)

    André, M.; Caballé, A.; van der Schaar, M.; Solsona, A.; Houégnigan, L.; Zaugg, S.; Sánchez, A. M.; Castell, J. V.; Solé, M.; Vila, F.; Djokic, D.; Adrián-Martínez, S.; Albert, A.; Anghinolfi, M.; Anton, G.; Ardid, M.; Aubert, J.-J.; Avgitas, T.; Baret, B.; Barrios-Martí, J.; Basa, S.; Bertin, V.; Biagi, S.; Bormuth, R.; Bouwhuis, M. C.; Bruijn, R.; Brunner, J.; Busto, J.; Capone, A.; Caramete, L.; Carr, J.; Celli, S.; Chiarusi, T.; Circella, M.; Coleiro, A.; Coniglione, R.; Costantini, H.; Coyle, P.; Creusot, A.; Deschamps, A.; de Bonis, G.; Distefano, C.; di Palma, I.; Donzaud, C.; Dornic, D.; Drouhin, D.; Eberl, T.; El Bojaddaini, I.; Elsässer, D.; Enzenhöfer, A.; Fehn, K.; Felis, I.; Fusco, L. A.; Galatà, S.; Gay, P.; Geißelsöder, S.; Geyer, K.; Giordano, V.; Gleixner, A.; Glotin, H.; Gracia-Ruiz, R.; Graf, K.; Hallmann, S.; van Haren, H.; Heijboer, A. J.; Hello, Y.; Hernandez-Rey, J. J.; Hößl, J.; Hofestädt, J.; Hugon, C.; Illuminati, G.; James, C. W.; de Jong, M.; Jongen, M.; Kadler, M.; Kalekin, O.; Katz, U.; Kießling, D.; Kouchner, A.; Kreter, M.; Kreykenbohm, I.; Kulikovskiy, V.; Lachaud, C.; Lahmann, R.; Lefèvre, D.; Leonora, E.; Loucatos, S.; Marcelin, M.; Margiotta, A.; Marinelli, A.; Martínez-Mora, J. A.; Mathieu, A.; Melis, K.; Michael, T.; Migliozzi, P.; Moussa, A.; Mueller, C.; Nezri, E.; Păvălaş, G. E.; Pellegrino, C.; Perrina, C.; Piattelli, P.; Popa, V.; Pradier, T.; Racca, C.; Riccobene, G.; Roensch, K.; Saldaña, M.; Samtleben, D. F. E.; Sanguineti, M.; Sapienza, P.; Schnabel, J.; Schüssler, F.; Seitz, T.; Sieger, C.; Spurio, M.; Stolarczyk, Th.; Sánchez-Losa, A.; Taiuti, M.; Trovato, A.; Tselengidou, M.; Turpin, D.; Tönnis, C.; Vallage, B.; Vallée, C.; van Elewyck, V.; Vivolo, D.; Wagner, S.; Wilms, J.; Zornoza, J. D.; Zuñiga, J.

    2017-04-01

    Despite dedicated research has been carried out to adequately map the distribution of the sperm whale in the Mediterranean Sea, unlike other regions of the world, the species population status is still presently uncertain. The analysis of two years of continuous acoustic data provided by the ANTARES neutrino telescope revealed the year-round presence of sperm whales in the Ligurian Sea, probably associated with the availability of cephalopods in the region. The presence of the Ligurian Sea sperm whales was demonstrated through the real-time analysis of audio data streamed from a cabled-to-shore deep-sea observatory that allowed the hourly tracking of their long-range echolocation behaviour on the Internet. Interestingly, the same acoustic analysis indicated that the occurrence of surface shipping noise would apparently not condition the foraging behaviour of the sperm whale in the area, since shipping noise was almost always present when sperm whales were acoustically detected. The continuous presence of the sperm whale in the region confirms the ecological value of the Ligurian sea and the importance of ANTARES to help monitoring its ecosystems.

  5. Non-Markovianity, coherence, and system-environment correlations in a long-range collision model

    NASA Astrophysics Data System (ADS)

    Ćakmak, B.; Pezzutto, M.; Paternostro, M.; Müstecaplıoǧlu, Ö. E.

    2017-08-01

    We consider the dynamics of a collisional model in which both the system and environment are embodied by spin-1 /2 particles. In order to include non-Markovian features in our model, we introduce interactions among the environmental qubits and investigate the effect that different models of such interaction have on the degree of non-Markovianity of the system's dynamics. By extending that interaction beyond the nearest neighbor, we enhance the degree of non-Markovianity in the system's dynamics. A further significant increase can be observed if a collective interaction with the forthcoming environmental qubits is considered. However, the observed degree of non-Markovianity in this case is nonmonotonic with the increasing number of qubits included in the interaction. Moreover, one can establish a connection between the degree of non-Markovianity in the evolution of the system and the fading behavior of quantum coherence in its state as the number of collisions grows. We complement our study with an investigation of system-environment correlations and present an example of their importance on a physical upper bound on the trace distance derivative.

  6. Long-Range Coupling in an Allosteric Receptor Revealed by Mutant Cycle Analysis

    PubMed Central

    Gleitsman, Kristin R.; Shanata, Jai A.P.; Frazier, Shawnalea J.; Lester, Henry A.; Dougherty, Dennis A.

    2009-01-01

    Abstract The functional coupling of residues that are far apart in space is the quintessential property of allosteric proteins. For example, in Cys-loop receptors, the gating of an intrinsic ion channel is allosterically regulated by the binding of small molecule neurotransmitters 50–60 Å from the channel gate. Some residues near the binding site must have as their primary function the communication of the binding event to the gating region. These gating pathway residues are essential to function, but their identification and characterization can be challenging. This work introduces a simple strategy, derived from mutant cycle analysis, for identifying gating pathway residues using macroscopic measurements alone. In the exemplar Cys-loop receptor, the nicotinic acetylcholine receptor, a well-characterized reporter mutation (βL9′S) known to impact gating, was combined with mutations of target residues in the ligand-binding domain hypothesized or previously found to be functionally significant. A mutant cycle analysis of the macroscopic EC50 measurements can then provide insights into the role of the target residue. This new method, elucidating long-range functional coupling in allosteric receptors, can be applied to several reporter mutations in a wide variety of receptors to identify previously characterized and novel mutations that impact the gating pathway. We support our interpretation of macroscopic data with single-channel studies. Elucidating long-range functional coupling in allosteric receptors should be broadly applicable to determining functional roles of residues in allosteric receptors. PMID:19383461

  7. In vivo cross-sectional imaging of the phonating larynx using long-range Doppler optical coherence tomography

    PubMed Central

    Coughlan, Carolyn A.; Chou, Li-dek; Jing, Joseph C.; Chen, Jason J.; Rangarajan, Swathi; Chang, Theodore H.; Sharma, Giriraj K.; Cho, Kyoungrai; Lee, Donghoon; Goddard, Julie A.; Chen, Zhongping; Wong, Brian J. F.

    2016-01-01

    Diagnosis and treatment of vocal fold lesions has been a long-evolving science for the otolaryngologist. Contemporary practice requires biopsy of a glottal lesion in the operating room under general anesthesia for diagnosis. Current in-office technology is limited to visualizing the surface of the vocal folds with fiber-optic or rigid endoscopy and using stroboscopic or high-speed video to infer information about submucosal processes. Previous efforts using optical coherence tomography (OCT) have been limited by small working distances and imaging ranges. Here we report the first full field, high-speed, and long-range OCT images of awake patients’ vocal folds as well as cross-sectional video and Doppler analysis of their vocal fold motions during phonation. These vertical-cavity surface-emitting laser source (VCSEL) OCT images offer depth resolved, high-resolution, high-speed, and panoramic images of both the true and false vocal folds. This technology has the potential to revolutionize in-office imaging of the larynx. PMID:26960250

  8. In vivo cross-sectional imaging of the phonating larynx using long-range Doppler optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Coughlan, Carolyn A.; Chou, Li-Dek; Jing, Joseph C.; Chen, Jason J.; Rangarajan, Swathi; Chang, Theodore H.; Sharma, Giriraj K.; Cho, Kyoungrai; Lee, Donghoon; Goddard, Julie A.; Chen, Zhongping; Wong, Brian J. F.

    2016-03-01

    Diagnosis and treatment of vocal fold lesions has been a long-evolving science for the otolaryngologist. Contemporary practice requires biopsy of a glottal lesion in the operating room under general anesthesia for diagnosis. Current in-office technology is limited to visualizing the surface of the vocal folds with fiber-optic or rigid endoscopy and using stroboscopic or high-speed video to infer information about submucosal processes. Previous efforts using optical coherence tomography (OCT) have been limited by small working distances and imaging ranges. Here we report the first full field, high-speed, and long-range OCT images of awake patients’ vocal folds as well as cross-sectional video and Doppler analysis of their vocal fold motions during phonation. These vertical-cavity surface-emitting laser source (VCSEL) OCT images offer depth resolved, high-resolution, high-speed, and panoramic images of both the true and false vocal folds. This technology has the potential to revolutionize in-office imaging of the larynx.

  9. Revealing long-range multiparticle collectivity in small collision systems via subevent cumulants

    NASA Astrophysics Data System (ADS)

    Jia, Jiangyong; Zhou, Mingliang; Trzupek, Adam

    2017-09-01

    Multiparticle azimuthal cumulants, often used to study collective flow in high-energy heavy-ion collisions, have recently been applied in small collision systems such as p p and p +A to extract the second-order azimuthal harmonic flow v2. Recent observation of four-, six-, and eight-particle cumulants with "correct sign" c2{4 } <0 , c2{6 } >0 , c2{8 } <0 and approximate equality of the inferred single-particle harmonic flow, v2{4 } ≈v2{6 } ≈v2{8 } , have been used as strong evidence for a collective emission of all the soft particles produced in the collisions. We show that these relations in principle could be violated due to the non-Gaussianity in the event-by-event fluctuation of flow and/or nonflow. Furthermore, we show, using p p events generated with the pythia model, that c2{2 k } obtained with the standard cumulant method are dominated by nonflow from dijets. An alternative cumulant method based on two or more η -separated subevents is proposed to suppress the dijet contribution. The new method is shown to be able to recover a flow signal as low as 4% imposed on the pythia events, independently of how the event activity class is defined. Therefore the subevent cumulant method offers a more robust way of studying collectivity based on the existence of long-range azimuthal correlations between multiple distinct η ranges. The prospect of using the subevent cumulants to study collective flow in A +A collisions, in particular its longitudinal dynamics, is discussed.

  10. Morphology of central California continental margin, revealed by long-range side-scan sonar (GLORIA)

    SciTech Connect

    Gardner, J.V.; McCulloch, D.S.; Eittreim, S.L.; Masson, D.G.

    1985-02-01

    Leg 2 of the 4-leg USGS EEZ-SCAN 84 program used GLORIA long-range side-scan sonar to survey the region from Pt. Conception to just south of Pt. Arena, from the shelf break to the 200-nmi coverage. The overlapping digital sonographs were slant-range and anamorphically corrected, and a photomosaic of the sonographs was constructed at a scale of 1:375,000 (1 in. = 11.1 km). The underlying bed rock appears to be an important control in shaping the morphology of this margin. Several faults have sea-floor expression and lie subparallel to the margin. The density of canyons and gullies on the slope varies from south to north, probably because of variations in the characteristics of the bed rock. The slope west of San Francisco is the most dissected segment of the central California slope. Monterey Fan is covered by large-scale bed forms (5-15 m amplitude and 1.5-2.0 km wavelength) over much of its surface. Monterey channel crosses southwestward across the fan, but abruptly turns south along a 40-km long surface fault that coincides with a well-mapped meander loop. The channel loops to the north then turns southward crossing the entire Monterey Fan, at its distal reaches, changes to a broad, braided pattern. Major slumps on the margin have long (> 30 km) scarps, some have slump folds, and one has a debris-flow deposit that can be acoustically traced for more than 75 km. Seventeen new seamounts were mapped. Taney Seamounts are large, rimmed, calderas with diameters of about 15 km each; these appear to be very large explosive or summit-collapse features.

  11. Long-Range Optical Coherence Tomography of the Neonatal Upper Airway for Early Diagnosis of Intubation-related Subglottic Injury

    PubMed Central

    Sharma, Giriraj K.; Ahuja, Gurpreet S.; Wiedmann, Maximilian; Osann, Kathryn E.; Su, Erica; Heidari, Andrew E.; Jing, Joseph C.; Qu, Yueqiao; Lazarow, Frances; Wang, Alex; Chou, Lidek; Uy, Cherry C.; Dhar, Vijay; Cleary, John P.; Pham, Nguyen; Huoh, Kevin; Chen, Zhongping

    2015-01-01

    Rationale: Subglottic edema and acquired subglottic stenosis are potentially airway-compromising sequelae in neonates following endotracheal intubation. At present, no imaging modality is capable of in vivo diagnosis of subepithelial airway wall pathology as signs of intubation-related injury. Objectives: To use Fourier domain long-range optical coherence tomography (LR-OCT) to acquire micrometer-resolution images of the airway wall of intubated neonates in a neonatal intensive care unit setting and to analyze images for histopathology and airway wall thickness. Methods: LR-OCT of the neonatal laryngotracheal airway was performed a total of 94 times on 72 subjects (age, 1–175 d; total intubation, 1–104 d). LR-OCT images of the airway wall were analyzed in MATLAB. Medical records were reviewed retrospectively for extubation outcome. Measurements and Main Results: Backward stepwise regression analysis demonstrated a statistically significant association between log(duration of intubation) and both laryngeal (P < 0.001; multiple r2 = 0.44) and subglottic (P < 0.001; multiple r2 = 0.55) airway wall thickness. Subjects with positive histopathology on LR-OCT images had a higher likelihood of extubation failure (odds ratio, 5.9; P = 0.007). Longer intubation time was found to be significantly associated with extubation failure. Conclusions: LR-OCT allows for high-resolution evaluation and measurement of the airway wall in intubated neonates. Our data demonstrate a positive correlation between laryngeal and subglottic wall thickness and duration of intubation, suggestive of progressive soft tissue injury. LR-OCT may ultimately aid in the early diagnosis of postintubation subglottic injury and help reduce the incidences of failed extubation caused by subglottic edema or acquired subglottic stenosis in neonates. Clinical trial registered with www.clinicaltrials.gov (NCT 00544427). PMID:26214043

  12. Long-Range Phase Coherence in Double-Barrier Magnetic Tunnel Junctions with a Large Thick Metallic Quantum Well.

    PubMed

    Tao, B S; Yang, H X; Zuo, Y L; Devaux, X; Lengaigne, G; Hehn, M; Lacour, D; Andrieu, S; Chshiev, M; Hauet, T; Montaigne, F; Mangin, S; Han, X F; Lu, Y

    2015-10-09

    Double-barrier heterostructures are model systems for the study of electron tunneling and discrete energy levels in a quantum well (QW). Until now resonant tunneling phenomena in metallic QWs have been observed for limited thicknesses (1-2 nm) under which electron phase coherence is conserved. In the present study we show evidence of QW resonance states in Fe QWs up to 12 nm thick and at room temperature in fully epitaxial double MgAlO_{x} barrier magnetic tunnel junctions. The electron phase coherence displayed in this QW is of unprecedented quality because of a homogenous interface phase shift due to the small lattice mismatch at the Fe-MgAlO_{x} interface. The physical understanding of the critical role of interface strain on QW phase coherence will greatly promote the development of spin-dependent quantum resonant tunneling applications.

  13. Anatomically correct visualization of the human upper airway using a high-speed long range optical coherence tomography system with an integrated positioning sensor

    NASA Astrophysics Data System (ADS)

    Jing, Joseph C.; Chou, Lidek; Su, Erica; Wong, Brian J. F.; Chen, Zhongping

    2016-12-01

    The upper airway is a complex tissue structure that is prone to collapse. Current methods for studying airway obstruction are inadequate in safety, cost, or availability, such as CT or MRI, or only provide localized qualitative information such as flexible endoscopy. Long range optical coherence tomography (OCT) has been used to visualize the human airway in vivo, however the limited imaging range has prevented full delineation of the various shapes and sizes of the lumen. We present a new long range OCT system that integrates high speed imaging with a real-time position tracker to allow for the acquisition of an accurate 3D anatomical structure in vivo. The new system can achieve an imaging range of 30 mm at a frame rate of 200 Hz. The system is capable of generating a rapid and complete visualization and quantification of the airway, which can then be used in computational simulations to determine obstruction sites.

  14. Anatomically correct visualization of the human upper airway using a high-speed long range optical coherence tomography system with an integrated positioning sensor

    PubMed Central

    Jing, Joseph C.; Chou, Lidek; Su, Erica; Wong, Brian J. F.; Chen, Zhongping

    2016-01-01

    The upper airway is a complex tissue structure that is prone to collapse. Current methods for studying airway obstruction are inadequate in safety, cost, or availability, such as CT or MRI, or only provide localized qualitative information such as flexible endoscopy. Long range optical coherence tomography (OCT) has been used to visualize the human airway in vivo, however the limited imaging range has prevented full delineation of the various shapes and sizes of the lumen. We present a new long range OCT system that integrates high speed imaging with a real-time position tracker to allow for the acquisition of an accurate 3D anatomical structure in vivo. The new system can achieve an imaging range of 30 mm at a frame rate of 200 Hz. The system is capable of generating a rapid and complete visualization and quantification of the airway, which can then be used in computational simulations to determine obstruction sites. PMID:27991580

  15. Anatomically correct visualization of the human upper airway using a high-speed long range optical coherence tomography system with an integrated positioning sensor.

    PubMed

    Jing, Joseph C; Chou, Lidek; Su, Erica; Wong, Brian J F; Chen, Zhongping

    2016-12-19

    The upper airway is a complex tissue structure that is prone to collapse. Current methods for studying airway obstruction are inadequate in safety, cost, or availability, such as CT or MRI, or only provide localized qualitative information such as flexible endoscopy. Long range optical coherence tomography (OCT) has been used to visualize the human airway in vivo, however the limited imaging range has prevented full delineation of the various shapes and sizes of the lumen. We present a new long range OCT system that integrates high speed imaging with a real-time position tracker to allow for the acquisition of an accurate 3D anatomical structure in vivo. The new system can achieve an imaging range of 30 mm at a frame rate of 200 Hz. The system is capable of generating a rapid and complete visualization and quantification of the airway, which can then be used in computational simulations to determine obstruction sites.

  16. Fluctuation of long-range order in Co-Pt alloy nanoparticles revealed by time-resolved electron microscopy

    NASA Astrophysics Data System (ADS)

    Sato, Kazuhisa; Yasuda, Hidehiro

    2017-04-01

    The development of long-range order in disordered Co-Pt alloy nanoparticles has been atomically resolved in situ with an ultra-high voltage electron microscope equipped with a direct electron detection camera. Electron-irradiation-enhanced ordering occurred at 573 K with 1 MeV electrons at a dose rate of 8.9 × 1024 e/m2s. High-speed (400 frames/s) imaging revealed fluctuations of the c-axis orientation of the L10-type ordered structure. Specifically, the c-axis orientation changes occurred at 2.5-ms intervals. Thus, the atomic ordering rate at 573 K is deduced to be 3 × 10-17 m2/s, which is 1013 times higher than that estimated for interdiffusion in a bulk Co-Pt alloy. The observed kinetic ordering temperature of 573 K is significantly lower than that reported previously (>800 K). The low-temperature ordering may be the result of enhanced atom migration via excess vacancies, 106 times higher than that at thermal equilibrium, introduced by the high-energy electron irradiation.

  17. Long-range correlations in the mechanics of small DNA circles under topological stress revealed by multi-scale simulation

    PubMed Central

    Sutthibutpong, Thana; Matek, Christian; Benham, Craig; Slade, Gabriel G.; Noy, Agnes; Laughton, Charles; K. Doye, Jonathan P.; Louis, Ard A.

    2016-01-01

    Abstract It is well established that gene regulation can be achieved through activator and repressor proteins that bind to DNA and switch particular genes on or off, and that complex metabolic networks determine the levels of transcription of a given gene at a given time. Using three complementary computational techniques to study the sequence-dependence of DNA denaturation within DNA minicircles, we have observed that whenever the ends of the DNA are constrained, information can be transferred over long distances directly by the transmission of mechanical stress through the DNA itself, without any requirement for external signalling factors. Our models combine atomistic molecular dynamics (MD) with coarse-grained simulations and statistical mechanical calculations to span three distinct spatial resolutions and timescale regimes. While they give a consensus view of the non-locality of sequence-dependent denaturation in highly bent and supercoiled DNA loops, each also reveals a unique aspect of long-range informational transfer that occurs as a result of restraining the DNA within the closed loop of the minicircles. PMID:27664220

  18. Long-range correlations in the mechanics of small DNA circles under topological stress revealed by multi-scale simulation.

    PubMed

    Sutthibutpong, Thana; Matek, Christian; Benham, Craig; Slade, Gabriel G; Noy, Agnes; Laughton, Charles; K Doye, Jonathan P; Louis, Ard A; Harris, Sarah A

    2016-11-02

    It is well established that gene regulation can be achieved through activator and repressor proteins that bind to DNA and switch particular genes on or off, and that complex metabolic networks determine the levels of transcription of a given gene at a given time. Using three complementary computational techniques to study the sequence-dependence of DNA denaturation within DNA minicircles, we have observed that whenever the ends of the DNA are constrained, information can be transferred over long distances directly by the transmission of mechanical stress through the DNA itself, without any requirement for external signalling factors. Our models combine atomistic molecular dynamics (MD) with coarse-grained simulations and statistical mechanical calculations to span three distinct spatial resolutions and timescale regimes. While they give a consensus view of the non-locality of sequence-dependent denaturation in highly bent and supercoiled DNA loops, each also reveals a unique aspect of long-range informational transfer that occurs as a result of restraining the DNA within the closed loop of the minicircles. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

  19. Graph-theoretical model of global human interactome reveals enhanced long-range communicability in cancer networks

    PubMed Central

    Gladilin, Evgeny

    2017-01-01

    Malignant transformation is known to involve substantial rearrangement of the molecular genetic landscape of the cell. A common approach to analysis of these alterations is a reductionist one and consists of finding a compact set of differentially expressed genes or associated signaling pathways. However, due to intrinsic tumor heterogeneity and tissue specificity, biomarkers defined by a small number of genes/pathways exhibit substantial variability. As an alternative to compact differential signatures, global features of genetic cell machinery are conceivable. Global network descriptors suggested in previous works are, however, known to potentially be biased by overrepresentation of interactions between frequently studied genes-proteins. Here, we construct a cellular network of 74538 directional and differential gene expression weighted protein-protein and gene regulatory interactions, and perform graph-theoretical analysis of global human interactome using a novel, degree-independent feature—the normalized total communicability (NTC). We apply this framework to assess differences in total information flow between different cancer (BRCA/COAD/GBM) and non-cancer interactomes. Our experimental results reveal that different cancer interactomes are characterized by significant enhancement of long-range NTC, which arises from circulation of information flow within robustly organized gene subnetworks. Although enhancement of NTC emerges in different cancer types from different genomic profiles, we identified a subset of 90 common genes that are related to elevated NTC in all studied tumors. Our ontological analysis shows that these genes are associated with enhanced cell division, DNA replication, stress response, and other cellular functions and processes typically upregulated in cancer. We conclude that enhancement of long-range NTC manifested in the correlated activity of genes whose tight coordination is required for survival and proliferation of all tumor cells

  20. A first genetic map of date palm (Phoenix dactylifera) reveals long-range genome structure conservation in the palms.

    PubMed

    Mathew, Lisa S; Spannagl, Manuel; Al-Malki, Ameena; George, Binu; Torres, Maria F; Al-Dous, Eman K; Al-Azwani, Eman K; Hussein, Emad; Mathew, Sweety; Mayer, Klaus F X; Mohamoud, Yasmin Ali; Suhre, Karsten; Malek, Joel A

    2014-04-15

    The date palm is one of the oldest cultivated fruit trees. It is critical in many ways to cultures in arid lands by providing highly nutritious fruit while surviving extreme heat and environmental conditions. Despite its importance from antiquity, few genetic resources are available for improving the productivity and development of the dioecious date palm. To date there has been no genetic map and no sex chromosome has been identified. Here we present the first genetic map for date palm and identify the putative date palm sex chromosome. We placed ~4000 markers on the map using nearly 1200 framework markers spanning a total of 1293 cM. We have integrated the genetic map, derived from the Khalas cultivar, with the draft genome and placed up to 19% of the draft genome sequence scaffolds onto linkage groups for the first time. This analysis revealed approximately ~1.9 cM/Mb on the map. Comparison of the date palm linkage groups revealed significant long-range synteny to oil palm. Analysis of the date palm sex-determination region suggests it is telomeric on linkage group 12 and recombination is not suppressed in the full chromosome. Based on a modified genotyping-by-sequencing approach we have overcome challenges due to lack of genetic resources and provide the first genetic map for date palm. Combined with the recent draft genome sequence of the same cultivar, this resource offers a critical new tool for date palm biotechnology, palm comparative genomics and a better understanding of sex chromosome development in the palms.

  1. A first genetic map of date palm (Phoenix dactylifera) reveals long-range genome structure conservation in the palms

    PubMed Central

    2014-01-01

    Background The date palm is one of the oldest cultivated fruit trees. It is critical in many ways to cultures in arid lands by providing highly nutritious fruit while surviving extreme heat and environmental conditions. Despite its importance from antiquity, few genetic resources are available for improving the productivity and development of the dioecious date palm. To date there has been no genetic map and no sex chromosome has been identified. Results Here we present the first genetic map for date palm and identify the putative date palm sex chromosome. We placed ~4000 markers on the map using nearly 1200 framework markers spanning a total of 1293 cM. We have integrated the genetic map, derived from the Khalas cultivar, with the draft genome and placed up to 19% of the draft genome sequence scaffolds onto linkage groups for the first time. This analysis revealed approximately ~1.9 cM/Mb on the map. Comparison of the date palm linkage groups revealed significant long-range synteny to oil palm. Analysis of the date palm sex-determination region suggests it is telomeric on linkage group 12 and recombination is not suppressed in the full chromosome. Conclusions Based on a modified gentoyping-by-sequencing approach we have overcome challenges due to lack of genetic resources and provide the first genetic map for date palm. Combined with the recent draft genome sequence of the same cultivar, this resource offers a critical new tool for date palm biotechnology, palm comparative genomics and a better understanding of sex chromosome development in the palms. PMID:24735434

  2. Revealing Hidden Coherence in Partially Coherent Light.

    PubMed

    Svozilík, Jiří; Vallés, Adam; Peřina, Jan; Torres, Juan P

    2015-11-27

    Coherence and correlations represent two related properties of a compound system. The system can be, for instance, the polarization of a photon, which forms part of a polarization-entangled two-photon state, or the spatial shape of a coherent beam, where each spatial mode bears different polarizations. Whereas a local unitary transformation of the system does not affect its coherence, global unitary transformations modifying both the system and its surroundings can enhance its coherence, transforming mutual correlations into coherence. The question naturally arises of what is the best measure that quantifies the correlations that can be turned into coherence, and how much coherence can be extracted. We answer both questions, and illustrate its application for some typical simple systems, with the aim at illuminating the general concept of enhancing coherence by modifying correlations.

  3. Revealing Hidden Coherence in Partially Coherent Light

    NASA Astrophysics Data System (ADS)

    Svozilík, Jiří; Vallés, Adam; Peřina, Jan; Torres, Juan P.

    2015-11-01

    Coherence and correlations represent two related properties of a compound system. The system can be, for instance, the polarization of a photon, which forms part of a polarization-entangled two-photon state, or the spatial shape of a coherent beam, where each spatial mode bears different polarizations. Whereas a local unitary transformation of the system does not affect its coherence, global unitary transformations modifying both the system and its surroundings can enhance its coherence, transforming mutual correlations into coherence. The question naturally arises of what is the best measure that quantifies the correlations that can be turned into coherence, and how much coherence can be extracted. We answer both questions, and illustrate its application for some typical simple systems, with the aim at illuminating the general concept of enhancing coherence by modifying correlations.

  4. Long-range chemical orders in Au-Pd nanoparticles revealed by aberration-corrected electron microscopy

    NASA Astrophysics Data System (ADS)

    Nelayah, Jaysen; Nguyen, Nhat Tai; Alloyeau, Damien; Wang, Guillaume Yangshu; Ricolleau, Christian

    2014-08-01

    Despite the importance of gold-palladium nanoalloys in heterogeneous catalysis, the phase stability of Au-Pd alloys still remains unclear. We report here on the alloying and chemical ordering in epitaxially-grown and post-annealed gold-palladium nanoparticles (NPs) using aberration-corrected transmission electron microscopy. Au-Pd NPs with a controlled size, composition and structure were grown by pulsed laser deposition on freshly-cleaved NaCl(001) single crystals heated at 300 °C. After transfer to an amorphous carbon support, the NPs were annealed in vacuum at elevated temperatures above 400 °C for a few hours (6-10 hours) to promote chemical ordering. The as-grown NPs were mostly monocrystalline with a chemically-disordered face-centered cubic structure. Upon high-temperature annealing, a high degree of chemical ordering was observed in nanometer-sized NPs. Electron microscopy measurements showed that both L10 and L12 orders are stabilized in the Au-rich region of the Au-Pd phase diagram. These ordered phases exist at temperatures as high as 600 °C. Moreover, compositional analysis of single annealed particles revealed that the observed chemical ordering occurs in parallel to a two-tiered Ostwald ripening process. Due to this ripening process, a clear dependence between chemical composition and particle size is established during annealing with an enrichment in Pd as the NPs grow in size. Our results, besides clarifying some controversial aspects about long-range order in Au-Pd alloys, shed light on the structural stability of Au-Pd nanoalloys at elevated temperatures.Despite the importance of gold-palladium nanoalloys in heterogeneous catalysis, the phase stability of Au-Pd alloys still remains unclear. We report here on the alloying and chemical ordering in epitaxially-grown and post-annealed gold-palladium nanoparticles (NPs) using aberration-corrected transmission electron microscopy. Au-Pd NPs with a controlled size, composition and structure were grown

  5. Long-range chemical orders in Au-Pd nanoparticles revealed by aberration-corrected electron microscopy.

    PubMed

    Nelayah, Jaysen; Nguyen, Nhat Tai; Alloyeau, Damien; Wang, Guillaume Yangshu; Ricolleau, Christian

    2014-09-07

    Despite the importance of gold-palladium nanoalloys in heterogeneous catalysis, the phase stability of Au-Pd alloys still remains unclear. We report here on the alloying and chemical ordering in epitaxially-grown and post-annealed gold-palladium nanoparticles (NPs) using aberration-corrected transmission electron microscopy. Au-Pd NPs with a controlled size, composition and structure were grown by pulsed laser deposition on freshly-cleaved NaCl(001) single crystals heated at 300 °C. After transfer to an amorphous carbon support, the NPs were annealed in vacuum at elevated temperatures above 400 °C for a few hours (6-10 hours) to promote chemical ordering. The as-grown NPs were mostly monocrystalline with a chemically-disordered face-centered cubic structure. Upon high-temperature annealing, a high degree of chemical ordering was observed in nanometer-sized NPs. Electron microscopy measurements showed that both L10 and L12 orders are stabilized in the Au-rich region of the Au-Pd phase diagram. These ordered phases exist at temperatures as high as 600 °C. Moreover, compositional analysis of single annealed particles revealed that the observed chemical ordering occurs in parallel to a two-tiered Ostwald ripening process. Due to this ripening process, a clear dependence between chemical composition and particle size is established during annealing with an enrichment in Pd as the NPs grow in size. Our results, besides clarifying some controversial aspects about long-range order in Au-Pd alloys, shed light on the structural stability of Au-Pd nanoalloys at elevated temperatures.

  6. Dynamics of functional connectivity at high spatial resolution reveal long-range interactions and fine-scale organization.

    PubMed

    Preti, Maria Giulia; Van De Ville, Dimitri

    2017-10-06

    Dynamic functional connectivity (dFC) derived from resting-state functional magnetic resonance imaging sheds light onto moment-to-moment reconfigurations of large-scale functional brain networks. Due to computational limits, connectivity is typically computed using pre-defined atlases, a non-trivial choice that might influence results. Here, we leverage new computational methods to retrieve dFC at the voxel level in terms of dominant patterns of fluctuations, and demonstrate that this new representation is informative to derive meaningful brain parcellations, capturing both long-range interactions and fine-scale local organization. Specifically, voxelwise dFC dominant patterns were captured through eigenvector centrality followed by clustering across time/subjects to yield most representative dominant patterns (RDPs). Voxel-wise labeling according to positive/negative contributions to RDPs, led to 37 unique labels identifying strikingly symmetric dFC long-range patterns. These included 449 contiguous regions, defining a fine-scale parcellation consistent with known cortical/subcortical subdivisions. Our contribution provides an alternative to obtain a whole-brain parcellation that is for the first time driven by voxel-level dFC and bridges the gap between voxel-based approaches and graph theoretical analysis.

  7. Phase-amplitude coupling and long-range phase synchronization reveal frontotemporal interactions during visual working memory.

    PubMed

    Daume, Jonathan; Gruber, Thomas; Engel, Andreas K; Friese, Uwe

    2016-11-30

    It has been suggested that cross-frequency phase-amplitude coupling (PAC) particularly in temporal brain structures serves as a neural mechanism for coordinated working memory storage. In this magnetoencephalography study, we show that during visual working memory maintenance, temporal cortex regions, which exhibit enhanced PAC, interact with prefrontal cortex via enhanced low-frequency phase synchronization. Healthy human participants were engaged in a visual delayed-matching-to-sample task with pictures of natural objects. During the delay period, we observed increased spectral power of beta (20-28 Hz) and gamma band (40-94 Hz) as well as decreased power of theta/alpha band (7-9 Hz) oscillations in visual sensory areas. Enhanced PAC between the phases of theta/alpha and the amplitudes of beta oscillations was found in the left inferior temporal cortex (IT) - an area known to be involved in visual object memory. Furthermore, the IT was functionally connected to the prefrontal cortex by increased low-frequency phase synchronization within the theta/alpha band. Taken together, these results point to a mechanism, in which the combination of PAC and long-range phase synchronization subserves enhanced large-scale brain communication. They suggest that distant brain regions might coordinate their activity in the low-frequency range to engage local stimulus-related processing in higher frequencies via the combination of long-range within-frequency phase synchronization and local cross-frequency PAC. Working memory maintenance, like other cognitive functions, requires the coordinated engagement of brain areas in local and large-scale networks. However, the mechanisms by which spatially distributed brain regions share and combine information remain largely unknown. We show that the combination of long-range low-frequency phase synchronization and local cross-frequency phase-amplitude coupling might serve as a mechanism to coordinate memory processes across distant brain

  8. Phase-Amplitude Coupling and Long-Range Phase Synchronization Reveal Frontotemporal Interactions during Visual Working Memory.

    PubMed

    Daume, Jonathan; Gruber, Thomas; Engel, Andreas K; Friese, Uwe

    2017-01-11

    It has been suggested that cross-frequency phase-amplitude coupling (PAC), particularly in temporal brain structures, serves as a neural mechanism for coordinated working memory storage. In this magnetoencephalography study, we show that during visual working memory maintenance, temporal cortex regions, which exhibit enhanced PAC, interact with prefrontal cortex via enhanced low-frequency phase synchronization. Healthy human participants were engaged in a visual delayed match-to-sample task with pictures of natural objects. During the delay period, we observed increased spectral power of beta (20-28 Hz) and gamma (40-94 Hz) bands as well as decreased power of theta/alpha band (7-9 Hz) oscillations in visual sensory areas. Enhanced PAC between the phases of theta/alpha and the amplitudes of beta oscillations was found in the left inferior temporal cortex (IT), an area known to be involved in visual object memory. Furthermore, the IT was functionally connected to the prefrontal cortex by increased low-frequency phase synchronization within the theta/alpha band. Together, these results point to a mechanism in which the combination of PAC and long-range phase synchronization subserves enhanced large-scale brain communication. They suggest that distant brain regions might coordinate their activity in the low-frequency range to engage local stimulus-related processing in higher frequencies via the combination of long-range, within-frequency phase synchronization and local cross-frequency PAC. Working memory maintenance, like other cognitive functions, requires the coordinated engagement of brain areas in local and large-scale networks. However, the mechanisms by which spatially distributed brain regions share and combine information remain primarily unknown. We show that the combination of long-range, low-frequency phase synchronization and local cross-frequency phase-amplitude coupling might serve as a mechanism to coordinate memory processes across distant brain areas

  9. Fast, long-range, reversible conformational fluctuations in nucleosomes revealed by single-pair fluorescence resonance energy transfer

    NASA Astrophysics Data System (ADS)

    Tomschik, Miroslav; Zheng, Haocheng; van Holde, Ken; Zlatanova, Jordanka; Leuba, Sanford H.

    2005-03-01

    The nucleosome core particle, the basic repeated structure in chromatin fibers, consists of an octamer of eight core histone molecules, organized as dimers (H2A/H2B) and tetramers [(H3/H4)2] around which DNA wraps tightly in almost two left-handed turns. The nucleosome has to undergo certain conformational changes to allow processes that need access to the DNA template to occur. By single-pair fluorescence resonance energy transfer, we demonstrate fast, long-range, reversible conformational fluctuations in nucleosomes between two states: fully folded (closed), with the DNA wrapped around the histone core, or open, with the DNA significantly unraveled from the histone octamer. The brief excursions into an extended open state may create windows of opportunity for protein factors involved in DNA transactions to bind to or translocate along the DNA. conformational transitions | evanescent field fluorescence microscope | nucleosome dynamics | nucleosome opening

  10. Tryptophan fluorescence reveals the presence of long-range interactions in the denatured state of ribonuclease Sa.

    PubMed

    Alston, Roy W; Lasagna, Mauricio; Grimsley, Gerald R; Scholtz, J Martin; Reinhart, Gregory D; Pace, C Nick

    2008-03-15

    Characterizing the denatured state ensemble is crucial to understanding protein stability and the mechanism of protein folding. The aim of this research was to see if fluorescence could be used to gain new information on the denatured state ensemble. Ribonuclease Sa (RNase Sa) contains no Trp residues. We made five variants of RNase Sa by adding Trp residues at locations where they are found in other members of the microbial ribonuclease family. To better understand the protein denatured state, we also studied the fluorescence properties of the following peptides: N-acetyl-Trp-amide (NATA), N-acetyl-Ala-Trp-Ala-amide (AWA), N-acetyl-Ala-Ala-Trp-Ala-Ala-amide (AAWAA), and the five pentapeptides with the same sequence as the Trp substitution sites in RNase Sa. The major conclusions are: 1), the wavelength of maximum fluorescence intensity, lambda(max), does not differ significantly for the peptides and the denatured proteins; 2), the fluorescence intensity at lambda(max), I(F), differs significantly for the five Trp containing variants of RNase Sa; 3), the I(F) differences for the denatured proteins are mirrored in the peptides, showing that the short-range effects giving rise to the I(F) differences in the peptides are also present in the proteins; 4) the I(F) values for the denatured proteins are more than 30% greater than for the peptides, showing the presence of long-range effects in the proteins; 5), fluorescence quenching of Trp by acrylamide and iodide is more than 50% greater in the peptides than in the denatured proteins, showing that long-range effects limit the accessibility of the quenchers to the Trp side chains in the proteins; and 6), these results show that nonlocal effects in the denatured states of proteins influence Trp fluorescence and accessibility significantly.

  11. Long Range Technology Planning.

    ERIC Educational Resources Information Center

    Ambron, Sueann, Ed.

    1986-01-01

    This summary of a meeting of the Apple Education Advisory Council, on long range technology plans at the state, county, district, and school levels, includes highlights from group discussions on future planning, staff development, and curriculum. Three long range technology plans at the state level are provided: Long Range Educational Technology…

  12. Long Range Technology Planning.

    ERIC Educational Resources Information Center

    Ambron, Sueann, Ed.

    1986-01-01

    This summary of a meeting of the Apple Education Advisory Council, on long range technology plans at the state, county, district, and school levels, includes highlights from group discussions on future planning, staff development, and curriculum. Three long range technology plans at the state level are provided: Long Range Educational Technology…

  13. Long-range and depth-selective imaging of macroscopic targets using low-coherence and wide-field interferometry (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Woo, Sungsoo; Kang, Sungsam; Yoon, Changhyeong; Choi, Wonshik

    2016-03-01

    With the advancement of 3D display technology, 3D imaging of macroscopic objects has drawn much attention as they provide the contents to display. The most widely used imaging methods include a depth camera, which measures time of flight for the depth discrimination, and various structured illumination techniques. However, these existing methods have poor depth resolution, which makes imaging complicated structures a difficult task. In order to resolve this issue, we propose an imaging system based upon low-coherence interferometry and off-axis digital holographic imaging. By using light source with coherence length of 200 micro, we achieved the depth resolution of 100 micro. In order to map the macroscopic objects with this high axial resolution, we installed a pair of prisms in the reference beam path for the long-range scanning of the optical path length. Specifically, one prism was fixed in position, and the other prism was mounted on a translation stage and translated in parallel to the first prism. Due to the multiple internal reflections between the two prisms, the overall path length was elongated by a factor of 50. In this way, we could cover a depth range more than 1 meter. In addition, we employed multiple speckle illuminations and incoherent averaging of the acquired holographic images for reducing the specular reflections from the target surface. Using this newly developed system, we performed imaging targets with multiple different layers and demonstrated imaging targets hidden behind the scattering layers. The method was also applied to imaging targets located around the corner.

  14. Long-range and wide field of view optical coherence tomography for in vivo 3D imaging of large volume object based on akinetic programmable swept source.

    PubMed

    Song, Shaozhen; Xu, Jingjiang; Wang, Ruikang K

    2016-11-01

    Current optical coherence tomography (OCT) imaging suffers from short ranging distance and narrow imaging field of view (FOV). There is growing interest in searching for solutions to these limitations in order to expand further in vivo OCT applications. This paper describes a solution where we utilize an akinetic swept source for OCT implementation to enable ~10 cm ranging distance, associated with the use of a wide-angle camera lens in the sample arm to provide a FOV of ~20 x 20 cm(2). The akinetic swept source operates at 1300 nm central wavelength with a bandwidth of 100 nm. We propose an adaptive calibration procedure to the programmable akinetic light source so that the sensitivity of the OCT system over ~10 cm ranging distance is substantially improved for imaging of large volume samples. We demonstrate the proposed swept source OCT system for in vivo imaging of entire human hands and faces with an unprecedented FOV (up to 400 cm(2)). The capability of large-volume OCT imaging with ultra-long ranging and ultra-wide FOV is expected to bring new opportunities for in vivo biomedical applications.

  15. Long-range and wide field of view optical coherence tomography for in vivo 3D imaging of large volume object based on akinetic programmable swept source

    PubMed Central

    Song, Shaozhen; Xu, Jingjiang; Wang, Ruikang K.

    2016-01-01

    Current optical coherence tomography (OCT) imaging suffers from short ranging distance and narrow imaging field of view (FOV). There is growing interest in searching for solutions to these limitations in order to expand further in vivo OCT applications. This paper describes a solution where we utilize an akinetic swept source for OCT implementation to enable ~10 cm ranging distance, associated with the use of a wide-angle camera lens in the sample arm to provide a FOV of ~20 x 20 cm2. The akinetic swept source operates at 1300 nm central wavelength with a bandwidth of 100 nm. We propose an adaptive calibration procedure to the programmable akinetic light source so that the sensitivity of the OCT system over ~10 cm ranging distance is substantially improved for imaging of large volume samples. We demonstrate the proposed swept source OCT system for in vivo imaging of entire human hands and faces with an unprecedented FOV (up to 400 cm2). The capability of large-volume OCT imaging with ultra-long ranging and ultra-wide FOV is expected to bring new opportunities for in vivo biomedical applications. PMID:27896012

  16. Semi-Discrete Wavelet Transforms of Remote Sensing Data Reveal Long-Range Multifractal Correlations in Cloud Structure

    NASA Astrophysics Data System (ADS)

    Petrov, N. P.; Davis, A. B.

    2001-12-01

    -scaling) fractal signals. In particular, this implies the presence of long-range correlations in cloud structure coming from the important nonstationary regime. Finally, ramifications of this finding for cloud-radiation interaction are discussed in the context of climate modeling.

  17. Spherical Harmonics Reveal Standing EEG Waves and Long-Range Neural Synchronization during Non-REM Sleep

    PubMed Central

    Sivakumar, Siddharth S.; Namath, Amalia G.; Galán, Roberto F.

    2016-01-01

    Previous work from our lab has demonstrated how the connectivity of brain circuits constrains the repertoire of activity patterns that those circuits can display. Specifically, we have shown that the principal components of spontaneous neural activity are uniquely determined by the underlying circuit connections, and that although the principal components do not uniquely resolve the circuit structure, they do reveal important features about it. Expanding upon this framework on a larger scale of neural dynamics, we have analyzed EEG data recorded with the standard 10–20 electrode system from 41 neurologically normal children and adolescents during stage 2, non-REM sleep. We show that the principal components of EEG spindles, or sigma waves (10–16 Hz), reveal non-propagating, standing waves in the form of spherical harmonics. We mathematically demonstrate that standing EEG waves exist when the spatial covariance and the Laplacian operator on the head's surface commute. This in turn implies that the covariance between two EEG channels decreases as the inverse of their relative distance; a relationship that we corroborate with empirical data. Using volume conduction theory, we then demonstrate that superficial current sources are more synchronized at larger distances, and determine the characteristic length of large-scale neural synchronization as 1.31 times the head radius, on average. Moreover, consistent with the hypothesis that EEG spindles are driven by thalamo-cortical rather than cortico-cortical loops, we also show that 8 additional patients with hypoplasia or complete agenesis of the corpus callosum, i.e., with deficient or no connectivity between cortical hemispheres, similarly exhibit standing EEG waves in the form of spherical harmonics. We conclude that spherical harmonics are a hallmark of spontaneous, large-scale synchronization of neural activity in the brain, which are associated with unconscious, light sleep. The analogy with spherical harmonics

  18. Spherical Harmonics Reveal Standing EEG Waves and Long-Range Neural Synchronization during Non-REM Sleep.

    PubMed

    Sivakumar, Siddharth S; Namath, Amalia G; Galán, Roberto F

    2016-01-01

    Previous work from our lab has demonstrated how the connectivity of brain circuits constrains the repertoire of activity patterns that those circuits can display. Specifically, we have shown that the principal components of spontaneous neural activity are uniquely determined by the underlying circuit connections, and that although the principal components do not uniquely resolve the circuit structure, they do reveal important features about it. Expanding upon this framework on a larger scale of neural dynamics, we have analyzed EEG data recorded with the standard 10-20 electrode system from 41 neurologically normal children and adolescents during stage 2, non-REM sleep. We show that the principal components of EEG spindles, or sigma waves (10-16 Hz), reveal non-propagating, standing waves in the form of spherical harmonics. We mathematically demonstrate that standing EEG waves exist when the spatial covariance and the Laplacian operator on the head's surface commute. This in turn implies that the covariance between two EEG channels decreases as the inverse of their relative distance; a relationship that we corroborate with empirical data. Using volume conduction theory, we then demonstrate that superficial current sources are more synchronized at larger distances, and determine the characteristic length of large-scale neural synchronization as 1.31 times the head radius, on average. Moreover, consistent with the hypothesis that EEG spindles are driven by thalamo-cortical rather than cortico-cortical loops, we also show that 8 additional patients with hypoplasia or complete agenesis of the corpus callosum, i.e., with deficient or no connectivity between cortical hemispheres, similarly exhibit standing EEG waves in the form of spherical harmonics. We conclude that spherical harmonics are a hallmark of spontaneous, large-scale synchronization of neural activity in the brain, which are associated with unconscious, light sleep. The analogy with spherical harmonics in

  19. Mapping of long-range INS promoter interactions reveals a role for calcium-activated chloride channel ANO1 in insulin secretion.

    PubMed

    Xu, Zhixiong; Lefevre, Gaelle M; Gavrilova, Oksana; Foster St Claire, Mark B; Riddick, Gregory; Felsenfeld, Gary

    2014-11-25

    We used circular chromatin conformation capture (4C) to identify a physical contact in human pancreatic islets between the region near the insulin (INS) promoter and the ANO1 gene, lying 68 Mb away on human chromosome 11, which encodes a Ca(2+)-dependent chloride ion channel. In response to glucose, this contact was strengthened and ANO1 expression increased, whereas inhibition of INS gene transcription by INS promoter targeting siRNA decreased ANO1 expression, revealing a regulatory effect of INS promoter on ANO1 expression. Knockdown of ANO1 expression caused decreased insulin secretion in human islets, establishing a physical proximity-dependent feedback loop involving INS transcription, ANO1 expression, and insulin secretion. To explore a possible role of ANO1 in insulin metabolism, we carried out experiments in Ano1(+/-) mice. We observed reduced serum insulin levels and insulin-to-glucose ratios in high-fat diet-fed Ano1(+/-) mice relative to Ano1(+/+) mice fed the same diet. Our results show that determination of long-range contacts within the nucleus can be used to detect novel and physiologically relevant mechanisms. They also show that networks of long-range physical contacts are important to the regulation of insulin metabolism.

  20. Mapping of long-range INS promoter interactions reveals a role for calcium-activated chloride channel ANO1 in insulin secretion

    PubMed Central

    Xu, Zhixiong; Lefevre, Gaelle M.; Gavrilova, Oksana; Foster St. Claire, Mark B.; Riddick, Gregory; Felsenfeld, Gary

    2014-01-01

    We used circular chromatin conformation capture (4C) to identify a physical contact in human pancreatic islets between the region near the insulin (INS) promoter and the ANO1 gene, lying 68 Mb away on human chromosome 11, which encodes a Ca2+-dependent chloride ion channel. In response to glucose, this contact was strengthened and ANO1 expression increased, whereas inhibition of INS gene transcription by INS promoter targeting siRNA decreased ANO1 expression, revealing a regulatory effect of INS promoter on ANO1 expression. Knockdown of ANO1 expression caused decreased insulin secretion in human islets, establishing a physical proximity-dependent feedback loop involving INS transcription, ANO1 expression, and insulin secretion. To explore a possible role of ANO1 in insulin metabolism, we carried out experiments in Ano1+/− mice. We observed reduced serum insulin levels and insulin-to-glucose ratios in high-fat diet–fed Ano1+/− mice relative to Ano1+/+ mice fed the same diet. Our results show that determination of long-range contacts within the nucleus can be used to detect novel and physiologically relevant mechanisms. They also show that networks of long-range physical contacts are important to the regulation of insulin metabolism. PMID:25385647

  1. Institutional Long Range Planning.

    ERIC Educational Resources Information Center

    Caldwell Community Coll. and Technical Inst., Lenoir, NC.

    Long-range institutional planning has been in effect at Caldwell Community College and Technical Institute since 1973. The first step in the process was the identification of planning areas: administration, organization, educational programs, learning resources, student services, faculty, facilities, maintenance/operation, and finances. The major…

  2. Long Range Plan.

    ERIC Educational Resources Information Center

    Jefferson Coll., Hillsboro, MO.

    This document presents Jefferson College's "Long Range Plan," which is intended to provide the College's governing board, administration, and faculty and staff with a task-oriented blueprint for maximizing the delivery of higher education services to students and the community in a predictable, programmatic, and fiscally sound manner.…

  3. Long Range Facilities Planning

    DTIC Science & Technology

    1982-04-01

    Richard Muther range facilities Many alterna- analysis indi- cated that if NASSCO ever expected to surpass its output of the last several years, current...Marine Engineers (SNAME) SP-1 Panel Meeting. The Maritime Administration had Richard Muther (an authority on long range facility planning) address a

  4. Long range chromatin organization

    PubMed Central

    Acuña, Luciana I Gómez; Kornblihtt, Alberto R

    2014-01-01

    Splicing is a predominantly co-transcriptional process that has been shown to be tightly coupled to transcription. Chromatin structure is a key factor that mediates this functional coupling. In light of recent evidence that shows the importance of higher order chromatin organization in the coordination and regulation of gene expression, we discuss here the possible roles of long-range chromatin organization in splicing and alternative splicing regulation. PMID:25764333

  5. Application of a long-range swept source optical coherence tomography-based scheme for dimensional characterization of multilayer transparent objects

    NASA Astrophysics Data System (ADS)

    Morel, Eneas N.; Russo, Nélida A.; Torga, Jorge R.; Duchowicz, Ricardo

    2017-08-01

    This work presents the use of a recently developed interferometric system based on the swept source optical coherence tomography (SS-OCT) technique, which allows the characterization of transparent and semitransparent multilayer systems employing a tunable fiber-optic laser with a coherence length suitable for achieving long-deep range imaging (>10 cm). The inclusion of fiber Bragg gratings in the system allows it to perform a self-calibration in each sweep of the light source. Measurements carried out on cuvettes, ampoules, small bottles, and glass containers used in the pharmaceutical industry are presented. The thicknesses of the walls and the distance between them were determined. Transparent and semitransparent objects of a multilayer type of different thicknesses were also measured. The configuration presented allows extension of the measurement range obtainable with the usual OCT systems, demonstrating the potentiality of the proposed scheme to carry out quality control in industrial applications.

  6. Anatomy and growth pattern of Amazon deep-sea fan as revealed by long-range side-scan sonar (GLORIA) and high-resolution seismic studies

    SciTech Connect

    Damuth, J.E.; Flood, R.D.; Kowsmann, R.O.; Belderson, R.H.; Gorini, M.A.

    1988-08-01

    Imaging of the Amazon deep-sea fan with long-range side-scan sonar (GLORIA) has, for the first time, revealed the anatomy, trends, and growth pattern of distributary channels on this fan. Only one channel-levee system was active at any given time and extended from the Amazon Submarine Canyon downslope onto the lower fan (> 4,200 m). Formation of new channel-levee systems occurred when a currently active channel-levee system was cut off and abandoned through avulsion, and a new channel-levee system was established nearby. Through time, successive channel-levee formation and abandonment built two broad levee complexes consisting of groups of overlapping, coalescing segments of channel-levee systems across the present fan surface. These, plus older, now buried levee complexes, indicate that fan growth is radially outward and downslope through development of successive levee complexes. The most striking characteristic of the distributary channels is their intricate, often recurving, meanders with sinuosities of up to 2.5. Cutoffs and abandoned meander loops indicate that the channels migrate laterally through time. Channel bifurcation results predominantly from avulsion when flows breach a channel levee, thereby abandoning the present channel and establishing a new channel-levee segment nearby. No clear evidence of channel branching (i.e., division of a single channel into two active segments) or braiding was observed. 22 figs.

  7. Long-range chromatin interactions at the mouse Igf2/H19 locus reveal a novel paternally expressed long non-coding RNA

    PubMed Central

    Court, Franck; Baniol, Marion; Hagege, Hélène; Petit, Julie Sandrine; Lelay-Taha, Marie-Noëlle; Carbonell, Françoise; Weber, Michael; Cathala, Guy; Forne, Thierry

    2011-01-01

    Parental genomic imprinting at the Igf2/H19 locus is controlled by a methylation-sensitive CTCF insulator that prevents the access of downstream enhancers to the Igf2 gene on the maternal chromosome. However, on the paternal chromosome, it remains unclear whether long-range interactions with the enhancers are restricted to the Igf2 promoters or whether they encompass the entire gene body. Here, using the quantitative chromosome conformation capture assay, we show that, in the mouse liver, the endodermal enhancers have low contact frequencies with the Igf2 promoters but display, on the paternal chromosome, strong interactions with the intragenic differentially methylated regions 1 and 2. Interestingly, we found that enhancers also interact with a so-far poorly characterized intergenic region of the locus that produces a novel imprinted long non-coding transcript that we named the paternally expressed Igf2/H19 intergenic transcript (PIHit) RNA. PIHit is expressed exclusively from the paternal chromosome, contains a novel discrete differentially methylated region in a highly conserved sequence and, surprisingly, does not require an intact ICR/H19 gene region for its imprinting. Altogether, our data reveal a novel imprinted domain in the Igf2/H19 locus and lead us to propose a model for chromatin folding of this locus on the paternal chromosome. PMID:21478171

  8. Long-range interaction between the Mn4CaO5 cluster and the non-heme iron center in photosystem II as revealed by FTIR spectroelectrochemistry.

    PubMed

    Kato, Yuki; Noguchi, Takumi

    2014-08-05

    It is known that inactivation of the Mn4CaO5 cluster, the catalytic center of water oxidation in photosystem II (PSII), induces a positive shift of the redox potential (Em) of the primary quinone electron acceptor QA by ∼+150 mV, resulting in suppression of the electron transfer from QA to the secondary quinone acceptor QB. Although the relevance of this Em(QA(-)/QA) shift to the photoprotection of PSII has been debated, its molecular mechanism is still enigmatic from a structural viewpoint because QA is ∼40 Å from the Mn4CaO5 cluster. In this work, we have investigated the influence of Mn depletion on the Em of the non-heme iron, which is located between QA and QB, and its surrounding structure. Electrochemical measurements in combination with Fourier transform infrared (FTIR) spectroscopy revealed that Mn depletion shifts Em(Fe(2+)/Fe(3+)) by +18 mV, which is ∼8 times smaller than the shift of Em(QA(-)/QA). Comparison of the Fe(2+)/Fe(3+) FTIR difference spectra between intact and Mn-depleted PSII samples showed that Mn depletion altered the pKa's of a His ligand to the non-heme iron, most probably the D1-His215 interacting QB, and a carboxylate group, possibly D1-Glu244, coupled with the non-heme iron. It was further shown that Mn depletion influences the C≡N vibration of bromoxynil bound to the QB site, indicative of the modification of the QB binding site. On the basis of these results, we discuss the mechanism of a long-range interaction between the donor and acceptor sides of PSII.

  9. Cryo-EM of the pathogenic VCP variant R155P reveals long-range conformational changes in the D2 ATPase ring

    SciTech Connect

    Mountassif, Driss; Fabre, Lucien; Zaid, Younes; Halawani, Dalia; Rouiller, Isabelle

    2015-12-25

    Single amino acid mutations in valosin containing protein (VCP/p97), a highly conserved member of the ATPases associated with diverse cellular activities (AAA) family of ATPases has been linked to a severe degenerative disease affecting brain, muscle and bone tissue. Previous studies have demonstrated the role of VCP mutations in altering the ATPase activity of the D2 ring; however the structural consequences of these mutations remain unclear. In this study, we report the three-dimensional (3D) map of the pathogenic VCP variant, R155P, as revealed by single-particle Cryo-Electron Microscopy (EM) analysis at 14 Å resolution. We show that the N-terminal R155P mutation induces a large structural reorganisation of the D2 ATPase ring. Results from docking studies using crystal structure data of available wild-type VCP in the EM density maps indicate that the major difference is localized at the interface between two protomers within the D2 ring. Consistent with a conformational change, the VCP R155P variant shifted the isoelectric point of the protein and reduced its interaction with its well-characterized cofactor, nuclear protein localization-4 (Npl4). Together, our results demonstrate that a single amino acid substitution in the N-terminal domain can relay long-range conformational changes to the distal D2 ATPase ring. Our results provide the first structural clues of how VCP mutations may influence the activity and function of the D2 ATPase ring. - Highlights: • p97{sub R155P} and p97{sub A232E} decrease the ability of p97 to bind to its co-factor Npl4. • p97{sub R155P} has a different isoelectric point than that of p97{sub R95G}, p97{sub A232E} and p97{sub WT}. • Mutation R155P changes principally the conformation of the D2 ring. • Mutation R155P modifies the interface between two protomers within the D2 ring.

  10. Long Range, Coherent Synthetic Aperture Communications

    DTIC Science & Technology

    2009-09-30

    coupling of time and space in the presence of source motion. PUBLICATIONS 1. G.E. Edelmann , T. Akal, W.S. Hodgkiss, S. Kim, W.A. Kuperman, and H.C...communications in shallow water: Experimental demonstration at sea,” J. Acoust. Soc. Am. 118(4), 2365-2372, 2005 [published, refereed]. 3. G.F. Edelmann , H.C

  11. Movement-related changes in local and long-range synchronization in Parkinson’s disease revealed by simultaneous magnetoencephalography and intracranial recordings

    PubMed Central

    Litvak, Vladimir; Eusebio, Alexandre; Jha, Ashwani; Oostenveld, Robert; Barnes, Gareth; Foltynie, Tom; Limousin, Patricia; Zrinzo, Ludvic; Hariz, Marwan I.; Friston, Karl; Brown, Peter

    2012-01-01

    Functional neurosurgery has afforded the opportunity to assess interactions between populations of neurons in the human cerebral cortex and basal ganglia in patients with Parkinson’s disease (PD). Interactions occur over a wide range of frequencies, and the functional significance of those above 30 Hz is particularly unclear. Do they improve movement and, if so, in what way? We acquired simultaneously magnetoencephalography (MEG) and direct recordings from the subthalamic nucleus (STN) in 17 PD patients. We examined the effect of synchronous and sequential finger movements and of the dopamine prodrug levodopa on induced power in the contralateral primary motor cortex (M1) and STN and on the coherence between the two structures. We observed discrete peaks in M1 and STN power over 60-90 Hz and 300-400 Hz. All these power peaks increased with movement and levodopa treatment. Only STN activity over 60-90 Hz was coherent with activity in M1. Directionality analysis showed that STN gamma activity at 60-90 Hz tended to drive gamma activity in M1. The effects of levodopa on both local and distant synchronisation over 60-90 Hz correlated with the degree of improvement in bradykinesia-rigidity, as did local STN activity at 300-400 Hz. Despite this, there were no effects of movement type, nor interactions between movement type and levodopa in the STN, nor in the coherence between STN and M1. We conclude that synchronisation over 60-90 Hz in the basal ganglia cortical network is prokinetic, but likely through a modulatory effect rather than any involvement in explicit motor processing. PMID:22855804

  12. Intraaxonal injection of neurobiotin reveals the long-ranging projections of A beta-hair follicle afferent fibers to the cat dorsal horn.

    PubMed

    Wilson, P; Kitchener, P D; Snow, P J

    1996-07-01

    1. The morphology and somatotopic organization of the spinal arborizations of identified A beta-hair follicle afferent fibers (HFAs) with receptive fields (RFs) on the digits have been investigated in the cat by the use of intraaxonal injection of the tracer n-(2 aminoethyl) biotinamide. 2. In three cats, the long-ranging projections of six HFAs were examined by selectively injecting afferents with RFs on digit 2, 4, or 5, directly over the digit 3 representation, and examining their collateral morphology in transverse sections of the spinal cord. The rostral and caudal boundaries of the digit 3 representation were determined by mapping the RFs of identified spinocervical tract (SCT) neurons. 3. In two more cats, three HFAs were injected at random rostrocaudal positions and their morphology was examined in parasagittal sections. In one animal (2 HFAs), the somatotopy of the digit representation was again determined by mapping the RFs of SCT neurons. In the remaining cat (1 HFA), the somatotopy of the dorsal horn was mapped from the RFs of unidentified dorsal horn neurons. 4. Hair follicle afferents emitted many more collaterals, over much greater rostrocaudal distances, than indicated by previous horseradish peroxidase studies, and all collaterals gave rise to synaptic boutons. 5. HFAs that have RFs confined to a small part of a digit give rise to bouton-bearing axonal branches throughout the entire rostrocaudal extent of the hindpaw representation.

  13. Genome Analysis of Clostridium difficile PCR Ribotype 014 Lineage in Australian Pigs and Humans Reveals a Diverse Genetic Repertoire and Signatures of Long-Range Interspecies Transmission.

    PubMed

    Knight, Daniel R; Squire, Michele M; Collins, Deirdre A; Riley, Thomas V

    2016-01-01

    Clostridium difficile PCR ribotype (RT) 014 is well-established in both human and porcine populations in Australia, raising the possibility that C. difficile infection (CDI) may have a zoonotic or foodborne etiology. Here, whole genome sequencing and high-resolution core genome phylogenetics were performed on a contemporaneous collection of 40 Australian RT014 isolates of human and porcine origin. Phylogenies based on MLST (7 loci, STs 2, 13, and 49) and core orthologous genes (1260 loci) showed clustering of human and porcine strains indicative of very recent shared ancestry. Core genome single nucleotide variant (SNV) analysis found 42% of human strains showed a clonal relationship (separated by ≤2 SNVs in their core genome) with one or more porcine strains, consistent with recent inter-host transmission. Clones were spread over a vast geographic area with 50% of the human cases occurring without recent healthcare exposure. These findings suggest a persistent community reservoir with long-range dissemination, potentially due to agricultural recycling of piggery effluent. We also provide the first pan-genome analysis for this lineage, characterizing its resistome, prophage content, and in silico virulence potential. The RT014 is defined by a large "open" pan-genome (7587 genes) comprising a core genome of 2296 genes (30.3% of the total gene repertoire) and an accessory genome of 5291 genes. Antimicrobial resistance genotypes and phenotypes varied across host populations and ST lineages and were characterized by resistance to tetracycline [tetM, tetA(P), tetB(P) and tetW], clindamycin/erythromycin (ermB), and aminoglycosides (aph3-III-Sat4A-ant6-Ia). Resistance was mediated by clinically important mobile genetic elements, most notably Tn6194 (harboring ermB) and a novel variant of Tn5397 (harboring tetM). Numerous clinically important prophages (Siphoviridae and Myoviridae) were identified as well as an uncommon accessory gene regulator locus (agr3). Conservation

  14. Life-Sized Lahar Measurements Reveal the Entrainment and Stream-Flow Interaction Dynamics that Control the Long-Range Destructiveness of Water-Particle Mass Flows

    NASA Astrophysics Data System (ADS)

    Lube, G.; Cronin, S. J.; Manville, V.; Procter, J.; Cole, S. E.; Freundt, A.

    2011-12-01

    Lahars, debris flows and sediment-rich floods are frequent and deadly hazards at all mountain-forming volcanoes. Most current numerical models (including frequently- and worldwide-applied hazard assessment tools) are centered on the assumption that the main flow behavior is well captured by a closed system scheme. The closed system approach, which describes an energy cascade of the potential energy of an initially released mass to higher states of entropy through energy conversions, allows concepts borrowed from classical continuum fluid mechanics to be applied to complex geophysical mass flows. It also implies the development of peak flow energy and hence maximum flow destruction potential on the steepest volcano flanks. However, this belies observations of extremely high energy and deadly catastrophes caused by such flows at large distances from volcanoes. On 18 March 2007 the largest lahar in recent history in New Zealand occurred at Mount Ruapehu after sudden breaching of the rim of its Crater Lake. The event was anticipated providing a rare opportunity to plan for directly measuring its time- and space-variant structure, hydraulic, kinematic, chemical and sedimentary characteristics over the entire >200 km long runout path. Here we use this first-ever, high-resolution record of a moving lahar to develop a new model of the temporally and spatially variable mass-flow structure. We show that bulk flow energy can grow dramatically in such systems over 10's to 100's of km via momentum transfers from the lahar into water and particles along its path. This quantifies the prevalence of long-range destruction potential far beyond previously suggested "proximal hazard zones". Further, we explain that the lahar wave form can be subdivided into three main (and traceable) parts: a frontal bow wave of pure stream water, the head of the lahar proper representing the mixing zone between lahar bow wave and lahar proper, and the trailing lahar tail. We also demonstrate that

  15. Genome Analysis of Clostridium difficile PCR Ribotype 014 Lineage in Australian Pigs and Humans Reveals a Diverse Genetic Repertoire and Signatures of Long-Range Interspecies Transmission

    PubMed Central

    Knight, Daniel R.; Squire, Michele M.; Collins, Deirdre A.; Riley, Thomas V.

    2017-01-01

    Clostridium difficile PCR ribotype (RT) 014 is well-established in both human and porcine populations in Australia, raising the possibility that C. difficile infection (CDI) may have a zoonotic or foodborne etiology. Here, whole genome sequencing and high-resolution core genome phylogenetics were performed on a contemporaneous collection of 40 Australian RT014 isolates of human and porcine origin. Phylogenies based on MLST (7 loci, STs 2, 13, and 49) and core orthologous genes (1260 loci) showed clustering of human and porcine strains indicative of very recent shared ancestry. Core genome single nucleotide variant (SNV) analysis found 42% of human strains showed a clonal relationship (separated by ≤2 SNVs in their core genome) with one or more porcine strains, consistent with recent inter-host transmission. Clones were spread over a vast geographic area with 50% of the human cases occurring without recent healthcare exposure. These findings suggest a persistent community reservoir with long-range dissemination, potentially due to agricultural recycling of piggery effluent. We also provide the first pan-genome analysis for this lineage, characterizing its resistome, prophage content, and in silico virulence potential. The RT014 is defined by a large “open” pan-genome (7587 genes) comprising a core genome of 2296 genes (30.3% of the total gene repertoire) and an accessory genome of 5291 genes. Antimicrobial resistance genotypes and phenotypes varied across host populations and ST lineages and were characterized by resistance to tetracycline [tetM, tetA(P), tetB(P) and tetW], clindamycin/erythromycin (ermB), and aminoglycosides (aph3-III-Sat4A-ant6-Ia). Resistance was mediated by clinically important mobile genetic elements, most notably Tn6194 (harboring ermB) and a novel variant of Tn5397 (harboring tetM). Numerous clinically important prophages (Siphoviridae and Myoviridae) were identified as well as an uncommon accessory gene regulator locus (agr3

  16. Long range electrostatic forces in ionic liquids.

    PubMed

    Gebbie, Matthew A; Smith, Alexander M; Dobbs, Howard A; Lee, Alpha A; Warr, Gregory G; Banquy, Xavier; Valtiner, Markus; Rutland, Mark W; Israelachvili, Jacob N; Perkin, Susan; Atkin, Rob

    2017-01-19

    Ionic liquids are pure salts that are liquid under ambient conditions. As liquids composed solely of ions, the scientific consensus has been that ionic liquids have exceedingly high ionic strengths and thus very short Debye screening lengths. However, several recent experiments from laboratories around the world have reported data for the approach of two surfaces separated by ionic liquids which revealed remarkable long range forces that appear to be electrostatic in origin. Evidence has accumulated demonstrating long range surface forces for several different combinations of ionic liquids and electrically charged surfaces, as well as for concentrated mixtures of inorganic salts in solvent. The original interpretation of these forces, that ionic liquids could be envisioned as "dilute electrolytes," was controversial, and the origin of long range forces in ionic liquids remains the subject of discussion. Here we seek to collate and examine the evidence for long range surface forces in ionic liquids, identify key outstanding questions, and explore possible mechanisms underlying the origin of these long range forces. Long range surface forces in ionic liquids and other highly concentrated electrolytes hold diverse implications from designing ionic liquids for energy storage applications to rationalizing electrostatic correlations in biological self-assembly.

  17. Long-range laser-illuminated imaging

    NASA Astrophysics Data System (ADS)

    Dayton, David C.; Browne, Stephen L.; Sandven, Steven C.; Gonglewski, John D.; Gallegos, Joe; Shilko, Michael L., Sr.

    2000-11-01

    We demonstrate the utility of laser illuminated imaging for clandestine night time surveillance from a simulated airborne platform at standoff ranges in excess 20 km. In order to reduce the necessary laser per pulse energy required for illumination at such long ranges, and to mitigate atmospheric turbulence effects on image resolution, we have investigated a unique multi-frame post-processing technique. It is shown that in the presence of atmospheric turbulence and coherent speckle effects, this approach can produce superior results to conventional scene flood illumination.

  18. Molecular dynamics investigations of membrane-bound CYP2C19 polymorphisms reveal distinct mechanisms for peripheral variants by long-range effects on the enzymatic activity.

    PubMed

    Cui, Ying-Lu; Wu, Rong-Ling

    2017-06-01

    Increasing sophistication in methods used to account for human polymorphisms in susceptibility to drug metabolism has been one of the success stories in the prevention of adverse drug reactions. Genetic polymorphisms in drug-metabolizing enzymes can affect enzyme activity and cause differences in treatment response or drug toxicity. CYP2C19 is one of the most highly polymorphic CYP enzymes and acts on 10-15% of drugs in current clinical use. Despite the number of experimental analyses carried out for this system, the detailed structural basis for altered catalytic properties of polymorphic CYP2C19 variants remains unexplained at the atomic level. To this end, we have investigated the mutation effects on structural characteristics and tunnel geometry upon single point mutations to elucidate the underlying molecular mechanism for the enzymatic activity deficiencies by using the fully atomistic molecular dynamics (MD) simulations in their native, membrane-bound cellular environment. The obtained results demonstrate how significant sequence divergence causes heterogeneous variations, and further affects the shape and chemical properties of the substrate binding site. Principal component analysis (PCA) results combined with free energy calculations have revealed distinct mechanisms for different peripheral variants, implying a more complicated process for the decrease/loss of enzymatic activity upon the introduction of point mutations in CYP2C19 rather than simply structural changes of the region where the mutation is located. Overall, our present study provides important insights into the current pharmacogenetic knowledge of human drug-metabolizing CYP2C19 to understand the large inter-individual variability in drug clearance. The knowledge of heterogeneous variations in structural features could guide future experimental and computational work on efficient and safe drug treatment with better pharmacokinetic properties based on the common variant alleles of CYP genes

  19. USAKA Long Range Planning Study

    DTIC Science & Technology

    1990-03-01

    ORGANIZATION ERIM (if applicable ) United States Army I Strategic Defense Command 6c ADDRESS ICty. State. and ZIP Code) 7b ADDRESS (City, State. and ZIP...IDENTIFICATION NUMBER ORGANIZATION (if applicable ) US Army Strategic Def.Com. CSSD-H-KT DASG60-89-C-0013 8c ADDRESS (City, State. and ZIP Code) 10...activities. These are natural applications for the high power long range, well situated radars located at Kwajalein. The objective of the study described

  20. Long-range electron transfer

    PubMed Central

    Gray, Harry B.; Winkler, Jay R.

    2005-01-01

    Recent investigations have shed much light on the nuclear and electronic factors that control the rates of long-range electron tunneling through molecules in aqueous and organic glasses as well as through bonds in donor–bridge–acceptor complexes. Couplings through covalent and hydrogen bonds are much stronger than those across van der Waals gaps, and these differences in coupling between bonded and nonbonded atoms account for the dependence of tunneling rates on the structure of the media between redox sites in Ru-modified proteins and protein–protein complexes. PMID:15738403

  1. Long Range Fast Tool Servo

    DTIC Science & Technology

    1993-05-31

    AD-A271 614 r, FINAL REPORT w to I OFFICE OF NAVAL RESEARCH [I on * LONG RANGE FAST TOOL SERVO I ONR CONTRACT NO. N00014-92-J-4082-PII Covering the...n I I 1 INTRODUCTION The PEC’s MAC 100 Fast Tool Servo (FTS) System has demonstrated the efficacy of fabricating off-axis parabolic segments on axis...by utilizing a fast tool motion to machine non-rotationally symmetric surfaces [1]. The key to this technique was a servo for the tool motion that had

  2. Long range planning at NASA

    NASA Technical Reports Server (NTRS)

    Bekey, Ivan

    1987-01-01

    NASA's current plans for the U.S. space program are described. Consideration is given to the debate between manned or unmanned exploration of space, missions to the moon versus missions to Mars, and the exploration of space applications or science. NASA has created the Office of Policy and Planning and the Office of Exploration in order to improve the planning of future space activities. Long-range trends such as second-generation Shuttles, cargo launch vehicles with large capacity systems, an advanced Space Station, the use of robotics, closed cycle life support, health maintenance techniques, and the processing of extraterrestrial materials are considered.

  3. Long range handheld thermal imager

    NASA Astrophysics Data System (ADS)

    Seibel, Edward; Struckhoff, Andrew; McDaniel, Robert; Shamai, Shlomo

    2006-05-01

    Today's warfighter requires a lightweight, high performance thermal imager for use in night and reduced visibility conditions. To fill this need, the United States Marine Corps issued requirements for a Thermal Binocular System (TBS) Long Range Thermal Imager (LRTI). The requirements dictated that the system be lightweight, but still have significant range capabilities and extended operating time on a single battery load. Kollsman, Inc. with our partner Electro-Optics Industries, Ltd. (ElOp) responded to this need with the CORAL - a third-generation, Military Off-the-Shelf (MOTS) product that required very little modification to fully meet the LRTI specification. This paper will discuss the LRTI, a successful result of size, weight and power (SWaP) tradeoffs made to ensure a lightweight, but high performance thermal imager.

  4. Long-Range Neutron Detection

    SciTech Connect

    AJ Peurrung; DC Stromswold; RR Hansen; PL Reeder; DS Barnett

    1999-11-24

    A neutron detector designed for detecting neutron sources at distances of 50 to 100 m has been constructed and tested. This detector has a large surface area (1 m{sup 2}) to enhance detection efficiency, and it contains a collimator and shielding to achieve direction sensitivity and reduce background. An unusual feature of the detector is that it contains no added moderator, such as polyethylene, to moderate fast neutrons before they reach the {sup 3}He detector. As a result, the detector is sensitive mainly to thermal neutrons. The moderator-free design reduces the weight of the detector, making it more portable, and it also aids in achieving directional sensitivity and background reduction. Test results show that moderated fission-neutron sources of strength about 3 x 10{sup 5} n/s can be detected at a distance out to 70 m in a counting time of 1000 s. The best angular resolution of the detector is obtained at distances of 30 m or less. As the separation .distance between the source and detector increases, the contribution of scattered neutrons to the measured signal increases with a resultant decrease in the ability to detect the direction to a distant source. Applications for which the long-range detector appears to be suitable include detecting remote neutron sources (including sources in moving vehicles) and monitoring neutron storage vaults for the intrusion of humans and the effects they make on the detected neutron signal. Also, the detector can be used to measure waste for the presence of transuranic material in the presence of high gamma-ray background. A test with a neutron source (3 x 10{sup 5} n/s) in a vehicle showed that the detector could readily measure an increase in count rate at a distance of 10 m for vehicle speeds up to 35 mph (the highest speed tested). These results. indicate that the source should be detectable at this distance at speeds up to 55 mph.

  5. Long Range Interactions in Nanoscale Science

    SciTech Connect

    French, Roger H; Parsegian, V Adrian; Podgonik, Rudolph; Rajter, Rick; Jagota, Anand; Luo, Jian; Asthagiri, Dilip; Chaudhury, Manoj; Chiang, Yet-Ming; Granick, Steve; Kalinin, Sergei V; Kardar, Mehran; Kjellander, Roland; Langreth, David C.; Lewis, Jennifer; Lustig, Steve; Wesolowski, David J; Wettlaufer, John; Ching, Wai-Yim; Finnis, Mike; Houlihan, Frank; Von Lilienfeld, O. Anatole; Van Oss, Carel; Zemb, Thomas

    2010-01-01

    Our understanding of the long range electrodynamic, electrostatic, and polar interactions that dominate the organization of small objects at separations beyond an interatomic bond length is reviewed. From this basic-forces perspective, a large number of systems are described from which one can learn about these organizing forces and how to modulate them. The many practical systems that harness these nanoscale forces are then surveyed. The survey reveals not only the promise of new devices and materials, but also the possibility of designing them more effectively.

  6. Advanced Climate Analysis and Long Range Forecasting

    DTIC Science & Technology

    2014-09-30

    1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Advanced Climate Analysis and Long Range Forecasting...project is to improve the long range and climate support provided by the U.S. Naval Oceanography Enterprise (NOe) for planning, conducting, and...months, several seasons, several years). The primary transition focus is on improving the long range and climate support capabilities of the Fleet

  7. Long-range, wide-field swept-source optical coherence tomography with GPU accelerated digital lock-in Doppler vibrography for real-time, in vivo middle ear diagnostics

    PubMed Central

    MacDougall, Dan; Farrell, Joshua; Brown, Jeremy; Bance, Manohar; Adamson, Robert

    2016-01-01

    We present the design, implementation and validation of a swept-source optical coherence tomography (OCT) system for real-time imaging of the human middle ear in live patients. Our system consists of a highly phase-stable Vernier-tuned distributed Bragg-reflector laser along with a real-time processing engine implemented on a graphics processing unit. We use the system to demonstrate, for the first time in live subjects, real-time Doppler measurements of middle ear vibration in response to sound, video rate 2D B-mode imaging of the middle ear and 3D volumetric B-mode imaging. All measurements were performed non-invasively through the intact tympanic membrane demonstrating that the technology is readily translatable to the clinic. PMID:27896001

  8. The Long-Range Impact of Television.

    ERIC Educational Resources Information Center

    Comstock, George

    Long range effects may be of three varieties: those which are observable in the immediate period subsequent to exposure but are long range because of their continuing repetitive accumulation with each exposure; those which represent the cumulative or delayed impact on individuals of exposure to television; or those which represent the immediate…

  9. Long Range Plan, 1997-2000.

    ERIC Educational Resources Information Center

    Pennsylvania Coll. of Technology, Williamsport. Office of Strategic Planning and Research.

    At Pennsylvania College of Technology (PCT), long range planning is used to define institutional philosophy and mission and determine strategies to make the best use of available resources and implement actions to fulfill institutional mission. This document presents PCT's long-range plan for 1997-2000 in three parts. The first part describes long…

  10. Long-Range Tunneling Processes across Ferritin-Based Junctions.

    PubMed

    Kumar, Karuppannan Senthil; Pasula, Rupali Reddy; Lim, Sierin; Nijhuis, Christian A

    2016-03-02

    The mechanism of long-range charge transport across tunneling junctions with monolayers of ferritin is investigated. It is shown that the mechanism can be switched between coherent tunneling, sequential tunneling, and hopping by changing the iron content inside the ferritin. This study shows that ferritins are an interesting class of biomolecules to control charge transport. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Long-range correlations in computer diskettes

    NASA Astrophysics Data System (ADS)

    Zebende, G. F.; de Oliveira, P. M. C.; Penna, T. J. P.

    1998-03-01

    We find that successive versions of the files stored on a personal computer diskette mimic the evolution mechanism claimed to be responsible for the long-range correlations observed in DNA sequences. Starting from uncorrelated random files, long-range correlations are gradually introduced by successive editing, corresponding to point mutations, insertions, and deletions. This system has the advantage (over DNA sequences) of allowing experiments.

  12. Long range correlation in earthquake precursory signals

    NASA Astrophysics Data System (ADS)

    Chaudhuri, H.; Barman, C.; Iyengar, A. N. S.; Ghose, D.; Sen, P.; Sinha, B.

    2013-07-01

    Research on earthquake prediction has drawn serious attention of the geophysicist, geologist and investigators in different fields of science across the globe for many decades. Researchers around the world are actively working on recording pre-earthquake changes in non-seismic parameters through a variety of methods that include anomalous changes in geochemical parameters of the Earth's crust, geophysical properties of the lithosphere as well as ionosphere etc. Several works also have been done in India to detect earthquake precursor signals using geochemical and geophysical methods. However, very few works have been done so far in India in this field through the application of nonlinear techniques to the recorded geophysical and geochemical precursory signals for earthquakes. The present paper deals with a short review of the early works on geochemical precursors that have been carried out in India as yet. With a view to detect earthquake precursory signals by means of gas-geochemical method we developed a network of seismo-geochemical monitoring observatories in India in hot springs and mud volcano crater. In the last few years we detected several geochemical anomalies and those were observed prior to some major earthquakes that occurred within a radius of 1500 km from the test sites. In the present paper we have applied nonlinear techniques to the long term, real-time and natural data sets of radon-222 and associated gamma originated out of the terrestrial degassing process of the earth. The results reveal a clear signature of the long range correlation present in the geochemical time series. This approach appears to be a potential tool to explore intrinsic information hidden within the earthquake precursory signals.

  13. Photon assisted long-range tunneling

    SciTech Connect

    Gallego-Marcos, Fernando; Sánchez, Rafael; Platero, Gloria

    2015-03-21

    We analyze long-range transport through an ac driven triple quantum dot with a single electron. Resonant transitions between separated and detuned dots are mediated by the exchange of n photons with the time-dependent field. An effective model is proposed in terms of second order (cotunneling) processes which dominate the long-range transport between the edge quantum dots. The ac field renormalizes the inter dot hopping, modifying the level hybridization. It results in a non-trivial behavior of the current with the frequency and amplitude of the external ac field.

  14. Passive long range acousto-optic sensor

    NASA Astrophysics Data System (ADS)

    Slater, Dan

    2006-08-01

    Alexander Graham Bell's photophone of 1880 was a simple free space optical communication device that used the sun to illuminate a reflective acoustic diaphragm. A selenium photocell located 213 m (700 ft) away converted the acoustically modulated light beam back into sound. A variation of the photophone is presented here that uses naturally formed free space acousto-optic communications links to provide passive multichannel long range acoustic sensing. This system, called RAS (remote acoustic sensor), functions as a long range microphone with a demonstrated range in excess of 40 km (25 miles).

  15. Muskegon Community College Long-Range Plan.

    ERIC Educational Resources Information Center

    Turner, Peter M.; And Others

    Long-range planning assumptions and goals are presented for Muskegon Community College (MCC) as they were submitted by a committee of area citizens. After introductory material summarizing the committee's mandate and activities, the report discusses the fiscal, demographic, curricular, and administrative changes likely to affect MCC during the…

  16. Long Range Program for Georgia Public Libraries.

    ERIC Educational Resources Information Center

    Georgia State Dept of Education, Atlanta. Div. of Public Library Services.

    The development of each area of Georgia's long range plan required the identification of present and projected needs, the definition of objectives and action plans to meet those needs, establishment of periodic evaluation procedures, dissemination of information, coordination with all types of libraries and their programs, allocations of funds for…

  17. Long Range Planning and Organizational Performance

    ERIC Educational Resources Information Center

    Karger, Delmar W.; Malik, Zafar A.

    1975-01-01

    The cited research very clearly indicates that the top management of any profit-seeking organization is delinquent or grossly negligent if it does not engage in fully integrated long-range planning--at least this would seem to be true in the ordinary case. (Author)

  18. Resources and Long-Range Forecasts

    ERIC Educational Resources Information Center

    Smith, Waldo E.

    1973-01-01

    The author argues that forecasts of quick depletion of resources in the environment as a result of overpopulation and increased usage may not be free from error. Ignorance still exists in understanding the recovery mechanisms of nature. Long-range forecasts are likely to be wrong in such situations. (PS)

  19. Look Ahead: Long-Range Learning Plans

    ERIC Educational Resources Information Center

    Weinstein, Margery

    2010-01-01

    Faced with an unsteady economy and fluctuating learning needs, planning a learning strategy designed to last longer than the next six months can be a tall order. But a long-range learning plan can provide a road map for success. In this article, four companies (KPMG LLP, CarMax, DPR Construction, and EMC Corp.) describe their learning plans, and…

  20. Resources and Long-Range Forecasts

    ERIC Educational Resources Information Center

    Smith, Waldo E.

    1973-01-01

    The author argues that forecasts of quick depletion of resources in the environment as a result of overpopulation and increased usage may not be free from error. Ignorance still exists in understanding the recovery mechanisms of nature. Long-range forecasts are likely to be wrong in such situations. (PS)

  1. Lattice gas models with long range interactions

    NASA Astrophysics Data System (ADS)

    Aristoff, David; Zhu, Lingjiong

    2017-02-01

    We study microcanonical lattice gas models with long range interactions, including power law interactions. We rigorously obtain a variational principle for the entropy. In a one dimensional example, we find a first order phase transition by proving the entropy is non-differentiable along a certain curve.

  2. Look Ahead: Long-Range Learning Plans

    ERIC Educational Resources Information Center

    Weinstein, Margery

    2010-01-01

    Faced with an unsteady economy and fluctuating learning needs, planning a learning strategy designed to last longer than the next six months can be a tall order. But a long-range learning plan can provide a road map for success. In this article, four companies (KPMG LLP, CarMax, DPR Construction, and EMC Corp.) describe their learning plans, and…

  3. Discussion of long-range weather prediction

    SciTech Connect

    Canavan, G.H.

    1998-09-10

    A group of scientists at Los Alamos have held a series of discussions of the issues in and prospects for improvements in Long-range Weather Predictions Enabled by Proving of the Atmosphere at High Space-Time Resolution. The group contained the requisite skills for a full evaluation, although this report presents only an informal discussion of the main technical issues. The group discussed all aspects of the proposal, which are grouped below into the headings: (1) predictability; (2) sensors and satellites, (3) DIAL and atmospheric sensing; (4) localized transponders; and (5) summary and integration. Briefly, the group agreed that the relative paucity of observations of the state of the atmosphere severely inhibits the accuracy of weather forecasts, and any program that leads to a more dense and uniform observational network is welcome. As shown in Long-range Weather more dense and uniform observational network is welcome. As shown in Long-range Weather Predictions, the pay-back of accurate long-range forecasts should more than justify the expenditure associated with improved observations and forecast models required. The essential step is to show that the needed technologies are available for field test and space qualification.

  4. Long-Range Interactions Restrict Water Transport in Pyrophyllite Interlayers

    SciTech Connect

    Zarzycki, Piotr; Gilbert, Benjamin

    2016-04-27

    Water diffusion within smectite clay interlayers is reduced by confinement and hence is highly determined by the interlayer spacings that are adopted during swelling. However, a molecular understanding of the short-and long-range forces governing interlayer water structure and dynamics is lacking. Using molecular dynamics simulations of water intercalated between pyrophyllite (smectite prototype) layers we provide a detailed picture of the variation of interlayered water mobility accompanying smectite expansion. Subtle changes in hydrogen bond network structure cause significant changes in water mobility that is greater for stable hydration states and reduced for intermediate separations. By studying pyrophyllite with and without external water we reveal that long-range electrostatic forces apply a restraining effect upon interlayer water mobility. Our findings are relevant for broad range of confining nanostructures with walls thin enough to permit long-range interactions that could affect the mobility of confined solvent molecules and solute species.

  5. Long-Range Interactions Restrict Water Transport in Pyrophyllite Interlayers

    NASA Astrophysics Data System (ADS)

    Zarzycki, Piotr; Gilbert, Benjamin

    2016-04-01

    Water diffusion within smectite clay interlayers is reduced by confinement and hence is highly determined by the interlayer spacings that are adopted during swelling. However, a molecular understanding of the short- and long-range forces governing interlayer water structure and dynamics is lacking. Using molecular dynamics simulations of water intercalated between pyrophyllite (smectite prototype) layers we provide a detailed picture of the variation of interlayered water mobility accompanying smectite expansion. Subtle changes in hydrogen bond network structure cause significant changes in water mobility that is greater for stable hydration states and reduced for intermediate separations. By studying pyrophyllite with and without external water we reveal that long-range electrostatic forces apply a restraining effect upon interlayer water mobility. Our findings are relevant for broad range of confining nanostructures with walls thin enough to permit long-range interactions that could affect the mobility of confined solvent molecules and solute species.

  6. Long-Range Interactions Restrict Water Transport in Pyrophyllite Interlayers

    DOE PAGES

    Zarzycki, Piotr; Gilbert, Benjamin

    2016-04-27

    Water diffusion within smectite clay interlayers is reduced by confinement and hence is highly determined by the interlayer spacings that are adopted during swelling. However, a molecular understanding of the short-and long-range forces governing interlayer water structure and dynamics is lacking. Using molecular dynamics simulations of water intercalated between pyrophyllite (smectite prototype) layers we provide a detailed picture of the variation of interlayered water mobility accompanying smectite expansion. Subtle changes in hydrogen bond network structure cause significant changes in water mobility that is greater for stable hydration states and reduced for intermediate separations. By studying pyrophyllite with and without externalmore » water we reveal that long-range electrostatic forces apply a restraining effect upon interlayer water mobility. Our findings are relevant for broad range of confining nanostructures with walls thin enough to permit long-range interactions that could affect the mobility of confined solvent molecules and solute species.« less

  7. Long-Range Interactions Restrict Water Transport in Pyrophyllite Interlayers

    PubMed Central

    Zarzycki, Piotr; Gilbert, Benjamin

    2016-01-01

    Water diffusion within smectite clay interlayers is reduced by confinement and hence is highly determined by the interlayer spacings that are adopted during swelling. However, a molecular understanding of the short- and long-range forces governing interlayer water structure and dynamics is lacking. Using molecular dynamics simulations of water intercalated between pyrophyllite (smectite prototype) layers we provide a detailed picture of the variation of interlayered water mobility accompanying smectite expansion. Subtle changes in hydrogen bond network structure cause significant changes in water mobility that is greater for stable hydration states and reduced for intermediate separations. By studying pyrophyllite with and without external water we reveal that long-range electrostatic forces apply a restraining effect upon interlayer water mobility. Our findings are relevant for broad range of confining nanostructures with walls thin enough to permit long-range interactions that could affect the mobility of confined solvent molecules and solute species. PMID:27118164

  8. Pivotal role of hMT+ in long-range disambiguation of interhemispheric bistable surface motion.

    PubMed

    Duarte, João Valente; Costa, Gabriel Nascimento; Martins, Ricardo; Castelo-Branco, Miguel

    2017-10-01

    It remains an open question whether long-range disambiguation of ambiguous surface motion can be achieved in early visual cortex or instead in higher level regions, which concerns object/surface segmentation/integration mechanisms. We used a bistable moving stimulus that can be perceived as a pattern comprehending both visual hemi-fields moving coherently downward or as two widely segregated nonoverlapping component objects (in each visual hemi-field) moving separately inward. This paradigm requires long-range integration across the vertical meridian leading to interhemispheric binding. Our fMRI study (n = 30) revealed a close relation between activity in hMT+ and perceptual switches involving interhemispheric segregation/integration of motion signals, crucially under nonlocal conditions where components do not overlap and belong to distinct hemispheres. Higher signal changes were found in hMT+ in response to spatially segregated component (incoherent) percepts than to pattern (coherent) percepts. This did not occur in early visual cortex, unlike apparent motion, which does not entail surface segmentation. We also identified a role for top-down mechanisms in state transitions. Deconvolution analysis of switch-related changes revealed prefrontal, insula, and cingulate areas, with the right superior parietal lobule (SPL) being particularly involved. We observed that directed influences could emerge either from left or right hMT+ during bistable motion integration/segregation. SPL also exhibited significant directed functional connectivity with hMT+, during perceptual state maintenance (Granger causality analysis). Our results suggest that long-range interhemispheric binding of ambiguous motion representations mainly reflect bottom-up processes from hMT+ during perceptual state maintenance. In contrast, state transitions maybe influenced by high-level regions such as the SPL. Hum Brain Mapp 38:4882-4897, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley

  9. Holographic thermalization with initial long range correlation

    DOE PAGES

    Lin, Shu

    2016-01-19

    Here, we studied the evolution of the Wightman correlator in a thermalizing state modeled by AdS3-Vaidya background. A prescription was given for calculating the Wightman correlator in coordinate space without using any approximation. For equal-time correlator , we obtained an enhancement factor v2 due to long range correlation present in the initial state. This was missed by previous studies based on geodesic approximation. Moreover, we found that the long range correlation in initial state does not lead to significant modification to thermalization time as compared to known results with generic initial state. We also studied the spatially integrated Wightman correlatormore » and showed evidence on the distinction between long distance and small momentum physics for an out-of-equilibrium state. We also calculated the radiation spectrum of particles weakly coupled to O and found that lower frequency mode approaches thermal spectrum faster than high frequency mode.« less

  10. Long-range correlations in nucleotide sequences

    NASA Astrophysics Data System (ADS)

    Peng, C.-K.; Buldyrev, S. V.; Goldberger, A. L.; Havlin, S.; Sciortino, F.; Simons, M.; Stanley, H. E.

    1992-03-01

    DNA SEQUENCES have been analysed using models, such as an it-step Markov chain, that incorporate the possibility of short-range nucleotide correlations1. We propose here a method for studying the stochastic properties of nucleotide sequences by constructing a 1:1 map of the nucleotide sequence onto a walk, which we term a 'DNA walk'. We then use the mapping to provide a quantitative measure of the correlation between nucleotides over long distances along the DNA chain. Thus we uncover in the nucleotide sequence a remarkably long-range power law correlation that implies a new scale-invariant property of DNA. We find such long-range correlations in intron-containing genes and in nontranscribed regulatory DNA sequences, but not in complementary DNA sequences or intron-less genes.

  11. Gemini: A long-range cargo transport

    NASA Technical Reports Server (NTRS)

    1994-01-01

    The proposed Gemini, a long-range cargo transport, is designed as a high capacity, dedicated cargo transporter of 8'x8'x20' inter-modal containers, and long-range design. These requirements will result in a design that is larger than any existing aircraft. Due to the size, a conventional configuration would result in an aircraft unable to operate economically at existing airports. It is necessary to design for a minimum possible empty weight, wingspan, and landing gear track. After considering both a single fuselage biplane and a double fuselage biplane configuration, the design team choose the double fuselage biplane configuration. Both of these configuration choices result in a reduced wing root bending moment and subsequently in substantial savings in the wing weight. An overall decrease in the weight of the airplane, its systems, and fuel will be a direct result of the wing weight savings.

  12. Long-range correlations in nucleotide sequences

    NASA Technical Reports Server (NTRS)

    Peng, C. K.; Buldyrev, S. V.; Goldberger, A. L.; Havlin, S.; Sciortino, F.; Simons, M.; Stanley, H. E.

    1992-01-01

    DNA sequences have been analysed using models, such as an n-step Markov chain, that incorporate the possibility of short-range nucleotide correlations. We propose here a method for studying the stochastic properties of nucleotide sequences by constructing a 1:1 map of the nucleotide sequence onto a walk, which we term a 'DNA walk'. We then use the mapping to provide a quantitative measure of the correlation between nucleotides over long distances along the DNA chain. Thus we uncover in the nucleotide sequence a remarkably long-range power law correlation that implies a new scale-invariant property of DNA. We find such long-range correlations in intron-containing genes and in nontranscribed regulatory DNA sequences, but not in complementary DNA sequences or intron-less genes.

  13. Long-range correlations in nucleotide sequences

    NASA Technical Reports Server (NTRS)

    Peng, C. K.; Buldyrev, S. V.; Goldberger, A. L.; Havlin, S.; Sciortino, F.; Simons, M.; Stanley, H. E.

    1992-01-01

    DNA sequences have been analysed using models, such as an n-step Markov chain, that incorporate the possibility of short-range nucleotide correlations. We propose here a method for studying the stochastic properties of nucleotide sequences by constructing a 1:1 map of the nucleotide sequence onto a walk, which we term a 'DNA walk'. We then use the mapping to provide a quantitative measure of the correlation between nucleotides over long distances along the DNA chain. Thus we uncover in the nucleotide sequence a remarkably long-range power law correlation that implies a new scale-invariant property of DNA. We find such long-range correlations in intron-containing genes and in nontranscribed regulatory DNA sequences, but not in complementary DNA sequences or intron-less genes.

  14. Long Range Acoustic Communication in Deep Water

    DTIC Science & Technology

    2014-09-30

    Acoustic communication at long range in the ocean is challenging due to the substantial propagation loss, multipath delay spread , and channel...20 Hz in the upward refracting Arctic acoustic channel. However, the seafloor topography in the region of the Chukchi Plateau is very uneven over...which the depth was 600 m and thus the seafloor affected every mode of the ACOUS signal except for mode 1 which was confined to the upper 200 m. In April

  15. Bottom Interaction in Long Range Acoustic Propagation

    DTIC Science & Technology

    2009-09-30

    model calculations (RR, RSR, RBR, SRBR ray paths and the mode-like finale region), 2) deep shadow zone arrivals arising from the spread of energy below...arrivals near 75Hz were observed on bottom-mounted hydrophones in the shadow zone well below the SOFAR channel. Dushaw et al (1999) note: "This...explain the energy in the shadow zones: 1) energy is scattered from internal waves and fine structure in the ocean, or 2) long range sound propagation

  16. Long-range aircraft are in demand

    SciTech Connect

    Demeis, R.

    1991-05-01

    The overriding technological combinations that must be developed to provide for increased payload/long-range efficiency in commercial aircraft are discussed. The many requirements include: lighter structures, fuel efficiency, available engine thrust at optimum cruise altitude, and the relationship of lift, drag, and engine fuel efficiency to produce the greatest range when drag divided by speed is kept to a minimum. Attention is given to the various new ultra-high-bypass turbofans under development that approach the 100,000 lb thrust category with bypass ratios of better than 20/1.

  17. Fan-less long range alpha detector

    DOEpatents

    MacArthur, D.W.; Bounds, J.A.

    1994-05-10

    A fan-less long range alpha detector is disclosed which operates by using an electrical field between a signal plane and the surface or substance to be monitored for air ions created by collisions with alpha radiation. Without a fan, the detector can operate without the possibility of spreading dust and potential contamination into the atmosphere. A guard plane between the signal plane and the electrically conductive enclosure and maintained at the same voltage as the signal plane, reduces leakage currents. The detector can easily monitor soil, or other solid or liquid surfaces. 2 figures.

  18. NASA's Long-range Technology Goals

    NASA Technical Reports Server (NTRS)

    1990-01-01

    This document is part of the Final Report performed under contract NASW-3864, titled "NASA's Long-Range Technology Goals". The objectives of the effort were: To identify technologies whose development falls within NASA's capability and purview, and which have high potential for leapfrog advances in the national industrial posture in the 2005-2010 era. To define which of these technologies can also enable quantum jumps in the national space program. To assess mechanisms of interaction between NASA and industry constituencies for realizing the leapfrog technologies. This Volume details the findings pertaining to the advanced space-enabling technologies.

  19. Fan-less long range alpha detector

    DOEpatents

    MacArthur, Duncan W.; Bounds, John A.

    1994-01-01

    A fan-less long range alpha detector which operates by using an electrical field between a signal plane and the surface or substance to be monitored for air ions created by collisions with alpha radiation. Without a fan, the detector can operate without the possibility of spreading dust and potential contamination into the atmosphere. A guard plane between the signal plane and the electrically conductive enclosure and maintained at the same voltage as the signal plane, reduces leakage currents. The detector can easily monitor soil, or other solid or liquid surfaces.

  20. A criterion autoscheduler for long range planning

    NASA Technical Reports Server (NTRS)

    Sponsler, Jeffrey L.

    1994-01-01

    A constraint-based scheduling system called SPIKE is used to create long-term schedules for the Hubble Space Telescope. A meta-level scheduler called the Criterion Autoscheduler for Long range planning (CASL) was created to guide SPIKE's schedule generation according to the agenda of the planning scientists. It is proposed that sufficient flexibility exists in a schedule to allow high level planning heuristics to be applied without adversely affected crucial constraints such as spacecraft efficiency. This hypothesis is supported by test data which is described.

  1. Long-range energy transport in photosystem II.

    PubMed

    Roden, Jan J J; Bennett, Doran I G; Whaley, K Birgitta

    2016-06-28

    We simulate the long-range inter-complex electronic energy transfer in photosystem II-from the antenna complex, via a core complex, to the reaction center-using a non-Markovian (ZOFE) quantum master equation description that allows the electronic coherence involved in the energy transfer to be explicitly included at all length scales. This allows us to identify all locations where coherence is manifested and to further identify the pathways of the energy transfer in the full network of coupled chromophores using a description based on excitation probability currents. We investigate how the energy transfer depends on the initial excitation-localized, coherent initial excitation versus delocalized, incoherent initial excitation-and find that the overall energy transfer is remarkably robust with respect to such strong variations of the initial condition. To explore the importance of vibrationally enhanced transfer and to address the question of optimization in the system parameters, we systematically vary the strength of the coupling between the electronic and the vibrational degrees of freedom. We find that the natural parameters lie in a (broad) region that enables optimal transfer efficiency and that the overall long-range energy transfer on a ns time scale appears to be very robust with respect to variations in the vibronic coupling of up to an order of magnitude. Nevertheless, vibrationally enhanced transfer appears to be crucial to obtain a high transfer efficiency, with the latter falling sharply for couplings outside the optimal range. Comparison of our full quantum simulations to results obtained with a "classical" rate equation based on a modified-Redfield/generalized-Förster description previously used to simulate energy transfer dynamics in the entire photosystem II complex shows good agreement for the overall time scales of excitation energy transport.

  2. Long-range energy transport in photosystem II

    NASA Astrophysics Data System (ADS)

    Roden, Jan J. J.; Bennett, Doran I. G.; Whaley, K. Birgitta

    2016-06-01

    We simulate the long-range inter-complex electronic energy transfer in photosystem II - from the antenna complex, via a core complex, to the reaction center - using a non-Markovian (ZOFE) quantum master equation description that allows the electronic coherence involved in the energy transfer to be explicitly included at all length scales. This allows us to identify all locations where coherence is manifested and to further identify the pathways of the energy transfer in the full network of coupled chromophores using a description based on excitation probability currents. We investigate how the energy transfer depends on the initial excitation - localized, coherent initial excitation versus delocalized, incoherent initial excitation - and find that the overall energy transfer is remarkably robust with respect to such strong variations of the initial condition. To explore the importance of vibrationally enhanced transfer and to address the question of optimization in the system parameters, we systematically vary the strength of the coupling between the electronic and the vibrational degrees of freedom. We find that the natural parameters lie in a (broad) region that enables optimal transfer efficiency and that the overall long-range energy transfer on a ns time scale appears to be very robust with respect to variations in the vibronic coupling of up to an order of magnitude. Nevertheless, vibrationally enhanced transfer appears to be crucial to obtain a high transfer efficiency, with the latter falling sharply for couplings outside the optimal range. Comparison of our full quantum simulations to results obtained with a "classical" rate equation based on a modified-Redfield/generalized-Förster description previously used to simulate energy transfer dynamics in the entire photosystem II complex shows good agreement for the overall time scales of excitation energy transport.

  3. Holographic thermalization with initial long range correlation

    SciTech Connect

    Lin, Shu

    2016-01-19

    Here, we studied the evolution of the Wightman correlator in a thermalizing state modeled by AdS3-Vaidya background. A prescription was given for calculating the Wightman correlator in coordinate space without using any approximation. For equal-time correlator , we obtained an enhancement factor v2 due to long range correlation present in the initial state. This was missed by previous studies based on geodesic approximation. Moreover, we found that the long range correlation in initial state does not lead to significant modification to thermalization time as compared to known results with generic initial state. We also studied the spatially integrated Wightman correlator and showed evidence on the distinction between long distance and small momentum physics for an out-of-equilibrium state. We also calculated the radiation spectrum of particles weakly coupled to O and found that lower frequency mode approaches thermal spectrum faster than high frequency mode.

  4. Long-range Order in Canary Song

    PubMed Central

    Markowitz, Jeffrey E.; Ivie, Elizabeth; Kligler, Laura; Gardner, Timothy J.

    2013-01-01

    Bird songs range in form from the simple notes of a Chipping Sparrow to the rich performance of the nightingale. Non-adjacent correlations can be found in the syntax of some birdsongs, indicating that the choice of what to sing next is determined not only by the current syllable, but also by previous syllables sung. Here we examine the song of the domesticated canary, a complex singer whose song consists of syllables, grouped into phrases that are arranged in flexible sequences. Phrases are defined by a fundamental time-scale that is independent of the underlying syllable duration. We show that the ordering of phrases is governed by long-range rules: the choice of what phrase to sing next in a given context depends on the history of the song, and for some syllables, highly specific rules produce correlations in song over timescales of up to ten seconds. The neural basis of these long-range correlations may provide insight into how complex behaviors are assembled from more elementary, stereotyped modules. PMID:23658509

  5. Long-range order in canary song.

    PubMed

    Markowitz, Jeffrey E; Ivie, Elizabeth; Kligler, Laura; Gardner, Timothy J

    2013-01-01

    Bird songs range in form from the simple notes of a Chipping Sparrow to the rich performance of the nightingale. Non-adjacent correlations can be found in the syntax of some birdsongs, indicating that the choice of what to sing next is determined not only by the current syllable, but also by previous syllables sung. Here we examine the song of the domesticated canary, a complex singer whose song consists of syllables, grouped into phrases that are arranged in flexible sequences. Phrases are defined by a fundamental time-scale that is independent of the underlying syllable duration. We show that the ordering of phrases is governed by long-range rules: the choice of what phrase to sing next in a given context depends on the history of the song, and for some syllables, highly specific rules produce correlations in song over timescales of up to ten seconds. The neural basis of these long-range correlations may provide insight into how complex behaviors are assembled from more elementary, stereotyped modules.

  6. Long Range Surface Plasmon Fluorescence Spectroscopy

    NASA Astrophysics Data System (ADS)

    Kasry, Amal; Knoll, Wolfgang

    2007-03-01

    Surface plasmon modes, excited at the two sides of a thin metal layer surrounded by two (nearly) identical dielectric media interact via the overlap of their electromagnetic fields. This overlap results in two new-coupled modes, a short and a long-range surface plasmon (LRSP). We demonstrate that combining the LRSP optics with fluorescence spectroscopy can result in a huge enhancement of the fluorescence signal due to the enhanced optical field of the LRSP at the metal dielectric interface, and to its increased evanescent depth into the analyte. This was demonstrated for the detection of the fluorescence intensity of chromophore labeled protein bound to the surface sensor. Beside that, some fundamentals were studied leading to some interesting difference between SPFS and LRSPFS.

  7. Long range inductive power transfer system

    NASA Astrophysics Data System (ADS)

    Lawson, James; Pinuela, Manuel; Yates, David C.; Lucyszyn, Stepan; Mitcheson, Paul D.

    2013-12-01

    We report upon a recently developed long range inductive power transfer system (IPT) designed to power remote sensors with mW level power consumption at distances up to 7 m. In this paper an inductive link is established between a large planar (1 × 1 m) transmit coil (Tx) and a small planer (170 × 170 mm) receiver coil (Rx), demonstrating the viability of highly asymmetrical coil configurations that real-world applications such as sensor networks impose. High Q factor Tx and Rx coils required for viable power transfer efficiencies over such distances are measured using a resonant method. The applicability of the Class-E amplifier in very low magnetic coupling scenarios and at the high frequencies of operation required for high Q operation is demonstrated by its usage as the Tx coil driver.

  8. Long-range polarimetric imaging through fog.

    PubMed

    Fade, Julien; Panigrahi, Swapnesh; Carré, Anthony; Frein, Ludovic; Hamel, Cyril; Bretenaker, Fabien; Ramachandran, Hema; Alouini, Mehdi

    2014-06-20

    We report an experimental implementation of long-range polarimetric imaging through fog over kilometric distance in real field atmospheric conditions. An incoherent polarized light source settled on a telecommunication tower is imaged at a distance of 1.3 km with a snapshot polarimetric camera including a birefringent Wollaston prism, allowing simultaneous acquisition of two images along orthogonal polarization directions. From a large number of acquisitions datasets and under various environmental conditions (clear sky/fog/haze, day/night), we compare the efficiency of using polarized light for source contrast increase with different signal representations (intensity, polarimetric difference, polarimetric contrast, etc.). With the limited-dynamics detector used, a maximum fourfold increase in contrast was demonstrated under bright background illumination using polarimetric difference image.

  9. Percolation with long-range correlated disorder.

    PubMed

    Schrenk, K J; Posé, N; Kranz, J J; van Kessenich, L V M; Araújo, N A M; Herrmann, H J

    2013-11-01

    Long-range power-law correlated percolation is investigated using Monte Carlo simulations. We obtain several static and dynamic critical exponents as functions of the Hurst exponent H, which characterizes the degree of spatial correlation among the occupation of sites. In particular, we study the fractal dimension of the largest cluster and the scaling behavior of the second moment of the cluster size distribution, as well as the complete and accessible perimeters of the largest cluster. Concerning the inner structure and transport properties of the largest cluster, we analyze its shortest path, backbone, red sites, and conductivity. Finally, bridge site growth is also considered. We propose expressions for the functional dependence of the critical exponents on H.

  10. Fe-based long range ordered alloys

    DOEpatents

    Liu, Chain T; Inouye, Henry; Schaffhauser, Anthony C.

    1980-01-01

    Malleable long range ordered alloys having high critical ordering temperatures exist in the V(Co,Fe).sub.3 and V(Co,Fe,Ni).sub.3 system having the composition comprising by weight 22-23% V, 35-50% Fe, 0-22% Co and 19-40% Ni with an electron density no greater than 8.00. Excellent high temperature properties occur in alloys having compositions comprising by weight 22-23% V, 35-45% Fe, 0-10% Co, 25-35% Ni; 22-23% V, 28-33% Ni and the remainder Fe; and 22-23% V, 19-22% Ni, 19-22% Co and the remainder Fe. The alloys are fabricable by casting, deforming and annealing for sufficient time to provide ordered structure.

  11. Fe-based long range ordered alloys

    DOEpatents

    Liu, C.T.

    Malleable long range ordered alloys with high critical ordering temperatures exist in the V(Co,Fe)/sub 3/ and V(Co,Fe,Ni)/sub 3/ system. The composition comprising by weight 22 to 23% V, 35 to 50% Fe, 0 to 22% Co and 19 to 40% Ni with an electron density no greater than 8.00. Excellent high temperature properties occur in alloys having compositions comprising by weight 22 to 23% V, 35 to 45% Fe, 0 to 10% Co, 25 to 35% Ni; 22 to 23% V, 28 to 33% Ni and the remainder Fe; and 22 to 23% V, 19 to 22% Co and the remainder Fe. The alloys are fabricable by casting, deforming and annealing for sufficient time to provide ordered structure.

  12. A Long-Range Video Observation Post

    SciTech Connect

    Arlowe, D.

    1995-07-01

    The Long Range Video Observation Post (LRVOP) Project is a cooperative effort between the US and a Middle Eastern country to develop an improved version of their current video observation post. This project is part of a larger effort to cooperatively develop anti-terrorist technology. This particular equipment is required to facilitate the recording and identification of humans at a range of 1000 meters in day-light and 500 meters at night. The project objective was to take advantage of recent advances in camera technology, recorders, and image processing to provide an significant increase in performance with only a minimum increase in size, weight, and cost. The goal of the project was to convert the users general needs and desires into specific requirements that could be bid on by several companies. This paper covers the specific performance requirements, generally describe the components that might be used, and concentrate on describing the more difficult issues and technical challenges.

  13. Long-range hybrid ridge and trench plasmonic waveguides

    SciTech Connect

    Bian, Yusheng; Gong, Qihuang

    2014-06-23

    We report a class of long-range hybrid plasmon polariton waveguides capable of simultaneously achieving low propagation loss and tight field localization at telecommunication wavelength. The symmetric (quasi-symmetric) hybrid configurations featuring high-refractive-index-contrast near the non-uniform metallic nanostructures enable significantly improved optical performance over conventional hybrid waveguides, exhibiting considerably longer propagation distances and dramatically enhanced figure of merits for similar degrees of confinement. Compared to their traditional long-range plasmonic counterparts, the proposed hybrid waveguides put much less stringent requirements on index-matching conditions, demonstrating nice performance under a wide range of physical dimensions and robust characteristics against certain fabrication imperfections. Studies concerning crosstalk between adjacent identical waveguides further reveal their potential for photonic integrations. In addition, alternative configurations with comparable guiding properties to the structures in our case studies are also proposed, which can potentially serve as attractive prototypes for numerous high-performance nanophotonic components.

  14. Contactless nonlinear optics mediated by long-range Rydberg interactions

    NASA Astrophysics Data System (ADS)

    Busche, Hannes; Huillery, Paul; Ball, Simon W.; Ilieva, Teodora; Jones, Matthew P. A.; Adams, Charles S.

    2017-07-01

    In conventional nonlinear optics, linear quantum optics, and cavity quantum electrodynamics to create effective photon-photon interactions photons must have, at one time, interacted with matter inside a common medium. In contrast, in Rydberg quantum optics, optical photons are coherently and reversibly mapped onto collective atomic Rydberg excitations, giving rise to dipole-mediated effective photon-photon interactions that are long range. Consequently, a spatial overlap between the light modes is no longer required. We demonstrate such a contactless coupling between photons stored as collective Rydberg excitations in spatially separate optical media. The potential induced by each photon modifies the retrieval mode of its neighbour, leading to correlations between them. We measure these correlations as a function of interaction strength, distance and storage time, demonstrating an effective interaction between photons separated by 15 times their wavelength. Contactless effective photon-photon interactions are relevant for scalable multichannel photonic devices and the study of strongly correlated many-body dynamics using light.

  15. Long-Range Atlantic Acoustic Multipath Identification.

    NASA Astrophysics Data System (ADS)

    Legters, George Richard

    Multipath data from three long-range (900 kilometers) transmissions are examined. Two of the transmissions follow similar tracks, but are separated by the Gulf Stream at the receiving end. The third, which is substantially free of Gulf Stream influence, has been intensively studied Spiesberger et al. (J. Acoust. Soc. Am. 67, 2011-7 (1980)). A package of computer algorithms based on the geometrical optics approximation was developed to model and analyze the acoustic transmission. Path identification with ray calculations was attempted for the two transmission channels exhibiting stable multipath with success for the major features of the path structures. Excessive smoothing of the sound speed profile which eliminates the influence of the Atlantic eighteen-degree celsius water mass in the upper layers is shown to degrade the identification of early arrivals. The slight curvature of the ocean sound speed profile around four kilometers of depth also was critical to early arrival identification. The effect of weak range dependence was small while the effect of a gradual sloping bottom near one receiver was significant.

  16. Long range position and Orientation Tracking System

    SciTech Connect

    Armstrong, G.A.; Jansen, J.F.; Burks, B.L.

    1996-02-01

    The long range Position and Orientation Tracking System is an active triangulation-based system that is being developed to track a target to a resolution of 6.35 mm (0.25 in.) and 0.009{degrees}(32.4 arcseconds) over a range of 13.72 m (45 ft.). The system update rate is currently set at 20 Hz but can be increased to 100 Hz or more. The tracking is accomplished by sweeping two pairs of orthogonal line lasers over infrared (IR) sensors spaced with known geometry with respect to one another on the target (the target being a rigid body attached to either a remote vehicle or a remote manipulator arm). The synchronization and data acquisition electronics correlates the time that an IR sensor has been hit by one of the four lasers and the angle of the respective mirror at the time of the hit. This information is combined with the known geometry of the IR sensors on the target to determine position and orientation of the target. This method has the advantage of allowing the target to be momentarily lost due to occlusions and then reacquired without having to return the target to a known reference point. The system also contains a camera with operator controlled lighting in each pod that allows the target to be continuously viewed from either pod, assuming their are no occlusions.

  17. Long Range Infrared Surveillance System (LRIRSS)

    NASA Astrophysics Data System (ADS)

    Garcia, Gregg W.

    1987-09-01

    The contract requirement for the LRIRSS program was to design, fabricate, test, and deliver infrared (IR) surveillance systems capable of target detection and recognition at extended ranges. Several significant technical advancements were made during the course of the program. The twenty three inch primary reflecting surface had to be of aluminum due to thermal and weight considerations. This was accomplished through the use of diamond point turned aluminum. The IR and laser receivers are active simultaneously; this has been achieved through the incorporation of a "chopping" mirror that time shares the main aperture between the FLIR and CO2 laser receivers. In addition, the laser had to be eye-safe at the transmitter exit aperture. The use of a single pulse Carbon Dioxide (CO2) laser has met the requirement, and is certified by the US Army Environmental Hygiene Agency in Study No. 25-42-0335-85. The major technical challenges have been met, as well as several minor difficulties that arose during the execution of the effort. All hardware has been delivered to the Government in accord with the contractual schedule. NOMENCLATURE CO2 Carbon Dioxide CPU Central Processing Unit FLIR Forward Looking Infrared FOV Field of View IFOV Instantaneous Field of View IR Infrared LRF Laser Rangefinder LRIRSS Long Range Infrared Surveillance System PCB Printed Circuit Board

  18. A Long-Range Precision Ranging System

    NASA Technical Reports Server (NTRS)

    Easterling, Mahlon

    1961-01-01

    A technique is presented that may be used for precision real-time continuous range measuring at long ranges. The technique uses a carrier that is phase modulated by a pseudo-random binary sequence. The characteristics of the sequence that make it acquirable are discussed. The general form of a receiver capable of tracking the carrier is given and is shown to be a kind of phase-locked loop. A two-loop system capable of tracking a pseudo-random sequence and its clock is given. The combination of the receiver and the sequence tracking system form a ranging receiver. The power division necessary between the carrier and the sidebands is shown to be determined by the noise bandwidths of the two tracking systems. The bandwidths necessary for tracking space probes and Earth satellites are given and some experiments in radar-tracking Earth satellites are described. Based on these experiments, estimates are made of the useful range of such a system in tracking space probes.

  19. Long-range correlations in self-gravitating N-body systems

    NASA Astrophysics Data System (ADS)

    Huber, D.; Pfenniger, D.

    2002-04-01

    Observed self-gravitating systems reveal often fragmented, non-equilibrium structures that feature characteristic long-range correlations. However, models accounting for non-linear structure growth are not always consistent with observations and a better understanding of self-gravitating N-body systems appears necessary. Because unstable gravitating systems are sensitive to non-gravitational perturbations, we study the effect of different dissipative factors as well as different small and large scale boundary conditions on idealized N-body systems. We find, in the interval of negative specific heat, equilibrium properties differing from theoretical predictions made for gravo-thermal systems, substantiating the importance of microscopic physics and the lack of consistent theoretical tools to describe self-gravitating gas. Also, in the interval of negative specific heat, yet outside of equilibrium, unforced systems fragment and establish transient long-range correlations. The strength of these correlations depends on the degree of granularity, which shows that the mass and force resolution should be coherent. Finally, persistent correlations appear in model systems subject to an energy flow.

  20. Observation of prethermalization in long-range interacting spin chains

    PubMed Central

    Neyenhuis, Brian; Zhang, Jiehang; Hess, Paul W.; Smith, Jacob; Lee, Aaron C.; Richerme, Phil; Gong, Zhe-Xuan; Gorshkov, Alexey V.; Monroe, Christopher

    2017-01-01

    Although statistical mechanics describes thermal equilibrium states, these states may or may not emerge dynamically for a subsystem of an isolated quantum many-body system. For instance, quantum systems that are near-integrable usually fail to thermalize in an experimentally realistic time scale, and instead relax to quasi-stationary prethermal states that can be described by statistical mechanics, when approximately conserved quantities are included in a generalized Gibbs ensemble (GGE). We experimentally study the relaxation dynamics of a chain of up to 22 spins evolving under a long-range transverse-field Ising Hamiltonian following a sudden quench. For sufficiently long-range interactions, the system relaxes to a new type of prethermal state that retains a strong memory of the initial conditions. However, the prethermal state in this case cannot be described by a standard GGE; it rather arises from an emergent double-well potential felt by the spin excitations. This result shows that prethermalization occurs in a broader context than previously thought, and reveals new challenges for a generic understanding of the thermalization of quantum systems, particularly in the presence of long-range interactions. PMID:28875166

  1. Segmentation of time series with long-range fractal correlations

    NASA Astrophysics Data System (ADS)

    Bernaola-Galván, P.; Oliver, J. L.; Hackenberg, M.; Coronado, A. V.; Ivanov, P. Ch.; Carpena, P.

    2012-06-01

    Segmentation is a standard method of data analysis to identify change-points dividing a nonstationary time series into homogeneous segments. However, for long-range fractal correlated series, most of the segmentation techniques detect spurious change-points which are simply due to the heterogeneities induced by the correlations and not to real nonstationarities. To avoid this oversegmentation, we present a segmentation algorithm which takes as a reference for homogeneity, instead of a random i.i.d. series, a correlated series modeled by a fractional noise with the same degree of correlations as the series to be segmented. We apply our algorithm to artificial series with long-range correlations and show that it systematically detects only the change-points produced by real nonstationarities and not those created by the correlations of the signal. Further, we apply the method to the sequence of the long arm of human chromosome 21, which is known to have long-range fractal correlations. We obtain only three segments that clearly correspond to the three regions of different G + C composition revealed by means of a multi-scale wavelet plot. Similar results have been obtained when segmenting all human chromosome sequences, showing the existence of previously unknown huge compositional superstructures in the human genome.

  2. Segmentation of time series with long-range fractal correlations

    PubMed Central

    Bernaola-Galván, P.; Oliver, J.L.; Hackenberg, M.; Coronado, A.V.; Ivanov, P.Ch.; Carpena, P.

    2012-01-01

    Segmentation is a standard method of data analysis to identify change-points dividing a nonstationary time series into homogeneous segments. However, for long-range fractal correlated series, most of the segmentation techniques detect spurious change-points which are simply due to the heterogeneities induced by the correlations and not to real nonstationarities. To avoid this oversegmentation, we present a segmentation algorithm which takes as a reference for homogeneity, instead of a random i.i.d. series, a correlated series modeled by a fractional noise with the same degree of correlations as the series to be segmented. We apply our algorithm to artificial series with long-range correlations and show that it systematically detects only the change-points produced by real nonstationarities and not those created by the correlations of the signal. Further, we apply the method to the sequence of the long arm of human chromosome 21, which is known to have long-range fractal correlations. We obtain only three segments that clearly correspond to the three regions of different G + C composition revealed by means of a multi-scale wavelet plot. Similar results have been obtained when segmenting all human chromosome sequences, showing the existence of previously unknown huge compositional superstructures in the human genome. PMID:23645997

  3. Observation of prethermalization in long-range interacting spin chains.

    PubMed

    Neyenhuis, Brian; Zhang, Jiehang; Hess, Paul W; Smith, Jacob; Lee, Aaron C; Richerme, Phil; Gong, Zhe-Xuan; Gorshkov, Alexey V; Monroe, Christopher

    2017-08-01

    Although statistical mechanics describes thermal equilibrium states, these states may or may not emerge dynamically for a subsystem of an isolated quantum many-body system. For instance, quantum systems that are near-integrable usually fail to thermalize in an experimentally realistic time scale, and instead relax to quasi-stationary prethermal states that can be described by statistical mechanics, when approximately conserved quantities are included in a generalized Gibbs ensemble (GGE). We experimentally study the relaxation dynamics of a chain of up to 22 spins evolving under a long-range transverse-field Ising Hamiltonian following a sudden quench. For sufficiently long-range interactions, the system relaxes to a new type of prethermal state that retains a strong memory of the initial conditions. However, the prethermal state in this case cannot be described by a standard GGE; it rather arises from an emergent double-well potential felt by the spin excitations. This result shows that prethermalization occurs in a broader context than previously thought, and reveals new challenges for a generic understanding of the thermalization of quantum systems, particularly in the presence of long-range interactions.

  4. Long-range dismount activity classification: LODAC

    NASA Astrophysics Data System (ADS)

    Garagic, Denis; Peskoe, Jacob; Liu, Fang; Cuevas, Manuel; Freeman, Andrew M.; Rhodes, Bradley J.

    2014-06-01

    Continuous classification of dismount types (including gender, age, ethnicity) and their activities (such as walking, running) evolving over space and time is challenging. Limited sensor resolution (often exacerbated as a function of platform standoff distance) and clutter from shadows in dense target environments, unfavorable environmental conditions, and the normal properties of real data all contribute to the challenge. The unique and innovative aspect of our approach is a synthesis of multimodal signal processing with incremental non-parametric, hierarchical Bayesian machine learning methods to create a new kind of target classification architecture. This architecture is designed from the ground up to optimally exploit correlations among the multiple sensing modalities (multimodal data fusion) and rapidly and continuously learns (online self-tuning) patterns of distinct classes of dismounts given little a priori information. This increases classification performance in the presence of challenges posed by anti-access/area denial (A2/AD) sensing. To fuse multimodal features, Long-range Dismount Activity Classification (LODAC) develops a novel statistical information theoretic approach for multimodal data fusion that jointly models multimodal data (i.e., a probabilistic model for cross-modal signal generation) and discovers the critical cross-modal correlations by identifying components (features) with maximal mutual information (MI) which is efficiently estimated using non-parametric entropy models. LODAC develops a generic probabilistic pattern learning and classification framework based on a new class of hierarchical Bayesian learning algorithms for efficiently discovering recurring patterns (classes of dismounts) in multiple simultaneous time series (sensor modalities) at multiple levels of feature granularity.

  5. The long range transport of sulfurous aerosol to Scandinavia

    SciTech Connect

    Ottar, B.

    1980-01-01

    Results of the LRTAP program and other European studies are discussed which show that considerable long-range transport of air pollutants from the UK and central Europe to Scandinavia occurs. Data are examined which reveal that the sulfate deposition pattern in Scandinavia is largely governed by precipitation and wind direction and that sulfates deposition reaches maximum values of 3 to 5 metric tons/sq km in southern Scandinavia. The contribution from precipitation is found to outweigh the dry deposition, particularly in southern Norway.

  6. Incoherent shock waves in long-range optical turbulence

    NASA Astrophysics Data System (ADS)

    Xu, G.; Garnier, J.; Faccio, D.; Trillo, S.; Picozzi, A.

    2016-10-01

    Considering the nonlinear Schrödinger (NLS) equation as a representative model, we report a unified presentation of different forms of incoherent shock waves that emerge in the long-range interaction regime of a turbulent optical wave system. These incoherent singularities can develop either in the temporal domain through a highly noninstantaneous nonlinear response, or in the spatial domain through a highly nonlocal nonlinearity. In the temporal domain, genuine dispersive shock waves (DSW) develop in the spectral dynamics of the random waves, despite the fact that the causality condition inherent to the response function breaks the Hamiltonian structure of the NLS equation. Such spectral incoherent DSWs are described in detail by a family of singular integro-differential kinetic equations, e.g. Benjamin-Ono equation, which are derived from a nonequilibrium kinetic formulation based on the weak Langmuir turbulence equation. In the spatial domain, the system is shown to exhibit a large scale global collective behavior, so that it is the fluctuating field as a whole that develops a singularity, which is inherently an incoherent object made of random waves. Despite the Hamiltonian structure of the NLS equation, the regularization of such a collective incoherent shock does not require the formation of a DSW - the regularization is shown to occur by means of a different process of coherence degradation at the shock point. We show that the collective incoherent shock is responsible for an original mechanism of spontaneous nucleation of a phase-space hole in the spectrogram dynamics. The robustness of such a phase-space hole is interpreted in the light of incoherent dark soliton states, whose different exact solutions are derived in the framework of the long-range Vlasov formalism.

  7. Long-Range Planning. School Districts Prepare for the Future.

    ERIC Educational Resources Information Center

    Hart, Thomas E.

    1988-01-01

    Long-range planning is becoming increasingly important for educators in today's rapidly changing society. This bulletin accordingly presents a step-by-step model for school districts to use in developing and successfully implementing a long-range plan. Chapter 1 introduces long-range planning and suggests ways of getting district personnel…

  8. Deep seafloor arrivals in long range ocean acoustic propagation.

    PubMed

    Stephen, Ralph A; Bolmer, S Thompson; Udovydchenkov, Ilya A; Worcester, Peter F; Dzieciuch, Matthew A; Andrew, Rex K; Mercer, James A; Colosi, John A; Howe, Bruce M

    2013-10-01

    Ocean bottom seismometer observations at 5000 m depth during the long-range ocean acoustic propagation experiment in the North Pacific in 2004 show robust, coherent, late arrivals that are not readily explained by ocean acoustic propagation models. These "deep seafloor" arrivals are the largest amplitude arrivals on the vertical particle velocity channel for ranges from 500 to 3200 km. The travel times for six (of 16 observed) deep seafloor arrivals correspond to the sea surface reflection of an out-of-plane diffraction from a seamount that protrudes to about 4100 m depth and is about 18 km from the receivers. This out-of-plane bottom-diffracted surface-reflected energy is observed on the deep vertical line array about 35 dB below the peak amplitude arrivals and was previously misinterpreted as in-plane bottom-reflected surface-reflected energy. The structure of these arrivals from 500 to 3200 km range is remarkably robust. The bottom-diffracted surface-reflected mechanism provides a means for acoustic signals and noise from distant sources to appear with significant strength on the deep seafloor.

  9. Long-range correlation and market segmentation in bond market

    NASA Astrophysics Data System (ADS)

    Wang, Zhongxing; Yan, Yan; Chen, Xiaosong

    2017-09-01

    This paper investigates the long-range auto-correlations and cross-correlations in bond market. Based on Detrended Moving Average (DMA) method, empirical results present a clear evidence of long-range persistence that exists in one year scale. The degree of long-range correlation related to maturities has an upward tendency with a peak in short term. These findings confirm the expectations of fractal market hypothesis (FMH). Furthermore, we have developed a method based on a complex network to study the long-range cross-correlation structure and applied it to our data, and found a clear pattern of market segmentation in the long run. We also detected the nature of long-range correlation in the sub-period 2007-2012 and 2011-2016. The result from our research shows that long-range auto-correlations are decreasing in the recent years while long-range cross-correlations are strengthening.

  10. Fingerprint of local disorder in long range ordered isometric pyrochlores.

    PubMed

    Martel, Laura; Naji, Mohamed; Popa, Karin; Vigier, Jean-François; Somers, Joseph

    2017-09-25

    The detailed characterization of local order and disorder in isometric A2B2O7 crystalline pyrochlores is of significant importance in view of their wide range and sensitive technological applications. Nevertheless, much remains to be understood concerning their atomic scale structures. Here we specifically pinpoint local order and disorder in four stoichiometric Ln2Zr2O7 (Ln = La, Nd, Sm and Eu) pyrochlores using a combination of three standard easily available laboratory techniques: XRD, (17)O solid-state MAS NMR and Raman spectroscopy. The evolution of the oxygen sub-lattice identifies specific features (extra (17)O NMR signals and Raman bands) which undoubtedly reveal local oxygen order and disorder in these stoichiometric long range ordered crystalline pyrochlores. These results complete the understanding of the atomic scale in these stoichiometric pyrochlores necessitating the need for new microscopic structural models.

  11. Can We Trust Long-Range Weather Forecasts ?

    NASA Astrophysics Data System (ADS)

    Mailier, Pascal

    2010-05-01

    Long-range weather forecasts are widely used in key sectors of the economy, but too often their properties and limitations are not understood well enough. This poster reviews the characteristics, methods and reliability of long-range weather forecasts, making recommendations regarding their use and quality assessment. Despite their limited skill, long-range weather forecasts can still be a valuable tool for managing weather risk provided the necessary caution is exercised.

  12. Long Range Facilities Planning Plan Guide Lines. Volume 1

    DTIC Science & Technology

    1982-04-01

    Maritime Administration invited Richard M. Muther to address the group on the subject of long range facility planning. Atlanta, Georgia. by MARAD was...NASSCO submitted a contract proposal to MARAD for cost sharing the development of NASSCO’s Long Range Facility Plan. Richard M. Muther addressed...given from United States A week-long seminar sponsored to train facility planners shipyards in the Muther tech- niques of long range facility planning

  13. Long Range Correlation of Hydrophilicity and Flexibility Along the Hemoglobin Chain

    SciTech Connect

    Craciun, D.; Isvoran, A.; Avram, N. M.

    2010-08-04

    Within this study, we reveal the long range correlation concerning hydrophilicity and flexibility along sequences of hemoglobins belonging to different organisms and we compare them with the long range correlations properties obtained for other protein families. For all hemoglobins considered, we investigate two discrete spatial series: the hydrophilicity and flexibility respectively. We apply the nonlinear analysis methods to analyze the two spatial series by calculating the spectral coefficient {beta}, the scaling exponent {alpha} and Hurst exponent H. The obtained values for the mentioned coefficients suggest long range correlation within the analyzed sequences of hemoglobins in good agreement with those obtained for the calcium binding proteins and hydrolases.

  14. 76 FR 77300 - Alaska Federal Lands Long Range Transportation Plan

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-12

    ... Federal Highway Administration Alaska Federal Lands Long Range Transportation Plan AGENCY: Federal Highway.... SUMMARY: The Federal Highway Administration, along with the Bureau of Land Management, Fish and Wildlife... Lands Long Range Transportation Plans (LRTP) for public review and comment. The draft plans outline a...

  15. Long-range attraction in aqueous colloidal suspensions

    NASA Astrophysics Data System (ADS)

    Zhao, Qing; Coult, Jason; Pollack, Gerald H.

    2010-11-01

    Long-range attractions in aqueous suspensions were observed between polymeric microspheres and also between microspheres and a gel bead. Attractive displacements were consistently seen even between like-charged entities, and they were observed over spans as large as 2 mm. Such behaviors are unexpected, and may reside in a long-range attraction mechanism.

  16. Long-range Antiferromagnetic Order in [MnTe/ZnTe] Superlattices

    NASA Astrophysics Data System (ADS)

    Rhyne, J.; Lin, J.; Furdyna, J.; Giebultowicz, T.

    1997-03-01

    Long range antiferromagnetic order has been found in epitaxially-grown superlattices of [(MnTe)_x/(ZnTe)_y] with thin ZnTe interlayers (e.g, y=3D4-6 monolayers) and MnTe layer thicknesses x =3D 10 and 20. Previous studies(T.M. Giebultowicz, P. Klosowski, N. Samarth, H. Luo, J. K. Furdyna, and J.J. Rhyne, Phys. Rev. B 48), 12817 (1993). of [MnTe/ZnTe] superlattices with thicker ZnTe interlayers (e.g., y=3D18) revealed antiferromagnetic order confined to single MnTe layers consistent with strong nearest-neighbor (NN) exchange and relatively weak higher-neighbor exchange. The thin ZnTe layer superlattices show an inphase antiferromagnetic interlayer coupling coherent across several bilayers with spin directions on adjacent MnTe layers determined by assuming "phantom" spins on the ZnTe layers with the same AFM order as the MnTe layers. As the temperature is raised, this ordering slowly transforms into an antiphase coupling with spin directions in alternate MnTe layers reversed from their low temperature structure. The magnetic scattered intensity from both co-existing phases vanishes at a common Neel temperature near 75 K.

  17. Long-range RNA pairings contribute to mutually exclusive splicing

    PubMed Central

    Yue, Yuan; Yang, Yun; Dai, Lanzhi; Cao, Guozheng; Chen, Ran; Hong, Weiling; Liu, Baoping; Shi, Yang; Meng, Yijun; Shi, Feng; Xiao, Mu; Jin, Yongfeng

    2016-01-01

    Mutually exclusive splicing is an important means of increasing the protein repertoire, by which the Down's syndrome cell adhesion molecule (Dscam) gene potentially generates 38,016 different isoforms in Drosophila melanogaster. However, the regulatory mechanisms remain obscure due to the complexity of the Dscam exon cluster. Here, we reveal a molecular model for the regulation of the mutually exclusive splicing of the serpent pre-mRNA based on competition between upstream and downstream RNA pairings. Such dual RNA pairings confer fine tuning of the inclusion of alternative exons. Moreover, we demonstrate that the splicing outcome of alternative exons is mediated in relative pairing strength-correlated mode. Combined comparative genomics analysis and experimental evidence revealed similar bidirectional structural architectures in exon clusters 4 and 9 of the Dscam gene. Our findings provide a novel mechanistic framework for the regulation of mutually exclusive splicing and may offer potentially applicable insights into long-range RNA–RNA interactions in gene regulatory networks. PMID:26554032

  18. Long Range Chiral Imprinting of Cu(110) by Tartaric Acid

    SciTech Connect

    Lawton, T J; Pushkarev, V; Wei, D; Lucci, F R; Sholl, D S; Gellman, A J; Sykes, E C. H.

    2013-10-31

    Restructuring of metals by chiral molecules represents an important route to inducing and controlling enantioselective surface chemistry. Tartaric acid adsorption on Cu(110) has served as a useful system for understanding many aspects of chiral molecule adsorption and ordering on a metal surface, and a number of chiral and achiral unit cells have been reported. Herein, we show that given the appropriate annealing treatment, singly deprotonated tartaric acid monolayers can restructure the Cu metal itself, and that the resulting structure is both highly ordered and chiral. Molecular resolution scanning tunneling microscopy reveals that singly deprotonated tartaric acid extracts Cu atoms from the Cu(110) surface layer and incorporates them into highly ordered, chiral adatom arrays capped by a continuous molecular layer. Further evidence for surface restructuring comes from images of atom-deep trenches formed in the Cu(110) surface during the process. These trenches also run in low symmetry directions and are themselves chiral. Simulated scanning tunneling microscopy images are consistent with the appearance of the added atom rows and etched trenches. The chiral imprinting results in a long-range, highly ordered unit cell covering the whole surface as confirmed by low energy electron diffraction. Details of the restructuring mechanism were further investigated via time-lapse imaging at elevated temperature. This work reveals the stages of nanoscale surface restructuring and offers an interesting method for chiral modification of an achiral metal surface.

  19. Long-range RNA pairings contribute to mutually exclusive splicing.

    PubMed

    Yue, Yuan; Yang, Yun; Dai, Lanzhi; Cao, Guozheng; Chen, Ran; Hong, Weiling; Liu, Baoping; Shi, Yang; Meng, Yijun; Shi, Feng; Xiao, Mu; Jin, Yongfeng

    2016-01-01

    Mutually exclusive splicing is an important means of increasing the protein repertoire, by which the Down's syndrome cell adhesion molecule (Dscam) gene potentially generates 38,016 different isoforms in Drosophila melanogaster. However, the regulatory mechanisms remain obscure due to the complexity of the Dscam exon cluster. Here, we reveal a molecular model for the regulation of the mutually exclusive splicing of the serpent pre-mRNA based on competition between upstream and downstream RNA pairings. Such dual RNA pairings confer fine tuning of the inclusion of alternative exons. Moreover, we demonstrate that the splicing outcome of alternative exons is mediated in relative pairing strength-correlated mode. Combined comparative genomics analysis and experimental evidence revealed similar bidirectional structural architectures in exon clusters 4 and 9 of the Dscam gene. Our findings provide a novel mechanistic framework for the regulation of mutually exclusive splicing and may offer potentially applicable insights into long-range RNA-RNA interactions in gene regulatory networks. © 2015 Yue et al.; Published by Cold Spring Harbor Laboratory Press for the RNA Society.

  20. Measured long-range repulsive Casimir–Lifshitz forces

    PubMed Central

    Munday, J. N.; Capasso, Federico; Parsegian, V. Adrian

    2014-01-01

    Quantum fluctuations create intermolecular forces that pervade macroscopic bodies1–3. At molecular separations of a few nanometres or less, these interactions are the familiar van der Waals forces4. However, as recognized in the theories of Casimir, Polder and Lifshitz5–7, at larger distances and between macroscopic condensed media they reveal retardation effects associated with the finite speed of light. Although these long-range forces exist within all matter, only attractive interactions have so far been measured between material bodies8–11. Here we show experimentally that, in accord with theoretical prediction12, the sign of the force can be changed from attractive to repulsive by suitable choice of interacting materials immersed in a fluid. The measured repulsive interaction is found to be weaker than the attractive. However, in both cases the magnitude of the force increases with decreasing surface separation. Repulsive Casimir–Lifshitz forces could allow quantum levitation of objects in a fluid and lead to a new class of switchable nanoscale devices with ultra-low static friction13–15. PMID:19129843

  1. Long-range patterns in Hindmarsh-Rose networks

    NASA Astrophysics Data System (ADS)

    Etémé, Armand Sylvin; Tabi, Conrad Bertrand; Mohamadou, Alidou

    2017-02-01

    Long-range diffusive effects are included in a discrete Hindmarsh-Rose neural network. Their impact on the emergence of nonlinear patterns is investigated via the modulational instability. The whole system is first shown to fully reduce to a single nonlinear differential-difference equation, which has plane wave solutions. The stability of such solutions is investigated and regions of instability are found to be importantly influenced by long-range parameters. The analytical results are confirmed through direct numerical simulations, where scattered and chaotic patterns illustrate the long-range effect. Synchronized states are described by quasi-periodic patterns for nearest-neighbor coupling. The external stimulus is also shown to efficiently control strong long-range effects via more regular spatiotemporal patterns.

  2. Assessment of a long-range corrected hybrid functional

    SciTech Connect

    Vydrov, Oleg A.; Scuseria, Gustavo E.

    2006-12-21

    Common approximate exchange-correlation functionals suffer from self-interaction error, and as a result, their corresponding potentials have incorrect asymptotic behavior. The exact asymptote can be imposed by introducing range separation into the exchange component and replacing the long-range portion of the approximate exchange by the Hartree-Fock counterpart. The authors show that this long-range correction works particularly well in combination with the short-range variant of the Perdew-Burke-Ernzerhof (PBE) exchange functional. This long-range-corrected hybrid, here denoted LC-{omega}PBE, is remarkably accurate for a broad range of molecular properties, such as thermochemistry, barrier heights of chemical reactions, bond lengths, and most notably, description of processes involving long-range charge transfer.

  3. Generation of short and long range temporal correlated noise

    SciTech Connect

    Romero, A.H.; Sancho, J.M.

    1999-11-20

    The authors present the implementation of an algorithm to generate Gaussian random noises with prescribed time correlations that can be either long or short ranged. Examples of Langevin dynamics with short and long range noises are presented and discussed.

  4. Dynamics of Quantum Matter with Long-Range Entanglement

    DTIC Science & Technology

    2013-06-07

    REPORT Final Report: Dynamics of quantum matter with long-range entanglement. 14. ABSTRACT 16. SECURITY CLASSIFICATION OF: Recent experiments on...ultracold atoms in optical lattices have opened a remarkable new window on the dynamics of quantum matter with long-range entanglement. The simplest...paradigm of this is the boson superfluid-insulator quantum phase transition in two spatial dimensions. This project will study the theoretical

  5. Long-range eye tracking: A feasibility study

    SciTech Connect

    Jayaweera, S.K.; Lu, Shin-yee

    1994-08-24

    The design considerations for a long-range Purkinje effects based video tracking system using current technology is presented. Past work, current experiments, and future directions are thoroughly discussed, with an emphasis on digital signal processing techniques and obstacles. It has been determined that while a robust, efficient, long-range, and non-invasive eye tracking system will be difficult to develop, such as a project is indeed feasible.

  6. Long-range surface magnetoplasmons in thin nickel films

    NASA Astrophysics Data System (ADS)

    Hickernell, Robert K.; Sarid, Dror

    1987-08-01

    The results of a theoretical and experimental investigation of long-range surface magnetoplasmons in thin, magnetic metal films are presented. With a transversely applied magnetic field, the reflectance modulation measurements from prism-coupled modes in nickel films are in agreement with the theory. The reflectance modulation is the same order of magnitude for prism-coupled long-range and single-interface magnetoplasmons.

  7. Long-range rapidity correlations in hadron-nucleus interactions

    SciTech Connect

    Capella, A.; Tran Thanh Van, J.

    1984-06-01

    Long-range rapidity correlations between particles produced in proton-nucleus interactions at 200 GeV/c are studied in the multichain dual parton model. A large long-range correlation between particles produced in two rapidity intervals is predicted, provided these two rapidity intervals are properly chosen. The predicted effect is easily measurable. Predictions at 1 TeV are also given.

  8. Long-Range Correlations in Stride Intervals May Emerge from Non-Chaotic Walking Dynamics

    PubMed Central

    Ahn, Jooeun; Hogan, Neville

    2013-01-01

    Stride intervals of normal human walking exhibit long-range temporal correlations. Similar to the fractal-like behaviors observed in brain and heart activity, long-range correlations in walking have commonly been interpreted to result from chaotic dynamics and be a signature of health. Several mathematical models have reproduced this behavior by assuming a dominant role of neural central pattern generators (CPGs) and/or nonlinear biomechanics to evoke chaos. In this study, we show that a simple walking model without a CPG or biomechanics capable of chaos can reproduce long-range correlations. Stride intervals of the model revealed long-range correlations observed in human walking when the model had moderate orbital stability, which enabled the current stride to affect a future stride even after many steps. This provides a clear counterexample to the common hypothesis that a CPG and/or chaotic dynamics is required to explain the long-range correlations in healthy human walking. Instead, our results suggest that the long-range correlation may result from a combination of noise that is ubiquitous in biological systems and orbital stability that is essential in general rhythmic movements. PMID:24086274

  9. Distortion-triggered loss of long-range order in solids with bonding energy hierarchy.

    PubMed

    Kolobov, A V; Krbal, M; Fons, P; Tominaga, J; Uruga, T

    2011-04-01

    An amorphous-to-crystal transition in phase-change materials like Ge-Sb-Te is widely used for data storage. The basic principle is to take advantage of the property contrast between the crystalline and amorphous states to encode information; amorphization is believed to be caused by melting the materials with an intense laser or electrical pulse and subsequently quenching the melt. Here, we demonstrate that distortions in the crystalline phase may trigger a collapse of long-range order, generating the amorphous phase without going through the liquid state. We further show that the principal change in optical properties occurs during the distortion of the still crystalline structure, upsetting yet another commonly held belief that attributes the change in properties to the loss of long-range order. Furthermore, our results suggest a way to lower energy consumption by condensing phase change inducing energy into shorter pulses or through the use of coherent phonon excitation.

  10. Long-range dependence of the two-dimensional Ising model at critical temperature

    NASA Astrophysics Data System (ADS)

    Pipiras, Vladas; Taqqu, Murad S.

    2015-03-01

    The paper gives probabilists who are unfamiliar with the Ising model a coherent, integrated explanation of why the Ising model displays long-range dependence at critical temperature. The Ising model in two dimensions involves spins σj,k = ±1 located at every node (j,k) of the lattice, with nearest neighbor interactions. We shall focus on the covariances [{E}{σ _0},_0{σ _0}{,_N}] and [{E}{σ _0},_0{σ _N}{,_N}] between the spin at the origin and the spin located either on the axis at (0,N) or located on the diagonal at (N,N), when the temperature equals a critical value. Using a recent formulation of the so-called `Szegö's theorem', we explain why these covariances decrease to zero like N-1/4 as N → ∞, thus at a slow enough rate so as to exhibit long-range dependence.

  11. Long-range interactions in lattice field theory

    SciTech Connect

    Rabin, J.M.

    1981-06-01

    Lattice quantum field theories containing fermions can be formulated in a chirally invariant way provided long-range interactions are introduced. It is established that in weak-coupling perturbation theory such a lattice theory is renormalizable when the corresponding continuum theory is, and that the continuum theory is indeed recovered in the perturbative continuum limit. In the strong-coupling limit of these theories one is led to study an effective Hamiltonian describing a Heisenberg antiferromagnet with long-range interactions. Block-spin renormalization group methods are used to find a critical rate of falloff of the interactions, approximately as inverse distance squared, which separates a nearest-neighbor-antiferromagnetic phase from a phase displaying identifiable long-range effects. A duality-type symmetry is present in some block-spin calculations.

  12. Long-range oil and gas forecasting methodologies: literature survey

    SciTech Connect

    Cherniavsky, E.A.

    1980-08-01

    Performance of long-range energy system analyses requires the capability to project conventional domestic oil and gas supplies in the long term. The objective of the Long-range Forecasting Methodology project is to formulate an approach to this problem which will be compatible with the principal tool employed by the Energy Information Administration of the Department of Energy for long-range energy system analyses, the Long-term Energy Analysis Package (LEAP). This paper reports on projection methodologies that have appeared in the literature, evaluates them in terms of their applicability to the LEAP framework, and discusses the principal determinants of conventional domestic oil and gas supply in the long run.

  13. Application of advanced technology to future long-range aircraft

    NASA Technical Reports Server (NTRS)

    Schrader, O. E.

    1976-01-01

    The objective of this paper is to provide an overview assessment of three separate programs at Langley Research Center that have incorporated advanced technology into the design of long-range passenger and cargo aircraft. The first technology centers around the use of an span-loaded cargo aircraft with the payload distributed along the wing. This concept has the potential for reduced structural weights. The second technology is the application of laminar flow control (LFC) to the aircraft to reduce the aerodynamic drag. The use of LFC can reduce the fuel requirements during long-range cruise. The last program evaluates the production of alternate aircraft fuels from coal and the use of liquid hydrogen as an aircraft fuel. Coal-derived hydrogen as an aircraft fuel offers both the prospect for reduced dependence on petroleum fuels and improved performance for long-range aircraft.

  14. Long-range surface plasmons in electrode structures

    NASA Technical Reports Server (NTRS)

    Stegeman, G. I.; Burke, J. J.

    1983-01-01

    Surface polaritons guided by symmetric double metal film structures are analyzed, with particular attention given to the attenuation of the two long-range modes that occur. It is found that long-range surface plasmon polariton modes do exist for double electrode structures over a limited range of material parameters. Guided by thin metal electrodes, surface plasmon polaritons can achieve millimeter plus propagation distances in the near infrared. It is pointed out that if the slab is electrooptic, then very low voltages will be needed to manipulate the waves. The fact that long-range modes exist simultaneously with junction tunnel plasmons may be of use in providing directional radiation from light-emitting junctions or the inverse process of light to electrical energy conversion.

  15. Fourth International Symposium on Long-Range Sound Propagation

    NASA Technical Reports Server (NTRS)

    Willshire, William L., Jr. (Compiler)

    1990-01-01

    Long range sound propagation is an aspect of many acoustical problems ranging from en route aircraft noise to the acoustic detection of aircraft. Over the past decade, the University of Mississippi and the Open University of England, together with a third institution, have held a symposium approx. every 2 years so that experts in the field of long range propagation could exchange information on current research, identify areas needing additional work, and coordinate activities as much as possible. The Fourth International Symposium on Long Range Sound Propagation was jointly sponsored by the University of Mississippi, the Open University of England, and NASA. Papers were given in the following areas: ground effects on propagation; infrasound propagation; and meteorological effects on sound propagation. A compilation of the presentations made at the symposium is presented along with a list of attendees, and the agenda.

  16. Design of a high capacity long range cargo aircraft

    NASA Technical Reports Server (NTRS)

    Weisshaar, Terrence A.

    1994-01-01

    This report examines the design of a long range cargo transport to attempt to reduce ton-mile shipping costs and to stimulate the air cargo market. This design effort involves the usual issues but must also include consideration of: airport terminal facilities; cargo loading and unloading; and defeating the 'square-cube' law to design large structures. This report reviews the long range transport design problem and several solutions developed by senior student design teams at Purdue University. The results show that it will be difficult to build large transports unless the infrastructure is changed and unless the basic form of the airplane changes so that aerodynamic and structural efficiencies are employed.

  17. Small long-range alpha detector (LRAD) with computer readout

    SciTech Connect

    MacArthur, D.W.; Allander, K.S.; Bounds, J.A.; Butterfield, K.B.

    1991-10-01

    The small long-range alpha detector developed by N-2 was described in detail in the Los Alamos publication LA-12073-MS, Long-Range Alpha Detector,'' published in 1991. Since publication of that report, a computerized data acquisition system has been added to the LRAD detector. In addition to detailing the new data acquisition system, we discuss new data generated with the enhanced system, including measurements of (1) ultimate sensitivity; (2) detector linearity; (3) ion lifetime; and (4) characteristics. Furthermore, we have expanded our understanding of ion recombination and statistical noise effects in the LRAD and have addressed them here as well as several proposed applications. 6 refs., 30 figs.

  18. Long-range correction for dipolar fluids at planar interfaces

    NASA Astrophysics Data System (ADS)

    Werth, Stephan; Horsch, Martin; Hasse, Hans

    2015-12-01

    A slab-based long-range correction for dipolar interactions in molecular dynamics simulation of systems with a planar geometry is presented and applied to simulate vapour-liquid interfaces. The present approach is validated with respect to the saturated liquid density and the surface tension of the Stockmayer fluid and a molecular model for ethylene oxide. The simulation results exhibit no dependence on the cut-off radius for radii down to 1 nm, proving that the long-range correction accurately captures the influence of the dipole moment on the intermolecular interaction energies and forces as well as the virial and the surface tension.

  19. Specific heat spectra of long-range correlated DNA molecules

    NASA Astrophysics Data System (ADS)

    Moreira, D. A.; Albuquerque, E. L.; Mauriz, P. W.; Vasconcelos, M. S.

    2006-11-01

    The specific heat spectra of long-range correlated DNA molecules is theoretically analyzed for a stacked array of single-stranded DNA made up from the nucleotides guanine G, adenine A, cytosine C and thymine T arranged in the Fibonacci and Rudin-Shapiro quasiperiodic sequences, with the aim to compare them with those related with a genomic DNA sequence. The energy spectra are calculated using the one-dimensional Schrödinger equation in a tight-binding approximation with the on-site energy exhibiting long-range disorder and nonrandom hopping amplitudes.

  20. Probing the antiferromagnetic long-range order with Glauber spin states

    NASA Technical Reports Server (NTRS)

    Cabrera, Guillermo G.

    1994-01-01

    It is well known that the ground state of low-dimensional antiferromagnets deviates from Neel states due to strong quantum fluctuations. Even in the presence of long-range order, those fluctuations produce a substantial reduction of the magnetic moment from its saturation value. Numerical simulations in anisotropic antiferromagnetic chains suggest that quantum fluctuations over Neel order appear in the form of localized reversal of pairs of neighboring spins. In this paper, we propose a coherent state representation for the ground state to describe the above situation. In the one-dimensional case, our wave function corresponds to a two-mode Glauber state, when the Neel state is used as a reference, while the boson fields are associated to coherent flip of spin pairs. The coherence manifests itself through the antiferromagnetic long-range order that survives the action of quantum fluctuations. The present representation is different from the standard zero-point spin wave state, and is asymptotically exact in the limit of strong anisotropy. The fermionic version of the theory, obtained through the Jordan-Wigner transformation, is also investigated.

  1. Probabilistic approach to long range planning of manpower

    NASA Technical Reports Server (NTRS)

    Lejk, R. A.

    1967-01-01

    Publication presents a total long range planning model for project oriented organizations. The total model consists of planning systems which originate - /1/ at the project level and consolidate into an overall plan, and /2/ from a budetary ceiling and allocate to the individual projects. Analysis of /1/ and /2/ is provided for management decision making.

  2. Air Force B-21 Long Range Strike Bomber

    DTIC Science & Technology

    2016-04-14

    Congressional Research Service 7 Industrial Base Northrop Grumman intends to build the B-21 at its facilities at Air Force Plant 42 in Palmdale, CA, which were...DefenseNews.com, March 2, 2016. 32 A useful discussion of these issues can be found in Andrew Hunter , “Long Range Strike: 3 Lessons from Defense

  3. Strategic Long Range Planning for Universities. AIR Forum 1980 Paper.

    ERIC Educational Resources Information Center

    Baker, Michael E.

    The use of strategic long-range planning at Carnegie-Mellon University (CMU) is discussed. A structure for strategic planning analysis that integrates existing techniques is presented, and examples of planning activities at CMU are included. The key concept in strategic planning is competitive advantage: if a university has a competitive…

  4. Long Range Planning Model. Management for Effective Teaching.

    ERIC Educational Resources Information Center

    Fairfax County Public Schools, VA. Dept. of Instructional Services.

    The Management for Effective Teaching (MET) Long Range Planning Model has been developed to provide practical assistance in planning for classroom management and teaching. The planning procedures were devised to help elementary teachers in the Fairfax County (Virginia) Public Schools implement the school system's Program of Studies. In the model…

  5. Long Range Development Plan, University of California, Riverside.

    ERIC Educational Resources Information Center

    Russell (George Vernon) and Associates, Architects and Planners.

    A long range development plan, conceived as a general guide to final objectives, uses many diagrams and maps to illustrate the text. The plan is predicated on the assumption that orderly and efficient development of site possibilities is subject to ever-changing influences. The following areas are examined--(1) campus environment, (2) academic…

  6. Long-Range Planning--Finances. Higher Education.

    ERIC Educational Resources Information Center

    Ward, Robert C.

    This paper presents views on long-range financial planning for public and private higher education. Emphasis is placed on a mix of revenue sources for future support and on key budgetary considerations such as faculty and non-academic wages, the rising cost of graduate education, and the community and junior college movement. A triple crisis is…

  7. Transport in Nonneutral Plasmas due to Long-Range Collisions

    NASA Astrophysics Data System (ADS)

    Anderegg, F.; Driscoll, C. F.; Hollmann, E. M.; Kriesel, J. M.; Huang, X.-P.; Dubin, D. H. E.; O'Neil, T. M.

    1997-11-01

    Recent experiments on nonneutral plasmas have measured test particle transport, bulk viscous transport, and heat transport; all three measurements show enhanced transport due to long-range interactions. Classical Boltzmann theory describes transport in terms of short-range velocity-scattering collisions with impact parameters less than the cyclotron radius, i.e. ρ < r_c. Here we observe the effects of long-range collisions with rc < ρ applteq λ_D. Experiments show that: a) The measured test particle diffusion across B is about ten times faster than predicted by classical collisional theory, in precise agreement with long-range collisional theory over a wide range of parameters. b) Viscous transport measurements obtained from plasma density profiles relaxing to thermal equilibrium indicate that bulk particle transport across the magnetic field may be enhanced by up to 10^4. c) Preliminary measurements of heat transport created by localized laser cooling or heating indicate that the thermal conductivity can be much larger than predicted by classical theory, consistent with long-range theory. Supported by ONR N00014-96-1-0239 and NSF PHY94-21318. ^**Present address: NIST, 325 Broadway Ave., Boulder CO 80303.

  8. Long Range Development Plan, University of California, Riverside.

    ERIC Educational Resources Information Center

    Russell (George Vernon) and Associates, Architects and Planners.

    A long range development plan, conceived as a general guide to final objectives, uses many diagrams and maps to illustrate the text. The plan is predicated on the assumption that orderly and efficient development of site possibilities is subject to ever-changing influences. The following areas are examined--(1) campus environment, (2) academic…

  9. Long range orbital error estimation for applications satellites

    NASA Technical Reports Server (NTRS)

    Bonavito, N. L.; Foreman, J. C.

    1978-01-01

    A method of optimum orbital averaging was employed to study the long range accuracy potential of polar orbiting applications satellites. This approach involved the determination of the boundary conditions of one set of differential equations of motion by adjusting the initial conditions in a least square sense with the use of data generated by another set of differential equations of motion.

  10. Report of the Board Committee on Long Range Planning.

    ERIC Educational Resources Information Center

    National Association of Educational Broadcasters, Washington, DC.

    The impact of predicted technological developments on educational broadcasting depends on the long range planning done to exploit them. It is expected that in the future computers will be used extensively by broadcasting agencies to collect, analyze, and provide, on call, a wide range of data about audience groupings. Determination of program…

  11. [The Long-Range Plan for Colorado College.

    ERIC Educational Resources Information Center

    Brooks, Glenn

    This is a series of 3 reports to the Colorado College faculty and administration on a long-range plan. The first report deals with some of the technical features of a modular course plan, mainly: (1) the construction of a modular schedule, (2) registration and enrollment procedures, and (3) campus space and fixtures. The second report contains a…

  12. Strategic Long Range Planning for Universities. AIR Forum 1980 Paper.

    ERIC Educational Resources Information Center

    Baker, Michael E.

    The use of strategic long-range planning at Carnegie-Mellon University (CMU) is discussed. A structure for strategic planning analysis that integrates existing techniques is presented, and examples of planning activities at CMU are included. The key concept in strategic planning is competitive advantage: if a university has a competitive…

  13. SOVIET LONG-RANGE SPACE-EXPLORATION PROGRAM: ANALYTICAL SURVEY

    DTIC Science & Technology

    This analytical survey is based on Soviet open sources published 1956-1965. It is one of a series of reports dealing with the Soviet long-range space ... exploration program and is concerned, in particular, with lunar surface research. Information not directly related to this subject has been included

  14. Long-Range Epistasis Mediated by Structural Change in a Model of Ligand Binding Proteins.

    PubMed

    Nelson, Erik D; Grishin, Nick V

    2016-01-01

    Recent analyses of amino acid mutations in proteins reveal that mutations at many pairs of sites are epistatic-i.e., their effects on fitness are non-additive-the combined effect of two mutations being significantly larger or smaller than the sum of their effects considered independently. Interestingly, epistatic sites are not necessarily near each other in the folded structure of a protein, and may even be located on opposite sides of a molecule. However, the mechanistic reasons for long-range epistasis remain obscure. Here, we study long-range epistasis in proteins using a previously developed model in which off-lattice polymers are evolved under ligand binding constraints. Epistatic effects in the model are qualitatively similar to those recently reported for small proteins, and many are long-range. We find that a major reason for long-range epistasis is conformational change-a recurrent theme in both positive and negative epistasis being the transfer, or exchange of material between the ordered nucleus, which supports the binding site, and the liquid-like surface of a folded molecule. These local transitions in phase and folded structure are largely responsible for long-range epistasis in our model.

  15. Live four-dimensional optical coherence tomography reveals embryonic cardiac phenotype in mouse mutant

    NASA Astrophysics Data System (ADS)

    Lopez, Andrew L., III; Wang, Shang; Larin, Kirill V.; Overbeek, Paul A.; Larina, Irina V.

    2015-09-01

    Efficient phenotyping of developmental defects in model organisms is critical for understanding the genetic specification of normal development and congenital abnormalities in humans. We previously reported that optical coherence tomography (OCT) combined with live embryo culture is a valuable tool for mouse embryo imaging and four-dimensional (4-D) cardiodynamic analysis; however, its capability for analysis of mouse mutants with cardiac phenotypes has not been previously explored. Here, we report 4-D (three-dimensional+time) OCT imaging and analysis of the embryonic heart in a Wdr19 mouse mutant, revealing a heart looping defect. Quantitative analysis of cardiac looping revealed a statistically significant difference between mutant and control embryos. Our results indicate that live 4-D OCT imaging provides a powerful phenotyping approach to characterize embryonic cardiac function in mouse models.

  16. Probing the role of long-range interactions in the dynamics of a long-range Kitaev chain

    NASA Astrophysics Data System (ADS)

    Dutta, Anirban; Dutta, Amit

    2017-09-01

    We study the role of long-range interactions (more precisely, the long-range superconducting gap term) on the nonequilibrium dynamics considering a long-range p -wave superconducting chain in which the superconducting term decays with distance between two sites in a power-law fashion characterized by an exponent α . We show that the Kibble-Zurek scaling exponent, dictating the power-law decay of the defect density in the final state reached following a slow (in comparison to the time scale associated with the minimum gap in the spectrum of the Hamiltonian) quenching of the chemical potential μ across a quantum critical point, depends nontrivially on the exponent α as long as α <2 ; on the other hand, for α >2 , we find that the exponent saturates to the corresponding well-known value of 1 /2 expected for the short-range model. Furthermore, studying the dynamical quantum phase transitions manifested in the nonanalyticities in the rate function of the return possibility I (t ) in subsequent temporal evolution following a sudden change in μ , we show the existence of a new region; in this region, we find three instants of cusp singularities in I (t ) associated with a single sector of Fisher zeros. Notably, the width of this region shrinks as α increases and vanishes in the limit α →2 , indicating that this special region is an artifact of the long-range nature of the Hamiltonian.

  17. Coherent heat patterns revealed by unsupervised classification of Argo temperature profiles in the North Atlantic Ocean

    NASA Astrophysics Data System (ADS)

    Maze, Guillaume; Mercier, Herlé; Fablet, Ronan; Tandeo, Pierre; Lopez Radcenco, Manuel; Lenca, Philippe; Feucher, Charlène; Le Goff, Clément

    2017-02-01

    A quantitative understanding of the integrated ocean heat content depends on our ability to determine how heat is distributed in the ocean and identify the associated coherent patterns. This study demonstrates how this can be achieved using unsupervised classification of Argo temperature profiles. The classification method used is a Gaussian Mixture Model (GMM) that decomposes the Probability Density Function of a dataset into a weighted sum of Gaussian modes. It is determined that the North Atlantic Argo dataset of temperature profiles contains 8 groups of vertically coherent heat patterns, or classes. Each of the temperature profile classes reveals unique and physically coherent heat distributions along the vertical axis. A key result of this study is that, when mapped in space, each of the 8 classes is found to define an oceanic region, even if no spatial information was used in the model determination. The classification result is independent of the location and time of the ARGO profiles. Two classes show cold anomalies throughout the water column with amplitude decreasing with depth. They are found to be localized in the subpolar gyre and along the poleward flank of the Gulf Stream and North Atlantic Current (NAC). One class has nearly zero anomalies and a large spread throughout the water column. It is found mostly along the NAC. One class has warm anomalies near the surface (50 m) and cold ones below 200 m. It is found in the tropical/equatorial region. The remaining four classes have warm anomalies throughout the water column, one without depth dependance (in the southeastern part of the subtropical gyre), the other three with clear maximums at different depths (100 m, 400 m and 1000 m). These are found along the southern flank of the North Equatorial Current, the western part of the subtropical gyre and over the West European Basin. These results are robust to both the seasonal variability and to method parameters such as the size of the analyzed domain.

  18. Long-range intermolecular interaction between broken DNA fragments

    NASA Astrophysics Data System (ADS)

    Pinchuk, Anatoliy O.; Vysotskii, Vladimir I.

    2001-03-01

    We analyzed the long-range intermolecular interaction between fragments of broken DNA. We considered two constituents of long-range intermolecular interaction. The first is a net electrostatic Coulomb interaction between charges, involved in a structure of opposite nucleotides, which we evaluate using Debye-Huckel theory. The second one is the Van der Waals interaction between the nucleotides. The general Lifshitz theory of Van der Waals forces was used to evaluate this interaction. Numerical calculations showed that a repulsive force between broken DNA fragments can arise in specific cases. This repulsion can prevent DNA from repairing itself after a double-strand break. The height of the barrier decreases with an increase of the ionic strength of the intracellular milieu, or with a reduction of its viscosity.

  19. Temperature inversion in long-range interacting systems.

    PubMed

    Teles, Tarcísio N; Gupta, Shamik; Di Cintio, Pierfrancesco; Casetti, Lapo

    2015-08-01

    Temperature inversions occur in nature, e.g., in the solar corona and in interstellar molecular clouds: Somewhat counterintuitively, denser parts of the system are colder than dilute ones. We propose a simple and appealing way to spontaneously generate temperature inversions in systems with long-range interactions, by preparing them in inhomogeneous thermal equilibrium states and then applying an impulsive perturbation. In similar situations, short-range systems would typically relax to another thermal equilibrium, with a uniform temperature profile. By contrast, in long-range systems, the interplay between wave-particle interaction and spatial inhomogeneity drives the system to nonequilibrium stationary states that generically exhibit temperature inversion. We demonstrate this mechanism in a simple mean-field model and in a two-dimensional self-gravitating system. Our work underlines the crucial role the range of interparticle interaction plays in determining the nature of steady states out of thermal equilibrium.

  20. Optical measurements of long-range protein vibrations.

    PubMed

    Acbas, Gheorghe; Niessen, Katherine A; Snell, Edward H; Markelz, A G

    2014-01-01

    Protein biological function depends on structural flexibility and change. From cellular communication through membrane ion channels to oxygen uptake and delivery by haemoglobin, structural changes are critical. It has been suggested that vibrations that extend through the protein play a crucial role in controlling these structural changes. While nature may utilize such long-range vibrations for optimization of biological processes, bench-top characterization of these extended structural motions for engineered biochemistry has been elusive. Here we show the first optical observation of long-range protein vibrational modes. This is achieved by orientation-sensitive terahertz near-field microscopy measurements of chicken egg white lysozyme single crystals. Underdamped modes are found to exist for frequencies >10 cm(-1). The existence of these persisting motions indicates that damping and intermode coupling are weaker than previously assumed. The methodology developed permits protein engineering based on dynamical network optimization.

  1. Optical measurements of long-range protein vibrations

    NASA Astrophysics Data System (ADS)

    Acbas, Gheorghe; Niessen, Katherine A.; Snell, Edward H.; Markelz, A. G.

    2014-01-01

    Protein biological function depends on structural flexibility and change. From cellular communication through membrane ion channels to oxygen uptake and delivery by haemoglobin, structural changes are critical. It has been suggested that vibrations that extend through the protein play a crucial role in controlling these structural changes. While nature may utilize such long-range vibrations for optimization of biological processes, bench-top characterization of these extended structural motions for engineered biochemistry has been elusive. Here we show the first optical observation of long-range protein vibrational modes. This is achieved by orientation-sensitive terahertz near-field microscopy measurements of chicken egg white lysozyme single crystals. Underdamped modes are found to exist for frequencies >10 cm-1. The existence of these persisting motions indicates that damping and intermode coupling are weaker than previously assumed. The methodology developed permits protein engineering based on dynamical network optimization.

  2. Entanglement Area Laws for Long-Range Interacting Systems

    NASA Astrophysics Data System (ADS)

    Gong, Zhe-Xuan; Foss-Feig, Michael; Brandão, Fernando G. S. L.; Gorshkov, Alexey V.

    2017-08-01

    We prove that the entanglement entropy of any state evolved under an arbitrary 1 /rα long-range-interacting D -dimensional lattice spin Hamiltonian cannot change faster than a rate proportional to the boundary area for any α >D +1 . We also prove that for any α >2 D +2 , the ground state of such a Hamiltonian satisfies the entanglement area law if it can be transformed along a gapped adiabatic path into a ground state known to satisfy the area law. These results significantly generalize their existing counterparts for short-range interacting systems, and are useful for identifying dynamical phase transitions and quantum phase transitions in the presence of long-range interactions.

  3. Long-range correlations in chaotic cellular automata

    NASA Astrophysics Data System (ADS)

    Eisele, Michael

    1991-03-01

    One-dimensional cellular automata of class 3 are studied as models for spatially extended, chaotic systems. Their irreversible dynamics can generate weak, but long-range spatial correlations. The one labelled 22 by Wolfram is treated in an exemplary way. Its stationary state is approximated by a Markov chain. The regular grammar underlying the Markov chain is chosen with care, so that it includes a maximum amount of information on the stationary state. The approximation can be performed without simulating the dynamics of the cellular automaton 22 and reproduces its long-range correlations qualitatively. Their origin is explained intuitively and they are argued to be a frequent feature of cellular automata with more complicated rules.

  4. Long-range correlation analysis of urban traffic data

    NASA Astrophysics Data System (ADS)

    Sheng, Peng; Wang, Jun-Feng; Tang, Tie-Qiao; Zhao, Shu-Long

    2010-08-01

    This paper investigates urban traffic data by analysing the long-range correlation with detrended fluctuation analysis. Through a large number of real data collected by the travel time detection system in Beijing, the variation of flow in different time periods and intersections is studied. According to the long-range correlation in different time scales, it mainly discusses the effect of intersection location in road net, people activity customs and special traffic controls on urban traffic flow. As demonstrated by the obtained results, the urban traffic flow represents three-phase characters similar to highway traffic. Moreover, compared by the two groups of data obtained before and after the special traffic restrictions (vehicles with special numbered plates only run in a special workday) enforcement, it indicates that the rules not only reduce the flow but also avoid irregular fluctuation.

  5. The design of a long-range megatransport aircraft

    NASA Technical Reports Server (NTRS)

    Weisshaar, Terrence A.; Allen, Carl L.

    1992-01-01

    Aircraft manufacturers are examining the market and feasibility of long-range passenger aircraft carrying more than 600 passengers. These aircraft would carry travelers at reduced cost and, at the same time, reduce congestion around major airports. The design of a large, long-range transport involves broad issues such as: the integration of airport terminal facilities; passenger loading and unloading; trade-offs between aircraft size and the cost to reconfigure these existing facilities; and, defeating the 'square-cube' law. Thirteen Purdue design teams generated RFP's that defined passenger capability and range, based upon team perception of market needs and infrastructure constraints. Turbofan engines were designed by each group to power these aircraft. The design problem and the variety of solutions developed are reviewed.

  6. The Dependence of Long-Range Reverberation on Bottom Roughness

    NASA Astrophysics Data System (ADS)

    Gauss, Roger; Fromm, David; LePage, Kevin; Gragg, Robert

    2004-11-01

    At long-range, shallow-water reverberation can be driven by sub-critical-angle scattering, i.e. by rough interrace scattering. The Naval Research Laboratory has recently developed a small-slope model for elastic seafloors that provides physics-based estimates of the dependence of scattering on the incident and scattered angles, and physical descriptors of the environment. In this paper, this incoherent model is used as kernels in reverberation models, which in turn are used to assess the sensitivity at 3.5 kHz of long-range monostatic reverberation to the roughness of the water-sediment interface. It is shown that when sub-critical-angle scattering dominates, the acoustic field could be quite sensitive to the parameter values of the roughness, thus arguing for the need for regional in-situ methods for its estimation.

  7. Travel: a long-range goal of retired women.

    PubMed

    Staats, Sara; Pierfelice, Loretta

    2003-09-01

    The authors surveyed retired persons (predominately women) with regard to their immediate, intermediate, and long-range activities following retirement. As predicted, leisure travel emerged as a frequent long-range goal for persons retired more than 5 years. The travel activity preferences of long-retired older women present challenges and opportunities to both researchers and marketers. Length of trips and frequency of trips have been predicted from regression models, with trip length in particular being well predicted by the problem of daily life hassles. A theoretical model of continued post-retirement travel is presented as a variant of Solomon's opponent process theory of affect (R. L. Solomon, 1980). The authors suggest that to the degree that places traveled to are varied and different, older people may remain stimulated and continue to enjoy retirement.

  8. Reaching for the Horizon: The 2015 NSAC Long Range Plan

    NASA Astrophysics Data System (ADS)

    Geesaman, Donald

    2015-10-01

    In April 2014, the Nuclear Science Advisory Committee was charged to conduct a new study of the opportunities and priorities for United States nuclear physics research and to recommend a long range plan for the coordinated advancement of the Nation's nuclear science program over the next decade. The entire community actively contributed to developing this plan. Ideas and goals, new and old, were examined and community priorities were established. The Long Range Plan Working Group gathered at Kitty Hawk, NC to converge on the recommendations. In this talk I will discuss the vision for the future that has emerged from this process. The new plan, ``Reaching for the Horizon,'' offers the promise of great leaps forward in our understanding of nuclear science and new opportunities for nuclear science to serve society. This work was supported by the U. S. Department of Energy, Office of Science, Office of Nuclear Physics, under Contract No. DE-AC02-06CH11357.

  9. Long-range mutual information and topological uncertainty principle

    NASA Astrophysics Data System (ADS)

    Jian, Chao-Ming; Kim, Isaac; Qi, Xiao-Liang

    Ordered phases in Landau paradigm can be diagnosed by a local order parameter, whereas topologically ordered phases cannot be detected in such a way. In this paper, we propose long-range mutual information (LRMI) as a unified diagnostic for both conventional long-range order and topological order. Using the LRMI, we characterize orders in n +1D gapped systems as m-membrane condensates with 0 <= m <= n-1. The familiar conventional order and 2 +1D topological orders are respectively identified as 0-membrane and 1-membrane condensates. We propose and study the topological uncertainty principle, which describes the non-commuting nature of non-local order parameters in topological orders.

  10. Long-range exciton dissociation in organic solar cells.

    PubMed

    Caruso, Domenico; Troisi, Alessandro

    2012-08-21

    It is normally assumed that electrons and holes in organic solar cells are generated by the dissociation of excitons at the interface between donor and acceptor materials in strongly bound hole-electron pairs. We show in this contribution that excitons can dissociate tens of angstroms away from the interface and generate partially separated electrons and holes, which can more easily overcome their coulombic attraction and form free charges. We first establish under what conditions long-range exciton dissociation is likely (using a kinetic model and a microscopic model for the calculation of the long-range electron transfer rate). Then, defining a rather general model Hamiltonian for the donor material, we show that the phenomenon is extremely common in the majority of polymer:fullerene bulk heterojunction solar cells.

  11. Long range science scheduling for the Hubble Space Telescope

    NASA Technical Reports Server (NTRS)

    Miller, Glenn; Johnston, Mark

    1991-01-01

    Observations with NASA's Hubble Space Telescope (HST) are scheduled with the assistance of a long-range scheduling system (SPIKE) that was developed using artificial intelligence techniques. In earlier papers, the system architecture and the constraint representation and propagation mechanisms were described. The development of high-level automated scheduling tools, including tools based on constraint satisfaction techniques and neural networks is described. The performance of these tools in scheduling HST observations is discussed.

  12. The design of a long range megatransport aircraft

    NASA Technical Reports Server (NTRS)

    Weisshaar, Terrence A.; Allen, Carl L.

    1992-01-01

    During the period from August 1991 - June 1992 two design classes at Purdue University participated in the design of a long range, high capacity transport aircraft, dubbed the megatransport. Thirteen Purdue design teams generated RFP's that defined passenger capability and range, based upon team perception of market needs and infrastructure constraints. Turbofan engines were designed by each group to power these aircraft. The design problem and the variety of solutions developed are described in an attached paper.

  13. Dissipative long-range entanglement generation between electronic spins

    NASA Astrophysics Data System (ADS)

    Benito, M.; Schuetz, M. J. A.; Cirac, J. I.; Platero, G.; Giedke, G.

    2016-09-01

    We propose a scheme for deterministic generation and long-term stabilization of entanglement between two electronic spin qubits confined in spatially separated quantum dots. Our approach relies on an electronic quantum bus, consisting either of quantum Hall edge channels or surface acoustic waves, that can mediate long-range coupling between localized spins over distances of tens of micrometers. Since the entanglement is actively stabilized by dissipative dynamics, our scheme is inherently robust against noise and imperfections.

  14. Long Range Interactions With Laser Cooled Neutral Atoms

    SciTech Connect

    Gattobigio, Giovanni Luca; Michaud, Franck; Labeyrie, Guillaume; Kaiser, Robin; Loureiro, Jorge; Mendonca, Jose Tito; Tercas, Hugo; Pohl, Thomas

    2008-09-07

    Multiple scattering of light in a trap of laser cooled neutral atoms leads to repulsion forces between the atoms. The corresponding interactions have long range behavior in 1/r{sup 2} and are thus similar to Coulomb interaction in an one component confined plasma. Consequences of these interactions will be described in this paper, including the limitation of the spatial density one can obtain in such systems and self-sustained oscillations of the cloud.

  15. Extreme long range process effects characterization and compensation

    NASA Astrophysics Data System (ADS)

    Figueiro, Thiago; Browning, Clyde; Thornton, Martin J.; Vannuffel, Cyril; Choi, Kang-Hoon; Hohle, Christoph; Tortai, Jean-Herve; Schiavone, Patrick

    2013-10-01

    Proximity Effects in electron beam lithography impact feature dimensions, pattern fidelity and uniformity. These effects are addressed using a mathematical model representing the radial exposure intensity distribution induced by a point electron source, commonly named as the Point Spread Function (PSF). PSF models are usually employed for predicting and compensating for effects up to 15μm. It is well known that there are also some process related phenomena that impact pattern uniformity that have a longer range, namely CMP effects, fogging, etc. Performing proximity effects corrections can result in lengthy run times as file size and pattern densities continue to increase exponentially per technology node. Running corrections for extreme long range phenomena becomes computational and file size prohibitive. Nevertheless, since extreme long range may reach up several millimeters, and new technology nodes require a high level of precision, a strategy for predicting and compensating these phenomena is crucial. In this paper a set of test patterns are presented in order to verify and calibrate the so called extreme long range effects in the electron beam lithography. Moreover, a strategy to compensate for extreme long range effects based on the pattern density is presented. Since the evaluation is based on a density map instead of the actual patterns, the computational effort is feasible. The proposed method may be performed off-line (in contrast to machine standard in-line correction). The advantage of employing off-line compensation relies on enhancing the employ of dose and/or geometry modulation. This strategy also has the advantage of being completely decoupled from other e-beam writer's internal corrections (like Fogging Effect Correction - FEC).

  16. Long range Ising model for credit risk modeling

    NASA Astrophysics Data System (ADS)

    Molins, Jordi; Vives, Eduard

    2005-07-01

    Within the framework of maximum entropy principle we show that the finite-size long-range Ising model is the adequate model for the description of homogeneous credit portfolios and the computation of credit risk when default correlations between the borrowers are included. The exact analysis of the model suggest that when the correlation increases a first-order-like transition may occur inducing a sudden risk increase.

  17. IMI long-range surface plasmon Bragg micro-cavity

    NASA Astrophysics Data System (ADS)

    Tong, Kai; Wang, Jun; Zhou, Chunliang; Wang, Meiting

    2016-10-01

    The defect layer is introduced to the insulator-metal-insulator (IMI) Bragg waveguide structure. The micro-cavity structure of long-range surface plasma is proposed based on the defect mode. The liquid crystal is the defect layer in the structure of Bragg. The energy band characteristics of the long-range surface plasmon Bragg micro-cavity structure are analyzed by using the finite difference time domain method. The influence of the period number and the length of the micro-cavity on the quality factor Q and the volume V of the Bragg grating are discussed. The results show that the photonic energy can be confined very well in the micro-cavity by the structure of the micro-cavity. By controlling the birefringence of liquid crystal, the resonance wavelength of the micro-cavity appears with redshift phenomenon. The tuning range is 42 nm. The tuning of the working window of the long-range surface plasmon filter is realized. The photonic energy is the strongest in the insulating layer and the metal interface. The increase of cycles number has certain limitation on the improvement of the quality factor Q of the cavity. The influence of the defect-cavity length on the resonant wavelength, the quality factor Q and the mode volume V is obvious. The performance of the micro-cavity can be improved by adjusting the number of the micro-cavity and the length of the defect-cavity, and the ratio of Q/V can reach 43,750 in the communication band. The nano micro-cavity provides a new design idea and basis for the fabrication of tunable long-range surface plasmon wave filter in this paper.

  18. Emergent long-range couplings in arrays of fluid cells

    SciTech Connect

    Abraham, Douglas Bruce

    2014-08-07

    We present a system exhibiting extraordinarily long-range cooperative effects, on a length scale far exceeding the bulk correlation length. We give a theoretical explanation of these phenomena based on the mesoscopic picture of phase coexistence in finite systems, which is confirmedly Monte Carlo (MC) simulation studies. Our work demonstrates that such action-at-a-distance can occur in classical systems involving simple or complex fluids, such as colloid-polymer mixtures, or ferromagnets.

  19. Acceleration of Evolutionary Spread by Long-Range Dispersal

    NASA Astrophysics Data System (ADS)

    Hallatschek, Oskar

    2014-03-01

    The spreading of evolutionary novelties across populations is the central element of adaptation. Unless population are well-mixed (like bacteria in a shaken test tube), the spreading dynamics not only depends on fitness differences but also on the dispersal behavior of the species. Spreading at a constant speed is generally predicted when dispersal is sufficiently short-ranged. However, the case of long-range dispersal is unresolved: While it is clear that even rare long-range jumps can lead to a drastic speedup, it has been difficult to analyze the ensuing stochastic growth process. We present a simple self-consistent argument supported by simulations that accurately predicts evolutionary spread for broad distributions of long distance dispersal. In contrast to the exponential laws predicted by deterministic ``mean-field'' models, spread is either according to a super-linear power-law or a stretched exponential law, depending on the tails of the dispersal kernel. Fluctuations and the relation to supercritical long-range percolation are discussed. Due to the simplicity of our model, which lacks any complex interactions between individuals, we expect our results to be applicable to a wide range of spreading processes. Our results may be used, in particular, to estimate the spread of modern human epidemics, which are greatly accelerated by the human aviation. Based on joint work with Daniel S. Fisher, Stanford.

  20. Long-range infrasound monitoring of eruptive volcanoes.

    NASA Astrophysics Data System (ADS)

    Marchetti, Emanuele; Innocenti, Lorenzo; Ulivieri, Giacomo; Lacanna, Giorgio; Ripepe, Maurizio

    2016-04-01

    The efficient long-range propagation in the atmosphere makes infrasound of active volcanoes extremely promising and opens new perspectives for volcano monitoring at large scale. In favourable propagation conditions, long-range infrasound observations can be used to track the occurrence and the duration of volcanic eruptions also at remote non-monitored volcanoes, but its potential to infer volcanic eruptive source term is still debated. We present results of comparing five years of infrasound of eruptive activity at Mt.Etna volcano (Italy) recorded both at local (~5 km) and at regional distances (~600 km) from the source. Infrasound of lava fountains at Etna volcano, occurring in between 2010 and 2015, are analysed in terms of the local and regional wavefield record, and by comparing to all available volcanic source terms (i.e. plume height and mass eruption rates). Besides, the potential of near real-time notification of ongoing volcanic activity at Etna volcano at a regional scale is investigated. In particular we show how long range infrasound, in the case of Etna volcano, can be used to promptly deliver eruption notification and reliability is constrained by the results of the local array. This work is performed in the framework of the H2020 ARISE2 project funded by the EU in the period 2015-2018.

  1. Long-range scaling behaviours of human colonic pressure activities

    NASA Astrophysics Data System (ADS)

    Yan, Rongguo; Yan, Guozheng; Zhang, Wenqiang; Wang, Long

    2008-11-01

    The long-range scaling behaviours of human colonic pressure activities under normal physiological conditions are studied by using the method of detrended fluctuation analysis (DFA). The DFA is an effective period representation with a single quantitative scaling exponent α to accurately quantify long-range correlations naturally presented in a complex non-stationary time series. The method shows that the colonic activities of the healthy subjects exhibit long-range power-law correlations; however such correlations either will be destroyed if we randomly shuffle the original data or will cease to be of a power-law form if we chop some high-amplitude spikes off. These facts indicate that the colonic tissue or enteric nervous system (ENS) with a good functional motility has a good memory to its past behaviours and generates well-organized colonic spikes; however such good memory becomes too long to be remembered for the colonic activity of the slow transit constipation (STC) patient and colonic dysmotility occurs.

  2. Continuous concentric lamellar block copolymer nanofibers with long range order.

    PubMed

    Ma, Minglin; Titievsky, Kirill; Thomas, Edwin L; Rutledge, Gregory C

    2009-04-01

    Fibers with long-range ordered internal structures have applications in various areas such as photonic band gap fibers, optical waveguides, wearable power, sensors, and sustained drug release. Up to now, such fibers have been formed by melt extrusion or drawing from a macroscopic preformed rod and were typically limited to diameters >10 microm with internal features >1 microm (Abouraddy, A. F.; et al. Nat. Mater. 2007, 6, 336). We describe a new class of continuous fibers and fibrous membranes with long-range ordered concentric lamellar structure that have fiber diameters and feature sizes 2-3 orders of magnitude smaller than those made by conventional methods. These fibers are created through confined self-assembly of block copolymers within core-shell electrospun filaments. In contrast to the copolymer in bulk or thin films, the domains of the concentric lamellar structure are shown here to vary quantitatively with (radial) position and to exhibit a novel dislocation that accommodates variations in fiber diameter robustly, permitting for the first time the realization of long-range order in technologically meaningful, continuous fibers with approximately 300 nm diameter and 50 nm radial period.

  3. Possible Long Range Component in the Nuclear Force

    NASA Astrophysics Data System (ADS)

    Sawada, T.

    In search of the possible long range force between hadrons, S wave phase shift data of the proton-proton scattering are analyzed. In the analysis, the once subtracted Kantor amplitude is calculated, and the one-pion exchange contribution is separated. The remainder of the Kantor amplitude has a huge cusp at the threshold with the attractive sign. It is shown that such a cusp cannot be fitted by the spectral function of the twopion exchange, since it starts at t = 4μ {π }2 . The cusp is fitted by a potential of the long range type with the asymptotic form of V(r) -C/rα. After the chi square search, it turns out α is 6.1 7 and C is positive and has the strength of the strong interaction. It is consistent with the potential of the strong van der Waals force. The transition from the London type to the Casimir-Polder type of the van der Waals interaction is examined. Possible experiments to observe directly such a long range force in the nuclear force are also indicated.

  4. Long-range electrostatic screening in ionic liquids.

    PubMed

    Gebbie, Matthew A; Dobbs, Howard A; Valtiner, Markus; Israelachvili, Jacob N

    2015-06-16

    Electrolyte solutions with high concentrations of ions are prevalent in biological systems and energy storage technologies. Nevertheless, the high interaction free energy and long-range nature of electrostatic interactions makes the development of a general conceptual picture of concentrated electrolytes a significant challenge. In this work, we study ionic liquids, single-component liquids composed solely of ions, in an attempt to provide a novel perspective on electrostatic screening in very high concentration (nonideal) electrolytes. We use temperature-dependent surface force measurements to demonstrate that the long-range, exponentially decaying diffuse double-layer forces observed across ionic liquids exhibit a pronounced temperature dependence: Increasing the temperature decreases the measured exponential (Debye) decay length, implying an increase in the thermally driven effective free-ion concentration in the bulk ionic liquids. We use our quantitative results to propose a general model of long-range electrostatic screening in ionic liquids, where thermally activated charge fluctuations, either free ions or correlated domains (quasiparticles), take on the role of ions in traditional dilute electrolyte solutions. This picture represents a crucial step toward resolving several inconsistencies surrounding electrostatic screening and charge transport in ionic liquids that have impeded progress within the interdisciplinary ionic liquids community. More broadly, our work provides a previously unidentified way of envisioning highly concentrated electrolytes, with implications for diverse areas of inquiry, ranging from designing electrochemical devices to rationalizing electrostatic interactions in biological systems.

  5. Characterization of long-range transport of aerosols over Austria

    NASA Astrophysics Data System (ADS)

    Talianu, Camelia; Seibert, Petra

    2017-04-01

    The long-range transport of aerosols over Austria is characterized using measurements from EARLINET lidar stations and AERONET stations closest to Austria, and aerosol transport models. The analysis is based on selected events of long-range transport of aerosols recorded over Central and South-Eastern Europe: dust, biomass burning, continental aerosols and a special case of volcanic ash, using measurements from EARLINET and AERONET stations around Austria: Garmisch-Partenkirchen, Munich, Leipzig (all stations located in Germany), and Bucharest (Romania). Aerosol layers have been determined using a wavelet analysis applied to the lidar measurements. The optical properties of these aerosols have been also determined from lidar and sunphotometer measurements. The analysis of the trajectories has been performed with the FLEXTRA model, while the estimation of the potential areas of aerosols' sources has been performed using FLEXPART transport model. Based on the spatial and temporal distributions of the trajectories, the main groups of trajectories have been identified using a cluster analysis. The results shows that the long-range transported aerosols over Austria in the spring and summer seasons originate mainly from Sahara (dust) and Canada (biomass burning), coming over Germany. A comparison of the results with the CALIPSO satellite measurements over Austria is also performed. Supported by Austrian Science Fund FWF, Project M 2031, Meitner-Programm.

  6. Long range interactions on wires: A reciprocal space based formalism

    NASA Astrophysics Data System (ADS)

    Mináry, Peter; Morrone, Joseph A.; Yarne, Dawn A.; Tuckerman, Mark E.; Martyna, Glenn J.

    2004-12-01

    There are many atomic scale systems in materials, chemistry, and biology that can be effectively modeled as finite in two of the physical spatial dimensions and periodically replicated in the third including nanoscale metallic and semiconducting wires, carbon nanotubes, and DNA. However, it is difficult to design techniques to treat long range forces in these systems without truncation or recourse to slowly convergent supercells or computationally inefficient Poisson solvers. In this paper, a rigorous reciprocal space based formalism which permits long range forces on wires to be evaluated simply and easily via a small modification of existing methods for three dimensional periodicity is derived. The formalism is applied to determine long range interactions both between point particles using an Ewald-like approach and the continuous charge distributions that appear in electronic structure calculations. In this way, both empirical force field calculations and, for example, plane-wave based density functional theory computations on wires can be performed easily. The methodology is tested on model and realistic systems including a lithium doped carbon nanotube.

  7. Long-range electrostatic screening in ionic liquids

    PubMed Central

    Gebbie, Matthew A.; Dobbs, Howard A.; Valtiner, Markus; Israelachvili, Jacob N.

    2015-01-01

    Electrolyte solutions with high concentrations of ions are prevalent in biological systems and energy storage technologies. Nevertheless, the high interaction free energy and long-range nature of electrostatic interactions makes the development of a general conceptual picture of concentrated electrolytes a significant challenge. In this work, we study ionic liquids, single-component liquids composed solely of ions, in an attempt to provide a novel perspective on electrostatic screening in very high concentration (nonideal) electrolytes. We use temperature-dependent surface force measurements to demonstrate that the long-range, exponentially decaying diffuse double-layer forces observed across ionic liquids exhibit a pronounced temperature dependence: Increasing the temperature decreases the measured exponential (Debye) decay length, implying an increase in the thermally driven effective free-ion concentration in the bulk ionic liquids. We use our quantitative results to propose a general model of long-range electrostatic screening in ionic liquids, where thermally activated charge fluctuations, either free ions or correlated domains (quasiparticles), take on the role of ions in traditional dilute electrolyte solutions. This picture represents a crucial step toward resolving several inconsistencies surrounding electrostatic screening and charge transport in ionic liquids that have impeded progress within the interdisciplinary ionic liquids community. More broadly, our work provides a previously unidentified way of envisioning highly concentrated electrolytes, with implications for diverse areas of inquiry, ranging from designing electrochemical devices to rationalizing electrostatic interactions in biological systems. PMID:26040001

  8. Off-Diagonal Long-Range Order, Restricted Gauge Transformations, and Aharonov-Bohm Effect in Conductors

    SciTech Connect

    Peshkin, Murray

    1996-03-25

    The electrons in a conductor surrounding an external magnetic field are acted on by a vector potential that cannot be removed by a gauge transformation. Nevertheless, a macroscopic normal conductor can experience no Aharonov-Bohm (AB) effect. That is proved by assuming only that a normal conductor lacks off-diagonal long-range order (ODLRO), which means that the electrons lack long-range phase coherence. Then by restricting the Hilbert space to density matrices which lack ODLRO, one can introduce a restricted gauge transformation that removes the interaction of the conductor with the vector potential. Consequently, the AB effect on a beam particle is not shielded by the conductor.

  9. Off-Diagonal Long-Range Order, Restricted Gauge Transformations, and Aharonov-Bohm Effect in Conductors

    NASA Astrophysics Data System (ADS)

    Peshkin, Murray

    1996-03-01

    The electrons in a conductor surrounding an external magnetic field are acted on by a vector potential that cannot be removed by a gauge transformation. Nevertheless, a macroscopic normal conductor can experience no Aharonov-Bohm (AB) effect. That is proved by assuming only that a normal conductor lacks off-diagonal long-range order (ODLRO), which means that the electrons lack long-range phase coherence. Then by restricting the Hilbert space to density matrices which lack ODLRO, one can introduce a restricted gauge transformation that removes the interaction of the conductor with the vector potential. Consequently, the AB effect on a beam particle is not shielded by the conductor.

  10. Reduced long-range functional connectivity in young children with autism spectrum disorder.

    PubMed

    Kikuchi, Mitsuru; Yoshimura, Yuko; Hiraishi, Hirotoshi; Munesue, Toshio; Hashimoto, Takanori; Tsubokawa, Tsunehisa; Takahashi, Tsutomu; Suzuki, Michio; Higashida, Haruhiro; Minabe, Yoshio

    2015-02-01

    Autism spectrum disorder (ASD) is often described as a disorder of aberrant neural connectivity. Although it is important to study the pathophysiology of ASD in the developing cortex, the functional connectivity in the brains of young children with ASD has not been well studied. In this study, brain activity was measured non-invasively during consciousness in 50 young human children with ASD and 50 age- and gender-matched typically developing human (TD) children. We employed a custom child-sized magnetoencephalography (MEG) system in which sensors were located as close to the brain as possible for optimal recording in young children. We focused on theta band oscillations because they are thought to be involved in long-range networks associated with higher cognitive processes. The ASD group showed significantly reduced connectivity between the left-anterior and the right-posterior areas, exhibiting a decrease in the coherence of theta band (6 Hz) oscillations compared with the TD group. This reduction in coherence was significantly correlated with clinical severity in right-handed children with ASD. This is the first study to demonstrate reduced long-range functional connectivity in conscious young children with ASD using a novel MEG approach. © The Author (2014). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

  11. Circadian waves of cytosolic calcium concentration and long-range network connections in rat suprachiasmatic nucleus.

    PubMed

    Hong, Jin Hee; Jeong, Byeongha; Min, Cheol Hong; Lee, Kyoung J

    2012-05-01

    The suprachiasmatic nucleus (SCN) is the master clock in mammals governing the daily physiological and behavioral rhythms. It is composed of thousands of clock cells with their own intrinsic periods varying over a wide range (20-28 h). Despite this heterogeneity, an intact SCN maintains a coherent 24 h periodic rhythm through some cell-to-cell coupling mechanisms. This study examined how the clock cells are connected to each other and how their phases are organized in space by monitoring the cytosolic free calcium ion concentration ([Ca(2+)](c)) of clock cells using the calcium-binding fluorescent protein, cameleon. Extensive analysis of 18 different organotypic slice cultures of the SCN showed that the SCN calcium dynamics is coordinated by phase-synchronizing networks of long-range neurites as well as by diffusively propagating phase waves. The networks appear quite extensive and far-reaching, and the clock cells connected by them exhibit heterogeneous responses in their amplitudes and periods of oscillation to tetrodotoxin treatments. Taken together, our study suggests that the network of long-range cellular connectivity has an important role for the SCN in achieving its phase and period coherence. © 2012 The Authors. European Journal of Neuroscience © 2012 Federation of European Neuroscience Societies and Blackwell Publishing Ltd.

  12. Reduced long-range functional connectivity in young children with autism spectrum disorder

    PubMed Central

    Yoshimura, Yuko; Hiraishi, Hirotoshi; Munesue, Toshio; Hashimoto, Takanori; Tsubokawa, Tsunehisa; Takahashi, Tsutomu; Suzuki, Michio; Higashida, Haruhiro; Minabe, Yoshio

    2015-01-01

    Autism spectrum disorder (ASD) is often described as a disorder of aberrant neural connectivity. Although it is important to study the pathophysiology of ASD in the developing cortex, the functional connectivity in the brains of young children with ASD has not been well studied. In this study, brain activity was measured non-invasively during consciousness in 50 young human children with ASD and 50 age- and gender-matched typically developing human (TD) children. We employed a custom child-sized magnetoencephalography (MEG) system in which sensors were located as close to the brain as possible for optimal recording in young children. We focused on theta band oscillations because they are thought to be involved in long-range networks associated with higher cognitive processes. The ASD group showed significantly reduced connectivity between the left-anterior and the right-posterior areas, exhibiting a decrease in the coherence of theta band (6 Hz) oscillations compared with the TD group. This reduction in coherence was significantly correlated with clinical severity in right-handed children with ASD. This is the first study to demonstrate reduced long-range functional connectivity in conscious young children with ASD using a novel MEG approach. PMID:24652855

  13. Long-range surface modes supported by thin films

    NASA Astrophysics Data System (ADS)

    Yang, Fuzi; Sambles, J. R.; Bradberry, G. W.

    1991-09-01

    A detailed analysis of the surface modes of a thin slab of material of dielectric constant ɛ2 (=ɛr2-iɛi2) surrounded symmetrically by dielectric media is presented. Results show that in the thin-film limit, as well as the well-known long-range surface plasmon for a thin metal layer and the TM guided mode for a thin dielectric, a long-range surface mode exists for almost any value of ɛ2. This is even true if the imaginary part of ɛ2, ɛi2, is much larger than the real part ɛr2. We also find that a long-range surface mode may arise from the coupling between two surfaces which individually cannot support a surface mode. These are a pair of special coupled-surface modes which may exist below a certain critical film thickness and which have two separate propagation vectors each with the same field symmetry. It is also found that the inverse situation may pertain, that is for certain relative values of dielectric constants even though ordinary surface modes may exist, below a critical thickness the resulting coupled long-range mode no longer exists. The analysis has also been extended to practical situations with weakly absorbing surrounding media and to circumstances where the dielectric constants of the surrounding media are slightly different. Both of these effects modify the dispersion relations obtained for the simple case and introduce further limit thicknesses into the problem. Analytic formulas in the thin-film limit are presented for all the above situations and field distributions and energy flow (Poynting vector) profiles presented to illustrate as necessary the nature of the modes supported by these systems. Finally experimental results are presented which illustrate the rather sweeping conclusion that a long-range surface mode may exist on a thin film for almost all values of ɛr2 and ɛi2. This result paves the way for a range of optics experiments on absorbing structures.

  14. Electronic coherence lineshapes reveal hidden excitonic correlations in photosynthetic light harvesting.

    PubMed

    Wong, Cathy Y; Alvey, Richard M; Turner, Daniel B; Wilk, Krystyna E; Bryant, Donald A; Curmi, Paul M G; Silbey, Robert J; Scholes, Gregory D

    2012-03-25

    The effective absorption cross-section of a molecule (acceptor) can be greatly increased by associating it with a cluster of molecules that absorb light and transfer the excitation energy to the acceptor molecule. The basic mechanism of such light harvesting by Förster resonance energy transfer (FRET) is well established, but recent experiments have revealed a new feature whereby excitation is coherently shared among donor and acceptor molecules during FRET. In the present study, two-dimensional electronic spectroscopy was used to examine energy transfer at ambient temperature in a naturally occurring light-harvesting protein (PE545 of the marine cryptophyte alga Rhodomonas sp. strain CS24). Quantum beating was observed across a range of excitation frequencies. The shapes of those features in the two-dimensional spectra were examined. Through simulations, we show that two-dimensional electronic spectroscopy provides a probe of the adiabaticity of the free energy landscape underlying light harvesting.

  15. Energy transport in the three coupled α-polypeptide chains of collagen molecule with long-range interactions effect

    NASA Astrophysics Data System (ADS)

    Mvogo, Alain; Ben-Bolie, G. H.; Kofané, T. C.

    2015-06-01

    The dynamics of three coupled α-polypeptide chains of a collagen molecule is investigated with the influence of power-law long-range exciton-exciton interactions. The continuum limit of the discrete equations reveal that the collagen dynamics is governed by a set of three coupled nonlinear Schrödinger equations, whose dispersive coefficient depends on the LRI parameter r. We construct the analytic symmetric and asymmetric (antisymmetric) soliton solutions, which match with the structural features of collagen related with the acupuncture channels. These solutions are used as initial conditions for the numerical simulations of the discrete equations, which reveal a coherent transport of energy in the molecule for r > 3. The results also indicate that the width of the solitons is a decreasing function of r, which help to stabilize the solitons propagating in the molecule. To confirm further the efficiency of energy transport in the molecule, the modulational instability of the system is performed and the numerical simulations show that the energy can flow from one polypeptide chain to another in the form of nonlinear waves.

  16. Acceleration of evolutionary spread by long-range dispersal

    PubMed Central

    Hallatschek, Oskar; Fisher, Daniel S.

    2014-01-01

    The spreading of evolutionary novelties across populations is the central element of adaptation. Unless populations are well mixed (like bacteria in a shaken test tube), the spreading dynamics depend not only on fitness differences but also on the dispersal behavior of the species. Spreading at a constant speed is generally predicted when dispersal is sufficiently short ranged, specifically when the dispersal kernel falls off exponentially or faster. However, the case of long-range dispersal is unresolved: Although it is clear that even rare long-range jumps can lead to a drastic speedup—as air-traffic–mediated epidemics show—it has been difficult to quantify the ensuing stochastic dynamical process. However, such knowledge is indispensable for a predictive understanding of many spreading processes in natural populations. We present a simple iterative scaling approximation supported by simulations and rigorous bounds that accurately predicts evolutionary spread, which is determined by a trade-off between frequency and potential effectiveness of long-distance jumps. In contrast to the exponential laws predicted by deterministic “mean-field” approximations, we show that the asymptotic spatial growth is according to either a power law or a stretched exponential, depending on the tails of the dispersal kernel. More importantly, we provide a full time-dependent description of the convergence to the asymptotic behavior, which can be anomalously slow and is relevant even for long times. Our results also apply to spreading dynamics on networks with a spectrum of long-range links under certain conditions on the probabilities of long-distance travel: These are relevant for the spread of epidemics. PMID:25368183

  17. Modelling control of epidemics spreading by long-range interactions

    PubMed Central

    Dybiec, Bartłomiej; Kleczkowski, Adam; Gilligan, Christopher A.

    2009-01-01

    We have studied the spread of epidemics characterized by a mixture of local and non-local interactions. The infection spreads on a two-dimensional lattice with the fixed nearest neighbour connections. In addition, long-range dynamical links are formed by moving agents (vectors). Vectors perform random walks, with step length distributed according to a thick-tail distribution. Two distributions are considered in this paper, an α-stable distribution describing self-similar vector movement, yet characterized by an infinite variance and an exponential power characterized by a large but finite variance. Such long-range interactions are hard to track and make control of epidemics very difficult. We also allowed for cryptic infection, whereby an infected individual on the lattice can be infectious prior to showing any symptoms of infection or disease. To account for such cryptic spread, we considered a control strategy in which not only detected, i.e. symptomatic, individuals but also all individuals within a certain control neighbourhood are treated upon the detection of disease. We show that it is possible to eradicate the disease by using such purely local control measures, even in the presence of long-range jumps. In particular, we show that the success of local control and the choice of the optimal strategy depend in a non-trivial way on the dispersal patterns of the vectors. By characterizing these patterns using the stability index of the α-stable distribution to change the power-law behaviour or the exponent characterizing the decay of an exponential power distribution, we show that infection can be successfully contained using relatively small control neighbourhoods for two limiting cases for long-distance dispersal and for vectors that are much more limited in their dispersal range. PMID:19126536

  18. Acceleration of evolutionary spread by long-range dispersal.

    PubMed

    Hallatschek, Oskar; Fisher, Daniel S

    2014-11-18

    The spreading of evolutionary novelties across populations is the central element of adaptation. Unless populations are well mixed (like bacteria in a shaken test tube), the spreading dynamics depend not only on fitness differences but also on the dispersal behavior of the species. Spreading at a constant speed is generally predicted when dispersal is sufficiently short ranged, specifically when the dispersal kernel falls off exponentially or faster. However, the case of long-range dispersal is unresolved: Although it is clear that even rare long-range jumps can lead to a drastic speedup--as air-traffic-mediated epidemics show--it has been difficult to quantify the ensuing stochastic dynamical process. However, such knowledge is indispensable for a predictive understanding of many spreading processes in natural populations. We present a simple iterative scaling approximation supported by simulations and rigorous bounds that accurately predicts evolutionary spread, which is determined by a trade-off between frequency and potential effectiveness of long-distance jumps. In contrast to the exponential laws predicted by deterministic "mean-field" approximations, we show that the asymptotic spatial growth is according to either a power law or a stretched exponential, depending on the tails of the dispersal kernel. More importantly, we provide a full time-dependent description of the convergence to the asymptotic behavior, which can be anomalously slow and is relevant even for long times. Our results also apply to spreading dynamics on networks with a spectrum of long-range links under certain conditions on the probabilities of long-distance travel: These are relevant for the spread of epidemics.

  19. Cross-correlation of long-range correlated series

    NASA Astrophysics Data System (ADS)

    Arianos, Sergio; Carbone, Anna

    2009-03-01

    A method for estimating the cross-correlation Cxy(τ) of long-range correlated series x(t) and y(t), at varying lags τ and scales n, is proposed. For fractional Brownian motions with Hurst exponents H1 and H2, the asymptotic expression for Cxy(τ) depends only on the lag τ (wide-sense stationarity) and scales as a power of n with exponent H1+H2 for \\tau \\rightarrow 0 . The method is illustrated on: (i) financial series, to show the leverage effect; (ii) genomic sequences, to estimate the correlations between structural parameters along the chromosomes.

  20. DIII-D tokamak long range plan. Revision 3

    SciTech Connect

    1992-08-01

    The DIII-D Tokamak Long Range Plan for controlled thermonuclear magnetic fusion research will be carried out with broad national and international participation. The plan covers: (1) operation of the DIII-D tokamak to conduct research experiments to address needs of the US Magnetic Fusion Program; (2) facility modifications to allow these new experiments to be conducted; and (3) collaborations with other laboratories to integrate DIII-D research into the national and international fusion programs. The period covered by this plan is 1 November 19983 through 31 October 1998.

  1. Anisotropic blockade using pendular long-range Rydberg molecules

    NASA Astrophysics Data System (ADS)

    Eiles, Matthew T.; Lee, Hyunwoo; Pérez-Ríos, Jesús; Greene, Chris H.

    2017-05-01

    We propose an experiment to demonstrate a blockade mechanism caused by long-range anisotropic interactions in an ultracold dipolar gas composed of the recently observed "butterfly" Rydberg molecules. At the blockade radius, the strong intermolecular interaction between two adjacent molecules shifts their molecular states out of resonance with the photoassociation laser, preventing their simultaneous excitation. When the molecules are prepared in a quasi-one-dimensional (Q1D) trap, the interaction's strength can be tuned via a weak external field. The molecular density thus depends strongly on the angle between the trap axis and the field. The available Rydberg and internal molecular states provide a wide range of tunability.

  2. A Long Range Science Rover For Future Mars Missions

    NASA Technical Reports Server (NTRS)

    Hayati, Samad

    1997-01-01

    This paper describes the design and implementation currently underway at the Jet Propulsion Laboratory of a long range science rover for future missions to Mars. The small rover prototype, called Rocky 7, is capable of long traverse. autonomous navigation. and science instrument control, carries three science instruments, and can be commanded from any computer platform and any location using the World Wide Web. In this paper we describe the mobility system, the sampling system, the sensor suite, navigation and control, onboard science instruments. and the ground command and control system.

  3. INEL D&D Long-Range Plan

    SciTech Connect

    Buckland, R.J.; Kenoyer, D.J.; Preussner, D.H.

    1993-10-01

    This Long-Range Plan presents the Decontamination and Decommissioning (D&D) Program planning status for facilities at the Idaho National Engineering Laboratory (INEL). The plan provides a general description of the D&D Program objectives, management criteria, and philosophy; discusses current activities; and documents the INEL D&D Program cost and schedule estimate projections for the next 15 years. appendices are included that provide INEL D&D project historical information and a comprehensive descriptive summary of each current surplus facility.

  4. Long-range Prediction of Examining Room Requirements

    PubMed Central

    Sumner, Andrew T.; Hsieh, Richard K. C.

    1972-01-01

    A quantitative methodology for predicting long-range examining room requirements of an orthopedic outpatient clinic is described. A simulation model of the clinic is used in an analysis of the sensitivity of four performance measures to changes in the clinic components, providing upper and lower boundaries for the component values and ranking the components by their importance. Regression equations relate the number of examining rooms to the performance measures, and an overall equation is constructed to predict examining room requirements as a function of weights assigned to the four measures. PMID:5072861

  5. ATHLETE Mobility Performance in Long-Range Traverse

    NASA Technical Reports Server (NTRS)

    Townsend, Julie

    2011-01-01

    The All-Terrain Hex-Limbed Extra-Terrestrial Explorer (ATHLETE) is a modular mobility and manipulation platform being developed to support NASA operations in a variety of missions, including exploration of planetary surfaces. The agile system consists of a symmetrical arrangement of six limbs, each with seven articulated degrees of freedom and a powered wheel. This design enables transport of bulky payloads over a wide range of terrains and is envisioned as a tool to mobilize habitats, power-generation equipment, and other supplies for long-range exploration and outpost construction.

  6. INEL D&D long-range plan

    SciTech Connect

    Buckland, R.J.; Kenoyer, D.J.; LaBuy, S.A.

    1995-09-01

    This Long-Range Plan presents the Decontamination and Dismantlement (D&D) Program planning status for facilities at the Idaho National Engineering Laboratory (INEL). The plan provides a general description of the D&D Program objectives, management criteria, and policy; discusses current activities; and documents the INEL D&D Program cost and schedule estimate projections for the next 15 years. Appendices are included that provide INEL D&D project historical information, a comprehensive descriptive summary of each current D&D surplus facility, and a summary database of all INEL contaminated facilities awaiting or undergoing the facility transition process.

  7. Application of advanced technology to future long-range aircraft

    NASA Technical Reports Server (NTRS)

    Schrader, O. E.

    1976-01-01

    An assessment is presented of three separate programs that have incorporated advanced technology into the design of long-range passenger and cargo aircraft. The first technology centers around the use of a span-loaded cargo aircraft with the payload distributed along the wing. The second technology is the application of laminar flow control to the aircraft to reduce the aerodynamic drag. The last program evaluates the production of alternate aircraft fuels from coal and the use of liquid hydrogen as an aircraft fuel.

  8. Restricted Boltzmann machines for the long range Ising models

    NASA Astrophysics Data System (ADS)

    Aoki, Ken-Ichi; Kobayashi, Tamao

    2016-12-01

    We set up restricted Boltzmann machines (RBM) to reproduce the long range Ising (LRI) models of the Ohmic type in one dimension. The RBM parameters are tuned by using the standard machine learning procedure with an additional method of configuration with probability (CwP). The quality of resultant RBM is evaluated through the susceptibility with respect to the magnetic external field. We compare the results with those by block decimation renormalization group (BDRG) method, and our RBM clear the test with satisfactory precision.

  9. Passive vibration isolation for long range aerial reconnaissance systems

    NASA Astrophysics Data System (ADS)

    Otoole, J.

    1980-01-01

    The paper discusses an approach to the design of a passive isolation system for a high-altitude, long-range oblique reconnaissance camera which works in conjunction with the active, gyro-stabilized system to attenuate a broad spectrum of vibratory inputs. The proposed design provides an elastic suspension system with minimum damping forces and a damping system which controls the excursions of the camera in the resonant region of disturbance; it has both spring and damping forces in complete balance about the center of gravity of the camera. Mathematical equations and definition in support of the proposed approach are presented together with some pertinent data.

  10. Hysteresis of long-range ordering in CuAu

    SciTech Connect

    Chalupa, B.; Chmelik, F.; Sima, V.; Sprusil, B.; Spanl, M.; Lang, H.; Pfeiler, W.

    1996-12-31

    The effect of heating and cooling on the long-range order transformation in stoichiometric CuAu is investigated by several complementary measuring methods. Measurements of heat flow, resistometry and acoustic emission are done dynamically by linear heating/cooling. It is shown that measuring dynamically yields the expected effect of undercooling, which decreases with decreasing cooling rate. The dependence of undercooling on cooling rate is compared with the concept of continuous cooling for glass forming. A small influence of heating rate on disordering temperature is reported (retro-effect).

  11. The design of a long range megatransport aircraft

    NASA Technical Reports Server (NTRS)

    Weisshaar, T. A.; Layton, J. B.; Allen, C. L.

    1993-01-01

    Megatransport objectives and constraints are briefly reviewed, and certain solutions developed by student design teams at Perdue University are summarized. Particular attention is given to the market needs and the economic risks involved in such a project; and the different approaches taken to solve the problem and difficulties faced by the design teams. A long range megatransport aircraft is aimed at carrying more than 600 passengers at reduced cost, and at the same time, reducing airport and airway congestion. The design effort must take into account airport terminal facilities; passenger loading and unloading; and defeating the 'square-cube' law to design large structures.

  12. Long-range attraction of particles adhered to lipid vesicles

    NASA Astrophysics Data System (ADS)

    Sarfati, Raphael; Dufresne, Eric R.

    2016-07-01

    Many biological systems fold thin sheets of lipid membrane into complex three-dimensional structures. This microscopic origami is often mediated by the adsorption and self-assembly of proteins on a membrane. As a model system to study adsorption-mediated interactions, we study the collective behavior of micrometric particles adhered to a lipid vesicle. We estimate the colloidal interactions using a maximum likelihood analysis of particle trajectories. When the particles are highly wrapped by a tense membrane, we observe strong long-range attractions with a typical binding energy of 150 kBT and significant forces extending a few microns.

  13. Hydrogen Atoms Cause Long-Range Electronic Effects on Graphite

    NASA Astrophysics Data System (ADS)

    Ruffieux, P.; Gröning, O.; Schwaller, P.; Schlapbach, L.; Gröning, P.

    2000-05-01

    We report on long-range electronic effects caused by hydrogen-carbon interaction at the graphite surface. Two types of defects could be distinguished with a combined mode of scanning tunneling microscopy and atomic force microscopy: chemisorption of hydrogen on the basal plane of graphite and atomic vacancy formation. Both types show a \\(3×3\\)R30° superlattice in the local density of states but have a different topographic structure. The range of modifications in the electronic structure, of fundamental importance for electronic devices based on carbon nanostructures, has been found to be of the order of 20-25 lattice constants.

  14. Political Mechanisms for Long-Range Survival and Development

    NASA Astrophysics Data System (ADS)

    Marshall, W.

    As the first species aware of extinction and capable of proactively ensuring our long-term survival and development, it is striking that we do not do so with the rigor, formality, and foresight it requires. Only from a reactive posture have we responded to the challenges of global warfare, human rights, environmental concerns, and sustainable development. Despite our awareness of the possibility for extinction and apocalyptic set-backs to our evolution, and despite the existence of long-range studies-which must still be dramatically increased-proactive global policy implementation regarding our long-term survival and development is arguably non-existent. This lack of long-term policy making can be attributed in part to the lack of formal political mechanisms to facilitate longer-range policy making that extends 30 years or more into the future. Political mechanisms for infusing long-range thinking, research, and strategic planning into the policy-making process can help correct this shortcoming and provide the motivation needed to adequately address long-term challenges with the political rigor required to effectively establish and implement long-term policies. There are some efforts that attempt to address longer-range issues, but those efforts often do not connect to the political process, do not extend 30 or more years into the future, are not well-funded, and are not sufficiently systemic. Political mechanisms for long-range survival and prosperity could correct these inadequacies by raising awareness, providing funding, and most importantly, leveraging political rigor to establish and enforce long-range strategic planning and policies. The feasibility of such mechanisms should first be rigorously studied and assessed in a feasibility study, which could then inform implementation. This paper will present the case for such a study and suggest some possible political mechanisms that should be investigated further in the proposed study. This work is being further

  15. Long Range Transport of War-Related Burn Casualties

    DTIC Science & Technology

    2008-02-01

    ted to the Army’s burn center between March 2003 and February 2007. Data in- cluded total body surface area (TBSA) burn, ventilatory status... total body surface area (range, ə%–95%) with a mean Injury Severity Score of 12.2 13.7. One hundred eight-one (33.5%) casualties required venti...Long Range Transport of War-Related Burn Casualties 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT

  16. ATHLETE Mobility Performance in Long-Range Traverse

    NASA Technical Reports Server (NTRS)

    Townsend, Julie

    2011-01-01

    The All-Terrain Hex-Limbed Extra-Terrestrial Explorer (ATHLETE) is a modular mobility and manipulation platform being developed to support NASA operations in a variety of missions, including exploration of planetary surfaces. The agile system consists of a symmetrical arrangement of six limbs, each with seven articulated degrees of freedom and a powered wheel. This design enables transport of bulky payloads over a wide range of terrains and is envisioned as a tool to mobilize habitats, power-generation equipment, and other supplies for long-range exploration and outpost construction.

  17. Anisotropic blockade using pendular long-range Rydberg molecules

    NASA Astrophysics Data System (ADS)

    Eiles, M. T.; Lee, H.; Pérez-Ríos, J.; Greene, C. H.

    2017-07-01

    We propose an experiment to demonstrate a novel blockade mechanism caused by long-range anisotropic interactions in an ultracold dipolar gas composed of the recently observed "butterfly" Rydberg molecules. At the blockade radius, the strong intermolecular interaction between two adjacent molecules shifts their molecular states out of resonance with the photoassociation laser, preventing their simultaneous excitation. When the molecules are prepared in a quasi-one-dimensional (Q1D) trap, the interaction's strength can be tuned via a weak external field. The molecular density thus depends strongly on the angle between the trap axis and the field. The available Rydberg and molecular states provide a wide range of tunability.

  18. Long-range exchange interaction between magnetic impurities in graphene

    NASA Astrophysics Data System (ADS)

    Agarwal, M.; Mishchenko, E. G.

    2017-02-01

    The effective spin exchange RKKY coupling between impurities (adatoms) on graphene mediated by conduction electrons is studied as a function of the strength of the potential part of the on-site energy U of the electron-adatom interaction. With increasing U , the exchange coupling becomes long range, determined largely by the impurity levels with energies close to the Dirac points. When adatoms reside on opposite sublattices, their exchange coupling, normally antiferromagnetic, becomes ferromagnetic and resonantly enhanced at a specific distance where an impurity level crosses the Dirac point.

  19. Long-range synchrony and emergence of neural reentry

    PubMed Central

    Keren, Hanna; Marom, Shimon

    2016-01-01

    Neural synchronization across long distances is a functionally important phenomenon in health and disease. In order to access the basis of different modes of long-range synchrony, we monitor spiking activities over centimetre scale in cortical networks and show that the mode of synchrony depends upon a length scale, λ, which is the minimal path that activity should propagate through to find its point of origin ready for reactivation. When λ is larger than the physical dimension of the network, distant neuronal populations operate synchronously, giving rise to irregularly occurring network-wide events that last hundreds of milliseconds to several seconds. In contrast, when λ approaches the dimension of the network, a continuous self-sustained reentry propagation emerges, a regular seizure-like mode that is marked by precise spatiotemporal patterns (‘synfire chains’) and may last many minutes. Termination of a reentry phase is preceded by a decrease of propagation speed to a halt. Stimulation decreases both propagation speed and λ values, which modifies the synchrony mode respectively. The results contribute to the understanding of the origin and termination of different modes of neural synchrony as well as their long-range spatial patterns, while hopefully catering to manipulation of the phenomena in pathological conditions. PMID:27874019

  20. Phase transitions in simplified models with long-range interactions

    NASA Astrophysics Data System (ADS)

    Rocha Filho, T. M.; Amato, M. A.; Mello, B. A.; Figueiredo, A.

    2011-10-01

    We study the origin of phase transitions in several simplified models with long-range interactions. For the self-gravitating ring model, we are unable to observe a possible phase transition predicted by Nardini and Casetti [Phys. Rev. EPLEEE81539-375510.1103/PhysRevE.80.060103 80, 060103R (2009).] from an energy landscape analysis. Instead we observe a sharp, although without any nonanalyticity, change from a core-halo to a core-only configuration in the spatial distribution functions for low energies. By introducing a different class of solvable simplified models without any critical points in the potential energy we show that a behavior similar to the thermodynamics of the ring model is obtained, with a first-order phase transition from an almost homogeneous high-energy phase to a clustered phase and the same core-halo to core configuration transition at lower energies. We discuss the origin of these features for the simplified models and show that the first-order phase transition comes from the maximization of the entropy of the system as a function of energy and an order parameter, as previously discussed by Hahn and Kastner [Phys. Rev. EPLEEE81539-375510.1103/PhysRevE.72.056134 72, 056134 (2005); Eur. Phys. J. BEPJBFY1434-602810.1140/epjb/e2006-00100-7 50, 311 (2006)], which seems to be the main mechanism causing phase transitions in long-range interacting systems.

  1. Long-range response in ac electricity grids

    NASA Astrophysics Data System (ADS)

    Jung, Daniel; Kettemann, Stefan

    2016-07-01

    Local changes in the topology of electricity grids can cause overloads far away from the disturbance [D. Witthaut and M. Timme, Eur. Phys. J. B 86, 377 (2013), 10.1140/epjb/e2013-40469-4], making the prediction of the robustness against changes in the topology—for example, caused by power outages or grid extensions—a challenging task. The impact of single-line additions on the long-range response of dc electricity grids has recently been studied [D. Labavić, R. Suciu, H. Meyer-Ortmanns, and S. Kettemann, Eur. Phys. J.: Spec. Top. 223, 2517 (2014), 10.1140/epjst/e2014-02273-0]. By solving the real part of the static ac load flow equations, we conduct a similar investigation for ac grids. In a regular two-dimensional grid graph with cyclic boundary conditions, we find a power law decay for the change of power flow as a function of distance to the disturbance over a wide range of distances. The power exponent increases and saturates for large system sizes. By applying the same analysis to the German transmission grid topology, we show that also in real-world topologies a long-ranged response can be found.

  2. Disordered Kitaev chains with long-range pairing

    NASA Astrophysics Data System (ADS)

    Cai, Xiaoming

    2017-03-01

    We study the competition of disorder and superconductivity for a generalized Kitaev model in incommensurate potentials. The generalized Kitaev model describes one dimensional spinless fermions with long-range p-wave superconducting pairing, which decays with distance l as a power law  ∼1/{{l}α} . We focus on the transition from the topological superconducting phase to the topologically trivial Anderson localized phase, and effects of the exponent α on this phase transition. In the topological superconducting phase, for a system under open boundary condition the amplitude of zero-mode Majorana fermion has a hybrid exponential-algebraic decay as the distance increases from the edge. In the Anderson localized phase, some single-particle states remain critical for very strong disorders and the number of critical states increases as α decreases. In addition, except for critical disorders, the correlation function always has an exponential decay at the short range and an algebraic decay at the long range. Phase transition points are also numerically determined and the topological phase transition happens earlier at a smaller disorder strength for a system with smaller α.

  3. Dolphin "packet" use during long-range echolocation tasks.

    PubMed

    Finneran, James J

    2013-03-01

    When echolocating, dolphins typically emit a single broadband "click," then wait to receive the echo before emitting another click. However, previous studies have shown that during long-range echolocation tasks, they may instead emit a burst, or "packet," of several clicks, then wait for the packet of echoes to return before emitting another packet of clicks. The reasons for the use of packets are unknown. In this study, packet use was examined by having trained bottlenose dolphins perform long-range echolocation tasks. The tasks featured "phantom" echoes produced by capturing the dolphin's outgoing echolocation clicks, convolving the clicks with an impulse response to create an echo waveform, and then broadcasting the delayed, scaled echo to the dolphin. Dolphins were trained to report the presence of phantom echoes or a change in phantom echoes. Target range varied from 25 to 800 m. At ranges below 75 m, the dolphins rarely used packets. As the range increased beyond 75 m, two of the three dolphins increasingly produced packets, while the third dolphin instead utilized very high click repetition rates. The use of click packets appeared to be governed more by echo delay (target range) than echo amplitude.

  4. Helioseismology with long-range dark matter-baryon interactions

    SciTech Connect

    Lopes, Ilídio; Panci, Paolo; Silk, Joseph E-mail: panci@iap.fr

    2014-11-10

    Assuming the existence of a primordial asymmetry in the dark sector, we study how long-range dark matter (DM)-baryon interactions, induced by the kinetic mixing of a new U(1) gauge boson and a photon, affect the evolution of the Sun and, in turn, the sound speed the profile obtained from helioseismology. Thanks to the explicit dependence on the exchanged momenta in the differential cross section (Rutherford-like scattering), we find that DM particles with a mass of ∼10 GeV, kinetic mixing parameter of the order of 10{sup –9}, and a mediator with a mass smaller than a few MeV improve the agreement between the best solar model and the helioseismic data without being excluded by direct detection experiments. In particular, the LUX detector will soon be able to either constrain or confirm our best-fit solar model in the presence of a dark sector with long-range interactions that reconcile helioseismology with thermal neutrino results.

  5. Emergent long-range magnetic ordering in manganite superlattices

    NASA Astrophysics Data System (ADS)

    Burganov, Bulat; Macke, Sebastian; Monkman, Eric; Adamo, Carolina; Shai, Daniel; Schlom, Darrell; Sawatzky, George; Shen, Kyle

    2015-03-01

    Complex oxides composed into atomically precise heterostructures host a plethora of new phenomena driven by interface effects, dimensionality, correlations and strain. An example is emergent ferromagnetism in the superlattices (SL) of LaMnO3/SrMnO3 and the dimensionality-driven metal insulator transition, still not well understood theoretically. We use soft x-ray scattering combined with SQUID magnetometry to determine the magnetic and orbital ordering in the (LaMnO3)2n /(SrMnO3)n SL for n =1,2,3,4. By composition this system is close to colossal-magnetoresistive La2/3Sr1/3MnO3, an FM metal below 400K. The system undergoes a metal-insulator transition with higher n and is believed to have a complex magnetic ordering. We observe an unexpected long-range order in the n =4 sample where the magnetic period is equal to two chemical periods. The observed half-order Bragg peaks show strong linear and no circular dichroism. The temperature and polarization dependence of reflectometry points towards alignment between A-type AFM orders in the neighboring LaMnO3 layers, which is very unusual and indicates a long range interaction acting across the thick SrMnO3 layers with nominally G-type spin configuration. We simulate the reflectometry data for several model spin configurations to further elucidate the nature of this ordering.

  6. The Frontiers of Nuclear Science: A Long-Range Plan

    SciTech Connect

    None, None

    2007-12-01

    In a letter dated July 17, 2006, the Department of Energy’s (DOE) Office of Science for Nuclear Physics and the National Science Foundation’s (NSF) Mathematical and Physical Sciences Directorate charged the Nuclear Science Advisory Committee (NSAC) to “conduct a study of the opportunities and priorities for U.S. nuclear physics research and recommend a long range plan that will provide a framework for coordinated advancement of the nation’s nuclear science research programs over the next decade.” This request set in motion a bottom-up review and forward look by the nuclear science community. With input from this community-wide process, a 59 member working group, which included the present NSAC members, gathered at the beginning of May, 2007, to develop guidance on how to optimize the future research directions for the field based on the projected resources outlined in the charge letter from DOE and NSF. A new long range plan—The Frontiers of Nuclear Science—grew out of this meeting. For the last decade, the top priority for nuclear science has been to utilize the flagship facilities that were built with investments by the nation in the 1980s and 1990s. Research with these facilities has led to many significant new discoveries that have changed our understanding of the world in which we live. But new discoveries demand new facilities, and the successes cannot continue indefinitely without new investment.

  7. Long-range response in ac electricity grids.

    PubMed

    Jung, Daniel; Kettemann, Stefan

    2016-07-01

    Local changes in the topology of electricity grids can cause overloads far away from the disturbance [D. Witthaut and M. Timme, Eur. Phys. J. B 86, 377 (2013)EPJBFY1434-602810.1140/epjb/e2013-40469-4], making the prediction of the robustness against changes in the topology-for example, caused by power outages or grid extensions-a challenging task. The impact of single-line additions on the long-range response of dc electricity grids has recently been studied [D. Labavić, R. Suciu, H. Meyer-Ortmanns, and S. Kettemann, Eur. Phys. J.: Spec. Top. 223, 2517 (2014)1951-635510.1140/epjst/e2014-02273-0]. By solving the real part of the static ac load flow equations, we conduct a similar investigation for ac grids. In a regular two-dimensional grid graph with cyclic boundary conditions, we find a power law decay for the change of power flow as a function of distance to the disturbance over a wide range of distances. The power exponent increases and saturates for large system sizes. By applying the same analysis to the German transmission grid topology, we show that also in real-world topologies a long-ranged response can be found.

  8. Coping With Climate Noise: Long Range Dependence and Weather Derivatives

    NASA Astrophysics Data System (ADS)

    Jewson, S.; Caballero, R.

    2002-12-01

    Random day-to-day changes in weather lead to random year-to-year fluctuations in monthly and seasonal means, a feature known as "climate noise". Such climate noise has direct economic impact on a wide variety of businesses. A typical example is energy vendors, whose annual revenues are closely correlated with seasonal mean temperatures. To deal with this risk, a form of insurance known as weather derivatives has been developed in recent years. We discuss a Monte Carlo approach to the pricing of weather derivatives based on stochastic modeling of daily temperature. It will be shown that this approach can only be succesful if the time-series model correctly captures the autocorrelation structure of the data even at very high lags. Evidence will be presented that observed daily temperatures exhibit long-range dependence, i.e. power-law decay of the autocorrelation. This means that classical Box-Jenkins ARMA models are unequal to the task, since their autocorrelations decay exponentially. A generalisation of ARMA models which explicitly includes long-range dependence does however prove to be suitable, at least in some cases. We also briefly discuss the physical mechanisms which give rise to the long memory found in the data.

  9. An analysis of foliage effects on long-range surveillance

    NASA Astrophysics Data System (ADS)

    Hogan, D. L.

    1980-04-01

    Visibility is one of the key factors in determining the outcome of battles. With the advent of long range, moving target, air to ground surveillance radars, the motion of both the observing platform and the target have added to the visibility problem, which heretofore was analyzed in terms of shielding. The interaction of such factors as the minimum detectable velocity of the target, the trajectories of the target and the airborne radar platform, and the terrain and foliage masking combine to control the amount of time which a target is observed in a given scenario. This report continues the work done on dynamic masking, compares the masking calculation with and without foliage on a typical super highway in New England, and finally examines the correlation between predicted and observed foliage and terrain masking. The work was done in connection with the test and evaluation of the Multiple Antenna Surveillance Radar (MASR), a scaled model of a long range moving target surveillance system. MASR operated at L-band with a beamwidth of approximately 4.5 deg. In typical flight operation it observed the target complex from a range of 25 to 40 km. The altitude was selected to give lookdown angles ranging from 3 deg to 6 deg.

  10. Surface tension and long range corrections of cylindrical interfaces.

    PubMed

    Bourasseau, E; Malfreyt, P; Ghoufi, A

    2015-12-21

    The calculation of the surface tension of curved interfaces has been deeply investigated from molecular simulation during this last past decade. Recently, the thermodynamic Test-Area (TA) approach has been extended to the calculation of surface tension of curved interfaces. In the case of the cylindrical vapour-liquid interfaces of water and Lennard-Jones fluids, it was shown that the surface tension was independent of the curvature of the interface. In addition, the surface tension of the cylindrical interface is higher than that of the planar interface. Molecular simulations of cylindrical interfaces have been so far performed (i) by using a shifted potential, (ii) by means of large cutoff without periodic boundary conditions, or (iii) by ignoring the long range corrections to the surface tension due to the difficulty to estimate them. Indeed, unlike the planar interfaces there are no available operational expressions to consider the tail corrections to the surface tension of cylindrical interfaces. We propose here to develop the long range corrections of the surface tension for cylindrical interfaces by using the non-exponential TA (TA2) method. We also extend the formulation of the Mecke-Winkelmann corrections initially developed for planar surfaces to cylindrical interfaces. We complete this study by the calculation of the surface tension of cylindrical surfaces of liquid tin and copper using the embedded atom model potentials.

  11. On the Long-Range Directed Polymer Model

    NASA Astrophysics Data System (ADS)

    Wei, Ran

    2016-10-01

    We study the long-range directed polymer model on Z in a random environment, where the underlying random walk lies in the domain of attraction of an α -stable process for some α in (0,2]. Similar to the more classic nearest-neighbor directed polymer model, as the inverse temperature β increases, the model undergoes a transition from a weak disorder regime to a strong disorder regime. We extend most of the important results known for the nearest-neighbor directed polymer model on Z^d to the long-range model on Z. More precisely, we show that in the entire weak disorder regime, the polymer satisfies an analogue of invariance principle, while in the so-called very strong disorder regime, the polymer end point distribution contains macroscopic atoms and under some mild conditions, the polymer has a super-α -stable motion. Furthermore, for α in (1,2], we show that the model is in the very strong disorder regime whenever β >0, and we give explicit bounds on the free energy.

  12. Surface tension and long range corrections of cylindrical interfaces

    SciTech Connect

    Bourasseau, E.; Ghoufi, A.

    2015-12-21

    The calculation of the surface tension of curved interfaces has been deeply investigated from molecular simulation during this last past decade. Recently, the thermodynamic Test-Area (TA) approach has been extended to the calculation of surface tension of curved interfaces. In the case of the cylindrical vapour-liquid interfaces of water and Lennard-Jones fluids, it was shown that the surface tension was independent of the curvature of the interface. In addition, the surface tension of the cylindrical interface is higher than that of the planar interface. Molecular simulations of cylindrical interfaces have been so far performed (i) by using a shifted potential, (ii) by means of large cutoff without periodic boundary conditions, or (iii) by ignoring the long range corrections to the surface tension due to the difficulty to estimate them. Indeed, unlike the planar interfaces there are no available operational expressions to consider the tail corrections to the surface tension of cylindrical interfaces. We propose here to develop the long range corrections of the surface tension for cylindrical interfaces by using the non-exponential TA (TA2) method. We also extend the formulation of the Mecke-Winkelmann corrections initially developed for planar surfaces to cylindrical interfaces. We complete this study by the calculation of the surface tension of cylindrical surfaces of liquid tin and copper using the embedded atom model potentials.

  13. Long-range synchrony and emergence of neural reentry

    NASA Astrophysics Data System (ADS)

    Keren, Hanna; Marom, Shimon

    2016-11-01

    Neural synchronization across long distances is a functionally important phenomenon in health and disease. In order to access the basis of different modes of long-range synchrony, we monitor spiking activities over centimetre scale in cortical networks and show that the mode of synchrony depends upon a length scale, λ, which is the minimal path that activity should propagate through to find its point of origin ready for reactivation. When λ is larger than the physical dimension of the network, distant neuronal populations operate synchronously, giving rise to irregularly occurring network-wide events that last hundreds of milliseconds to several seconds. In contrast, when λ approaches the dimension of the network, a continuous self-sustained reentry propagation emerges, a regular seizure-like mode that is marked by precise spatiotemporal patterns (‘synfire chains’) and may last many minutes. Termination of a reentry phase is preceded by a decrease of propagation speed to a halt. Stimulation decreases both propagation speed and λ values, which modifies the synchrony mode respectively. The results contribute to the understanding of the origin and termination of different modes of neural synchrony as well as their long-range spatial patterns, while hopefully catering to manipulation of the phenomena in pathological conditions.

  14. The ORNL Surplus Facilities Management Program Long Range Plan

    SciTech Connect

    Myrick, T.E.

    1984-09-01

    The Surplus Facilities Management Program (SFMP) at Oak Ridge National Laboratory (ORNL) is part of the Department of Energy`s (DOE) National SFMP, administered by the Richland Operations Office. This program was established to provide for the management of DOE surplus radioactively contaminated facilities from the end of their operating life until final facility disposition is completed. As part of this program, the ORNL SFMP oversees some 76 individual surplus facilities, ranging in complexity from abandoned waste storage tanks to large experimental reactors. The ORNL SFMP has prepared this Long Range Plan to outline the long-term management strategy for those facilities included in the program. The primary objective of this plan are to: (1) develop a base of information for each ORNL SFMP facility, (2) conduct preliminary decommissioning analyses to identify feasible alternatives, (3) assess the current and future risk of each facility, (4) establish a priority list for the decommissioning projects, and (5) integrate the individual project costs and schedules into an overall program schedule and cost estimate for the ORNL site. The Long Range Plan also provides an overview of the ORNL SFMP management structure, specifies the decommissioning criteria to be employed, and identifies special technical problems, research and development needs, and special facilities and equipment that may be required for decommissioning operations.

  15. One-dimensional long-range percolation: A numerical study

    NASA Astrophysics Data System (ADS)

    Gori, G.; Michelangeli, M.; Defenu, N.; Trombettoni, A.

    2017-07-01

    In this paper we study bond percolation on a one-dimensional chain with power-law bond probability C /rd +σ , where r is the distance length between distinct sites and d =1 . We introduce and test an order-N Monte Carlo algorithm and we determine as a function of σ the critical value Cc at which percolation occurs. The critical exponents in the range 0 <σ <1 are reported. Our analysis is in agreement, up to a numerical precision ≈10-3 , with the mean-field result for the anomalous dimension η =2 -σ , showing that there is no correction to η due to correlation effects. The obtained values for Cc are compared with a known exact bound, while the critical exponent ν is compared with results from mean-field theory, from an expansion around the point σ =1 and from the ɛ -expansion used with the introduction of a suitably defined effective dimension deff relating the long-range model with a short-range one in dimension deff. We finally present a formulation of our algorithm for bond percolation on general graphs, with order N efficiency on a large class of graphs including short-range percolation and translationally invariant long-range models in any spatial dimension d with σ >0 .

  16. Adaptive optics instrument for long-range imaging. Final report

    SciTech Connect

    Crawford, T.M.

    1998-06-01

    The science and history of imaging through a turbulent atmosphere is reviewed in detail. Traditional methods for reducing the effects of turbulence are presented. A simplified method for turbulence reduction called the Sheared Coherent Interferometric Photography (SCIP) method is presented. Implementation of SCIP is discussed along with experimental results. Limitations in the use of this method are discussed along with recommendations for future improvements.

  17. Reservoir shore development in long range terrestrial laser scanning monitoring.

    NASA Astrophysics Data System (ADS)

    Kaczmarek, Halina

    2016-04-01

    Shore zones of reservoirs are in most cases very active, getting transformed as a result of coastal processes and mass movements initiated on the slopes surrounding the reservoir. From the point of view of the users of water reservoirs shore recession strongly undesirable as it causes destruction to infrastructure and buildings located in the immediate vicinity of the reservoir. For this reason, reservoir shores require continuous geodetic monitoring. Fast and accurate geodetic measurements covering shore sections several kilometers long, often in poorly accessible areas, are available using long range terrestrial laser scanning (TLS). The possibilities of using long range terrestrial laser scanning are shown on the example of the reservoir Jeziorsko on the Warta River (Central Poland). This reservoir, created in the years 1986-1992, is a typical retention reservoir, the annual fluctuations of which reach 5 m. Depending on the water level its surface area ranges from 42.3 to 19.6 km2. The width of the reservoir is 2.5 km. The total shore length of the reservoir, developed in Quaternary till and sand-till sediments, is 44.3 km, including 30.1 km of the unreinforced shore. Out of the unreinforced shore 27% is subject to coastal erosion. The cliff heights vary from a few cm to 12.5 meters, and the current rate of the cliff recession ranges from 0 to 1.12 m/y. The study used a terrestrial long range laser scanner Riegl VZ-4000 of a range of up to 4000 m. It enabled conducting the measurements of the cliff recession from the opposite shore of the reservoir, with an angular resolution of 0.002°, which gives about 50 measurement points per 1 m2. The measurements were carried out in the years 2014-2015, twice a year, in early spring before high water level, and in late autumn at a dropping water level. This allowed the separation of the impact of coastal processes and frost weathering on the cliff recession and their quantitative determination. The size and nature of

  18. Parallelized Stochastic Cutoff Method for Long-Range Interacting Systems

    NASA Astrophysics Data System (ADS)

    Endo, Eishin; Toga, Yuta; Sasaki, Munetaka

    2015-07-01

    We present a method of parallelizing the stochastic cutoff (SCO) method, which is a Monte-Carlo method for long-range interacting systems. After interactions are eliminated by the SCO method, we subdivide a lattice into noninteracting interpenetrating sublattices. This subdivision enables us to parallelize the Monte-Carlo calculation in the SCO method. Such subdivision is found by numerically solving the vertex coloring of a graph created by the SCO method. We use an algorithm proposed by Kuhn and Wattenhofer to solve the vertex coloring by parallel computation. This method was applied to a two-dimensional magnetic dipolar system on an L × L square lattice to examine its parallelization efficiency. The result showed that, in the case of L = 2304, the speed of computation increased about 102 times by parallel computation with 288 processors.

  19. Long range p -wave proximity effect into a disordered metal

    NASA Astrophysics Data System (ADS)

    Keser, Aydin Cem; Stanev, Valentin; Galitski, Victor

    2015-03-01

    We use quasiclassical methods of superconductivity to study the superconducting proximity effect from a topological p -wave superconductor into a disordered quasi-one-dimensional metallic wire. We demonstrate that the corresponding Eilenberger equations with disorder reduce to a closed nonlinear equation for the superconducting component of the matrix Green's function. Remarkably, this equation is formally equivalent to a classical mechanical system (i.e., Newton's equations), with the Green function corresponding to a coordinate of a fictitious particle and the coordinate along the wire corresponding to time. This mapping allows us to obtain exact solutions in the disordered nanowire in terms of elliptic functions. A surprising result that comes out of this solution is that the p -wave superconductivity proximity induced into the disordered metal remains long range, decaying as slowly as the conventional s -wave superconductivity. It is also shown that impurity scattering leads to the appearance of a zero-energy peak.

  20. Long-range effects in electron scattering by polar molecules

    NASA Astrophysics Data System (ADS)

    Fabrikant, Ilya I.

    2016-11-01

    We review long-range effects in electron collisions with polar molecules, starting with elastic scattering. We then go to rotationally and vibrationally inelastic processes and dissociative electron attachment. The last two are strongly affected by vibrational Feshbach resonances which have been observed and described theoretically in many systems from simple diatomic molecules to more complex polyatomics, biologically relevant molecules, and van der Waals clusters. We then review environmental effects which include electron interaction with molecules adsorbed on surfaces and molecules in cluster environments. We concentrate on physics rather than on listing results of ab initio calculations. With increasing complexity of targets and processes model approaches become more relevant. We demonstrate their success in the theoretical description of electron attachment to polyatomic molecules and to molecules in complex environments.

  1. Bias Reduction and Filter Convergence for Long Range Stereo

    NASA Technical Reports Server (NTRS)

    Sibley, Gabe; Matthies, Larry; Sukhatme, Gaurav

    2005-01-01

    We are concerned here with improving long range stereo by filtering image sequences. Traditionally, measurement errors from stereo camera systems have been approximated as 3-D Gaussians, where the mean is derived by triangulation and the covariance by linearized error propagation. However, there are two problems that arise when filtering such 3-D measurements. First, stereo triangulation suffers from a range dependent statistical bias; when filtering this leads to over-estimating the true range. Second, filtering 3-D measurements derived via linearized error propagation leads to apparent filter divergence; the estimator is biased to under-estimate range. To address the first issue, we examine the statistical behavior of stereo triangulation and show how to remove the bias by series expansion. The solution to the second problem is to filter with image coordinates as measurements instead of triangulated 3-D coordinates.

  2. An evaluation methodology for long-range jammer to CCD

    NASA Astrophysics Data System (ADS)

    Zhang, Wen-pan; Ren, Guang-sen; Wang, Yan-bin; Li, Hua; Zhu, Rong-zhen

    2015-11-01

    By analyzing the factors of laser transmission from long-range jammer to CCD in the distribution of laser at the entrance of optical system of CCD, an evaluation methodology was established which utilized the ATP error data and the distribution of laser through turbulent atmosphere together and could get the jamming probability which could be used to get evaluation result. A conversion method was devised to convert test data to simulation data of ATP. Based on circular aperture Fraunhofer diffraction theory, a simplified model that only used the central bright patch was provided to convert the relationship between the number of saturated pixel and the incident laser energy by testing to the relationship in simulation. Some advice was given for the usage of test data of ATP and the relationship between the number of saturated pixel and the incident laser energy by testing to make sure that the data is available.

  3. Traveling solitons in long-range oscillator chains

    NASA Astrophysics Data System (ADS)

    Miloshevich, George; Nguenang, Jean Pierre; Dauxois, Thierry; Khomeriki, Ramaz; Ruffo, Stefano

    2017-03-01

    We investigate the existence and propagation of solitons in a long-range extension of the quartic Fermi–Pasta–Ulam (FPU) chain of anharmonic oscillators. The coupling in the linear term decays as a power-law with an exponent 1<α ≤slant 3 . We obtain an analytic perturbative expression of traveling envelope solitons by introducing a non linear Schrödinger equation for the slowly varying amplitude of short wavelength modes. Due to the non analytic properties of the dispersion relation, it is crucial to develop the theory using discrete difference operators. Those properties are also the ultimate reason why kink-solitons may exist but are unstable, at variance with the short-range FPU model. We successfully compare these approximate analytic results with numerical simulations for the value α =2 which was chosen as a case study.

  4. Sparse labeling of proteins: Structural characterization from long range constraints

    NASA Astrophysics Data System (ADS)

    Prestegard, James H.; Agard, David A.; Moremen, Kelley W.; Lavery, Laura A.; Morris, Laura C.; Pederson, Kari

    2014-04-01

    Structural characterization of biologically important proteins faces many challenges associated with degradation of resolution as molecular size increases and loss of resolution improving tools such as perdeuteration when non-bacterial hosts must be used for expression. In these cases, sparse isotopic labeling (single or small subsets of amino acids) combined with long range paramagnetic constraints and improved computational modeling offer an alternative. This perspective provides a brief overview of this approach and two discussions of potential applications; one involving a very large system (an Hsp90 homolog) in which perdeuteration is possible and methyl-TROSY sequences can potentially be used to improve resolution, and one involving ligand placement in a glycosylated protein where resolution is achieved by single amino acid labeling (the sialyltransferase, ST6Gal1). This is not intended as a comprehensive review, but as a discussion of future prospects that promise impact on important questions in the structural biology area.

  5. The effect of long-range interactions in DNA melting

    NASA Astrophysics Data System (ADS)

    Santos, Aaron; Klein`, William

    2014-03-01

    A theoretical understanding of the DNA melting transition may provide insight into the biological mechanisms of transcription and replication. If this process occurs via nucleation, it should exhibit several key features: metastability, rapid spontaneous growth, and droplet formation. In this talk, I describe the results of recent computational and theoretical studies on nearest-neighbor and long-range DNA models. While the models exhibit some characteristics of classical nucleation when the interaction range is short, they may undergo spinodal nucleation when the interaction range is long. In contrast to classical nucleation droplets, which are compact, spinodal critical droplets are diffuse, fractal-like, and similar to the metastable state. These results have clear implications for transcription and replication in biological DNA.

  6. Stable swarming using adaptive long-range interactions

    NASA Astrophysics Data System (ADS)

    Gorbonos, Dan; Gov, Nir S.

    2017-04-01

    Sensory mechanisms in biology, from cells to humans, have the property of adaptivity, whereby the response produced by the sensor is adapted to the overall amplitude of the signal, reducing the sensitivity in the presence of strong stimulus, while increasing it when it is weak. This property is inherently energy consuming and a manifestation of the nonequilibrium nature of living organisms. We explore here how adaptivity affects the effective forces that organisms feel due to others in the context of a uniform swarm, in both two and three dimensions. The interactions between the individuals are taken to be attractive and long-range and of power-law form. We find that the effects of adaptivity inside the swarm are dramatic, where the effective forces decrease (or remain constant) with increasing swarm density. Linear stability analysis demonstrates how this property prevents collapse (Jeans instability), when the forces are adaptive. Adaptivity therefore endows swarms with a natural mechanism for self-stabilization.

  7. Position-insensitive long range inductive power transfer

    NASA Astrophysics Data System (ADS)

    Kwan, Christopher H.; Lawson, James; Yates, David C.; Mitcheson, Paul D.

    2014-11-01

    This paper presents results of an improved inductive wireless power transfer system for reliable long range powering of sensors with milliwatt-level consumption. An ultra-low power flyback impedance emulator operating in open loop is used to present the optimal load to the receiver's resonant tank. Transmitter power modulation is implemented in order to maintain constant receiver power and to prevent damage to the receiver electronics caused by excessive received voltage. Received power is steady up to 3 m at around 30 mW. The receiver electronics and feedback system consumes 3.1 mW and so with a transmitter input power of 163.3 W the receiver becomes power neutral at 4.75 m. Such an IPT system can provide a reliable alternative to energy harvesters for supplying power concurrently to multiple remote sensors.

  8. Challenges in miniaturized automotive long-range lidar system design

    NASA Astrophysics Data System (ADS)

    Fersch, Thomas; Weigel, Robert; Koelpin, Alexander

    2017-05-01

    This paper discusses the current technical limitations posed on endeavors to miniaturize lidar systems for use in automotive applications and how to possibly extend those limits. The focus is set on long-range scanning direct time of flight LiDAR systems using APD photodetectors. Miniaturization evokes severe problems in ensuring absolute laser safety while maintaining the systems' performance in terms of maximum range, signal-to-noise ratio, detection probability, pixel density, or frame rate. Based on hypothetical but realistic specifications for an exemplary system the complete lidar signal path is calculated. The maximum range of the system is used as a general performance indicator. It is determined with the minimum signal-to-noise ratio required to detect an object. Various system parameters are varied to find their impact on the system's range. The reduction of the laser's pulse width and the right choice for the transimpedance amplifier's amplification have shown to be practicable measures to double the system's range.

  9. Long-range interactions in antiferromagnetic quantum spin chains

    NASA Astrophysics Data System (ADS)

    Bravo, B.; Cabra, D. C.; Gómez Albarracín, F. A.; Rossini, G. L.

    2017-08-01

    We study the role of long-range dipolar interactions on antiferromagnetic spin chains, from the classical S →∞ limit to the deep quantum case S =1 /2 , including a transverse magnetic field. To this end, we combine different techniques such as classical energy minima, classical Monte Carlo, linear spin waves, bosonization, and density matrix renormalization group (DMRG). We find a phase transition from the already reported dipolar ferromagnetic region to an antiferromagnetic region for high enough antiferromagnetic exchange. Thermal and quantum fluctuations destabilize the classical order before reaching magnetic saturation in both phases, and also close to zero field in the antiferromagnetic phase. In the extreme quantum limit S =1 /2 , extensive DMRG computations show that the main phases remain present with transition lines to saturation significatively shifted to lower fields, in agreement with the bosonization analysis. The overall picture maintains a close analogy with the phase diagram of the anisotropic XXZ spin chain in a transverse field.

  10. Vlasov equation for long-range interactions on a lattice.

    PubMed

    Bachelard, R; Dauxois, T; De Ninno, G; Ruffo, S; Staniscia, F

    2011-06-01

    We show that, in the continuum limit, the dynamics of Hamiltonian systems defined on a lattice with long-range couplings is well described by the Vlasov equation. This equation can be linearized around the homogeneous state, and a dispersion relation, which depends explicitly on the Fourier modes of the lattice, can be derived. This allows one to compute the stability thresholds of the homogeneous state, which turns out to depend on the mode number. When this state is unstable, the growth rates are also functions of the mode number. Explicit calculations are performed for the α-Hamiltonian mean field model with 0≤α<1, for which the mean-field mode is always found to dominate the exponential growth. The theoretical predictions are successfully compared with numerical simulations performed on a finite lattice.

  11. Effective field theory for long-range properties of bottomonium

    NASA Astrophysics Data System (ADS)

    Krein, Gastão

    2017-03-01

    In this communication we present selected results from a recent study [N. Brambilla, G. Krein, J. Tarrús Castellà and A. Vairo, Phys. Rev. D 93, 054002 (2016)] of long-range properties of bottomonium. An analytical expression for the chromopolarizability of 1S bottomonium states is derived within the framework of potential nonrelativistic QCD (pNRQCD). Next, after integrating out the ultrasoft scale associated with the binding energy of bottomonium, the QCD trace anomaly is used to obtain the two-pion production amplitude for the chromopolarizability operator and the result is matched to a chiral effective field theory having bottomonium states and pions as degrees of freedom. We present results for the leading chiral logarithm correction to the mass of the 1S bottomonium and the van der Waals potential between two bottomonium states.

  12. Mechanism of long-range proton translocation along biological membranes.

    PubMed

    Medvedev, Emile S; Stuchebrukhov, Alexei A

    2013-02-14

    Recent experiments suggest that protons can travel along biological membranes up to tens of micrometers, but the mechanism of transport is unknown. To explain such a long-range proton translocation we describe a model that takes into account the coupled bulk diffusion that accompanies the migration of protons on the surface. We show that protons diffusing at or near the surface before equilibrating with the bulk desorb and re-adsorb at the surface thousands of times, giving rise to a power-law desorption kinetics. As a result, the decay of the surface protons occurs very slowly, allowing for establishing local gradient and local exchange, as was envisioned in the early local models of biological energy transduction.

  13. Disrupting long-range polar order with an electric field

    NASA Astrophysics Data System (ADS)

    Guo, Hanzheng; Liu, Xiaoming; Xue, Fei; Chen, Long-Qing; Hong, Wei; Tan, Xiaoli

    2016-05-01

    Electric fields are known to favor long-range polar order through the aligning of electric dipoles in relation to Coulomb's force. Therefore, it would be surprising to observe a disordered polar state induced from an ordered state by electric fields. Here we show such an unusual phenomenon in a polycrystalline oxide where electric fields induce a ferroelectric-to-relaxor phase transition. The nonergodic relaxor phase with disordered dipoles appears as an intermediate state under electric fields during polarization reversal of the ferroelectric phase. Using the phenomenological theory, the underlying mechanism for this unexpected behavior can be attributed to the slow kinetics of the ferroelectric-to-relaxor phase transition, as well as its competition against domain switching during electric reversal. The demonstrated material could also serve as a model system to study the transient stages in first-order phase transitions; the slow kinetics does not require the use of sophisticated ultrafast tools.

  14. Particle filter for long range radar in RUV

    NASA Astrophysics Data System (ADS)

    Romeo, Kevin; Willett, Peter; Bar-Shalom, Yaakov

    2014-06-01

    In this paper we present an approach for tracking with a high-bandwidth active radar in long range scenarios with 3-D measurements in r-u-v coordinates. The 3-D low-process-noise scenarios considered are much more difficult than the ones we have previously investigated where measurements were in 2-D (i.e., polar coordinates). We show that in these 3-D scenarios the extended Kalman filter and its variants are not desirable as they suffer from either major consistency problems or degraded range accuracy, and most flavors of particle filter suffer from a loss of diversity among particles after resampling. This leads to sample impoverishment and divergence of the filter. In the scenarios studied, this loss of diversity can be attributed to the very low process noise. However, a regularized particle filter is shown to avoid this diversity problem while producing consistent results. The regularization is accomplished using a modified version of the Epanechnikov kernel.

  15. Solid state long range surface plasmon polariton single mode lasers

    NASA Astrophysics Data System (ADS)

    Karami Keshmarzi, Elham; Tait, R. Niall; Berini, Pierre

    2013-10-01

    Incorporation of a solid-state gain medium in the cladding of a Long Range Surface Plasmon Polariton (LRSPP) waveguide in order to create a single-mode near-infrared laser source is proposed. LRSPP Bragg gratings based on stepping the width of the metal strip are used to form the laser's cavity. Three laser configurations are presented: The first 2 lasers employ DBRs (Distributed Bragg Reflectors) in ECL (External Cavity Laser) architecture while the third is based on the DFB (Distributed Feedback) configuration. All 3 configurations are thermally tunable by heating the gratings directly by injecting current. The lasers are convenient to fabricate leading to inexpensive sources that could be used in optical integrated circuits or waveguide biosensors.

  16. Heat Transport due to Long-Range Collisions.

    NASA Astrophysics Data System (ADS)

    Hollmann, Eric M.

    1999-11-01

    Cross-magnetic-field heat transport in a quiescent pure ion plasma is found to be diffusive, with measured thermal diffusivity \\chi which is independent of magnetic field strength B and plasma density n. The measured values of \\chi are up to 100 times larger than the ``classical'' thermal diffusivity \\chic = (16 √π / 15) (n barv b^2 ) r_c^2 ln (rc / b) ∝ n^1 B-2 T-1/2 expected from velocity-scattering collisions;(M.N. Rosenbluth et al., Phys. Rev. 109), 1 (1958). but are in quantitative agreement with the thermal diffusivity \\chiL = 0.49 ( n barv b^2 ) λ_D^2 ∝ n^0 B^0 T-1/2 recently predicted to result from long-range ``guiding center'' collisions.(D.H.E. Dubin et al., Phys. Rev. Lett. 78), 3868 (1997). In these long-range collisions, which occur in plasmas with λD > r_c, particles on well-separated field lines exchange parallel kinetic energy only. In the present experiments, the maximal impact parameters are ρ <= λ_D but in larger plasmas (with cross-field dimension L > 100 λ_D) the emission and absorption of plasma waves over impact parameters ρ <= L is predicted to give a further enhancement of the heat transport. The experiments are performed by heating (or cooling) the ions locally with a laser beam to create a thermal gradient. A second laser is then used to monitor the resulting radial heat flow. Remarkably, the ions are held in steady-state for periods of weeks by an applied ``rotating wall'' drive;(X.-P. Huang et al., Phys. Rev. Lett. 78), 875 (1997). this allows for accurate, repeatable heat transport measurements over a wide range of plasma parameters. To date, the thermal diffusivity has been measured over a range of 100 in density, 4 in magnetic field, and 10^4 in temperature; and it is found that long-range collisions dominate the heat transport over this entire range.(E.M. Hollmann et al., Phys. Rev. Lett. 82). 4930 (1999). Separate measurements of the perp-to-parallel thermal isotropization rates show that short-range velocity

  17. Fractional dynamics of systems with long-range interaction

    NASA Astrophysics Data System (ADS)

    Tarasov, Vasily E.; Zaslavsky, George M.

    2006-12-01

    We consider one-dimensional chain of coupled linear and nonlinear oscillators with long-range powerwise interaction defined by a term proportional to 1/∣ n - m∣ α+1 . Continuous medium equation for this system can be obtained in the so-called infrared limit when the wave number tends to zero. We construct a transform operator that maps the system of large number of ordinary differential equations of motion of the particles into a partial differential equation with the Riesz fractional derivative of order α, when 0 < α < 2. Few models of coupled oscillators are considered and their synchronized states and localized structures are discussed in details. Particularly, we discuss some solutions of time-dependent fractional Ginzburg-Landau (or nonlinear Schrodinger) equation.

  18. On the origin of long-range correlations in texts.

    PubMed

    Altmann, Eduardo G; Cristadoro, Giampaolo; Esposti, Mirko Degli

    2012-07-17

    The complexity of human interactions with social and natural phenomena is mirrored in the way we describe our experiences through natural language. In order to retain and convey such a high dimensional information, the statistical properties of our linguistic output has to be highly correlated in time. An example are the robust observations, still largely not understood, of correlations on arbitrary long scales in literary texts. In this paper we explain how long-range correlations flow from highly structured linguistic levels down to the building blocks of a text (words, letters, etc..). By combining calculations and data analysis we show that correlations take form of a bursty sequence of events once we approach the semantically relevant topics of the text. The mechanisms we identify are fairly general and can be equally applied to other hierarchical settings.

  19. Stable swarming using adaptive long-range interactions.

    PubMed

    Gorbonos, Dan; Gov, Nir S

    2017-04-01

    Sensory mechanisms in biology, from cells to humans, have the property of adaptivity, whereby the response produced by the sensor is adapted to the overall amplitude of the signal, reducing the sensitivity in the presence of strong stimulus, while increasing it when it is weak. This property is inherently energy consuming and a manifestation of the nonequilibrium nature of living organisms. We explore here how adaptivity affects the effective forces that organisms feel due to others in the context of a uniform swarm, in both two and three dimensions. The interactions between the individuals are taken to be attractive and long-range and of power-law form. We find that the effects of adaptivity inside the swarm are dramatic, where the effective forces decrease (or remain constant) with increasing swarm density. Linear stability analysis demonstrates how this property prevents collapse (Jeans instability), when the forces are adaptive. Adaptivity therefore endows swarms with a natural mechanism for self-stabilization.

  20. Theory of Long-Range Ultracold Atom-Molecule Photoassociation.

    PubMed

    Pérez-Ríos, Jesús; Lepers, Maxence; Dulieu, Olivier

    2015-08-14

    The creation of ultracold molecules is currently limited to diatomic species. In this Letter, we present a theoretical description of the photoassociation of ultracold atoms and molecules to create ultracold excited triatomic molecules, thus being a novel example of a light-assisted ultracold chemical reaction. The calculation of the photoassociation rate of an ultracold Cs_{2} molecule in its rovibrational ground state with an ultracold Cs atom at frequencies close to its resonant excitation is reported, based on the solution of the quantum dynamics involving the atom-molecule long-range interactions and assuming a model potential for the short-range physics. The rate for the formation of excited Cs_{3} molecules is predicted to be comparable with currently observed atom-atom photoassociation rates. We formulate an experimental proposal to observe this process relying on the available techniques of optical lattices and standard photoassociation spectroscopy.

  1. Stripe Glass from Competing Short and Long Range Interactions

    NASA Astrophysics Data System (ADS)

    Zimanyi, Gergely; Pike, Chris; Scalettar, Richard

    2006-03-01

    We investigate a film of dipoles oriented perpendicular to the film. The system's behavior is related to inhomogeneous non-Fermi liquid states, recently studied by Kivelson and Spivak and by Schmalian and Wolynes. The competition of short range ferromagnetic and long range antiferromagnetic interactions causes the formation of stripes. The system has an ordered stripe-crystal phase. However, this phase is avoided unless an extremely slow annealing protocol is utilized. Without any quenched disorder during normal annealing protocols the frustrated competing interactions self-generate a stripe-glass state. The stripe glass exhibits aging, manifesting itself in waiting-time dependent correlations. A scaling analysis of the aging is presented. The long time behavior shows stretched exponential behavior, the relaxation time surprisingly exhibiting a simple activated form. Dynamical inhomogeneities are identified, both frozen domains and instantaneous crystallites.

  2. Long-range correlations in quantum systems with aperiodic Hamiltonians

    NASA Astrophysics Data System (ADS)

    Lin, Zhifang; Goda, Masaki

    1997-03-01

    An efficient algorithm for the computation of correlation function (CF) at very long distances is presented for quantum systems whose Hamiltonian is formed by the substitution aperiodic sequence alternating over unit intervals in time or space. The algorithm reorganizes the expression of the CF in such a way that the evaluation of the CF at distances equal to some special numbers is related to a family of graphs generated recursively. As examples of applications, we evaluate the CF, over unprecedentedly long time intervals up to order of 1012, for aperiodic two-level systems subject to kicking perturbations that are in the Thue-Morse, the period-doubling, and the Rudin-Shapiro sequences, respectively. Our results show the presence of long-range correlations in all these aperiodic quantum systems.

  3. Long-Range Correlations of Global Sea Surface Temperature.

    PubMed

    Jiang, Lei; Zhao, Xia; Wang, Lu

    2016-01-01

    Scaling behaviors of the global monthly sea surface temperature (SST) derived from 1870-2009 average monthly data sets of Hadley Centre Sea Ice and SST (HadISST) are investigated employing detrended fluctuation analysis (DFA). The global SST fluctuations are found to be strong positively long-range correlated at all pertinent time-intervals. The value of scaling exponent is larger in the tropics than those in the intermediate latitudes of the northern and southern hemispheres. DFA leads to the scaling exponent α = 0.87 over the globe (60°S~60°N), northern hemisphere (0°N~60°N), and southern hemisphere (0°S~60°S), α = 0.84 over the intermediate latitude of southern hemisphere (30°S~60°S), α = 0.81 over the intermediate latitude of northern hemisphere (30°N~60°N) and α = 0.90 over the tropics 30°S~30°N [fluctuation F(s) ~ sα], which the fluctuations of monthly SST anomaly display long-term correlated behaviors. Furthermore, the larger the standard deviation is, the smaller long-range correlations (LRCs) of SST in the corresponding regions, especially in three distinct upwelling areas. After the standard deviation is taken into account, an index χ = α * σ is introduced to obtain the spatial distributions of χ. There exists an obvious change of global SST in central east and northern Pacific and the northwest Atlantic. This may be as a clue on predictability of climate and ocean variabilities.

  4. Two-Dimensional SIR Epidemics with Long Range Infection

    NASA Astrophysics Data System (ADS)

    Grassberger, Peter

    2013-10-01

    We extend a recent study of susceptible-infected-removed epidemic processes with long range infection (referred to as I in the following) from 1-dimensional lattices to lattices in two dimensions. As in I we use hashing to simulate very large lattices for which finite size effects can be neglected, in spite of the assumed power law p( x)˜| x|- σ-2 for the probability that a site can infect another site a distance vector x apart. As in I we present detailed results for the critical case, for the supercritical case with σ=2, and for the supercritical case with 0< σ<2. For the latter we verify the stretched exponential growth of the infected cluster with time predicted by M. Biskup. For σ=2 we find generic power laws with σ-dependent exponents in the supercritical phase, but no Kosterlitz-Thouless (KT) like critical point as in 1-d. Instead of diverging exponentially with the distance from the critical point, the correlation length increases with an inverse power, as in an ordinary critical point. Finally we study the dependence of the critical exponents on σ in the regime 0< σ<2, and compare with field theoretic predictions. In particular we discuss in detail whether the critical behavior for σ slightly less than 2 is in the short range universality class, as conjectured recently by F. Linder et al. As in I we also consider a modified version of the model where only some of the contacts are long range, the others being between nearest neighbors. If the number of the latter reaches the percolation threshold, the critical behavior is changed but the supercritical behavior stays qualitatively the same.

  5. Long-Range Correlations of Global Sea Surface Temperature

    PubMed Central

    Jiang, Lei; Zhao, Xia; Wang, Lu

    2016-01-01

    Scaling behaviors of the global monthly sea surface temperature (SST) derived from 1870–2009 average monthly data sets of Hadley Centre Sea Ice and SST (HadISST) are investigated employing detrended fluctuation analysis (DFA). The global SST fluctuations are found to be strong positively long-range correlated at all pertinent time-intervals. The value of scaling exponent is larger in the tropics than those in the intermediate latitudes of the northern and southern hemispheres. DFA leads to the scaling exponent α = 0.87 over the globe (60°S~60°N), northern hemisphere (0°N~60°N), and southern hemisphere (0°S~60°S), α = 0.84 over the intermediate latitude of southern hemisphere (30°S~60°S), α = 0.81 over the intermediate latitude of northern hemisphere (30°N~60°N) and α = 0.90 over the tropics 30°S~30°N [fluctuation F(s) ~ sα], which the fluctuations of monthly SST anomaly display long-term correlated behaviors. Furthermore, the larger the standard deviation is, the smaller long-range correlations (LRCs) of SST in the corresponding regions, especially in three distinct upwelling areas. After the standard deviation is taken into account, an index χ = α * σ is introduced to obtain the spatial distributions of χ. There exists an obvious change of global SST in central east and northern Pacific and the northwest Atlantic. This may be as a clue on predictability of climate and ocean variabilities. PMID:27100397

  6. Efficient Exciton Harvesting through Long-Range Energy Transfer.

    PubMed

    Wang, Yanbin; Ohkita, Hideo; Benten, Hiroaki; Ito, Shinzaburo

    2015-04-27

    Efficient exciton collection at charge-generation sites is one of the key requirements for the improvement in power conversion efficiency (PCE) of organic solar cells, because only excitons arriving at a donor/acceptor interface can be dissociated into free charge carriers. We evaluated the effective diffusion length in poly(3-hexylthiophene) (P3HT) by using donor/acceptor bilayers with two different exciton-quenching acceptors. One is an insoluble fullerene polymer (p-PCBVB), which is an efficient electron-accepting material with negligible absorption in the visible region. The other is a low-bandgap polymer, poly[(4,4-bis(2-ethylhexyl)-dithieno[3,2-b:2',3'-d]silole)-2,6-diyl-alt-(2,1,3-benzothiadiazole)-4,7-diyl], (PSBTBT). This polymer has a large absorption band in the near-IR region, which overlaps well with the emission band of P3HT. The effective diffusion length of P3HT excitons is evaluated to be 15 nm for P3HT/p-PCBVB bilayers and improved to 30 nm for P3HT/PSBTBT bilayers. This improvement is ascribed to long-range energy transfer from P3HT to PSBTBT. This finding suggests that the effective diffusion length of P3HT excitons can be increased through long-range energy transfer by incorporating PSBTBT into P3HT/PCBM blends. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Electromagnetically induced transparency of ultra-long-range Rydberg molecules

    NASA Astrophysics Data System (ADS)

    Mirgorodskiy, Ivan; Christaller, Florian; Braun, Christoph; Paris-Mandoki, Asaf; Tresp, Christoph; Hofferberth, Sebastian

    2017-07-01

    We study the impact of Rydberg molecule formation on the storage and retrieval of Rydberg polaritons in an ultracold atomic medium. We observe coherent revivals appearing in the storage and retrieval efficiency of stored photons that originate from simultaneous excitation of Rydberg atoms and Rydberg molecules in the system with subsequent interference between the possible storage paths. We show that over a large range of principal quantum numbers the observed results can be described by a two-state model including only the atomic Rydberg state and the Rydberg dimer molecule state. At higher principal quantum numbers the influence of polyatomic molecules becomes relevant and the dynamics of the system undergoes a transition from coherent evolution of a few-state system to an effective dephasing into a continuum of molecular states.

  8. Long-range correlations in the diffuse seismic coda.

    PubMed

    Campillo, Michel; Paul, Anne

    2003-01-24

    The late seismic coda may contain coherent information about the elastic response of Earth. We computed the correlations of the seismic codas of 101 distant earthquakes recorded at stations that were tens of kilometers apart. By stacking cross-correlation functions of codas, we found a low-frequency coherent part in the diffuse field. The extracted pulses have the polarization characteristics and group velocities expected for Rayleigh and Love waves. The set of cross-correlations has the symmetries of the surface-wave part of the Green tensor. This seismological example shows that diffuse waves produced by distant sources are sufficient to retrieve direct waves between two perfectly located points of observation. Because it relies on general properties of diffuse waves, this result has potential applications in other fields.

  9. Multiparametric, Longitudinal Optical Coherence Tomography Imaging Reveals Acute Injury and Chronic Recovery in Experimental Ischemic Stroke

    PubMed Central

    Srinivasan, Vivek J.; Mandeville, Emiri T.; Can, Anil; Blasi, Francesco; Climov, Mihail; Daneshmand, Ali; Lee, Jeong Hyun; Yu, Esther; Radhakrishnan, Harsha; Lo, Eng H.; Sakadžić, Sava; Eikermann-Haerter, Katharina; Ayata, Cenk

    2013-01-01

    Progress in experimental stroke and translational medicine could be accelerated by high-resolution in vivo imaging of disease progression in the mouse cortex. Here, we introduce optical microscopic methods that monitor brain injury progression using intrinsic optical scattering properties of cortical tissue. A multi-parametric Optical Coherence Tomography (OCT) platform for longitudinal imaging of ischemic stroke in mice, through thinned-skull, reinforced cranial window surgical preparations, is described. In the acute stages, the spatiotemporal interplay between hemodynamics and cell viability, a key determinant of pathogenesis, was imaged. In acute stroke, microscopic biomarkers for eventual infarction, including capillary non-perfusion, cerebral blood flow deficiency, altered cellular scattering, and impaired autoregulation of cerebral blood flow, were quantified and correlated with histology. Additionally, longitudinal microscopy revealed remodeling and flow recovery after one week of chronic stroke. Intrinsic scattering properties serve as reporters of acute cellular and vascular injury and recovery in experimental stroke. Multi-parametric OCT represents a robust in vivo imaging platform to comprehensively investigate these properties. PMID:23940761

  10. Multiparametric, longitudinal optical coherence tomography imaging reveals acute injury and chronic recovery in experimental ischemic stroke.

    PubMed

    Srinivasan, Vivek J; Mandeville, Emiri T; Can, Anil; Blasi, Francesco; Climov, Mihail; Daneshmand, Ali; Lee, Jeong Hyun; Yu, Esther; Radhakrishnan, Harsha; Lo, Eng H; Sakadžić, Sava; Eikermann-Haerter, Katharina; Ayata, Cenk

    2013-01-01

    Progress in experimental stroke and translational medicine could be accelerated by high-resolution in vivo imaging of disease progression in the mouse cortex. Here, we introduce optical microscopic methods that monitor brain injury progression using intrinsic optical scattering properties of cortical tissue. A multi-parametric Optical Coherence Tomography (OCT) platform for longitudinal imaging of ischemic stroke in mice, through thinned-skull, reinforced cranial window surgical preparations, is described. In the acute stages, the spatiotemporal interplay between hemodynamics and cell viability, a key determinant of pathogenesis, was imaged. In acute stroke, microscopic biomarkers for eventual infarction, including capillary non-perfusion, cerebral blood flow deficiency, altered cellular scattering, and impaired autoregulation of cerebral blood flow, were quantified and correlated with histology. Additionally, longitudinal microscopy revealed remodeling and flow recovery after one week of chronic stroke. Intrinsic scattering properties serve as reporters of acute cellular and vascular injury and recovery in experimental stroke. Multi-parametric OCT represents a robust in vivo imaging platform to comprehensively investigate these properties.

  11. Long-range synchrony in the gamma band: role in music perception.

    PubMed

    Bhattacharya, J; Petsche, H; Pereda, E

    2001-08-15

    Synchronization seems to be a central mechanism for neuronal information processing within and between multiple brain areas. Furthermore, synchronization in the gamma band has been shown to play an important role in higher cognitive functions, especially by binding the necessary spatial and temporal information in different cortical areas to build a coherent perception. Specific task-induced (evoked) gamma oscillations have often been taken as an indication of synchrony, but the presence of long-range synchrony cannot be inferred from spectral power in the gamma range. We studied the usefulness of a relatively new measure, called similarity index to detect asymmetric interdependency between two brain regions. Spontaneous EEG from two groups-musicians and non-musicians-were recorded during several states: listening to music, listening to text, and at rest (eyes closed and eyes open). While listening to music, degrees of the gamma band synchrony over distributed cortical areas were found to be significantly higher in musicians than non-musicians. Yet no differences between these two groups were found at resting conditions and while listening to a neutral text. In contrast to the degree of long-range synchrony, spectral power in the gamma band was higher in non-musicians. The degree of spatial synchrony, a measure of signal complexity based on eigen-decomposition method, was also significantly increased in musicians while listening to music. As compared with non-musicians, the finding of increased long-range synchrony in musicians independent of spectral power is interpreted as a manifestation of a more advanced musical memory of musicians in binding together several features of the intrinsic complexity of music in a dynamical way.

  12. Directional couplers based on long-range air-hole assisted subwavelength waveguides

    NASA Astrophysics Data System (ADS)

    Zhou, Weikang; Liang, Xiao; Lin, Canbin; Liu, Lintao; Tao, Jin; Huang, Xu Guang

    2017-10-01

    In this paper, we propose X-type and K-type couplers based on the novel long-range air-hole assisted subwavelength waveguides. A finite-difference time-domain (FDTD) method is used to simulate and analyze their characteristics. The results reveal that both the X-type and K-type couplers have very small transverse widths, which is suitable for high-density photonic integration. The excess losses of two couplers are less than 0.25 dB in one coupling period. Also, they can be integrated with other long-range air-hole assisted subwavelength waveguide devices to constitute large-scale planar integrated functional systems, which cannot be achieved by other waveguide couplers.

  13. Long-range transport and universality classes in in vitro viral infection spread

    NASA Astrophysics Data System (ADS)

    Manrubia, S. C.; García-Arriaza, J.; Domingo, E.; Escarmís, C.

    2006-05-01

    Dispersal mechanisms play a main role in the dynamics of infection spread. Recent experimental results with in vitro infections of foot-and-mouth disease virus reveal that the time needed for the virus to kill a cellular monolayer depends qualitatively on the number of viral particles required to initiate infection in a susceptible cell. A two-dimensional susceptible-infected-removed (SIR) model based on the experimental setting agrees with the observations only when viral particles are subject to long-range transport. Numerical and analytical results show that this long-range transport plays a role when a single particle causes infection, while it is inefficient when complementation between two or more particles is necessary.

  14. 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.

  15. Fractal mechanisms and heart rate dynamics. Long-range correlations and their breakdown with disease

    NASA Technical Reports Server (NTRS)

    Peng, C. K.; Havlin, S.; Hausdorff, J. M.; Mietus, J. E.; Stanley, H. E.; Goldberger, A. L.

    1995-01-01

    Under healthy conditions, the normal cardiac (sinus) interbeat interval fluctuates in a complex manner. Quantitative analysis using techniques adapted from statistical physics reveals the presence of long-range power-law correlations extending over thousands of heartbeats. This scale-invariant (fractal) behavior suggests that the regulatory system generating these fluctuations is operating far from equilibrium. In contrast, it is found that for subjects at high risk of sudden death (e.g., congestive heart failure patients), these long-range correlations break down. Application of fractal scaling analysis and related techniques provides new approaches to assessing cardiac risk and forecasting sudden cardiac death, as well as motivating development of novel physiologic models of systems that appear to be heterodynamic rather than homeostatic.

  16. Fractal mechanisms and heart rate dynamics. Long-range correlations and their breakdown with disease

    NASA Technical Reports Server (NTRS)

    Peng, C. K.; Havlin, S.; Hausdorff, J. M.; Mietus, J. E.; Stanley, H. E.; Goldberger, A. L.

    1995-01-01

    Under healthy conditions, the normal cardiac (sinus) interbeat interval fluctuates in a complex manner. Quantitative analysis using techniques adapted from statistical physics reveals the presence of long-range power-law correlations extending over thousands of heartbeats. This scale-invariant (fractal) behavior suggests that the regulatory system generating these fluctuations is operating far from equilibrium. In contrast, it is found that for subjects at high risk of sudden death (e.g., congestive heart failure patients), these long-range correlations break down. Application of fractal scaling analysis and related techniques provides new approaches to assessing cardiac risk and forecasting sudden cardiac death, as well as motivating development of novel physiologic models of systems that appear to be heterodynamic rather than homeostatic.

  17. Investigation of long-range temporal correlation in electron cyclotron resonance produced linear magnetized plasma of the MaPLE device

    NASA Astrophysics Data System (ADS)

    Biswas, Subir; Iyengar, A. N. S.; Pal, Rabindranath

    2012-03-01

    Long range temporal correlation of the low frequency fluctuations is investigated in a linear electron cyclotron resonance produced magnetized plasma at different radial positions and filling gas pressures. These fluctuations turn from chaotic to coherent and again chaotic as one moves radially outwards from the center towards the edge region. The power spectrum of these fluctuations shows three distinct frequency regions characterized by their power exponents. Long range temporal correlation of these fluctuations is investigated by estimating the self similarity parameter (Hurst exponents) using rescaled range (R/S) statistics as well as from power spectrum analysis. Dependence of this long range temporal correlation on filling gas pressure has also been investigated.

  18. Synchronization and plateau splitting of coupled oscillators with long-range power-law interactions

    NASA Astrophysics Data System (ADS)

    Kuo, Huan-Yu; Wu, Kuo-An

    2015-12-01

    We investigate synchronization and plateau splitting of coupled oscillators on a one-dimensional lattice with long-range interactions that decay over distance as a power law. We show that in the thermodynamic limit the dynamics of systems of coupled oscillators with power-law exponent α ≤1 is identical to that of the all-to-all coupling case. For α >1 , oscillatory behavior of the phase coherence appears as a result of single plateau splitting into multiple plateaus. A coarse-graining method is used to investigate the onset of plateau splitting. We analyze a simple oscillatory state formed by two plateaus in detail and propose a systematic approach to predict the onset of plateau splitting. The prediction of breaking points of plateau splitting is in quantitatively good agreement with numerical simulations.

  19. Long-range Cooper pair splitter with high entanglement production rate

    PubMed Central

    Chen, Wei; Shi, D. N.; Xing, D. Y.

    2015-01-01

    Cooper pairs in the superconductor are a natural source of spin entanglement. The existing proposals of the Cooper pair splitter can only realize a low efficiency of entanglement production, and its size is constrained by the superconducting coherence length. Here we show that a long-range Cooper pair splitter can be implemented in a normal metal-superconductor-normal metal (NSN) junction by driving a supercurrent in the S. The supercurrent results in a band gap modification of the S, which significantly enhances the crossed Andreev reflection (CAR) of the NSN junction and simultaneously quenches its elastic cotunneling. Therefore, a high entanglement production rate close to its saturation value can be achieved by the inverse CAR. Interestingly, in addition to the conventional entangled electron states between opposite energy levels, novel entangled states with equal energy can also be induced in our proposal. PMID:25556521

  20. In-flight sleep, pilot fatigue and Psychomotor Vigilance Task performance on ultra-long range versus long range flights.

    PubMed

    Gander, Philippa H; Signal, T Leigh; van den Berg, Margo J; Mulrine, Hannah M; Jay, Sarah M; Jim Mangie, Captain

    2013-12-01

    This study evaluated whether pilot fatigue was greater on ultra-long range (ULR) trips (flights >16 h on 10% of trips in a 90-day period) than on long range (LR) trips. The within-subjects design controlled for crew complement, pattern of in-flight breaks, flight direction and departure time. Thirty male Captains (mean age = 54.5 years) and 40 male First officers (mean age = 48.0 years) were monitored on commercial passenger flights (Boeing 777 aircraft). Sleep was monitored (actigraphy, duty/sleep diaries) from 3 days before the first study trip to 3 days after the second study trip. Karolinska Sleepiness Scale, Samn-Perelli fatigue ratings and a 5-min Psychomotor Vigilance Task were completed before, during and after every flight. Total sleep in the 24 h before outbound flights and before inbound flights after 2-day layovers was comparable for ULR and LR flights. All pilots slept on all flights. For each additional hour of flight time, they obtained an estimated additional 12.3 min of sleep. Estimated mean total sleep was longer on ULR flights (3 h 53 min) than LR flights (3 h 15 min; P(F) = 0.0004). Sleepiness ratings were lower and mean reaction speed was faster at the end of ULR flights. Findings suggest that additional in-flight sleep mitigated fatigue effectively on longer flights. Further research is needed to clarify the contributions to fatigue of in-flight sleep versus time awake at top of descent. The study design was limited to eastward outbound flights with two Captains and two First Officers. Caution must be exercised when extrapolating to different operations. © 2013 European Sleep Research Society.

  1. Long-range global population projections, as assessed in 1980.

    PubMed

    1982-01-01

    UN medium range projections prepared in the 1980 assessment projected the population of individual countries up to the year 2025. The long range projections discussed here were prepared by projecting the population of 8 major world regions from 2025-2100. The purpose of the projection was to observe the implications of the changes from the 1978 assessment made in the 1980 medium range projections on the long range projections of the world's populations. As in previous projections, high, medium, and low variants were prepared in which fertility is assumed to be constant at the replacement level but at different times in the future. In addition, these projections contain 2 variants not previously prepared--namely, the growth and decline variants, in which the ultimate net reproduction rate is 1.05 and 0.95, respectively. In all the variants, expectation of life at birth is assumed to reach 75 years for males and 80 for females. According to the current medium variant projection, the earth's population will become stationary after 2095 at 10.2 billion persons, compared with a total of 10.5 billion projected in the 1978 assessment. The lower projection is largely attributable to a recent decline in the growth rate of several countries in South Asia which was greater than previously assumed. When the world population becomes stationary, both crude birth and death rates would be about 13/1000. In the decline variant, total population would peak at 7.7 billion in 2055, then decline gradually to 7.2 billion in 2100. The total population as projected by the growth variant would equal 14.9 billion in 2100 and would still be growing slowly. Between 1980 and 2050, 95% of the world's growth will occur in the currently less developed regions. Their share of total population will increase from 75-85% during that period. The age structure in all regions is expected to converge to 1 in which the median age is 39 years, the proportion both below age 15 and above age 64 is about 19

  2. NIRS-Based Hyperscanning Reveals Increased Interpersonal Coherence in Superior Frontal Cortex during Cooperation

    PubMed Central

    Cui, Xu; Bryant, Daniel M.; Reiss, Allan L.

    2011-01-01

    We used Near-Infrared Spectroscopy (NIRS) to simultaneously measure brain activity in two people while they played a computer-based cooperation game side by side. Inter-brain activity coherence was calculated between the two participants. We found that the coherence between signals generated by participants right superior frontal cortices increased during cooperation, but not during competition. Increased coherence was also associated with better cooperation performance. To our knowledge, this work represents the first use of a single NIRS instrument for simultaneous measurements of brain activity in two people. This study demonstrates the use of NIRS-based hyperscanning in studies of social interaction in a naturalistic environment. PMID:21933717

  3. Long-range magnetic coupling across a polar insulating layer.

    PubMed

    Lü, W M; Saha, Surajit; Wang, X Renshaw; Liu, Z Q; Gopinadhan, K; Annadi, A; Zeng, S W; Huang, Z; Bao, B C; Cong, C X; Venkatesan, M; Yu, T; Coey, J M D; Ariando; Venkatesan, T

    2016-03-16

    Magnetic interactions in solids are normally mediated by short-range exchange or weak dipole fields. Here we report a magnetic interaction that can propagate over long distances (∼10 nm) across a polar insulating oxide spacer. Evidence includes oscillations of magnetization, coercivity and field-cooled loop shift with the thickness of LaAlO3 in La0.67Sr0.33MnO3/LaAlO3/SrTiO3 heterostructures. Similar modifications of the hysteresis loop appear when two coupled films of La0.67Sr0.33MnO3 are separated by LaAlO3, or another polar insulator, but they are absent when the oxide spacer layer is nonpolar. The loop shift is attributed to strong spin-orbit coupling and Dzyaloshinskii-Moriya interaction at the interfaces. There is evidence from inelastic light scattering that the polar spacer mediates long-range transmission of orbital magnetization. This coupling mechanism is expected to apply for any conducting ferromagnetic oxide with mixed valence; in view of electron hopping frequency involved, it raises the prospect of terahertz tunability of magnetic coupling.

  4. Long-range electron transfer in a model for DNA

    NASA Astrophysics Data System (ADS)

    Endres, R. G.; Cox, D. L.

    2001-03-01

    Long-range electron transfer (ET) between well separated donor (D) and acceptor (A) sites through quantum mechanical tunneling is essential to many biological processes like respiration, photosynthesis and possibly DNA repair and damage. We are investigating the distance dependence of the electronic transition matrix element H_DA and hence of the electron transfer rate in a model for DNA. Fluorescence quenching in DNA at D-A distances of 40 Åand more suggests ET with an unusually high decay length β-1 of order 10 Å (S.O.Kelley and J.K.Barton, in:Metal Ions in Biological Systems), A.Sigel and H.Sigel, Eds., Marcel Dekker, New York, Vol.36, 1999. Assuming strong electron interactions on the D complex and suitable energetics, this could be explained by formation of a many electron Kondo boundstate. We obtain H_DA from the splitting between the two lowest adiabatic electronic eigenenergies, which constitute the potential energy surfaces (PES) of the nuclear motion in lowest order Born-Oppenheimer approximation. The PES are constructed by coupling D and A to local breathing modes and by making a semi-analytical variational ansatz for the adiabatic eigenstates. The results from the PES are compared with results from the Mulliken-Hush algorithm.

  5. Ultracold Long-Range Rydberg Molecules with Complex Multichannel Spectra

    NASA Astrophysics Data System (ADS)

    Eiles, Matthew; Greene, Chris

    2016-05-01

    A generalized class of exotic long-range Rydberg molecules consisting of a multichannel Rydberg atom bound to a distant ground state atom by the Rydberg electron is predicted. These molecules are characterized by the rich physics provided by the strongly perturbed multichannel Rydberg spectra of divalent atoms, in contrast to the regular Rydberg series of the alkali atoms used to form Rydberg molecules to date. These multichannel Rydberg molecules exhibit favorable properties for laser excitation, because states exist where the quantum defect varies strongly with the principal quantum number n. In particular, the nd Rydberg state of calcium becomes nearly degenerate with states of high orbital angular momentum over the range 17 < n < 22 , promoting its admixture into the high l deeply bound ``trilobite'' molecule states and thereby circumventing the usual difficulty posed by electric dipole selection rules. Further novel molecular states are predicted to occur in the low- J states of silicon, which are strongly perturbed due to channel interactions between Rydberg series leading to the spin-orbit split ionization thresholds. These interactions manifest themselves in potential curves exhibiting two distinct length scales, providing novel opportunities for quantum manipulation. Supported in part by the National Science Foundation under Grant No. PHY-1306905.

  6. Long-range interacting systems in the unconstrained ensemble.

    PubMed

    Latella, Ivan; Pérez-Madrid, Agustín; Campa, Alessandro; Casetti, Lapo; Ruffo, Stefano

    2017-01-01

    Completely open systems can exchange heat, work, and matter with the environment. While energy, volume, and number of particles fluctuate under completely open conditions, the equilibrium states of the system, if they exist, can be specified using the temperature, pressure, and chemical potential as control parameters. The unconstrained ensemble is the statistical ensemble describing completely open systems and the replica energy is the appropriate free energy for these control parameters from which the thermodynamics must be derived. It turns out that macroscopic systems with short-range interactions cannot attain equilibrium configurations in the unconstrained ensemble, since temperature, pressure, and chemical potential cannot be taken as a set of independent variables in this case. In contrast, we show that systems with long-range interactions can reach states of thermodynamic equilibrium in the unconstrained ensemble. To illustrate this fact, we consider a modification of the Thirring model and compare the unconstrained ensemble with the canonical and grand-canonical ones: The more the ensemble is constrained by fixing the volume or number of particles, the larger the space of parameters defining the equilibrium configurations.

  7. Long-range interaction between heterogeneously charged membranes.

    PubMed

    Jho, Y S; Brewster, R; Safran, S A; Pincus, P A

    2011-04-19

    Despite their neutrality, surfaces or membranes with equal amounts of positive and negative charge can exhibit long-range electrostatic interactions if the surface charge is heterogeneous; this can happen when the surface charges form finite-size domain structures. These domains can be formed in lipid membranes where the balance of the different ranges of strong but short-ranged hydrophobic interactions and longer-ranged electrostatic repulsion result in a finite, stable domain size. If the domain size is large enough, oppositely charged domains in two opposing surfaces or membranes can be strongly correlated by the electrostatic interactions; these correlations give rise to an attractive interaction of the two membranes or surfaces over separations on the order of the domain size. We use numerical simulations to demonstrate the existence of strong attractions at separations of tens of nanometers. Large line tensions result in larger domains but also increase the charge density within the domain. This promotes correlations and, as a result, increases the intermembrane attraction. On the other hand, increasing the salt concentration increases both the domain size and degree of domain anticorrelation, but the interactions are ultimately reduced due to increased screening. The result is a decrease in the net attraction as salt concentration is increased. © 2011 American Chemical Society

  8. Long-Range Architecture in a Viral RNA Genome

    PubMed Central

    Archer, Eva J.; Simpson, Mark A.; Watts, Nicholas J.; O’Kane, Rory; Wang, Bangchen; Erie, Dorothy A.; McPherson, Alex; Weeks, Kevin M.

    2013-01-01

    We have developed a model for the secondary structure of the 1058-nucleotide plus-strand RNA genome of the icosahedral satellite tobacco mosaic virus (STMV) using nucleotide-resolution SHAPE chemical probing of the viral RNA isolated from virions and within the virion, perturbation of interactions distant in the primary sequence, and atomic force microscopy. These data are consistent with long-range base pairing interactions and a three-domain genome architecture. The compact domains of the STMV RNA have dimensions of 10 to 45 nm. Each of the three domains corresponds to a specific functional component of the virus: The central domain corresponds to the coding sequence of the single (capsid) protein encoded by the virus, whereas the 5′ and 3′ untranslated domains span signals essential for translation and replication, respectively. This three-domain architecture is compatible with interactions between the capsid protein and short RNA helices previously visualized by crystallography. STMV is among the simplest of the icosahedral viruses but, nonetheless, has an RNA genome with a complex higher-order structure that likely reflects high information content and an evolutionary relationship between RNA domain structure and essential replicative functions. PMID:23614526

  9. Record length requirement of long-range dependent teletraffic

    NASA Astrophysics Data System (ADS)

    Li, Ming

    2017-04-01

    This article contributes the highlights mainly in two folds. On the one hand, it presents a formula to compute the upper bound of the variance of the correlation periodogram measurement of teletraffic (traffic for short) with long-range dependence (LRD) for a given record length T and a given value of the Hurst parameter H (Theorems 1 and 2). On the other hand, it proposes two formulas for the computation of the variance upper bound of the correlation periodogram measurement of traffic of fractional Gaussian noise (fGn) type and the generalized Cauchy (GC) type, respectively (Corollaries 1 and 2). They may constitute a reference guideline of record length requirement of traffic with LRD. In addition, record length requirement for the correlation periodogram measurement of traffic with either the Schuster type or the Bartlett one is studied and the present results about it show that both types of periodograms may be used for the correlation measurement of traffic with a pre-desired variance bound of correlation estimation. Moreover, real traffic in the Internet Archive by the Special Interest Group on Data Communication under the Association for Computing Machinery of US (ACM SIGCOMM) is analyzed in the case study in this topic.

  10. Assessing long-range transport potential of persistent organic pollutants

    SciTech Connect

    Beyer, A.; Mackay, D.; Matthies, M.; Wania, F.; Webster, E.

    2000-02-15

    An analysis is presented of the factors controlling the potential for the long-range transport (LRT) of persistent organic pollutants subject to degrading reactions and reversible transport to other environmental media. The approach adopted generalizes those developed previously by van Pul et al. and Bennett et al. to estimate a characteristic travel distance (CTD) or a half-distance (analogous to a half-life) for a substance present in a mobile medium such as air and subject to reversible transport to other media such as soil and water. For substances discharged to immobile media, such as pesticides to soil, an effective travel distance (ETD) is defined as the distance that, for example, 1% of the discharged chemical may be transported. It is shown that existing multimedia box models can be used to estimate CTD and that a simple relationship exists between CTD and overall environmental persistence, which can be displayed graphically. CTDs in air and water are calculated illustratively for 18 chemicals, and recommendations are made regarding ranking or grouping chemicals according to their potential for LRT.

  11. Confirmation of NLDN Long Range Strike Locations with LIS Observations

    NASA Technical Reports Server (NTRS)

    Boeck, William; Boccippio, Dennis; Goodman, Steve; Cummins, Kenneth; Cramer, John; Goodman, H. Michael (Technical Monitor)

    2000-01-01

    This study compares the lightning locations reported by the National Lightning Detection Network (NLDN) with the lightning locations determined by the Lightning Imaging Sensor (LIS). The NLDN system identifies the rf signature of cloud-to-ground lightning. The LIS data is the top level of a hierarchy of optical data objects. The centroid and timing of each LIS lightning activity center are compared with each flash in a subset of the NLDN long range lightning location data in a portion of the Atlantic Ocean and the Caribbean Sea consisting of those locations more than 625 km from any sensor. This subset is produced by analyzing each reported NLDN location to determine if that location is within the LIS field of view at the time of the reported flash. The Tropical Rainfall Measuring Mission Satellite (TRMM) orbit limits the cross-sensor comparison to tropical and sub-tropical regions. Because the rf-detection system depends on ionospheric propagation conditions, a separate analysis was made for daylight conditions at both source and sensor as well as nighttime at both places. A full year of data is compared to provide an adequate sample of each data set. Confirmation of lightning in the general location of the NLDN report is established when LIS detected one or more centers of lightning activity within a 2 degree radius from the NLDN location.

  12. Stochastic Kinetic Monte Carlo algorithms for long-range Hamiltonians

    SciTech Connect

    Mason, D R; Rudd, R E; Sutton, A P

    2003-10-13

    We present a higher order kinetic Monte Carlo methodology suitable to model the evolution of systems in which the transition rates are non- trivial to calculate or in which Monte Carlo moves are likely to be non- productive flicker events. The second order residence time algorithm first introduced by Athenes et al.[1] is rederived from the n-fold way algorithm of Bortz et al.[2] as a fully stochastic algorithm. The second order algorithm can be dynamically called when necessary to eliminate unproductive flickering between a metastable state and its neighbors. An algorithm combining elements of the first order and second order methods is shown to be more efficient, in terms of the number of rate calculations, than the first order or second order methods alone while remaining statistically identical. This efficiency is of prime importance when dealing with computationally expensive rate functions such as those arising from long- range Hamiltonians. Our algorithm has been developed for use when considering simulations of vacancy diffusion under the influence of elastic stress fields. We demonstrate the improved efficiency of the method over that of the n-fold way in simulations of vacancy diffusion in alloys. Our algorithm is seen to be an order of magnitude more efficient than the n-fold way in these simulations. We show that when magnesium is added to an Al-2at.%Cu alloy, this has the effect of trapping vacancies. When trapping occurs, we see that our algorithm performs thousands of events for each rate calculation performed.

  13. Directed long-range molecular migration energized by surface reaction

    NASA Astrophysics Data System (ADS)

    Harikumar, K. R.; Polanyi, John C.; Zabet-Khosousi, Amir; Czekala, Piotr; Lin, Haiping; Hofer, Werner A.

    2011-05-01

    The recoil of adsorbates away (desorption) and towards (reaction) surfaces is well known. Here, we describe the long-range recoil of adsorbates in the plane of a surface, and accordingly the novel phenomenon of reactions occurring at a substantial distance from the originating event. Three thermal and three electron-induced surface reactions are shown by scanning tunnelling microscopy to propel their physisorbed ethylenic products across the rough surface of Si(100) over a distance of up to 200 Å before an attachment reaction. The recoil energy in the ethylenic products comes from thermal exoergicity or from electronic excitation of chemisorbed alkenes. We propose that the mechanism of migration is a rolling motion, because the recoiling molecule overcomes raised surface obstacles. Electronic excitation of propene causes directional recoil and often end-to-end inversion, suggesting cartwheeling. Ab initio calculations of the halogenation and electron-induced reactions support a model in which asymmetric forces between the molecule and the surface induce rotation and therefore migration.

  14. Long-range magnetic coupling across a polar insulating layer

    PubMed Central

    Lü, W. M.; Saha, Surajit; Wang, X. Renshaw; Liu, Z. Q.; Gopinadhan, K.; Annadi, A.; Zeng, S. W.; Huang, Z.; Bao, B. C.; Cong, C. X.; Venkatesan, M.; Yu, T.; Coey, J. M. D.; Ariando; Venkatesan, T.

    2016-01-01

    Magnetic interactions in solids are normally mediated by short-range exchange or weak dipole fields. Here we report a magnetic interaction that can propagate over long distances (∼10 nm) across a polar insulating oxide spacer. Evidence includes oscillations of magnetization, coercivity and field-cooled loop shift with the thickness of LaAlO3 in La0.67Sr0.33MnO3/LaAlO3/SrTiO3 heterostructures. Similar modifications of the hysteresis loop appear when two coupled films of La0.67Sr0.33MnO3 are separated by LaAlO3, or another polar insulator, but they are absent when the oxide spacer layer is nonpolar. The loop shift is attributed to strong spin–orbit coupling and Dzyaloshinskii–Moriya interaction at the interfaces. There is evidence from inelastic light scattering that the polar spacer mediates long-range transmission of orbital magnetization. This coupling mechanism is expected to apply for any conducting ferromagnetic oxide with mixed valence; in view of electron hopping frequency involved, it raises the prospect of terahertz tunability of magnetic coupling. PMID:26980456

  15. Long-Range Reconnaissance Imager on New Horizons

    NASA Astrophysics Data System (ADS)

    Cheng, A. F.; Weaver, H. A.; Conard, S. J.; Morgan, M. F.; Barnouin-Jha, O.; Boldt, J. D.; Cooper, K. A.; Darlington, E. H.; Grey, M. P.; Hayes, J. R.; Kosakowski, K. E.; Magee, T.; Rossano, E.; Sampath, D.; Schlemm, C.; Taylor, H. W.

    2008-10-01

    The LOng-Range Reconnaissance Imager (LORRI) is the high-resolution imaging instrument for the New Horizons mission to Pluto, its giant satellite Charon, its small moons Nix and Hydra, and the Kuiper Belt, which is the vast region of icy bodies extending roughly from Neptune’s orbit out to 50 astronomical units (AU). New Horizons launched on January 19, 2006, as the inaugural mission in NASA’s New Frontiers program. LORRI is a narrow-angle (field of view=0.29°), high-resolution (4.95 μrad pixels), Ritchey-Chrétien telescope with a 20.8-cm diameter primary mirror, a focal length of 263 cm, and a three-lens, field-flattening assembly. A 1,024×1,024 pixel (optically active region), thinned, backside-illuminated charge-coupled device (CCD) detector is used in the focal plane unit and is operated in frame-transfer mode. LORRI provides panchromatic imaging over a bandpass that extends approximately from 350 nm to 850 nm. LORRI operates in an extreme thermal environment, situated inside the warm spacecraft with a large, open aperture viewing cold space. LORRI has a silicon carbide optical system, designed to maintain focus over the operating temperature range without a focus adjustment mechanism. Moreover, the spacecraft is thruster-stabilized without reaction wheels, placing stringent limits on the available exposure time and the optical throughput needed to satisfy the measurement requirements.

  16. Long-range epidemic spreading in a random environment

    NASA Astrophysics Data System (ADS)

    Juhász, Róbert; Kovács, István A.; Iglói, Ferenc

    2015-03-01

    Modeling long-range epidemic spreading in a random environment, we consider a quenched, disordered, d -dimensional contact process with infection rates decaying with distance as 1 /rd +σ . We study the dynamical behavior of the model at and below the epidemic threshold by a variant of the strong-disorder renormalization-group method and by Monte Carlo simulations in one and two spatial dimensions. Starting from a single infected site, the average survival probability is found to decay as P (t ) ˜t-d /z up to multiplicative logarithmic corrections. Below the epidemic threshold, a Griffiths phase emerges, where the dynamical exponent z varies continuously with the control parameter and tends to zc=d +σ as the threshold is approached. At the threshold, the spatial extension of the infected cluster (in surviving trials) is found to grow as R (t ) ˜t1 /zc with a multiplicative logarithmic correction and the average number of infected sites in surviving trials is found to increase as Ns(t ) ˜(lnt) χ with χ =2 in one dimension.

  17. Long-range epidemic spreading in a random environment.

    PubMed

    Juhász, Róbert; Kovács, István A; Iglói, Ferenc

    2015-03-01

    Modeling long-range epidemic spreading in a random environment, we consider a quenched, disordered, d-dimensional contact process with infection rates decaying with distance as 1/rd+σ. We study the dynamical behavior of the model at and below the epidemic threshold by a variant of the strong-disorder renormalization-group method and by Monte Carlo simulations in one and two spatial dimensions. Starting from a single infected site, the average survival probability is found to decay as P(t)∼t-d/z up to multiplicative logarithmic corrections. Below the epidemic threshold, a Griffiths phase emerges, where the dynamical exponent z varies continuously with the control parameter and tends to zc=d+σ as the threshold is approached. At the threshold, the spatial extension of the infected cluster (in surviving trials) is found to grow as R(t)∼t1/zc with a multiplicative logarithmic correction and the average number of infected sites in surviving trials is found to increase as Ns(t)∼(lnt)χ with χ=2 in one dimension.

  18. Long-range interactions between rubidium and potassium Rydberg atoms

    NASA Astrophysics Data System (ADS)

    Samboy, Nolan

    2017-03-01

    We investigate the long-range, two-body interactions between rubidium and potassium atoms in highly excited (n =70 ) Rydberg states. After establishing properly symmetrized asymptotic basis states, we diagonalize an interaction Hamiltonian consisting of the standard Coulombic potential expansion and atomic fine structure to calculate electronic potential energy curves. We find that when both atoms are excited to either the 70 s state or the 70 p state, both the Ω =0+ symmetry interactions and the Ω =0- symmetry interactions demonstrate a deep potential well capable of supporting many bound levels; the sizes of the corresponding dimer states are of the order of 2.25 μ m . We establish n -scaling relations for the equilibrium separation Re and the dissociation energy De and find these relations to be consistent with similar calculations involving the homonuclear interactions between rubidium and cesium. We discuss the specific effects of ℓ mixing and the exact composition of the calculated potential well via the expansion coefficients of the asymptotic basis states. Finally, we apply a Landau-Zener treatment to show that the dimer states are stable with respect to predissociation.

  19. Long-range spin Seebeck effect and acoustic spin pumping.

    PubMed

    Uchida, K; Adachi, H; An, T; Ota, T; Toda, M; Hillebrands, B; Maekawa, S; Saitoh, E

    2011-10-01

    Imagine that a metallic wire is attached to a part of a large insulator, which itself exhibits no magnetization. It seems impossible for electrons in the wire to register where the wire is positioned on the insulator. Here we found that, using a Ni₈₁Fe₁₉/Pt bilayer wire on an insulating sapphire plate, electrons in the wire recognize their position on the sapphire. Under a temperature gradient in the sapphire, surprisingly, the voltage generated in the Pt layer is shown to reflect the wire position, although the wire is isolated both electrically and magnetically. This non-local voltage is due to the coupling of spins and phonons: the only possible carrier of information in this system. We demonstrate this coupling by directly injecting sound waves, which realizes the acoustic spin pumping. Our finding provides a persuasive answer to the long-range nature of the spin Seebeck effect, and it opens the door to 'acoustic spintronics' in which sound waves are exploited for constructing spin-based devices.

  20. Long-range interactions between DNA-bound ligands.

    PubMed

    Samuelson, P; Jansen, K; Kubista, M

    1994-09-01

    We have studied the interaction of the A:T specific minor-groove binding ligand 4',6-diamidino-2-phenylindole (DAPI) with synthetic DNA oligomers containing specific binding sites in order to investigate possible long-range interactions between bound ligands. We find that DAPI binds cooperatively to the oligomers. The degree of cooperativity increases with increasing number of binding sites and decreases with the separation between them. This dependence is paralleled by changes in the induced circular dichroism spectrum of DAPI, which decreases in intensity at 335 nm and increases at 365 nm. These results are consistent with an allosteric interaction of DAPI with DNA, where bound ligands cooperatively alter the structure of the DNA molecule. This structural change seems possible to induce under various conditions, including physiological. One consequence of allosteric binding is that ligands bound at a distance from each other sense each other's presence and influence each others' properties. If some regulatory proteins induce the same conformational change as DAPI, novel mechanisms for controlling gene expression can be anticipated.

  1. Entropy production in systems with long range interactions

    NASA Astrophysics Data System (ADS)

    Pakter, Renato; Levin, Yan

    2017-04-01

    On a fine grained scale the Gibbs entropy of an isolated system remains constant throughout its dynamical evolution. This is a consequence of Liouville’s theorem for Hamiltonian systems and appears to contradict the second law of thermodynamics. In reality, however, there is no problem since the thermodynamic entropy should be associated with the Boltzmann entropy, which for non-equilibrium systems is different from Gibbs entropy. The Boltzmann entropy accounts for the microstates which are not accessible from a given initial condition, but are compatible with a given macrostate. In a sense the Boltzmann entropy is a coarse grained version of the Gibbs entropy and will not decrease during the dynamical evolution of a macroscopic system. In this paper we will explore the entropy production for systems with long range interactions. Unlike for short range systems, in the thermodynamic limit, the probability density function for these systems decouples into a product of one particle distribution functions and the coarse grained entropy can be calculated explicitly. We find that the characteristic time for the entropy production scales with the number of particles as {{N}α} , with α >0 , so that in the thermodynamic limit entropy production takes an infinite amount of time.

  2. Functional Sites Induce Long-Range Evolutionary Constraints in Enzymes

    PubMed Central

    Jack, Benjamin R.; Meyer, Austin G.; Echave, Julian; Wilke, Claus O.

    2016-01-01

    Functional residues in proteins tend to be highly conserved over evolutionary time. However, to what extent functional sites impose evolutionary constraints on nearby or even more distant residues is not known. Here, we report pervasive conservation gradients toward catalytic residues in a dataset of 524 distinct enzymes: evolutionary conservation decreases approximately linearly with increasing distance to the nearest catalytic residue in the protein structure. This trend encompasses, on average, 80% of the residues in any enzyme, and it is independent of known structural constraints on protein evolution such as residue packing or solvent accessibility. Further, the trend exists in both monomeric and multimeric enzymes and irrespective of enzyme size and/or location of the active site in the enzyme structure. By contrast, sites in protein–protein interfaces, unlike catalytic residues, are only weakly conserved and induce only minor rate gradients. In aggregate, these observations show that functional sites, and in particular catalytic residues, induce long-range evolutionary constraints in enzymes. PMID:27138088

  3. On long-range forces of repulsion between biological cells

    NASA Astrophysics Data System (ADS)

    Derjaguin, B. V.; Golovanov, M. V.

    1992-05-01

    We have established experimentally that when biological cells, for example, blood, are suspended in concentrated solutions of inorganic electrolytes (for instance, in a 15% solution of sodium chloride) then around some cells (leucocytes, especially tumour cells) there form haloes, i.e., circular spaces free from background cells (erythrocytes, yeast cells, colloidal particles of Indian ink). In the medium made up of erythrocytes the haloes form during 5-10 min as a result of the background cells drawing apart from the central halo-forming cell (HFC) at a distance of 10-100 μm and more. In the medium made of the Indian ink particles, the haloes form during 2-4 s and attain a thickness of about 10-20 μm. The erythrocytes and the haloes forming in their medium can be preserved for about three to five days at room temperature. It has been established that, when tumour HFCs are present at sufficient concentrations, they form hexagonal periodic structures having a mean spacing between cells of up to 60 μm. The authors put forward as one probable suggestion that the formation of haloes is largely determined by long-range repulsive forces arising from the phenomenon of diffusiophoresis generated by the diffusion currents that emerge from the surface of halo-forming cells.

  4. Lifetimes of ultra-long-range strontium Rydberg molecules

    NASA Astrophysics Data System (ADS)

    Camargo, F.; Whalen, J. Â. D.; Ding, R.; Sadeghpour, H. R.; Yoshida, S.; Burgdörfer, J.; Dunning, F. B.; Killian, T. C.

    2016-02-01

    The lifetimes of the lower-lying vibrational states of ultra-long-range strontium Rydberg molecules comprising one ground-state 5 s2 1S0 atom and one Rydberg atom in the 5 s 38 s 3S1 state are reported. The molecules are created in an ultracold gas held in an optical dipole trap and their numbers determined using field ionization, the product electrons being detected by a microchannel plate. The measurements show that, in marked contrast to earlier measurements involving rubidium Rydberg molecules, the lifetimes of the low-lying molecular vibrational states are very similar to those of the parent Rydberg atoms. This results because the strong p -wave resonance in low-energy electron-rubidium scattering, which strongly influences the rubidium molecular lifetimes, is not present for strontium. The absence of this resonance offers advantages for experiments involving strontium Rydberg atoms as impurities in quantum gases and for testing of theories of molecular formation and decay.

  5. Long range attraction between two different likely charged macroions

    NASA Astrophysics Data System (ADS)

    Shklovskii, B. I.

    2005-03-01

    It is known that in a water solution two likely charged macroions can attract each other due to correlations of multivalent counterions adsorbed on their surfaces [1]. This attraction is short-ranged and decays exponentially with distance between macroions. In this work, we show that a longer range attraction exists when the bare surface charge densities of the two macroions have the same sign but different in absolute values. The key idea is that with adsorbed multivalent counterions, two such macroions can be considered as conductors with fixed but different electric potentials. Each potential is determined by the difference between the entropic bulk chemical potential of a multivalent counterion and its correlation chemical potential determined by the bare surface charge density of the macroion. When the two macroions are close enough, their adjacent spots form a charged capacitor, which leads to attraction. This attraction is long-ranged: it decays with distance as a power law. This attractive force may play a important role in gene delivery, in which poly-cations are used to invert the charge of negative DNA so that it is not repelled by negative charged cell membrane. The attraction discussed above makes sure that even the charge of the membrane is also inverted, DNA may still be attracted to it. [1] I. Rouzina and V. A. Bloomfield, J. Phys. Chem. 100, 9977 (1996).

  6. Long-range interacting systems in the unconstrained ensemble

    NASA Astrophysics Data System (ADS)

    Latella, Ivan; Pérez-Madrid, Agustín; Campa, Alessandro; Casetti, Lapo; Ruffo, Stefano

    2017-01-01

    Completely open systems can exchange heat, work, and matter with the environment. While energy, volume, and number of particles fluctuate under completely open conditions, the equilibrium states of the system, if they exist, can be specified using the temperature, pressure, and chemical potential as control parameters. The unconstrained ensemble is the statistical ensemble describing completely open systems and the replica energy is the appropriate free energy for these control parameters from which the thermodynamics must be derived. It turns out that macroscopic systems with short-range interactions cannot attain equilibrium configurations in the unconstrained ensemble, since temperature, pressure, and chemical potential cannot be taken as a set of independent variables in this case. In contrast, we show that systems with long-range interactions can reach states of thermodynamic equilibrium in the unconstrained ensemble. To illustrate this fact, we consider a modification of the Thirring model and compare the unconstrained ensemble with the canonical and grand-canonical ones: The more the ensemble is constrained by fixing the volume or number of particles, the larger the space of parameters defining the equilibrium configurations.

  7. ORNL long-range environmental and waste management plan

    SciTech Connect

    Baldwin, J.S.; Bates, L.D.; Brown, C.H.; Easterday, C.A.; Hill, L.G.; Kendrick, C.M.; McNeese, L.E.; Myrick, T.E.; Payne, T.L.; Pepper, C.E.; Robinson, S.M.; Rohwer, P.S.; Scanlan, T.F.; Smith, M.A.; Stratton, L.E.; Trabalka, J.R.

    1989-09-01

    This report, the ORNL Long-Range Environmental and Waste Management Plan, is the annual update in a series begun in fiscal year 1985. Its primary purpose is to provide a thorough and systematic planning document to reflect the continuing process of site assessment, strategy development, and planning for the current and long-term control of environmental issues, waste management practices, and remedial action requirements. The document also provides an estimate of the resources required to implement the current plan. This document is not intended to be a budget document; it is, however, intended to provide guidance to both Martin Marietta Energy Systems, Inc., and the US Department of Energy (DOE) management as to the near order of magnitude of the resources (primarily funding requirements) and the time frame required to execute the strategy in the present revision of the plan. As with any document of this nature, the near-term (one to three years) part of the plan is a pragmatic assessment of the current program and ongoing capital projects and reflects the efforts perceived to be necessary to comply with all current state and federal regulations and DOE orders. It also should be in general agreement with current budget (funding) requests and obligations for these immediate years. 55 figs., 72 tabs.

  8. Directed long-range molecular migration energized by surface reaction.

    PubMed

    Harikumar, K R; Polanyi, John C; Zabet-Khosousi, Amir; Czekala, Piotr; Lin, Haiping; Hofer, Werner A

    2011-05-01

    The recoil of adsorbates away (desorption) and towards (reaction) surfaces is well known. Here, we describe the long-range recoil of adsorbates in the plane of a surface, and accordingly the novel phenomenon of reactions occurring at a substantial distance from the originating event. Three thermal and three electron-induced surface reactions are shown by scanning tunnelling microscopy to propel their physisorbed ethylenic products across the rough surface of Si(100) over a distance of up to 200 Å before an attachment reaction. The recoil energy in the ethylenic products comes from thermal exoergicity or from electronic excitation of chemisorbed alkenes. We propose that the mechanism of migration is a rolling motion, because the recoiling molecule overcomes raised surface obstacles. Electronic excitation of propene causes directional recoil and often end-to-end inversion, suggesting cartwheeling. Ab initio calculations of the halogenation and electron-induced reactions support a model in which asymmetric forces between the molecule and the surface induce rotation and therefore migration.

  9. Impact of turbulence in long range quantum and classical communications.

    PubMed

    Capraro, Ivan; Tomaello, Andrea; Dall'Arche, Alberto; Gerlin, Francesca; Ursin, Ruper; Vallone, Giuseppe; Villoresi, Paolo

    2012-11-16

    The study of the free-space distribution of quantum correlations is necessary for any future application of quantum and classical communication aiming to connect two remote locations. Here we study the propagation of a coherent laser beam over 143 km (between Tenerife and La Palma Islands of the Canary archipelagos). By attenuating the beam we also studied the propagation at the single photon level. We investigated the statistic of arrival of the incoming photons and the scintillation of the beam. From the analysis of the data, we propose the exploitation of turbulence to improve the signal to noise ratio of the signal.

  10. 25 CFR 170.410 - What is the purpose of tribal long-range transportation planning?

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 25 Indians 1 2011-04-01 2011-04-01 false What is the purpose of tribal long-range transportation... Program Facilities Long-Range Transportation Planning § 170.410 What is the purpose of tribal long-range transportation planning? (a) The purpose of long-range transportation planning is to clearly demonstrate a...

  11. 25 CFR 170.410 - What is the purpose of tribal long-range transportation planning?

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 25 Indians 1 2013-04-01 2013-04-01 false What is the purpose of tribal long-range transportation... Program Facilities Long-Range Transportation Planning § 170.410 What is the purpose of tribal long-range transportation planning? (a) The purpose of long-range transportation planning is to clearly demonstrate a...

  12. 25 CFR 170.411 - What may a long-range transportation plan include?

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 25 Indians 1 2012-04-01 2011-04-01 true What may a long-range transportation plan include? 170.411... Long-Range Transportation Planning § 170.411 What may a long-range transportation plan include? A comprehensive long-range transportation plan may include: (a) An evaluation of a full range of...

  13. 25 CFR 170.410 - What is the purpose of tribal long-range transportation planning?

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 25 Indians 1 2012-04-01 2011-04-01 true What is the purpose of tribal long-range transportation... Program Facilities Long-Range Transportation Planning § 170.410 What is the purpose of tribal long-range transportation planning? (a) The purpose of long-range transportation planning is to clearly demonstrate a...

  14. 25 CFR 170.411 - What may a long-range transportation plan include?

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 25 Indians 1 2011-04-01 2011-04-01 false What may a long-range transportation plan include? 170... Long-Range Transportation Planning § 170.411 What may a long-range transportation plan include? A comprehensive long-range transportation plan may include: (a) An evaluation of a full range of...

  15. 25 CFR 170.411 - What may a long-range transportation plan include?

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 25 Indians 1 2013-04-01 2013-04-01 false What may a long-range transportation plan include? 170... Long-Range Transportation Planning § 170.411 What may a long-range transportation plan include? A comprehensive long-range transportation plan may include: (a) An evaluation of a full range of...

  16. Self-Consistent Density Functional Including Long-Range van der Waals Interactions

    NASA Astrophysics Data System (ADS)

    Ferri, Nicola; Distasio, Robert A., Jr.; Car, Roberto; Scheffler, Matthias; Tkatchenko, Alexandre

    2013-03-01

    Van der Waals (vdW) interactions are significant for a wide variety of systems, from noble-gas dimers to organic/inorganic interfaces. The long-range vdW energy is a tiny fraction (0.001%) of the total energy, hence it is typically assumed not to change electronic properties. Although the vdW-DF functional includes the effect of vdW energy on electronic structure, the influence of ``true'' long-range vdW interactions is difficult to assess since a significant part of vdW-DF energy arises from short distances. Here, we present a self-consistent (SC) implementation of the long-range Tkatchenko-Scheffler (TS) functional, including its extension to surfaces. The analysis of self-consistency for rare-gas dimers allows us to reconcile two different views on vdW interactions: (i) Feynman's view that claims changes in the electron density and (ii) atoms separated by infinite barrier. In agreement with previous work, we find negligible contribution from self-consistency in the structure and stability of vdW-bound complexes. However, a closer look at organic/inorganic interfaces reveals notable modification of energy levels when using the SC-TS vdW density functional.

  17. The ESCRT machinery regulates the secretion and long-range activity of Hedgehog.

    PubMed

    Matusek, Tamás; Wendler, Franz; Polès, Sophie; Pizette, Sandrine; D'Angelo, Gisela; Fürthauer, Maximilian; Thérond, Pascal P

    2014-12-04

    The conserved family of Hedgehog (Hh) proteins acts as short- and long-range secreted morphogens, controlling tissue patterning and differentiation during embryonic development. Mature Hh carries hydrophobic palmitic acid and cholesterol modifications essential for its extracellular spreading. Various extracellular transportation mechanisms for Hh have been suggested, but the pathways actually used for Hh secretion and transport in vivo remain unclear. Here we show that Hh secretion in Drosophila wing imaginal discs is dependent on the endosomal sorting complex required for transport (ESCRT). In vivo the reduction of ESCRT activity in cells producing Hh leads to a retention of Hh at the external cell surface. Furthermore, we show that ESCRT activity in Hh-producing cells is required for long-range signalling. We also provide evidence that pools of Hh and ESCRT proteins are secreted together into the extracellular space in vivo and can subsequently be detected together at the surface of receiving cells. These findings uncover a new function for ESCRT proteins in controlling morphogen activity and reveal a new mechanism for the transport of secreted Hh across the tissue by extracellular vesicles, which is necessary for long-range target induction.

  18. Long-range spatial correlations in the turbulent edge plasma of the L-2M stellarator

    SciTech Connect

    Vasil’kov, D. G. Kholnov, Yu. V.; Shchepetov, S. V.

    2013-08-15

    Long-range spatial correlations in the turbulent plasma of the L-2M stellarator were revealed experimentally, and their relation to the geometry of magnetic surfaces was analyzed (Plasma Phys. Control. Fusion 50, 045001 (2008)). The operation modes of the facility in which fast transport transitions in plasma are possible were studied. Upon these transitions, the turbulence level is found to decrease substantially. It is shown that long-range spatial correlations are typical of relatively narrow frequency ranges. In particular, before a transport transition, such frequency ranges are f ∼ 30–40 kHz and f ∼ 1–3 kHz. After the transition, long-range spatial correlations in the frequency range of f ∼ 30–40 kHz disappear due to a significant decrease in the turbulence level in this frequency range. At the same time, correlations in the low frequency range are retained and new correlations at frequencies of f ∼ 6-12 kHz occur. It is found that global electromagnetic oscillations in the frequency range of f ∼ 1–3 kHz are related to the m/n = 0/0 perturbation and its toroidal satellites (here, m and n are the poloidal and toroidal mode numbers, respectively). It is also shown that, after the transport transition, a three-dimensional localized electromagnetic mode at the frequency of the geodesic acoustic mode governed by the average magnetic field curvature is excited. At higher frequencies typical of a geodesic acoustic mode related to the three-dimensional curvature of the magnetic field, no long-range spatial correlations were observed both before and after the transport transition.

  19. Multi-scale variability and long-range memory in indoor Radon concentrations from Coimbra, Portugal

    NASA Astrophysics Data System (ADS)

    Donner, Reik V.; Potirakis, Stelios; Barbosa, Susana

    2014-05-01

    The presence or absence of long-range correlations in the variations of indoor Radon concentrations has recently attracted considerable interest. As a radioactive gas naturally emitted from the ground in certain geological settings, understanding environmental factors controlling Radon concentrations and their dynamics is important for estimating its effect on human health and the efficiency of possible measures for reducing the corresponding exposition. In this work, we re-analyze two high-resolution records of indoor Radon concentrations from Coimbra, Portugal, each of which spans several months of continuous measurements. In order to evaluate the presence of long-range correlations and fractal scaling, we utilize a multiplicity of complementary methods, including power spectral analysis, ARFIMA modeling, classical and multi-fractal detrended fluctuation analysis, and two different estimators of the signals' fractal dimensions. Power spectra and fluctuation functions reveal some complex behavior with qualitatively different properties on different time-scales: white noise in the high-frequency part, indications of some long-range correlated process dominating time scales of several hours to days, and pronounced low-frequency variability associated with tidal and/or meteorological forcing. In order to further decompose these different scales of variability, we apply two different approaches. On the one hand, applying multi-resolution analysis based on the discrete wavelet transform allows separately studying contributions on different time scales and characterize their specific correlation and scaling properties. On the other hand, singular system analysis (SSA) provides a reconstruction of the essential modes of variability. Specifically, by considering only the first leading SSA modes, we achieve an efficient de-noising of our environmental signals, highlighting the low-frequency variations together with some distinct scaling on sub-daily time-scales resembling

  20. Engineering Technology Division Long-Range Plan, 1991--1995

    SciTech Connect

    Not Available

    1995-01-01

    This Engineering Technology Division Long-Range Plan is a departure from planning processes of the past. About a year ago we decided to approach our strategic planning in a very different way. With this plan we complete the first phase of a comprehensive process that has involved most of the Division staff. Through a series of brainstorming''meetings, we have accumulated a wealth of ideas. By this process, we have been able to identify our perceived strengths and weaknesses and to propose very challenging goals for the future. Early on in our planning, we selected two distinct areas where we desire changes. First, we want to pursue program development in a much more structured and dynamic manner: deciding what we want to do, developing plans, and providing the resources to follow through. Second, we want to change the way that we do business by developing more effective ways to work together within the Division and with the important groups that we interact with throughout Energy Systems. These initiatives are reflected in the plan and in related actions that the Division is implementing. The ETD mission is to perform research, development, conceptual design, analysis, fabrication, testing, and system demonstration of technology essential for (1) nuclear reactor systems and related technologies (2) space and defense systems (3) advanced systems for energy conversion and utilization, and (4) water and waste management systems, and to foster a vigorous program of technology transfer using the best available techniques of technical infusion into the marketplace. In meeting this mission, the Division will institute a documented pollution prevention program, ensure that environmental impact statements are prepared for the supporting program, and adhere to all environmental safety and health requirements. 4 figs., 2 tabs.

  1. Device Applications of Long-Range Surface Plasmons

    NASA Astrophysics Data System (ADS)

    Richards, John David

    Device applications of surface plasmons have been the subject of much interest since the introduction of surface plasmon biosensors in the early 1980's. A less well known coupled surface plasmon mode, called the long range surface plasmon (LRSP), exhibits lower loss and larger electric field enhancement than the surface plasmon (SP) mode. As a result, the LRSP mode has the potential to produce devices with better performance than the corresponding SP devices. In this thesis, the use of the LRSP mode in sensor and light modulator applications is theoretically and experimentally investigated. LRSP sensors are compared with SP sensors, both theoretically and experimentally. LRSP sensors offer greater design flexibility than SP sensors. In SP sensors, only the metal film thickness can be varied, as compared to LRSP sensors, where the thickness of the metal film and a dielectric coupling gap can be varied. Theoretical calculations indicate that LRSP sensors are more sensitive to changes in interfacial permittivity, both bulk refractive index changes and refractive index changes caused by the formation of dielectric overlayers on the metal film. Experimental measurements are performed to verify that LRSP sensors provide higher sensitivity than SP sensors. A theoretical comparison of reflection-mode modulators for free space optical interconnects is performed. Fabry -Perot (FP), SP, and LRSP polymeric electro-optic modulators are considered. The reflectance and modulation characteristics of these devices are determined using a model that accounts for anisotropic layered media. The sensitivity of the reflectance and modulation characteristics to parameters such as the collimation of the optical beam, the choice of metal film, the operating wavelength, and the temperature of the polymeric film, is analyzed for these modulator structures. SP and FP polymeric electro-optic modulators have already been experimentally demonstrated. The experimental feasibility of a LRSP

  2. Long range laser propagation: power scaling and beam quality issues

    NASA Astrophysics Data System (ADS)

    Bohn, Willy L.

    2010-09-01

    This paper will address long range laser propagation applications where power and, in particular beam quality issues play a major role. Hereby the power level is defined by the specific mission under consideration. I restrict myself to the following application areas: (1)Remote sensing/Space based LIDAR, (2) Space debris removal (3)Energy transmission, and (4)Directed energy weapons Typical examples for space based LIDARs are the ADM Aeolus ESA mission using the ALADIN Nd:YAG laser with its third harmonic at 355 nm and the NASA 2 μm Tm:Ho:LuLiF convectively cooled solid state laser. Space debris removal has attracted more attention in the last years due to the dangerous accumulation of debris in orbit which become a threat to the satellites and the ISS space station. High power high brightness lasers may contribute to this problem by partially ablating the debris material and hence generating an impulse which will eventually de-orbit the debris with their subsequent disintegration in the lower atmosphere. Energy transmission via laser beam from space to earth has long been discussed as a novel long term approach to solve the energy problem on earth. In addition orbital transfer and stationkeeping are among the more mid-term applications of high power laser beams. Finally, directed energy weapons are becoming closer to reality as corresponding laser sources have matured due to recent efforts in the JHPSSL program. All of this can only be realized if he laser sources fulfill the necessary power requirements while keeping the beam quality as close as possible to the diffraction limited value. And this is the rationale and motivation of this paper.

  3. a Global Model for Long-Range Interaction `DAMPING Functions'

    NASA Astrophysics Data System (ADS)

    Myatt, Philip Thomas; McCourt, Frederick R. W.; Le Roy, Robert J.

    2016-06-01

    In recent years, `damping functions', which characterize the weakening of inverse-power-sum long-range interatomic interaction energies with increasing electron overlap, have become an increasing important component of models for diatomic molecule interaction potentials. However, a key feature of models for damping functions, their portability, has received little scrutiny. The present work set out to examine all available ab initio induction and dispersion damping function data and to attempt to devise a `global' scheme for diatomic molecule damping functions. It appears that while neutral (H, He, Li, and Ne, homonuclear and mixed) and anion (H^- with H, He and Li) species obey (approximately) one common rule, proton plus neutral (H^+ with H, He and Li) and non-proton-cation plus neutral systems (He^+ and Li^+ with H, He and Li), must each be treated separately. However, for all three cases, a version of the Douketis-Scoles-Thakkar (ionization potential)power factor is a key scaling parameter. R.J. Le Roy, C. C. Haugen, J. Tao and Hui Li, Mol. Phys. 109,435 (2011). P.J. Knowles and W.J. Meath,J. Mol. Phys. 60, 1143 (1987); R.J. Wheatley and W.J. Meath,J. Mol. Phys. 80, 25 (1993); R.J. Wheatley and W.J. Meath J. Chem. Phys. 179, 341 (1994); R.J. Wheatley and W.J. Meath,J. Chem. Phys. 203, 209 (1996). C. Douketis,G. Scoles, S. Marchetti, M. Zen and A. J. Thakkar, J. Chem. Phys. 76, 3057 (1982).

  4. Dynamic full field optical coherence tomography: subcellular metabolic contrast revealed in tissues by interferometric signals temporal analysis

    PubMed Central

    Apelian, Clement; Harms, Fabrice; Thouvenin, Olivier; Boccara, A. Claude

    2016-01-01

    We developed a new endogenous approach to reveal subcellular metabolic contrast in fresh ex vivo tissues taking advantage of the time dependence of the full field optical coherence tomography interferometric signals. This method reveals signals linked with local activity of the endogenous scattering elements which can reveal cells where other OCT-based techniques fail or need exogenous contrast agents. We benefit from the micrometric transverse resolution of full field OCT to image intracellular features. We used this time dependence to identify different dynamics at the millisecond scale on a wide range of organs in normal or pathological conditions. PMID:27446672

  5. On the long range propagation of sound over irregular terrain

    NASA Technical Reports Server (NTRS)

    Howe, M. S.

    1984-01-01

    The theory of sound propagation over randomly irregular, nominally plane terrain of finite impedance is discussed. The analysis is an extension of the theory of coherent scatter originally proposed by Biot for an irregular rigid surface. It combines Biot's approach, wherein the surface irregularities are modeled by a homogeneous distribution of hemispherical bosses, with more conventional analyses in which the ground is modeled as a smooth plane of finite impedance. At sufficiently low frequencies the interaction of the surface irregularities with the nearfield of a ground-based source leads to the production of surface waves, which are effective in penetrating the ground shadow zone predicted for a smooth surface of the same impedance.

  6. On the long range propagation of sound over irregular terrain

    NASA Technical Reports Server (NTRS)

    Howe, M. S.

    1985-01-01

    The theory of sound propagation over randomly irregular, nominally plane terrain of finite impedance is discussed. The analysis is an extension of the theory of coherent scatter originally proposed by Biot for an irregular rigid surface. It combines Biot's approach, wherein the surface irregularities are modeled by a homogeneous distribution of hemispherical bosses, with more conventional analyses in which the ground is modeled as a smooth plane of finite impedance. At sufficiently low frequencies the interaction of the surface irregularities with the nearfield of a ground-based source leads to the production of surface waves, which are effective in penetrating the ground shadow zone predicted for a smooth surface of the same impedance.

  7. Periodic Landau-Zener problem in long-range migration

    SciTech Connect

    Oksengendler, B. L.; Turaeva, N. N.

    2006-09-15

    From studies of radiation effects in semiconductors at low temperatures, it is known that an interstitial atom migrates over a distance of up to 1000 A (Watkins effect). The interpretation of this effect is based on the inversion of potential energy curves of an interstitial atom in semiconductors when it changes its charge. At low temperatures, a cascade of radiationless transitions can occur between the ground and excited states of a relocalized electron, which leads to the coherent tunneling of the interstitial atom through the lattice. The description of this effect using the scattering matrix S leads to the dispersion law and to an equation for the effective mass of such a quasiparticle called an inversion.

  8. Induced Long-Range Attractive Potentials of Human Serum Albumin by Ligand Binding

    SciTech Connect

    Sato, Takaaki; Komatsu, Teruyuki; Nakagawa, Akito; Tsuchida, Eishun

    2007-05-18

    Small-angle x-ray scattering and dielectric spectroscopy investigation on the solutions of recombinant human serum albumin and its heme hybrid revealed that heme incorporation induces a specific long-range attractive potential between protein molecules. This is evidenced by the enhanced forward intensity upon heme binding, despite no hindrance to rotatory Brownian motion, unbiased colloid osmotic pressure, and discontiguous nearest-neighbor distance, confirming monodispersity of the proteins. The heme-induced potential may play a trigger role in recognition of the ligand-filled human serum albumins in the circulatory system.

  9. Ultralong-range order in the Fermi-Hubbard model with long-range interactions

    NASA Astrophysics Data System (ADS)

    van Loon, Erik G. C. P.; Katsnelson, Mikhail I.; Lemeshko, Mikhail

    2015-08-01

    We use the dual boson approach to reveal the phase diagram of the Fermi-Hubbard model with long-range dipole-dipole interactions. By using a large-scale finite-temperature calculation on a 64 ×64 square lattice we demonstrate the existence of a novel phase, possessing an "ultralong-range" order. The fingerprint of this phase—the density correlation function—features a nontrivial behavior on a scale of tens of lattice sites. We study the properties and the stability of the ultralong-range-ordered phase, and show that it is accessible in modern experiments with ultracold polar molecules and magnetic atoms.

  10. Long-range inversions for ocean acoustic tomography

    NASA Astrophysics Data System (ADS)

    Malanotte-Rizzoli, Paola

    1985-01-01

    Ocean acoustic tomography was proposed by Munk and Wunsch (1979) as a method for making measurements of ocean variability over large areas. After the successful demonstration of the feasibility of the idea in the 1981 three-dimensional mesoscale experiment (Ocean Tomography Group, 1982) the tomography group has proposed a new experiment to be carried out in 1986 in the eastern Pacific Ocean on ranges as long as the subtropical gyre scale. In this paper the gyre-scale experiment is simulated in the model ocean, using Holland's eddy-resolving general circulation quasi-geostrophic model. The paper addresses the following issues: (1) measurement of the heat content vertical profile horizontally averaged along the tomographic section; (2) adequacy of the linearized inverse over very long ranges and the need for its improvement; (3) possible improvements in the specification of the field statistics to obtain more accurate estimates and to measure properties like average pycnocline trends; (4) relationship of possible range-dependent information from the inversion to the assigned noise level. The results of the modeling simulation can be summarized as follows: (1) The linearized stochastic inversion needs to be improved for gyre-scale ranges providing estimates of the average heat content that have warm or cold biases. Iteration is used and shown to provide good estimates of the average heat content. (2) A smaller number of iterations is necessary if the initial estimate is improved. This can be done by including a spatial mean in the horizontal covariance function for regions of the ocean where the energy level in the mean and in the long length scales may be even more important than the mesoscale energy peak. (3) General trends like average pycnocline slopes can be estimated very well by including an inhomogeneous covariance in the inversion. (4) The estimates of the mean heat content values and of the average slopes are rather insensitive to the specified noise level

  11. Multifractal Geophysical Extremes: Nonstationarity and Long Range Correlations

    NASA Astrophysics Data System (ADS)

    Tchiguirinskaia, I.; Schertzer, D.; Lovejoy, S.

    2012-04-01

    Throughout the world, extremes in environmental sciences are of prime importance. They are key variables not only for risk assessments and engineering designs (e.g. of dams and bridges), but also for resource management (e.g. water and energy) and for land use. A better understanding of them is more and more indispensable in settling the debate on their possible climatological evolution. Whereas it took decades before a uniform technique for estimating flow frequencies within a stationary framework, it is often claimed that « stationarity is dead ! ». The fact that geophysical and environmental fields are variable over a wider range of scales than previously thought require to go beyond the limits of the (classical) Extreme Value Theory (EVT). Indeed, long-range correlations are beyond the scope of the classical EVT theory. We show that multifractal concepts and techniques are particularly appealing because they can effectively deal with a cascade of interactions concentrating for instance energy, liquid water, etc. into smaller and smaller space-time domains. Furthermore, a general outcome of these cascade processes -which surprisingly was realized only rather recently- is that rather independently of their details they yield probability distributions with power-law fall-offs, often called (asymptotic) Pareto or Zipf laws. We discuss the corresponding probability distributions of their maxima and its relationship with the Frechet law. We use these multifractal techniques to investigate the possibility of using very short or incomplete data records for reliable statistical predictions of the extremes. In particular we assess the multifractal parameter uncertainty with the help of long synthetic multifractal series and their sub-samples, in particular to obtain an approximation of confidence intervals that would be particularly important for the predictions of multifractal extremes. We finally illustrate the efficiency of this approach with its application to

  12. Long range electron transfer in helical polyproline II oligopeptides

    NASA Astrophysics Data System (ADS)

    Ogawa, Michael Y.; Moreira, Icaro; Wishart, James F.; Isied, Stephan S.

    1993-10-01

    A series of binuclear donor-acceptor complexes with helical polyproline bridges [(bpy) 2Ru IIL-(Pro) n-apy-Ru III(NH 3) 5] 5+, n = 6, 7, 9, where L = 4-carboxy-4'-methyl-2,2'-bipyridine, bpy = 4,4'-bipyridine, and apy = 4-aminopyridine, were synthesized and characterized by absorption spectra, electrochemistry and HPLC. The CD spectra of the complexes confirm that they exist in the helical polyproline II structure. Intramolecular electron transfer within these complexes was studied by generating the [(bpy) 2Ru IL ·-(Pro) n-apy-Ru III(NH 3) 5] intermediate from the reaction of eaq (from pulse radiolysis) with the [(bpy) 2Ru IIL-(Pro) n-apy-Ru III(NH 3) 5] species in aqueous solution. The driving force for this reaction is estimated to be |Δ G0| ≈ 1.5 V. The rates ( k, 25°C) and activation parameters (Δ H‡ (kcal/mol), Δ S‡ (eu)) for the intramolecular electron transfer were found to be: 1.08×10 5 s -1, 5.6, -17; 6.40 × 10 4 s -1, 5.1, -19; 1.91 × 10 4 s -1, 4.0, and -26 for n = 6, 7, 9 respectively. The rate ( k, 25°C) and activation parameters (Δ H‡ (kcal/mol), Δ S‡ (eu)) for the intermolecular reaction between [(bpy) 2Ru IL ·] and [(NH 3) 5Ru III-apy-Pro] were found to be 2.1 × 10 9 M -1 s -1, 3.3 and -5. This series extends our studies of the distance dependence of rate versus the number of helical prolines bridging a donor and acceptor ruthenium site to a metal-to-metal distance ≈ 40 Å. The weak dependence of rate versus the number of prolines observed for n = 6, 7, and 9 is very similar to that observed earlier for [(bpy) 2Ru IIL-(Pro) n-Co III(NH 3) 5], n = 4-6. The rapid rates observed at these long distances show that long range electron transfer can be observed between an appropriate donor and acceptor directly connected to the proline bridge via peptide bonds at distances similar to the diameter of a small protein.

  13. Long-range electron transfer in biomolecules. Tunneling or hopping?

    PubMed

    Voityuk, Alexander A

    2011-10-27

    Two competing mechanisms are relevant for long-range electron transfer (ET) in biomolecules: direct electron tunneling between donor (D) and acceptor (A), D → A, and multistep hopping D → X → A, where an electron or an electron hole is transiently localized on intermediate sites X. Which of these mechanisms dominates the ET reaction is determined by the arrangement and electronic properties of the redox centers. For thermal ET, it is shown that single-step tunneling is overcome by hopping when the energy gap E between D and X is smaller than the crossover barrier E(C), E(C) = (ΔG/2) + (3/4)k(B)TβR(DA), where ΔG is the driving force, β the decay parameter, and R(DA) the donor-acceptor distance. In proteins at T = 300 K, hopping will dominate when E < E(C) = (ΔG/2) + (R(DA)/50) (E and ΔG are in eV, R(DA) in Å); single-step tunneling will be operative when E > E(C). Thus, one can explore the ET mechanism using three quantities E, ΔG, and R(DA). When ΔG = 0 and E = 0.5 eV (the difference in redox potentials of D and X is 0.5 V), two-step hopping D → X → A will be favored at R(DA) >25 Å. In protein ET chains, the distance between redox cofactors is often smaller than 20 Å, but the gap E between the cofactors and surrounding amino acid residues is larger than 0.5 eV. Therefore, ET in the systems should occur by single-step tunneling D → A. In the activationless regime (ΔG ≈ -λ, λ is the reorganization energy) often observed for photoinduced ET, the crossing point energy is determined by E(C) = (2λkTβR(DA))(1/2) - λ. The suggested expressions for the threshold barrier may be useful to predict the ET mechanism in natural and artificial redox systems.

  14. Local orderings in long-range-disordered bismuth-layered intergrowth structure

    SciTech Connect

    Zhang, Faqiang; Li, Yongxiang; Gu, Hui; Gao, Xiang

    2014-04-01

    A series of intergrowth bismuth-layered (Bi{sub 3}TiNbO{sub 9}){sub 2}(Bi{sub 4}Ti{sub 3}O{sub 12}) (2{sub 2}3) ceramics were prepared by conventional solid-state reaction to study the characteristics of the local orderings in long-range-disordered intergrowth structures. High-resolution high-angle annular dark-field (HAADF) imaging reveals the intergrowth structure composed of mixtures of -23-, -223-, -2223- and -22- sequences, while the -223- structure is the thermodynamic stable state of this intergrowth system. It was confirmed by the crystals of recurrent -223- structure prepared by self-flux method and the nature of the local ordering was discussed from their differences in repeating units. The statistics show that when repeating units reach 4 or higher, the independent -223- intergrowth ordering emerges clearly among the competing associated orderings. We infer it is the kinetic factor that induces local compositional variance to result in long-range disordered intergrowth structures. - Graphical abstract: The long-range-disordered intergrowth structure in a (Bi{sub 3}TiNbO{sub 9}){sub 2}(Bi{sub 4}Ti{sub 3}O{sub 12}) (2{sub 2}3) grain, which is composed of various types of local orderings, such as -22-, -23- and -223-. - Highlights: • The characteristic of the long-range-disordered (Bi{sub 3}TiNbO{sub 9}){sub 2}(Bi{sub 4}Ti{sub 3}O{sub 12}) (2{sub 2}3) structure was statistically analyzed, and the ordered -223- structure was speculated to be the thermodynamic stable state of the system. • The crystals of the -223- structure were successfully prepared for the first time by self-melt method. • The lower limit of the repeating units (L) to uniquely determine an independent intergrowth structure was speculated to be L=4. • The analysis inferred that the kinetic process is the controlling factor to limit the structural continuity and induce the long-range-disordered intergrowth structure.

  15. Off-diagonal long-range order, restricted gauge transformations, and Aharonov-Bohm effect in conductors

    SciTech Connect

    Peshkin, M.

    1996-03-01

    The electrons in a conductor surrounding an external magnetic field are acted on by a vector potential that cannot be removed by a gauge transformation. Nevertheless, a macroscopic normal conductor can experience no Aharonov-Bohm (AB) effect. That is proved by assuming only that a normal conductor lacks off-diagonal long-range order (ODLRO), which means that the electrons lack long-range phase coherence. Then by restricting the Hilbert space to density matrices which lack ODLRO, one can introduce a restricted gauge transformation that removes the interaction of the conductor with the vector potential. Consequently, the AB effect on a beam particle is not shielded by the conductor. {copyright} {ital 1996 The American Physical Society.}

  16. 2006 Long Range Development Plan Final Environmental ImpactReport

    SciTech Connect

    Philliber, Jeff

    2007-01-22

    This environmental impact report (EIR) has been prepared pursuant to the applicable provisions of the California Environmental Quality Act (CEQA) and its implementing guidelines (CEQA Guidelines), and the Amended University of California Procedures for Implementation of the California Environmental Quality Act (UC CEQA Procedures). The University of California (UC or the University) is the lead agency for this EIR, which examines the overall effects of implementation of the proposed 2006 Long Range Development Plan (LRDP; also referred to herein as the 'project' for purposes of CEQA) for Lawrence Berkeley National Laboratory (LBNL; also referred to as 'Berkeley Lab,' 'the Laboratory,' or 'the Lab' in this document). An LRDP is a land use plan that guides overall development of a site. The Lab serves as a special research campus operated by the University employees, but it is owned and financed by the federal government and as such it is distinct from the UC-owned Berkeley Campus. As a campus operated by the University of California, the Laboratory is required to prepare an EIR for an LRDP when one is prepared or updated pursuant to Public Resources Code Section 21080.09. The adoption of an LRDP does not constitute a commitment to, or final decision to implement, any specific project, construction schedule, or funding priority. Rather, the proposed 2006 LRDP describes an entire development program of approximately 980,000 gross square feet of new research and support space construction and 320,000 gross square feet of demolition of existing facilities, for a total of approximately 660,000 gross square feet of net new occupiable space for the site through 2025. Specific projects will undergo CEQA review at the time proposed to determine what, if any, additional review is necessary prior to approval. As described in Section 1.4.2, below, and in Chapter 3 of this EIR (the Project Description), the size of the project has been reduced since the Notice of Preparation for

  17. Long range wind lidars based on novel high spectral brilliance all-fibered sources

    NASA Astrophysics Data System (ADS)

    Lombard, L.; Dolfi-Bouteyre, A.; Besson, C.; Augère, B.; Bourdon, P.; Durécu, A.; Goular, D.; Le Gouët, J.; Planchat, C.; Renard, W.; Valla, M.; Canat, G.

    2015-10-01

    New Lidar applications related to aircraft safety in the area of an airport include mapping wind velocity and monitoring turbulences within a radius longer than 8km in a short acquisition time (360° map in 1 minute). During landing and takeoff, a minimal distance separation between aircrafts is set by referring to wake turbulence categories. However, it was shown that wake vortices can dissipate quicker because of atmospheric turbulence (characterized by eddy dissipation rate - EDR) or can be transported out of the way on oncoming traffic by cross-winds. Long range scanning Lidars provide radial wind data that can be used to calculate EDR. To reach long range within a short acquisition time, coherent wind Lidars require high power (~kW), narrow linewidth (few MHz) pulsed laser sources with nearly TF limited pulse duration (~1μs). Eyesafe, all-fiber laser sources based on MOPFA (master oscillator, power fiber amplifier) architecture offer many advantages over bulk sources such as low sensitivity to vibrations, efficiency and versatility. However, narrow linewidth pulsed fiber lasers and amplifiers are usually limited by nonlinear effects such as stimulated Brillouin scattering (SBS) to 300W with commercial fibers. We investigated various solutions to push this limit further. For example, a source based on a new fiber composition yielded a peak power of 1120W for 650ns pulse duration with excellent beam quality. Based on these innovative solutions we built a Lidar with a record range of 16km in 0.1s averaging time. In this proceeding, we present some recent results obtained with our wind Lidars based on these high power sources with record ranges. EDR measurements using the developed algorithm based on structure function calculation are presented, as well as its validation with simulations and measurements campaign results.

  18. Long-range order in a high-density electron-hole system at room temperature during superradiant phase transition

    NASA Astrophysics Data System (ADS)

    Vasil'ev, Peter P.; Olle, Vojtech; Penty, Richard V.; White, Ian H.

    2013-11-01

    We have experimentally investigated the formation of off-diagonal long-range order and non-equilibrium BEC-like condensation in GaAs/AlGaAs heterostructures during superradiant (SR) emission at room temperature. The conclusive evidence of the establishment of phase coherence over a macroscopic range during the superradiant quantum phase transition is reported. The first-order spatial correlation function of the e-h system is determined by evaluating interference patterns of SR emission using Young's double slit.

  19. An Approach to Long-Range Planning in the 1980's. AIR Forum 1981 Paper.

    ERIC Educational Resources Information Center

    Lueck, Lowell A.

    Key ingredients of long-range planning described in the literature during the last 10 years, the role of an office of institutional research, and a coordinated long-range planning process as it might occur in a public four-year college or university are described. A successful long-range planning process is characterized by centralized…

  20. An Approach to Long-Range Planning in the 1980's. AIR Forum 1981 Paper.

    ERIC Educational Resources Information Center

    Lueck, Lowell A.

    Key ingredients of long-range planning described in the literature during the last 10 years, the role of an office of institutional research, and a coordinated long-range planning process as it might occur in a public four-year college or university are described. A successful long-range planning process is characterized by centralized…

  1. 7 CFR 1717.604 - Long-range engineering plans and construction work plans.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 11 2011-01-01 2011-01-01 false Long-range engineering plans and construction work... AND GUARANTEED ELECTRIC LOANS Operational Controls § 1717.604 Long-range engineering plans and construction work plans. (a) All borrowers are required to maintain up-to-date long-range engineering plans and...

  2. 7 CFR 1717.604 - Long-range engineering plans and construction work plans.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 11 2013-01-01 2013-01-01 false Long-range engineering plans and construction work... AND GUARANTEED ELECTRIC LOANS Operational Controls § 1717.604 Long-range engineering plans and construction work plans. (a) All borrowers are required to maintain up-to-date long-range engineering plans and...

  3. 7 CFR 1717.604 - Long-range engineering plans and construction work plans.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 11 2014-01-01 2014-01-01 false Long-range engineering plans and construction work... AND GUARANTEED ELECTRIC LOANS Operational Controls § 1717.604 Long-range engineering plans and construction work plans. (a) All borrowers are required to maintain up-to-date long-range engineering plans and...

  4. 7 CFR 1717.604 - Long-range engineering plans and construction work plans.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 11 2010-01-01 2010-01-01 false Long-range engineering plans and construction work... AND GUARANTEED ELECTRIC LOANS Operational Controls § 1717.604 Long-range engineering plans and construction work plans. (a) All borrowers are required to maintain up-to-date long-range engineering plans and...

  5. 7 CFR 1717.604 - Long-range engineering plans and construction work plans.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 11 2012-01-01 2012-01-01 false Long-range engineering plans and construction work... AND GUARANTEED ELECTRIC LOANS Operational Controls § 1717.604 Long-range engineering plans and construction work plans. (a) All borrowers are required to maintain up-to-date long-range engineering plans and...

  6. Role of long-range intermolecular forces in the formation of inorganic nanoparticle clusters.

    PubMed

    Gibbs, G V; Crawford, T D; Wallace, A F; Cox, D F; Parrish, R M; Hohenstein, E G; Sherrill, C D

    2011-11-17

    An understanding of the role played by intermolecular forces in terms of the electron density distribution is fundamental to the understanding of the self-assembly of molecules in the formation of a molecular crystal. Using ab initio methods capable of describing both short-range intramolecular interactions and long-range London dispersion interactions arising from electron correlation, analyses of inorganic dimers of As(4)S(4) and As(4)O(6) molecules cut from the structures of realgar and arsenolite, respectively, reveal that the molecules adopt a configuration that closely matches that observed for the crystal. Decomposition of the interaction energies using symmetry-adapted perturbation theory reveals that both model dimers feature significant stabilization from electrostatic forces as anticipated by a Lewis acid/Lewis base picture of the interaction. London dispersion forces also contribute significantly to the interaction, although they play a greater role in the realgar structure near equilibrium than in arsenolite.

  7. Fast Faraday fading of long range satellite signals.

    NASA Technical Reports Server (NTRS)

    Heron, M. L.

    1972-01-01

    20 MHz radio signals have been received during the day from satellite Beacon-B when it was below the optical horizon by using a bank of narrow filters to improve the signal to noise ratio. The Faraday fading rate becomes constant, under these conditions, at a level determined by the plasma frequency just below the F-layer peak. Variations in the Faraday fading rate reveal fluctuations in the electron density near the peak, while the rate of attaining the constant level depends on the shape of the electron density profile.

  8. Aggregation of heteropolyanions in aqueous solutions exhibiting short-range attractions and long-range repulsions

    DOE PAGES

    Bera, Mrinal K.; Qiao, Baofu; Seifert, Soenke; ...

    2015-12-15

    Charged colloids and proteins in aqueous solutions interact via short-range attractions and long-range repulsions (SALR) and exhibit complex structural phases. These include homogeneously dispersed monomers, percolated monomers, clusters, and percolated clusters. We report the structural architectures of simple charged systems in the form of spherical, Keggin-type heteropolyanions (HPAs) by small-angle X-ray scattering (SAXS) and molecular dynamics (MD) simulations. Structure factors obtained from the SAXS measurements show that the HPAs interact via SALR. Concentration and temperature dependences of the structure factors for HPAs with –3e (e is the charge of an electron) charge are consistent with a mixture of nonassociated monomersmore » and associated randomly percolated monomers, whereas those for HPAs with –4e and –5e charges exhibit only nonassociated monomers in aqueous solutions. Our experiments show that the increase in magnitude of the charge of the HPAs increases their repulsive interactions and inhibits their aggregation in aqueous solutions. MD simulations were done to reveal the atomistic scale origins of SALR between HPAs. As a result, the short-range attractions result from water or proton-mediated hydrogen bonds between neighboring HPAs, whereas the long-range repulsions are due to the distributions of ions surrounding the HPAs.« less

  9. Aggregation of heteropolyanions in aqueous solutions exhibiting short-range attractions and long-range repulsions

    SciTech Connect

    Bera, Mrinal K.; Qiao, Baofu; Seifert, Soenke; Burton-Pye, Benjamin P.; Monica Olvera de la Cruz; Antonio, Mark R.

    2015-12-15

    Charged colloids and proteins in aqueous solutions interact via short-range attractions and long-range repulsions (SALR) and exhibit complex structural phases. These include homogeneously dispersed monomers, percolated monomers, clusters, and percolated clusters. We report the structural architectures of simple charged systems in the form of spherical, Keggin-type heteropolyanions (HPAs) by small-angle X-ray scattering (SAXS) and molecular dynamics (MD) simulations. Structure factors obtained from the SAXS measurements show that the HPAs interact via SALR. Concentration and temperature dependences of the structure factors for HPAs with –3e (e is the charge of an electron) charge are consistent with a mixture of nonassociated monomers and associated randomly percolated monomers, whereas those for HPAs with –4e and –5e charges exhibit only nonassociated monomers in aqueous solutions. Our experiments show that the increase in magnitude of the charge of the HPAs increases their repulsive interactions and inhibits their aggregation in aqueous solutions. MD simulations were done to reveal the atomistic scale origins of SALR between HPAs. As a result, the short-range attractions result from water or proton-mediated hydrogen bonds between neighboring HPAs, whereas the long-range repulsions are due to the distributions of ions surrounding the HPAs.

  10. Cell type-specific long-range connections of basal forebrain circuit

    PubMed Central

    Do, Johnny Phong; Xu, Min; Lee, Seung-Hee; Chang, Wei-Cheng; Zhang, Siyu; Chung, Shinjae; Yung, Tyler J; Fan, Jiang Lan; Miyamichi, Kazunari; Luo, Liqun; Dan, Yang

    2016-01-01

    The basal forebrain (BF) plays key roles in multiple brain functions, including sleep-wake regulation, attention, and learning/memory, but the long-range connections mediating these functions remain poorly characterized. Here we performed whole-brain mapping of both inputs and outputs of four BF cell types – cholinergic, glutamatergic, and parvalbumin-positive (PV+) and somatostatin-positive (SOM+) GABAergic neurons – in the mouse brain. Using rabies virus -mediated monosynaptic retrograde tracing to label the inputs and adeno-associated virus to trace axonal projections, we identified numerous brain areas connected to the BF. The inputs to different cell types were qualitatively similar, but the output projections showed marked differences. The connections to glutamatergic and SOM+ neurons were strongly reciprocal, while those to cholinergic and PV+ neurons were more unidirectional. These results reveal the long-range wiring diagram of the BF circuit with highly convergent inputs and divergent outputs and point to both functional commonality and specialization of different BF cell types. DOI: http://dx.doi.org/10.7554/eLife.13214.001 PMID:27642784

  11. Long-range ferrimagnetic order in a two-dimensional supramolecular Kondo lattice

    NASA Astrophysics Data System (ADS)

    Girovsky, Jan; Nowakowski, Jan; Ali, Md. Ehesan; Baljozovic, Milos; Rossmann, Harald R.; Nijs, Thomas; Aeby, Elise A.; Nowakowska, Sylwia; Siewert, Dorota; Srivastava, Gitika; Wäckerlin, Christian; Dreiser, Jan; Decurtins, Silvio; Liu, Shi-Xia; Oppeneer, Peter M.; Jung, Thomas A.; Ballav, Nirmalya

    2017-05-01

    Realization of long-range magnetic order in surface-supported two-dimensional systems has been challenging, mainly due to the competition between fundamental magnetic interactions as the short-range Kondo effect and spin-stabilizing magnetic exchange interactions. Spin-bearing molecules on conducting substrates represent a rich platform to investigate the interplay of these fundamental magnetic interactions. Here we demonstrate the direct observation of long-range ferrimagnetic order emerging in a two-dimensional supramolecular Kondo lattice. The lattice consists of paramagnetic hexadeca-fluorinated iron phthalocyanine (FeFPc) and manganese phthalocyanine (MnPc) molecules co-assembled into a checkerboard pattern on single-crystalline Au(111) substrates. Remarkably, the remanent magnetic moments are oriented in the out-of-plane direction with significant contribution from orbital moments. First-principles calculations reveal that the FeFPc-MnPc antiferromagnetic nearest-neighbour coupling is mediated by the Ruderman-Kittel-Kasuya-Yosida exchange interaction via the Au substrate electronic states. Our findings suggest the use of molecular frameworks to engineer novel low-dimensional magnetically ordered materials and their application in molecular quantum devices.

  12. Long-range ferrimagnetic order in a two-dimensional supramolecular Kondo lattice.

    PubMed

    Girovsky, Jan; Nowakowski, Jan; Ali, Md Ehesan; Baljozovic, Milos; Rossmann, Harald R; Nijs, Thomas; Aeby, Elise A; Nowakowska, Sylwia; Siewert, Dorota; Srivastava, Gitika; Wäckerlin, Christian; Dreiser, Jan; Decurtins, Silvio; Liu, Shi-Xia; Oppeneer, Peter M; Jung, Thomas A; Ballav, Nirmalya

    2017-05-22

    Realization of long-range magnetic order in surface-supported two-dimensional systems has been challenging, mainly due to the competition between fundamental magnetic interactions as the short-range Kondo effect and spin-stabilizing magnetic exchange interactions. Spin-bearing molecules on conducting substrates represent a rich platform to investigate the interplay of these fundamental magnetic interactions. Here we demonstrate the direct observation of long-range ferrimagnetic order emerging in a two-dimensional supramolecular Kondo lattice. The lattice consists of paramagnetic hexadeca-fluorinated iron phthalocyanine (FeFPc) and manganese phthalocyanine (MnPc) molecules co-assembled into a checkerboard pattern on single-crystalline Au(111) substrates. Remarkably, the remanent magnetic moments are oriented in the out-of-plane direction with significant contribution from orbital moments. First-principles calculations reveal that the FeFPc-MnPc antiferromagnetic nearest-neighbour coupling is mediated by the Ruderman-Kittel-Kasuya-Yosida exchange interaction via the Au substrate electronic states. Our findings suggest the use of molecular frameworks to engineer novel low-dimensional magnetically ordered materials and their application in molecular quantum devices.

  13. Long-range ferrimagnetic order in a two-dimensional supramolecular Kondo lattice

    PubMed Central

    Girovsky, Jan; Nowakowski, Jan; Ali, Md. Ehesan; Baljozovic, Milos; Rossmann, Harald R.; Nijs, Thomas; Aeby, Elise A.; Nowakowska, Sylwia; Siewert, Dorota; Srivastava, Gitika; Wäckerlin, Christian; Dreiser, Jan; Decurtins, Silvio; Liu, Shi-Xia; Oppeneer, Peter M.; Jung, Thomas A.; Ballav, Nirmalya

    2017-01-01

    Realization of long-range magnetic order in surface-supported two-dimensional systems has been challenging, mainly due to the competition between fundamental magnetic interactions as the short-range Kondo effect and spin-stabilizing magnetic exchange interactions. Spin-bearing molecules on conducting substrates represent a rich platform to investigate the interplay of these fundamental magnetic interactions. Here we demonstrate the direct observation of long-range ferrimagnetic order emerging in a two-dimensional supramolecular Kondo lattice. The lattice consists of paramagnetic hexadeca-fluorinated iron phthalocyanine (FeFPc) and manganese phthalocyanine (MnPc) molecules co-assembled into a checkerboard pattern on single-crystalline Au(111) substrates. Remarkably, the remanent magnetic moments are oriented in the out-of-plane direction with significant contribution from orbital moments. First-principles calculations reveal that the FeFPc-MnPc antiferromagnetic nearest-neighbour coupling is mediated by the Ruderman–Kittel–Kasuya–Yosida exchange interaction via the Au substrate electronic states. Our findings suggest the use of molecular frameworks to engineer novel low-dimensional magnetically ordered materials and their application in molecular quantum devices. PMID:28530247

  14. Short- and Long-Range Attractive Forces That Influence the Structure of Montmorillonite Osmotic Hydrates.

    PubMed

    Tester, Chantel C; Aloni, Shaul; Gilbert, Benjamin; Banfield, Jillian F

    2016-11-22

    Clay swelling is a colloidal phenomenon that has a large influence on flow and solute migration in soils and sediments. While models for clay swelling have been proposed over many years, debate remains as to the interaction forces that combine to produce the observed swelling behavior. Using cryogenic transmission electron microscopy (cryo-TEM) and small-angle X-ray scattering, we study the influence of salinity, in combination with layer charge, interlayer cation, and particle size, on montmorillonite swelling. We observe a decrease in swelling with increased layer charge, increased cation charge, and decreased cation hydration, each indicative of the critical influence of Coulombic attraction between the negatively charged layers and interlayer cations. Cryo-TEM images of individual montmorillonite particles also reveal that swelling is dependent upon the number of layers in a particle. Calculations of the van der Waals (vdW) interaction based on new measurements of Hamaker coefficients confirm that long-range vdW interactions extend beyond near-neighbor layer interactions and result in a decrease in layer spacing with a larger number of layers. This work clarifies the short- and long-range attractive interactions that govern clay structure and ultimately the stability and permeability of hydrated clays in the environment.

  15. Quasi-phase matching for efficient long-range plasmonic third-harmonic generation via graphene.

    PubMed

    Nasari, Hadiseh; Abrishamian, Mohammad Sadegh

    2015-12-01

    We propose and numerically investigate an efficient method for long-range third-harmonic generation (THG) of propagating surface plasmon polaritons (SPP) waves on graphene sheets for nonlinear plasmonic purposes in the terahertz (THZ) gap region of the electromagnetic spectrum via a developed nonlinear finite-difference time-domain technique. We reveal that although extended and unmodulated graphene sheets with low Fermi levels can offer high-conversion efficiency (CE) for SPP THG at short distances, suitable for miniaturized plasmonic circuits, they suffer from inherent absorption loss induced by graphene that noticeably reduces the CE of the THG at long ranges. We suggest a structure benefiting from low Fermi-level graphene regions of strong nonlinear response as oscillators and high Fermi-level ones of low loss as a propagating medium in a periodic manner, which satisfies the quasi-phase matching condition and shows considerable efficiency improvement at long propagation distances. We predict that such a configuration can find valuable potential applications in the realm of nonlinear THz plasmonics for generating new frequencies and also in spectroscopy, signal processing, and so on.

  16. Superradiant laser: Effect of long-range dipole-dipole interaction

    NASA Astrophysics Data System (ADS)

    Jen, H. H.

    2016-11-01

    We theoretically investigate the effect of long-range dipole-dipole interaction (LRDDI) on a superradiant laser (SL). This effect is induced from the atom-photon interaction in the dissipation process. In the bad-cavity limit usually performed to initiate SL, we demonstrate that cavity photon number oscillates as an interparticle distance of the atoms varies. Similarly the atom-atom coherence alternates with signs, showing critical transitions alternatively in SL operations. This suggests a complexity of the collective effect emerging in a large ensemble of atoms. Therefore this effect in a SL cannot be simply interpreted by only a part of the whole ensemble. We numerically solve for a steady-state SL including the spatially dependent LRDDI, and locate the maximal cavity photon number and the minimal spectral linewidth respectively at the optimal atomic separations in the setting of an equidistant atomic array. The scaling of a finite number of atoms shows that a steady-state SL outperforms the one without LRDDI, which allows for probing narrow atomic transitions and is potentially useful for precision measurements and next-generation optical clocks.

  17. Tailored long range forces on polarizable particles by collective scattering of broadband radiation

    NASA Astrophysics Data System (ADS)

    Holzmann, D.; Ritsch, H.

    2016-10-01

    Collective coherent light scattering by polarizable particles creates surprisingly strong, long range inter-particle forces originating from interference of the light scattered by different particles. While for monochromatic laser beams this interaction decays with the inverse distance, we show here that in general the effective interaction range and geometry can be controlled by the illumination bandwidth and geometry. As generic example we study the modifications inter-particle forces within a 1D chain of atoms trapped in the field of a confined optical nanofiber mode. For two particles we find short range attraction as well as optical binding at multiple distances. The range of stable distances shrinks with increasing light bandwidth and for a very large bandwidth field as e.g. blackbody radiation. We find a strongly attractive potential up to a critical distance beyond which the force gets repulsive. Including multiple scattering can even lead to the appearance of a stable configuration at a large distance. Such broadband scattering forces should be observable contributions in ultra-cold atom interferometers or atomic clocks setups. They could be studied in detail in 1D geometries with ultra-cold atoms trapped along or within an optical nanofiber. Broadband radiation force interactions might also contribute in astrophysical scenarios as illuminated cold dust clouds.

  18. Magnetic Exchange Interactions in Long Range Ordered Diluted Organometallic Semiconductors

    NASA Astrophysics Data System (ADS)

    Rawat, Naveen; Manning, Lane; Furis, Madalina

    2015-03-01

    Exchange Interactions in diluted organometallic crystalline thin films of Phthalocyanines made of a mixture of organo-soluble derivatives of metal-free (H2Pc) molecule and MnPc is investigated. The tuning of optical and magnetic properties in organometallics is driven by their emergence in optoelectronic applications involving flexible electronics. Thin films with metal to metal-free Pc ratios ranging from 1: 1 to 1:10 were fabricated using solution processing that produces macroscopic grains. In the case of Mn-Pc, our previos measurements showed enhanced hybridization of ligand π-electronic states with the Mn d-orbitals as well as indirect exchange interaction similar to that of RKKY type exchange. The evolution of Zeeman splitting of specific MCD-active states resulted in enhanced effective π-electrons g-factors, analogous to diluted magnetic semiconductors (DMS) systems. Recent Variable temperature Magnetic Circular Dichroism (VTVH-MCD) measurements has now revealed that the exchange interaction is Antiferromagnetic. Recent MCD data for mixed derivatives will be presented along with their temperature dependance that further probes this exchange interaction. NSF award 1056589

  19. Long range acoustic measurements of an undersea volcano.

    PubMed

    Heaney, Kevin D; Campbell, Richard L; Snellen, Mirjam

    2013-10-01

    A seamount 8 km southeast of Sarigan Island erupted on 29 May 2010 and was visually observed. The recordings on two sets of hydrophones, operated by International Monitoring System (IMS) of the Comprehensive Test Ban Treaty Organization (CTBTO) are analyzed. Each array is a triplet of axial single hydrophones deployed as a 2 km triangle. Measurements of acoustic intensity for the path to the southern triplet are on the order of 6 dB lower than those received on the northern triplet. Temporal cross-correlation beamforming estimation is performed and the estimated arrival angles for the two arrays, 265° and 267° were consistent with the predicted geodesic arrival of 264.6° and 267.8°, respectively. Cross-correlation between single phones on the northern and southern arrays reveals a peak at 266°, with a cross-correlation of 0.1. Nx2D parabolic equation modeling predicts complete blockage due to seamount interaction along the geodesic path. Overprediction of the seamount blockage indicates that the 2D approximation is incorrect, and three-dimensional propagation must be used to explain the observations. This is demonstrated by the computation of the Adiabatic Mode Parabolic Equation Transmission Loss, which predicts a 5-10 dB lower reception at the southern site.

  20. Coherent energy scale revealed by ultrafast dynamics of UX3 (X = Al, Sn, Ga) single crystals

    NASA Astrophysics Data System (ADS)

    Nair, Saritha K.; Zhu, J.-X.; Sarrao, J. L.; Taylor, A. J.; Chia, Elbert E. M.

    2012-09-01

    The temperature dependence of relaxation dynamics of UX3 (X = Al, Ga, Sn) compounds is studied using the time-resolved pump-probe technique in reflectance geometry. For UGa3, our data are consistent with the formation of a spin density wave gap as evidenced from the quasidivergence of the relaxation time τ near the Néel temperature TN. For UAl3 and USn3, the relaxation dynamics shows a change from single-exponential to two-exponential behavior below a particular temperature, suggestive of coherence formation of the 5f electrons with the conduction band electrons. This particular temperature can be attributed to the spin fluctuation temperature Tsf, a measure of the strength of Kondo coherence. Our Tsf is consistent with other data such as resistivity and susceptibility measurements. The temperature dependence of the relaxation amplitude and time of UAl3 and USn3 were also fitted by the Rothwarf-Taylor model. Our results show that ultrafast optical spectroscopy is sensitive to c-f Kondo hybridization in the f-electron systems.

  1. Revealing anisotropic properties of cornea at different intraocular pressures using optical coherence elastography

    NASA Astrophysics Data System (ADS)

    Li, Jiasong; Singh, Manmohan; Han, Zhaolong; Wu, Chen; Nair, Achuth; Aglyamov, Salavat R.; Twa, Michael D.; Larin, Kirill V.

    2016-03-01

    In this study we have evaluated the elastic anisotropy of porcine corneas with increasing intraocular pressures (IOPs) using a noncontact optical coherence elastography (OCE) technique. A focused air-pulse induced low amplitude (<=10 μm) elastic waves in fresh porcine corneas (n=9) in situ in the whole eye-globe configuration. A phase-stabilized swept source optical coherence elastography (PhS-SSOCE) system imaged the propagation of the elastic wave in different stepped radial directions. A closed-loop feedback system was utilized to artificially manipulate the IOP, and OCE measurements were repeated while the IOP was increased in 5 mmHg increments from 15 to 30 mmHg. The OCE measurements demonstrated that the elastic anisotropy of the cornea became more pronounced at higher IOPs, and that there were distinct radial angles of higher and lower stiffness. The presented noncontact OCE method was capable of detecting and assessing the corneal elastic anisotropy as a function of IOP. Due to the noninvasive nature and small amplitude of the elastic wave, this method may be able to provide additional information about corneal health and integrity in vivo.

  2. Photon Devil’s staircase: photon long-range repulsive interaction in lattices of coupled resonators with Rydberg atoms

    PubMed Central

    Zhang, Yuanwei; Fan, Jingtao; Liang, J.-Q.; Ma, Jie; Chen, Gang; Jia, Suotang; Nori, Franco

    2015-01-01

    The realization of strong coherent interactions between individual photons is a long-standing goal in science and engineering. In this report, based on recent experimental setups, we derive a strong photon long-range repulsive interaction, by controlling the van der Waals repulsive force between Cesium Rydberg atoms located inside different cavities in extended Jaynes-Cummings-Hubbard lattices. We also find novel quantum phases induced by this photon long-range repulsive interaction. For example, without photon hopping, a photon Devil’s staircase, induced by the breaking of long-range translation symmetry, can emerge. If photon hopping occurs, we predict a photon-floating solid phase, due to the motion of particle- and hole-like defects. More importantly, for a large chemical potential in the resonant case, the photon hopping can be frozen even if the hopping term exists. We call this new phase the photon-frozen solid phase. In experiments, these predicted phases could be detected by measuring the number of polaritons via resonance fluorescence. PMID:26108705

  3. Optical coherence tomography segmentation reveals ganglion cell layer pathology after optic neuritis.

    PubMed

    Syc, Stephanie B; Saidha, Shiv; Newsome, Scott D; Ratchford, John N; Levy, Michael; Ford, E'tona; Crainiceanu, Ciprian M; Durbin, Mary K; Oakley, Jonathan D; Meyer, Scott A; Frohman, Elliot M; Calabresi, Peter A

    2012-02-01

    Post-mortem ganglion cell dropout has been observed in multiple sclerosis; however, longitudinal in vivo assessment of retinal neuronal layers following acute optic neuritis remains largely unexplored. Peripapillary retinal nerve fibre layer thickness, measured by optical coherence tomography, has been proposed as an outcome measure in studies of neuroprotective agents in multiple sclerosis, yet potential swelling during the acute stages of optic neuritis may confound baseline measurements. The objective of this study was to ascertain whether patients with multiple sclerosis or neuromyelitis optica develop retinal neuronal layer pathology following acute optic neuritis, and to systematically characterize such changes in vivo over time. Spectral domain optical coherence tomography imaging, including automated retinal layer segmentation, was performed serially in 20 participants during the acute phase of optic neuritis, and again 3 and 6 months later. Imaging was performed cross-sectionally in 98 multiple sclerosis participants, 22 neuromyelitis optica participants and 72 healthy controls. Neuronal thinning was observed in the ganglion cell layer of eyes affected by acute optic neuritis 3 and 6 months after onset (P < 0.001). Baseline ganglion cell layer thicknesses did not demonstrate swelling when compared with contralateral unaffected eyes, whereas peripapillary retinal nerve fibre layer oedema was observed in affected eyes (P = 0.008) and subsequently thinned over the course of this study. Ganglion cell layer thickness was lower in both participants with multiple sclerosis and participants with neuromyelitis optica, with and without a history of optic neuritis, when compared with healthy controls (P < 0.001) and correlated with visual function. Of all patient groups investigated, those with neuromyelitis optica and a history of optic neuritis exhibited the greatest reduction in ganglion cell layer thickness. Results from our in vivo longitudinal study

  4. Picosecond x-ray strain rosette reveals direct laser excitation of coherent transverse acoustic phonons

    DOE PAGES

    Lee, Sooheyong; Williams, G. Jackson; Campana, Maria I.; ...

    2016-01-11

    Using a strain-rosette, we demonstrate the existence of transverse strain using time-resolved x-ray diffraction from multiple Bragg reflections in laser-excited bulk gallium arsenide. We find that anisotropic strain is responsible for a considerable fraction of the total lattice motion at early times before thermal equilibrium is achieved. Our measurements are described by a new model where the Poisson ratio drives transverse motion, resulting in the creation of shear waves without the need for an indirect process such as mode conversion at an interface. Finally, using the same excitation geometry with the narrow-gap semiconductor indium antimonide, we detected coherent transverse acousticmore » oscillations at frequencies of several GHz.« less

  5. Picosecond x-ray strain rosette reveals direct laser excitation of coherent transverse acoustic phonons

    SciTech Connect

    Lee, Sooheyong; Williams, G. Jackson; Campana, Maria I.; Walko, Donald A.; Landahl, Eric C.

    2016-01-11

    Using a strain-rosette, we demonstrate the existence of transverse strain using time-resolved x-ray diffraction from multiple Bragg reflections in laser-excited bulk gallium arsenide. We find that anisotropic strain is responsible for a considerable fraction of the total lattice motion at early times before thermal equilibrium is achieved. Our measurements are described by a new model where the Poisson ratio drives transverse motion, resulting in the creation of shear waves without the need for an indirect process such as mode conversion at an interface. Finally, using the same excitation geometry with the narrow-gap semiconductor indium antimonide, we detected coherent transverse acoustic oscillations at frequencies of several GHz.

  6. Revealing fine microstructural morphology in the living human retina using Optical Coherence Tomography with pancorrection

    NASA Astrophysics Data System (ADS)

    Torti, C.; Považay, B.; Hofer, B.; Unterhuber, A.; Hermann, B.; Drexler, W.

    2008-09-01

    Ultra-high speed optical coherence tomography employing an ultra-broadband light source has been combined with adaptive optics utilizing a single high stroke deformable mirror and chromatic aberration compensation. The reduction of motion artefacts, geometric and chromatic aberrations (pancorrection) permits to achieve an isotropic resolution of 2-3 μm in the human eye. The performance of this non-invasive imaging modality enables to resolve cellular structures including cone photoreceptors, nerve fibre bundles and collagenous plates of the lamina cribrosa, and retinal pigment epithelial (RPE) cells in the human retina in vivo with superior detail. Alterations of cellular morphology due to cone degeneration in a colour-blind subject are investigated in ultra-high resolution with selective depth sectioning for the first time.

  7. Picosecond x-ray strain rosette reveals direct laser excitation of coherent transverse acoustic phonons.

    PubMed

    Lee, Sooheyong; Williams, G Jackson; Campana, Maria I; Walko, Donald A; Landahl, Eric C

    2016-01-11

    Using a strain-rosette, we demonstrate the existence of transverse strain using time-resolved x-ray diffraction from multiple Bragg reflections in laser-excited bulk gallium arsenide. We find that anisotropic strain is responsible for a considerable fraction of the total lattice motion at early times before thermal equilibrium is achieved. Our measurements are described by a new model where the Poisson ratio drives transverse motion, resulting in the creation of shear waves without the need for an indirect process such as mode conversion at an interface. Using the same excitation geometry with the narrow-gap semiconductor indium antimonide, we detected coherent transverse acoustic oscillations at frequencies of several GHz.

  8. Picosecond x-ray strain rosette reveals direct laser excitation of coherent transverse acoustic phonons

    PubMed Central

    Lee, Sooheyong; Williams, G. Jackson; Campana, Maria I.; Walko, Donald A.; Landahl, Eric C.

    2016-01-01

    Using a strain-rosette, we demonstrate the existence of transverse strain using time-resolved x-ray diffraction from multiple Bragg reflections in laser-excited bulk gallium arsenide. We find that anisotropic strain is responsible for a considerable fraction of the total lattice motion at early times before thermal equilibrium is achieved. Our measurements are described by a new model where the Poisson ratio drives transverse motion, resulting in the creation of shear waves without the need for an indirect process such as mode conversion at an interface. Using the same excitation geometry with the narrow-gap semiconductor indium antimonide, we detected coherent transverse acoustic oscillations at frequencies of several GHz. PMID:26751616

  9. The Nature of Macular Damage in Glaucoma as Revealed by Averaging Optical Coherence Tomography Data

    PubMed Central

    Hood, Donald C.; Raza, Ali S.; de Moraes, Carlos Gustavo V.; Johnson, Chris A.; Liebmann, Jeffrey M.; Ritch, Robert

    2012-01-01

    Purpose To better understand the nature of glaucomatous damage, especially to the macula, the inner retinal thickness maps obtained with frequency domain optical coherence tomography (fdOCT) were averaged. Methods Frequency domain optical coherence tomography macular and optic disc cube scans were obtained from 54 healthy eyes and 156 eyes with glaucomatous optic neuropathy. A manually corrected algorithm was used for layer segmentation. Patients' eyes were grouped both by mean deviation (MD) and hemifield classification using standard categories and 24-2 (6° grid) visual fields (VFs). To obtain average difference maps, the thickness of retinal nerve fiber (RNF) and retinal ganglion cell plus inner plexiform (RGC+) layers were averaged and subtracted from the average control values. Results On the average difference maps, RGC+ and RNF layer thinning was seen in the patient groups with VFs classified as normal. The pattern of the thinning was the same, but the degree of thinning increased with decreased MD and with classification category (from normal to arcuate). This RGC+ thinning was largely within the central four points of the 24-2 (6° grid) field, after correcting for RGC displacement. Conclusion 1. VF categories represent different degrees of the same pattern of RGC+ and RNFL layer thinning. 2. RGC+ damage occurs in the central macula even in patients with VFs classified as normal. 3. The 6° grid (24-2) pattern is not optimally designed to detect macular damage. 4. A schematic model of RGC projections is proposed to explain the pattern of macular loss, including the greater vulnerability of the inferior retinal region. Translational relevance The 24-2 is not an optimal test pattern for detecting or following glaucomatous damage. Further, we suggest clinical fdOCT reports include RGC+ and RNFL probability plots combined with VF information. PMID:23626924

  10. Revealing long-range interconnected hubs in human chromatin interaction data using graph theory.

    PubMed

    Boulos, R E; Arneodo, A; Jensen, P; Audit, B

    2013-09-13

    We use graph theory to analyze chromatin interaction (Hi-C) data in the human genome. We show that a key functional feature of the genome--"master" replication origins--corresponds to DNA loci of maximal network centrality. These loci form a set of interconnected hubs both within chromosomes and between different chromosomes. Our results open the way to a fruitful use of graph theory concepts to decipher DNA structural organization in relation to genome functions such as replication and transcription. This quantitative information should prove useful to discriminate between possible polymer models of nuclear organization.

  11. Revealing Long-Range Interconnected Hubs in Human Chromatin Interaction Data Using Graph Theory

    NASA Astrophysics Data System (ADS)

    Boulos, R. E.; Arneodo, A.; Jensen, P.; Audit, B.

    2013-09-01

    We use graph theory to analyze chromatin interaction (Hi-C) data in the human genome. We show that a key functional feature of the genome—“master” replication origins—corresponds to DNA loci of maximal network centrality. These loci form a set of interconnected hubs both within chromosomes and between different chromosomes. Our results open the way to a fruitful use of graph theory concepts to decipher DNA structural organization in relation to genome functions such as replication and transcription. This quantitative information should prove useful to discriminate between possible polymer models of nuclear organization.

  12. Long-range evolutionary constraints reveal cis-regulatory interactions on the human X chromosome

    PubMed Central

    Naville, Magali; Ishibashi, Minaka; Ferg, Marco; Bengani, Hemant; Rinkwitz, Silke; Krecsmarik, Monika; Hawkins, Thomas A.; Wilson, Stephen W.; Manning, Elizabeth; Chilamakuri, Chandra S. R.; Wilson, David I.; Louis, Alexandra; Lucy Raymond, F.; Rastegar, Sepand; Strähle, Uwe; Lenhard, Boris; Bally-Cuif, Laure; van Heyningen, Veronica; FitzPatrick, David R.; Becker, Thomas S.; Roest Crollius, Hugues

    2015-01-01

    Enhancers can regulate the transcription of genes over long genomic distances. This is thought to lead to selection against genomic rearrangements within such regions that may disrupt this functional linkage. Here we test this concept experimentally using the human X chromosome. We describe a scoring method to identify evolutionary maintenance of linkage between conserved noncoding elements and neighbouring genes. Chromatin marks associated with enhancer function are strongly correlated with this linkage score. We test >1,000 putative enhancers by transgenesis assays in zebrafish to ascertain the identity of the target gene. The majority of active enhancers drive a transgenic expression in a pattern consistent with the known expression of a linked gene. These results show that evolutionary maintenance of linkage is a reliable predictor of an enhancer's function, and provide new information to discover the genetic basis of diseases caused by the mis-regulation of gene expression. PMID:25908307

  13. Comprehensive mapping of long-range interactions reveals folding principles of the human genome.

    PubMed

    Lieberman-Aiden, Erez; van Berkum, Nynke L; Williams, Louise; Imakaev, Maxim; Ragoczy, Tobias; Telling, Agnes; Amit, Ido; Lajoie, Bryan R; Sabo, Peter J; Dorschner, Michael O; Sandstrom, Richard; Bernstein, Bradley; Bender, M A; Groudine, Mark; Gnirke, Andreas; Stamatoyannopoulos, John; Mirny, Leonid A; Lander, Eric S; Dekker, Job

    2009-10-09

    We describe Hi-C, a method that probes the three-dimensional architecture of whole genomes by coupling proximity-based ligation with massively parallel sequencing. We constructed spatial proximity maps of the human genome with Hi-C at a resolution of 1 megabase. These maps confirm the presence of chromosome territories and the spatial proximity of small, gene-rich chromosomes. We identified an additional level of genome organization that is characterized by the spatial segregation of open and closed chromatin to form two genome-wide compartments. At the megabase scale, the chromatin conformation is consistent with a fractal globule, a knot-free, polymer conformation that enables maximally dense packing while preserving the ability to easily fold and unfold any genomic locus. The fractal globule is distinct from the more commonly used globular equilibrium model. Our results demonstrate the power of Hi-C to map the dynamic conformations of whole genomes.

  14. Protein adsorption on tailored substrates: long-range forces and conformational changes

    NASA Astrophysics Data System (ADS)

    Bellion, M.; Santen, L.; Mantz, H.; Hähl, H.; Quinn, A.; Nagel, A.; Gilow, C.; Weitenberg, C.; Schmitt, Y.; Jacobs, K.

    2008-10-01

    Adsorption of proteins onto solid surfaces is an everyday phenomenon that is not yet fully understood. To further the current understanding, we have performed in situ ellipsometry studies to reveal the adsorption kinetics of three different proteins, lysozyme, α-amylase and bovine serum albumin. As substrates we offer Si wafers with a controlled Si oxide layer thickness and a hydrophilic or hydrophobic surface functionalization, allowing the tailoring of the influence of short- and long-range interactions. Our studies show that not only the surface chemistry determines the properties of an adsorbed protein layer but also the van der Waals contributions of a composite substrate. We compare the experimental findings to results of a colloidal Monte Carlo approach that includes conformational changes of the adsorbed proteins induced by density fluctuations.

  15. Measuring long-range carrier diffusion across multiple grains in polycrystalline semiconductors by photoluminescence imaging

    PubMed Central

    Alberi, K.; Fluegel, B.; Moutinho, H.; Dhere, R. G.; Li, J. V.; Mascarenhas, A.

    2013-01-01

    Thin-film polycrystalline semiconductors are currently at the forefront of inexpensive large-area solar cell and integrated circuit technologies because of their reduced processing and substrate selection constraints. Understanding the extent to which structural and electronic defects influence carrier transport in these materials is critical to controlling the optoelectronic properties, yet many measurement techniques are only capable of indirectly probing their effects. Here we apply a novel photoluminescence imaging technique to directly observe the low temperature diffusion of photocarriers through and across defect states in polycrystalline CdTe thin films. Our measurements show that an inhomogeneous distribution of localized defect states mediates long-range hole transport across multiple grain boundaries to locations exceeding 10 μm from the point of photogeneration. These results provide new insight into the key role deep trap states have in low temperature carrier transport in polycrystalline CdTe by revealing their propensity to act as networks for hopping conduction. PMID:24158163

  16. Long range transported pollutants and conductivity of atmospheric ice on insulators

    SciTech Connect

    Fikke, S.M. ); Hanssen, J.E. ); Rolfseng, L. )

    1993-07-01

    Internationally comprehensive studies have been performed to analyze the effect of clean or contaminated snow and ice accretions on high voltage insulators. The experience with transmission lines in inland mountainous areas reveals a substantial contribution of pollution from anthropogenic (man made) contaminants. One observation of a flash over case with thin rime ice layers in contrast to the many cases with thicker accretions without similar failures, led to the question of the role of the ion content of the ice. 55 ice samples are analyzed and the contributions to the conductivity from natural (sea salt) and man made ions (sulphur and nitrogen components) are found. It is shown that long range transported anthropogenic ions contributed to more than 50% of the conductivity in 33 of the 55 cases, and in 21 cases the contribution was more than 80%.

  17. Measuring long-range carrier diffusion across multiple grains in polycrystalline semiconductors by photoluminescence imaging.

    PubMed

    Alberi, K; Fluegel, B; Moutinho, H; Dhere, R G; Li, J V; Mascarenhas, A

    2013-01-01

    Thin-film polycrystalline semiconductors are currently at the forefront of inexpensive large-area solar cell and integrated circuit technologies because of their reduced processing and substrate selection constraints. Understanding the extent to which structural and electronic defects influence carrier transport in these materials is critical to controlling the optoelectronic properties, yet many measurement techniques are only capable of indirectly probing their effects. Here we apply a novel photoluminescence imaging technique to directly observe the low temperature diffusion of photocarriers through and across defect states in polycrystalline CdTe thin films. Our measurements show that an inhomogeneous distribution of localized defect states mediates long-range hole transport across multiple grain boundaries to locations exceeding 10 μm from the point of photogeneration. These results provide new insight into the key role deep trap states have in low temperature carrier transport in polycrystalline CdTe by revealing their propensity to act as networks for hopping conduction.

  18. Measuring long-range carrier diffusion across multiple grains in polycrystalline semiconductors by photoluminescence imaging

    NASA Astrophysics Data System (ADS)

    Alberi, K.; Fluegel, B.; Moutinho, H.; Dhere, R. G.; Li, J. V.; Mascarenhas, A.

    2013-10-01

    Thin-film polycrystalline semiconductors are currently at the forefront of inexpensive large-area solar cell and integrated circuit technologies because of their reduced processing and substrate selection constraints. Understanding the extent to which structural and electronic defects influence carrier transport in these materials is critical to controlling the optoelectronic properties, yet many measurement techniques are only capable of indirectly probing their effects. Here we apply a novel photoluminescence imaging technique to directly observe the low temperature diffusion of photocarriers through and across defect states in polycrystalline CdTe thin films. Our measurements show that an inhomogeneous distribution of localized defect states mediates long-range hole transport across multiple grain boundaries to locations exceeding 10 μm from the point of photogeneration. These results provide new insight into the key role deep trap states have in low temperature carrier transport in polycrystalline CdTe by revealing their propensity to act as networks for hopping conduction.

  19. Uncertainty quantification of environmental performance metrics in heterogeneous aquifers with long-range correlations

    NASA Astrophysics Data System (ADS)

    Moslehi, Mahsa; de Barros, Felipe P. J.

    2017-01-01

    We investigate how the uncertainty stemming from disordered porous media that display long-range correlation in the hydraulic conductivity (K) field propagates to predictions of environmental performance metrics (EPMs). In this study, the EPMs are quantities that are of relevance to risk analysis and remediation, such as peak flux-averaged concentration, early and late arrival times among others. By using stochastic simulations, we quantify the uncertainty associated with the EPMs for a given disordered spatial structure of the K-field and identify the probability distribution function (PDF) model that best captures the statistics of the EPMs of interest. Results indicate that the probabilistic distribution of the EPMs considered in this study follows lognormal PDF. Finally, through the use of information theory, we reveal how the persistent/anti-persistent correlation structure of the K-field influences the EPMs and corresponding uncertainties.

  20. Long-range structural order, moiré patterns, and iridescence in latex-stabilized foams.

    PubMed

    Fujii, Syuji; Ryan, Anthony J; Armes, Steven P

    2006-06-21

    We describe the facile production of highly stable foams stabilized solely by micrometer-sized, sterically stabilized polystyrene (PS) latex particles. Such foams can survive for more than one year in the wet state and remain intact after drying. In contrast, foams stabilized with either sodium dodecyl sulfate or poly(N-vinylpyrrolidone) were destroyed after removal of the aqueous phase. Scanning electron microscopy studies reveal hexagonally close-packed arrays of PS particles within the dried foam, which suggests high colloid stability for the PS particles prior to their adsorption at the air-water interface. Localized moiré patterns are observed by optical microscopy due to the formation of well-defined latex bilayers with exquisite long-range order. Moreover, the dried foams are highly iridescent in bright transmitted light, which may offer potential applications in security inks and coatings.

  1. Uncertainty quantification of environmental performance metrics in heterogeneous aquifers with long-range correlations.

    PubMed

    Moslehi, Mahsa; de Barros, Felipe P J

    2017-01-01

    We investigate how the uncertainty stemming from disordered porous media that display long-range correlation in the hydraulic conductivity (K) field propagates to predictions of environmental performance metrics (EPMs). In this study, the EPMs are quantities that are of relevance to risk analysis and remediation, such as peak flux-averaged concentration, early and late arrival times among others. By using stochastic simulations, we quantify the uncertainty associated with the EPMs for a given disordered spatial structure of the K-field and identify the probability distribution function (PDF) model that best captures the statistics of the EPMs of interest. Results indicate that the probabilistic distribution of the EPMs considered in this study follows lognormal PDF. Finally, through the use of information theory, we reveal how the persistent/anti-persistent correlation structure of the K-field influences the EPMs and corresponding uncertainties.

  2. Viability assessment of bacteria using long-range surface plasmon waveguide biosensors

    NASA Astrophysics Data System (ADS)

    Béland, Paul; Berini, Pierre

    2017-01-01

    We demonstrate that long-range surface plasmon waveguide biosensors are useful to monitor the quiver of immobilized live bacteria in buffer and in human urine. First, the biosensor captures bacteria selectively, based on gram, using antibodies against gram adsorbed on the surface of the waveguide through Protein G coupling. Then, analysis of the noise present on the optical output signal reveals quiver of bacteria immobilized on the waveguide. Live bacteria produce a noisy signature compared to baseline levels. The standard deviation over time of the optical power output from the biosensor increased by factors of 3-60 over that of the baseline level for Staphylococcus epidermidis and Escherichia coli immobilized selectively on waveguides.

  3. Breakdown of long-range temporal dependence in default mode and attention networks during deep sleep

    PubMed Central

    Tagliazucchi, Enzo; von Wegner, Frederic; Morzelewski, Astrid; Brodbeck, Verena; Jahnke, Kolja; Laufs, Helmut

    2013-01-01

    The integration of segregated brain functional modules is a prerequisite for conscious awareness during wakeful rest. Here, we test the hypothesis that temporal integration, measured as long-term memory in the history of neural activity, is another important quality underlying conscious awareness. For this aim, we study the temporal memory of blood oxygen level-dependent signals across the human nonrapid eye movement sleep cycle. Results reveal that this property gradually decreases from wakefulness to deep nonrapid eye movement sleep and that such decreases affect areas identified with default mode and attention networks. Although blood oxygen level-dependent spontaneous fluctuations exhibit nontrivial spatial organization, even during deep sleep, they also display a decreased temporal complexity in specific brain regions. Conversely, this result suggests that long-range temporal dependence might be an attribute of the spontaneous conscious mentation performed during wakeful rest. PMID:24003146

  4. Effect of Synaptic Connectivity on Long-Range Synchronization of Fast Cortical Oscillations

    PubMed Central

    Bazhenov, M.; Rulkov, N. F.; Timofeev, I.

    2008-01-01

    Cortical gamma oscillations in the 20- to 80-Hz range are associated with attentiveness and sensory perception and have strong connections to both cognitive processing and temporal binding of sensory stimuli. These gamma oscillations become synchronized within a few milliseconds over distances spanning a few millimeters in spite of synaptic delays. In this study using in vivo recordings and large-scale cortical network models, we reveal a critical role played by the network geometry in achieving precise long-range synchronization in the gamma frequency band. Our results indicate that the presence of many independent synaptic pathways in a two-dimensional network facilitate precise phase synchronization of fast gamma band oscillations with nearly zero phase delays between remote network sites. These findings predict a common mechanism of precise oscillatory synchronization in neuronal networks. PMID:18632897

  5. A Statistical Multimodel Ensemble Approach to Improving Long-Range Forecasting in Pakistan

    DTIC Science & Technology

    2012-03-01

    MULTIMODEL ENSEMBLE APPROACH TO IMPROVING LONG-RANGE FORECASTING IN PAKISTAN by Shane D. Gillies March 2012 Thesis Co-Advisors: Tom Murphree...DATES COVERED Master’s Thesis 4. TITLE AND SUBTITLE A Statistical Multimodel Ensemble Approach to Improving Long-Range Forecasting in Pakistan 5...was selected based on DoD and national intelligence priorities for long-range support. For this test case, the system uses 81 ensemble forecast

  6. Cell-type-specific long-range looping interactions identify distant regulatory elements of the CFTR gene

    PubMed Central

    Gheldof, Nele; Smith, Emily M.; Tabuchi, Tomoko M.; Koch, Christoph M.; Dunham, Ian; Stamatoyannopoulos, John A.; Dekker, Job

    2010-01-01

    Identification of regulatory elements and their target genes is complicated by the fact that regulatory elements can act over large genomic distances. Identification of long-range acting elements is particularly important in the case of disease genes as mutations in these elements can result in human disease. It is becoming increasingly clear that long-range control of gene expression is facilitated by chromatin looping interactions. These interactions can be detected by chromosome conformation capture (3C). Here, we employed 3C as a discovery tool for identification of long-range regulatory elements that control the cystic fibrosis transmembrane conductance regulator gene, CFTR. We identified four elements in a 460-kb region around the locus that loop specifically to the CFTR promoter exclusively in CFTR expressing cells. The elements are located 20 and 80 kb upstream; and 109 and 203 kb downstream of the CFTR promoter. These elements contain DNase I hypersensitive sites and histone modification patterns characteristic of enhancers. The elements also interact with each other and the latter two activate the CFTR promoter synergistically in reporter assays. Our results reveal novel long-range acting elements that control expression of CFTR and suggest that 3C-based approaches can be used for discovery of novel regulatory elements. PMID:20360044

  7. Satellite measurements reveal strong anisotropy in spatial coherence of climate variations over the Tibet Plateau.

    PubMed

    Chen, Deliang; Tian, Yudong; Yao, Tandong; Ou, Tinghai

    2016-08-24

    This study uses high-resolution, long-term satellite observations to evaluate the spatial scales of the climate variations across the Tibet Plateau (TP). Both land surface temperature and precipitation observations of more than 10 years were analysed with a special attention to eight existing ice-core sites in the TP. The temporal correlation for the monthly or annual anomalies between any two points decreases exponentially with their spatial distance, and we used the e-folding decay constant to quantify the spatial scales. We found that the spatial scales are strongly direction-dependent, with distinctive patterns in the west-east and south-north orientations, for example. Meanwhile, in the same directions the scales are largely symmetric backward and forward. Focusing on the west-east and south-north directions, we found the spatial coherence in the first is generally stronger than in the second. The annual surface temperature had typical spatial scales of 302-480 km, while the annual precipitation showed smaller scales of 111-182 km. The majority of the eight ice-core sites exhibit scales much smaller than the typical scales over the TP as a whole. These results provide important observational basis for the selection of appropriate downscaling strategies, deployment of climate-data collection networks, and interpreting paleoclimate reconstructions.

  8. Arrhythmia Caused by a Drosophila Tropomyosin Mutation Is Revealed Using a Novel Optical Coherence Tomography Instrument

    PubMed Central

    Ma, Lisha; Bradu, Adrian; Podoleanu, Adrian Gh.; Bloor, James W.

    2010-01-01

    Background Dilated cardiomyopathy (DCM) is a severe cardiac condition that causes high mortality. Many genes have been confirmed to be involved in this disease. An ideal system with which to uncover disease mechanisms would be one that can measure the changes in a wide range of cardiac activities associated with mutations in specific, diversely functional cardiac genes. Such a system needs a genetically manipulable model organism that allows in vivo measurement of cardiac phenotypes and a detecting instrument capable of recording multiple phenotype parameters. Methodology and Principal Findings With a simple heart, a transparent body surface at larval stages and available genetic tools we chose Drosophila melanogaster as our model organism and developed for it a dual en-face/Doppler optical coherence tomography (OCT) instrument capable of recording multiple aspects of heart activity, including heart contraction cycle dynamics, ostia dynamics, heartbeat rate and rhythm, speed of heart wall movement and light reflectivity of cardiomyocytes in situ. We applied this OCT instrument to a model of Tropomyosin-associated DCM established in adult Drosophila. We show that DCM pre-exists in the larval stage and is accompanied by an arrhythmia previously unidentified in this model. We also detect reduced mobility and light reflectivity of cardiomyocytes in mutants. Conclusion These results demonstrate the capability of our OCT instrument to characterize in detail cardiac activity in genetic models for heart disease in Drosophila. PMID:21179409

  9. Simulating 2,368 temperate lakes reveals weak coherence in stratification phenology

    USGS Publications Warehouse

    Read, Jordan S.; Winslow, Luke A.; Hansen, Gretchen J. A.; Van Den Hoek, Jamon; Hanson, Paul C.; Bruce, Louise C; Markfort, Corey D.

    2014-01-01

    Changes in water temperatures resulting from climate warming can alter the structure and function of aquatic ecosystems. Lake-specific physical characteristics may play a role in mediating individual lake responses to climate. Past mechanistic studies of lake-climate interactions have simulated generic lake classes at large spatial scales or performed detailed analyses of small numbers of real lakes. Understanding the diversity of lake responses to climate change across landscapes requires a hybrid approach that couples site-specific lake characteristics with broad-scale environmental drivers. This study provides a substantial advancement in lake ecosystem modeling by combining open-source tools with freely available continental-scale data to mechanistically model daily temperatures for 2,368 Wisconsin lakes over three decades (1979-2011). The model accurately predicted observed surface layer temperatures (RMSE: 1.74°C) and the presence/absence of stratification (81.1% agreement). Among-lake coherence was strong for surface temperatures and weak for the timing of stratification, suggesting individual lake characteristics mediate some - but not all - ecologically relevant lake responses to climate.

  10. Optical Coherence Tomography angiography reveals laminar microvascular hemodynamics in the rat somatosensory cortex during activation.

    PubMed

    Srinivasan, Vivek J; Radhakrishnan, Harsha

    2014-11-15

    The BOLD (blood-oxygen-level dependent) fMRI (functional Magnetic Resonance Imaging) signal is shaped, in part, by changes in red blood cell (RBC) content and flow across vascular compartments over time. These complex dynamics have been challenging to characterize directly due to a lack of appropriate imaging modalities. In this study, making use of infrared light scattering from RBCs, depth-resolved Optical Coherence Tomography (OCT) angiography was applied to image laminar functional hyperemia in the rat somatosensory cortex. After defining and validating depth-specific metrics for changes in RBC content and speed, laminar hemodynamic responses in microvasculature up to cortical depths of >1mm were measured during a forepaw stimulus. The results provide a comprehensive picture of when and where changes in RBC content and speed occur during and immediately following cortical activation. In summary, the earliest and largest microvascular RBC content changes occurred in the middle cortical layers, while post-stimulus undershoots were most prominent superficially. These laminar variations in positive and negative responses paralleled known distributions of excitatory and inhibitory synapses, suggesting neuronal underpinnings. Additionally, the RBC speed response consistently returned to baseline more promptly than RBC content after the stimulus across cortical layers, supporting a "flow-volume mismatch" of hemodynamic origin.

  11. Satellite measurements reveal strong anisotropy in spatial coherence of climate variations over the Tibet Plateau

    PubMed Central

    Chen, Deliang; Tian, Yudong; Yao, Tandong; Ou, Tinghai

    2016-01-01

    This study uses high-resolution, long-term satellite observations to evaluate the spatial scales of the climate variations across the Tibet Plateau (TP). Both land surface temperature and precipitation observations of more than 10 years were analysed with a special attention to eight existing ice-core sites in the TP. The temporal correlation for the monthly or annual anomalies between any two points decreases exponentially with their spatial distance, and we used the e-folding decay constant to quantify the spatial scales. We found that the spatial scales are strongly direction-dependent, with distinctive patterns in the west-east and south-north orientations, for example. Meanwhile, in the same directions the scales are largely symmetric backward and forward. Focusing on the west-east and south-north directions, we found the spatial coherence in the first is generally stronger than in the second. The annual surface temperature had typical spatial scales of 302–480 km, while the annual precipitation showed smaller scales of 111–182 km. The majority of the eight ice-core sites exhibit scales much smaller than the typical scales over the TP as a whole. These results provide important observational basis for the selection of appropriate downscaling strategies, deployment of climate-data collection networks, and interpreting paleoclimate reconstructions. PMID:27553388

  12. Localized vibrations in superconducting YB a2C u3O7 revealed by ultrafast optical coherent spectroscopy

    NASA Astrophysics Data System (ADS)

    Novelli, Fabio; Giovannetti, Gianluca; Avella, Adolfo; Cilento, Federico; Patthey, Luc; Radovic, Milan; Capone, Massimo; Parmigiani, Fulvio; Fausti, Daniele

    2017-05-01

    The interaction between phonons and high-energy excitations of electronic origin in cuprates and their role in the superconducting mechanisms is still controversial. Here we use coherent vibrational time-domain spectroscopy together with density functional and dynamical mean-field theory calculations to establish a direct link between the c -axis phonon modes and the in-plane electronic charge excitations in optimally doped YB a2C u3O7 . The nonequilibrium Raman tensor is measured by means of the broadband "coherent-phonon" response in pump-probe experiments and is qualitatively described by our model using density functional theory in the frozen-phonon approximation plus single-band dynamical mean-field theory to account for the electronic correlations. The major outcome of our experimental and theoretical study is to establish the link between out-of-plane copper ion displacements and the in-plane electronic correlations, and to estimate at a few unit cells the correlation length of the associated phonon mode. The approach introduced here could help in revealing the complex interplay between fluctuations of different nature and spatial correlation in several strongly correlated materials.

  13. Long-Range Temporal Correlations, Multifractality, and the Causal Relation between Neural Inputs and Movements

    PubMed Central

    Hu, Jing; Zheng, Yi; Gao, Jianbo

    2013-01-01

    Understanding the causal relation between neural inputs and movements is very important for the success of brain-machine interfaces (BMIs). In this study, we analyze 104 neurons’ firings using statistical, information theoretic, and fractal analysis. The latter include Fano factor analysis, multifractal adaptive fractal analysis (MF-AFA), and wavelet multifractal analysis. We find neuronal firings are highly non-stationary, and Fano factor analysis always indicates long-range correlations in neuronal firings, irrespective of whether those firings are correlated with movement trajectory or not, and thus does not reveal any actual correlations between neural inputs and movements. On the other hand, MF-AFA and wavelet multifractal analysis clearly indicate that when neuronal firings are not well correlated with movement trajectory, they do not have or only have weak temporal correlations. When neuronal firings are well correlated with movements, they are characterized by very strong temporal correlations, up to a time scale comparable to the average time between two successive reaching tasks. This suggests that neurons well correlated with hand trajectory experienced a “re-setting” effect at the start of each reaching task, in the sense that within the movement correlated neurons the spike trains’ long-range dependences persisted about the length of time the monkey used to switch between task executions. A new task execution re-sets their activity, making them only weakly correlated with their prior activities on longer time scales. We further discuss the significance of the coalition of those important neurons in executing cortical control of prostheses. PMID:24130549

  14. Enhanced SO2 Concentrations Observed over Northern India: Role of Long-range Transport

    SciTech Connect

    Mallik, C.; Lal, S.; Naja, M.; Chand, Duli; Venkataramani, S.; Joshi, H.; Pant, P.

    2013-01-17

    Volcanic emissions and coal burning are among the major sources of SO2 over the continental environment. In this study, we show episodes of long-range transport of volcanic SO2 from Africa to Northern India using satellite observations. Monthly averaged SO2 from OMI were of the order of 0.6-0.9 DU during November, 2008 over the Indo-Gangetic Plain (IGP), which far exceeded background values (<0.3 DU) retrieved from observations across different locations over North India during 2005-2010. The columnar SO2 loadings were much higher on November 6 over most of the IGP and even exceeded 6 DU, a factor of 10 higher than background levels at some places. These enhanced SO2 levels were, however, not reciprocated in satellite derived NO2 or CO columns, indicating transport from a non-anthropogenic source of SO2. Backward trajectory analysis revealed strong winds in the free troposphere, which originated from the Dalaffilla volcanic eruption over the Afar region of Ethiopia during November 4-6, 2008. Wind streams and stable atmospheric conditions were conducive to the long-range transport of volcanic plume into the IGP. As most of the local aerosols over IGP region are below 3 km, a well separated layer at 4-5 km is observed from CALIPSO, most likely as a result of this transport. Apart from known anthropogenic sources, the additional transport of volcanic SO2 over the IGP region would have implications to air quality and radiation balance over this region.

  15. Long-range transport of volcanic SO2 over Northern India

    NASA Astrophysics Data System (ADS)

    Mallik, Chinmay; Joshi, Hema; Chand, D.; Lal, Shyam; Naja, Manish; Venkataramani, S.; Pant, P.

    2012-07-01

    Anthropogenic activities contribute to more than 70% of global sulfur dioxide (SO2) emissions. Among the natural sources of SO2, volcanic emissions can be significant but sporadic contributors. Apart from releasing a plethora of pollutant gases, volcanoes can also impact atmospheric temperatures and radiation balance as was observed after El Chichon (1982) and Mt. Pinatubo (1991) eruptions. The present study deals with episodes of long-range transport of SO2 from Africa to Northern India using multiple satellite observations. Monthly averaged SO2 from OMI were of the order of 0.6-0.9 DU during November, 2008 over the Indo-Gangetic Plain (IGP). In contrast, SO2 monthly averages retrieved from observations across different locations over North India had never exceeded 0.3 DU during the six year period of 2005-2010. The columnar SO2 loadings were a factor of 10 higher than background levels over most of the IGP on the day of impact. These enhanced SO2 levels were, however, not reciprocated in satellite derived NO2 or CO columns, indicating transport from a non-anthropogenic source of SO2. Back-trajectory analysis revealed strong winds in the free troposphere, which originated from a volcanic eruption over Ethiopia. Wind streams and stable atmospheric conditions were conducive to the long-range transport of volcanic plume over the IGP. Increase in aerosol optical depths were observed both from ground-based measurements as well as satellite observations. A well separated layer of aerosols above the boundary layer was observed from CALIPSO, most likely as a result of this transport. Apart from known anthropogenic sources, the additional transport of volcanic SO2 over the IGP region would have implications to air quality and radiation balance over this region. Details of this episode of transport in terms of meteorology and dynamics will be presented during the assembly.

  16. Color signal integration for color discrimination along a long-range apparent motion trajectory.

    PubMed

    Nagai, Takehiro; Kimura, Hiroto; Nakauchi, Shigeki

    2013-01-01

    In contrast to the classical view that fundamental visual attributes such as color and motion are independently processed in the visual system (e.g. Livingstone and Hubel, 1987; Marr, 1982), recent studies have revealed various forms of cross-attribute interactions, such as averaging of color appearance along the motion trajectory of an object (Nishida et al., 2007). In this study, we investigated whether such color signal integration along a motion trajectory can be induced only by motion mechanisms having large receptive fields, without simple integration within direction-selective neurons with small receptive fields, like those in V1. The stimulus consisted of discs with long-range apparent motion along a circular trajectory. The stimulus onset asynchrony (SOA) between disc presentations controlled the strength of the apparent motion perception. We measured observers' sensitivity in detecting color modulation on the discs. The results showed that the measured sensitivity was lowest at SOAs corresponding to the strongest motion perception. This can be interpreted as follows: color signals were integrated along an apparent motion path, and this integration reduced chromatic sensitivity by averaging color signals. Another experiment that controlled apparent motion perception in a different way also supported this idea. However, this integration effect seemed to be linked to responses of motion detectors for the apparent motion stimuli, not directly to perceptual motion representation in the visual system. These results suggest that the human visual system handles color information from retinal inputs regarding moving objects based not only on a retinotopic coordinate but also on object-based coordinates, even when the moving object yields only long-range apparent motion.

  17. Long range order and two-fluid behavior in heavy electron materials

    DOE PAGES

    Shirer, Kent R.; Shockley, Abigail C.; Dioguardi, Adam P.; ...

    2012-09-24

    The heavy electron Kondo liquid is an emergent state of condensed matter that displays universal behavior independent of material details. Properties of the heavy electron liquid are best probed by NMR Knight shift measurements, which provide a direct measure of the behavior of the heavy electron liquid that emerges below the Kondo lattice coherence temperature as the lattice of local moments hybridizes with the background conduction electrons. Because the transfer of spectral weight between the localized and itinerant electronic degrees of freedom is gradual, the Kondo liquid typically coexists with the local moment component until the material orders at lowmore » temperatures. The two-fluid formula captures this behavior in a broad range of materials in the paramagnetic state. In order to investigate two-fluid behavior and the onset and physical origin of different long range ordered ground states in heavy electron materials, we have extended Knight shift measurements to URu2Si2, CeIrIn5, and CeRhIn5. In CeRhIn5 we find that the antiferromagnetic order is preceded by a relocalization of the Kondo liquid, providing independent evidence for a local moment origin of antiferromagnetism. In URu2Si2 the hidden order is shown to emerge directly from the Kondo liquid and so is not associated with local moment physics. Lastly, our results imply that the nature of the ground state is strongly coupled with the hybridization in the Kondo lattice in agreement with phase diagram proposed by Yang and Pines.« less

  18. Long range order and two-fluid behavior in heavy electron materials

    SciTech Connect

    Shirer, Kent R.; Shockley, Abigail C.; Dioguardi, Adam P.; Crocker, John; Lin, Ching H.; apRoberts-Warren, Nicholas; Nisson, David M.; Klavins, Peter; Cooley, Jason C.; Yang, Yi -feng; Curro, Nicholas J.

    2012-09-24

    The heavy electron Kondo liquid is an emergent state of condensed matter that displays universal behavior independent of material details. Properties of the heavy electron liquid are best probed by NMR Knight shift measurements, which provide a direct measure of the behavior of the heavy electron liquid that emerges below the Kondo lattice coherence temperature as the lattice of local moments hybridizes with the background conduction electrons. Because the transfer of spectral weight between the localized and itinerant electronic degrees of freedom is gradual, the Kondo liquid typically coexists with the local moment component until the material orders at low temperatures. The two-fluid formula captures this behavior in a broad range of materials in the paramagnetic state. In order to investigate two-fluid behavior and the onset and physical origin of different long range ordered ground states in heavy electron materials, we have extended Knight shift measurements to URu2Si2, CeIrIn5, and CeRhIn5. In CeRhIn5 we find that the antiferromagnetic order is preceded by a relocalization of the Kondo liquid, providing independent evidence for a local moment origin of antiferromagnetism. In URu2Si2 the hidden order is shown to emerge directly from the Kondo liquid and so is not associated with local moment physics. Lastly, our results imply that the nature of the ground state is strongly coupled with the hybridization in the Kondo lattice in agreement with phase diagram proposed by Yang and Pines.

  19. Morphology of upper laurentian fan using GLORIA long-range side-scan sonar

    SciTech Connect

    Masson, D.G.; Field, M.E.; Gardner, J.V.; Parson, L.M.

    1985-06-01

    A long-range side-scan sonar (GLORIA) survey of the upper Laurentian Fan shows, for the first time, the regional geomorphology of this large and complex sedimentary body. The channels of the upper continental slope coalesce on the upper fan to form four major fan valleys. The largest of these, Eastern Valley, is U-shaped in cross section and up to 25 km (15 mi) wide with a large levee on the western flank that reaches a maximum height of more than 1 km (3,300 ft) above the valley floor. The remaining valleys, Western, Central, and Grand Banks, are typically more V-shaped in cross section and are up to 5 km (3 mi) wide. Extensive gullying is observed on the walls of all the channels. Sonographs of the floor of Eastern Valley show a strong, linear fabric elongated parallel with the valley walls that appears to be related to mesoscale relief on the valley floor. At water depths between 3,500 and 4,100 m (11,550 and 13,530 ft), two major fan valleys are created by the merging of the four major valleys of the upper fan. Both fan valleys are associated with large, asymmetric levee complexes that reach heights of more than 500 m (1,650 ft) above the valley floors. The GLORIA data show evidence for several amphitheaterlike slump scars in the region of the 1929 earthquake epicenter. However, the authors see no evidence for movement of large coherent sediment blocks as postulated by earlier workers. They suggest that the turbidity currents that occurred after the 1929 earthquake may have formed by the coalescence of many small slumps rather than from a single large slump.

  20. Long-range magnetic ordering in a metal-organic framework based on octanuclear nickel(ii) clusters.

    PubMed

    Wang, Jun-Li; Bai, Yan; Pan, Hui; Zheng, Guang-Shui; Dang, Dong-Bin

    2017-09-19

    A novel three-dimensional metal-organic framework [Ni3(BTC)2(bpp)2(H2O)]·3H2O (1) based on mixed ligands H3BTC (1,2,4-benzenetricarboxylic acid) and bpp (1,3-bis(4-pyridyl)propane) was obtained under hydrothermal conditions. Crystal structure analysis reveals that 1 is a framework based on cage-like Ni8(COO)12 units. Furthermore, long-range magnetic ordering is observed at low temperature.

  1. Water quality and daily temperature cycle affect biofilm formation in drip irrigation devices revealed by optical coherence tomography.

    PubMed

    Qian, Jueying; Horn, Harald; Tarchitzky, Jorge; Chen, Yona; Katz, Sagi; Wagner, Michael

    2017-03-01

    Drip irrigation is a water-saving technology. To date, little is known about how biofilm forms in drippers of irrigation systems. In this study, the internal dripper geometry was recreated in 3-D printed microfluidic devices (MFDs). To mimic the temperature conditions in (semi-) arid areas, experiments were conducted in a temperature controlled box between 20 and 50°C. MFDs were either fed with two different treated wastewater (TWW) or synthetic wastewater. Biofilm formation was monitored non-invasively and in situ by optical coherence tomography (OCT). 3-D OCT datasets reveal the major fouling position and illustrate that biofilm development was influenced by fluid dynamics. Biofilm volumetric coverage of the labyrinth up to 60% did not reduce the discharge rate, whereas a further increase to 80% reduced the discharge rate by 50%. Moreover, the biofilm formation rate was significantly inhibited in daily temperature cycle independent of the cultivation medium used.

  2. Create Ownership in Your Long Range Plan with a Technology Audit.

    ERIC Educational Resources Information Center

    Biggs, Phil

    1988-01-01

    Discussion of group dynamics and long range planning focuses on a technology audit conducted to help determine a long range plan for computer use in the Rangley, Colorado, public schools. Planning strategies are explained, survey questions are presented, and the actual audit process and trends that emerged from it are described. (LRW)

  3. North Idaho College Long-Range Plan and Statement of Institutional Mission and Purpose.

    ERIC Educational Resources Information Center

    Cargol, Owen F.

    Based upon a planning project initiated at North Idaho College (NIC) in 1981 and approved by the Board of Trustees in 1982, this long-range plan states the mission of NIC and specifies goals and objectives to be attained in the next 3 years. First, introductory sections consider the qualities of a good long-range plan, address the responsibilities…

  4. 75 FR 1799 - Terminate Long Range Aids to Navigation (Loran-C) Signal

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-13

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF HOMELAND SECURITY Coast Guard Terminate Long Range Aids to Navigation (Loran-C) Signal AGENCY: U.S. Coast Guard, DHS... Register of January 7, 2010 (75 FR 998). The document announced termination of the Long Range Aids...

  5. 14 CFR 125.267 - Flight navigator and long-range navigation equipment.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Flight navigator and long-range navigation... Requirements § 125.267 Flight navigator and long-range navigation equipment. (a) No certificate holder may...-range means of navigation which enable a reliable determination to be made of the position of...

  6. College of DuPage Long Range Financial Plans, 1993 through 1997.

    ERIC Educational Resources Information Center

    College of DuPage, Glen Ellyn, IL.

    In 1992, a study was conducted to create a framework allowing administrators at the College of DuPage (CD) in Illinois to examine the long-range implications of financial decisions. The CD long-range financial plans consist of the following components: operating funds; construction funds; tax funds; auxiliary enterprise funds; and non-grant…

  7. 48 CFR 5.404 - Release of long-range acquisition estimates.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Release of long-range acquisition estimates. 5.404 Section 5.404 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION ACQUISITION PLANNING PUBLICIZING CONTRACT ACTIONS Release of Information 5.404 Release of long-range acquisition estimates. To assist...

  8. 48 CFR 5.404-2 - Announcements of long-range acquisition estimates.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Announcements of long-range acquisition estimates. 5.404-2 Section 5.404-2 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION ACQUISITION PLANNING PUBLICIZING CONTRACT ACTIONS Release of Information 5.404-2 Announcements of long-range acquisition estimates...

  9. 48 CFR 1305.404 - Release of long-range acquisition estimates.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Release of long-range acquisition estimates. 1305.404 Section 1305.404 Federal Acquisition Regulations System DEPARTMENT OF COMMERCE COMPETITION AND ACQUISITION PLANNING PUBLICIZING CONTRACT ACTIONS Release of Information 1305.404 Release of long-range acquisition estimates...

  10. 48 CFR 1405.404 - Release of long-range acquisition estimates.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Release of long-range acquisition estimates. 1405.404 Section 1405.404 Federal Acquisition Regulations System DEPARTMENT OF THE INTERIOR COMPETITION AND ACQUISITION PLANNING PUBLICIZING CONTRACT ACTIONS Release of Information 1405.404 Release of long-range acquisition...

  11. 48 CFR 605.404 - Release of long-range acquisition estimates.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false Release of long-range acquisition estimates. 605.404 Section 605.404 Federal Acquisition Regulations System DEPARTMENT OF STATE COMPETITION AND ACQUISITION PLANNING PUBLICIZING CONTRACT ACTIONS Release of Information 605.404 Release of long-range acquisition estimates...

  12. 48 CFR 405.404 - Release of long-range acquisition estimates.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false Release of long-range acquisition estimates. 405.404 Section 405.404 Federal Acquisition Regulations System DEPARTMENT OF AGRICULTURE COMPETITION AND ACQUISITION PLANNING PUBLICIZING CONTRACT ACTIONS Release of Information 405.404 Release of long-range acquisition estimates...

  13. College of DuPage Long Range Financial Plans, 1993 through 1997.

    ERIC Educational Resources Information Center

    College of DuPage, Glen Ellyn, IL.

    In 1992, a study was conducted to create a framework allowing administrators at the College of DuPage (CD) in Illinois to examine the long-range implications of financial decisions. The CD long-range financial plans consist of the following components: operating funds; construction funds; tax funds; auxiliary enterprise funds; and non-grant…

  14. The third stage of hospital long-range planning: the marketing approach.

    PubMed

    Rynne, T J

    1980-01-01

    Today most hospital administrators are convinced they should implement long-range planning. The marketing approach to long-range planning is an effective strategy that is consumer oriented. It starts the planning process with the consumer, letting the consumer's needs and wants guide the organization's planning.

  15. North Idaho College Long-Range Plan and Statement of Institutional Mission and Purpose.

    ERIC Educational Resources Information Center

    Cargol, Owen F.

    Based upon a planning project initiated at North Idaho College (NIC) in 1981 and approved by the Board of Trustees in 1982, this long-range plan states the mission of NIC and specifies goals and objectives to be attained in the next 3 years. First, introductory sections consider the qualities of a good long-range plan, address the responsibilities…

  16. Climate Analysis and Long Range Forecasting of Radar Performance in the Western North Pacific

    DTIC Science & Technology

    2009-06-01

    LONG RANGE FORECASTING OF RADAR PERFORMANCE IN THE WESTERN NORTH PACIFIC by David Ramsaur June 2009 Thesis Co-Advisors...2. REPORT DATE June 2009 3. REPORT TYPE AND DATES COVERED Master’s Thesis 4. TITLE AND SUBTITLE Climate Analysis and Long Range...degree of MASTER OF SCIENCE IN METEOROLOGY from the NAVAL POSTGRADUATE SCHOOL June 2009 Author: David C. Ramsaur

  17. 48 CFR 1305.404 - Release of long-range acquisition estimates.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 5 2013-10-01 2013-10-01 false Release of long-range acquisition estimates. 1305.404 Section 1305.404 Federal Acquisition Regulations System DEPARTMENT OF COMMERCE... long-range acquisition estimates....

  18. 48 CFR 405.404 - Release of long-range acquisition estimates.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 4 2011-10-01 2011-10-01 false Release of long-range acquisition estimates. 405.404 Section 405.404 Federal Acquisition Regulations System DEPARTMENT OF... Release of long-range acquisition estimates....

  19. 48 CFR 5.404-2 - Announcements of long-range acquisition estimates.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...-range acquisition estimates. 5.404-2 Section 5.404-2 Federal Acquisition Regulations System FEDERAL... Announcements of long-range acquisition estimates. Further publicizing, consistent with the needs of the individual case, may be accomplished by announcing through the GPE that long-range acquisition estimates...

  20. 48 CFR 1405.404 - Release of long-range acquisition estimates.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 5 2012-10-01 2012-10-01 false Release of long-range acquisition estimates. 1405.404 Section 1405.404 Federal Acquisition Regulations System DEPARTMENT OF THE... Release of long-range acquisition estimates....

  1. 48 CFR 1305.404 - Release of long-range acquisition estimates.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 5 2011-10-01 2011-10-01 false Release of long-range acquisition estimates. 1305.404 Section 1305.404 Federal Acquisition Regulations System DEPARTMENT OF COMMERCE... long-range acquisition estimates....

  2. 48 CFR 5.404-2 - Announcements of long-range acquisition estimates.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...-range acquisition estimates. 5.404-2 Section 5.404-2 Federal Acquisition Regulations System FEDERAL... Announcements of long-range acquisition estimates. Further publicizing, consistent with the needs of the individual case, may be accomplished by announcing through the GPE that long-range acquisition estimates...

  3. 48 CFR 1405.404 - Release of long-range acquisition estimates.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 5 2013-10-01 2013-10-01 false Release of long-range acquisition estimates. 1405.404 Section 1405.404 Federal Acquisition Regulations System DEPARTMENT OF THE... Release of long-range acquisition estimates....

  4. 48 CFR 605.404 - Release of long-range acquisition estimates.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 4 2012-10-01 2012-10-01 false Release of long-range acquisition estimates. 605.404 Section 605.404 Federal Acquisition Regulations System DEPARTMENT OF STATE... long-range acquisition estimates....

  5. 48 CFR 5.404 - Release of long-range acquisition estimates.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 1 2011-10-01 2011-10-01 false Release of long-range...-range acquisition estimates. To assist industry planning and to locate additional sources of supply, it may be desirable to publicize estimates of unclassified long-range acquisition requirements....

  6. 48 CFR 1405.404 - Release of long-range acquisition estimates.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 5 2014-10-01 2014-10-01 false Release of long-range acquisition estimates. 1405.404 Section 1405.404 Federal Acquisition Regulations System DEPARTMENT OF THE... Release of long-range acquisition estimates....

  7. 48 CFR 405.404 - Release of long-range acquisition estimates.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 4 2014-10-01 2014-10-01 false Release of long-range acquisition estimates. 405.404 Section 405.404 Federal Acquisition Regulations System DEPARTMENT OF... Release of long-range acquisition estimates....

  8. 48 CFR 5.404 - Release of long-range acquisition estimates.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 1 2014-10-01 2014-10-01 false Release of long-range...-range acquisition estimates. To assist industry planning and to locate additional sources of supply, it may be desirable to publicize estimates of unclassified long-range acquisition requirements....

  9. 48 CFR 605.404 - Release of long-range acquisition estimates.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 4 2014-10-01 2014-10-01 false Release of long-range acquisition estimates. 605.404 Section 605.404 Federal Acquisition Regulations System DEPARTMENT OF STATE... long-range acquisition estimates....

  10. 48 CFR 1405.404 - Release of long-range acquisition estimates.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 5 2011-10-01 2011-10-01 false Release of long-range acquisition estimates. 1405.404 Section 1405.404 Federal Acquisition Regulations System DEPARTMENT OF THE... Release of long-range acquisition estimates....

  11. 48 CFR 405.404 - Release of long-range acquisition estimates.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 4 2013-10-01 2013-10-01 false Release of long-range acquisition estimates. 405.404 Section 405.404 Federal Acquisition Regulations System DEPARTMENT OF... Release of long-range acquisition estimates....

  12. 48 CFR 605.404 - Release of long-range acquisition estimates.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 4 2013-10-01 2013-10-01 false Release of long-range acquisition estimates. 605.404 Section 605.404 Federal Acquisition Regulations System DEPARTMENT OF STATE... long-range acquisition estimates....

  13. 48 CFR 605.404 - Release of long-range acquisition estimates.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 4 2011-10-01 2011-10-01 false Release of long-range acquisition estimates. 605.404 Section 605.404 Federal Acquisition Regulations System DEPARTMENT OF STATE... long-range acquisition estimates....

  14. 48 CFR 1305.404 - Release of long-range acquisition estimates.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 5 2014-10-01 2014-10-01 false Release of long-range acquisition estimates. 1305.404 Section 1305.404 Federal Acquisition Regulations System DEPARTMENT OF COMMERCE... long-range acquisition estimates....

  15. 48 CFR 5.404 - Release of long-range acquisition estimates.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 1 2013-10-01 2013-10-01 false Release of long-range...-range acquisition estimates. To assist industry planning and to locate additional sources of supply, it may be desirable to publicize estimates of unclassified long-range acquisition requirements....

  16. 48 CFR 1305.404 - Release of long-range acquisition estimates.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 5 2012-10-01 2012-10-01 false Release of long-range acquisition estimates. 1305.404 Section 1305.404 Federal Acquisition Regulations System DEPARTMENT OF COMMERCE... long-range acquisition estimates....

  17. 48 CFR 5.404-2 - Announcements of long-range acquisition estimates.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...-range acquisition estimates. 5.404-2 Section 5.404-2 Federal Acquisition Regulations System FEDERAL... Announcements of long-range acquisition estimates. Further publicizing, consistent with the needs of the individual case, may be accomplished by announcing through the GPE that long-range acquisition estimates...

  18. 48 CFR 405.404 - Release of long-range acquisition estimates.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 4 2012-10-01 2012-10-01 false Release of long-range acquisition estimates. 405.404 Section 405.404 Federal Acquisition Regulations System DEPARTMENT OF... Release of long-range acquisition estimates....

  19. 48 CFR 5.404 - Release of long-range acquisition estimates.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 1 2012-10-01 2012-10-01 false Release of long-range...-range acquisition estimates. To assist industry planning and to locate additional sources of supply, it may be desirable to publicize estimates of unclassified long-range acquisition requirements....

  20. 48 CFR 5.404-2 - Announcements of long-range acquisition estimates.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...-range acquisition estimates. 5.404-2 Section 5.404-2 Federal Acquisition Regulations System FEDERAL... Announcements of long-range acquisition estimates. Further publicizing, consistent with the needs of the individual case, may be accomplished by announcing through the GPE that long-range acquisition estimates...

  1. 23 CFR 450.214 - Development and content of the long-range statewide transportation plan.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... long-range statewide transportation plan should include capital, operations and management strategies... transportation system. The long-range statewide transportation plan may consider projects and strategies that... shall reference, summarize, or contain any applicable short-range planning studies; strategic planning...

  2. 23 CFR 450.214 - Development and content of the long-range statewide transportation plan.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... long-range statewide transportation plan should include capital, operations and management strategies... transportation system. The long-range statewide transportation plan may consider projects and strategies that... shall reference, summarize, or contain any applicable short-range planning studies; strategic planning...

  3. 23 CFR 450.214 - Development and content of the long-range statewide transportation plan.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...., transportation, safety, economic development, social and environmental effects, or energy) that were relevant to... 23 Highways 1 2011-04-01 2011-04-01 false Development and content of the long-range statewide... Programming § 450.214 Development and content of the long-range statewide transportation plan. (a) The State...

  4. 23 CFR 450.214 - Development and content of the long-range statewide transportation plan.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...., transportation, safety, economic development, social and environmental effects, or energy) that were relevant to... 23 Highways 1 2014-04-01 2014-04-01 false Development and content of the long-range statewide... Programming § 450.214 Development and content of the long-range statewide transportation plan. (a) The State...

  5. 23 CFR 450.214 - Development and content of the long-range statewide transportation plan.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...., transportation, safety, economic development, social and environmental effects, or energy) that were relevant to... 23 Highways 1 2013-04-01 2013-04-01 false Development and content of the long-range statewide... Programming § 450.214 Development and content of the long-range statewide transportation plan. (a) The State...

  6. Long Range Plan for Information Systems from the State Board of Education.

    ERIC Educational Resources Information Center

    Texas Education Agency, Austin.

    The Information Systems Long Range Plan specifically addresses Goal four of the Texas State Board of Education's (SBOE's) "Long-Range Plan for Public School Education" dealing with efficient management and organization of the educational system. To facilitate this goal, the SBOE in 1986 approved and directed the Texas Education Agency to…

  7. 14 CFR 125.267 - Flight navigator and long-range navigation equipment.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Flight navigator and long-range navigation... Requirements § 125.267 Flight navigator and long-range navigation equipment. (a) No certificate holder may...-range means of navigation which enable a reliable determination to be made of the position of the...

  8. 14 CFR 125.267 - Flight navigator and long-range navigation equipment.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Flight navigator and long-range navigation... Requirements § 125.267 Flight navigator and long-range navigation equipment. (a) No certificate holder may...-range means of navigation which enable a reliable determination to be made of the position of the...

  9. 14 CFR 125.267 - Flight navigator and long-range navigation equipment.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Flight navigator and long-range navigation... Requirements § 125.267 Flight navigator and long-range navigation equipment. (a) No certificate holder may...-range means of navigation which enable a reliable determination to be made of the position of the...

  10. 14 CFR 125.267 - Flight navigator and long-range navigation equipment.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Flight navigator and long-range navigation... Requirements § 125.267 Flight navigator and long-range navigation equipment. (a) No certificate holder may...-range means of navigation which enable a reliable determination to be made of the position of the...

  11. Monte Carlo Study of One-Dimensional Ising Models with Long-Range Interactions

    NASA Astrophysics Data System (ADS)

    Tomita, Yusuke

    2009-01-01

    Recently, Fukui and Todo have proposed a new effective Monte Carlo algorithm for long-range interacting systems. Using the algorithm with the nonequilibrium relaxation method, we investigated long-range interacting one-dimensional Ising models both ferromagnetic and antiferromagnetic with the nearest-neighbor ferromagnetic interaction. For the antiferromagnetic model, we found the systems are paramagnetic at finite temperatures.

  12. The non-stop road from concrete to abstract: high concreteness causes the activation of long-range networks

    PubMed Central

    Weiss, Sabine; Müller, Horst M.

    2013-01-01

    Current grounding theories propose that sensory-motor brain systems are not only modulated by the comprehension of concrete but also partly of abstract language. In order to investigate whether concrete or abstract language elicits similar or distinct brain activity, neuronal synchronization patterns were investigated by means of long-range EEG coherence analysis. Participants performed a semantic judgment task with concrete and abstract sentences. EEG coherence between distant electrodes was analyzed in various frequencies before and during sentence processing using a bivariate AR-model with time-varying parameters. The theta frequency band (3–7 Hz) reflected common and different synchronization networks related to working memory processes and memory-related lexico-semantic retrieval during processing of both sentence types. In contrast, the beta1 band (13–18 Hz) showed prominent differences between both sentence types, whereby concrete sentences were associated with higher coherence implicating a more widespread range and intensity of mental simulation processes. The gamma band (35–40 Hz) reflected the sentences' congruency and indicated the more difficult integration of incongruent final nouns into the sentence context. Most importantly, findings support the notion that different cognitive operations during sentence processing are associated with multiple brain oscillations. PMID:24027515

  13. DNA and IκBα both induce long range conformational changes in NFκB.

    PubMed

    Ramsey, Kristen M; Dembinski, Holly E; Chen, Wei; Ricci, Clarisse G; Komives, Elizabeth A

    2017-02-26

    We recently discovered that IκBα enhances the rate of release of NFκB from DNA target sites in a process we have termed molecular stripping. Coarse-grained molecular dynamics simulations of the stripping pathway revealed two mechanisms for the enhanced release rate; the negatively charged PEST region of IκBα electrostatically repels the DNA, and binding of IκBα appears to twist the NFκB heterodimer so that DNA can no longer bind. Here we report amide hydrogen/deuterium exchange data that reveals long-range allosteric changes in the NFκB (RelA-p50) heterodimer induced by DNA or IκBα binding. The data suggest that the two immunoglobulin-like subdomains of each Rel-homology region, which are connected by a flexible linker in the heterodimer, communicate in such a way that when DNA binds to the N-terminal DNA binding domains, the nuclear localization signal becomes more highly exchanging. Conversely, when IκBα binds to the dimerization domains, amide exchange throughout the DNA binding domains is decreased as if the entire domain is becoming globally stabilized. The results help understand how the subtle mechanism of molecular stripping actually occurs.

  14. Conservation of long-range synteny and microsynteny between the genomes of two distantly related nematodes

    PubMed Central

    Guiliano, DB; Hall, N; Jones, SJM; Clark, LN; Corton, CH; Barrell, BG; Blaxter, ML

    2002-01-01

    Background Comparisons between the genomes of the closely related nematodes Caenorhabditis elegans and Caenorhabditis briggsae reveal high rates of rearrangement, with a bias towards within-chromosome events. To assess whether this pattern is true of nematodes in general, we have used genome sequence to compare two nematode species that last shared a common ancestor approximately 300 million years ago: the model C. elegans and the filarial parasite Brugia malayi. Results An 83 kb region flanking the gene for Bm-mif-1 (macrophage migration inhibitory factor, a B. malayi homolog of a human cytokine) was sequenced. When compared to the complete genome of C. elegans, evidence for conservation of long-range synteny and microsynteny was found. Potential C. elegans orthologs for II of the 12 protein-coding genes predicted in the B. malayi sequence were identified. Ten of these orthologs were located on chromosome I, with eight clustered in a 2.3 Mb region. While several, relatively local, intrachromosomal rearrangements have occurred, the order, composition, and configuration of two gene clusters, each containing three genes, was conserved. Comparison of B. malayi BAC-end genome survey sequence to C. elegans also revealed a bias towards intrachromosome rearrangements. Conclusions We suggest that intrachromosomal rearrangement is a major force driving chromosomal organization in nematodes, but is constrained by the interdigitation of functional elements of neighboring genes. PMID:12372145

  15. Long-range correlations and burstiness in written texts: Universal and language-specific aspects

    NASA Astrophysics Data System (ADS)

    Constantoudis, Vassilios; Kalimeri, Maria; Diakonos, Fotis; Karamanos, Konstantinos; Papadimitriou, Constantinos; Chatzigeorgiou, Manolis; Papageorgiou, Harris

    2016-08-01

    Recently, methods from the statistical physics of complex systems have been applied successfully to identify universal features in the long-range correlations (LRCs) of written texts. However, in real texts, these universal features are being intermingled with language-specific influences. This paper aims at the characterization and further understanding of the interplay between universal and language-specific effects on the LRCs in texts. To this end, we apply the language-sensitive mapping of written texts to word-length series (wls) and analyse large parallel (of same content) corpora from 10 languages classified to four families (Romanic, Germanic, Greek and Uralic). The autocorrelation functions of the wls reveal tiny but persistent LRCs decaying at large scales following a power-law with a language-independent exponent ˜0.60-0.65. The impact of language is displayed in the amplitude of correlations where a relative standard deviation >40% among the analyzed languages is observed. The classification to language families seems to play a significant role since, the Finnish and Germanic languages exhibit more correlations than the Greek and Roman families. To reveal the origins of the LRCs, we focus on the long words and perform burst and correlation analysis in their positions along the corpora. We find that the universal features are linked more to the correlations of the inter-long word distances while the language-specific aspects are related more to their distributions.

  16. Long-range looping of a locus control region drives tissue-specific chromatin packing within a multigene cluster

    PubMed Central

    Tsai, Yu-Cheng; Cooke, Nancy E.; Liebhaber, Stephen A.

    2016-01-01

    Abstract The relationships of higher order chromatin organization to mammalian gene expression remain incompletely defined. The human Growth Hormone (hGH) multigene cluster contains five gene paralogs. These genes are selectively activated in either the pituitary or the placenta by distinct components of a remote locus control region (LCR). Prior studies have revealed that appropriate activation of the placental genes is dependent not only on the actions of the LCR, but also on the multigene composition of the cluster itself. Here, we demonstrate that the hGH LCR ‘loops’ over a distance of 28 kb in primary placental nuclei to make specific contacts with the promoters of the two GH genes in the cluster. This long-range interaction sequesters the GH genes from the three hCS genes which co-assemble into a tightly packed ‘hCS chromatin hub’. Elimination of the long-range looping, via specific deletion of the placental LCR components, triggers a dramatic disruption of the hCS chromatin hub. These data reveal a higher-order structural pathway by which long-range looping from an LCR impacts on local chromatin architecture that is linked to tissue-specific gene regulation within a multigene cluster. PMID:26893355

  17. Magnetic hyperthermia dosimetry by biomechanical properties revealed in magnetomotive optical coherence elastography (MM-OCE) (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Huang, Pin-Chieh; Marjanovic, Marina; Spillman, Darold R.; Odintsov, Boris M.; Boppart, Stephen A.

    2016-03-01

    Magnetic nanoparticles (MNPs) have been utilized in magnetic hyperthermia to treat solid tumors. Under an appropriate AC magnetic field, energy can be transferred to the MNPs to heat up the intended tissue target while sparing non-targeted healthy tissue. However, a sensitive monitoring technique for the dose of MNP thermal therapy is desirable in order to prevent over-treatment and collateral injury. Typical hyperthermia dosimetry often relies on changes in imaging properties or temperature measurements based on the thermal distribution. Alternative dosimetric indicators can include the biomechanical properties of the tissue, reflecting the changes due to protein denaturation, coagulation, and tissue dehydration during hyperthermia treatments. Tissue stiffness can be probed by elastography modalities including MRI, ultrasound imaging, and optical coherence elastography (OCE), with OCE showing the highest displacement sensitivity (tens of nanometers). Magnetomotive optical coherence elastography (MM-OCE) is one type of OCE that utilizes MNPs as internal force transducers to probe the tissue stiffness. Therefore, we examined the feasibility of evaluating the hyperthermia dose based on the elasticity changes revealed by MM-OCE. Superparamagnetic MNPs were applied to ex vivo tissue specimens for both magnetic hyperthermia and MM-OCE experiments, where temperature and elastic modulus were obtained. A correlation between temperature rise and measured stiffness was observed. In addition, we found that with repetitive sequential treatments, tissue stiffness increased, while temperature rise remained relatively constant. These results potentially suggest that MM-OCE could indicate the irreversible changes the tissue undergoes during thermal therapy, which supports the idea for MM-OCE-based hyperthermia dosage control in future applications.

  18. Long range intermolecular interactions between the alkali diatomics Na2, K2, and NaK

    NASA Astrophysics Data System (ADS)

    Zemke, Warren T.; Byrd, Jason N.; Michels, H. Harvey; Montgomery, John A.; Stwalley, William C.

    2010-06-01

    Long range interactions between the ground state alkali diatomics Na2-Na2, K2-K2, Na2-K2, and NaK-NaK are examined. Interaction energies are first determined from ab initio calculations at the coupled-cluster with singles, doubles, and perturbative triples [CCSD(T)] level of theory, including counterpoise corrections. Long range energies calculated from diatomic molecular properties (polarizabilities and dipole and quadrupole moments) are then compared with the ab initio energies. A simple asymptotic model potential ELR=Eelec+Edisp+Eind is shown to accurately represent the intermolecular interactions for these systems at long range.

  19. Long range intermolecular interactions between the alkali diatomics Na(2), K(2), and NaK.

    PubMed

    Zemke, Warren T; Byrd, Jason N; Michels, H Harvey; Montgomery, John A; Stwalley, William C

    2010-06-28

    Long range interactions between the ground state alkali diatomics Na(2)-Na(2), K(2)-K(2), Na(2)-K(2), and NaK-NaK are examined. Interaction energies are first determined from ab initio calculations at the coupled-cluster with singles, doubles, and perturbative triples [CCSD(T)] level of theory, including counterpoise corrections. Long range energies calculated from diatomic molecular properties (polarizabilities and dipole and quadrupole moments) are then compared with the ab initio energies. A simple asymptotic model potential E(LR)=E(elec)+E(disp)+E(ind) is shown to accurately represent the intermolecular interactions for these systems at long range.

  20. Research on risk long range identification for vessel traffic dynamic system

    NASA Astrophysics Data System (ADS)

    Qi, Ji; Guo, Ruijuan; Wang, Xiaoyu; Zhang, Hainan

    2017-09-01

    Vessel Long-range identification and tracking system has already been widely installed and applied in vessel. In this paper AIS system, vessel reporting system and LRIT in China are compared and analyzed based on the coverage area, confidentiality and accuracy of the LRIT information. Vessel Long-range identification and tracking model is established through a combination of AIS with LRIT system, which is applied to the research of vessel traffic dynamic system risk long range identification. Finally, the application of LRIT in the maritime field is discussed.