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Sample records for cummings complex abitibi

  1. Intra-sill magmatic evolution in the Cummings Complex, Abitibi greenstone belt: Tholeiitic to calc-alkaline magmatism recorded in an Archaean subvolcanic conduit system

    NASA Astrophysics Data System (ADS)

    Bédard, Jean H.; Leclerc, François; Harris, Lyal B.; Goulet, Normand

    2009-07-01

    The stratigraphy of the Abitibi greenstone belt in the Chibougamau area (southern Superior Province, Québec), is dominated by 2 cycles of mafic-felsic metavolcanic and metasedimentary rocks constituting the Roy Group, which is riddled by metagabbroic sills (25%). The Doré Lake Complex (DLC, 2728 Ma) is emplaced into the lower Roy Group. The Cummings Complex sills (2717 Ma) were injected between the Bruneau member and Blondeau Formations of the 2nd Roy Group cycle. The sills of the Cummings Complex (Roberge, Ventures and Bourbeau Sills) contain metaperidotite, metapyroxenite, metagabbro and metagranophyric facies. The trace element contents of melts in equilibrium with these metacumulate rocks were calculated and are compared to Roy Group lavas to clarify the regional magmatic history. Many DLC model melts have fractionated trace element profiles, with LILE-LREE-enrichment, HREE-depletion, and negative Nb-Ta-anomalies suggesting that the DLC formed largely from calc-alkaline melts extracted from garnet-bearing residues. The DLC is coeval with, and shows geochemical resemblances to Waconichi Formation tuffs (the felsic cap of the 1st Roy Group cycle), suggesting it could represent the Waconichi's shallow magma chamber. Meta-anorthosite rafts from the para-autochtonous zone of the Grenville province yield model melts closely resembling those of the DLC and are correlated on this basis. Most Roy Group sills yield model melts with trace element patterns typical of Archaean tholeiites, suggesting they fed the regionally-dominant tholeiitic volcanic plain lavas of the Roy Group. Models for the Cummings Complex imply that it contained two types of magma. Model melts from the Roberge Sill have strongly fractionated calc-alkaline-like trace element patterns, while those of the Ventures and Bourbeau Sills are mostly flat, N-MORB-normalized tholeiitic-like patterns that cannot be derived from the Roberge Sill melts by fractional crystallization. The Roberge Sill must have a

  2. Tripodal bis(imidazole) thioether copper(I) complexes: mimics of the Cu(M) site of copper hydroxylase enzymes.

    PubMed

    Zhou, Lei; Powell, Douglas; Nicholas, Kenneth M

    2007-09-17

    Tripodal bis(imidazole) thioether ligands, (N-methyl-4,5-diphenyl-2-imidazolyl)2C(OR)C(CH3)2SR' (BIT(OR,SR'); R = H, CH3; R' = CH3, C(CH3)3, C(C6H5)3), have been prepared, offering the same N2S donor atom set as the CuM binding site of the hydroxylase enzymes, dopamine beta hydroxylase and peptidylglycine hydroxylating monooxygenase. Isolable copper(I) complexes of the type [(BIT(OR,SMe))Cu(CO)]PF6 (3a and 3b) are produced in reactions of the respective tripodal ligands 1a (R = H) and 1b (R = Me) with [Cu(CH3CN)4]PF6 in CH2Cl2 under CO (1 atm); the pyramidal structure of 3a has been determined crystallographically. The infrared (IR) nu(CO)'s of 3a and 3b (L = CO) are comparable to those of the Cu(M)-carbonylated enzymes, indicating similar electronic character at the copper centers. The reaction of [(BIT(OH,SMe))Cu(CH3CN)]PF6 (2a) with dioxygen produces [(BIT(O,SOMe))2Cu2(DMF)2](PF6)2 (4), whose X-ray structure revealed the presence of bridging BIT-alkoxo ligands and terminal -SOMe groups. In contrast, oxygenation of 2b (R = Me) affords crystallographically defined [(BIT(OMe,SMe))2Cu2(mu-OH)2](OTf)2 (5), in which the copper centers are oxygenated without accompanying sulfur oxidation. Complex 5 in DMF is transformed into five-coordinate, mononuclear [CuII(BIT(OMe,SMe))(DMF)2](PF6)2 (6). The sterically hindered BIT(OR,SR') ligands 9 and 10 (R' = t-Bu; R = H, Me) and 11 and 12 (R' = CPh3; R = H, Me) were also prepared and examined for copper coordination/oxygenation. Oxygenation of copper(I) complex 13b derived from the BIT(OMe,SBu-t) ligand is slow, relative to 2b, producing a mixture of (BIT(OMe,SBu-t))2Cu2(mu-OH)2-type complexes 14b and 15b in which the -SBu-t group is uncoordinated; one of these complexes (15b) has been ortho-oxygenated on a neighboring aryl group according to the X-ray analysis and characterization of the free ligand. Oxygenation of the copper(I) complex derived from BIT(OMe,SCPh3) ligand 12 produces a novel dinuclear disulfide complex, [(BIT

  3. Fifty years of Jaynes-Cummings physics

    NASA Astrophysics Data System (ADS)

    Greentree, Andrew D.; Koch, Jens; Larson, Jonas

    2013-11-01

    This special issue commemorates the 50th anniversary of the seminal paper published by E T Jaynes and F W Cummings [1], the fundamental model which they introduced and now carries their names, and celebrates the remarkable host of exciting research on Jaynes-Cummings physics throughout the last five decades. The Jaynes-Cummings model has been taking the prominent stance as the 'hydrogen atom of quantum optics' [2]. Generally speaking, it provides a fundamental quantum description of the simplest form of coherent radiation-matter interaction. The Jaynes-Cummings model describes the interaction between a single electromagnetic mode confined to a cavity, and a two-level atom. Energy is exchanged between the field and the atom, which leads directly to coherent population oscillations (Rabi oscillations) and superposition states (dressed states). Being exactly solvable, the Jaynes-Cummings model serves as a most useful toy model, and as such it is a textbook example of the physicists' popular strategy of simplifying a complex problem to its most elementary constituents. Thanks to the simplicity of the Jaynes-Cummings model, this caricature of coherent light-matter interactions has never lost its appeal. The Jaynes-Cummings model is essential when discussing experiments in quantum electrodynamics (indeed the experimental motivation of the Jaynes-Cummings model was evident already in the original paper, dealing as it does with the development of the maser), and it has formed the starting point for much fruitful research ranging from ultra-cold atoms to cavity quantum electrodynamics. In fact, Jaynes-Cummings physics is at the very heart of the beautiful experiments by S Haroche and D Wineland, which recently earned them the 2012 Nobel Prize in physics. Indeed, as with most significant models in physics, the model is invoked in settings that go far beyond its initial framework. For example, recent investigations involving multi-level atoms, multiple atoms [3, 4], multiple

  4. Fifty years of Jaynes-Cummings physics

    NASA Astrophysics Data System (ADS)

    Greentree, Andrew D.; Koch, Jens; Larson, Jonas

    2013-11-01

    This special issue commemorates the 50th anniversary of the seminal paper published by E T Jaynes and F W Cummings [1], the fundamental model which they introduced and now carries their names, and celebrates the remarkable host of exciting research on Jaynes-Cummings physics throughout the last five decades. The Jaynes-Cummings model has been taking the prominent stance as the 'hydrogen atom of quantum optics' [2]. Generally speaking, it provides a fundamental quantum description of the simplest form of coherent radiation-matter interaction. The Jaynes-Cummings model describes the interaction between a single electromagnetic mode confined to a cavity, and a two-level atom. Energy is exchanged between the field and the atom, which leads directly to coherent population oscillations (Rabi oscillations) and superposition states (dressed states). Being exactly solvable, the Jaynes-Cummings model serves as a most useful toy model, and as such it is a textbook example of the physicists' popular strategy of simplifying a complex problem to its most elementary constituents. Thanks to the simplicity of the Jaynes-Cummings model, this caricature of coherent light-matter interactions has never lost its appeal. The Jaynes-Cummings model is essential when discussing experiments in quantum electrodynamics (indeed the experimental motivation of the Jaynes-Cummings model was evident already in the original paper, dealing as it does with the development of the maser), and it has formed the starting point for much fruitful research ranging from ultra-cold atoms to cavity quantum electrodynamics. In fact, Jaynes-Cummings physics is at the very heart of the beautiful experiments by S Haroche and D Wineland, which recently earned them the 2012 Nobel Prize in physics. Indeed, as with most significant models in physics, the model is invoked in settings that go far beyond its initial framework. For example, recent investigations involving multi-level atoms, multiple atoms [3, 4], multiple

  5. WRR editor Ronald Cummings

    NASA Astrophysics Data System (ADS)

    1984-04-01

    It has been nearly a year since Ronald Cummings took over as policy sciences editor of Water Resources Research (WRR), and in that time he has worked to make the journal live up to its role as “an interdisciplinary journal integrating research in the social and natural sciences of water.” Cummings takes the “interdisciplinary” part seriously. “I'd like to see a much broader range of policy issues presented to readers,” he says. “I would hope it would then stimulate interchange between our colleagues concerning evolving issues of the '80s and '90s.”Cummings brings a solid background as a resource economist to his 4-year term as editor, which began last January and runs until December 1987. Cummings succeeds Jared Cohon as policy sciences editor. Stephen J. Burges is the WRR editor for hydrological, physical, chemical, and biological sciences. Now a Professor of Economics and Director of the Program in Natural Resources Economics at the University of New Mexico, Cummings is a past president of the Association of Environmental and Resource Economists. He has been a consultant in matters of water resources management, forestry management, and energy policy for more than a decade, working on projects in both the United States and Latin America. Since joining the faculty at New Mexico in 1975, he has, among other things, worked with engineers at the Los Alamos National Laboratory in developing operation'management models for hot, dry rock geothermal systems.

  6. Lode Gold Deposits and Archean Mantle Plume-Island Arc Interaction, Abitibi Subprovince, Canada.

    PubMed

    Wyman; Kerrich; Groves

    1999-11-01

    In combination with seismic interpretations and geochronological constraints, the association of juvenile arc-type low-Ti tholeiitic basalts with komatiites in the southeastern Abitibi subprovince, Canada, supports a history of subduction step back following Late Archean mantle plume-island arc interaction. The resulting paired collision zones preserved abundant komatiites and numerous massive sulphide deposits and established the critical metallogenic features to concentrate the majority of Canada's Precambrian gold resources in a small area of the southern Abitibi subprovince. PMID:10517886

  7. Archaean wrench-fault tectonics in the Abitibi greenstone belt of Canada

    NASA Technical Reports Server (NTRS)

    Hubert, C.

    1986-01-01

    A tectonic model is proposed in which the southern Abitibi belt formed in a series of rift basins which dissected an earlier formed volcanic arc. Comparisons can be made with Phanerozoic areas such as, the Hokuroko basin of Japan, the Taupo volcanic zone of new Zealand and the Sumatra and Nicaragua volcanic arcs. In addition the identification of the major E - W thrust shears make it possible to speculate that the southern Abitibi belt comprises a collage of blocks of terrane which have been accreted against a more stable continental margin or microcontinent. If this interpretation is correct analogies can be made with the SW margin of the U.S.A. in which recently formed blocks of volcanic terrane are being accreted against its western margin.

  8. Some Speculations Concerning The Abitibi Greenstone Belt As A Possible Analog To The Early Martian Crust

    NASA Astrophysics Data System (ADS)

    Russell, M.; Allwood, A.; Anderson, R. B.; Atkinson, B.; Beaty, D.; Bristow, T. F.; Ehlmann, B. L.; Grotzinger, J. P.; Hand, K. P.; Halevy, I.; Hurowitz, J. A.; Knoll, A.; McCleese, D. J.; Milliken, R.; Stolper, D. A.; Stolper, E. M.; Tosca, N. J.; Agouron Mars Simulation Field Team

    2011-12-01

    The Noachian crust of Mars comprises basaltic and, potentially, komatiitic lavas derived from a hot mantle slightly more reducing and sulfur-rich than that of the Earth. Ultramafic volcanic sequences of the ~2.7Ga Tisdale Group of the Abitibi Greenstone Belt, Ontario, provide a potential analog to these early martian lavas. The Abitibi rocks are a possible source of quartz veins carrying, in places, pyrite, carbonate and gold. These were hydrothermally introduced into volcanic and sedimentary rocks during greenschist metamorphism. Kilometer-scale talc-magnesite zones, resulting from the carbonation of serpentinized ultramafics, may have been the source and seawater, with some magmatic addition, was probably responsible for the pervasive alteration, although the chemical nature of hydrothermal fluids circulating in such piles depends upon the temperature of wall-rock interactions and is largely independent of fluid origin. Any sulfides and gold in unaltered ultramafic putative source rocks may have been lost to the invasive convective fluids. Given high heat flow and the presence of a hydrosphere, hydrothermal convection cells were probably the main mechanism of heat transfer through the crust on both planets. Exploration of the Abitibi belt provides a template for possible martian exploration strategies. Orbital remote sensing indicates that some ultramafic rocks on Mars have also been serpentinized and isolated areas of magnesite have been recently discovered, overlying altered mafic crust, with characteristic ridges at scales of a few hundred meters. While cogent arguments have been made favoring sedimentary exhalative accumulations of hydrothermal silica of the kind that are known to harbor bacteria on our own planet, no in situ siliceous sinters or even quartz veins have been identified with certainty on Mars. Here, we report on the mineralogic and visible to infrared spectral characteristics of mafic and ultramafic lithologies at Abitibi for comparison to

  9. Single zircon age constraints on the tectonic juxtaposition of the Archean Abitibi greenstone belt and Pontiac subprovince, Quebec, Canada

    SciTech Connect

    Feng, R.; Kerrich, R. )

    1991-11-01

    Zircons from metasediments and granitoids in the high-grade Lacorne block within the low-grade Archean Abitibi greenstone belt have been dated by single zircon Pb-evaporation technique, yielding {sup 207}Pb/{sup 206}Pb minimum ages. Detrital zircons in the mature clastic metasediments of the Lacorne block display a range of ages from 2,691 {plus minus} 8 Ma to 3,042 {plus minus} 6 Ma. The younger zircon ages thus impose an upper limit for deposition and indicate that the high-grade Lacorne block is not basement to the Abitibi supracrustal sequence (2,747-2,680 Ma). Existence of abundant (69%) older detrital zircons (> 2,750 Ma) suggest in turn that the Abitibi supracrustal rocks are not the source of the Lacorne sediments. Two generations of granitoids occur in the Lacorne block, an early monosodiorite-monzonite-granodiorite-syenite series and a younger S-type garnet-muscovite granite series. This contrasts with granitoid magmatism in the Abitibi greenstone belt which ended at {approximately}2675 Ma. The Pontiac subprovince to the south of the Abitibi greenstone belt shares all of the above features of the Lacorne block, including detrital zircon ages as well as the composition and timing of granitoid magmatism. This is interpreted detrital zircon ages as well as the composition and timing of granitoid magmatism. This is interpreted to indicate that the Lacorne block was originally part of the same tectonic terrane as the Pontiac subprovince. After development of the MMGS magmatism (21,670-2,680 Ma), the Pontiac subprovince locally underthrust the Abitibi greenstone belt, and crustal thickening promoted partial melting of underthrust Pontiac metasediments to form the {approximately}2,644 {plus minus} 13 Ma S-type granites.

  10. Volcanic environments of ore formation in the late Archaean Abitibi greenstone belt of Canada

    SciTech Connect

    Ludden, J.N.

    1985-01-01

    The tectonic and petrological evolution of the late Archaean Abitibi greenstone belt indicate both emergent and submergent volcanism played a role in its metallogenesis. At approximately 2700 m.y. the southern volcanic zone (SVZ) of the Abitibi belt was dominated by a rift-related tectonic and volcanic evolution in a transcurrent (wrench) fault regime. The tholeiitic and komatiitic magmas and associated differentiated volcanic rocks had access to shallow crustal levels allowing the development of submarine hydrothermal systems and syngenetic Cu-Zn (Noranda type) massive sulfide ore bodies. These deposits formed along a 300 km. axis in submerging, fault bounded, basins. In contrast, the northern volcanic zone (the Chibougamau-Chapais area) formed at 2720 m.y and was characterized by emergent volcanoes emplaced on a continental crust and cored by coeval diorite-tonalite plutons. Mafic magma was inhibited from the crust by fractionated and contaminated magmas. This resulted in the emplacement of hydrous calc-alkaline magmas and associated porphyry-type epigenetic Cu(Au) massive sulfides. Au-lode deposits are predominantly located near major shear-zones in the SVZ. The are forming solutions were released as a result of burial due to wrench faulting. The dynamic regime of the rifted SVZ may have resulted in the syngenetic massive sulfides, the Au-lode deposits, metamorphism and sedimentation being synchronous on a regional scale, whilst on a local scale, Au-lodes superimpose and replace massive sulfides, iron formation and metamorphic isograds.

  11. Spectroscopic investigation of the three prototropic forms of a β-cyclodextrin-indolizine derivative from its inclusion-cum-charge-transfer complexes

    NASA Astrophysics Data System (ADS)

    Ghosh, Bankim Chandra; Deb, Nipamanjari; Becuwe, Matthieu; Fourmentin, Sophie; Mukherjee, Asok K.

    2011-02-01

    By absorption and fluorescence (steady state and time-resolved) studies, three prototropic forms of (N-6-deoxy-β-cyclodextrin-6-yl-1-aminocarbonyl)-3-(4-fluorobenzoyl)-7-pyridine-4-yl indolizine, (1) have been established and shown to be a potential fluorescent pH sensor with switching action. Inclusion complexes of (1) with a number of quinones have been shown to exhibit charge transfer (CT) spectra in aqueous medium and variation of such spectra with change in pH yield the proton affinity of the biologically important indolizine moiety. Förster cycle reveals that in the excited state indolizine moiety has a greater proton affinity. The nature of the CT transitions (whether n-donor-π-acceptor or π-donor-π-acceptor) has been experimentally ascertained.

  12. Composition of komatiite melts from Abitibi and Belingwe inferred from melt inclusions in olivine phenocrysts.

    NASA Astrophysics Data System (ADS)

    Asafov, Evgeny; Sobolev, Alexander; Arndt, Nicholas; Batanova, Valentina

    2015-04-01

    Komatiites are the products of extreme amounts of partial melting and hence are best indicators of the composition of their mantle sources. However, the most known komatiites are highly altered, and this prevents the use of their compositions to estimate the volatile and mobile element contents of the mantle. To estimate the concentrations of these elements, we analyzed melt inclusions in high-Mg olivine phenocrysts from two 2.7 Ga sample suites, one from Abitibi greenstone belt, Canada and the other from the Belingwe greenstone belt, Zimbabwe. Fresh olivine grains 0.2-0.5 mm across were heated for 5 minutes and quenched at 1350°C in a C-O-H atmosphere with oxygen fugacity corresponding to quartz-fayalite-magnetite buffer. Homogenized melt inclusions were exposed at the surface of grains and analyzed by electron probe micro-analyzer for concentrations of Mg, Si, Ti, Al, Fe, Mn, Ca, Na, Cr, P, K, Cl and S. The size of melt inclusions ranges from 20 to 80 µm. The measured compositions were adjusted to equilibrium with host olivine with iron loss correction using Petrolog3 software (Danyushevsky & Plechov, G-cubed 12, 2011). Cracked inclusions were filtered out using their low S contents. Data on the volatile components Cl and S were thus obtained for the first time for the melt inclusions in Abitibi komatiites. Calculated melt compositions range from 19.5 to 27.1 wt.% MgO in Abitibi samples and from 18.9 to 22 wt.% in Belingwe samples. Other elements, except Cl and K, show strong negative correlation with MgO and follow an olivine fractionation trend. Concentrations of Si, Ti, Al, and Ca are consistent with the corresponding compositions of whole rocks. Variations of Cl and K cannot be explained by fractionation of olivine and are attributed to the variations in parental melt. The melt inclusion compositions from Abitibi and Belingwe komatiites have similar Ca, Na, K and S concentrations at the same concentration of Mg but Al and Ti are lower in Belingwe samples

  13. The Key Tuffite, Matagami Camp, Abitibi Greenstone Belt, Canada: petrogenesis and implications for VMS formation and exploration

    NASA Astrophysics Data System (ADS)

    Genna, Dominique; Gaboury, Damien; Roy, Gilles

    2014-04-01

    The Key Tuffite is a stratigraphic marker unit for most of the zinc-rich volcanogenic massive sulfide deposits of the Matagami Camp in the Abitibi Greenstone Belt. This 2- to 6-m-thick unit was previously interpreted as a mixture of ash fall (andesitic to rhyolitic tuffaceous components) and volcanogenic massive sulfide (VMS)-related chemical seafloor precipitate (exhalative component). Previous attempts to develop geochemical exploration vectoring tools using metal content within the Key Tuffite were mostly inconclusive due to the complex nature of the Key Tuffite unit and a poor understanding of its composition, origin and relationship with the VMS-forming hydrothermal systems. Detailed mapping and thorough lithogeochemistry of the Key Tuffite in the vicinity of the Perseverance and Bracemac-McLeod deposits indicate that the Key Tuffite is a homogeneous calc-alkaline, andesitic tuff that was deposited before the VMS deposits were formed. The unit is mostly devoid of exhalative component, but it is strongly hydrothermally altered close to orebodies. This is characterized by a strong proximal chloritization and a distal sericitization, which grades laterally into the unaltered Key Tuffite. Neither the Key Tuffite nor the ore was formed by seafloor exhalative processes for the two studied deposits. This probably explains why previously proposed exploration models based on metal scavenging proved unsuccessful and suggests that a re-evaluation of the exhalative model should be done at the scale of the mining camp. However, as shown in this study, hydrothermal alteration can be used to vector towards ore along the Key Tuffite.

  14. Archean terrane docking: upper crust collision tectonics, Abitibi greenstone belt, Quebec, Canada

    NASA Astrophysics Data System (ADS)

    Mueller, W. U.; Daigneault, R.; Mortensen, J. K.; Chown, E. H.

    1996-11-01

    The northern (NVZ) and southern volcanic zones (SVZ) of the Abitibi greenstone belt are separated by the major E-trending Destor-Porcupine-Manneville fault zone (DPMFZ). The DPMFZ is interpreted to be the locus of Archean terrane docking between the older diffuse volcanic arc of the NVZ (2730-2710 Ma) and the younger arc segments of the SVZ (2705-2698 Ma). Two distinct evolutionary phases can be documented along the DPMFZ of the Abitibi greenstone belt and include (1) arc-arc collision occurring between 2697 and 2690 Ma, and (2) arc fragmentation between 2689 and 2680 Ma. Identification of these two events along the DPMFZ is based on detailed structural studies, sedimentary basin analysis, and precise UPb age determinations. The thrusting event, representative of the arc-arc collision phase, is characterized by shallow north-dipping foliations (20-40°) and dip-parallel stretching lineations in the eastern Manneville segment of the DPMFZ. Local overturned mafic pillowed units suggest recumbent folding. Late strike-slip or transcurrent movement displayed in the late-orogenic sedimentary Duparquet Basin records the arc fragmentation phase. Basin geometry, E-trending en-echelon folds, shallow E-plunging stretching lineations and a late NE-striking cleavage cross-cutting the folds support a dextral shear sense along the western Destor-Porcupine segment of the DPMFZ. The sedimentary facies observed in the basin are consistent with those of modern strike-slip basins located along the East Anatolian fault, Turkey (Hazar Lake) and the Hope fault, New Zealand (Hanmer Basin). Precise UPb zircon age determinations from porphyry stocks located at the northern and southern limits of the Duparquet Basin, yielded 2681 ± 1 Ma and 2689 +3.2-2.9 Ma, respectively. These ages constrain the rapid change from thrusting to transcurrent movement. It is apparent that once thrusting ceased the response to oblique subduction continued in the form of strike-slip displacement. Modern

  15. Are the alteration halos of massive sulfide deposits syngenetic Evidence from U-Pb dating of hydrothermal rutile at the Kidd volcanic center, Abitibi subprovince, Canada

    SciTech Connect

    Schandl, E.S.; Davis, D.W.; Krogh, T.E. )

    1990-06-01

    The Kidd volcanic complex is composed of felsic volcanic and subvolcanic rocks of Archean age. Metasomatic events affecting the lithology of the Kidd volcanic complex include silicification, extensive CO{sub 2} metasomatism (carbonate), K-metasomatism (sericite-fuchsite), and chlorite and minor carbonate alterations. Petrographic evidence, supported by stable isotope and fluid inclusion studies, suggests that silicification and early carbonate alteration were synvolcanic, and therefore related to ore deposition. During subsequent extensive K-metasomatism, sericite precipitated in the rhyolite, and fuschsite precipitated in the ultramafic rocks. Although chlorite postdates K-metasomatism, the micas and chlorite are both found in anastomosing microfissures, commonly occupying the same set of fractures. Hydrothermal rutile formed by the breakdown of magnetite-ilmenite during K-metasomatism and chlorite alteration gives an age of 2624 {plus minus} 62 Ma (95% confidence level). It is therefore approximately 100 m.y. younger than syngenetic massive sulfide mineralization (2712 {plus minus} 2 Ma). Sulfide stringers within sericite and chlorite veins suggest some remobilization of the ores during these later events. This alteration assemblage, is identical to that found associated with many lode-gold deposits in the Superior province. Recent dating of micas and rutile associated with gold deposits in the Abitibi subprovince gives comparable ages to the rutile in the Kidd volcanic complex, which must therefore record a widespread, late hydrothermal event affecting mineralized rocks.

  16. Supersymmetry in the Jaynes-Cummings model

    SciTech Connect

    Castanos, Octavio

    2013-06-12

    A review is presented of the Darboux method and its relation to the supersymmetric quantum mechanics, together with the embedding of a n-dimensional scalar Hamiltonian into a supersymmetric matrix. It is also shown that the Jaynes-Cummings model, with or without rotating wave approximation, admit a supersymmetric quantum mechanics description.

  17. Palaeoseismic events recorded in Archaean gold-quartz vein networks, Val d'Or, Abitibi, Quebec, Canada

    NASA Astrophysics Data System (ADS)

    Boullier, Anne-Marie; Robert, François

    1992-02-01

    Archaean gold-quartz vein deposits are commonly hosted in high-angle reverse shear zones and are interpreted to have formed in a regime of horizontal compression and high fluid pressure environment. This paper presents the results of a combined structural and fluid inclusion study on three gold-quartz vein deposits of the Val d'Or area (Abitibi, Quebec) consisting of subhorizontal extensional veins and E-W steeply dipping shear veins. Crack-seal structures, tourmaline fibres, stretched quartz crystals and open-space filling textures indicate that the subhorizontal veins formed by hydraulic fracturing under supralithostatic fluid pressure. CO 2-rich and H 2O + NaCl fluid inclusions, interpreted as two coexisting immiscible fluids, occur typically in microcracks of different orientations interpreted to have formed in the σ1- σ2 plane. Horizontal CO 2-rich fluid inclusion planes are contemporaneous with the opening of these veins (σ 3 vertical). Vertical H 2O + NaCl fluid inclusion planes, as well as some microstructures, such as deformed minerals, indicate that the same extensional veins have experienced episodic vertical shortening (σ 3 horizontal) alternating with the opening events. Deformation and slip/opening also occurred in shear veins in which preferred orientation of fluid inclusion planes is not clear, except that the H 2O + NaCl fluid inclusion planes tend to be oriented at high angles to the slip direction. The successive opening and collapse events in subhorizontal extensional veins are correlated with deformation and slip/opening events in shear veins, respectively, and are attributed to cyclic fluid pressure fluctuations in the system. They are thus consistent with the fault-valve model: sudden drop in fluid pressure from supralithostatic to lower values induces fluid unmixing and occurs immediately post-failure following seismic rupturing along the shear zone. Sealing of the shear veins allows the fluid pressure to build up again and the

  18. Using the Abitibi Greenstone Belt to understand Martian hydrothermal systems and the potential for biosignature preservation in high temperature aqueous environments

    NASA Astrophysics Data System (ADS)

    Hurowitz, J. A.; Abelson, J.; Allwood, A.; Anderson, R. B.; Atkinson, B.; Beaty, D.; Bristow, T. F.; Ehlmann, B. L.; Eigenbrode, J. L.; Grotzinger, J. P.; Hand, K. P.; Halevy, I.; Knoll, A.; McCleese, D. J.; Milliken, R.; Russell, M.; Stolper, D. A.; Stolper, E. M.; Tosca, N. J.

    2011-12-01

    Impact and magmatic driven hydrothermal systems have long been postulated to exist on Mars. Recent observations of high-temperature mineral associations, e.g., smectite-chlorite-carbonate-serpentine, provide evidence consistent with the presence of hydrothermal environments in the ancient Martian rock record. In light of these discoveries, it is instructive to examine fossil hydrothermal systems on Earth to better understand the conditions under which putative Martian hydrothermal mineral assemblages may have formed. Such investigations may prove to be important in the era of Mars Sample Return, as we possess little scientific understanding of the biosignature preservation potential of ancient terrestrial hydrothermal systems. Motivated by these issues, the Agouron Institute organized a Geobiology Field School in July, 2011 to study the 2.7 Ga Abitibi greenstone belt in Ontario, CA. The Abitibi hosts world-renowned economic volcanogenic massive sulfide mineral deposits, and is characterized by a rich suite of lithologies emplaced predominantly in sub-oceanic settings, including komatiites, basalts, and rhyolitic volcanic rocks and banded iron formation, most of which have been hydrothermally altered, remineralized, and tectonically deformed under greenschist facies conditions. During a 10-day excursion to the Abitibi, guided by the Ontario Geological Survey, our team examined these assemblages, performed in-situ analyses using field portable active mid-IR and reflectance VIS-NIR spectrometers, an X-ray diffractometer, and an X-ray fluorescence spectrometer to inform an extensive sampling campaign. These samples have been returned to our laboratories for in-depth analysis. We will report on the outcome of our field campaign and discuss the unique opportunity provided by examination of the Abitibi to compare and contrast the effects of hydrothermal alteration and mineralization on an ocean planet with an active biosphere to a planet where the presence of large, long

  19. 3-D visualization of structural field data: examples from the Archean Caopatina Formation, Abitibi greenstone belt, Québec, Canada

    NASA Astrophysics Data System (ADS)

    de Kemp, Eric A.

    2000-06-01

    A series of 3-D visualization approaches is presented with the aim of developing better interpretation tools for field-based geologists. Structural data from outcrop, mine and regional scales are used to create speculative 3-D surfaces that can be useful in addressing geological problems. These tools could help in resolving cryptic early fold geometries, extending stratiform mineralizations and the sub-surface interpretation of regional thrusts, unconformities or key lithostratigraphic boundaries. Using sparse data sets from the low-relief and structurally complex Archean Abitibi greenstone belt, I have demonstrated that speculative models can be created from such challenging terrains, provided that existing data are respected and that appropriate methods are applied at a given scale. Examples focus on optimizing the 3-D editing environment for making better interpretations. Applied techniques include custom projections of surface traces, 3-D digitizing, simple Bézier surface patches, and non-cylindrical fold construction using field based plunge models. These are implemented as several UNIX AWK programs in conjunction with commercial 3-D visualization and modeling software gOcad © and EarthVision ©. This integration and visualization study shows that complex fold geometries can be more rigorously constructed using constraining structural field data, but that current 3-D technologies are still very cumbersome for hard rock applications. Future development of field based case studies that will help validate and communicate the benefit of these methods is much needed, and will hopefully better articulate specific requirements to software developers. Professional 3-D software developers are encouraged to work towards the implementation of these types of programs in order to move the regional mapping community beyond 2-D and 21/2-D GIS-based modeling. National surveys and explorationists who are responsible for the collection, management, and archiving of geoscience

  20. [Pediamécum: one year of experience].

    PubMed

    Piñeiro Pérez, R; Martínez Fernández-Llamazares, C; Calvo Rey, C; Piñeiro Pérez, A P; Criado Vega, E A; Bravo Acuña, J; Cabrera García, L; Mellado Peña, M J

    2014-10-01

    In 2011, the Spanish Association of Pediatrics decided to support the most ambitious project of its newly created Committee for Medicinal Products: Pediamécum. This is the first free on-line database with information on medicinal products for pediatric use in Spain. The web page http://pediamecum.es/ started on December 17 December 2012. One year later, Pediamécum includes 580 registered drugs. The website achieved more than one million page views by the end of 2013. Because of the first anniversary of Pediamécum, a survey was performed to request the feeling of users. Four hundred eighty-three responses were obtained. Ninety-five percent believed that it is easy to navigate through the web, and 74% said that their doubts about the use of medicines in children were always resolved. The overall rating of Pediamécum is 7.5/10. The aims of Pediamécum are being accomplished; which is reflected essentially due to it becoming a useful tool for all professionals who care for children in their daily clinical practice. PMID:24857432

  1. A Detailed Record of Archean Biogochemical Cycles and Seawater Chemistry Preserved in Black Shales of the Abitibi Greenstone Belt

    NASA Astrophysics Data System (ADS)

    Scott, C.; Planavsky, N. J.; Bates, S. M.; Wing, B. A.; Lyons, T. W.

    2011-12-01

    Geological and biological evolution are intimately linked within the Earth System through the medium of seawater. Thus, in order to track the co-evolution of Life and Earth during the Archean Eon we must determine how biogeochemical cycles responded to and initiated changes in the composition of Archean seawater. Among our best records of biogeochemical cycles and seawater chemistry are organic carbon-rich black shales. Here we present a detailed multi-proxy study of 2.7 Ga black shales from the Abitibi Greenstone Belt, Canada. Abitibi shales demonstrate extreme enrichments in total organic carbon (up to 15 wt. %) and total sulfur (up to 6 wt. %) reflecting vigorous biogeochemical cycling in the basin, likely driven by cyanobacteria. The speciation of reactive Fe minerals indicates that pyrite formed in a sulfidic water column (euxinia) and that dissolved Fe was the limiting reactant. The deposition of more than 50 m of euxinic black shales suggests that the Fe-rich conditions reflected by Archean BIF deposition were not necessarily ubiquitous. Biologically significant trace metals fall into two categories. Metals that can be delivered to seawater in large quantities from hydrothermal sources (e.g., Cu and Zn) are enriched in the shales, reflecting their relative abundance in seawater. Conversely, metals that are primarily delivered to the ocean during oxidative weathering of the continents (e. g., Mo and V) are largely absent from the shales, reflecting depleted seawater inventories. Thus, trace metal supply at 2.7 Ga was still dominated by geological processes. Biological forcing of trace metal inventories, through oxidative weathering of the continents, was not initiated until 2.5 Ga, when Mo enrichments are first observed in the Mt. McRae Shale, Hamersley Basin. Multiple sulfur isotope analysis (32S, 33S, 34S) of disseminated pyrite displays large mass independent fractionations (Δ33S up to 6 %) reflecting a sulfur cycle dominated by atmospheric processes

  2. Biomarker Record From the Tisdale Group (2707 - 2705 Ma) and Porcupine Group (2685 - 2673 Ma) of the Abitibi Subprovidence, Timmins, Ontario, Canada

    NASA Astrophysics Data System (ADS)

    Ventura, G. T.; Kenig, F.

    2004-12-01

    Saturated/unsaturated and aromatic hydrocarbon fractions extracted from greenshist facies metasedimentary greywackes, siltstones, and shales of the Tisdale (2707-2705 Ma) and Porcupine Group (2685-2673 Ma) of the Abitibi Subprovince, Ontario Canada were analyzed for biomarkers. Core and hand samples were obtained from three mines run by Porcupine Joint Ventures and the core library at the Ministry of Northern Development and Mines, Timmins, Ontario. Tisdale Group sedimentary facies were previously interpreted as laminated massive sulfide and/or interflow sediments interstratified by subaqueous komatitic-tholeiitic flows. Porcupine Group turbidite facies were interstratified by massive, brecciated alkaline lava flows and reworked volcaniclastic facies. All Porcupine Group samples contained primary depositional fabric. Biomarker maturity calculations indicate the sediments are mature and either reached or surpassed oil generation. All samples contained hopanes C27 22,29,30-trisnorhopane-II (Ts & Tm), C29 α β -30-norhopane, C29 18α -30-norneohopane, C{30 } α β hopane, C30 β α - hopane, and C31-C35 (22S & R) homohopanes. Most samples contained C27-C29 (20S & R) β α diacholestane, C27-C29 α β β cholestane (20S & R), C27-C29 α α α cholestane (20S & R), and 4-methyl steroids. Tricyclic terpanes ranging from C19-C29, but were not present in all samples. Biomarkers from the Tisdale Group samples are similar to those found in modern hydrothermal systems and include unresolved complex mixtures, abundant branched alkanes with quaternary carbon atoms, alkyl-cyclohexanes (C16-C29 with strong odd over even dominance), alkyl-cyclopentanes (C16-C29) containing only even carbon number homologs), and C37-C40 acyclic and cyclic archeal isoprenoids. Biomarkers from the Porcupine Group samples include C16-C35, branched alkanes, C16-C29 alkyl-cyclohexanes and alkyl-cyclopentanes (with no carbon number preference). Aromatic fraction for this group were generally low and

  3. Generalized Jaynes-Cummings model as a quantum search algorithm

    SciTech Connect

    Romanelli, A.

    2009-07-15

    We propose a continuous time quantum search algorithm using a generalization of the Jaynes-Cummings model. In this model the states of the atom are the elements among which the algorithm realizes the search, exciting resonances between the initial and the searched states. This algorithm behaves like Grover's algorithm; the optimal search time is proportional to the square root of the size of the search set and the probability to find the searched state oscillates periodically in time. In this frame, it is possible to reinterpret the usual Jaynes-Cummings model as a trivial case of the quantum search algorithm.

  4. Cummings and Mascato Soft on Woodcock-Johnson.

    ERIC Educational Resources Information Center

    Thompson, Pamela L.; Brassard, Marla R.

    1984-01-01

    This critique, of Cummings and Moscato's review (TM 508 777) of the Woodcock-Johnson Tests of Cognitive Ability (WJTCA) argues that the WJTCA is biased toward achievement resulting in a discrepancy of scores for learning disabled students. This bias is incompatible with the aptitude/achievement discrepancy model of specific learning disabilities.…

  5. Quantum entangled supercorrelated states in the Jaynes-Cummings model

    NASA Astrophysics Data System (ADS)

    Rajagopal, A. K.; Jensen, K. L.; Cummings, F. W.

    1999-08-01

    The regions of independent quantum states, maximally classically correlated states, and purely quantum entangled (supercorrelated) states described in a recent formulation of quantum information theory by Cerf and Adami are explored here numerically in the parameter space of the well-known exactly soluble Jaynes-Cummings model for equilibrium and nonequilibrium time-dependent ensembles.

  6. The Library and Information Science CumIndex.

    ERIC Educational Resources Information Center

    Kilgour, Frederick G.

    The "CumIndex" cumulates the back-of-book indexes of 96 English-language works in the field of library and information science and thus provides an in-depth index to important works in the field. The list is the result of a sequence of computer programs which edit, modify, and reorganize index entries from individual books to provide a coherent…

  7. [Advance in studies on neuroprotective mechanism of Uncariae Ramulus Cum Uncis].

    PubMed

    Wei, Fang-Fang; Zeng, Chang-Qing; Zhao, Yu-Hong; Liu, Lin

    2014-07-01

    The Uncariae Ramulus Cum Uncis is a commonly used traditional Chinese medicine. In recent years, many studies have revealed its prominent neuroprotection function. The active ingredients in Uncariae Ramulus Cum Uncis could protect the nervous system in a multi-path and multi-target manner. Uncariae Ramulus Cum Uncis shows the neuroprotective effect by resisting oxidation, scavenging free radicals, modulating neurotransmitters and their related receptors, regulating the inflammatory factors and their related pathways, attenuating neuron apoptosis, reducing intracellular Ca2+ overloads and mitigating neurodegeneration. In this paper, the authors summarized the advance in studies on neuroprotective mechanisms of Uncariae Ramulus Cum Uncis. PMID:25272481

  8. cumA, a Gene Encoding a Multicopper Oxidase, Is Involved in Mn2+ Oxidation in Pseudomonas putida GB-1

    PubMed Central

    Brouwers, Geert-Jan; de Vrind, Johannes P. M.; Corstjens, Paul L. A. M.; Cornelis, Pierre; Baysse, Christine; de Vrind-de Jong, Elisabeth W.

    1999-01-01

    Pseudomonas putida GB-1-002 catalyzes the oxidation of Mn2+. Nucleotide sequence analysis of the transposon insertion site of a nonoxidizing mutant revealed a gene (designated cumA) encoding a protein homologous to multicopper oxidases. Addition of Cu2+ increased the Mn2+-oxidizing activity of the P. putida wild type by a factor of approximately 5. The growth rates of the wild type and the mutant were not affected by added Cu2+. A second open reading frame (designated cumB) is located downstream from cumA. Both cumA and cumB probably are part of a single operon. The translation product of cumB was homologous (level of identity, 45%) to that of orf74 of Bradyrhizobium japonicum. A mutation in orf74 resulted in an extended lag phase and lower cell densities. Similar growth-related observations were made for the cumA mutant, suggesting that the cumA mutation may have a polar effect on cumB. This was confirmed by site-specific gene replacement in cumB. The cumB mutation did not affect the Mn2+-oxidizing ability of the organism but resulted in decreased growth. In summary, our data indicate that the multicopper oxidase CumA is involved in the oxidation of Mn2+ and that CumB is required for optimal growth of P. putida GB-1-002. PMID:10103278

  9. Dissipative two-mode Tavis-Cummings model with time-delayed feedback control

    NASA Astrophysics Data System (ADS)

    Kopylov, Wassilij; Radonjić, Milan; Brandes, Tobias; Balaž, Antun; Pelster, Axel

    2015-12-01

    We investigate the dynamics of a two-mode laser system by extending the two-mode Tavis-Cummings model with dissipative channels and incoherent pumping and by applying the mean-field approximation in the thermodynamic limit. To this end we analytically calculate up to four possible nonequilibrium steady states (fixed points) and determine the corresponding complex phase diagram. Various possible phases are distinguished by the actual number of fixed points and their stability. In addition, we apply three time-delayed Pyragas feedback control schemes. Depending on the time delay and the strength of the control term, this can lead to the stabilization of unstable fixed points or to the selection of a particular cavity mode that is macroscopically occupied.

  10. Negativity as entanglement degree of the Jaynes Cummings model

    NASA Astrophysics Data System (ADS)

    Akhtarshenas, S. J.; Farsi, M.

    2007-05-01

    In this paper, by using the notion of negativity, we study the degree of entanglement of a two-level atom interacting with a quantized radiation field, described by the Jaynes-Cummings model (JCM). We suppose that initially the field is in a pure state and the atom is in a general mixed state. In this case the negativity fully captures the entanglement of the JCM. We investigate the case that the initial state of the field is a coherent state. The influences of the detuning on the degree of entanglement are also examined.

  11. Conditional nonlinear operations by sequential Jaynes-Cummings interactions

    NASA Astrophysics Data System (ADS)

    Park, Kimin; Marek, Petr; Filip, Radim

    2016-07-01

    Nonlinear operations are essential for quantum information processing. We propose a way of implementing a class of nonlinear operations by sequential application of conditional gates based on Jaynes-Cummings (JC) interaction and projective measurements. The scheme has many advantages over the previously proposed all-optical methods and can be applied in several available experimental platforms, such as cavity quantum electrodynamics, trapped ions, and others. We demonstrate performance of the approach on the example of the cubic nonlinearity. We show several different ways in which the full nonlinear operation can be decomposed into sequences of the individual gates, and we compare their performance.

  12. Entanglement invariant for the double Jaynes-Cummings model

    SciTech Connect

    Sainz, Isabel; Bjoerk, Gunnar

    2007-10-15

    We study entanglement dynamics between four qubits interacting through two isolated Jaynes-Cummings Hamiltonians, via an entanglement measure based on the wedge product. We compare the results with similar results obtained using bipartite concurrence resulting in what is referred to as 'entanglement sudden death'. We find a natural entanglement invariant under evolution, demonstrating that entanglement spreads out over all of the system's degrees of freedom that become entangled through the interaction. We also provide an analysis of why certain initial states lose all their entanglement in a finite time, although their excitation and coherence vanish only asymptotically with time.

  13. 40 CFR 90.708 - Cumulative Sum (CumSum) procedure.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... i −1+X i−(FEL+F))] Where: Ci=The current CumSum statistic. Ci -1=The previous CumSum statistic... individual engine. FEL=Family Emission Limit (the standard if no FEL). F=.25×σ. (2) After each test pursuant... configuration, or the use of a different deterioration factor) with no changes to the FEL (where...

  14. 40 CFR 90.708 - Cumulative Sum (CumSum) procedure.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... i −1+X i−(FEL+F))] Where: Ci=The current CumSum statistic. Ci -1=The previous CumSum statistic... individual engine. FEL=Family Emission Limit (the standard if no FEL). F=.25×σ. (2) After each test pursuant... configuration, or the use of a different deterioration factor) with no changes to the FEL (where...

  15. 40 CFR 90.708 - Cumulative Sum (CumSum) procedure.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... i -1+X i−(FEL+F))] Where: Ci=The current CumSum statistic. Ci -1=The previous CumSum statistic... individual engine. FEL=Family Emission Limit (the standard if no FEL). F=.25×σ. (2) After each test pursuant... configuration, or the use of a different deterioration factor) with no changes to the FEL (where...

  16. 40 CFR 90.708 - Cumulative Sum (CumSum) procedure.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... i -1+X i−(FEL+F))] Where: Ci=The current CumSum statistic. Ci -1=The previous CumSum statistic... individual engine. FEL=Family Emission Limit (the standard if no FEL). F=.25×σ. (2) After each test pursuant... configuration, or the use of a different deterioration factor) with no changes to the FEL (where...

  17. 40 CFR 90.708 - Cumulative Sum (CumSum) procedure.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... i −1+X i−(FEL+F))] Where: Ci=The current CumSum statistic. Ci -1=The previous CumSum statistic... individual engine. FEL=Family Emission Limit (the standard if no FEL). F=.25×σ. (2) After each test pursuant... configuration, or the use of a different deterioration factor) with no changes to the FEL (where...

  18. Performance equations of a collector cum storage system using phase change materials

    SciTech Connect

    Bansal, N.K. ); Buddhi, D. )

    1992-01-01

    A thermal analysis has been developed for a collector cum system for quasi-steady-state conditions using phase change materials. Performance equations of the Hottel-Whillier-Bliss type for flat-plate collector cum storage system have been obtained. Calculations have been performed for a wide range of parameters to investigate the applicability of the developed mathematical model.

  19. Coordination of peroxide to the CuM center of peptidylglycine α-hydroxylating monooxygenase (PHM): structural and computational study

    PubMed Central

    Rudzka, Katarzyna; Moreno, Diego M.; Eipper, Betty; Mains, Richard; Estrin, Dario A.

    2014-01-01

    Many bioactive peptides, such as hormones and neuropeptides, require amidation at the C terminus for their full biological activity. Peptidylglycine α-hydroxylating monooxygenase (PHM) performs the first step of the amidation reaction—the hydroxylation of peptidylglycine substrates at the Cα position of the terminal glycine. The hydroxylation reaction is copper- and O2-dependent and requires 2 equiv of exogenous reductant. The proposed mechanism suggests that O2 is reduced by two electrons, each provided by one of two nonequivalent copper sites in PHM (CuH and CuM). The characteristics of the reduced oxygen species in the PHM reaction and the identity of the reactive intermediate remain uncertain. To further investigate the nature of the key intermediates in the PHM cycle, we determined the structure of the oxidized form of PHM complexed with hydrogen peroxide. In this 1.98-Å-resolution structure (hydro)peroxide binds solely to CuM in a slightly asymmetric side-on mode. The O–O interatomic distance of the copper-bound ligand is 1.5 Å, characteristic of peroxide/hydroperoxide species, and the Cu–O distances are 2.0 and 2.1 Å. Density functional theory calculations using the first coordination sphere of the CuM active site as a model system show that the computed energies of the side-on L3CuM(II)–O22− species and its isomeric, end-on structure L3CuM(I)–O2·− are similar, suggesting that both these intermediates are significantly populated within the protein environment. This observation has important mechanistic implications. The geometry of the observed side-on coordinated peroxide ligand in L3CuM(II)O22− is in good agreement with the results of a hybrid quantum mechanical–molecular mechanical optimization of this species. PMID:23247335

  20. Quantum Computation with the Jaynes-Cummings Model

    NASA Astrophysics Data System (ADS)

    Azuma, H.

    2011-09-01

    In this paper, we propose a method for building a two-qubit gate with the Jaynes-Cummings model (JCM). In our scheme, we construct a qubit from a pair of optical paths where a photon is running. Generating Knill, Laflamme and Milburn's nonlinear sign-shift gate by the JCM, we construct the conditional sign-flip gate, which works with small error probability in principle. We also discuss two experimental setups for realizing our scheme. In the first experimental setup, we make use of coherent lights to examine whether or not our scheme works. In the second experimental setup, an optical loop circuit made out of the polarizing beam splitter and the Pockels cell takes an important role in the cavity.

  1. Entropy exchange and entanglement in the Jaynes-Cummings model

    NASA Astrophysics Data System (ADS)

    Boukobza, E.; Tannor, D. J.

    2005-06-01

    The Jaynes-Cummings model (JCM) is the simplest fully quantum model that describes the interaction between light and matter. We extend a previous analysis by Phoenix and Knight [Ann. Phys. 186, 381 (1988)] of the JCM by considering mixed states of both the light and matter. We present examples of qualitatively different entropic correlations. In particular, we explore the regime of entropy exchange between light and matter, i.e., where the rate of change of the two are anticorrelated. This behavior contrasts with the case of pure light-matter states in which the rate of change of the two entropies are positively correlated and in fact identical. We give an analytical derivation of the anticorrelation phenomenon and discuss the regime of its validity. Finally, we show a strong correlation between the region of the Bloch sphere characterized by entropy exchange and that characterized by minimal entanglement as measured by the negative eigenvalues of the partially transposed density matrix.

  2. Oscillator-like coherent states for the Jaynes-Cummings Model

    NASA Technical Reports Server (NTRS)

    Berubelauziere, Y.; Hussin, V.; Nieto, Michael M.

    1995-01-01

    A new way of diagonalizing the Jaynes-Cummings Hamiltonian is proposed, which allows the definition of annihilation operators and coherent states for this model. Mean values and dispersions over these states are computed and interpreted.

  3. Partial entangling power for the Jaynes-Cummings model

    NASA Astrophysics Data System (ADS)

    Xiong, Heng-Na; Lu, Xiao-Ming; Wang, Xiaoguang

    2012-01-01

    Partial entangling power provides the average amount of entanglement produced by a d1 × d2 bipartite unitary operator. The average is done over the initial distribution of the states of one of the subsystems. In this paper, we extend the expression of the partial entangling power to the case that d1 is finite and d2 is arbitrary. In particular, we give an explicit expression of partial entangling power for the 2 × ∞ system. The expression can be well applicable to the Jaynes-Cummings model (JCM). The results can recover the well-known phenomenon in the JCM. We explicitly discuss its behaviour in the large detuning case and at the resonance case. Comparing the two cases, we find that it is easier for the JCM in the large detuning case to reach and maintain its maximum entangling power, while for the JCM at resonance, the achievable maximum entangling power is larger. In addition, the time average partial entangling power is also discussed.

  4. From the Jaynes-Cummings-Hubbard to the Dicke model

    NASA Astrophysics Data System (ADS)

    Schmidt, S.; Blatter, G.; Keeling, J.

    2013-11-01

    We discuss the Jaynes-Cummings-Hubbard model describing the superfluid-Mott insulator transition of polaritons (i.e., dressed photon-qubit states) in coupled qubit-cavity arrays in the crossover from strong to weak correlations. In the strongly correlated regime the phase diagram and the elementary excitations of lattice polaritons near the Mott lobes are calculated analytically using a slave-boson theory (SBT). The opposite regime of weakly interacting polariton superfluids is described by a weak-coupling mean-field theory for a generalized multi-mode Dicke model. We show that a remarkable relation between the two theories exists in the limit of large photon bandwidth and large negative detuning, i.e., when the nature of polariton quasiparticles becomes qubit-like. In this regime, the weak-coupling theory predicts the existence of a single Mott lobe with a change of the universality class of the phase transition at the tip of the lobe, in perfect agreement with the SBT. Moreover, the spectra of low energy excitations, i.e., the sound velocity of the Goldstone mode and the gap of the amplitude mode match exactly as calculated from both theories.

  5. cumA, a gene encoding a multicopper oxidase, is involved in Mn{sup 2+} oxidation in Pseudomonas putida GB-1

    SciTech Connect

    Brouwers, G.J.; Vrind, J.P.M. de; Corstjens, P.L.A.M.; Vrind-de Jong, E.W. de; Cornelis, P.; Baysse, C.

    1999-04-01

    Pseudomonas putida GB-1-002 catalyzes the oxidation of Mn{sup 2+}. Nucleotide sequence analysis of the transposon insertion site of a nonoxidizing mutant revealed a gene (designated cumA) encoding a protein homologous to multicopper oxidases. Addition of Cu{sup 2+} increased the Mn{sup 2+}-oxidizing activity of the P. putida wild type by a factor of approximately 5. The growth rates of the wild type and the mutant were not affected by added Cu{sup 2+}. A second open reading frame (designated cumB) is located downstream from cumA. Both cumA and cumB probably are part of a single operon. The translation product of cumB was homologous to that of orf74 of Bradyrhizobium japonicum. A mutation in orf74 resulted in an extended lag phase and lower cell densities. Similar growth-related observations were made for the cumA mutant, suggesting that the cumA mutation may have a polar effect on cumB. This was confirmed by site-specific gene replacement in cumB. The cumB mutation did not affect the Mn{sup 2+}-oxidizing ability of the organism but resulted in decreased growth. In summary, the data indicate that the multicopper oxidase CumA is involved in the oxidation of Mn{sup 2+} and that CumB is required for optimal growth of P. putida GB-1-002.

  6. Parenting in a Broader Context: A Reply to Emery, Fincham, and Cummings (1992).

    ERIC Educational Resources Information Center

    Fauber, Robert L.; Long, Nicholas

    1992-01-01

    Responds to comments made in previous article by Emery, Fincham, and Cummings concerning Fauber and Long's (1991) discussion of family's role in child psychotherapy. Attempts to clarify areas of possible confusion, including meaning of "contextual variables," parenting as appropriate focus of treatment, assumptions about what is meant by…

  7. 40 CFR 91.508 - Cumulative Sum (CumSum) procedure.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... = 0 (i.e. C0 = 0) Xi = The current emission test result for an individual engine FEL = Family Emission... different deterioration factor) with no changes to the FEL, all previous sample size and CumSum statistic... § 91.122 by modifying its FEL as a result of an engine family modification, the manufacturer...

  8. 40 CFR 91.508 - Cumulative Sum (CumSum) procedure.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... = 0 (i.e. C0 = 0) Xi = The current emission test result for an individual engine FEL = Family Emission... different deterioration factor) with no changes to the FEL, all previous sample size and CumSum statistic... § 91.122 by modifying its FEL as a result of an engine family modification, the manufacturer...

  9. 40 CFR 91.508 - Cumulative Sum (CumSum) procedure.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... = 0 (i.e. C0 = 0) Xi = The current emission test result for an individual engine FEL = Family Emission... different deterioration factor) with no changes to the FEL, all previous sample size and CumSum statistic... § 91.122 by modifying its FEL as a result of an engine family modification, the manufacturer...

  10. 40 CFR 91.508 - Cumulative Sum (CumSum) procedure.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... = 0 (i.e. C0 = 0) Xi = The current emission test result for an individual engine FEL = Family Emission... different deterioration factor) with no changes to the FEL, all previous sample size and CumSum statistic... § 91.122 by modifying its FEL as a result of an engine family modification, the manufacturer...

  11. 40 CFR 91.508 - Cumulative Sum (CumSum) procedure.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... = 0 (i.e. C0 = 0) Xi = The current emission test result for an individual engine FEL = Family Emission... different deterioration factor) with no changes to the FEL, all previous sample size and CumSum statistic... § 91.122 by modifying its FEL as a result of an engine family modification, the manufacturer...

  12. Tavis-Cummings model and collective multiqubit entanglement in trapped ions

    SciTech Connect

    Retzker, A.; Solano, E.; Reznik, B.

    2007-02-15

    We present a method of generating collective multiqubit entanglement via global addressing of an ion chain performing blue and red Tavis-Cummings interactions, where several qubits are coupled to a collective motional mode. We show that a wide family of Dicke states and irradiant states can be generated by single global laser pulses, unitarily or helped with suitable postselection techniques.

  13. CUM LAUDE: A New Approach in Designing Computer-Assisted Language Programs.

    ERIC Educational Resources Information Center

    Urion, Henry K.

    CUM LAUDE (Computerized Understanding of Morphology--Language Acquisition under Development in Education) is a unique attempt to develop a system of computer programs enabling a machine to "understand" the grammatical relationships between the various parts of speech in a natural language. In response to an analysis of current computer-assisted…

  14. Hepatoprotective effects of hoveniae semen cum fructus extracts in ethanol intoxicated mice

    PubMed Central

    Cho, Ilje; Kim, Joowan; Jung, Jaijun; Sung, Soohyun; Kim, Jongkyu; Lee, Namju; Ku, Saekwang

    2016-01-01

    [Purpose] The objective of this study was to evaluate the hepatoprotective effects of Hoveniae Semen Cum Fructus extract in ethanol induced hepatic damages. [Methods] Hepatic damages were induced by oral administration of ethanol and then Hoveniae Semen Cum Fructus extract was administered. [Results] Following Hoveniae Semen Cum Fructus extract administration, body and liver weights were increased, while aspartate aminotransferase, alanine aminotransferase, albumin, γ-glutamyl transferase, and triglyceride levels in the serum, triglyceride contents, tumor necrosis factor -α level, cytochrome (CY) P450 2E1 activity in the liver and mRNA expression of hepatic lipogenic genes, and Nitrotyrosine and 4-HNE-immunolabelled hepatocytes were decreased. However, mRNA expression of genes involved in fatty acid oxidation was increased. Also, as a protective mechanism for hepatic antioxidant defense systems, decreased liver MDA contents, increased glutathione contents, increased dismutase and catalase activities were observed when compared to the ethanol control. [Conclusion] Hoveniae Semen Cum Fructus extract favorably protected against liver damages, mediated by its potent anti-inflammatory and anti-steatosis properties through the augmentation of the hepatic antioxidant defense system by NF-E2-related factor-2 activation, and down-regulation of the mRNA expression of hepatic lipogenic genes or up-regulation of the mRNA expression of genes involved in fatty acid oxidation. PMID:27298813

  15. Quantum and classical chaos in kicked coupled Jaynes-Cummings cavities

    SciTech Connect

    Hayward, A. L. C.; Greentree, Andrew D.

    2010-06-15

    We consider two Jaynes-Cummings cavities coupled periodically with a photon hopping term. The semiclassical phase space is chaotic, with regions of stability over some ranges of the parameters. The quantum case exhibits dynamic localization and dynamic tunneling between classically forbidden regions. We explore the correspondence between the classical and quantum phase space and propose an implementation in a circuit QED system.

  16. A Stylistic Study on the Linguistic Deviations in E. E. Cummings' Poetry

    ERIC Educational Resources Information Center

    Li, Xin; Shi, Mengchen

    2015-01-01

    Regarded as the pioneer of experimental poetry, E. E. Cummings' unconventional treatment of poetic language has reached an unprecedented acme, which has intrigued and baffled numerous scholars, researchers and readers alike. Nevertheless, the very existence of poetry, like other types of literary texts, demonstrates the significance and value of…

  17. Sulfur isotope and trace element data from ore sulfides in the Noranda district (Abitibi, Canada): implications for volcanogenic massive sulfide deposit genesis

    NASA Astrophysics Data System (ADS)

    Sharman, Elizabeth R.; Taylor, Bruce E.; Minarik, William G.; Dubé, Benoît; Wing, Boswell A.

    2015-06-01

    We examine models for volcanogenic massive sulfide (VMS) mineralization in the ~2.7-Ga Noranda camp, Abitibi subprovince, Superior Province, Canada, using a combination of multiple sulfur isotope and trace element data from ore sulfide minerals. The Noranda camp is a well-preserved, VMS deposit-rich area that is thought to represent a collapsed volcanic caldera. Due to its economic value, the camp has been studied extensively, providing a robust geological framework within which to assess the new data presented in this study. We explore previously proposed controls on mineralization within the Noranda camp and, in particular, the exceptional Au-rich Horne and Quemont deposits. We present multiple sulfur isotope and trace element compositional data for sulfide separates representing 25 different VMS deposits and "showings" within the Noranda camp. Multiple sulfur isotope data for this study have δ34SV-CDT values of between -1.9 and +2.5 ‰, and Δ33SV-CDT values of between -0.59 and -0.03 ‰. We interpret the negative Δ33S values to be due to a contribution of sulfur that originated as seawater sulfate to form the ore sulfides of the Noranda camp VMS deposits. The contribution of seawater sulfate increased with the collapse and subsequent evolution of the Noranda caldera, an inference supported by select trace and major element analyses. In particular, higher concentrations of Se occur in samples with Δ33S values closer to 0 ‰, as well as lower Fe/Zn ratios in sphalerite, suggesting lower pressures and temperatures of formation. We also report a relationship between average Au grade and Δ33S values within Au-rich VMS deposits of the Noranda camp, whereby higher gold grades are associated with near-zero Δ33S values. From this, we infer a dominance of igneous sulfur in the gold-rich deposits, either leached from the volcanic pile and/or directly degassed from an associated intrusion.

  18. Tracing sources of crustal contamination using multiple S and Fe isotopes in the Hart komatiite-associated Ni-Cu-PGE sulfide deposit, Abitibi greenstone belt, Ontario, Canada

    NASA Astrophysics Data System (ADS)

    Hiebert, R. S.; Bekker, A.; Houlé, M. G.; Wing, B. A.; Rouxel, O. J.

    2016-03-01

    Assimilation by mafic to ultramafic magmas of sulfur-bearing country rocks is considered an important contributing factor to reach sulfide saturation and form magmatic Ni-Cu-platinum group element (PGE) sulfide deposits. Sulfur-bearing sedimentary rocks in the Archean are generally characterized by mass-independent fractionation of sulfur isotopes that is a result of atmospheric photochemical reactions, which produces isotopically distinct pools of sulfur. Likewise, low-temperature processing of iron, through biological and abiotic redox cycling, produces a range of Fe isotope values in Archean sedimentary rocks that is distinct from the range of the mantle and magmatic Fe isotope values. Both of these signals can be used to identify potential country rock assimilants and their contribution to magmatic sulfide deposits. We use multiple S and Fe isotopes to characterize the composition of the potential iron and sulfur sources for the sulfide liquids that formed the Hart deposit in the Shaw Dome area within the Abitibi greenstone belt in Ontario (Canada). The Hart deposit is composed of two zones with komatiite-associated Ni-Cu-PGE mineralization; the main zone consists of a massive sulfide deposit at the base of the basal flow in the komatiite sequence, whereas the eastern extension consists of a semi-massive sulfide zone located 12 to 25 m above the base of the second flow in the komatiite sequence. Low δ56Fe values and non-zero δ34S and Δ33S values of the komatiitic rocks and associated mineralization at the Hart deposit is best explained by mixing and isotope exchange with crustal materials, such as exhalite and graphitic argillite, rather than intrinsic fractionation within the komatiite. This approach allows tracing the extent of crustal contamination away from the deposit and the degree of mixing between the sulfide and komatiite melts. The exhalite and graphitic argillite were the dominant contaminants for the main zone of mineralization and the eastern

  19. cumA Multicopper Oxidase Genes from Diverse Mn(II)-Oxidizing and Non-Mn(II)-Oxidizing Pseudomonas Strains

    PubMed Central

    Francis, Chris A.; Tebo, Bradley M.

    2001-01-01

    A multicopper oxidase gene, cumA, required for Mn(II) oxidation was recently identified in Pseudomonas putida strain GB-1. In the present study, degenerate primers based on the putative copper-binding regions of the cumA gene product were used to PCR amplify cumA gene sequences from a variety of Pseudomonas strains, including both Mn(II)-oxidizing and non-Mn(II)-oxidizing strains. The presence of highly conserved cumA gene sequences in several apparently non-Mn(II)-oxidizing Pseudomonas strains suggests that this gene may not be expressed, may not be sufficient alone to confer the ability to oxidize Mn(II), or may have an alternative function in these organisms. Phylogenetic analysis of both CumA and 16S rRNA sequences revealed similar topologies between the respective trees, including the presence of several distinct phylogenetic clusters. Overall, our results indicate that both the cumA gene and the capacity to oxidize Mn(II) occur in phylogenetically diverse Pseudomonas strains. PMID:11526033

  20. Quantum state collapse and revival under the anti-Jaynes-Cummings model

    NASA Astrophysics Data System (ADS)

    Lv, Dingshun; An, Shuoming; Um, Mark; Zhang, Junhua; Zhang, Jingning; Kim, M. S.; Kim, Kihwan; CenterQuantum Information, IIIS, Tsinghua University Team

    2015-05-01

    We study the evolution of a coherent state of phonon mode by anti-Jaynes-Cummings (AJC) interaction in a trapped 171Yb+ ion system. We observe the quantum collapse and revival phenomena by measuring its Q function at the several time intervals. We measure the Q-function by detecting the probability in the vacuum state through the conventional arithmetic subtraction. We also measure the corresponding Wigner function, and observe the negativity, which clearly shows non-classical state emergence during the AJC dynamic evolution. On top of the standard AJC evolution, we introduce an additional phase or Jaynes-Cummings (JC) coupling and control and reverse the dynamics. This work was supported by the National Basic Research Program of China under Grants No. 2011CBA00300 (No. 2011CBA00301), the National Natural Science Foundation of China 11374178. M.S. Kim was supported by the UK EPSRC and Royal Society Wolfson Merit Award.

  1. Berry phase in a two-atom Jaynes-Cummings model with Kerr medium

    NASA Astrophysics Data System (ADS)

    Bu, Shen-Ping; Zhang, Guo-Feng; Liu, Jia; Chen, Zi-Yu

    2008-12-01

    The Jaynes-Cummings model (JCM) is an very important model for describing interaction between quantized electromagnetic fields and atoms in cavity quantum electrodynamics (QED). This model is generalized in many different directions since it predicts many novel quantum effects that can be verified by modern physics experimental technologies. In this paper, the Berry phase and entropy of the ground state for arbitrary photon number n of a two-atom Jaynes-Cummings model with Kerr-like medium are investigated. It is found that there is some correspondence between their images, especially the existence of a curve in the Δ-ɛ plane along which the energy, Berry phase and entropy all reach their special values. So it is available for detecting entanglement by applying Berry phase.

  2. Two-polariton bound states in the Jaynes-Cummings-Hubbard model

    SciTech Connect

    Wong, Max T. C.; Law, C. K.

    2011-05-15

    We examine the eigenstates of the one-dimensional Jaynes-Cummings-Hubbard model in the two-excitation subspace. We discover that two-excitation bound states emerge when the ratio of vacuum Rabi frequency to the tunneling rate between cavities exceeds a critical value. We determine the critical value as a function of the quasimomentum quantum number, and indicate that the bound states carry a strong correlation in which the two polaritons appear to be spatially confined together.

  3. 2D-gel based proteomics unravels neurogenesis and energetic metabolism dysfunction of the olfactory bulb in CUMS rat model.

    PubMed

    Cheng, Ke; Li, Juan; Yang, Deyu; Yang, Yongtao; Rao, Chenglong; Zhang, Shuxiao; Wang, Wei; Guo, Hua; Fang, Liang; Zhu, Dan; Han, Yu; Xie, Peng

    2016-10-15

    Major depression is a devastating psychiatric disease worldwide currently. A reduced olfactory sensitivity in MDD patients was well evidenced. We previously interrogated the mechanism of decreasing hippocampus neurogenesis in CUMS rat model of depression. The Olfactory Bulb (OB) is crucial part of the olfactory system which functions in post-developmental neurogenesis. However, the mechanism of the dysfunction of OB induced by CUMS is still largely unknown. Herein, by using the chronic unpredictable mild stress (CUMS) rat model of depression, differential protein expression between the OB proteomes of CUMS and control group was interrogated through two-dimensional electrophoresis coupling with matrix-assisted laser desorption ionization-time of flight tandem mass spectrometry. Twenty nine differential protein expression was analyzed by Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway over-representation and Ingenuity pathways analysis (IPA). Seven identified differential proteins were selected for Western blotting validation. This study provides insight that neurogenesis and Energy metabolism disorder is involved in OB dysfunction induced by CUMS. PMID:27340088

  4. Experimental investigation of a steady-state dynamical phase transition in a Jaynes-Cummings dimer

    NASA Astrophysics Data System (ADS)

    Raftery, James; Sadri, Darius; Mandt, Stephan; Tureci, Hakan; Houck, Andrew

    Experimental progress in circuit-QED has made it possible to study non-equilibrium many-body physics using strongly correlated photons. Such open and driven systems can display new types of dynamical phase transitions. A steady state transition has also been predicted for a Jaynes-Cummings dimer where the photon current between the two cavities acts as an order parameter. Here, we discuss the theory and report measurements of the steady-state behavior of a circuit-QED dimer with in situ tunable inter-cavity coupling and on-site photon-photon interaction. Recently deceased.

  5. Dynamics of Jaynes-Cummings Model in the Absence of Rotating-Wave Approximation

    NASA Astrophysics Data System (ADS)

    Fan, Yun-Xia; Liu, Tao; Feng, Mang; Wang, Ke-Lin

    2007-05-01

    The Jaynes-Cummings model (JCM) is studied in the absence of the rotating-wave approximation (RWA) by a coherent-state expansion technique. In comparison with the previous paper in which the coherent-state expansion was performed only to the third order, we carry out in this paper a complete expansion to demonstrate exactly the dynamics of the JCM without the RWA. Our study gives a systematic method to solve the non-RWA problem, which would be useful in various physical systems, e.g., in a system with an ultracold trapped ion experiencing the running waves of lasers.

  6. Atom-field entanglement in the Jaynes-Cummings model without rotating wave approximation

    NASA Astrophysics Data System (ADS)

    Mirzaee, M.; Batavani, M.

    2015-04-01

    In this paper, we present a structure for obtaining the exact eigenfunctions and eigenvalues of the Jaynes-Cummings model (JCM) without the rotating wave approximation (RWA). We study the evolution of the system in the strong coupling region using the time evolution operator without RWA. The entanglement of the system without RWA is investigated using the Von Neumann entropy as an entanglement measure. It is interesting that in the weak coupling regime, the population of the atomic levels and Von Neumann entropy without RWA model shows a good agreement with the RWA whereas in strong coupling domain, the results of these two models are quite different.

  7. The f-deformed Jaynes-Cummings model and its nonlinear coherent states

    NASA Astrophysics Data System (ADS)

    de los Santos-Sánchez, O.; Récamier, J.

    2012-01-01

    Based on the f-oscillator formalism, we introduce a nonlinear Jaynes-Cummings model (NJCM) which is constructed from the standard JCM by deforming the single-mode field operators. Such a generalization of the JCM describes the interaction of a two-level atom with a single mode of the electromagnetic field in the presence of a nonlinear Kerr-like medium. Since the medium is modelled as an f-oscillator, it is possible to consider the field f-coherent states (nonlinear coherent states) and their evolution.

  8. Two-Photon Jaynes-Cummings Model Governed by Milburn Equation with Phase Damping

    NASA Astrophysics Data System (ADS)

    Chen, Chang-Yong; Li, Shao-Hua; Liu, Zong-Liang

    2006-04-01

    In this paper, we find an analytic solution of the master equation of a non-resonant two-photon Jaynes-Cummings model (JCM) with phase damping with the help of the super-operator technique. We study the influence of phase damping on non-classical effects in the JCM, such as oscillations of the photon-number distribution, revivals of the atomic inversion, and sub-Possion photon statistics. It is demonstrated that the phase damping suppresses the revivals of the atomic inversion and non-classical effects of the cavity field in the JCM.

  9. Cavity losses for the dissipative Jaynes Cummings Hamiltonian beyond rotating wave approximation

    NASA Astrophysics Data System (ADS)

    Scala, M.; Militello, B.; Messina, A.; Maniscalco, S.; Piilo, J.; Suominen, K.-A.

    2007-11-01

    A microscopic derivation of the master equation for the Jaynes-Cummings model with cavity losses is given, taking into account the terms in the dissipator which vary with frequencies of the order of the vacuum Rabi frequency. Our approach allows us to single out physical contexts wherein the usual phenomenological dissipator turns out to be fully justified and constitutes an extension of our previous analysis (Scala et al 2007 Phys. Rev. A 75 013811), where a microscopic derivation was given in the framework of the rotating wave approximation.

  10. Improved exponential product cum dual to product type estimator of population mean

    NASA Astrophysics Data System (ADS)

    Singh, B. K.; Choudhury, Sanjib; Kumar, Abhishek

    2013-09-01

    In the present paper, an efficient exponential product cum dual to product type estimator has been proposed to estimate the population mean of the study variable by using simple random sampling scheme. The bias and mean squared error of the proposed estimator have been obtained up to the first order of approximation. A comparison has been made with existing similar estimators. The estimator has shown its efficiency over other estimators in terms of mean squared error (MSE). The numerical demonstrations have been made to show the gain in the estimator under study.

  11. Vacuum-induced Berry phases in single-mode Jaynes-Cummings models

    SciTech Connect

    Liu, Yu; Wei, L. F.; Jia, W. Z.; Liang, J. Q.

    2010-10-15

    Motivated by work [Phys. Rev. Lett. 89, 220404 (2002)] for detecting the vacuum-induced Berry phases with two-mode Jaynes-Cummings models (JCMs), we show here that, for a parameter-dependent single-mode JCM, certain atom-field states also acquired photon-number-dependent Berry phases after the parameter slowly changed and eventually returned to its initial value. This geometric effect related to the field quantization still exists, even if the field is kept in its vacuum state. Specifically, a feasible Ramsey interference experiment with a cavity quantum electrodynamics system is designed to detect the vacuum-induced Berry phase.

  12. Bistability effect in the extreme strong coupling regime of the Jaynes-Cummings model

    NASA Astrophysics Data System (ADS)

    Dombi, András; Vukics, András; Domokos, Peter

    2015-03-01

    We study the nonlinear response of a driven cavity QED system in the extreme strong coupling regime where the saturation photon number is below one by many orders of magnitude. In this regime, multi-photon resonances within the Jaynes-Cummings spectrum up to high order can be resolved. We identify an intensity and frequency range of the external coherent drive for which the system exhibits bistability instead of resonant multi-photon transitions. The cavity field evolves into a mixture of the vacuum and another quasi-classical state well separated in phase space. The corresponding time evolution of the outgoing intensity is a telegraph signal alternating between two attractors.

  13. From closed ranks to open doors: Elaine and John Cummings' mental health education experiment in 1950s Saskatchewan.

    PubMed

    Kendall, Kathleen

    2011-01-01

    During late 1951 and early 1952, married couple, social biologist Elaine Cumming and psychiatrist John Cumming, led a mental health education experiment in Indian Head, Saskatchewan. The study, which was intended to inform strategies toward deinstitutionalization, sought to determine if attitudes regarding mental illness could be changed through commonly used educational practices. It was shaped by the shared interests of powerful philanthropic, charitable, psychiatric, academic and governmental bodies to create healthier citizens and a stronger democratic nation through expert knowledge. However, in addition to the disappointing findings indicating that attitudes remained unchanged, the town appeared to close ranks against the research team. Nonetheless, the Cummings' later association with sociologists at Harvard University enabled them to interpret the results in a way that lent the study credibility and themselves legitimacy, thus opening the door to their careers as very successful researchers and policy-makers. PMID:22514867

  14. Entanglement and the Jaynes-Cummings model with Rydberg-dressed atoms

    NASA Astrophysics Data System (ADS)

    Biedermann, Grant

    2016-05-01

    Controlling quantum entanglement between parts of a many-body system is the key to unlocking the power of quantum information processing for applications such as quantum computation, high-precision sensing, and simulation of many-body physics. Spin degrees of freedom of ultracold neutral atoms in their ground electronic state provide a natural platform given their long coherence times and our ability to control them with magneto-optical fields, but creating strong coherent coupling between spins has been challenging. We demonstrate for the first time a strong and tunable Rydberg-dressed interaction between spins of individually trapped cesium atoms with energy shifts of order 1 MHz in units of Planck's constant. We spectroscopically demonstrate that this system is isomorphic to a Jaynes-Cummings Hamiltonian, and observe the √{ N} nonlinearity of the Jaynes-Cummings ladder with a single symmetric Rydberg excitation. This interaction enables a ground-state spin-flip blockade, whereby simultaneous hyperfine spin flips of two atoms are blockaded due to their mutual interaction. We employ this spin-flip blockade to rapidly produce single-step Bell-state entanglement between atoms. This work was supported by the Laboratory Directed Research and Development program at Sandia National Laboratories and through the National Science Foundation's Center for Quantum Information and Control NSF-1212445.

  15. A classical simulation of nonlinear Jaynes-Cummings and Rabi models in photonic lattices.

    PubMed

    Rodríguez-Lara, B M; Soto-Eguibar, Francisco; Cárdenas, Alejandro Zárate; Moya-Cessa, H M

    2013-05-20

    The interaction of a two-level atom with a single-mode quantized field is one of the simplest models in quantum optics. Under the rotating wave approximation, it is known as the Jaynes-Cummings model and without it as the Rabi model. Real-world realizations of the Jaynes-Cummings model include cavity, ion trap and circuit quantum electrodynamics. The Rabi model can be realized in circuit quantum electrodynamics. As soon as nonlinear couplings are introduced, feasible experimental realizations in quantum systems are drastically reduced. We propose a set of two photonic lattices that classically simulates the interaction of a single two-level system with a quantized field under field nonlinearities and nonlinear couplings as long as the quantum optics model conserves parity. We describe how to reconstruct the mean value of quantum optics measurements, such as photon number and atomic energy excitation, from the intensity and from the field, such as von Neumann entropy and fidelity, at the output of the photonic lattices. We discuss how typical initial states involving coherent or displaced Fock fields can be engineered from recently discussed Glauber-Fock lattices. As an example, the Buck-Sukumar model, where the coupling depends on the intensity of the field, is classically simulated for separable and entangled initial states. PMID:23736508

  16. Copper coordinated ligand thioether-S and NO2(-) oxidation: relevance to the CuM site of hydroxylases.

    PubMed

    Maji, Ram Chandra; Bhandari, Anirban; Singh, Ravindra; Roy, Suprakash; Chatterjee, Sudip K; Bowles, Faye L; Ghiassi, Kamran B; Maji, Milan; Olmstead, Marilyn M; Patra, Apurba K

    2015-10-28

    In order to gain insight into the coordination site and oxidative activity of the CuM site of hydroxylases such as peptidylglycine α-hydroxylating monooxygenase (PHM), dopamine β-monooxygenase (DβM), and tyramine β-monooxygenase (TβM), we have synthesized, characterized and studied the oxidation chemistry of copper complexes chelated by tridentate N2Sthioether, N2Osulfoxide or N2Osulfone donor sets. The ligands are those of N-2-methylthiophenyl-2'-pyridinecarboxamide (HL1), and the oxidized variants, N-2-methylsulfenatophenyl-2'-pyridinecarboxamide (HL1(SO)), and N-2-methylsulfinatophenyl-2'-pyridinecarboxamide (HL1(SO2)). Our studies afforded the complexes [(L1)Cu(II)(H2O)](ClO4)·H2O (1·H2O), {[(L1(SO))Cu(II)(CH3CN)](ClO4)}n (2), [(L1)Cu(II)(ONO)] (3), [(L1(SO))Cu(II)(ONO)]n (4), [(L1)Cu(II)(NO3)]n (5), [(L1(SO))Cu(II)(NO3)]n (6) and [(L1(SO2))Cu(II)(NO3)] (7). Complexes 1 and 3 were described in a previous publication (Inorg. Chem., 2013, 52, 11084). The X-ray crystal structures revealed either distorted octahedral (in 2, 4-6) or square-pyramidal (in 1, 3) coordination geometry around Cu(II) ions of the complexes. In the presence of H2O2, conversion of 1→2, 3-5→6 and 6→7 occurs quantitatively via oxidation of thioether-S and/or Cu(ii) coordinated NO2(-) ions. Thioether-S oxidation of L1 also occurs when [L1](-) is reacted with [Cu(I)(CH3CN)4](ClO4) in DMF under O2, albeit low in yield (20%). Oxidations of thioether-S and NO2(-) were monitored by UV-Vis spectroscopy. Recovery of the sulfur oxidized ligands from their metal complexes allowed for their characterization by elemental analysis, (1)H NMR, FTIR and mass spectrometry. PMID:26390838

  17. Geometric quantum discord of a Jaynes-Cummings atom and an isolated atom

    NASA Astrophysics Data System (ADS)

    Qiang, Wen-Chao; Zhang, Lei; Zhang, Hua-Ping

    2015-12-01

    We studied the geometric quantum discord of a quantum system consisting of a Jaynes-Cummings (JC) atom, a cavity and an isolated atom. The analytical expressions of the geometric quantum discord for two atoms, every atom with a cavity and the total system were obtained. We showed that the geometric quantum discord is not always zero when the entanglement falls to zero for a two-atom subsystem; the geometric measurement of the quantum discord of the total system developed periodically with a single frequency if the initial two-atom state was not entangled, otherwise, it oscillated with two or four frequencies according to whether the cavity was initially empty or not, respectively.

  18. Single-photon scattering in an optomechanical Jaynes-Cummings model

    NASA Astrophysics Data System (ADS)

    Ng, K. H.; Law, C. K.

    2016-04-01

    We investigate an optomechanical system which realizes the Jaynes-Cummings (JC) model known in cavity QED. Such a system consists of a single photon and an optomechanical cavity with two optical cavity modes and one mechanical mode. Under the resonance condition when the mechanical frequency is close to the frequency difference between the optical modes, the photon and phonons can be strongly coupled. We present an analytic solution of single-photon scattering and show that the spectrum of the scattered photon exhibits excitation-number-dependent Rabi splitting of the JC model. In addition, we examine the response of the mechanical mode to a sequence of single photons, with one photon in the cavity at a time. We show that sequential photon scattering can efficiently excite the mechanical mode and generate sub-Poisson phonon statistics.

  19. Vacuum-induced Berry phases in single-mode Jaynes-Cummings models

    NASA Astrophysics Data System (ADS)

    Liu, Yu; Wei, L. F.; Jia, W. Z.; Liang, J. Q.

    2010-10-01

    Motivated by work [Phys. Rev. Lett.PRLTAO0031-900710.1103/PhysRevLett.89.220404 89, 220404 (2002)] for detecting the vacuum-induced Berry phases with two-mode Jaynes-Cummings models (JCMs), we show here that, for a parameter-dependent single-mode JCM, certain atom-field states also acquired photon-number-dependent Berry phases after the parameter slowly changed and eventually returned to its initial value. This geometric effect related to the field quantization still exists, even if the field is kept in its vacuum state. Specifically, a feasible Ramsey interference experiment with a cavity quantum electrodynamics system is designed to detect the vacuum-induced Berry phase.

  20. Exact treatment of the Jaynes-Cummings model under the action of an external classical field

    NASA Astrophysics Data System (ADS)

    Abdalla, M. Sebawe; Khalil, E. M.; Obada, A. S.-F.

    2011-09-01

    We consider the usual Jaynes-Cummings model (JCM), in the presence of an external classical field. Under a certain canonical transformation for the Pauli operators, the system is transformed into the usual JCM. Using the equations of motion in the Heisenberg picture, exact solutions for the time-dependent dynamical operators are obtained. In order to calculate the expectation values of these operators, the wave function has been constructed. It has been shown that the classical field augments the atomic frequency ω0 and mixes the original atomic states. Changes of squeezing from one quadrature to another is also observed for a strong value of the coupling parameter of the classical field. Furthermore, the system in this case displays partial entanglement and the state of the field losses its purity.

  1. Photon spectra and statistics in generalized Jaynes-Cummings model with photon losses and atom motion

    NASA Astrophysics Data System (ADS)

    Gorokhov, A. V.; Sinaiski, I. E.

    2006-03-01

    The Jaynes-Cummings model (JCM) of two-level atom interacting with the photon mode in ideal cavity plays an essential role in modern quantum optics. In previous papers 1,2 an exact form of density matrix of the JCM with fixed atom position and photons dissipation was found. Here, taking into account the classical motion of the atom through the cavity, it is considered a case of nonideal cavity with zero temperature. We have obtained an exact expression for density matrix and calculated photon spectra and spectra of the mean number of photons in a cavity and and time dependencies of some values relevant for the one-atom maser theory.

  2. Green Synthesis of Silver Nanorods and Optimization of Its Therapeutic Cum Toxic Dose.

    PubMed

    Suganya, T R; Devasena, T

    2015-12-01

    Germinated Fenugreek seeds are relatively rich in flavonoids and polyphenols than dry seeds. Therefore, germinated fenugreek seeds possess better pharmacological activities. We have used an aqueous extract of germinated fenugreek seeds to reduce silver nitrate into nanoscale silver rods. The silver nanorods showed Surface Plasmon peak at 450 nm as revealed from UV visible spectrum. Field Emission Scanning Electron Microscopy images revealed the monodispersity and rod morphology. X ray diffraction spectrum revealed the FCC crystal structure of nanorods. Fourier transform infrared spectroscopy peaks revealed the interaction between the phytochemicals of germinated fenugreek seeds and the silver nanorods. Characterization studies reveal the validation of the proposed green synthesis protocol to produce monodispersed silver nanorods with phytochemical capping. The phytosynthesized silver nanorods exhibited anticancer activity in skin cancer cell line, which may be due to its nanoscale dimension and the surface functionalization. For the first time, we have optimized the therapeutic cum toxic dose of phytostabilized silver nanorods using skin cancer cell model. PMID:26682379

  3. Nonlinear Jaynes–Cummings model for two interacting two-level atoms

    NASA Astrophysics Data System (ADS)

    de los Santos-Sánchez, O.; González-Gutiérrez, C.; Récamier, J.

    2016-08-01

    In this work we examine a nonlinear version of the Jaynes–Cummings model for two identical two-level atoms allowing for Ising-like and dipole–dipole interplays between them. The model is said to be nonlinear in the sense that it can incorporate both a general intensity-dependent interaction between the atomic system and the cavity field and/or the presence of a nonlinear medium inside the cavity. As an example, we consider a particular type of atom-field coupling based upon the so-called Buck–Sukumar model and a lossless Kerr-like cavity. We describe the possible effects of such features on the evolution of some quantities of current interest, such as atomic excitation, purity, concurrence, the entropy of the field and the evolution of the latter in phase space.

  4. Equivalent spin-orbit interaction in the two-polariton Jaynes-Cummings-Hubbard model.

    PubMed

    Li, C; Zhang, X Z; Song, Z

    2015-01-01

    A cavity quantum electrodynamics (cavity-QED) system combines two or more distinct quantum components, exhibiting features not seen in the individual systems. In this work, we study the one-dimensional Jaynes-Cummings-Hubbard model in the two-excitation (two-polariton) subspace. We find that the centre momentum of two-excitation induces a magnetic flux piercing the equivalent Hamiltonian Hk in the invariant subspace with momentum k, which can be described as a 4-leg ladder in the auxiliary space. Furthermore, it is shown that the system in π-centre-momentum subspace is equivalent to a lattice system for spin-1 particle with spin-orbit coupling. On the basis of this concise description, a series of bound-pair eigenstates which display long-range polaritonic entanglement is presented as a simple application. PMID:26159665

  5. Non-equilibrium dynamics of a nonlinear Jaynes–Cummings model in cavity arrays

    NASA Astrophysics Data System (ADS)

    Minář, Jiří; Güneş Söyler, Şebnem; Lesanovsky, Igor

    2016-05-01

    We analyze in detail an open cavity array using mean-field description, where each cavity field is coupled to a number of three-level atoms. Such a system is highly tunable and can be described by a Jaynes–Cummings like Hamiltonian with additional nonlinear terms. In the single cavity case we provide simple analytic solutions and show, that the system features a bistable region. The extra nonlinear term gives rise to a rich dynamical behavior including occurrence of limit cycles through Hopf bifurcations. In the limit of large nonlinearity, the system exhibits an Ising like phase transition as the coupling between light and matter is varied. We then discuss how these results extend to the two-dimensional case.

  6. Management of open olecranon fractures using clamp-cum-compressor device

    PubMed Central

    Kundu, Zile Singh; Kamboj, P; Sangwan, SS; Siwach, RC; Singh, Raj; Walecha, P

    2009-01-01

    Background: Open fractures of olecranon are not a rare occurrence in patients with road traffic accidents particularly motor bike riders who don't use elbow guards. Definitive treatment has to be delayed in many till the wound heals. The present study was conducted to evaluate the results of open fractures of olecranon using clamp-cum-compressor device. Materials and Methods: Seventeen patients between the ages of 20 and 45 years of open olecranon fractures reported 5-20 days after injury were treated using an indigenous clamp-cum-compressor. All fractures were Mayo type II-A, i.e., displaced, stable and noncomminuted. Four patients had Gustilo-Anderson grade I and 13 had Gustilo-Anderson grade II open fractures. The patients with transverse or short oblique fractures were included in the study. The apparatus was applied under regional anesthesia after thorough washing and debridement of wounds with few loose sutures applied wherever needed. The wounds healed within 2-4 weeks and fractures united within 8-10 weeks. The elbow was mobilized with apparatus still in place. The results were evaluated by MayoElbow performance score. Results: We achieved excellent results in twelve patients, good in four and poor in one patient, who reported late, hooks of the apparatus were cut through the proximal fragment, leading to union of fracture in elongation and restricted elbow movements. Conclusion: The apparatus was found to be quite useful in transverse and short oblique fractures with contamination or infection, where internal fixation has to be delayed or avoided. PMID:19753180

  7. Prevalence and determinants of cannabinoid prescription for the management of chronic noncancer pain: a postal survey of physicians in the Abitibi-Témiscamingue region of Quebec

    PubMed Central

    St-Amant, Huguette; Ware, Mark A.; Julien, Nancy

    2015-01-01

    Background Few studies have been conducted to explore physicians’ prescription practices and attitudes toward the use of cannabinoids in Canada.We measured the prevalence and identified determinants of cannabinoid prescription for the management of chronic noncancer pain among physicians in southwestern Quebec. Methods In February 2013, we conducted a postal survey using a modified Dillman method that involved physicians practising in the Abitibi-Témiscamingue region of Quebec. We used multivariate logistic regression models to identify determinants of cannabinoid prescription. Results A total of 166 physicians of 318 practising in the region participated in the survey (response rate 52.2%). The prevalence of cannabinoid prescription was 27.3% (45/165) for any indication and 23.0% (38/165) for the management of chronic noncancer pain; 91.1% (41/45) of the physicians prescribed cannabinoids to 5 or fewer patients. Of the 38 physicians who prescribed cannabinoids for chronic noncancer pain, 35 (92.1%) prescribed nabilone, 7 (18.4%) medical marijuana and 2 (5.3%) nabiximols. The principal determinant of cannabinoid prescription was the physician’s level of comfort with prescribing cannabinoids (adjusted odds ratio 1.25, 95% confidence interval 1.01–1.55, per 1-point increase in comfort level measured on 10-point scale). Respondents reported that continuing medical education (CME) activities could increase their comfort level. They also indicated a need for guidelines or algorithms that included cannabinoid use as well as more studies about the efficacy and safety of cannabinoids for the management of chronic noncancer pain. Interpretation We found that cannabinoids were not often prescribed for the management of chronic noncancer pain and that survey respondents were not comfortable with prescribing this drug class. This degree of discomfort could be addressed by CME activities, more effective dissemination of guidelines and more evidence regarding cannabinoid

  8. Thermal analysis and neutron production characteristics of a low power copper beam dump-cum-target for LEHIPA

    NASA Astrophysics Data System (ADS)

    Sawant, Y. S.; Thomas, R. G.; Verma, V.; Agarwal, A.; Prasad, N. K.; Bhagwat, P. V.; Saxena, A.; Singh, P.

    2016-01-01

    Monte Carlo simulations of heat deposition and neutron production have been carried out for the low power beam dump-cum-target for the 20 MeV Low Energy High Intensity Proton Accelerator (LEHIPA) facility at BARC using GEANT4 and FLUKA. Thermal analysis and heat transfer calculations have also been carried out using the computational fluid dynamics code CFD ACE+. In this work we present the details of the analysis of the low power beam dump-cum-target designed for conditioning of the accelerator upto a maximum power of 600 kW with a duty cycle of 2% which corresponds to an average power of 12 kW in the first phase.

  9. The 1998 Donald E. Cummings Memorial Award Lecture. The industrial hygiene paradox, dilemmas, and a vision for the future.

    PubMed

    Lick, H B

    1998-11-01

    How do we move from diatribe to dialogue? Since the Donald E. Cummings Award was first established in 1943, the profession of industrial hygiene has seen many changes. The traditional hazards Alice Hamilton addressed in her 1948 Cummings lecture have been controlled. However, the advent of the Occupational Safety and Health Administration (OSHA) has changed the approach of many of today's industrial hygienists from "best professional practices" to regulatory compliance or OSHA industrial hygiene. Further, the dialogue that has existed between academia, business, government, and labor that allows industrial hygienists to identify and resolve health hazards is now threatened by lawsuits and lobbyists. Industrial hygienists have a professional responsibility to workers, employers, clients, and the public. Our vision for the future must refocus on this responsibility as we once again embrace dialogue instead of diatribe. This lecture was presented at the American Industrial Hygiene Conference and Exposition in Atlanta, Ga., on May 13, 1998. PMID:9830082

  10. Revival-collapse phenomenon in the quadrature squeezing of the multiphoton intensity-dependent Jaynes Cummings model

    NASA Astrophysics Data System (ADS)

    El-Orany, Faisal A. A.

    2006-12-01

    For the multiphoton intensity-dependent Jaynes Cummings model (JCM) described by a two-level atom interacting with a radiation field, we prove that there is a relationship between the atomic inversion and the quadrature squeezing. We give the required condition to obtain best information from this relation. Also we show that this relation is only sensitive to large values of the detuning parameter. Furthermore, we discuss briefly such relation for the off-resonance standard JCM.

  11. Linear entropies in the Jaynes Cummings model with intensity-dependent coupling in a phase-damped cavity

    NASA Astrophysics Data System (ADS)

    Zhou, Qing-Chun; Zhu, Shi-Ning

    2005-06-01

    We investigate the evolution of a quantum system described by the Jaynes-Cummings model with an arbitrary form of intensity-dependent coupling by displaying the linear entropies of the atom, field and atom-field system in the large detuning approximation. The cavity field is assumed to be coupled to a reservoir with a phase-damping coupling. The effects of cavity phase damping on the entanglement and coherence loss of such a system are studied.

  12. A note on approximate teleportation of an unknown atomic state in the two-photon Jaynes-Cummings model

    NASA Astrophysics Data System (ADS)

    dSouza, A. D.; Cardoso, W. B.; Avelar, A. T.; Baseia, B.

    2009-04-01

    We consider recent schemes [J.M. Liu, B. Weng, Physica A 367 (2006) 215] to teleport unknown atomic states and superposition of zero- and two-photon states using the two-photon Jaynes-Cummings model. Here we do the same using the “full two-photon Jaynes-Cumming”, valid for arbitrary average number of photons. The success probability and fidelity of this teleportation are also considered.

  13. Thermal-light-induced dynamics: Coherence and revivals in V -type and molecular Jaynes-Cummings systems

    NASA Astrophysics Data System (ADS)

    Avisar, David; Wilson-Gordon, A. D.

    2016-03-01

    We examine the interaction of thermal light with matter with emphasis on two aspects that have not been considered before. By employing a fully quantized Jaynes-Cummings-type interaction model on a V -type three-level system, we show that multimode thermal light induces coherence in the excited material states. This is in contrast to previous studies that suggest thermal light cannot induce coherence in material systems. We also show that the ratio between the field detuning and the interaction constant has a significant influence on the characteristic time-dependent dynamics. In particular, for some ratio regimes, the thermal light induces dynamics with a "coherentlike" collapse and revivals pattern rather than the familiar pattern. We then extend the Jaynes-Cummings model to a two-state Born-Oppenheimer potential energy surface molecular system where the internal vibrational degrees of freedom are fully taken into account. The matter-field bipartite system is represented, and propagated, in the full electronic bond-coordinate Fock product space. We show that single-mode thermal light induces extensive excited-state vibrational coherence in the molecule that, when observed in coordinate space, exhibits wave-packet-like dynamics. The molecular Jaynes-Cummings model we propose is useful for cavity molecular dynamics simulations.

  14. BreCAN-DB: a repository cum browser of personalized DNA breakpoint profiles of cancer genomes

    PubMed Central

    Narang, Pankaj; Dhapola, Parashar; Chowdhury, Shantanu

    2016-01-01

    BreCAN-DB (http://brecandb.igib.res.in) is a repository cum browser of whole genome somatic DNA breakpoint profiles of cancer genomes, mapped at single nucleotide resolution using deep sequencing data. These breakpoints are associated with deletions, insertions, inversions, tandem duplications, translocations and a combination of these structural genomic alterations. The current release of BreCAN-DB features breakpoint profiles from 99 cancer-normal pairs, comprising five cancer types. We identified DNA breakpoints across genomes using high-coverage next-generation sequencing data obtained from TCGA and dbGaP. Further, in these cancer genomes, we methodically identified breakpoint hotspots which were significantly enriched with somatic structural alterations. To visualize the breakpoint profiles, a next-generation genome browser was integrated with BreCAN-DB. Moreover, we also included previously reported breakpoint profiles from 138 cancer-normal pairs, spanning 10 cancer types into the browser. Additionally, BreCAN-DB allows one to identify breakpoint hotspots in user uploaded data set. We have also included a functionality to query overlap of any breakpoint profile with regions of user's interest. Users can download breakpoint profiles from the database or may submit their data to be integrated in BreCAN-DB. We believe that BreCAN-DB will be useful resource for genomics scientific community and is a step towards personalized cancer genomics. PMID:26586806

  15. Exact treatment of the Jaynes-Cummings model under the action of an external classical field

    SciTech Connect

    Abdalla, M. Sebawe; Khalil, E.M.; Obada, A.S.-F.

    2011-09-15

    We consider the usual Jaynes-Cummings model (JCM), in the presence of an external classical field. Under a certain canonical transformation for the Pauli operators, the system is transformed into the usual JCM. Using the equations of motion in the Heisenberg picture, exact solutions for the time-dependent dynamical operators are obtained. In order to calculate the expectation values of these operators, the wave function has been constructed. It has been shown that the classical field augments the atomic frequency {omega}{sub 0} and mixes the original atomic states. Changes of squeezing from one quadrature to another is also observed for a strong value of the coupling parameter of the classical field. Furthermore, the system in this case displays partial entanglement and the state of the field losses its purity. - Highlights: > The time-dependent JCM, in the presence of the classical field, is still one of the essential problems in the quantum optics. > A new approach is applied through a certain canonical transformation. > The classical field augments the atomic frequency {omega}{sub 0} and mixes the original atomic states.

  16. Dynamics of entanglement and quantum discord in the Tavis–Cummings model

    NASA Astrophysics Data System (ADS)

    Restrepo, Juliana; Rodríguez, Boris A.

    2016-06-01

    We revisit the problem of the dynamics of quantum correlations in the Tavis–Cummings model. Our results show that the dynamics of entanglement and quantum discord are far from being trivial or intuitive. We find states with the same entanglement but different discord and states where the two quantifiers give opposite information about correlations at a certain time. We furthermore show that many of the dynamical features of quantum discord attributed to dissipation are already present in the exact framework and are due to the characteristic quantum nonlinearity of the model and to the choice of initial conditions. Through a comprehensive analysis of pure and mixed initial conditions, we find a fascinating range of phenomena that can be used for experimental purposes. We propose an experiment called quantum discord gates where for a given pure initial condition discord is zero or non-zero depending on the number of photons in the cavity. Given the marginal character of states with zero discord this result is not only completely counterintuitive but is also useful as a way to count photons.

  17. Thermal Effects in Jaynes-Cummings Model Derived with Low-Temperature Expansion

    NASA Astrophysics Data System (ADS)

    Azuma, Hiroo; Ban, Masashi

    In this paper, we investigate thermal effects of the Jaynes-Cummings model (JCM) at finite temperature with a perturbative approach. We assume a single two-level atom and a single cavity mode to be initially in the thermal equilibrium state and the thermal coherent state, respectively, at a certain finite low temperature. Describing this system with Thermo Field Dynamics formalism, we obtain a low-temperature expansion of the atomic population inversion in a systematic manner. Letting the system evolve in time with the JCM Hamiltonian, we examine thermal effects of the collapse and the revival of the Rabi oscillations by means of the third-order perturbation theory under the low-temperature limit, that is to say, using the low-temperature expansion up to the third-order terms. From an intuitive discussion, we can expect that the period of the revival of the Rabi oscillations becomes longer as the temperature rises. Numerical results obtained with the perturbation theory reproduce well this temperature dependence of the period.

  18. Dynamics of entanglement and 'attractor' states in the Tavis-Cummings model

    NASA Astrophysics Data System (ADS)

    Jarvis, C. E. A.; Rodrigues, D. A.; Györffy, B. L.; Spiller, T. P.; Short, A. J.; Annett, J. F.

    2009-10-01

    We study the time evolution of Nq two-level atoms (or qubits) interacting with a single mode of a quantized radiation field. In the case of two qubits, we show that for a set of initial conditions the reduced density matrix of the atomic system approaches that of a pure state at {\\textstyle\\frac{t_{r}}{4}} , halfway between that start of the collapse and the first mini-revival peak, where tr is the time of the main revival. The pure state approached is the same for a set of initial conditions and is thus termed an 'attractor state'. The set itself is termed the 'basin of attraction' and we concentrate on its features. Extending to more qubits, we find that attractors are a generic feature of the multiqubit Jaynes-Cummings model (JCM) and we therefore generalize the discovery by Gea-Banacloche for the one-qubit case. We give the 'basin of attraction' for Nq qubits and discuss the implications of the 'attractor' state in terms of the dynamics of Nq-body entanglement. We observe both the collapse and revival and the sudden birth/death of entanglement depending on the initial conditions.

  19. Quasiperiodicity in time evolution of the Bloch vector under the thermal Jaynes-Cummings model

    NASA Astrophysics Data System (ADS)

    Azuma, Hiroo; Ban, Masashi

    2014-07-01

    We study a quasiperiodic structure in the time evolution of the Bloch vector, whose dynamics is governed by the thermal Jaynes-Cummings model (JCM). Putting the two-level atom into a certain pure state and the cavity field into a mixed state in thermal equilibrium at initial time, we let the whole system evolve according to the JCM Hamiltonian. During this time evolution, motion of the Bloch vector seems to be in disorder. Because of the thermal photon distribution, both a norm and a direction of the Bloch vector change hard at random. In this paper, taking a different viewpoint compared with ones that we have been used to, we investigate quasiperiodicity of the Bloch vector’s trajectories. Introducing the concept of the quasiperiodic motion, we can explain the confused behaviour of the system as an intermediate state between periodic and chaotic motions. More specifically, we discuss the following two facts: (1) If we adjust the time interval Δt properly, figures consisting of plotted dots at the constant time interval acquire scale invariance under replacement of Δt by sΔt, where s(>1) is an arbitrary real but not transcendental number. (2) We can compute values of the time variable t, which let |Sz(t)| (the absolute value of the z-component of the Bloch vector) be very small, with the Diophantine approximation (a rational approximation of an irrational number).

  20. A novel magnetic suspension cum linear actuator system for satellite cryo coolers

    SciTech Connect

    Sivadasan, K.K. . ISRO Inertial Systems Unit)

    1994-05-01

    Stirling cycle cryogenic coolers have been widely used for device cooling in satellites. Various types of magnetic bearings and linear actuators find application in such systems. The most widely used configurations have two-axis-radially-active suspension stations placed at either ends of a reciprocating shaft in the compression and expansion sections. Separate or integral liner motors are provided in each section for axial shaft movement. It may be noted that such configurations are rather complicated and less reliable because of the presence of numerous electro-mechanical components, sensors and electronic servo channels. In this paper, a simple and reliable scheme is suggested which axially stabilizes and linearly perturbs the piston so that the need for a separate motor for axial actuation can be totally dispensed with. The piston is radially supported by passive repulsive bearings. In the axial direction, a servo actuator balances'' the piston and also actuates it bi-directionally. Implemented of this bearing cum motor theme,'' reduces the number of electromechanical and electronic components required to operate the system and hence minimizes the chances of system failure. Apart from this, the system's power consumption is reduced and efficiency is improved as electrical heating losses caused by quiescent-operating currents are removed and electromagnetic losses on the moving parts are minimized. The necessary system parameters have been derived using finite element analysis techniques. Finally, the proposed design is validated by computer-aided system simulation.

  1. Design considerations for sludge fired fluidized bed incinerator-cum-boiler

    SciTech Connect

    Bapat, D.W.; Vishwanathan, K.

    1997-12-31

    Thermal Limited, a major player in the field of Fluidized Bed Boilers in India, has supplied on a turnkey basis, three boilers each of 22.5 tons per hour capacity as a part of Cogeneration system for PT. South Pacific Viscose, Indonesia. The plant generates huge volumes of sludge from its effluent Treatment Plant (ETP). The sludge produced from the ETP has a moisture content of about 98%, which is subsequently reduced to about 78% using a decanter before feeding the sludge into the boiler. The waste sludge has a negative heating value ({minus}150 kcal/kg on NCV basis) and required coal as support fuel for burning. The plant`s requirement was to incinerate the entire sludge generated in the plant, which meant that nearly 50% of the fuel fed to the boiler consisted of the waste sludge. Additional requirements were to burn coal and oil as back-up fuels. This paper deals with the challenges encountered and various design features provided in the configuration of the incinerator-cum-boiler including conveying, feeding and spreading arrangement of the waste sludge for effective incineration in addition to burning coal and oil. Also included in the paper is a brief description of the automatic control logics for combustion control and bed temperature control.

  2. BreCAN-DB: a repository cum browser of personalized DNA breakpoint profiles of cancer genomes.

    PubMed

    Narang, Pankaj; Dhapola, Parashar; Chowdhury, Shantanu

    2016-01-01

    BreCAN-DB (http://brecandb.igib.res.in) is a repository cum browser of whole genome somatic DNA breakpoint profiles of cancer genomes, mapped at single nucleotide resolution using deep sequencing data. These breakpoints are associated with deletions, insertions, inversions, tandem duplications, translocations and a combination of these structural genomic alterations. The current release of BreCAN-DB features breakpoint profiles from 99 cancer-normal pairs, comprising five cancer types. We identified DNA breakpoints across genomes using high-coverage next-generation sequencing data obtained from TCGA and dbGaP. Further, in these cancer genomes, we methodically identified breakpoint hotspots which were significantly enriched with somatic structural alterations. To visualize the breakpoint profiles, a next-generation genome browser was integrated with BreCAN-DB. Moreover, we also included previously reported breakpoint profiles from 138 cancer-normal pairs, spanning 10 cancer types into the browser. Additionally, BreCAN-DB allows one to identify breakpoint hotspots in user uploaded data set. We have also included a functionality to query overlap of any breakpoint profile with regions of user's interest. Users can download breakpoint profiles from the database or may submit their data to be integrated in BreCAN-DB. We believe that BreCAN-DB will be useful resource for genomics scientific community and is a step towards personalized cancer genomics. PMID:26586806

  3. Exploring the quantum critical behaviour in a driven Tavis-Cummings circuit.

    PubMed

    Feng, M; Zhong, Y P; Liu, T; Yan, L L; Yang, W L; Twamley, J; Wang, H

    2015-01-01

    Quantum phase transitions play an important role in many-body systems and have been a research focus in conventional condensed-matter physics over the past few decades. Artificial atoms, such as superconducting qubits that can be individually manipulated, provide a new paradigm of realising and exploring quantum phase transitions by engineering an on-chip quantum simulator. Here we demonstrate experimentally the quantum critical behaviour in a highly controllable superconducting circuit, consisting of four qubits coupled to a common resonator mode. By off-resonantly driving the system to renormalize the critical spin-field coupling strength, we have observed a four-qubit nonequilibrium quantum phase transition in a dynamical manner; that is, we sweep the critical coupling strength over time and monitor the four-qubit scaled moments for a signature of a structural change of the system's eigenstates. Our observation of the nonequilibrium quantum phase transition, which is in good agreement with the driven Tavis-Cummings theory under decoherence, offers new experimental approaches towards exploring quantum phase transition-related science, such as scaling behaviours, parity breaking and long-range quantum correlations. PMID:25971985

  4. Reentrant Behavior in A Multi-connected Superconducting Jaynes-Cummings Lattice

    NASA Astrophysics Data System (ADS)

    Tian, Lin; Seo, Kangjun

    2015-03-01

    Superconducting quantum devices have excellent connectivity, tunable coupling and long decoherence time as demonstrated by recent experiments. These devices provide a powerful platform for constructing analog quantum simulators to study novel many-body effects. Here we present a multi-connected Jaynes-Cummings lattice model, where the qubits and the resonators are connected alternatively. In a one-dimensional configuration, this model bears an intrinsic symmetry between the left and the right qubit-resonator couplings under a mirror reflection. Different from the coupled cavity array (CCA) model, the qubit-resonator couplings in this model induce both onsite Hubbard nonlinearity and hopping of the excitations along the lattice. By analyzing this model in the limiting cases of very different couplings, we show that this model demonstrates a Mott insulator-superfluid-Mott insulator transition at commensurate fillings with symmetric critical points. The reentry to the Mott insulator phase originates from the symmetry between the couplings. This work is supported by the NSF Award 0956064.

  5. Entanglement dynamics of two independent Jaynes-Cummings atoms without the rotating-wave approximation

    SciTech Connect

    Chen Qinghu; Yang Yuan; Liu Tao; Wang Kelin

    2010-11-15

    Entanglement evolution of two independent Jaynes-Cummings atoms without the rotating-wave approximation (RWA) is studied by a numerically exact approach. Previous results based on the RWA are essentially modified in the strong-coupling regime (g{>=}0.1), which has been reached in the recent experiments on the flux qubit coupled to the LC resonator. For the initial Bell state with anticorrelated spins, entanglement sudden death (ESD) is absent in the RWA but does appear in the present numerical calculation without the RWA. Aperiodic entanglement evolution in the strong-coupling regime is observed. The strong atom-cavity coupling facilitates the ESD. The sign of the detuning plays an essential role in the entanglement evolution for strong coupling, which is irrelevant in the RWA. Analytical results based on an unitary transformation are also given, which could not modify the RWA picture essentially. It is suggested that the activation of the photons may be the origin of ESD in this system.

  6. Trojan Wave Packets in the Quantum Cavity within the Extended Jaynes-Cummings Model

    NASA Astrophysics Data System (ADS)

    Kalinski, Matt

    2016-05-01

    Some time ago we have developed the theory of the Trojan Wave Packets (TWP) in the classical strong Circularly Polarized electromagnetic field in terms of the Mathieu generating functions. We have discovered that by the proper partitioning of the Coulomb spectrum i.e. by considering the deviation from the circularity and the vertical tilt of the undressed states as the new quantum numbers we can reduce the problem to the problem of several non-interacting quantum pendula for the Stark-Zeeman field dressed states. The TWP in the infinite physical space however turned out to be weakly unstable due to the spontaneous emission. Here we develop the theory in which the TWP is truly eternal when the electromagnetic interactions are considered quantum and the field is confined by the perfect quantum cavity boundary conditions. First we extend the Jaynes-Cummings (JC) model from the two to the infinite number of levels interacting with the one or two perfectly resonant quantum modes of the electromagnetic field. Similarly the model of JC and our previous pendular model the dressed electron-field eigenstates are constructed within the weakly interacting manifolds. Superpositions of those states are possible with the quantum electron density moving on the circular trajectories.

  7. Exploring the quantum critical behaviour in a driven Tavis–Cummings circuit

    PubMed Central

    Feng, M.; Zhong, Y.P.; Liu, T.; Yan, L.L.; Yang, W.L.; Twamley, J.; Wang, H.

    2015-01-01

    Quantum phase transitions play an important role in many-body systems and have been a research focus in conventional condensed-matter physics over the past few decades. Artificial atoms, such as superconducting qubits that can be individually manipulated, provide a new paradigm of realising and exploring quantum phase transitions by engineering an on-chip quantum simulator. Here we demonstrate experimentally the quantum critical behaviour in a highly controllable superconducting circuit, consisting of four qubits coupled to a common resonator mode. By off-resonantly driving the system to renormalize the critical spin-field coupling strength, we have observed a four-qubit nonequilibrium quantum phase transition in a dynamical manner; that is, we sweep the critical coupling strength over time and monitor the four-qubit scaled moments for a signature of a structural change of the system's eigenstates. Our observation of the nonequilibrium quantum phase transition, which is in good agreement with the driven Tavis–Cummings theory under decoherence, offers new experimental approaches towards exploring quantum phase transition-related science, such as scaling behaviours, parity breaking and long-range quantum correlations. PMID:25971985

  8. Design, development and performance evaluation of chapati press cum vermicelli extruder.

    PubMed

    Gurushree, M N; Nandini, C R; Pratheeksha, K; Prabhasankar, P; Hosamane, Gangadharappa Gundabhakthara

    2011-04-01

    Portable and manually operated chapati press cum vermicelli extruder device was designed and fabricated for the preparation of chapatis and vermicelli. Sensory evaluation overall quality scores of 50.15 and 48.4 for pressed chapatis and rolled chapatis respectively showed that quality of chapatis was not adversely affected as a result of mechanical pressing. The difference in chapati making time by manual rolling and machine pressing was 17 s per chapati and was statistically significant (p < 0.05). Combined machine produced more numbers of chapatis as machine press time per chapati was 12 s compared to 29 s of manual sheeting time. The observed variation in 1.5 mm thickness and 173.8 mm diameter from chapati to chapati was of the order of ± 0.1 mm and 1.93 mm respectively. Pressed chapati repeatability results indicated that there was no significant difference in diameters of the samples. Appearance quality characteristics scores of 8 and 7 for 2 mm and 3 mm diameter vermicelli respectively indicated smooth and uniform surface characteristics. Sensory evaluation of the cooked vermicelli indicated no significant difference (p > 0.05) between 2 mm and 3 mm diameter vermicelli. Cooked weight (72.8 g) and water absorption (191.2%) of 2 mm diameter vermicelli was more compared to 3 mm diameter vermicelli (51.75 g, 107%). This machine can also be used as a laboratory model as products of consistent thickness and diameter were obtained. PMID:23572737

  9. Covalent cum noncovalent functionalizations of carbon nanotubes for effective reinforcement of a solution cast composite film.

    PubMed

    Yuan, Wei; Chan-Park, Mary B

    2012-04-01

    Although carbon nanotubes have impressive tensile properties, exploiting these properties in composites, especially those made by the common solution casting technique, seems to be elusive thus far. The reasons could be partly due to the poor nanotube dispersion and the weak nanotube/matrix interface. To solve this dual pronged problem, we combine noncovalent and covalent functionalizations of nanotubes in a single system by the design and application of a novel dispersant, hydroxyl polyimide-graft-bisphenol A diglyceryl acrylate (PI(OH)-BDA), and use them with epoxidized single-walled carbon nanotubes (O-SWNTs). Our novel PI(OH)-BDA dispersant functionalizes the nanotubes noncovalently to achieve good dispersion of the nanotubes because of the strong π-π interaction due to main chain and steric hindrance of the BDA side chain. PI(OH)-BDA also functionalizes O-SWNTs covalently because it reacts with epoxide groups on the nanotubes, as well as the cyanate ester (CE) matrix used. The resulting solution-cast CE composites show 57%, 71%, and 124% increases in Young's modulus, tensile strength, and toughness over neat CE. These values are higher than those of composites reinforced with pristine SWNTs, epoxidized SWNTs, and pristine SWNTs dispersed with PI(OH)-BDA. The modulus and strength increase per unit nanotube weight fraction, i.e., dE/dW(NT) and dσ/dW(NT), are 175 GPa and 7220 MPa, respectively, which are significantly higher than those of other nanotube/thermosetting composites (22-70 GPa and 140-3540 MPa, respectively). Our study indicates that covalent cum noncovalent functionalization of nanotubes is an effective tool for improving both the nanotube dispersion and nanotube/matrix interfacial interaction, resulting in significantly improved mechanical reinforcement of the solution-cast composites. PMID:22432973

  10. Fluid chemistry and evolution of hydrothermal fluids in an Archaean transcrustal fault zone network: The case of the Cadillac Tectonic Zone, Abitibi greenstone belt, Canada

    USGS Publications Warehouse

    Neumayr, P.; Hagemann, S.G.; Banks, D.A.; Yardley, B.W.D.; Couture, J.-F.; Landis, G.P.; Rye, R.

    2007-01-01

    Detailed fluid geochemistry studies on hydrothermal quartz veins from the Rouyn-Noranda and Val-d'Or areas along the transcrustal Cadillac Tectonic Zone (CTZ) indicate that unmineralized (with respect to gold) sections of the CTZ contained a distinct CO2-dominated, H2S-poor hydrothermal fluid. In contrast, both gold mineralized sections of the CTZ (e.g., at Orenada #2) and associated higher order shear zones have a H2O-CO2 ?? CH4-NaCl hydrothermal fluid. Their CO2/H2S ratios indicate H2S-rich compositions. The Br/Cl compositions in fluid inclusions trapped in these veins indicate that hydrothermal fluids have been equilibrated with the crust. Oxygen isotope ratios from hydrothermal quartz veins in the CTZ are consistently 2??? more enriched than those of associated higher order shear zones, which are interpreted to be a function of greater fluid/rock ratios in the CTZ and lower fluid/rock ratios, and more efficient equilibration of the hydrothermal fluid with the wall rock, in higher order shear zones. An implication from this study is that the lower metal endowment of the transcrustal CTZ, when compared with the higher metal endowment in higher order shear zones (ratio of about 1 : 1000), may be the result of the lack of significant amounts of H2O-H2S rich fluids in most of the CTZ. In contrast, gold mineralization in the higher order shear zones appear to be controlled by the high H2S activity of the aqueous fluids, because gold was likely transported in a bisulfide complex and was deposited during sulfidation reactions in the wall rock and phase separation in the quartz veins. ?? 2007 NRC Canada.

  11. Exact mapping of the 2+1 Dirac oscillator onto the Jaynes-Cummings model: Ion-trap experimental proposal

    SciTech Connect

    Bermudez, A.; Martin-Delgado, M. A.; Solano, E.

    2007-10-15

    We study the dynamics of the 2+1 Dirac oscillator exactly and find spin oscillations due to a Zitterbewegung of purely relativistic origin. We find an exact mapping of this quantum-relativistic system onto a Jaynes-Cummings model, describing the interaction of a two-level atom with a quantized single-mode field. This equivalence allows us to map a series of quantum optical phenomena onto the relativistic oscillator and vice versa. We make a realistic experimental proposal, in reach with current technology, for studying the equivalence of both models using a single trapped ion.

  12. Protracted tectono-metamorphic history of the SE Superior Province : contribution of 40Ar/39Ar thermochronology in the Abitibi-Opatica contact zone, Québec, Canada

    NASA Astrophysics Data System (ADS)

    Daoudene, Yannick; Tremblay, Alain; Ruffet, Gilles; Leclerc, François; Goutier, Jean

    2015-04-01

    Archean orogens mainly consist of greenstone belts juxtaposing deeper crustal domains of TTG-type plutonic rocks. The greenstone belts show regional folds, penetrative steeply-dipping fabrics, and localised shear zones, whereas the plutonic belts predominantly display dome structures. Concurrently, rocks in Archean orogens undergone MT/HT-LP/MP metamorphic conditions that vary, from upper to lower crustal domains, between greenschist- and granulite-facies, respectively. These structural and metamorphic variations are well-documented, but modes of deformation related to such orogens is still debated. Some studies suggest that the Archean tectonic processes were comparable to present-day plate tectonics and the Archean greenstone belts were interpreted as tectonic collages commonly documented in Phanerozoic subduction/collision zones. Alternative models propose that the Archean tectonics were different from those predicted by the plate tectonics paradigm, mainly due to the existence of a hotter mantle and a mechanically weak crust. In such models, the burying and exhumation of crustal rocks are attributed to the vertical transfer of material, resulting in the development of pop-down and domes structures. As a contribution of the study of mechanisms that might have operated during the Archean, we present a structural and metamorphic study of the contact zone between the Abitibi subprovince (ASP), which contains greenstone belts, and the Opatica subprovince (OSP), which is dominated by plutonic rocks, of the Superior Province. The 40Ar/39Ar dating of amphiboles and micas is used to constrain the age and duration of regional metamorphism and associated deformations. On the basis of seismic profiling, showing a north-dipping lithospheric-scale reflector, the ASP-OSP contact has been interpreted as the surficial trace of an Archean subduction zone. However, our structural analysis suggest that the ASP overlies the OSP and that the ASP-OSP contact does not show evidences

  13. Conceptual Change cum Discourse Analysis to Understand Cognition in a Unit on Chaotic Systems: Towards an Integrative Perspective on Learning in Science.

    ERIC Educational Resources Information Center

    Duit, Reinders; Roth, Wolff-Michael; Komorek, Michael; Wilbers, Jens

    1998-01-01

    Illustrates how a well-designed curriculum can lead students to construct an unwanted conception. Concludes that the conceptual-change-cum-discourse perspective has the potential to integrate the affordances of both methodological approaches and past empirical accomplishments. Contains 33 references. (DDR)

  14. Exact time-dependent pointer state in a Jaynes-Cummings model with intensity-dependent level shift

    NASA Astrophysics Data System (ADS)

    Zhang, Xin; Xu, Chang; Ren, Zhongzhou

    2015-06-01

    We show that in the Jaynes-Cummings model with an intensity-dependent level shift whose magnitude is tuned to give rise to periodic collapse and revival, there exists a kind of time evolution where the two-level system and a coherent boson field stay absolutely disentangled throughout the evolution, in spite of the nonzero interaction between them. This constitutes an explicit example for an exact time-dependent pointer state of the two-level system, which perhaps distinguishes this evolution from all known disentangled evolutions in JC-related models. The construction of such an evolution is made possible by a vast level degeneracy in the energy level structure. Two possible ways to observe this phenomenon are also discussed. We believe that the present work could contribute to the understanding of pointer states.

  15. Note: Compact, reusable inductive-storage-cum-opening-switch based 1.5 GW single-shot pulsed power generator

    NASA Astrophysics Data System (ADS)

    Shukla, Rohit; Shyam, Anurag

    2014-03-01

    The results of a very-compact (Marx generator-cum-inductor confined into 0.20 m cylindrical diameter and 0.75 m length) and light-weight (<15 kg) pulsed-power generator are being presented in the paper. The load voltage at 10.5 Ω is measured 125 kV (150 ns full width at half maximum FWHM) with 1.5 GW peak-power. The use of single-optimized-exploding-copper-wire along with the use of air for all the switches of the generator (closing switches of Marx generator used as primary energy source and opening switch of exploding wire) make device very attractive. Marx generator shape itself provides the desired inductance for the inductive storage.

  16. Note: Compact, reusable inductive-storage-cum-opening-switch based 1.5 GW single-shot pulsed power generator.

    PubMed

    Shukla, Rohit; Shyam, Anurag

    2014-03-01

    The results of a very-compact (Marx generator-cum-inductor confined into 0.20 m cylindrical diameter and 0.75 m length) and light-weight (<15 kg) pulsed-power generator are being presented in the paper. The load voltage at 10.5 Ω is measured 125 kV (150 ns full width at half maximum FWHM) with 1.5 GW peak-power. The use of single-optimized-exploding-copper-wire along with the use of air for all the switches of the generator (closing switches of Marx generator used as primary energy source and opening switch of exploding wire) make device very attractive. Marx generator shape itself provides the desired inductance for the inductive storage. PMID:24689629

  17. Evolution of the superposition of displaced number states with the two-atom multiphoton Jaynes Cummings model: interference and entanglement

    NASA Astrophysics Data System (ADS)

    El-Orany, Faisal A. A.

    2006-11-01

    In this paper, we study the evolution of two two-level atoms interacting with a single-mode quantized radiation field, namely, the two-atom multiphoton Jaynes-Cummings model (JCM). We assume that the field and the atoms are initially prepared in the superposition of displaced number states and excited atomic states, respectively. For this system, we investigate the atomic inversion, Wigner function, phase distribution and entanglement. We show that for symmetric (asymmetric) atoms, the system can generate asymmetric (symmetric) cat states at a quarter of the revival time. Furthermore, the degrees of entanglement for the field-atoms and the one-atom-remainder tangles depend on the rate of energy flow between the parties. The interference in phase space decreases the degree of entanglement in the bipartite.

  18. Interaction of a Two-Level Atom with the Morse Potential in the Framework of Jaynes-Cummings Model

    NASA Astrophysics Data System (ADS)

    Setare R., M.; Sh., Barzanjeh

    2009-09-01

    A theoretical study of the dynamical behaviors of the interaction between a two-level atom with a Morse potential in the framework of the Jaynes-Cummings model (JCM) is discussed. We show that this system is equivalent to an intensity-dependent coupling between the two-level atom and the non-deformed single-mode radiation field in the presence of an additional nonlinear interaction. We study the dynamical properties of the system such as, atomic population inversion, the probability distribution of cavity-field, the Mandel parameter and atomic dipole squeezing. It is shown how the depth of the Morse potential can be affected by non-classical properties of the system. Moreover, the temporal evolution of the Husimi-distribution function is explored.

  19. Phase Distribution of the Output of Jaynes-Cummings Model with the Superposition of Squeezed Displaced Fock States

    NASA Astrophysics Data System (ADS)

    Abd Al-Kader, G. M.

    2006-05-01

    The Wigner quasi-probability function for the superposition of squeezed displaced Fock states (SDFS's) is reviewed. The interaction of these states with a two-level atom in cavity with the presence of additional Kerr medium is studied. Exact general matrix elements of the time-dependent operators of a Jaynes-Cummings model (JCM), in the presence of a Kerr medium, with these states are derived. We have obtained the phase distribution by two different ways: one is by Pegg-Barnett formalism, the second is by integration of the Wigner function over the radial variable. Results of these two approaches are compared. The Wigner phase distributions for some values of parameters are illustrated. The behaviors of the distributions have been shown as a function of the squeeze parameter in JCM.

  20. Equivalence of a compressible inviscid flow and the Bloch vector under the thermal Jaynes-Cummings model

    NASA Astrophysics Data System (ADS)

    Azuma, Hiroo; Ban, Masashi

    2015-07-01

    In this paper, we show that the time evolution of the Bloch vector governed by the thermal Jaynes-Cummings model is equivalent to a compressible inviscid flow with zero vorticity. Because of its quasiperiodicity, the dynamics of the Bloch vector includes countably infinite angular momenta as integrals of motion. Moreover, to derive the Bloch vector, we trace out the Hilbert space of the cavity field and remove entanglement between the single atom and the cavity mode. These facts indicate that the dynamics of the Bloch vector can be described with a hidden-variable model that has local determinism and a countably infinite number of degrees of freedom. Our results fit these considerations.

  1. On the relationship between the classical Dicke-Jaynes-Cummings-Gaudin model and the nonlinear Schroedinger equation

    SciTech Connect

    Du, Dianlou; Geng, Xue

    2013-05-15

    In this paper, the relationship between the classical Dicke-Jaynes-Cummings-Gaudin (DJCG) model and the nonlinear Schroedinger (NLS) equation is studied. It is shown that the classical DJCG model is equivalent to a stationary NLS equation. Moreover, the standard NLS equation can be solved by the classical DJCG model and a suitably chosen higher order flow. Further, it is also shown that classical DJCG model can be transformed into the classical Gaudin spin model in an external magnetic field through a deformation of Lax matrix. Finally, the separated variables are constructed on the common level sets of Casimir functions and the generalized action-angle coordinates are introduced via the Hamilton-Jacobi equation.

  2. Dynamics of Information Entropies of Atom-Field Entangled States Generated via the Jaynes–Cummings Model

    NASA Astrophysics Data System (ADS)

    Pakniat, R.; Tavassoly, M. K.; Zandi, M. H.

    2016-03-01

    In this paper we have studied the dynamical evolution of Shannon information entropies in position and momentum spaces for two classes of (nonstationary) atom-field entangled states, which are obtained via the Jaynes–Cummings model and its generalization. We have focused on the interaction between two- and Ξ-type three-level atoms with the single-mode quantized field. The three-dimensional plots of entropy densities in position and momentum spaces are presented versus corresponding coordinates and time, numerically. It is observed that for particular values of the parameters of the systems, the entropy squeezing in position space occurs. Finally, we have shown that the well-known BBM (Beckner, Bialynicki-Birola and Mycielsky) inequality, which is a stronger statement of the Heisenberg uncertainty relation, is properly satisfied.

  3. Influence of Stark Shift on Entanglement of Two Qubits in the Two-Photon Tavis-Cummings Model

    NASA Astrophysics Data System (ADS)

    Mastyugin, M. S.; Bashkirov, E. K.

    2015-09-01

    Considering two-atom degenerate two-photon Tavis-Cummings model, we investigate the entanglement between two atoms prepared initially in the coherent disentangled states and cavity field prepared in few-photon Fock state, and study the effect of the Stark shift on entanglement. The results show that the atom-atom negativity evolve periodically with time and the periods are affected by the Stark shift and initial coherent atomic state and that the atom-atom entanglement can be greatly enhanced due to the presence of Stark shift. We also have shown that entanglement sudden death effect vanishes for some parameters of the considered system due to the presence of Stark shift. In addition, the entanglement sudden death effect vanishes due to the presence of Stark shift. We have derived that the dynamic Stark shift can be used to control entanglement between two initially disentangled atoms.

  4. General integrable n-level, many-mode Janes-Cummings-Dicke models and classical r-matrices with spectral parameters

    SciTech Connect

    Skrypnyk, T. E-mail: tskrypnyk@imath.kiev.ua

    2015-02-15

    Using the technique of classical r-matrices and quantum Lax operators, we construct the most general form of the quantum integrable “n-level, many-mode” spin-boson Jaynes-Cummings-Dicke-type hamiltonians describing an interaction of a molecule of N n-level atoms with many modes of electromagnetic field and containing, in general, additional non-linear interaction terms. We explicitly obtain the corresponding quantum Lax operators and spin-boson analogs of the generalized Gaudin hamiltonians and prove their quantum commutativity. We investigate symmetries of the obtained models that are associated with the geometric symmetries of the classical r-matrices and construct the corresponding algebra of quantum integrals. We consider in detail three classes of non-skew-symmetric classical r-matrices with spectral parameters and explicitly obtain the corresponding quantum Lax operators and Jaynes-Cummings-Dicke-type hamiltonians depending on the considered r-matrix.

  5. Influence of the Kerr effect in a Mott insulator on the superfluid transition from the point of view of the Jaynes-Cummings-Hubbard model

    NASA Astrophysics Data System (ADS)

    Gomes, Clélio B. C.; Almeida, Francisco A. G.; Souza, Andre M. C.

    2016-04-01

    We have studied analytically the Jaynes-Cummings-Hubbard model for a one-dimensional optical lattice with the account of the Kerr-type nonlinearity under the fermionic approximation. We have found that an increase in the number of photons or in the detuning parameter favors the superfluid phase. We have also found that the nonlinear Kerr effect favors the Mott insulator phase, which is in agreement with experimental observations.

  6. A transparent mechanism of Q function splitting in a Jaynes-Cummings model with intensity-dependent level shift

    NASA Astrophysics Data System (ADS)

    Zhang, Xin; Xu, Chang; Ren, Zhongzhou

    2015-10-01

    We investigate the tripartite relationship between the collapse and revival, the Q function splitting and the energy level structure in the Jaynes-Cummings (JC) model with an intensity-dependent level shift whose magnitude is tuned to give rise to periodic collapse and revivals. We show that this constitutes a clearer demonstration of the mechanism of Q function splitting and its relation with the collapse and revival than the standard JC model itself. The eigenstates form two groups, both of which form equidistant ladders with differing energy intervals. This structure gives rise to the periodic splitting and reunion of the Q function. Only when the reunion happens, a non-vanishing mutual interference between the two groups is possible and gives rise to observable Rabi oscillations. The possibility of observing the phenomena using a Rubidium atom in a cavity is also discussed. We believe the present work could contribute to the understanding of the collapse and revival and the Q function-splitting phenomena.

  7. Application of Abel-Plana Formula for Collapse and Revival of Rabi Oscillations in Jaynes-Cummings Model

    NASA Astrophysics Data System (ADS)

    Azuma, Hiroo

    In this paper, we give an analytical treatment to study the behavior of the collapse and the revival of the Rabi oscillations in the Jaynes-Cummings model (JCM). The JCM is an exactly soluble quantum mechanical model, which describes the interaction between a two-level atom and a single cavity mode of the electromagnetic field. If we prepare the atom in the ground state and the cavity mode in a coherent state initially, the JCM causes the collapse and the revival of the Rabi oscillations many times in a complicated pattern in its time-evolution. In this phenomenon, the atomic population inversion is described with an intractable infinite series. (When the electromagnetic field is resonant with the atom, the nth term of this infinite series is given by a trigonometric function for √ {n} t, where t is a variable of the time.) According to Klimov and Chumakov's method, using the Abel-Plana formula, we rewrite this infinite series as a sum of two integrals. We examine the physical meanings of these two integrals and find that the first one represents the initial collapse (the semi-classical limit) and the second one represents the revival (the quantum correction) in the JCM. Furthermore, we evaluate the first- and second-order perturbations for the time-evolution of the JCM with an initial thermal coherent state for the cavity mode at low temperature, and write down their correction terms as sums of integrals by making use of the Abel-Plana formula.

  8. The revival collapse phenomenon in the quadrature field components of the two-mode multiphoton Jaynes Cummings model

    NASA Astrophysics Data System (ADS)

    El-Orany, Faisal A. A.

    2005-11-01

    In this paper we consider a system consisting of a two-level atom in an excited state interacting with two modes of a radiation field prepared initially in l-photon coherent states. This system is described by a two-mode multiphoton (i.e., k1,k2) Jaynes-Cummings model (JCM). For this system we investigate the occurrence of the revival-collapse phenomenon (RCP) in the evolution of the single-mode, two-mode, sum and difference quadrature squeezing. We show that there is a class of states for which all these types of squeezing exhibit RCP similar to that involved in the corresponding atomic inversion. Also we show numerically that the single-mode squeezing of the first mode for (k1,k2) = (3,1) provides RCP similar to that of the atomic inversion of the case (k1,k2) = (1,1); however, sum and difference squeezing give partial information on that case. Moreover, we show that single-mode, two-mode and sum squeezing for the case (k1,k2) = (2,2) provides information on the atomic inversion of the single-mode two-photon JCM. We derive the rescaled squeezing factors giving accurate information on the atomic inversion for all cases. The consequences of these results are that the homodyne and heterodyne detectors can be used to detect the RCP for the two-mode JCM.

  9. Source identification of different size fraction of PM10 using factor analysis at residential cum commercial area of Nagpur city.

    PubMed

    Pipalatkar, P P; Gajghate, D G; Khaparde, V V

    2012-02-01

    Particulate size distribution of PM(10) and associated trace metal concentrations has been carried out in residential cum commercial area of Mahal at Nagpur city. Sampling for size fraction of particulate matter was performed during winter season using eight-stage cascade impactor with a pre-separator and toxic metals were analyzed using inductively coupled plasma-optical emission spectroscopy (ICP-OES). The average concentration of PM(10) and fine particulate matter (effective cut of aerodynamic diameter ≤2.2 μm) was found to be 300 and 136.7 μg/m(3), respectively which was exceeding limit of Central Pollution Control Board. Maximum mass concentration of 41 μg/m(3) in size range of 9.0-10.0 μm and minimum mass concentration of 19 μg/m(3) in size range 2.2-3.3 μm was observed. Metals (Sr, Ni and Zn) were found to large proportions in below 0.7 μm particle size and could therefore pass directly into the alveoli region of human respiratory system. Factor analysis results indicated combustion and vehicular emission as the dominant source in fine mode and resuspended dust was dominant in medium mode while crustal along with vehicular source was major in coarse mode of particulate matter. PMID:22033656

  10. a Class of Regression-Cum Estimators in Two-Phase Sampling for Utilizing Information from High Resolution Satellite Data

    NASA Astrophysics Data System (ADS)

    Handique, B. K.

    2012-07-01

    Two-phase sampling design offers a variety of possibilities for effective use of auxiliary information such as those from high resolution remote sensing data. Continuous satellite data with large area coverage provide scope for deriving population values of the auxiliary variables, which can effectively be used for estimating the population parameters of the variable of interest. This study has been made to examine the possibilities of different forms of auxiliary information derived from remote sensing data in two-phase sampling design and suggest an appropriate estimator that will be of broad interest and applications. A new class of regression-cum-ratio estimators has been proposed for two-phase sampling using information on two auxiliary variables derived from high resolution satellite data. The bias and the mean square error (MSE) of the proposed estimators have been obtained up to first order approximation. Efficiency comparison of the proposed estimators has been made with some traditional estimators. The proposed estimator is found to be more efficient than the usual regression and ratio estimators. Numerical illustration has been carried out to examine the efficiency of the estimator in case of forest timber volume estimation utilizing tree crown diameter and tree height as auxiliary variables. It is shown that these estimators can be employed in a variety of conditions where there is strong correlation of satellite derived information with sample based ground measurements and when the cost of ground measurements is relatively high.

  11. What can we learn from the dynamics of entanglement and quantum discord in the Tavis-Cummings model?

    NASA Astrophysics Data System (ADS)

    Restrepo, Juliana; Rodriguez, Boris A.

    We revisit the problem of the dynamics of quantum correlations in the exact Tavis-Cummings model. We show that many of the dynamical features of quantum discord attributed to dissipation are already present in the exact framework and are due to the well known non-linearities in the model and to the choice of initial conditions. Through a comprehensive analysis, supported by explicit analytical calculations, we find that the dynamics of entanglement and quantum discord are far from being trivial or intuitive. In this context, we find states that are indistinguishable from the point of view of entanglement and distinguishable from the point of view of quantum discord, states where the two quantifiers give opposite information and states where they give roughly the same information about correlations at a certain time. Depending on the initial conditions, this model exhibits a fascinating range of phenomena that can be used for experimental purposes such as: Robust states against change of manifold or dissipation, tunable entanglement states and states with a counterintuitive sudden birth as the number of photons increase. We furthermore propose an experiment called quantum discord gates where discord is zero or non-zero depending on the number of photons. This work was supported by the Vicerrectoria de Investigacion of the Universidad Antonio Narino, Colombia under Project Number 20141031 and by the Departamento Administrativo de Ciencia, Tecnologia e Innovacion (COLCIENCIAS) of Colombia under Grant Number.

  12. Side-on cupric-superoxo triplet complexes as competent agents for H-abstraction relevant to the active site of PHM.

    PubMed

    Sánchez-Eguía, B N; Flores-Alamo, M; Orio, M; Castillo, I

    2015-07-14

    Copper complexes with N3S donors mimic the CuM site of copper monooxygenases and react with O2 affording side-on cupric-superoxo complexes capable of H-abstraction from dihydroanthracene and THF. Spectroscopic and DFT data of the Cu-superoxos support a spin triplet ground state for the side-on complexes, as well as a hemilabile thioether. PMID:26073167

  13. Entanglement, quantum phase transition and fixed-point bifurcation in the N-atom Jaynes Cummings model with an additional symmetry breaking term

    NASA Astrophysics Data System (ADS)

    Chagas, E. A.; Furuya, K.

    2008-08-01

    In the present work we analyze the quantum phase transition (QPT) in the N-atom Jaynes-Cummings model (NJCM) with an additional symmetry breaking interaction term in the Hamiltonian. We show that depending on the type of symmetry breaking term added the transition order can change or not and also the fixed point associated to the classical analogue of the Hamiltonian can bifurcate or not. We present two examples of symmetry broken Hamiltonians and discuss based on them, the interconnection between the transition order, appearance of bifurcation and the behavior of the entanglement.

  14. Monte Carlo solution methods in a moment-based scale-bridging algorithm for thermal radiative transfer problems: Comparison with Fleck and Cummings

    SciTech Connect

    Park, H.; Densmore, J. D.; Wollaber, A. B.; Knoll, D. A.; Rauenzahn, R. M.

    2013-07-01

    We have developed a moment-based scale-bridging algorithm for thermal radiative transfer problems. The algorithm takes the form of well-known nonlinear-diffusion acceleration which utilizes a low-order (LO) continuum problem to accelerate the solution of a high-order (HO) kinetic problem. The coupled nonlinear equations that form the LO problem are efficiently solved using a preconditioned Jacobian-free Newton-Krylov method. This work demonstrates the applicability of the scale-bridging algorithm with a Monte Carlo HO solver and reports the computational efficiency of the algorithm in comparison to the well-known Fleck-Cummings algorithm. (authors)

  15. Internet Cum Laude.

    ERIC Educational Resources Information Center

    Richardson, Eric C.

    1995-01-01

    Discusses the Internet's role in colleges and universities. Topics include network development, accessing the library's online catalog; attracting students, electronic student handbooks, coursework information, and program listings, teleconferencing, distance education, independent study and online degrees, electronic field trips, journalism…

  16. CUM LAUDE? So What!

    ERIC Educational Resources Information Center

    Bolin, John G.

    1975-01-01

    Presents a study to determine what trends were common and what differences could be identified in percentage of degrees granted with honors. Concludes that institutions must either move into a pass-fail approach with no honors, or return to a more dedicated approach to student evaluation. (Author/PG)

  17. Entanglement transfer from two-mode continuous variable SU(2) cat states to discrete qubits systems in Jaynes-Cummings Dimers

    PubMed Central

    Ran, Du; Hu, Chang-Sheng; Yang, Zhen-Biao

    2016-01-01

    We study the entanglement transfer from a two-mode continuous variable system (initially in the two-mode SU(2) cat states) to a couple of discrete two-state systems (initially in an arbitrary mixed state), by use of the resonant Jaynes-Cummings (JC) interaction. We first quantitatively connect the entanglement transfer to non-Gaussianity of the two-mode SU(2) cat states and find a positive correlation between them. We then investigate the behaviors of the entanglement transfer and find that it is dependent on the initial state of the discrete systems. We also find that the largest possible value of the transferred entanglement exhibits a variety of behaviors for different photon number as well as for the phase angle of the two-mode SU(2) cat states. We finally consider the influences of the noise on the transferred entanglement. PMID:27553881

  18. Entanglement transfer from two-mode continuous variable SU(2) cat states to discrete qubits systems in Jaynes-Cummings Dimers.

    PubMed

    Ran, Du; Hu, Chang-Sheng; Yang, Zhen-Biao

    2016-01-01

    We study the entanglement transfer from a two-mode continuous variable system (initially in the two-mode SU(2) cat states) to a couple of discrete two-state systems (initially in an arbitrary mixed state), by use of the resonant Jaynes-Cummings (JC) interaction. We first quantitatively connect the entanglement transfer to non-Gaussianity of the two-mode SU(2) cat states and find a positive correlation between them. We then investigate the behaviors of the entanglement transfer and find that it is dependent on the initial state of the discrete systems. We also find that the largest possible value of the transferred entanglement exhibits a variety of behaviors for different photon number as well as for the phase angle of the two-mode SU(2) cat states. We finally consider the influences of the noise on the transferred entanglement. PMID:27553881

  19. ELECTROMAGNETISM, OPTICS, ACOUSTICS, HEAT TRANSFER, CLASSICAL MECHANICS, AND FLUID DYNAMICS: Entropy and Entanglement in Master Equation of Effective Hamiltonian for Jaynes-Cummings Model

    NASA Astrophysics Data System (ADS)

    Hessian, H. A.; Mohammed, F. A.; Mohamed, A.-B. A.

    2009-04-01

    In this paper, we analytically solve the master equation for Jaynes-Cummings model in the dispersive regime including phase damping and the field is assumed to be initially in a superposition of coherent states. Using an established entanglement measure based on the negativity of the eigenvalues of the partially transposed density matrix we find a very strong sensitivity of the maximally generated entanglement to the amount of phase damping. Qualitatively this behavior is also reflected in alternative entanglement measures, but the quantitative agreement between different measures depends on the chosen noise model. The phase decoherence for this model results in monotonic increase in the total entropy while the atomic sub-entropy keeps its periodic behaviour without any effect.

  20. Cosmic Complexity

    NASA Technical Reports Server (NTRS)

    Mather, John C.

    2012-01-01

    neutrons, liberating a little energy and creating complexity. Then, the expanding universe cooled some more, and neutrons and protons, no longer kept apart by immense temperatures, found themselves unstable and formed helium nuclei. Then, a little more cooling, and atomic nuclei and electrons were no longer kept apart, and the universe became transparent. Then a little more cooling, and the next instability began: gravitation pulled matter together across cosmic distances to form stars and galaxies. This instability is described as a "negative heat capadty" in which extracting energy from a gravitating system makes it hotter -- clearly the 2nd law of thermodynamics does not apply here! (This is the physicist's part of the answer to e e cummings' question: what is the wonder that's keeping the stars apart?) Then, the next instability is that hydrogen and helium nuclei can fuse together to release energy and make stars burn for billions of years. And then at the end of the fuel source, stars become unstable and explode and liberate the chemical elements back into space. And because of that, on planets like Earth, sustained energy flows support the development of additional instabilities and all kinds of complex patterns. Gravitational instability pulls the densest materials into the core of the Earth, leaving a thin skin of water and air, and makes the interior churn incessantly as heat flows outwards. And the heat from the sun, received mostly near the equator and flowing towards the poles, supports the complex atmospheric and oceanic circulations. And because or that, the physical Earth is full of natural chemical laboratories, concentrating elements here, mixing them there, raising and lowering temperatures, ceaselessly experimenting with uncountable events where new instabilities can arise. At least one of them was the new experiment called life. Now that we know that there are at least as many planets as there are stars, it is hard to imagine that nature's ceasess

  1. Cosmic Complexity

    NASA Technical Reports Server (NTRS)

    Mather, John C.

    2012-01-01

    neutrons, liberating a little energy and creating complexity. Then, the expanding universe cooled some more, and neutrons and protons, no longer kept apart by immense temperatures, found themselves unstable and formed helium nuclei. Then, a little more cooling, and atomic nuclei and electrons were no longer kept apart, and the universe became transparent. Then a little more cooling, and the next instability began: gravitation pulled matter together across cosmic distances to form stars and galaxies. This instability is described as a "negative heat capadty" in which extracting energy from a gravitating system makes it hotter -- clearly the 2nd law of thermodynamics does not apply here! (This is the physicist's part of the answer to e e cummings' question: what is the wonder that's keeping the stars apart?) Then, the next instability is that hydrogen and helium nuclei can fuse together to release energy and make stars burn for billions of years. And then at the end of the fuel source, stars become unstable and explode and liberate the chemical elements back into space. And because of that, on planets like Earth, sustained energy flows support the development of additional instabilities and all kinds of complex patterns. Gravitational instability pulls the densest materials into the core of the Earth, leaving a thin skin of water and air, and makes the interior churn incessantly as heat flows outwards. And the heat from the sun, received mostly near the equator and flowing towards the poles, supports the complex atmospheric and oceanic circulations. And because or that, the physical Earth is full of natural chemical laboratories, concentrating elements here, mixing them there, raising and lowering temperatures, ceaselessly experimenting with uncountable events where new instabilities can arise. At least one of them was the new experiment called life. Now that we know that there are at least as many planets as there are stars, it is hard to imagine that nature's ceasess

  2. Evolution of Palaeoproterozoic mafic intrusions located within the thermal aureole of the Sudbury Igneous Complex, Canada: Isotopic, geochronological and geochemical evidence

    NASA Astrophysics Data System (ADS)

    Prevec, Stephen A.; Baadsgaard, Halfdan

    2005-07-01

    Impact cratering and their resultant geological phenomena are recognised as significant factors in the lithological and biologic evolution of the earth. Age-dating of impact events is critical in correlating cause and effects for these catastrophic processes. The Falconbridge and Drury Township (Twp) intrusions were emplaced at the contact between Neoarchaean basement and Palaeoproterozoic volcanosedimentary rocks, and also lie at the southeast and southwest edges of the Sudbury Igneous Complex (SIC), within its thermal contact aureole. The Falconbridge Twp intrusion is dated at 2441 ± 3 Ma by U-Pb zircon, with evidence of Archaean inheritance from its host granitoids. Granitoids from the southernmost Abitibi Subprovince are dated here between 2670 ± 11 Ma for an undeformed Algoman granite, and 2696 ± 18 Ma for a foliated granitoid, consistent with existing data from the Abitibi Greenstone Belt and from the Wawa Subprovince. Major and trace element geochemical evidence, common-Pb isotopic compositions, and ɛNd2440 values between 0 and -1 are all consistent with a Palaeoproterozoic origin for the Falconbridge Twp intrusion, and support inclusion in the East Bull Lake-type suite of leucogabbroic plutons and sills. In contrast, the Drury Twp intrusion gives a U-Pb zircon age of 1859 ± 13 Ma, coincident with the date of SIC-emplacement. While the major and trace element compositions are comparable to the Falconbridge data, the Drury displays significant heterogeneity in ɛNd2440, with values ranging from +3.7 to -0.1, and contains more radiogenic Pb isotopic compositions. Field, geochemical and isotopic evidence clearly distinguishes this intrusion from constituents of the SIC itself, and indicates that the Drury too is a Palaeoproterozoic intrusion. This requires that apparently unshocked, undeformed magmatic-looking zircon has been grown or reset in a postmagmatic setting. This has significant implications for the identification of mantle-derived magmas and

  3. Improvement of Asthma and Gastroesophageal Reflux Disease With Oral Pulvis stomachicus cum Belladonna, a Combination of Matricaria recutita, Atropa belladonna, Bismuth, and Antimonite: A Pediatric Case Report

    PubMed Central

    Madeleyn, René; Kiene, Helmut; Kienle, Gunver S.; Vagedes, Jan

    2016-01-01

    The association between gastroesophageal reflux disease (GERD) and asthma, although well established in adults, is less strong in the pediatric age group. Benefits of proton pump therapy are limited across age ranges. While there is a growing body of literature on the use of complementary treatments for both asthma and GERD, few studies have focused on treatment benefits for the GERD-asthma association. We present the case of a 2-year-old boy with asthma and GERD who was not responding to inhaled, low-dose corticosteroids, beta-mimetic therapy, and a 6-week course of proton pump inhibitor treatment. We noted a gradual disappearance of symptoms when he was given an oral preparation of Pulvis stomachicus cum Belladonna, an anthroposophic medication containing Matricaria recutita, Atropa belladonna, bismuth, and antimonite. Matricaria recutita and bismuth have known gastric protective properties, and Atropa belladonna contains anticholinergic agents that have a bronchodilatory effect. These complementary medications appear promising in terms of relieving the symptoms of GERD-associated asthma. PMID:26937321

  4. Improvement of Asthma and Gastroesophageal Reflux Disease With Oral Pulvis stomachicus cum Belladonna, a Combination of Matricaria recutita, Atropa belladonna, Bismuth, and Antimonite: A Pediatric Case Report.

    PubMed

    von Schoen-Angerer, Tido; Madeleyn, René; Kiene, Helmut; Kienle, Gunver S; Vagedes, Jan

    2016-01-01

    The association between gastroesophageal reflux disease (GERD) and asthma, although well established in adults, is less strong in the pediatric age group. Benefits of proton pump therapy are limited across age ranges. While there is a growing body of literature on the use of complementary treatments for both asthma and GERD, few studies have focused on treatment benefits for the GERD-asthma association. We present the case of a 2-year-old boy with asthma and GERD who was not responding to inhaled, low-dose corticosteroids, beta-mimetic therapy, and a 6-week course of proton pump inhibitor treatment. We noted a gradual disappearance of symptoms when he was given an oral preparation of Pulvis stomachicus cum Belladonna, an anthroposophic medication containing Matricaria recutita, Atropa belladonna, bismuth, and antimonite. Matricaria recutita and bismuth have known gastric protective properties, and Atropa belladonna contains anticholinergic agents that have a bronchodilatory effect. These complementary medications appear promising in terms of relieving the symptoms of GERD-associated asthma. PMID:26937321

  5. Comparative analysis of the constituents in Saposhnikoviae Radix and Glehniae Radix cum Rhizoma by monitoring inhibitory activity of nitric oxide production.

    PubMed

    Kamino, Takuya; Shimokura, Toshihiro; Morita, Yusuke; Tezuka, Yasuhiro; Nishizawa, Mikio; Tanaka, Ken

    2016-04-01

    During the development of natural herbal medicines in Japan, Glehniae Radix cum Rhizoma (Hamabofu in Japanese) has been used as a substitute for Saposhnikoviae Radix (Bofu). Bofu and Hamabofu are blended differently in several Kampo formulae. For example, Bofu is included in Jumihaidokuto by a manufacturer, whereas Hamabofu is included instead of Bofu in the same formula by other manufacturers. Although both Bofu and Hamabofu are used for their expected anti-inflammatory effects, differences in their medicinal properties are not well characterized. In addition, there have been very few reports comparing the pharmacological activities of the constituents in Bofu and Hamabofu. In the present study, we investigated the anti-inflammatory effects of the extracts of Bofu and Hamabofu by monitoring levels of the inflammatory mediator nitric oxide (NO) produced in rat hepatocytes. Moreover, the chemical constituents responsible for the activity were investigated. Our results showed that ethyl acetate fractions of Bofu and Hamabofu extracts contain different compounds, although both fractions suppressed NO production in rat hepatocytes. The linear dihydropyranochromones from the Bofu extract (i.e., 3'-O-angeloylhamaudol, ledebouriellol and hamaudol) suppressed NO production, whereas the coumarins from the Hamabofu extract (i.e., umbelliferone and scopoletin) also suppressed NO production. These results suggest that linear dihydropyranochromones and coumarins are responsible for the anti-inflammatory effects of Bofu and Hamabofu. It is plausible that Bofu and Hamabofu are blended differently in several Kampo formulae due to many constituents with as yet unidentified pharmacological activity. PMID:26833192

  6. Synthesis, crystal and electronic structure of the quaternary sulfides Ln2CuMS5 (Ln=La, Ce; M=Sb, Bi)

    NASA Astrophysics Data System (ADS)

    Kussainova, Ardak M.; Akselrud, Lev G.; Suen, Nian-Tzu; Voss, Leonard; Stoyko, Stanislav; Bobev, Svilen

    2016-01-01

    The series of quaternary sulfides with general formula Ln2CuMS5 (Ln=La, Ce; M=Sb, Bi) have been synthesized by solid-state reactions. Three representative members have been structurally characterized by single-crystal X-ray diffraction. La2CuSbS5 crystallizes in a new structure type (space group Ima2 (no. 46), Z=4, a=13.401(2) Å, b=7.592(1) Å, c=7.598(1) Å, V=773.1(3) Å3). The bismuth analogs of composition La2CuBiS5 and Ce2CuBiS5 crystallize with the La2CuInSe5 structure type (space group Pnma (no. 62), Z=4). Lattice parameters for La2CuBiS5: a=11.9213(5) Å, b=3.9967(2) Å, c=17.0537(8) Å, V=812.56(7) Å3; lattice parameters for Ce2CuBiS5: a=11.9179(15) Å, b=3.9596(5) Å, c=16.955(2) Å, V=800.13(17) Å3). The similarities and the differences between the two structures are discussed. Electronic structure calculations for La2CuSbS5 and La2CuBiS5 are also presented; they suggest semiconducting behavior with energy gaps exceeding 1.7 eV.

  7. Entropy squeezing and atomic inversion in the k-photon Jaynes—Cummings model in the presence of the Stark shift and a Kerr medium: A full nonlinear approach

    NASA Astrophysics Data System (ADS)

    H, R. Baghshahi; M, K. Tavassoly; A, Behjat

    2014-07-01

    The interaction between a two-level atom and a single-mode field in the k-photon Jaynes—Cummings model (JCM) in the presence of the Stark shift and a Kerr medium is studied. All terms in the Hamiltonian, such as the single-mode field, its interaction with the atom, the contribution of the Stark shift and the Kerr medium effects are considered to be f-deformed. In particular, the effect of the initial state of the radiation field on the dynamical evolution of some physical properties such as atomic inversion and entropy squeezing are investigated by considering different initial field states (coherent, squeezed and thermal states).

  8. High resolution positron annihilation induced Auger electron spectroscopy of the CuM 2,3VV-transition and of Cu sub-monolayers on Pd and Fe

    NASA Astrophysics Data System (ADS)

    Mayer, J.; Hugenschmidt, C.; Schreckenbach, K.

    2010-09-01

    We present a high resolution positron annihilation induced Auger Electron Spectroscopy (PAES) of the CuM 2,3VV-transition with the unprecedented energy resolution of Δ/EE <1%. This energy resolution and the highly intense positron source NEPOMUC enabled us to resolve the double peak structure with PAES for the first time within a measurement time of only 5.5 h. In addition, sub-monolayers of Cu were deposited on Fe- and Pd-samples in order to investigate the surface selectivity of PAES in comparison with EAES. The extremely high surface selectivity of PAES due to the different positron affinity of Cu and Fe lead to the result that with only 0.96 monolayer of Cu on Fe more than 55% of the emitted Auger electrons stem from Cu, whereas with EAES the Cu Auger fraction amounted to less than 6%.

  9. ELECTROMAGNETISM, OPTICS, ACOUSTICS, HEAT TRANSFER, CLASSICAL MECHANICS, AND FLUID DYNAMICS: Properties of Linear Entropy in k-Photon Jaynes-Cummings Model with Stark Shift and Kerr-Like Medium

    NASA Astrophysics Data System (ADS)

    Liao, Qing-Hong; Ashfaq Ahmad, Muhammad; Wang, Yue-Yuan; Liu, Shu-Tian

    2010-05-01

    The time evolution of the linear entropy of an atom in k-photon Jaynes-Cummings model is investigated taking into consideration Stark shift and Kerr-like medium. The effect of both the Stark shift and Kerr-like medium on the linear entropy is analyzed using a numerical technique for the field initially in coherent state and in even coherent state. The results show that the presence of the Kerr-like medium and Stark shift has an important effect on the properties of the entropy and entanglement. It is also shown that the setting of the initial state plays a significant role in the evolution of the linear entropy and entanglement.

  10. Sulfur-rich zinc chemistry: new tris(thioimidazolyl)hydroborate ligands and their zinc complex chemistry related to the structure and function of alcohol dehydrogenase.

    PubMed

    Tesmer, M; Shu, M; Vahrenkamp, H

    2001-07-30

    The 1-substituted tris(2-thioimidazolyl)hydroborate ligands Tt(R) were prepared as the potassium salts from KBH(4) and the corresponding 1-R-2-thioimidazole for R = t-Bu and C(6)H(4)-p-CH(CH(3))(2) (Cum). Their reactions with zinc salts yielded the tetrahedral complexes Tt(R)Zn-X with X = F, Cl, ONO(2) and (Tt(t)()(-)(Bu))(2)Zn. With zinc perchlorate the labile perchlorate complexes Tt(R)Zn-OClO(3) were obtained. They served as starting materials for the incorporation of substrates which are relevant for the chemistry of horse liver alcohol dehydrogenase: Ethanol led to [Tt(t)()(-Bu)Zn.EtOH] ClO(4).EtOH, p-nitrophenol (NitOH) yielded Tt(Cum)Zn-ONit. Pyridine-2-carbaldehyde and salicylic aldehyde were incorporated as N(pyridine) and O(phenolate) coligands with possible additional O(aldehyde) coordination. Substituted pyridyl methanols (R-PyCH(2)OH) yielded the trinuclear complexes [(Tt(t)()(-Bu))(2)Zn(3)(R-PyCH(2)O)(2)] (ClO(4))(2) with bridging Tt and pyridylmethoxide ligands. Preliminary experiments on the functional modeling of alcohol dehydrogenase have shown that TtZn complexes promote both the dehydrogenation of 2-propanol and the hydrogenation of pentafluorobenzaldehyde. PMID:11466063

  11. New CuM 2/3Sb 1/3O 2 and AgM 2/3Sb 1/3O 2 compounds with the delafossite structure

    NASA Astrophysics Data System (ADS)

    Nagarajan, R.; Uma, S.; Jayaraj, M. K.; Tate, J.; Sleight, A. W.

    2002-05-01

    Several new compounds have been prepared with the delafossite structure: CuMn 2/3Sb 1/3O 2, CuCo 2/3Sb 1/3O 2, CuNi 2/3Sb 1/3O 2, CuZn 2/3Sb 1/3O 2, CuMg 2/3Sb 1/3O 2, AgNi 2/3Sb 1/3O 2, and AgZn 2/3Sb 1/3O 2. The structures of the CuM 2/3Sb 1/3O 2 compounds are generally based on 2H stacking along the c axis, and the M 2+ and Sb 5+ cations can be ordered or disordered. The structures of the AgM 2/3Sb 1/3O 2 compounds are based on 3R stacking along c with the M 2+ and Sb 5+ cations disordered. The structures of CuMn 2/3Sb 1/3O 2 (disordered) and CuMg 2/3Sb 1/3O 2 (ordered) were refined from single crystal X-ray diffraction data. Pellets and transparent thin films of CuNi 2/3Sb 1/3O 2 with 10% Sn doping for Sb showed p-type electronic conduction.

  12. Complexity Survey.

    ERIC Educational Resources Information Center

    Gordon, Sandra L.; Anderson, Beth C.

    To determine whether consensus existed among teachers about the complexity of common classroom materials, a survey was administered to 66 pre-service and in-service kindergarten and prekindergarten teachers. Participants were asked to rate 14 common classroom materials as simple, complex, or super-complex. Simple materials have one obvious part,…

  13. Communication complexity and information complexity

    NASA Astrophysics Data System (ADS)

    Pankratov, Denis

    Information complexity enables the use of information-theoretic tools in communication complexity theory. Prior to the results presented in this thesis, information complexity was mainly used for proving lower bounds and direct-sum theorems in the setting of communication complexity. We present three results that demonstrate new connections between information complexity and communication complexity. In the first contribution we thoroughly study the information complexity of the smallest nontrivial two-party function: the AND function. While computing the communication complexity of AND is trivial, computing its exact information complexity presents a major technical challenge. In overcoming this challenge, we reveal that information complexity gives rise to rich geometrical structures. Our analysis of information complexity relies on new analytic techniques and new characterizations of communication protocols. We also uncover a connection of information complexity to the theory of elliptic partial differential equations. Once we compute the exact information complexity of AND, we can compute exact communication complexity of several related functions on n-bit inputs with some additional technical work. Previous combinatorial and algebraic techniques could only prove bounds of the form theta( n). Interestingly, this level of precision is typical in the area of information theory, so our result demonstrates that this meta-property of precise bounds carries over to information complexity and in certain cases even to communication complexity. Our result does not only strengthen the lower bound on communication complexity of disjointness by making it more exact, but it also shows that information complexity provides the exact upper bound on communication complexity. In fact, this result is more general and applies to a whole class of communication problems. In the second contribution, we use self-reduction methods to prove strong lower bounds on the information

  14. Complex derivatives

    NASA Astrophysics Data System (ADS)

    Battiston, Stefano; Caldarelli, Guido; Georg, Co-Pierre; May, Robert; Stiglitz, Joseph

    2013-03-01

    The intrinsic complexity of the financial derivatives market has emerged as both an incentive to engage in it, and a key source of its inherent instability. Regulators now faced with the challenge of taming this beast may find inspiration in the budding science of complex systems.

  15. Designing Complexity

    ERIC Educational Resources Information Center

    Glanville, Ranulph

    2007-01-01

    This article considers the nature of complexity and design, as well as relationships between the two, and suggests that design may have much potential as an approach to improving human performance in situations seen as complex. It is developed against two backgrounds. The first is a world view that derives from second order cybernetics and radical…

  16. Carney Complex

    MedlinePlus

    ... Screening guidelines may change over time as new technologies are developed and more is learned about Carney complex. It is important to talk with your doctor about appropriate screening tests. Learn more about what to expect when having ...

  17. Complex networks: Patterns of complexity

    NASA Astrophysics Data System (ADS)

    Pastor-Satorras, Romualdo; Vespignani, Alessandro

    2010-07-01

    The Turing mechanism provides a paradigm for the spontaneous generation of patterns in reaction-diffusion systems. A framework that describes Turing-pattern formation in the context of complex networks should provide a new basis for studying the phenomenon.

  18. Complex interactions

    NASA Astrophysics Data System (ADS)

    de Régules, Sergio

    2016-04-01

    Complexity science – which describes phenomena such as collective and emergent behaviour – is the focus of a new centre where researchers are examining everything from the spread of influenza to what a healthy heartbeat looks like. Sergio de Régules reports.

  19. Researching Complexity.

    ERIC Educational Resources Information Center

    Sumara, Dennis J.

    2000-01-01

    Discusses what Complexity Theory (presented as a rubric that collects theoretical understandings from a number of domains such as ecology, biology, neurology, and education) suggests about mind, selfhood, intelligence, and practices of reading, and the import of these reconceptualizations to reader-response researchers. Concludes that developing…

  20. Complex Clouds

    Atmospheric Science Data Center

    2013-04-16

    ...     View Larger Image The complex structure and beauty of polar clouds are highlighted by these images acquired ... Multi-angle Imaging SpectroRadiometer observes the daylit Earth continuously from pole to pole, and every 9 days views the entire globe ...

  1. Amorphic complexity

    NASA Astrophysics Data System (ADS)

    Fuhrmann, G.; Gröger, M.; Jäger, T.

    2016-02-01

    We introduce amorphic complexity as a new topological invariant that measures the complexity of dynamical systems in the regime of zero entropy. Its main purpose is to detect the very onset of disorder in the asymptotic behaviour. For instance, it gives positive value to Denjoy examples on the circle and Sturmian subshifts, while being zero for all isometries and Morse-Smale systems. After discussing basic properties and examples, we show that amorphic complexity and the underlying asymptotic separation numbers can be used to distinguish almost automorphic minimal systems from equicontinuous ones. For symbolic systems, amorphic complexity equals the box dimension of the associated Besicovitch space. In this context, we concentrate on regular Toeplitz flows and give a detailed description of the relation to the scaling behaviour of the densities of the p-skeletons. Finally, we take a look at strange non-chaotic attractors appearing in so-called pinched skew product systems. Continuous-time systems, more general group actions and the application to cut and project quasicrystals will be treated in subsequent work.

  2. Symmetry-cum-Unification in physical theories

    NASA Astrophysics Data System (ADS)

    Mitra, A. N.

    2014-06-01

    A new kind of duality in physical sciences-involving Symmetry (S)on the one hand and Unification(U) on the other- is proposed, wherein the two partners obey, not the traditional feature of mutual incompatibility of two canonically conjugate variables, but rather are bound by a cause-effect type of relationship, albeit at a probabilistic level. While a precise mathematical formulation of such relationship is still a distant goal, the possible impact of this new kind of duality on the growth of physical theories vis-a-vis experiment is envisaged.

  3. Managing Complexity

    SciTech Connect

    Chassin, David P.; Posse, Christian; Malard, Joel M.

    2004-08-01

    Physical analogs have shown considerable promise for understanding the behavior of complex adaptive systems, including macroeconomics, biological systems, social networks, and electric power markets. Many of today’s most challenging technical and policy questions can be reduced to a distributed economic control problem. Indeed, economically-based control of large-scale systems is founded on the conjecture that the price-based regulation (e.g., auctions, markets) results in an optimal allocation of resources and emergent optimal system control. This paper explores the state of the art in the use physical analogs for understanding the behavior of some econophysical systems and to deriving stable and robust control strategies for them. In particular we review and discussion applications of some analytic methods based on the thermodynamic metaphor according to which the interplay between system entropy and conservation laws gives rise to intuitive and governing global properties of complex systems that cannot be otherwise understood.

  4. Measurement of Absolute Fission Yields in the Fast Neutron-Induced Fission of Actinides: {sup 238}U, {sup 237}Np, {sup 238}Pu, {sup 240}Pu, {sup 243}Am, and {sup 244}Cm by Track-Etch-cum-Gamma Spectrometry

    SciTech Connect

    Iyer, R.H.; Naik, H.; Pandey, A.K.; Kalsi, P.C.; Singh, R.J.; Ramaswami, A.; Nair, A.G.C.

    2000-07-15

    The absolute fission yields of 46 fission products in {sup 238}U (99.9997 at.%), 46 fission products in {sup 237}Np, 27 fission products in {sup 238}Pu (99.21 at.%), 30 fission products in {sup 240}Pu (99.48 at.%), 30 fission products in {sup 243}Am (99.998 at.%), and 32 fission products in {sup 244}Cm (99.43 at.%) induced by fast neutrons were determined using a fission track-etch-cum-gamma spectrometric technique. In the case of highly alpha-active and sparingly available actinides - e.g., {sup 238}Pu, {sup 240}Pu, {sup 243}Am, and {sup 244}Cm - a novel recoil catcher technique to collect the fission products on a Lexan polycarbonate foil followed by gamma-ray spectrometry was developed during the course of this work. This completely removed interferences from (a) gamma rays of daughter products in secular equilibrium with the target nuclide (e.g., {sup 243}Am-{sup 239}Np), (b) activation products of the catcher foil [e.g., {sup 24}Na from Al(n,{alpha})], and (c) activation products of the target [e.g., {sup 238}Np from {sup 237}Np(n,{gamma}) and {sup 239}Np from {sup 238}U(n,{gamma})] reactions, making the gamma spectrometric analysis very simple and accurate. The high-yield asymmetric fission products were analyzed by direct gamma spectrometry, whereas the low-yield symmetric products (e.g., Ag, Cd, and Sb) as well as some of the asymmetric fission products (e.g., Br) and rare earths (in the case of {sup 238}U and {sup 237}Np) were radiochemically separated and then analyzed by gamma-ray spectrometry. The neutron spectra in the irradiation positions of the reactors were measured and delineated in the thermal to 10-MeV region using threshold activation detectors. The present data were compared with the ENDF/VI and UKFY2 evaluated data files. From the measured cumulative yields, the mass-chain yields have been deduced using charge distribution systematics. The mass yields, along with similar data for other fast neutron-induced fissioning systems, show several

  5. Complex Systems

    PubMed Central

    Goldberger, Ary L.

    2006-01-01

    Physiologic systems in health and disease display an extraordinary range of temporal behaviors and structural patterns that defy understanding based on linear constructs, reductionist strategies, and classical homeostasis. Application of concepts and computational tools derived from the contemporary study of complex systems, including nonlinear dynamics, fractals and “chaos theory,” is having an increasing impact on biology and medicine. This presentation provides a brief overview of an emerging area of biomedical research, including recent applications to cardiopulmonary medicine and chronic obstructive lung disease. PMID:16921107

  6. [Carney complex].

    PubMed

    Kacerovská, D; Michal, M; Síma, R; Grossmann, P; Kazakov, D V

    2011-10-01

    Carney complex is a clinically and genetically heterogeneous disease, with at least two genetic loci including the PRKAR1A gene located on chromosome 17 and the CNC2 locus mapped to chromosome 2. Clinically this syndrome is characterized by multiple myxomas occurring in different anatomic sites, mucocutaneous pigmentary lesions, and a variety of non-endocrine and endocrine tumors, often causing endocrine abnormalities, involving various organs. Knowledge of morphological findings in CNC patients with their typical locations is necessary to raise suspicion of this syndrome by pathologists. Confirmation of the diagnosis allows regular clinical check-ups and early treatment of these patients. PMID:22145222

  7. Carney complex.

    PubMed

    Espiard, Stéphanie; Bertherat, Jérôme

    2013-01-01

    Carney complex is a rare, dominantly inherited multiple endocrine neoplasia syndrome, affecting endocrine glands as the adrenal cortex (causing Cushing's syndrome), the pituitary and the thyroid. It is associated with many other nonendocrine tumors, including cardiac myxomas, testicular tumors, melanotic schwannoma, breast myxomatosis, and abnormal pigmentation (lentiginosis) or myxomas of the skin. The gene located on the CNC1 locus was identified 12 years ago as the regulatory subunit 1A (R1A) of the protein kinase A (PRKAR1A) located at 17q22-24. Inactivating heterozygous germline mutations of PRKAR1A are observed in about two thirds of Carney complex patients with some genotype-phenotype correlation useful for follow-up and prognosis. More rarely, mutations of phosphodiesterase genes have been reported in patients presenting mainly with Cushing's syndrome. In vitro and in vivo studies help to understand how R1A inactivation leads to tumorigenesis. PRKAR1A appears to be a relatively weak tumorigenic signal which can cooperate with other signaling pathways and tumor suppressors. PMID:23652670

  8. Synthesis, structure and biological activity of nickel(II) complexes of 5-methyl 2-furfural thiosemicarbazone.

    PubMed

    Jouad, E M; Larcher, G; Allain, M; Riou, A; Bouet, G M; Khan, M A; Thanh, X D

    2001-09-01

    5-Methyl 2-furfuraldehyde thiosemicarbazone (M5HFTSC) with nickel(II) leads to three types of complexes: [Ni(M5HFTSC)(2)X(2)], [Ni(M5FTSC)(2)] and [Ni(M5FTSC)(2)] x 2DMF. In the first type the ligand remains in thione form, while in the two other, the anionic thiolato form is involved. The species [Ni(M5HFTSC)(2)X(2)] has been characterized spectroscopically. The structures of [Ni(M5FTSC)(2)] x 2DMF and [Ni(M5FTSC)(2)] have been solved using X-ray diffraction. Biological studies of [Ni(M5HFTSC)(2)Cl(2)] have been carried out in vitro for antifungal activity on human pathogenic fungi, Aspergillus fumigatus and Candida albicans, and in vivo for toxicity on mice. The results are compared to those of the ligand, the metal salt and a similar copper complex [Cu(M5HFTSC)Cl(2)]. PMID:11566328

  9. [Carney complex].

    PubMed

    Losada Grande, Eladio José; Al Kassam Martínez, Daniel; González Boillos, Margarita

    2011-01-01

    Carney complex (CNC) is an autosomal dominantly inherited syndrome characterized by spotty skin pigmentation, cardiac and cutaneous myxoma, and endocrine overactivity. Skin pigmentation includes lentigines and blue nevi. Myxomas may occur in breast, skin and heart. Cardiac myxomas may be multiple and occur in any cardiac chamber, and are more prone to recurrence. The most common endocrine gland manifestation is an ACTH-independent Cushing's syndrome due to primary pigmented nodular adrenocortical disease (PPNAD). PPNAD may occur isolated, with no other signs of CNC. Pituitary and thyroid glands and gonads are also involved. The PRKAR1A gene, located in 17 q22-24, encodes type 1A regulatory subunit of protein kinase A. Inactivating germline mutations of this gene are found in 70% of patients with CNC. PRKAR1A is a key component of the c-AMP signaling pathway that has been implicated in endocrine tumorigenesis. Many different mutations have been reported in the PRKAR1A gene. In almost all cases the sequence change was predicted to lead to a premature stop codon and the resultant mutant mRNA was subject to nonsense-mediated mRNA decay. There is no clear genotype-phenotype correlation in patients with CNC. Genetic analysis should be performed in all CNC index cases. All affected patients should be monitored for clinical signs of CNC at least once a year. Genetic diagnosis allows for more effective preparation of more appropriate and effective therapeutic strategies and genetic counseling for patients and gene carriers, and to avoid unnecessary tests to relatives not carrying the gene. PMID:21536508

  10. Complex-plane generalization of scalar Levin transforms: A robust, rapidly convergent method to compute potentials and fields in multi-layered media

    NASA Astrophysics Data System (ADS)

    Sainath, Kamalesh; Teixeira, Fernando L.; Donderici, Burkay

    2014-07-01

    We propose the complex-plane generalization of a powerful algebraic sequence acceleration algorithm, the method of weighted averages (MWA), to guarantee exponential-cum-algebraic convergence of Fourier and Fourier-Hankel (F-H) integral transforms. This “complex-plane” MWA, effected via a linear-path detour in the complex plane, results in rapid, absolute convergence of field and potential solutions in multi-layered environments regardless of the source-observer geometry and anisotropy/loss of the media present. In this work, we first introduce a new integration path used to evaluate the field contribution arising from the radiation spectra. Subsequently, we (1) exhibit the foundational relations behind the complex-plane extension to a general Levin-type sequence convergence accelerator, (2) specialize this analysis to one member of the Levin transform family (the MWA), (3) address and circumvent restrictions, arising for two-dimensional integrals associated with wave dynamics problems, through minimal complex-plane detour restrictions and a novel partition of the integration domain, (4) develop and compare two formulations based on standard/real-axis MWA variants, and (5) present validation results and convergence characteristics for one of these two formulations.

  11. Complex-plane generalization of scalar Levin transforms: A robust, rapidly convergent method to compute potentials and fields in multi-layered media

    SciTech Connect

    Sainath, Kamalesh; Teixeira, Fernando L.; Donderici, Burkay

    2014-07-15

    We propose the complex-plane generalization of a powerful algebraic sequence acceleration algorithm, the method of weighted averages (MWA), to guarantee exponential-cum-algebraic convergence of Fourier and Fourier–Hankel (F–H) integral transforms. This “complex-plane” MWA, effected via a linear-path detour in the complex plane, results in rapid, absolute convergence of field and potential solutions in multi-layered environments regardless of the source-observer geometry and anisotropy/loss of the media present. In this work, we first introduce a new integration path used to evaluate the field contribution arising from the radiation spectra. Subsequently, we (1) exhibit the foundational relations behind the complex-plane extension to a general Levin-type sequence convergence accelerator, (2) specialize this analysis to one member of the Levin transform family (the MWA), (3) address and circumvent restrictions, arising for two-dimensional integrals associated with wave dynamics problems, through minimal complex-plane detour restrictions and a novel partition of the integration domain, (4) develop and compare two formulations based on standard/real-axis MWA variants, and (5) present validation results and convergence characteristics for one of these two formulations.

  12. On State Complexes and Special Cube Complexes

    ERIC Educational Resources Information Center

    Peterson, Valerie J.

    2009-01-01

    This thesis presents the first steps toward a classification of non-positively curved cube complexes called state complexes. A "state complex" is a configuration space for a "reconfigurable system," i.e., an abstract system in which local movements occur in some discrete manner. Reconfigurable systems can be used to describe, for example,…

  13. The Influence of Assessor Training on Rater-as-Interlocutor Behaviour during a Computer-Resourced Oral Proficiency Interview-Cum-Discussion (OPI/D) Known as the "Five Star Test." Paper II.

    ERIC Educational Resources Information Center

    Pollard, John D. E.

    This paper considers the influence of the values and the discourse behaviors of the native-speaking assessor as interlocutor. These variables in the assessments of oral proficiency interrelate in complex ways with features of test design such as tasks, prompts, topics, guidelines, and assessor training. This paper reviews some previous studies,…

  14. Cyanobacterial NADPH dehydrogenase complexes

    SciTech Connect

    Ogawa, Teruo; Mi, Hualing

    2007-07-01

    Cyanobacteria possess functionally distinct multiple NADPH dehydrogenase (NDH-1) complexes that are essential to CO2 uptake, photosystem-1 cyclic electron transport and respiration. The unique nature of cyanobacterial NDH-1 complexes is the presence of subunits involved in CO2 uptake. Other than CO2 uptake, chloroplastic NDH-1 complex has similar role as cyanobacterial NDH-1 complexes in photosystem-1 cyclic electron transport and respiration (chlororespiration). In this mini-review we focus on the structure and function of cyanobacterial NDH-1 complexes and their phylogeny. The function of chloroplastic NDH-1 complex and characteristics of plants defective in NDH-1 are also described forcomparison.

  15. Irinotecan Lipid Complex Injection

    MedlinePlus

    Irinotecan lipid complex is used in combination with other medications to treat pancreatic cancer that has spread ... has worsened after treatment with other chemotherapy medications. Irinotecan lipid complex is in a class of antineoplastic ...

  16. Doxorubicin Lipid Complex Injection

    MedlinePlus

    Doxorubicin lipid complex is used to treat ovarian cancer that has not improved or that has worsened after treatment with other medications. Doxorubicin lipid complex is also used to treat Kaposi's sarcoma ( ...

  17. Daunorubicin Lipid Complex Injection

    MedlinePlus

    Daunorubicin lipid complex is used to treat advanced Kaposi's sarcoma (a type of cancer that causes abnormal tissue to ... body) related to acquired immunodeficiency syndrome (AIDS). Daunorubicin lipid complex is in a class of medications called ...

  18. Vincristine Lipid Complex Injection

    MedlinePlus

    Vincristine lipid complex is used to treat a certain type of acute lymphoblastic leukemia (ALL; a type of cancer ... least two different treatments with other medications. Vincristine lipid complex is in a class of medications called ...

  19. Daunorubicin Lipid Complex Injection

    MedlinePlus

    Daunorubicin lipid complex is used to treat advanced Kaposi's sarcoma (a type of cancer that causes abnormal tissue to grow on ... related to acquired immunodeficiency syndrome (AIDS). Daunorubicin lipid complex is in a class of medications called anthracyclines. ...

  20. Cytarabine Lipid Complex Injection

    MedlinePlus

    Cytarabine lipid complex is used to treat lymphomatous meningitis (a type of cancer in the covering of the spinal cord and brain). Cytarabine lipid complex is in a class of medications called antimetabolites. ...

  1. Irinotecan Lipid Complex Injection

    MedlinePlus

    Irinotecan lipid complex is used in combination with other medications to treat pancreatic cancer that has spread to other parts of ... after treatment with other chemotherapy medications. Irinotecan lipid complex is in a class of antineoplastic medications called ...

  2. Complex regional pain syndrome

    MedlinePlus

    Complex regional pain syndrome (CRPS) is a chronic pain condition that can affect any area of the ... Bailey A, Audette JF. Complex regional pain syndrome. In: Frontera ... of Physical Medicine and Rehabilitation. 2nd ed. Philadelphia, ...

  3. Doxorubicin Lipid Complex Injection

    MedlinePlus

    Doxorubicin lipid complex is used to treat ovarian cancer that has not improved or that has worsened after treatment with other medications. Doxorubicin lipid complex is also used to treat Kaposi's sarcoma (a ...

  4. Vincristine Lipid Complex Injection

    MedlinePlus

    Vincristine lipid complex is used to treat a certain type of acute lymphoblastic leukemia (ALL; a type of cancer of the ... two different treatments with other medications. Vincristine lipid complex is in a class of medications called vinca ...

  5. Oligocyclopentadienyl transition metal complexes

    SciTech Connect

    de Azevedo, Cristina G.; Vollhardt, K. Peter C.

    2002-01-18

    Synthesis, characterization, and reactivity studies of oligocyclopentadienyl transition metal complexes, namely those of fulvalene, tercyclopentadienyl, quatercyclopentadienyl, and pentacyclopentadienyl(cyclopentadienyl) are the subject of this account. Thermal-, photo-, and redox chemistries of homo- and heteropolynuclear complexes are described.

  6. Complex-I-ty in aging

    PubMed Central

    Stork, Devon A.

    2016-01-01

    The role of mitochondrial complex I in aging has been studied in both C. elegans and Drosophila, where RNAi knock down of specific complex I subunits has been shown to extend lifespan. More recently, studies in Drosophila have shown that an increase in mitochondrial activity, including complex I-like activity, can also slow aging. In this review, we discuss this apparent paradox. Improved maintenance of mitochondrial activity, mitochondrial homeostasis, may be responsible for lifespan extension in both cases. Decreased electron transport chain activity caused by reducing complex I subunit expression prompts an increase in stress response signaling that leads to enhanced mitochondrial homeostasis during aging. Increased complex I activity, as well as mitochondrial biogenesis, is expected to both directly counteract the decline in mitochondrial health that occurs during aging and may also increase cellular NAD+ levels, which have been linked to mitochondrial homeostatic mechanisms through activation of sirtuins. We suggest that manipulations that increase or decrease complex I activity both converge on improved mitochondrial homeostasis during aging, resulting in prolonged lifespan. PMID:24961226

  7. Palladium (II) Hydrazopyrazolone Complexes

    NASA Astrophysics Data System (ADS)

    El-Maraghy, Salah B.; Salib, K. A.; Stefan, Shaker L.

    1989-12-01

    Palladium (II) complexes with 1-pheny1-3-methy1-4-(arylhydrazo)-5- pyrazolone dyes were studied spectrophotometrically. Pd (II) forms 1:1 and 1:2 complexes with the ligands by the replacement of their phenolic and hydrazo protons. The ligands behave as tridentate in the 1:1 complex and as bidentate in the 1:2 complex. The sability constants of these complexes are dependent on the type of substituents in the benzene ring of the arylazo moiety.

  8. Heuristic dynamic complexity coding

    NASA Astrophysics Data System (ADS)

    Škorupa, Jozef; Slowack, Jürgen; Mys, Stefaan; Lambert, Peter; Van de Walle, Rik

    2008-04-01

    Distributed video coding is a new video coding paradigm that shifts the computational intensive motion estimation from encoder to decoder. This results in a lightweight encoder and a complex decoder, as opposed to the predictive video coding scheme (e.g., MPEG-X and H.26X) with a complex encoder and a lightweight decoder. Both schemas, however, do not have the ability to adapt to varying complexity constraints imposed by encoder and decoder, which is an essential ability for applications targeting a wide range of devices with different complexity constraints or applications with temporary variable complexity constraints. Moreover, the effect of complexity adaptation on the overall compression performance is of great importance and has not yet been investigated. To address this need, we have developed a video coding system with the possibility to adapt itself to complexity constraints by dynamically sharing the motion estimation computations between both components. On this system we have studied the effect of the complexity distribution on the compression performance. This paper describes how motion estimation can be shared using heuristic dynamic complexity and how distribution of complexity affects the overall compression performance of the system. The results show that the complexity can indeed be shared between encoder and decoder in an efficient way at acceptable rate-distortion performance.

  9. Assessing physiological complexity.

    PubMed

    Burggren, W W; Monticino, M G

    2005-09-01

    Physiologists both admire and fear complexity, but we have made relatively few attempts to understand it. Inherently complex systems are more difficult to study and less predictable. However, a deeper understanding of physiological systems can be achieved by modifying experimental design and analysis to account for complexity. We begin this essay with a tour of some mathematical views of complexity. After briefly exploring chaotic systems, information theory and emergent behavior, we reluctantly conclude that, while a mathematical view of complexity provides useful perspectives and some narrowly focused tools, there are too few generally practical take-home messages for physiologists studying complex systems. Consequently, we attempt to provide guidelines as to how complex systems might be best approached by physiologists. After describing complexity based on the sum of a physiological system's structures and processes, we highlight increasingly refined approaches based on the pattern of interactions between structures and processes. We then provide a series of examples illustrating how appreciating physiological complexity can improve physiological research, including choosing experimental models, guiding data collection, improving data interpretations and constructing more rigorous system models. Finally, we conclude with an invitation for physiologists, applied mathematicians and physicists to collaborate on describing, studying and learning from studies of physiological complexity. PMID:16109885

  10. Artistic forms and complexity.

    PubMed

    Boon, J-P; Casti, J; Taylor, R P

    2011-04-01

    We discuss the inter-relationship between various concepts of complexity by introducing a complexity 'triangle' featuring objective complexity, subjective complexity and social complexity. Their connections are explored using visual and musical compositions of art. As examples, we quantify the complexity embedded within the paintings of the Jackson Pollock and the musical works of Johann Sebastian Bach. We discuss the challenges inherent in comparisons of the spatial patterns created by Pollock and the sonic patterns created by Bach, including the differing roles that time plays in these investigations. Our results draw attention to some common intriguing characteristics suggesting 'universality' and conjecturing that the fractal nature of art might have an intrinsic value of more general significance. PMID:21382264

  11. Hypergraph coloring complexes.

    PubMed

    Breuer, Felix; Dall, Aaron; Kubitzke, Martina

    2012-08-28

    The aim of this paper is to generalize the notion of the coloring complex of a graph to hypergraphs. We present three different interpretations of those complexes-a purely combinatorial one and two geometric ones. It is shown, that most of the properties, which are known to be true for coloring complexes of graphs, break down in this more general setting, e.g., Cohen-Macaulayness and partitionability. Nevertheless, we are able to provide bounds for the [Formula: see text]- and [Formula: see text]-vectors of those complexes which yield new bounds on chromatic polynomials of hypergraphs. Moreover, though it is proven that the coloring complex of a hypergraph has a wedge decomposition, we provide an example showing that in general this decomposition is not homotopy equivalent to a wedge of spheres. In addition, we can completely characterize those hypergraphs whose coloring complex is connected. PMID:23483700

  12. Two giant stellar complexes

    NASA Astrophysics Data System (ADS)

    Efremov, Yu. N.; Efremov, E. Yu.

    Common star complexes are huge (0.3-1 kpc in diameter) groups of relatively young stars, associations and clusters. The complexes usually form regular chains along spiral arms of grand design galaxies, being evidently formed and supported by magneto- gravitational instability developing along an arm. Special attention is given to a few large complexes which have signatures of gravitational boundness, such as round shape and high central density. Concentrations of stars and clusters in such a complex in M51 galaxy were found in this paper; we concluded it is possible to suggest that the complex is gravitationally bound. It is also stressed that some properties of the giant complex in NGC 6946 (such as its semicircular and sharp Western edge) are still enigmatic.

  13. Complexation of Optoelectronic Systems

    NASA Astrophysics Data System (ADS)

    Boreisho, A. S.; Il‧in, M. Yu.; Konyaev, M. A.; Mikhailenko, A. S.; Morozov, A. V.; Strakhov, S. Yu.

    2016-06-01

    Problems of increasing the efficiency and the functionality of complex optoelectronic systems for monitoring real atmospheric conditions and of their use are discussed. It is shown by the example of a meteorological complex comprising an infrared wind-sensing lidar and an X-range Doppler radar that the complexation of probing systems working in different electromagnetic-radiation ranges opens up new opportunities for determining the meteorological parameters of a turbulent atmosphere and investigating the interaction of radiation with it.

  14. Complexity and schizophrenia.

    PubMed

    Fernández, Alberto; Gómez, Carlos; Hornero, Roberto; López-Ibor, Juan José

    2013-08-01

    Complexity estimators have been broadly utilized in schizophrenia investigation. Early studies reported increased complexity in schizophrenia patients, associated with a higher variability or "irregularity" of their brain signals. However, further investigations showed reduced complexities, thus introducing a clear divergence. Nowadays, both increased and reduced complexity values are reported. The explanation of such divergence is a critical issue to understand the role of complexity measures in schizophrenia research. Considering previous arguments a complementary hypothesis is advanced: if the increased irregularity of schizophrenia patients' neurophysiological activity is assumed, a "natural" tendency to increased complexity in EEG and MEG scans should be expected, probably reflecting an abnormal neuronal firing pattern in some critical regions such as the frontal lobes. This "natural" tendency to increased complexity might be modulated by the interaction of three main factors: medication effects, symptomatology, and age effects. Therefore, young, medication-naïve, and highly symptomatic (positive symptoms) patients are expected to exhibit increased complexities. More importantly, the investigation of these interacting factors by means of complexity estimators might help to elucidate some of the neuropathological processes involved in schizophrenia. PMID:22507763

  15. Kinetics of complex plasma with liquid droplets

    SciTech Connect

    Misra, Shikha; Sodha, M. S.; Mishra, S. K.

    2013-12-15

    This paper provides a theoretical basis for the reduction of electron density by spray of water (or other liquids) in hot plasma. This phenomenon has been observed in a hypersonic flight experiment for relief of radio black out, caused by high ionization in the plasma sheath of a hypersonic vehicle, re-entering the atmosphere. The analysis incorporates a rather little known phenomenon for de-charging of the droplets, viz., evaporation of ions from the surface and includes the charge balance on the droplets and number cum energy balance of electrons, ions, and neutral molecules; the energy balance of the evaporating droplets has also been taken into account. The analysis has been applied to a realistic situation and the transient variations of the charge and radius of water droplets, and other plasma parameters have been obtained and discussed. The analysis through made in the context of water droplets is applicable to all liquids.

  16. Kinetics of complex plasma with liquid droplets

    NASA Astrophysics Data System (ADS)

    Misra, Shikha; Mishra, S. K.; Sodha, M. S.

    2013-12-01

    This paper provides a theoretical basis for the reduction of electron density by spray of water (or other liquids) in hot plasma. This phenomenon has been observed in a hypersonic flight experiment for relief of radio black out, caused by high ionization in the plasma sheath of a hypersonic vehicle, re-entering the atmosphere. The analysis incorporates a rather little known phenomenon for de-charging of the droplets, viz., evaporation of ions from the surface and includes the charge balance on the droplets and number cum energy balance of electrons, ions, and neutral molecules; the energy balance of the evaporating droplets has also been taken into account. The analysis has been applied to a realistic situation and the transient variations of the charge and radius of water droplets, and other plasma parameters have been obtained and discussed. The analysis through made in the context of water droplets is applicable to all liquids.

  17. The Tom Core Complex

    PubMed Central

    Ahting, Uwe; Thun, Clemens; Hegerl, Reiner; Typke, Dieter; Nargang, Frank E.; Neupert, Walter; Nussberger, Stephan

    1999-01-01

    Translocation of nuclear-encoded preproteins across the outer membrane of mitochondria is mediated by the multicomponent transmembrane TOM complex. We have isolated the TOM core complex of Neurospora crassa by removing the receptors Tom70 and Tom20 from the isolated TOM holo complex by treatment with the detergent dodecyl maltoside. It consists of Tom40, Tom22, and the small Tom components, Tom6 and Tom7. This core complex was also purified directly from mitochondria after solubilization with dodecyl maltoside. The TOM core complex has the characteristics of the general insertion pore; it contains high-conductance channels and binds preprotein in a targeting sequence-dependent manner. It forms a double ring structure that, in contrast to the holo complex, lacks the third density seen in the latter particles. Three-dimensional reconstruction by electron tomography exhibits two open pores traversing the complex with a diameter of ∼2.1 nm and a height of ∼7 nm. Tom40 is the key structural element of the TOM core complex. PMID:10579717

  18. Performance Improvement Assuming Complexity

    ERIC Educational Resources Information Center

    Rowland, Gordon

    2007-01-01

    Individual performers, work teams, and organizations may be considered complex adaptive systems, while most current human performance technologies appear to assume simple determinism. This article explores the apparent mismatch and speculates on future efforts to enhance performance if complexity rather than simplicity is assumed. Included are…

  19. U1A Complex

    SciTech Connect

    2014-10-28

    Some of the most sophisticated experiments in the stockpile stewardship program are conducted in an environmentally safe manner, nearly 1000 feet below the ground at the site. The U1a complex a sprawling underground laboratory and tunnel complex is home to a number of unique capabilities.

  20. Complexity and Relations

    ERIC Educational Resources Information Center

    Lancaster, Jeanette Elizabeth

    2013-01-01

    A central feature of complexity is that it is based on non-linear, recursive relations. However, in most current accounts of complexity such relations, while non-linear, are based on the reductive relations of a Newtonian onto-epistemological framework. This means that the systems that are emergent from the workings of such relations are a…

  1. Visual Complexity: A Review

    ERIC Educational Resources Information Center

    Donderi, Don C.

    2006-01-01

    The idea of visual complexity, the history of its measurement, and its implications for behavior are reviewed, starting with structuralism and Gestalt psychology at the beginning of the 20th century and ending with visual complexity theory, perceptual learning theory, and neural circuit theory at the beginning of the 21st. Evidence is drawn from…

  2. Freestanding Complex Optical Scanners.

    ERIC Educational Resources Information Center

    Frisbie, David A.

    A complex freestanding optical mark recognition (OMR) scanner is one which is not on-line to an external processor; it has intelligence stemming from an internal processor located within the unit or system. The advantages and disadvantages of a complex OMR can best be assessed after identifying the scanning needs and constraints of the potential…

  3. COMPLEXITY IN ECOLOGICAL SYSTEMS

    EPA Science Inventory

    The enormous complexity of ecosystems is generally obvious under even the most cursory examination. In the modern world, this complexity is further augmented by the linkage of ecosystems to economic and social systems through the human use of the environment for technological pu...

  4. Bacterial formate hydrogenlyase complex

    PubMed Central

    McDowall, Jennifer S.; Murphy, Bonnie J.; Haumann, Michael; Palmer, Tracy; Armstrong, Fraser A.; Sargent, Frank

    2014-01-01

    Under anaerobic conditions, Escherichia coli can carry out a mixed-acid fermentation that ultimately produces molecular hydrogen. The enzyme directly responsible for hydrogen production is the membrane-bound formate hydrogenlyase (FHL) complex, which links formate oxidation to proton reduction and has evolutionary links to Complex I, the NADH:quinone oxidoreductase. Although the genetics, maturation, and some biochemistry of FHL are understood, the protein complex has never been isolated in an intact form to allow biochemical analysis. In this work, genetic tools are reported that allow the facile isolation of FHL in a single chromatographic step. The core complex is shown to comprise HycE (a [NiFe] hydrogenase component termed Hyd-3), FdhF (the molybdenum-dependent formate dehydrogenase-H), and three iron-sulfur proteins: HycB, HycF, and HycG. A proportion of this core complex remains associated with HycC and HycD, which are polytopic integral membrane proteins believed to anchor the core complex to the cytoplasmic side of the membrane. As isolated, the FHL complex retains formate hydrogenlyase activity in vitro. Protein film electrochemistry experiments on Hyd-3 demonstrate that it has a unique ability among [NiFe] hydrogenases to catalyze production of H2 even at high partial pressures of H2. Understanding and harnessing the activity of the FHL complex is critical to advancing future biohydrogen research efforts. PMID:25157147

  5. U1A Complex

    ScienceCinema

    None

    2015-01-09

    Some of the most sophisticated experiments in the stockpile stewardship program are conducted in an environmentally safe manner, nearly 1000 feet below the ground at the site. The U1a complex a sprawling underground laboratory and tunnel complex is home to a number of unique capabilities.

  6. Gold trifluoromethyl complexes.

    PubMed

    Gil-Rubio, Juan; Vicente, José

    2015-12-01

    This article reviews the synthesis, reactivity and applications of gold trifluoromethyl complexes, which are the only isolated perfluoroalkyl complexes of gold. The most reported examples are neutral Au(i) complexes of the type [Au(CF3)L], whereas only two Au(ii) trifluoromethyl complexes have been reported, both being diamagnetic and containing a strong Au-Au bond. A number of Au(iii) trifluoromethyl complexes have been prepared by oxidative addition of halogens or iodotrifluoromethane to Au(i) complexes or, in a few cases, by transmetallation reactions. Owing to the limitations of the available synthetic methods, a lower number of examples is known, particularly for the oxidation states (ii) and (iii). Gold trifluoromethyl complexes present singular characteristics, such as thermal stability, strong Au-C bonds and, in some cases, reactive α-C-F bonds. Some of the Au(iii) complexes reported, show unusually easy reductive elimination reactions of trifluoromethylated products which could be applied in the development of gold-catalyzed processes for the trifluoromethylation of organic compounds. PMID:26169553

  7. Complexity in Picture Books

    ERIC Educational Resources Information Center

    Sierschynski, Jarek; Louie, Belinda; Pughe, Bronwyn

    2015-01-01

    One of the key requirements of Common Core State Standards (CCSS) in English Language Arts is that students are able to read and access complex texts across all grade levels. The CCSS authors emphasize both the limitations and lack of accuracy in the current CCSS model of text complexity, calling for the development of new frameworks. In response…

  8. [Complexity: an introduction].

    PubMed

    Gómez, Carlos Alberto Palacio; Jaramillo, Francisco Luis Ochoa

    2011-01-01

    Complexity appears in the twentieth century as a way to understand many phenomena that are perceived as chaotic and complex from classical thought, which still persist in our way of explaining the world. Its purpose is to study the complex and adaptive systems that are sensitive to initial conditions. Some of the characteristics of complex thought are systemic perspective, autopoiesis, self-organization, emergent properties, unpredictability of the systems, analogic thought, and the complementarity of the phenomena, among others. Living systems respond to a complex logic, and in that sense, our vision of human populations and patients, and how we try to solve problems and human diseases, should be open to the possibilities that arise from this form of understand the world. PMID:21503430

  9. Leading healthcare in complexity.

    PubMed

    Cohn, Jeffrey

    2014-12-01

    Healthcare institutions and providers are in complexity. Networks of interconnections from relationships and technology create conditions in which interdependencies and non-linear dynamics lead to surprising, unpredictable outcomes. Previous effective approaches to leadership, focusing on top-down bureaucratic methods, are no longer effective. Leading in complexity requires leaders to accept the complexity, create an adaptive space in which innovation and creativity can flourish and then integrate the successful practices that emerge into the formal organizational structure. Several methods for doing adaptive space work will be discussed. Readers will be able to contrast traditional leadership approaches with leading in complexity. They will learn new behaviours that are required of complexity leaders, along with challenges they will face, often from other leaders within the organization. PMID:25815410

  10. Nickel Hydride Complexes.

    PubMed

    Eberhardt, Nathan A; Guan, Hairong

    2016-08-10

    Nickel hydride complexes, defined herein as any molecules bearing a nickel hydrogen bond, are crucial intermediates in numerous nickel-catalyzed reactions. Some of them are also synthetic models of nickel-containing enzymes such as [NiFe]-hydrogenase. The overall objective of this review is to provide a comprehensive overview of this specific type of hydride complexes, which has been studied extensively in recent years. This review begins with the significance and a very brief history of nickel hydride complexes, followed by various methods and spectroscopic or crystallographic tools used to synthesize and characterize these complexes. Also discussed are stoichiometric reactions involving nickel hydride complexes and how some of these reactions are developed into catalytic processes. PMID:27437790

  11. Profil'-1 measuring complex

    SciTech Connect

    Andrianov, V.R.; Petrov, A.P.

    1985-04-01

    This paper describes the Profil'-1 hydroacoustic measuring complex. The complex provides documentary information on the bottom profile of reservoirs, the configuration and geometric dimensions of underwater trenches, the spatial position of pipes in uncovered or washedout trenches, the thickness of a layer covering underwater pipes, etc. The complex can also be used to solve other industrial problems such as hydraulic exploration and searching for sunken objects. The Profil'-1 complex is designed for use on board small craft under field conditions with periodic transportation from storage bases to the operating location and back. The complex uses an echo-pulse method for determining the distance and coordinates of objects with the aid of an ultrasonic transceiver in an aqueous medium. Structurally, the complex consists of four main units: a BA-1 vertical sounding antenna unit; a BAS-1 antenna scanning unit; a BFOS-1 signal shaping and processing unit, and a BR-1 recording unit. Use of the complex in pipeline construction and the oil and gas industry will provide a considerable economic gain by reducing the number of diver inspections of underwater pipelines.

  12. Selenophene transition metal complexes

    SciTech Connect

    White, C.J.

    1994-07-27

    This research shows that selenophene transition metal complexes have a chemistry that is similar to their thiophene analogs. Selenophene coordination has been demonstrated and confirmed by molecular structure in both the {eta}{sup 5}- and the {eta}{sup 1}(Se)-coordination modes. The reaction chemistry of selenophene complexes closely resembles that of the analogous thiophene complexes. One major difference, however, is that selenophene is a better donor ligand than thiophene making the selenophene complexes more stable than the corresponding thiophene complexes. The {sup 77}Se NMR chemical shift values for selenophene complexes fall within distinct regions primarily depending on the coordination mode of the selenophene ligand. In the final paper, the C-H bond activation of {eta}{sup 1}(S)-bound thiophenes, {eta}{sup 1}(S)-benzothiophene and {eta}{sup 1}(Se)-bound selenophenes has been demonstrated. The deprotonation and rearrangement of the {eta}{sup 1}(E)-bound ligand to the carbon bound L-yl complex readily occurs in the presence of base. Reprotonation with a strong acid gives a carbene complex that is unreactive towards nucleophilic attack at the carbene carbon and is stable towards exposure to air. The molecular structure of [Cp(NO)(PPh{sub 3})Re(2-benzothioenylcarbene)]O{sub 3}SCF{sub 3} was determined and contains a Re-C bond with substantial double bond character. Methyl substitution for the thienylcarbene or selenylcarbene gives a carbene that rearranges thermally to give back the {eta}{sup 1}(E)-bound complex. Based on these model reactions, a new mechanism for the H/D exchange of thiophene over the hydrodesulfurization catalyst has been proposed.

  13. Complexity and robustness

    PubMed Central

    Carlson, J. M.; Doyle, John

    2002-01-01

    Highly optimized tolerance (HOT) was recently introduced as a conceptual framework to study fundamental aspects of complexity. HOT is motivated primarily by systems from biology and engineering and emphasizes, (i) highly structured, nongeneric, self-dissimilar internal configurations, and (ii) robust yet fragile external behavior. HOT claims these are the most important features of complexity and not accidents of evolution or artifices of engineering design but are inevitably intertwined and mutually reinforcing. In the spirit of this collection, our paper contrasts HOT with alternative perspectives on complexity, drawing on real-world examples and also model systems, particularly those from self-organized criticality. PMID:11875207

  14. Controllability of Complex Systems

    NASA Astrophysics Data System (ADS)

    Slotine, Jean-Jacques

    2013-03-01

    We review recent work on controllability of complex systems. We also discuss the interplay of our results with questions of synchronization, and point out key directions of future research. Work done in collaboration with Yang-Yu Liu, Center for Complex Network Research and Departments of Physics, Computer Science and Biology, Northeastern University and Center for Cancer Systems Biology, Dana-Farber Cancer Institute; and Albert-László Barabási, Center for Complex Network Research and Departments of Physics, Computer Science and Biology, Northeastern University; Center for Cancer Systems Biology, Dana-Farber Cancer Institute; and Department of Medicine, Brigham and Women's Hospital, Harvard Medical School.

  15. Complexity and forensic pathology.

    PubMed

    Jones, Richard Martin

    2015-12-01

    It has become increasingly apparent that nonlinearity and complexity are the norm in human physiological systems, the relevance of which is informing an enhanced understanding of basic pathological processes such as inflammation, the host response to severe trauma, and critical illness. This article will explore how an understanding of nonlinear systems and complexity might inform the study of the pathophysiology of deaths of medicolegal interest, and how 'complexity thinking' might usefully be incorporated into modern forensic medicine and forensic pathology research, education and practice. PMID:26372537

  16. Complex intuitionistic fuzzy sets

    NASA Astrophysics Data System (ADS)

    Alkouri, Abdulazeez (Moh'd. Jumah) S.; Salleh, Abdul Razak

    2012-09-01

    This paper presents a new concept of complex intuitionistic fuzzy set (CIFS) which is generalized from the innovative concept of a complex fuzzy set (CFS) by adding the non-membership term to the definition of CFS. The novelty of CIFS lies in its ability for membership and non-membership functions to achieve more range of values. The ranges of values are extended to the unit circle in complex plane for both membership and non-membership functions instead of [0, 1] as in the conventional intuitionistic fuzzy functions. We define basic operations namely complement, union, and intersection on CIFSs. Properties of these operations are derived.

  17. Afterglow Complex Plasma

    SciTech Connect

    Samarian, A. A.; Boufendi, L.; Mikikian, M.

    2008-09-07

    The review of the first detailed experimental and theoretical studies of complex plasma in RF discharge afterglow is presented. The studies have been done in a frame of FAST collaborative research project between Complex Plasma Laboratory of the University of Sydney and the GREMI laboratory of Universite d'Orleans. We examined the existing models of plasma decay, presents experimental observations of dust dynamics under different afterglow complex plasma conditions, presents the experimental data obtained (in particular the presence of positively charged particles in discharge afterglow), discusses the use of dust particles as a probe to study the diffusion losses in afterglow plasmas.

  18. Complex equiangular tight frames

    NASA Astrophysics Data System (ADS)

    Tropp, Joel A.

    2005-08-01

    A complex equiangular tight frame (ETF) is a tight frame consisting of N unit vectors in Cd whose absolute inner products are identical. One may view complex ETFs as a natural geometric generalization of an orthonormal basis. Numerical evidence suggests that these objects do not arise for most pairs (d, N). The goal of this paper is to develop conditions on (d, N) under which complex ETFs can exist. In particular, this work concentrates on the class of harmonic ETFs, in which the components of the frame vectors are roots of unity. In this case, it is possible to leverage field theory to obtain stringent restrictions on the possible values for (d, N).

  19. Complex coacervate core micelles.

    PubMed

    Voets, Ilja K; de Keizer, Arie; Cohen Stuart, Martien A

    2009-01-01

    In this review we present an overview of the literature on the co-assembly of neutral-ionic block, graft, and random copolymers with oppositely charged species in aqueous solution. Oppositely charged species include synthetic (co)polymers of various architectures, biopolymers - such as proteins, enzymes and DNA - multivalent ions, metallic nanoparticles, low molecular weight surfactants, polyelectrolyte block copolymer micelles, metallo-supramolecular polymers, equilibrium polymers, etcetera. The resultant structures are termed complex coacervate core/polyion complex/block ionomer complex/interpolyelectrolyte complex micelles (or vesicles); i.e., in short C3Ms (or C3Vs) and PIC, BIC or IPEC micelles (and vesicles). Formation, structure, dynamics, properties, and function will be discussed. We focus on experimental work; theory and modelling will not be discussed. Recent developments in applications and micelles with heterogeneous coronas are emphasized. PMID:19038373

  20. Complexity at mesoscopic lengthscale.

    PubMed

    Egami, T

    2015-09-01

    Modern materials are often complex in the structure at mesoscale. The method of pair-density function (PDF) is a powerful tool to characterize mesoscopic structure, bridging short- and long-range structures. PMID:26306189

  1. Reconstruction Using Witness Complexes

    PubMed Central

    Oudot, Steve Y.

    2010-01-01

    We present a novel reconstruction algorithm that, given an input point set sampled from an object S, builds a one-parameter family of complexes that approximate S at different scales. At a high level, our method is very similar in spirit to Chew’s surface meshing algorithm, with one notable difference though: the restricted Delaunay triangulation is replaced by the witness complex, which makes our algorithm applicable in any metric space. To prove its correctness on curves and surfaces, we highlight the relationship between the witness complex and the restricted Delaunay triangulation in 2d and in 3d. Specifically, we prove that both complexes are equal in 2d and closely related in 3d, under some mild sampling assumptions. PMID:21643440

  2. Reconstruction Using Witness Complexes.

    PubMed

    Guibas, Leonidas J; Oudot, Steve Y

    2008-10-01

    We present a novel reconstruction algorithm that, given an input point set sampled from an object S, builds a one-parameter family of complexes that approximate S at different scales. At a high level, our method is very similar in spirit to Chew's surface meshing algorithm, with one notable difference though: the restricted Delaunay triangulation is replaced by the witness complex, which makes our algorithm applicable in any metric space. To prove its correctness on curves and surfaces, we highlight the relationship between the witness complex and the restricted Delaunay triangulation in 2d and in 3d. Specifically, we prove that both complexes are equal in 2d and closely related in 3d, under some mild sampling assumptions. PMID:21643440

  3. A complex legacy

    NASA Astrophysics Data System (ADS)

    Moore, Cristopher

    2011-11-01

    In his tragically short life, Alan Turing helped define what computing machines are capable of, and where they reach inherent limits. His legacy is still felt every day, in areas ranging from computational complexity theory to cryptography and quantum computing.

  4. Specialist complex care.

    PubMed

    Oliver, Susan

    2016-08-01

    I agree with your editorial on how NHS England and the Department of Health (DH) have failed to realise that specialist care for complex diseases requires experienced and knowledgeable support. PMID:27484551

  5. Complex Regional Pain Syndrome

    MedlinePlus

    Complex regional pain syndrome (CRPS) is a chronic pain condition. It causes intense pain, usually in the arms, hands, legs, or feet. ... in skin temperature, color, or texture Intense burning pain Extreme skin sensitivity Swelling and stiffness in affected ...

  6. Cytarabine Lipid Complex Injection

    MedlinePlus

    Cytarabine lipid complex is used to treat lymphomatous meningitis (a type of cancer in the covering of ... to take.tell your doctor if you have meningitis. Your doctor will probably not want you to ...

  7. Complex Flow Workshop Report

    SciTech Connect

    none,

    2012-05-01

    This report documents findings from a workshop on the impacts of complex wind flows in and out of wind turbine environments, the research needs, and the challenges of meteorological and engineering modeling at regional, wind plant, and wind turbine scales.

  8. Pigment-protein complexes

    SciTech Connect

    Siegelman, H W

    1980-01-01

    The photosynthetically-active pigment protein complexes of procaryotes and eucaryotes include chlorophyll proteins, carotenochlorophyll proteins, and biliproteins. They are either integral components or attached to photosynthetic membranes. Detergents are frequently required to solubilize the pigment-protein complexes. The membrane localization and detergent solubilization strongly suggest that the pigment-protein complexes are bound to the membranes by hydrophobic interactions. Hydrophobic interactions of proteins are characterized by an increase in entropy. Their bonding energy is directly related to temperature and ionic strength. Hydrophobic-interaction chromatography, a relatively new separation procedure, can furnish an important method for the purification of pigment-protein complexes. Phycobilisome purification and properties provide an example of the need to maintain hydrophobic interactions to preserve structure and function.

  9. Complex/Symplectic Mirrors

    SciTech Connect

    Chuang, Wu-yen; Kachru, Shamit; Tomasiello, Alessandro; /Stanford U., ITP

    2005-10-28

    We construct a class of symplectic non-Kaehler and complex non-Kaehler string theory vacua, extending and providing evidence for an earlier suggestion by Polchinski and Strominger. The class admits a mirror pairing by construction. Comparing hints from a variety of sources, including ten-dimensional supergravity and KK reduction on SU(3)-structure manifolds, suggests a picture in which string theory extends Reid's fantasy to connect classes of both complex non-Kaehler and symplectic non-Kaehler manifolds.

  10. Inside the complexity labyrinth

    NASA Astrophysics Data System (ADS)

    Fraser, Gordon

    2010-02-01

    Although the world we live in is complex, complexity as a science does not have a long history. For generations, most physicists tried to understand everything in terms of interactions between pairs of idealized "test particles". Then, about a 100 years ago, Henri Poincaré pointed out that a fully interacting three-body system was not just the sum of its three component pairs. The famous "three-body problem" was born.

  11. Interglacial complex and solcomplex

    NASA Astrophysics Data System (ADS)

    Schirmer, Wolfgang

    2010-03-01

    All younger Pleistocene interglacials form interglacial complexes. The term interglacial complex is a short term for a tight complex of interglacials, interstadials and breviglacials, separating a complex of warm periods from the long glacial periods (euglacials). In the terrestric environment the interglacial complexes are represented by soil clusters (solcomplexes). Therein which occur interglacial and interstadial soils of different types in the loess environment separated by thin beds of loess or loess derivates (breviglacials). This article considers the mutilation and simulation of solcomplexes. Frequently, fossil solcomplexes present themselves as diminished to a few soils or to one single soil. This mutilation of solcomplexes can be due to soil convergence (soils of different warm periods — interglacials, interstadials — merge to form optically one soil), syn-solcomplex erosion or post-solcomplex erosion and sometimes to soil disguise. Conversely solcomplexes may be simulated by narrowing of soils which belong to different interglacial complexes and moreover by soil divergence (splitting of a soil of one single warm period by an interlayer of rock) or by reworked soil sediment.

  12. Synchronization in complex dynamical networks coupled with complex chaotic system

    NASA Astrophysics Data System (ADS)

    Wei, Qiang; Xie, Cheng-Jun; Wang, Bo

    2015-11-01

    This paper investigates synchronization in complex dynamical networks with time delay and perturbation. The node of complex dynamical networks is composed of complex chaotic system. A complex feedback controller is designed to realize different component of complex state variable synchronize up to different scaling complex function when complex dynamical networks realize synchronization. The synchronization scaling function is changed from real field to complex field. Synchronization in complex dynamical networks with constant delay and time-varying coupling delay are investigated, respectively. Numerical simulations show the effectiveness of the proposed method.

  13. Is "In Consortio Cum Parentibus" the New "In Loco Parentis?"

    ERIC Educational Resources Information Center

    Henning, Gavin

    2007-01-01

    "In loco parentis" had been the philosophical foundation of higher education policy and practice since 1913 when it was established as a legal doctrine in Gott v. Berea. The doctrine defined the relationship between colleges, students, and parents. That relationship has changed with the death of "in loco parentis" in Dixon v. Alabama Board of…

  14. "Cum Poterit"--Rhetorical Exercises for Transitional and Developmental Students

    ERIC Educational Resources Information Center

    Church, A. P.; Sigrell, Anders

    2005-01-01

    Recently, scholars of rhetoric and composition have shown much interest in the ancient composition exercises known as "progymnasmata". This paper explains how these exercises, which provided ancient students with a transitional curriculum between grammar and rhetoric, have theoretical and practical merit for contemporary compositional pedagogy. It…

  15. Colloquamur Latine cum Pueris Puellesque: Latin in the Middle School.

    ERIC Educational Resources Information Center

    Graber, Charles F.; Norton, Harriet S.

    Guidelines for the development of a Latin curriculum for the middle school, with specific suggestions as to content and methodology, are presented in this manual. The material, oriented toward new approaches in the teaching of the Latin and Graeco-Roman cultures, strives to develop proficiency in the skills of listening, speaking, reading, and…

  16. Cummings Memorial Lecture - 1975. The market basket: food for thought.

    PubMed

    Deichman, W B

    1975-06-01

    The world food crisis is as critical today as when it was debated at the 1974 World Food Conference in Rome. Since the United States and Canada-and to a lesser extent, Australia and New Zealand-lead in the production of corn, wheat and soybeans, the North American "bread basket" has become the "market basket" of the world. For welfare, economic, and political reasons, our energies, resources, and deliberations must be expanded toward optimum production of wholesome food products. I do not recommend that we permit food additives in "questionably" safe or excessive concentrations in our agricultural products. I do recommend, however, that tolerance limits for food additives be established based on a comprehensive review of all contributing factors-the world food crisis and the rational interpretation of both positive and negative animal data as they relate to man. As Dr. Herbert Stokinger put it so aptly: "Avoid the establishment of unnecessarily severe standards." 2. Funds for research and teaching of food and nutrition should be greatly increased, so that all who can read and write may be made aware of the daily dietary requirements for the maintenance of good health. 3. Unsubstantiated scare tactics in publications of the scientific and lay press can only lead to well-intended but often emotionally-inspired restrictions, ordinances, and laws. Such decisions are likely to either under- or over-define the requirements and standards for food additives and other chemicals which are important to the well-being of the populace. PMID:779439

  17. Environmental Development cum Forest Plantation Planning and Management.

    ERIC Educational Resources Information Center

    Katoch, C. D.

    This textbook covers environmental conservation through forest plantation planning and management for all levels of forestry professionals and non-professionals in India and abroad. The book is divided into six parts and 29 sections in sequential order. Part I contains details on site selection, site preparations, site clearance, layout, and…

  18. Cell complexes through time

    NASA Astrophysics Data System (ADS)

    Klette, Reinhard

    2000-10-01

    The history of cell complexes is closely related to the birth and development of topology in general. Johann Benedict Listing (1802 - 1882) introduced the term 'topology' into mathematics in a paper published in 1847, and he also defined cell complexes for the first time in a paper published in 1862. Carl Friedrich Gauss (1777 - 1855) is often cited as the one who initiated these ideas, but he did not publish either on topology or on cell complexes. The pioneering work of Leonhard Euler (1707 - 1783) on graphs is also often cited as the birth of topology, and Euler's work was cited by Listing in 1862 as a stimulus for his research on cell complexes. There are different branches in topology which have little in common: point set topology, algebraic topology, differential topology etc. Confusion may arise if just 'topology' is specified, without clarifying the used concept. Topological subjects in mathematics are often related to continuous models, and therefore quite irrelevant to computer based solutions in image analysis. Compared to this, only a minority of topology publications in mathematics addresses discrete spaces which are appropriate for computer-based image analysis. In these cases, often the notion of a cell complex plays a crucial role. This paper briefly reports on a few of these publications. This paper is not intended to cover the very lively progress in cell complex studies within the context of image analysis during the last two decades. Basically it stops its historic review at the time when this subject in image analysis research gained speed in 1980 - 1990. As a general point of view, the paper indicates that image analysis contributes to a fusion of topological concepts, the geometric and the abstract cell structure approach and point set topology, which may lead towards new problems for the study of topologies defined on geometric or abstract cell complexes.

  19. Controllability of Complex Networks

    NASA Astrophysics Data System (ADS)

    Liu, Yang; Slotine, Jean-Jacques; Barabasi, Albert-Laszlo

    2011-03-01

    The ultimate proof of our understanding of natural or technological systems is reflected in our ability to control them. While control theory offers mathematical tools to steer engineered systems towards a desired state, we lack a general framework to control complex self-organized systems, like the regulatory network of a cell or the Internet. Here we develop analytical tools to study the controllability of an arbitrary complex directed network, identifying the set of driver nodes whose time-dependent control can guide the system's dynamics. We apply these tools to real and model networks, finding that sparse inhomogeneous networks, which emerge in many real complex systems, are the most difficult to control. In contrast, dense and homogeneous networks can be controlled via a few driver nodes. Counterintuitively, we find that in both model and real systems the driver nodes tend to avoid the hubs. We show that the robustness of control to link failure is determined by a core percolation problem, helping us understand why many complex systems are relatively insensitive to link deletion. The developed approach offers a framework to address the controllability of an arbitrary network, representing a key step towards the eventual control of complex systems.

  20. Quantum Complexity in Graphene

    NASA Astrophysics Data System (ADS)

    Baskaran, G.

    Carbon has a unique position among elements in the periodic table. It produces an allotrope, graphene, a mechanically robust two dimensional semimetal. The multifarious properties that graphene exhibits has few parallels among elemental metals. From simplicity, namely carbon atoms connected by pure sp2 bonds, a wealth of novel quantum properties emerge. In classical complex systems such as a spin glass or a finance market, several competing agents or elements are responsible for unanticipated and difficult to predict emergent properties. The complex (sic) structure of quantum mechanics is responsbile for an unanticipated set of emergent properties in graphene. We call this quantum complexity. In fact, most quantum systems, phenomena and modern quantum field theory could be viewed as examples of quantum complexity. After giving a brief introduction to the quantum complexity we focus on our own work, which indicates the breadth in the type of quantum phenomena that graphene could support. We review our theoretical suggestions of, (i) spin-1 collective mode in netural graphene, (ii) relativistic type of phenomena in crossed electric and magnetic fields, (iii) room temperature superconductivity in doped graphene and (iv) composite Fermi sea in neutral graphene in uniform magnetic field and (v) two-channel Kondo effect. Except for the relativistic type of phenomena, the rest depend in a fundamental way on a weak electron correlation that exists in the broad two-dimensional band of graphene.

  1. Complexes and imagination.

    PubMed

    Kast, Verena

    2014-11-01

    Fantasies as imaginative activities are seen by Jung as expressions of psychic energy. In the various descriptions of active imagination the observation of the inner image and the dialogue with inner figures, if possible, are important. The model of symbol formation, as Jung describes it, can be experienced in doing active imagination. There is a correspondence between Jung's understanding of complexes and our imaginations: complexes develop a fantasy life. Complex episodes are narratives of difficult dysfunctional relationship episodes that have occurred repeatedly and are internalized with episodic memory. This means that the whole complex episode (the image for the child and the image for the aggressor, connected with emotions) is internalized and can get constellated in everyday relationship. Therefore inner dialogues do not necessarily qualify as active imaginations, often they are the expression of complex-episodes, very similar to fruitless soliloquies. If imaginations of this kind are repeated, new symbols and new possibilities of behaviour are not found. On the contrary, old patterns of behaviour and fantasies are perpetuated and become cemented. Imaginations of this kind need an intervention by the analyst. In clinical examples different kinds of imaginations are discussed. PMID:25331506

  2. Hydridomethyl iridium complex

    DOEpatents

    Bergman, Robert G.; Buchanan, J. Michael; Stryker, Jeffrey M.; Wax, Michael J.

    1989-01-01

    A process for functionalizing methane comprising: (a) reacting methane with a hydridoalkyl metal complex of the formula: CpIr[P(R.sub.1).sub.3 ]H(R.sub.2) wherein Cp represents a cyclopentadienyl or alkylcyclopentadienyl radical having from 1 to 5 carbon atoms; Ir represents an iridium atom; P represents a phosphorus atom; R.sub.1 represents an alkyl group; R.sub.2 represents an alkyl group having at least two carbon atoms; and H represents a hydrogen atom, in the presence of a liquid alkane R.sub.3 H having at least three carbon atoms to form a hydridomethyl complex of the formula: CpIr[P(R.sub.1).sub.3 ]HMe where Me represents a methyl radical. (b) reacting said hydridomethyl complex with an organic halogenating agent such as a tetrahalomethane or a haloform of the formulas: CX'X"X'"X"" or CHX'X"X'"; wherein X', X", X"', and X"" represent halogens selected from bromine, iodine and chlorine, to halomethyl complex of step (a) having the formula: CpIr[P(R.sub.1).sub.3 ]MeX: (c) reacting said halomethyl complex with a mercuric halide of the formula HgX.sub.2 to form a methyl mercuric halide of the formula HgMeX; and (d) reacting said methyl mercuric halide with a molecular halogen of the formula X.sub.2 to form methyl halide.

  3. Synchronization in complex networks

    SciTech Connect

    Arenas, A.; Diaz-Guilera, A.; Moreno, Y.; Zhou, C.; Kurths, J.

    2007-12-12

    Synchronization processes in populations of locally interacting elements are in the focus of intense research in physical, biological, chemical, technological and social systems. The many efforts devoted to understand synchronization phenomena in natural systems take now advantage of the recent theory of complex networks. In this review, we report the advances in the comprehension of synchronization phenomena when oscillating elements are constrained to interact in a complex network topology. We also overview the new emergent features coming out from the interplay between the structure and the function of the underlying pattern of connections. Extensive numerical work as well as analytical approaches to the problem are presented. Finally, we review several applications of synchronization in complex networks to different disciplines: biological systems and neuroscience, engineering and computer science, and economy and social sciences.

  4. Nonergodic complexity management

    NASA Astrophysics Data System (ADS)

    Piccinini, Nicola; Lambert, David; West, Bruce J.; Bologna, Mauro; Grigolini, Paolo

    2016-06-01

    Linear response theory, the backbone of nonequilibrium statistical physics, has recently been extended to explain how and why nonergodic renewal processes are insensitive to simple perturbations, such as in habituation. It was established that a permanent correlation results between an external stimulus and the response of a complex system generating nonergodic renewal processes, when the stimulus is a similar nonergodic process. This is the principle of complexity management, whose proof relies on ensemble distribution functions. Herein we extend the proof to the nonergodic case using time averages and a single time series, hence making it usable in real life situations where ensemble averages cannot be performed because of the very nature of the complex systems being studied.

  5. Synchronization in complex networks

    NASA Astrophysics Data System (ADS)

    Arenas, Alex; Díaz-Guilera, Albert; Kurths, Jurgen; Moreno, Yamir; Zhou, Changsong

    2008-12-01

    Synchronization processes in populations of locally interacting elements are the focus of intense research in physical, biological, chemical, technological and social systems. The many efforts devoted to understanding synchronization phenomena in natural systems now take advantage of the recent theory of complex networks. In this review, we report the advances in the comprehension of synchronization phenomena when oscillating elements are constrained to interact in a complex network topology. We also take an overview of the new emergent features coming out from the interplay between the structure and the function of the underlying patterns of connections. Extensive numerical work as well as analytical approaches to the problem are presented. Finally, we review several applications of synchronization in complex networks to different disciplines: biological systems and neuroscience, engineering and computer science, and economy and social sciences.

  6. Viral quasispecies complexity measures.

    PubMed

    Gregori, Josep; Perales, Celia; Rodriguez-Frias, Francisco; Esteban, Juan I; Quer, Josep; Domingo, Esteban

    2016-06-01

    Mutant spectrum dynamics (changes in the related mutants that compose viral populations) has a decisive impact on virus behavior. The several platforms of next generation sequencing (NGS) to study viral quasispecies offer a magnifying glass to study viral quasispecies complexity. Several parameters are available to quantify the complexity of mutant spectra, but they have limitations. Here we critically evaluate the information provided by several population diversity indices, and we propose the introduction of some new ones used in ecology. In particular we make a distinction between incidence, abundance and function measures of viral quasispecies composition. We suggest a multidimensional approach (complementary information contributed by adequately chosen indices), propose some guidelines, and illustrate the use of indices with a simple example. We apply the indices to three clinical samples of hepatitis C virus that display different population heterogeneity. Areas of virus biology in which population complexity plays a role are discussed. PMID:27060566

  7. Complexity and Fly Swarms

    NASA Astrophysics Data System (ADS)

    Cates, Grant; Murray, Joelle

    Complexity is the study of phenomena that emerge from a collection of interacting objects and arises in many systems throughout physics, biology, finance, economics and more. Certain kinds of complex systems can be described by self-organized criticality (SOC). An SOC system is one that is internally driven towards some critical state. Recent experimental work suggests scaling behavior of fly swarms-one of the hallmarks of an SOC system. Our goal is to look for SOC behavior in computational models of fly swarms.

  8. Luminescent macrocyclic lanthanide complexes

    DOEpatents

    Raymond, Kenneth N; Corneillie, Todd M; Xu, Jide

    2014-05-20

    The present invention provides a novel class of macrocyclic compounds as well as complexes formed between a metal (e.g., lanthanide) ion and the compounds of the invention. Preferred complexes exhibit high stability as well as high quantum yields of lanthanide ion luminescence in aqueous media without the need for secondary activating agents. Preferred compounds incorporate hydroxy-isophthalamide moieties within their macrocyclic structure and are characterized by surprisingly low, non-specific binding to a variety of polypeptides such as antibodies and proteins as well as high kinetic stability. These characteristics distinguish them from known, open-structured ligands.

  9. Luminescent macrocyclic lanthanide complexes

    DOEpatents

    Raymond, Kenneth N.; Corneillie, Todd M.; Xu, Jide

    2012-05-08

    The present invention provides a novel class of macrocyclic compounds as well as complexes formed between a metal (e.g., lanthanide) ion and the compounds of the invention. Preferred complexes exhibit high stability as well as high quantum yields of lanthanide ion luminescence in aqueous media without the need for secondary activating agents. Preferred compounds incorporate hydroxy-isophthalamide moieties within their macrocyclic structure and are characterized by surprisingly low, non-specific binding to a variety of polypeptides such as antibodies and proteins as well as high kinetic stability. These characteristics distinguish them from known, open-structured ligands.

  10. Planning Complex Projects Automatically

    NASA Technical Reports Server (NTRS)

    Henke, Andrea L.; Stottler, Richard H.; Maher, Timothy P.

    1995-01-01

    Automated Manifest Planner (AMP) computer program applies combination of artificial-intelligence techniques to assist both expert and novice planners, reducing planning time by orders of magnitude. Gives planners flexibility to modify plans and constraints easily, without need for programming expertise. Developed specifically for planning space shuttle missions 5 to 10 years ahead, with modifications, applicable in general to planning other complex projects requiring scheduling of activities depending on other activities and/or timely allocation of resources. Adaptable to variety of complex scheduling problems in manufacturing, transportation, business, architecture, and construction.